顔写真

ナカムラ テツヤ
中村 哲也
Tetsuya Nakamura
所属
国際放射光イノベーション・スマート研究センター 放射光次世代計測科学連携研究部門
職名
教授
学位
  • 博士(工学)(東京大学)

  • 修士(工学)(東京大学)

経歴 12

  • 2020年7月 ~ 継続中
    東北大学国際放射光イノベーション・スマート研究センター 放射光次世代計測科学連携研究部門 教授

  • 2020年1月 ~ 2020年6月
    東北大学多元物質科学研究所 放射光次世代計測科学連携研究部門 教授

  • 2019年4月 ~ 2019年12月
    公益財団法人高輝度光科学研究センター 分光・イメージング推進室 主席研究員

  • 2017年10月 ~ 2019年3月
    公益財団法人高輝度光科学研究センター 利用研究促進部門 主席研究員

  • 2015年2月 ~ 2017年9月
    公益財団法人高輝度光科学研究センター 利用研究促進部門 副主席研究員

  • 2006年4月 ~ 2015年1月
    公益財団法人高輝度光科学研究センター 利用研究促進部門 主幹研究員

  • 2005年10月 ~ 2006年3月
    公益財団法人高輝度光科学研究センター 利用研究促進部門 副主幹研究員

  • 2004年4月 ~ 2005年9月
    公益財団法人高輝度光科学研究センター 利用研究促進部門Ⅰ 副主幹研究員

  • 2002年10月 ~ 2004年3月
    公益財団法人高輝度光科学研究センター 利用研究促進部門Ⅰ 研究員

  • 2001年1月 ~ 2002年10月
    東京大学生産技術研究所 第4部・七尾研究質 助手

  • 1998年4月 ~ 2000年12月
    特定国立研究開発法人理化学研究所 磁性研究室 基礎科学特別研究員

  • 1996年4月 ~ 1998年3月
    東京大学生産技術研究所 第4部 七尾研究室 日本学術振興会 特別研究員(DC2)

︎全件表示 ︎最初の5件までを表示

委員歴 1

  • 日本学術振興会・産学協力研究委員会・第147委員会 委員(学界)

    2013年10月 ~ 2023年9月

研究分野 1

  • ナノテク・材料 / 金属材料物性 /

論文 258

  1. Element- and orbital-selective magnetic coherent rotation at the first-order phase transition of a hard uniaxial ferrimagnet 査読有り

    Sh. Yamamoto, D. I. Gorbunov, H. Akai, H. Yasumura, Y. Kotani, T. Nakamura, T. Kato, N. V. Mushnikov, A. V. Andreev, H. Nojiri, J. Wosnitza

    Physical Review B 2020年5月19日

    DOI: 10.1103/PhysRevB.101.174430  

  2. Quantitative identification of constituent phases in a Nd-Fe-B-Cu sintered magnet and temperature dependent change of electron density of Nd<inf>2</inf>Fe<inf>14</inf>B studied by synchrotron X-ray diffraction 査読有り

    Hiroyuki Okazaki, David Billington, Naruki Tsuji, Wakana Ueno, Yoshinori Kotani, Shogo Kawaguchi, Kunihisa Sugimoto, Kentaro Toyoki, Tomoki Fukagawa, Takeshi Nishiuchi, Kazuhiro Hono, Satoshi Hirosawa, Tetsuya Nakamura

    Acta Materialia 181 530-536 2019年12月

    DOI: 10.1016/j.actamat.2019.10.004  

    ISSN:1359-6454

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    © 2019 Acta Materialia Inc. We have measured the temperature dependent XRD profiles of an isotropic Nd-Fe-B-Cu sintered magnet during the annealing process. Through Rietveld refinement, we demonstrate the changes in the volume fractions of a Nd2Fe14B main-phase and the other secondary phases as a function of increasing temperature up to 1047 °C. The secondary phases mainly include dhcp-Nd, fcc-NdOx, and hcp-Nd2O3 at room temperature and fcc-Nd at elevated temperatures. The main phase starts melting above 900 °C but remains relatively stable up to 600 °C, while the dhcp-Nd phase completely disappears at around 600 °C. Taking an advantage of the excellent quality of the XRD profiles in the powdered single crystal sample, we have also investigated the electron density distribution of main-phase by MEM/Rietveld analysis in order to elucidate the origin of the large magnetic anisotropy. The change in asymmetric part of electron density is derived by the subtraction of the electron density distributions between those recorded at -123 and -173 °C, where the spin reorientation transition at -138 °C changes the magnetic anisotropy. This change is attributed to be a difference of electron density distribution between Nd f and g sites of the Nd2Fe14B, relating to the magnetic anisotropy.

  3. Unmasking the interior magnetic domain structure and evolution in Nd-Fe-B sintered magnets through high-field magnetic imaging of the fractured surface 査読有り

    David Billington, Kentaro Toyoki, Hiroyuki Okazaki, Yoshinori Kotani, Tomoki Fukagawa, Takeshi Nishiuchi, Satoshi Hirosawa, Tetsuya Nakamura

    Physical Review Materials 2 (10) 2018年10月

    出版者・発行元:American Physical Society ({APS})

    DOI: 10.1103/physrevmaterials.2.104413  

    ISSN:2475-9953

    eISSN:2475-9953

  4. Realization of a scanning soft X-ray microscope for magnetic imaging under high magnetic fields 査読有り

    Kotani, Y., Senba, Y., Toyoki, K., Billington, D., Okazaki, H., Yasui, A., Ueno, W., Ohashi, H., Hirosawa, S., Shiratsuchi, Y., Nakamura, T.

    Journal of Synchrotron Radiation 25 (5) 1444-1449 2018年

    出版者・発行元:International Union of Crystallography (IUCr)

    DOI: 10.1107/S1600577518009177  

    eISSN:1600-5775

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    For the purpose of imaging element- and shell-specific magnetic distributions under high magnetic fields, a scanning soft X-ray microscope has been developed at beamline BL25SU, SPring-8, Japan. The scanning X-ray microscope utilizes total electron yield detection of absorbed circularly polarized soft X-rays in order to observe magnetic domains through the X-ray magnetic circular dichroism effect. Crucially, this system is equipped with an 8 T superconducting magnet. The performance and features of the present system are demonstrated by magnetic domain observations of the fractured surface of a Nd<sub>14.0</sub>Fe<sub>79.7</sub>Cu<sub>0.1</sub>B<sub>6.2</sub>sintered magnet.

  5. Unveiling the origin of the large coercivity in (Nd, Dy)-Fe-B sintered magnets

    Xin Tang, Jiangnan Li, Hossein Sepehri-Amin, Anton Bolyachkin, Andres Martin-Cid, Shintaro Kobayashi, Yoshinori Kotani, Motohiro Suzuki, Asako Terasawa, Yoshihiro Gohda, Tadakatsu Ohkubo, Tetsuya Nakamura, Kazuhiro Hono

    NPG Asia Materials 15 (1) 2023年9月29日

    出版者・発行元:Springer Science and Business Media LLC

    DOI: 10.1038/s41427-023-00498-5  

    eISSN:1884-4057

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    Abstract Nd-Fe-B-based permanent magnets are widely used for energy conversion applications. However, their usage at elevated temperatures is difficult due to the relatively low coercivity (H<sub>c</sub>) with respect to the anisotropy field (H<sub>A</sub>) of the Nd<sub>2</sub>Fe<sub>14</sub>B compound, which is typically 0.2H<sub>A</sub>. In this work, we found that the coercivity of an (Nd<sub>0.8</sub>Dy<sub>0.2</sub>)-Fe-B sintered magnet could reach 0.4H<sub>A</sub>, which was twice as high as the H<sub>c</sub>/H<sub>A</sub> of its Dy-free counterpart. Detailed microstructural characterizations, density functional theory and micromagnetic simulations showed that the large value of coercivity, H<sub>c</sub> = 0.4H<sub>A</sub>, originated not only from the enhanced H<sub>A</sub> of the main phase (intrinsic factor) but also from the reduced magnetization of the thin intergranular phase (extrinsic factor). The latter was attributed to the dissolution of 4 at.% Dy in the intergranular phase that anti-ferromagnetically coupled with Fe. The reduction in the magnetization of the intergranular phase resulted in a change in the angular dependence of coercivity from the Kondorsky type for the Dy-free magnet to the Stoner–Wohlfarth-like shape for the Dy-containing magnet, indicating that the typical pinning-controlled coercivity mechanism began to show nucleation features as the magnetization of the intergranular phase was reduced by Dy substitution.

  6. Demagnetization processes of Nd-Fe-B sintered magnets and ferrite magnets as demonstrated by soft X-ray magnetic circular dichroism microscopy

    Yutaka Matsuura, Keisuke Ishigami, Ryuji Tamura, Tetsuya Nakamura

    Journal of Magnetism and Magnetic Materials 579 170854-170854 2023年8月

    出版者・発行元:Elsevier BV

    DOI: 10.1016/j.jmmm.2023.170854  

    ISSN:0304-8853

  7. Understanding the Coercivity of Ga-Containing Nd-Fe-B Sintered Magnets from Feature Extraction and Selection of X-Ray Diffraction Patterns via Dimension Reduction and Sparse Modeling

    Keisuke Ishigami, Tomoyuki Onuma, Akira Kato, Masao Yano, Tetsuya Shoji, Tetsuya Nakamura, Satoshi Okamoto

    2023 IEEE International Magnetic Conference (INTERMAG) 2023年5月

    出版者・発行元:IEEE

    DOI: 10.1109/intermag50591.2023.10265093  

  8. Bulk Rashba-Type Spin Splitting in Non-Centrosymmetric Artificial Superlattices

    Woo Seung Ham, Thi Huynh Ho, Yoichi Shiota, Tatsuya Iino, Fuyuki Ando, Tetsuya Ikebuchi, Yoshinori Kotani, Tetsuya Nakamura, Daisuke Kan, Yuichi Shimakawa, Takahiro Moriyma, Eunji Im, Nyun Jong Lee, Kyoung Whan Kim, Soon Cheol Hong, Sonny H. Rhim, Teruo Ono, Sanghoon Kim

    Advanced Science 10 (12) 2023年4月

    DOI: 10.1002/advs.202206800  

    eISSN:2198-3844

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    Spin current, converted from charge current via spin Hall or Rashba effects, can transfer its angular momentum to local moments in a ferromagnetic layer. In this regard, the high charge-to-spin conversion efficiency is required for magnetization manipulation for developing future memory or logic devices including magnetic random-access memory. Here, the bulk Rashba-type charge-to-spin conversion is demonstrated in an artificial superlattice without centrosymmetry. The charge-to-spin conversion in [Pt/Co/W] superlattice with sub-nm scale thickness shows strong W thickness dependence. When the W thickness becomes 0.6 nm, the observed field-like torque efficiency is about 0.6, which is an order larger than other metallic heterostructures. First-principles calculation suggests that such large field-like torque arises from bulk-type Rashba effect due to the vertically broken inversion symmetry inherent from W layers. The result implies that the spin splitting in a band of such an ABC-type artificial SL can be an additional degree of freedom for the large charge-to-spin conversion.

  9. Post-acquisition upsampling method for scanning x-ray microscopy

    Hiroyuki Ohsumi, Yoshinori Fujikawa, Lihua Liu, Yoshinori Kotani, Tetsuya Nakamura

    Review of Scientific Instruments 2023年3月1日

    DOI: 10.1063/5.0098245  

  10. Multimodal analysis of Zr substitution effects on magnetic and crystallographic properties in (Sm1−Zr )(Fe0.8Co0.2)12 compounds with ThMn12 structure

    S. Kobayashi, D. Ogawa, X.D. Xu, Y.K. Takahashi, A. Martin-Cid, K. Ishigami, Y. Kotani, M. Suzuki, T. Yoshioka, H. Tsuchiura, H. Sepehri-Amin, T. Ohkubo, K. Hono, S. Hirosawa, T. Nakamura

    Acta Materialia 242 118454-118454 2023年1月

    出版者・発行元:Elsevier BV

    DOI: 10.1016/j.actamat.2022.118454  

    ISSN:1359-6454

  11. Real picture of magnetic domain dynamics along the magnetic hysteresis curve inside an advanced permanent magnet

    Makoto Takeuchi, Motohiro Suzuki, Shintaro Kobayashi, Yoshinori Kotani, Tetsuya Nakamura, Nobuaki Kikuchi, Anton Bolyachkin, Hossein Sepehri-Amin, Tadakatsu Ohkubo, Kazuhiro Hono, Yasuhiro Une, Satoshi Okamoto

    NPG Asia Materials 14 (1) 2022年12月

    出版者・発行元:Springer Science and Business Media LLC

    DOI: 10.1038/s41427-022-00417-0  

    ISSN:1884-4049

    eISSN:1884-4057

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    Abstract In the long history of permanent magnet research for more than 100 years, three-dimensional magnetic microscopy has been eagerly awaited to elucidate the origin of the magnetic hysteresis of permanent magnets. In this study, we succeeded in observing the three-dimensional magnetic domain structure of an advanced high-coercivity Nd-Fe-B-based permanent magnet throughout the magnetic hysteresis curve using a recently developed hard X-ray magnetic tomography technique. Focused-ion-beam-based three-dimensional scanning electron microscopy was employed to study the relationship between the observed magnetic domains and the microstructure of the magnet for the same observing volume. Thermally demagnetized and coercivity states exhibit considerably different magnetic domain structures but show the same periodicity of 2.3 μm, indicating that the characteristic length of the magnetic domain is independent of the magnetization states. Further careful examination revealed some unexpected magnetic domain behaviors, such as running perpendicular to the magnetic easy axis and reversing back against the magnetic field. These findings demonstrate a wide variety of real magnetic domain behaviors along the magnetic hysteresis inside a permanent magnet.

  12. Magnetic refrigeration material operating at a full temperature range required for hydrogen liquefaction

    Xin Tang, H. Sepehri-Amin, N. Terada, A. Martin-Cid, I. Kurniawan, S. Kobayashi, Y. Kotani, H. Takeya, J. Lai, Y. Matsushita, T. Ohkubo, Y. Miura, T. Nakamura, K. Hono

    Nature Communications 13 (1) 2022年12月

    出版者・発行元:Springer Science and Business Media LLC

    DOI: 10.1038/s41467-022-29340-2  

    eISSN:2041-1723

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    Abstract Magnetic refrigeration (MR) is a key technique for hydrogen liquefaction. Although the MR has ideally higher performance than the conventional gas compression technique around the hydrogen liquefaction temperature, the lack of MR materials with high magnetic entropy change in a wide temperature range required for the hydrogen liquefaction is a bottle-neck for practical applications of MR cooling systems. Here, we show a series of materials with a giant magnetocaloric effect (MCE) in magnetic entropy change (-∆S<sub>m</sub> &gt; 0.2 J cm<sup>−3</sup>K<sup>−1</sup>) in the Er(Ho)Co<sub>2</sub>-based compounds, suitable for operation in the full temperature range required for hydrogen liquefaction (20-77 K). We also demonstrate that the giant MCE becomes reversible, enabling sustainable use of the MR materials, by eliminating the magneto-structural phase transition that leads to deterioration of the MCE. This discovery can lead to the application of Er(Ho)Co<sub>2</sub>-based alloys for the hydrogen liquefaction using MR cooling technology for the future green fuel society.

  13. Synthesis of superparamagnetic Co–Pt nanoparticle in Pyrococcus furiosus virus-like particle crystal

    Makoto Taniguchi, Akifumi Higashiura, Naoto Kobayashi, Daisuke Kanda, Kakeru Tagata, Ryota Fukunishi, Yasunori Yoshikawa, Emi Kuromatsu, Noriaki Kishida, Yoshinori Kotani, Kentaro Toyoki, Tetsuya Nakamura, Ryoichi Nakatani, Atsushi Nakagawa, Yu Shiratsuchi

    Journal of Physics and Chemistry of Solids 169 110840-110840 2022年6月

    出版者・発行元:Elsevier BV

    DOI: 10.1016/j.jpcs.2022.110840  

    ISSN:0022-3697

  14. Control of perpendicular magnetic anisotropy at the Fe/MgO interface by phthalocyanine insertion

    Shoya Sakamoto, Edward Jackson, Takeshi Kawabe, Takuya Tsukahara, Yoshinori Kotani, Kentaro Toyoki, Emi Minamitani, Yoshio Miura, Tetsuya Nakamura, Atsufumi Hirohata, Shinji Miwa

    Physical Review B 105 (18) 2022年5月13日

    出版者・発行元:American Physical Society (APS)

    DOI: 10.1103/physrevb.105.184414  

    ISSN:2469-9950

    eISSN:2469-9969

  15. Soft X-ray absorption spectroscopy and magnetic circular dichroism under pulsed high magnetic field of Ni-Co-Mn-In metamagnetic shape memory alloy

    Umetsu, R.Y., Yasumura, H., Narumi, Y., Kotani, Y., Nakamura, T., Nojiri, H., Kainuma, R.

    Journal of Alloys and Compounds 890 2022年

    DOI: 10.1016/j.jallcom.2021.161590  

    ISSN:0925-8388

  16. Magnetic Domain Structure Observation for Initial Magnetization and Demagnetization Processes of a Nd-Fe-B Hot-Deformed Magnet Using Soft X-ray Magnetic Circular Dichroism Microscopy

    M. Takeuchi, T. Yomogita, N. Kikuchi, K. Toyoki, S. Kobayashi, Y. Kotani, T. Nakamura, K. Hioki, S. Okamoto

    Journal of the Japan Institute of Metals and Materials 86 (1) 1-7 2022年1月1日

    出版者・発行元:Japan Institute of Metals

    DOI: 10.2320/jinstmet.j2021041  

    ISSN:0021-4876

    eISSN:1880-6880 2433-7501

  17. X-ray study of ferroic octupole order producing anomalous Hall effect

    Motoi Kimata, Norimasa Sasabe, Kensuke Kurita, Yuichi Yamasaki, Chihiro Tabata, Yuichi Yokoyama, Yoshinori Kotani, Muhammad Ikhlas, Takahiro Tomita, Kenta Amemiya, Hiroyuki Nojiri, Satoru Nakatsuji, Takashi Koretsune, Hironori Nakao, Taka hisa Arima, Tetsuya Nakamura

    Nature Communications 12 (1) 2021年12月

    DOI: 10.1038/s41467-021-25834-7  

    eISSN:2041-1723

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    Recently found anomalous Hall, Nernst, magnetooptical Kerr, and spin Hall effects in the antiferromagnets Mn3X (X = Sn, Ge) are attracting much attention for spintronics and energy harvesting. Since these materials are antiferromagnets, the origin of these functionalities is expected to be different from that of conventional ferromagnets. Here, we report the observation of ferroic order of magnetic octupole in Mn3Sn by X-ray magnetic circular dichroism, which is only predicted theoretically so far. The observed signals are clearly decoupled with the behaviors of uniform magnetization, indicating that the present X-ray magnetic circular dichroism is not arising from the conventional magnetization. We have found that the appearance of this anomalous signal coincides with the time reversal symmetry broken cluster magnetic octupole order. Our study demonstrates that the exotic material functionalities are closely related to the multipole order, which can produce unconventional cross correlation functionalities.

  18. Effect of hydrogenation-disproportionation-desorption-recombination powder processing on the demagnetization process of Nd-Fe-B sintered magnets analyzed by soft X-ray magnetic circular dichroism microscopy

    A. Martin-Cid, T. Kawahara, S. Kobayashi, K. Toyoki, D. Billington, Y. Kotani, H. Kubo, Y. Une, T. Iriyama, M. Sagawa, T. Nakamura

    Journal of Magnetism and Magnetic Materials 538 2021年11月15日

    DOI: 10.1016/j.jmmm.2021.168308  

    ISSN:0304-8853

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    The demagnetization process of a variety of Nd-Fe-B-based magnets produced using different manufacturing techniques are studied by soft X-ray magnetic circular dichroism microscopy. The four magnets studied include a hot deformed magnet, sintered magnets produced from either a N2 jet-milled or a He jet-milled fine powder, and a magnet produced by hydrogenation-disproportionation-desorption-recombination (HDDR) followed by He jet-milling. The coercivity of the HDDR processed magnet is lower than the magnets produced with N2 jet-milled powder even though the size of the grains is smaller. By following the magnetic domain reversal behavior during the demagnetization process, it was found that, while the magnets produced with N2 jet-milled powder and the hot deformed magnet presents a predominance of the reversed magnetic domain propagation, in the HDDR processed magnet the nucleation of individual grains occurs before the reversed magnetic domains propagate. This behavior is associated with a decreased nucleation field of each grain.

  19. 光源の違いによる走査型X線後方散乱ラウエ顕微鏡の性能比較 査読有り

    隅谷 和嗣, 豊木 研太郎, 石上 啓介, 梶原 堅太郎, 中村 哲也, 田村 隆治, 木田 潤一郎, 加藤 涼, 松浦 裕, 米山 祐輔, 笹田 星児, 北岸 浩一, 加藤 千景

    SPring-8/SACLA利用研究成果集 9 (6) 405-410 2021年10月

    DOI: 10.18957/rr.9.6.405  

  20. Diagram of constituent crystalline phases in a Nd–Fe–B–Cu sintered magnet by in-situ high-temperature synchrotron X-ray diffraction and its thermodynamic interpretation

    S. Kobayashi, T. Abe, A. Martín-Cid, S. Kawaguchi, M. Suzuki, S. Hirosawa, T. Nakamura

    Journal of Alloys and Compounds 162188-162188 2021年9月

    出版者・発行元:Elsevier BV

    DOI: 10.1016/j.jallcom.2021.162188  

    ISSN:0925-8388

  21. High-field soft-x-ray dichroism of a hard ferrimagnet with easy-plane anisotropy

    Sh Yamamoto, D. I. Gorbunov, I. F. Diaz-Ortega, A. Miyata, T. Kihara, Y. Kotani, T. Nakamura, N. V. Mushnikov, A. V. Andreev, H. Nojiri, J. Wosnitza

    Physical Review B 104 (6) 2021年8月1日

    DOI: 10.1103/PhysRevB.104.064405  

    ISSN:2469-9950

    eISSN:2469-9969

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    We performed soft x-ray spectroscopic studies of the ferrimagnet TbFe5Al7 with strong easy-plane anisotropy in pulsed magnetic fields up to 29 T along with bulk magnetization and magnetostriction measurements. We observed pronounced amplitude changes of x-ray magnetic circular dichroism and x-ray absorption spectra at the field-induced magnetic transition. This microscopically evidences the simultaneous rotation of the Tb 4f and Fe 3d magnetic moments from a collinear ferrimagnetic order along the [100] axis to a state with the moments close to [010], the other easy-axis direction of the tetragonal lattice in magnetic fields applied along the [100] axis. We determined the magnetic-anisotropy constant of TbFe5Al7 by simulating the high-field macro- and microscopic magnetization process using a two-sublattice model.

  22. Alignment and Angular Dependences of Coercivity for (Sm, Ce)₂(Co, Fe, Cu, Zr)₁₇ Magnets

    Matsuura Yutaka, Tamura Ryuji, Ishigami Keisuke, Sumitani Kazushi, Kajiwara Kentaro, Nakamura Tetsuya

    Materials transactions 62 (7) 1009-1012 2021年7月

    出版者・発行元:The Japan Institute of Metals and Materials ; 2001-

    ISSN:1345-9678

  23. Phase relations and extrinsic magnetic properties of Sm–(Fe,Co)–Ti–(Ga)-based alloys for ThMn12-type permanent magnets

    A.K. Srinithi, H. Sepehri-Amin, Xin Tang, P. Tozman, J. Li, J. Zhang, S. Kobayashi, T. Ohkubo, T. Nakamura, K. Hono

    Journal of Magnetism and Magnetic Materials 529 167866-167866 2021年7月

    出版者・発行元:Elsevier {BV}

    DOI: 10.1016/j.jmmm.2021.167866  

    ISSN:0304-8853

  24. Presence of X-Ray Magnetic Circular Dichroism Signal for Zero-Magnetization Antiferromagnetic State

    Norimasa Sasabe, Motoi Kimata, Tetsuya Nakamura

    Physical Review Letters 126 (15) 2021年4月16日

    出版者・発行元:American Physical Society (APS)

    DOI: 10.1103/PhysRevLett.126.157402  

    ISSN:0031-9007

    eISSN:1079-7114

  25. Strain-induced modulation of temperature characteristics in ferrimagnetic Tb–Fe films

    Shinya Ota, Pham Van Thach, Hiroyuki Awano, Akira Ando, Kentaro Toyoki, Yoshinori Kotani, Tetsuya Nakamura, Tomohiro Koyama, Daichi Chiba

    Scientific Reports 11 (1) 2021年3月

    DOI: 10.1038/s41598-021-85642-3  

    eISSN:2045-2322

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    This study investigates the effect of strain on the compensation temperature of ferrimagnetic Tb–Fe films formed on a flexible substrate. The compensation temperature is determined by the anomalous Hall measurement, and an application of 1.2% tensile strain reduces the compensation temperature by 12 K. X-ray magnetic circular dichroism reveals that approximately 5% of Fe magnetic moment and approximately 1% of Tb magnetic moment are reduced by an application of 0.9% tensile strain at the room temperature. To understand the greater reduction in Fe magnetization compared with that in Tb and the compensation temperature reduction simultaneously, a model applying molecular field theory is analyzed. Changes in three types of exchange coupling between Fe and Tb atoms are speculated to be caused by the strain.

  26. MnFeNiGeSi high-entropy alloy with large magnetocaloric effect 査読有り

    Jia Yan Law, Luis M. Moreno-Ramírez, Álvaro Díaz-García, Andrés Martín-Cid, Shintaro Kobayashi, Shogo Kawaguchi, Tetsuya Nakamura, Victorino Franco

    Journal of Alloys and Compounds 855 157424-157424 2021年2月

    出版者・発行元:Elsevier BV

    DOI: 10.1016/j.jallcom.2020.157424  

    ISSN:0925-8388

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    The magnetocaloric effect of high-entropy alloys (HEAs) due to a second-order phase transition exhibits limited response. A significant improvement is obtained in Mn Fe Ni Ge Si HEA as it exhibits a magneto-structural first-order phase transition. Its isothermal entropy change of 7.3 J kg K (for 2.5 T) is the largest reported to date for rare earth-free HEAs. The alloy composition was found by a directed search that starts from a medium entropy alloy with the desired transformation combined with isostructural substitutions. Our findings demonstrate the existence of HEA with magneto-structural phase transition and that HEAs have promising potential as high-performance magnetocaloric materials. 22 . 3 22 . 2 22.2 16.65 16.65 −1 −1

  27. Relationship between the microstructure, local magnetism and coercivity in Ga-containing Nd-Fe-B sintered magnets 査読有り

    David Billington, Hiroyuki Okazaki, Kentaro Toyoki, Yoshinori Kotani, Yukio Takada, Takashi Sato, Yuji Kaneko, Akira Kato, Taisuke T. Sasaki, Tadakatsu Ohkubo, Kazuhiro Hono, Tetsuya Nakamura

    Acta Materialia 205 116517-116517 2021年2月

    出版者・発行元:Elsevier BV

    DOI: 10.1016/j.actamat.2020.116517  

    ISSN:1359-6454

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    The crystalline phases that comprise the bulk microstructure of an isotropic Ga-containing Nd-Fe-B sintered magnet are identified by in situ elevated-temperature x-ray diffraction for temperatures between 25 and 800 C. Comparing the temperature-dependent volume fractions of the crystalline phases with the coercivity as a function of annealing temperature reveals that the large coercivity enhancements are remarkably well-correlated with the existence of a crystalline Nd (Fe,Ga) phase. Scanning soft x-ray absorption microscopy measurements are used to directly observe the distribution of Fe and Nd in anisotropic as-sintered and optimally-annealed samples and demonstrate that the surface microstructure is similar to the bulk. Fe L -edge x-ray magnetic circular dichroism measurements are used to directly map the demagnetization process in the fractured surfaces of anisotropic as-sintered and optimally-annealed samples. In the as-sintered sample, the demagnetization curves of compositionally different regions all have the same shape but with a maximum magnetic signal that only depends on the Fe content within the probing depth of the x-ray absorption measurements. In the optimally-annealed sample, the demagnetization curves from compositionally different regions have rather different shapes and the exposed Nd Fe B grains without any grain boundary coverage have much lower coercivity than those with. This provides evidence that the grain boundary phase that forms upon annealing is able to protect the Nd Fe B grains from magnetization reversal by exchange-decoupling the Nd Fe B grains. ∘ 6 14 3 2 14 2 14 2 14

  28. Element-specific field-induced spin reorientation and tetracritical point in MnCr2S4

    Sh. Yamamoto, H. Suwa, T. Kihara, T. Nomura, Y. Kotani, T. Nakamura, Y. Skourski, S. Zherlitsyn, L. Prodan, V. Tsurkan, H. Nojiri, A. Loidl, J. Wosnitza

    Physical Review B 103 (2) 2021年1月25日

    出版者・発行元:American Physical Society (APS)

    DOI: 10.1103/PhysRevB.103.L020408  

    ISSN:2469-9950

    eISSN:2469-9969

  29. Bulk and element-specific magnetism of medium-entropy and high-entropy Cantor-Wu alloys 査読有り

    D. Billington, A. D. N. James, E. I. Harris-Lee, D. A. Lagos, D. O'Neill, N. Tsuda, K. Toyoki, Y. Kotani, T. Nakamura, H. Bei, S. Mu, G. D. Samolyuk, G. M. Stocks, J. A. Duffy, J. W. Taylor, S. R. Giblin, S. B. Dugdale

    Physical Review B 102 (17) 2020年11月5日

    出版者・発行元:American Physical Society (APS)

    DOI: 10.1103/physrevb.102.174405  

    ISSN:2469-9950

    eISSN:2469-9969

  30. Time-resolved imaging of an operating hard-disk-drive write head using nano-beam x-ray magnetic circular dichroism 査読有り

    Hirofumi Suto, Akira Kikitsu, Yoshinori Kotani, Tomoyuki Maeda, Kentaro Toyoki, Hitoshi Osawa, Nobuaki Kikuchi, Satoshi Okamoto, Tetsuya Nakamura

    Journal of Applied Physics 128 (13) 2020年10月7日

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/5.0022571  

    ISSN:0021-8979

    eISSN:1089-7550

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    We studied the dynamic magnetization behavior of a hard-disk-drive (HDD) write head by using nano-beam x-ray magnetic circular dichroism (XMCD). The write head was operated by applying a square-wave write current with a frequency of 211.9MHz to the coil of the write head, which was in synchronization with the fivefold frequency of the x-ray pulses. Snapshot images of the magnetization on the air-bearing surface of the write head were obtained with spatial and time resolutions of 100nm and 50ps, respectively, and temporal changes in the magnetization of the main pole and the shield were observed. When a square-wave write current with a transition time of 0.2ns was applied, the magnetization reversal of the main pole was completed in 0.7ns, and this reversal time was determined by the dynamic property of the write head. During the main pole reversal, the shield area showed spatially non-uniform magnetization patterns, and its response was slower than that of the main pole. These results show that the XMCD measurement setup developed in this study is a powerful tool for understanding the dynamic behavior of an HDD write head and contributes to the development of higher capacity HDDs.

  31. Orbital-dependent electric field effect on magnetism in ultrathin cobalt 査読有り

    Kihiro T. Yamada, Yoichi Shiota, Tomohiro Koyama, Yoshinori Kotani, Kentaro Toyoki, Hayato Mizuno, Fuyuki Ando, Kohji Nakamura, Tetsuya Nakamura, Daichi Chiba, Teruo Ono

    Physical Review B 102 (10) 2020年9月17日

    出版者・発行元:American Physical Society (APS)

    DOI: 10.1103/physrevb.102.100407  

    ISSN:2469-9950

    eISSN:2469-9969

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    Electric field modulations of magnetism in ferromagnetic metals are in general ascribed to the electric field effects on the orbitals. However, a direct observation of the electric-field-induced changes in the orbital states of a ferromagnetic metal is lacking. In this Rapid Communication, we demonstrate that an electric field applied to an ultrathin Co film can change the electron occupations according to the orbitals, combining x-ray absorption and x-ray magnetic circularly dichroism spectroscopies with the sum rules. Under a positive electric field, the d(xz(yz))-occupied states decrease mainly via the modification of orbital hybridizations, while the d(z2) -occupied state increases. The changes in the d(xz) and d(yz) states dominantly alter the Curie temperature.

  32. Effects of texture on lattice constants of Nd2Fe14B and their relationship with internal stress in Nd-Fe-B permanent magnets 査読有り

    S. Kobayashi, A. Martín-Cid, K. Toyoki, H. Okazaki, S. Kawaguchi, S. Hirosawa, T. Nakamura

    Physical Review Materials 4 (9) 2020年9月14日

    出版者・発行元:American Physical Society (APS)

    DOI: 10.1103/physrevmaterials.4.094405  

    eISSN:2475-9953

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    Although crystallographic properties are considered to be intrinsic, several studies have reported significant different values for the lattice constants of the Nd2Fe14B phase. In this study, by analyzing rod-shaped isotropic (randomly oriented) and anisotropic (c-axis oriented) Nd-Fe-B bulk-sintered magnets, their powdered counterparts, and powder made from grinding a single crystal, we experimentally demonstrate that the lattice constants of the Nd2Fe14B phase in the ferromagnetic ordering state depend on the sample texture. The temperature dependence of the lattice constants was investigated by focusing on their expansion associated with ferromagnetic ordering, that is, the spontaneous linear expansion along the a-axis (λa) and c-axis (λc). The λa value of the isotropic (anisotropic) bulk-sintered magnets at 105 K is 10% (2%) smaller while the λc value is 130% (40%) greater than that of the powdered single crystal. These results indicate the presence of an internal stress perpendicular to the c-axis in the isotropic and anisotropic bulk-sintered magnets. In addition, we observed that the ratios of the length along the a-axis to that along the c-axis (c/a) for the various Nd-Fe-B magnets as well as those reported previously are correlated to the sample texture. In other words, the c/a values of the sintered magnets are greater than those of the powdered samples. This result suggests that the sample texture and hence the internal stress has a determining effect on the lattice constants.

  33. Voltage-controlled magnetic anisotropy in an ultrathin nickel film studied by operando x-ray magnetic circular dichroism spectroscopy 査読有り

    Risa Miyakaze, Shoya Sakamoto, Takeshi Kawabe, Takuya Tsukahara, Yoshinori Kotani, Kentaro Toyoki, Tetsuya Nakamura, Minori Goto, Yoshishige Suzuki, Shinji Miwa

    Physical Review B 102 (1) 2020年7月13日

    出版者・発行元:American Physical Society (APS)

    DOI: 10.1103/physrevb.102.014419  

    ISSN:2469-9950

    eISSN:2469-9969

  34. Magnetization reversal of (Sm, Ce)2(Co, Fe, Cu, Zr)17 magnets as per soft x-ray magnetic circular dichroism microscopy 査読有り

    Yutaka Matsuura, Ryo Maruyama, Ryo Kato, Ryuji Tamura, Keisuke Ishigami, Kazushi Sumitani, Kentaro Kajiwara, Tetsuya Nakamura

    Applied Physics Letters 117 (2) 2020年7月13日

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/5.0005635  

    ISSN:0003-6951

    eISSN:1077-3118

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    We investigated magnetization reversal of (Sm, Ce)(2)(Co, Fe, Cu, Zr)(17) magnets as per x-ray magnetic circular dichroism microscopy. Magnetization reversal initially occurs at the ferromagnetic grain boundaries or in the vicinity of nonmagnetic Sm oxides. As the demagnetization field increases after magnetization reversal, the reversal region extends into the grain from these areas by the magnetic domain wall motion. Energy-dispersive x-ray analysis using an electron probe micro-analyzer shows that, at the grain boundaries, the Fe concentration is higher and the Cu concentration is lower compared to that inside of the grains; and concentrations of Sm, Co, Fe, and Cu vary in the vicinity of Sm oxides. By measuring the Co L-3 absorption intensity, we verified that local coercivities in these areas are very low compared to those inside of the grain. These results imply that the magnetization reversal that occurs in these areas is induced by the variation in the composition. The results obtained in our research will be useful for improving the magnetic properties of Sm-Co magnets. (C) 2020 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

  35. Direct Evidence of Simultaneous Reversal of Ferrimagnetically Coupled Sm 4f and Mn 3d Angular Momenta in SmMnO3 査読有り

    J.-S. Jung, T. Nakamura, Y. Wakabayashi, T. Kimura

    Journal of the Korean Physical Society 76 (10) 904-910 2020年5月

    出版者・発行元:Korean Physical Society

    DOI: 10.3938/jkps.76.904  

    ISSN:0374-4884

    eISSN:1976-8524

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    Using the soft X-ray magnetic circular dichroism (XMCD) technique, we investigated the magnetic states of the Sm 4f and the Mn 3d moments in a Néel N-type ferrimagnet, SmMnO3, which exhibits a striking magnetocapacitive effect around the compensation temperature (Tcomp ≈ 9.4 K). The XMCD results show that the Sm 4f and the Mn 3d moments were always aligned antiparallel to each other and that, upon sweeping a magnetic field, the angular momenta of Sm 4f and Mn 3d were simultaneously reversed at the field where the magnetocapacitive effect was observed. This indicates that the magnetocapacitive effect of SmMnO3 is induced by a simultaneous reversal of Sm 4f and Mn 3d angular momenta, i.e., magnetization reversal. We discuss a plausible origin of the magnetocapacitive effect in terms of the p-d hybridization mechanism.

  36. Robust magnetic domain of Pt/Co/Au/Cr2O3/Pt stacked films with a perpendicular exchange bias 査読有り

    Yu Shiratsuchi, Saori Yoshida, Hiroaki Yoshida, Yoshinori Kotani, Kentaro Toyoki, Ryoichi Nakatani, Chiharu Mitsumata, Tetsuya Nakamura

    Journal of Applied Physics 127 (15) 153902-153902 2020年4月21日

    出版者・発行元:{AIP} Publishing

    DOI: 10.1063/5.0002240  

    ISSN:0021-8979

    eISSN:1089-7550

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    © 2020 Author(s). Magnetic domain pattern and magnetic domain wall motion are particularly important to understand the magnetization process. Here, we investigated the magnetization process of perpendicularly exchange-biased Pt/Co/Au/Cr2O3/Pt stacked films based on observations of the magnetic domain. In particular, in contrast to previous studies which use fully exchange-biased state, we used the bi-exchange-biased state. We found that the magnetic domain pattern at the remanent state was robust against magnetic-field cycling, which is relevant to the absence of the training effect. The magnetization process was followed by domain wall propagation in the increasing branch of the magnetization curve. In the decreasing branch, both nucleation of the reversed domain and domain wall propagation were involved. The former was accompanied by latency, suggesting that thermal activation played a significant role in the nucleation of the reversed domain.

  37. Magnetic Microscopy Using a Circularly Polarized Hard-X-ray Nanoprobe at SPring-8 査読有り

    M. Suzuki, H. Yumoto, T. Koyama, H. Yamazaki, T. Takeuchi, N. Kawamura, M. Mizumaki, H. Osawa, Y. Kondo, J. Ariake, A. Yasui, Y. Kotani, N. Tsuji, T. Nakamura, S. Hirosawa, K. T. Yamada, S. Kim, K.-J. Kim, M. Ishibashi, T. Ono, H. Ohashi

    Synchrotron Radiation News 33 (2) 4-11 2020年4月1日

    出版者・発行元:Informa UK Limited

    DOI: 10.1080/08940886.2020.1725795  

    ISSN:0894-0886

    eISSN:1931-7344

  38. Magnetization manipulation induced by nonlocal spin injection from a perpendicular spin polarizer: nano-beam X-ray MCD study using an order-sorting-aperture collection method 査読有り

    Hirofumi Suto, Nobuaki Kikuchi, Satoshi Okamoto, Kentaro Toyoki, Yoshinori Kotani, Tetsuya Nakamura

    Applied Physics Express 13 (4) 043002-043002 2020年4月1日

    出版者・発行元:IOP Publishing

    DOI: 10.35848/1882-0786/ab7bcb  

    ISSN:1882-0778

    eISSN:1882-0786

  39. Critical behavior of perpendicular exchange bias in Ru/Pd/Co/Pt/Cr<inf>2</inf>O<inf>3</inf>/Pd stacked films 査読有り

    Yu Shiratsuchi, Motohiro Suzuki, Kentaro Toyoki, Kohei Wakatsu, Takashi Nishimura, Tetsuya Nakamura, Ryoichi Nakatani

    Physica B: Condensed Matter 583 2020年4月

    DOI: 10.1016/j.physb.2020.412053  

    ISSN:0921-4526

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    © 2020 Elsevier B.V. The proximity effect in a heavy metal attached to a ferromagnetic (FM) layer results in varied interface magnetism. In this study, we investigated the critical behavior of the perpendicular exchange bias in a Ru/Pd/Co/Pt/Cr2O3/Pd stacked film, with focus on the influence of the Pt spacer layer. The apparent critical exponent β increases with increasing Pt thickness. We discussed the possible mechanism from the perspective of the induced magnetic moment of Pt and interfacial exchange coupling. The former was explored based on X-ray magnetic circular dichroism, which revealed that the magnetic moment of Pt was almost temperature-independent within the studied temperature regime. This suggests that the interfacial FM moment is stable. The latter, i.e., the reduction of the interfacial exchange coupling by the Pt spacer layer, is a possible cause of the increase in β, as theoretically predicted.

  40. Imaging of transient magnetization dynamics of Co/Pt multilayer dots with X-ray magnetic circular dichroism excited by microwaves 査読有り

    N. Kikuchi, T. Yomogita, K. Sato, S. Okamoto, O. Kitakami, H. Osawa, M. Suzuki, K. Toyoki, Y. Kotani, T. Nakamura

    Japanese Journal of Applied Physics 59 (SE) SEED03-SEED03 2020年4月1日

    出版者・発行元:IOP Publishing

    DOI: 10.35848/1347-4065/ab6cb1  

    ISSN:0021-4922

    eISSN:1347-4065

  41. Giant Anomalous Hall Conductivity at the Pt/Cr 2 O 3 Interface 査読有り

    Takahiro Moriyama, Yu Shiratsuchi, Tatsuya Iino, Hikaru Aono, Motohiro Suzuki, Tetsuya Nakamura, Yoshinori Kotani, Ryoichi Nakatani, Kohji Nakamura, Teruo Ono

    Physical Review Applied 2020年3月20日

    DOI: 10.1103/PhysRevApplied.13.034052  

  42. Coercivity Mechanism of Ga-Doped Nd-Fe-B Sintered Magnets

    Yutaka Matsuura, Tetsuya Nakamura, Keisuke Ishigami, Kentaro Kajiwara, Kazushi Sumitani, Ryuji Tamura, Masahiro Nagae, Kozo Osamura

    IEEE TRANSACTIONS ON MAGNETICS 55 (12) 2019年12月

    出版者・発行元:IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/TMAG.2019.2940205  

    ISSN:0018-9464

    eISSN:1941-0069

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    The alignment dependence and angular dependence of coercivity (ALDC and ANDC, respectively) of aligned and isotropically aligned Ga-doped Nd14.79Ga0.57B5,24Co1.11Febal sintered magnets were analyzed, and the results were compared with those of ferrite magnets, which were reported in our previous paper. The coercivity of Ga-doped Nd-Fe-B magnets decreases as alignment improves. The ALDC of this magnet is similar to that of ferrite magnets. The angle of the magnetization-reversal area (AMRA) of the aligned Ga-doped magnets has at coercivity an angular tilt of 41.4 degrees, which is wider than that of the ferrite magnets. The ANDC of Ga-doped Nd-Fe-B sintered magnets displays similar behavior with that of ferrite magnets but is slightly lower than that of ferrite magnets, which is expected from AMRA of Ga-doped Nd-Fe-B sintered magnets. These results support our proposed coercivity mechanism; specifically, the magnetic domain walls are pinned at grains with tilted easy magnetization directions or c-axis tilted from the easy magnetization of the magnet. When the magnetic domain walls are de-pinned from the pinning sites, they jump through several grains, thereby determining the coercivity.

  43. Influence of magnetostriction on the lattice constants of the secondary phases in Nd-Fe-B sintered magnets studied by synchrotron X-ray diffraction 査読有り

    Shintaro Kobayashi, Andrés Martín-Cid, Kentaro Toyoki, Hiroyuki Okazaki, Satoshi Hirosawa, Tetsuya Nakamura

    AIP Advances 9 (12) 125154-125154 2019年12月1日

    出版者・発行元:AIP Publishing

    DOI: 10.1063/1.5129849  

    eISSN:2158-3226

  44. Temperature dependent magnetization reversal process of a Ga-doped Nd-Fe-B sintered magnet based on first-order reversal curve analysis 査読有り

    Satoshi Okamoto, Kazunori Miyazawa, Takahiro Yomogita, Nobuaki Kikuchi, Osamu Kitakami, Kentaro Toyoki, David Billington, Yoshinori Kotani, Tetsuya Nakamura, Taisuke Sasaki, Tadakatsu Ohkubo, Kazuhiro Hono, Yukio Takada, Takashi Sato, Yuji Kaneko, Akira Kato

    Acta Materialia 178 90-98 2019年10月

    出版者・発行元:Elsevier {BV}

    DOI: 10.1016/j.actamat.2019.08.004  

    ISSN:1359-6454

  45. Role of Ga on the high coercivity of Nd-rich Ga-doped Nd-Fe-B sintered magnet 査読有り

    Sasaki T. T, Takada Y, Okazaki H, Ohkubo T, Nakamura T, Sato T, Kato A, Kaneko Y, Hono K

    JOURNAL OF ALLOYS AND COMPOUNDS 790 750-759 2019年6月25日

    DOI: 10.1016/j.jallcom.2019.03.114  

    ISSN:0925-8388

  46. Change in chemical bonding state by thermal treatment in MgO-based magnetic tunnel junction observed by angle-resolved hard X-ray photoelectron spectroscopy 査読有り

    Masaaki Niwa, Akira Yasui, Eiji Ikenaga, Hiroaki Honjo, Shoji Ikeda, Tetsuya Nakamura, Tetsuo Endoh

    Journal of Applied Physics 125 (203903) 2019年5月28日

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.5094067  

    ISSN:0021-8979

    eISSN:1089-7550

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    This paper reports the relationship between the heat treatments of the CoFeB/MgO/CoFeB/Ta-based magnetic tunnel junction (MTJ) and the chemical bonding state using angle-resolved hard X-ray photoelectron spectroscopy. The redox reaction for B 1s during postannealing was verified for the MTJ without a capping layer by oxidizing the metallic B 1s in CoFeB and reducing the oxidized Fe 2p and Co 2p near the surface. For the MTJ with a capping layer, regardless of the heat treatments, MgO was found to be in a peroxidized state, and the diffusion of O 1s and B 1s exerted by the heat treatments is considered to be controlled by the degree of crystallization of MgO. The composition at the MgO/CoFeB interface changes on account of the heat treatments since the ratio of CoFeB and TaB at the bottom changes as a result of boron diffusion through the grain boundaries in MgO. By postannealing at 400 degrees C, the peak binding energy of Mg 1s at the surface was found to shift slightly to lower energy toward the stoichiometric MgO. However, the release of the excess oxygen in MgO is suppressed by the crystallization. Since the crystallization of MgO is enhanced by the in situ IR heating, the internal oxygen is more constrained in MgO. An improvement of the tunneling magnetoresistance deterioration observed with an ultrathin MgO is considered to be achieved under the peroxidized state controlled by the crystallinity of MgO. Published under license by AIP Publishing.

  47. Microscopic origin of large perpendicular magnetic anisotropy in an FeIr/MgO system 査読有り

    Shinji Miwa, Takayuki Nozaki, Masahito Tsujikawa, Motohiro Suzuki, Takuya Tsukahara, Takeshi Kawabe, Yoshinori Kotani, Kentaro Toyoki, Minori Goto, Tetsuya Nakamura, Masafumi Shirai, Shinji Yuasa, Yoshishige Suzuki

    Physical Review B 99 (18) 2019年5月16日

    出版者・発行元:American Physical Society (APS)

    DOI: 10.1103/physrevb.99.184421  

    ISSN:2469-9950

    eISSN:2469-9969

  48. Observation of orbital angular momentum in the chiral magnet CrNb3S6 査読有り

    M. Mito, H. Ohsumi, T. Shishidou, F. Kuroda, M. Weinert, K. Tsuruta, Y. Kotani, T. Nakamura, Y. Togawa, J. Kishine, Y. Kousaka, J. Akimitsu, K. Inoue

    Physical Review B 99 (17) 174439 2019年5月

    出版者・発行元:None

    DOI: 10.1103/PhysRevB.99.174439  

    ISSN:2469-9950

    eISSN:2469-9969

  49. Enhanced spin–orbit torque via interface engineering in Pt/CoFeB/MgO heterostructures 査読有り

    Hae-Yeon Lee, Sanghoon Kim, June-Young Park, Young-Wan Oh, Seung-Young Park, Wooseung Ham, Yoshinori Kotani, Tetsuya Nakamura, Motohiro Suzuki, Teruo Ono, Kyung-Jin Lee, Byong-Guk Park

    APL Materials 7 (3) 031110-031110 2019年3月

    出版者・発行元:{AIP} Publishing

    DOI: 10.1063/1.5084201  

    eISSN:2166-532X

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    Spin-orbit torque facilitates efficient magnetization switching via an<br /> in-plane current in perpendicularly magnetized heavy metal/ferromagnet<br /> heterostructures. The efficiency of spin-orbit-torque-induced switching is<br /> determined by the charge-to-spin conversion arising from either bulk or<br /> interfacial spin-orbit interactions, or both. Here, we demonstrate that the<br /> spin-orbit torque and the resultant switching efficiency in Pt/CoFeB systems<br /> are significantly enhanced by an interfacial modification involving Ti<br /> insertion between the Pt and CoFeB layers. Spin pumping and X-ray magnetic<br /> circular dichroism experiments reveal that this enhancement is due to an<br /> additional interface-generated spin current of the nonmagnetic interface and/or<br /> improved spin transparency achieved by suppressing the proximity-induced moment<br /> in the Pt layer. Our results demonstrate that interface engineering affords an<br /> effective approach to improve spin-orbit torque and thereby magnetization<br /> switching efficiency.

  50. Impact of carbon segregant on microstructure and magnetic properties of FePt-C nanogranular films on MgO (001) substrate 査読有り

    J. Wang, H. Sepehri-Amin, H. Tajiri, T. Nakamura, K. Masuda, Y.K. Takahashi, T. Ina, T. Uruga, I. Suzuki, Y. Miura, K. Hono

    Acta Materialia 166 413-423 2019年3月

    出版者・発行元:Elsevier {BV}

    DOI: 10.1016/j.actamat.2019.01.001  

    ISSN:1359-6454

  51. Perpendicular magnetic anisotropy and its electric-field-induced change at metal-dielectric interfaces 査読有り

    Shinji Miwa, Motohiro Suzuki, Masahito Tsujikawa, Takayuki Nozaki, Tetsuya Nakamura, Masafumi Shirai, Shinji Yuasa, Yoshishige Suzuki

    Journal of Physics D: Applied Physics 52 (6) 2019年2月6日

    出版者・発行元:{IOP} Publishing

    DOI: 10.1088/1361-6463/aaef18  

    ISSN:0022-3727

    eISSN:1361-6463

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    Electric-field-induced control of magnetic properties at room temperature has attracted considerable attention owing to its significant potential for facilitating the construction of ultralow-power-consumption electric devices. Voltage-controlled magnetic anisotropy (VCMA) effect in ultrathin ferromagnetic metals has shown that the magnetization of nanomagnets can be controlled by electric fields in extremely short periods (down to 0.1 ns). The VCMA effect in metals can be the ultimate technology for the operation of spintronics devices, such as nonvolatile random access memory, where high-speed operation with high writing endurance is indispensable. This review summarizes experimental studies of the VCMA effect. First, studies on VCMA in various systems are reviewed. Then, useful experimental and theoretical methods for VCMA research, i.e. electrical measurements using magnetic tunnel junction devices, x-ray magnetic circular dichroism spectroscopy, and first-principles studies, are described. Finally, the oxygen ion migration mechanism for electrochemical VCMA and the orbital magnetic moment and electric quadrupole mechanisms for purely electronic VCMA are discussed in detail.

  52. Electron-Transfer Activity in a Cyanide-Bridged Fe-42 Nanomagnet 査読有り

    Baker, Michael L., Wu, Shu-Qi, Kang, Soonchul, Matsuzawa, Satoshi, Arrio, Marie-Anne, Narumi, Yasuo, Kihara, Takumi, Nakamura, Tetsuya, Kotani, Yoshinori, Sato, Osamu, Nojiri, Hiroyuki

    Inorganic Chemistry 58 10160-10166 2019年

    DOI: 10.1021/ACS.INORGCHEM.9B01216  

  53. Detection of Spin Transfer from Metal to Molecule by Magnetoresistance Measurement 国際誌 査読有り

    Hiromu Gamou, Koki Shimose, Ryoto Enoki, Emi Minamitani, Akitoshi Shiotari, Yoshinori Kotani, Kentaro Toyoki, Tetsuya Nakamura, Yoshiaki Sugimoto, Makoto Kohda, Junsaku Nitta, Shinji Miwa

    Nano Letters 20 (1) 75-80 2019年

    DOI: 10.1021/acs.nanolett.9b03110  

    ISSN:1530-6984

    eISSN:1530-6992

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    © 2019 American Chemical Society. Localized electronic spin state in molecules has a relatively long spin lifetime and has thus attracted much attention. In this study, we characterize the magnetoresistance of a system comprising Pt and Fe(II)-phthalocyanine (FePc) molecules. The magnetoresistance measurement with the weak antilocalization analysis reveals that a magnetic moment in FePc acts as magnetic impurities for conduction electrons in Pt. Moreover, we find that the magnetoresistance involves a component that possesses the same symmetry as spin-Hall magnetoresistance. These results reveal the spin-angular momentum transfer from metallic Pt to a magnetic moment in FePc molecules, which can be used as a spin torque in a molecular system.

  54. First-order reversal curve analysis of a Nd-Fe-B sintered magnet with soft X-ray magnetic circular dichroism microscopy 査読有り

    Kazunori Miyazawa, Satoshi Okamoto, Takahiro Yomogita, Nobuaki Kikuchi, Osamu Kitakami, Kentaro Toyoki, David Billington, Yoshinori Kotani, Tetsuya Nakamura, Taisuke Sasaki, Tadakatsu Ohkubo, Kazuhiro Hono

    Acta Materialia 162 1-9 2019年1月

    出版者・発行元:Elsevier {BV}

    DOI: 10.1016/j.actamat.2018.09.053  

    ISSN:1359-6454

  55. Observation of the magnetoelectric reversal process of the antiferromagnetic domain 査読有り

    Yu Shiratsuchi, Shunsuke Watanabe, Hiroaki Yoshida, Noriaki Kishida, Ryoichi Nakatani, Yoshinori Kotani, Kentaro Toyoki, Tetsuya Nakamura

    Applied Physics Letters 113 (24) 2018年12月10日

    DOI: 10.1063/1.5053925  

    ISSN:0003-6951

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    © 2018 Author(s). We investigated the switching process of the perpendicular exchange bias, which is driven by the magnetoelectric effect, by conducting magnetic domain observations using scanning soft X-ray magnetic circular dichroism microscopy. Isothermal and simultaneous application of magnetic and electric fields switches the perpendicular exchange bias polarity. The switching process proceeds by the nucleation and growth of reversed domains. The correspondence among the ferromagnetic/antiferromagnetic domains and exchange bias polarity indicates that interfacial antiferromagnetic spin/domain reversal is responsible for the magnetoelectric switching of the perpendicular exchange bias polarity.

  56. Manipulation of Antiferromagnetic Spin Using Tunable Parasitic Magnetization in Magnetoelectric Antiferromagnet 査読有り

    Tomohiro Nozaki, Muftah Al‐Mahdawi, Yohei Shiokawa, Satya Prakash Pati, Shujun Ye, Yoshinori Kotani, Kentaro Toyoki, Tetsuya Nakamura, Motohiro Suzuki, Syougo Yonemura, Tatsuo Shibata, Masashi Sahashi

    physica status solidi (RRL) – Rapid Research Letters 12 (12) 1800366-1800366 2018年12月

    出版者・発行元:Wiley

    DOI: 10.1002/pssr.201800366  

    ISSN:1862-6254

    eISSN:1862-6270

  57. Antiferromagnetic domain wall creep driven by magnetoelectric effect 査読有り

    Yu Shiratsuchi, Hiroaki Yoshida, Yoshinori Kotani, Kentaro Toyoki, Thi Van Anh Nguyen, Tetsuya Nakamura, Ryoichi Nakatani

    APL Materials 6 (12) 2018年12月

    DOI: 10.1063/1.5053928  

    eISSN:2166-532X

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    © 2018 Author(s). We observed the magnetoelectric induced domain wall propagation in a Pt/Co/Au/Cr 2 O 3 /Pt stacked thin film based on magnetic domain observations using scanning soft X-ray magnetic circular dichroism microscopy. The antiferromagnetic (Cr 2 O 3 ) domain wall velocity was estimated by a quasi-static approach using a pulsed voltage. At a pulse voltage amplitude of -12 V, corresponding to an electric field of -8.0 × 10 2 kV/cm, the domain wall velocity was very low, at 0.3 m/s. The domain wall velocity increased with increasing voltage amplitude, reaching 22 m/s at -20 V (-1.3 × 10 3 kV/cm). The change in the domain wall velocity with the applied voltage amplitude indicates the creep motion of the domain wall. Using a phenomenological model, we estimated the domain wall depinning energy, and found that the bulk and interface terms of the magnetic anisotropy affect the effective magnetic field to the same degree, suggesting that the magnetic domain wall motion may be controllable by the antiferromagnetic layer thickness.

  58. Electric field effect on magnetism in a MgO/Pd/Co system with a solid-state capacitor structure 査読有り

    Aya Obinata, Takamasa Hirai, Yoshinori Kotani, Kentaro Toyoki, Tetsuya Nakamura, Tomohiro Koyama, Daichi Chiba

    AIP Advances 8 (11) 2018年11月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.5039680  

    ISSN:2158-3226

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    The electric field effect on the magnetism in a MgO/Pd/Co system, in which a magnetic moment is induced in the Pd layer owing to the ferromagnetic proximity effect, has been investigated using various experimental methods. An electric field was applied to the surface of the Pd layer through a solid-state HfO2/MgO dielectric bilayer by applying a gate voltage with a back-gating configuration. Changes in the magnetic properties of the system as a result of gate voltage application were detected using magnetization and polar-Kerr effect measurements as well as X-ray absorption and X-ray magnetic circular dichroism (XMCD) spectroscopies. A systematic change in the magnetic moment of the system by the application of a gate voltage is observed. The magnetic hysteresis loops obtained by the polar-Kerr effect measurement and the element-specific XMCD signal at the Co L-3-edge clearly show a reproducible change in the coercivity that is dependent on the gate voltage. (c) 2018 Author(s).

  59. Temperature dependence of the crystal structures and phase fractions of secondary phases in a Nd-Fe-B sintered magnet 査読有り

    Tsuji, N., Okazaki, H., Ueno, W., Kotani, Y., Billington, D., Yasui, A., Kawaguchi, S., Sugimoto, K., Toyoki, K., Fukagawa, T., Nishiuchi, T., Gohda, Y., Hirosawa, S., Hono, K., Nakamura, T.

    Acta Materialia 154 25-32 2018年

    出版者・発行元:Elsevier BV

    DOI: 10.1016/j.actamat.2018.05.020  

    ISSN:1359-6454

  60. Inserted metals for low-energy magnetoelectric switching in a Cr<inf>2</inf>O<inf>3</inf>/ferromagnet interfacial exchange-biased thin film system 査読有り

    Ye, S., Nozaki, T., Kotani, Y., Toyoki, K., Nakamura, T., Yonemura, S., Shibata, T., Pati, S.P., Al-Mahdawi, M., Shiokawa, Y., Sahashi, M.

    Journal of Materials Chemistry C 6 (12) 2962-2969 2018年

    出版者・発行元:Royal Society of Chemistry (RSC)

    DOI: 10.1039/c7tc05375d  

    ISSN:2050-7526

    eISSN:2050-7534

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    <p>Inserted metals work as a part of a stacked ferromagnetic film for low-energy magnetoelectric switching in a Cr<sub>2</sub>O<sub>3</sub>–antiferromagnet/ferromagnet interfacial exchange-biased system.</p>

  61. Geometrical protection of topological magnetic solitons in microprocessed chiral magnets 査読有り

    Mito, M., Ohsumi, H., Tsuruta, K., Kotani, Y., Nakamura, T., Togawa, Y., Shinozaki, M., Kato, Y., Kishine, J.-I., Ohe, J.-I., Kousaka, Y., Akimitsu, J., Inoue, K.

    Physical Review B 97 (2) 2018年

    出版者・発行元:American Physical Society

    DOI: 10.1103/PhysRevB.97.024408  

    ISSN:2469-9969 2469-9950

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    A chiral soliton lattice stabilized in a monoaxial chiral magnet CrNb3S6 is a magnetic superlattice consisting of magnetic kinks with a ferromagnetic background. The magnetic kinks are considered to be topological magnetic solitons (TMSs). Changes in the TMS number yield discretized responses in magnetization and electrical conductivity, and this effect is more prominent in smaller crystals. We demonstrate that, in microprocessed CrNb3S6 crystals, TMSs are geometrically protected through element-selected micromagnetometry using soft x-ray magnetic circular dichroism (MCD). A series of x-ray MCD data is supported by mean-field and micromagnetic analyses. By designing the microcrystal geometry, TMS numbers can be successfully changed and fixed over a wide range of magnetic fields.

  62. Correlation of the Dzyaloshinskii-Moriya interaction with Heisenberg exchange and orbital asphericity 国際誌 査読有り

    Kim, S., Ueda, K., Go, G., Jang, P.-H., Lee, K.-J., Belabbes, A., Manchon, A., Suzuki, M., Kotani, Y., Nakamura, T., Nakamura, K., Koyama, T., Chiba, D., Yamada, K.T., Kim, D.-H., Moriyama, T., Kim, K.-J., Ono, T.

    Nature Communications 9 (1) 1648-1648 2018年

    DOI: 10.1038/s41467-018-04017-x  

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    Chiral spin textures of a ferromagnetic layer in contact to a heavy non-magnetic metal, such as Néel-type domain walls and skyrmions, have been studied intensively because of their potential for future nanomagnetic devices. The Dyzaloshinskii-Moriya interaction (DMI) is an essential phenomenon for the formation of such chiral spin textures. In spite of recent theoretical progress aiming at understanding the microscopic origin of the DMI, an experimental investigation unravelling the physics at stake is still required. Here we experimentally demonstrate the close correlation of the DMI with the anisotropy of the orbital magnetic moment and with the magnetic dipole moment of the ferromagnetic metal in addition to Heisenberg exchange. The density functional theory and the tight-binding model calculations reveal that inversion symmetry breaking with spin-orbit coupling gives rise to the orbital-related correlation. Our study provides the experimental connection between the orbital physics and the spin-orbit-related phenomena, such as DMI.

  63. Angular dependence of coercivity in isotropically aligned Nd-Fe-B sintered magnets 査読有り

    Matsuura, Y., Nakamura, T., Sumitani, K., Kajiwara, K., Tamura, R., Osamura, K.

    AIP Advances 8 (5) 2018年

    出版者・発行元:American Institute of Physics Inc.

    DOI: 10.1063/1.5005040  

    ISSN:2158-3226

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    In order to understand the coercivity mechanism in Nd-Fe-B sintered magnets, the angular dependence of the coercivity of an isotropically aligned Nd15Co1.0B6Febal. sintered magnet was investigated through magnetization measurements using a vibrating sample magnetometer. These results are compared with the angular dependence calculated under the assumption that the magnetization reversal of each grain follows the Kondorskii law or, in other words, the 1/cos θ law for isotropic alignment distributions. The calculated angular dependence of the coercivity agrees very well with the experiment for magnetic fields applied between angles of 0 and 60°, and it is expected that the magnetization reversal occurs in each grain individually followed the 1/cos θ law. In contrast, this agreement between calculation and experiment is not found for anisotropic Nd-Fe-B samples. This implies that the coercivity of the aligned magnets depends upon the de-pinning of the domain walls from pinning sites. When the de-pinning occurs, it is expected that the domain walls are displaced through several grains at once.

  64. Angular dependence of coercivity derived from alignment dependence of coercivity in Nd-Fe-B sintered magnets 査読有り

    Matsuura, Y., Nakamura, T., Sumitani, K., Kajiwara, K., Tamura, R., Osamura, K.

    AIP Advances 8 (1) 015226-015226 2018年

    出版者・発行元:{AIP} Publishing

    DOI: 10.1063/1.4985740  

    ISSN:2158-3226

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    Experimental results of the alignment dependence of the coercivity in Nd-Fe-B sintered magnets showed that the angle of magnetization reversal for anisotropically aligned magnets was bigger than that obtained from the theoretical results calculated using the postulation that every grain independently reverses its magnetization direction following the 1/cos θ law. The angles of reversed magnetization (θ1) for Nd13.48Co0.55B5.76Febal. with alignment α=0.95 and for Nd12.75Dy0.84B5.81Co0.55Febal. with α=0.96 were 30° and 36°, respectively, which were very similar to that of an ideal magnet with a Gaussian distribution (σ=31° and 44°, respectively) of the grain alignment. In this model, we postulated that every grain independently reversed according to the 1/cos θ law. The calculation results for the angular dependence of the coercivity using the values θ1=ω1(0°)=30°, σ=31° and θ1=ω1(0°)=36°, σ=44° could qualitatively and convincingly explain the observed angular dependence of the coercivity of Nd14.2B6.2Co1.0Febal. and Nd14.2Dy0.3B6.2Co1.0Febal.. It is speculated that the magnetic domain wall is pinned at grains tilted away from the easy magnetization direction, and when the magnetic domain wall de-pins from the tilted grains, the magnetic domain wall jumps through several grains. We suggest that the coercive force of the aligned magnet behaves like a low-aligned magnet owing to the magnetization reversal of the crust of the grains induced by the pinning and subsequent jumping of the magnetic domain wall.

  65. Characterization of the magnetic moments of ultrathin Fe film in an external electric field via high-precision X-ray magnetic circular dichroism spectroscopy 査読有り

    Takuya Tsukahara, Takeshi Kawabe, Koki Shimose, Taishi Furuta, Risa Miyakaze, Kohei Nawaoka, Minori Goto, Takayuki Nozaki, Shinji Yuasa, Yoshinori Kotani, Kentaro Toyoki, Motohiro Suzuki, Tetsuya Nakamura, Yoshishige Suzuki, Shinji Miwa

    Japanese Journal of Applied Physics 56 (6) 060304-060304 2017年5月

    出版者・発行元:Japan Society of Applied Physics

    DOI: 10.7567/jjap.56.060304  

    ISSN:0021-4922

    eISSN:1347-4065

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    The magnetic moments of a Pt broken vertical bar Fe(0.5 nm)broken vertical bar MgO film at an external electric field of in a 0.35V/nm were characterized by analyzing the X-ray magnetic circular dichroism (XMCD) at the L-edges of Fe using a partial fluorescence yield method with a precision 40 times greater than that in our previous study. The XMCD induced by the electric field was negligible (&lt; 0.2%). Furthermore, although an induced orbital magnetic moment seemingly existed, it was within the precision error (0.3%). This paper demonstrates that slight electron doping and/or redistribution without any electrochemical reaction causes voltage-controlled magnetic anisotropy at Fe broken vertical bar MgO interfaces. (C) 2017 The Japan Society of Applied Physics

  66. 40 T Soft X-ray Spectroscopies on Magnetic-Field-Induced Valence Transition in Eu(Rh1−xIrx)2Si2 (x = 0.3) 査読有り

    Hiromasa Yasumura, Yasuo Narumi, Tetsuya Nakamura, Yoshinori Kotani, Akira Yasui, Eigo Kishaba, Akihiro Mitsuda, Hirofumi Wada, Koichi Kindo, Hiroyuki Nojiri

    Journal of the Physical Society of Japan 86 (5) 054706-054706 2017年5月

    出版者・発行元:Physical Society of Japan

    DOI: 10.7566/jpsj.86.054706  

    ISSN:0031-9015

  67. Voltage controlled interfacial magnetism through platinum orbits 査読有り

    Miwa, S., Suzuki, M., Tsujikawa, M., Matsuda, K., Nozaki, T., Tanaka, K., Tsukahara, T., Nawaoka, K., Goto, M., Kotani, Y., Ohkubo, T., Bonell, F., Tamura, E., Hono, K., Nakamura, T., Shirai, M., Yuasa, S., Suzuki, Y.

    Nature Communications 8 15848 EP 2017年

    出版者・発行元:NATURE PUBLISHING GROUP

    DOI: 10.1038/ncomms15848  

    ISSN:2041-1723

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    Electric fields at interfaces exhibit useful phenomena, such as switching functions in transistors, through electron accumulations and/or electric dipole inductions. We find one potentially unique situation in a metal-dielectric interface in which the electric field is atomically inhomogeneous because of the strong electrostatic screening effect in metals. Such electric fields enable us to access electric quadrupoles of the electron shell. Here we show, by synchrotron X-ray absorption spectroscopy, electric field induction of magnetic dipole moments in a platinum monatomic layer placed on ferromagnetic iron. Our theoretical analysis indicates that electric quadrupole induction produces magnetic dipole moments and provides a large magnetic anisotropy change. In contrast with the inability of current designs to offer ultrahigh-density memory devices using electric-field-induced spin control, our findings enable a material design showing more than ten times larger anisotropy energy change for such a use and highlight a path in electric-field control of condensed matter.

  68. Simultaneous achievement of high perpendicular exchange bias and low coercivity by controlling ferromagnetic/antiferromagnetic interfacial magnetic anisotropy 査読有り

    Shiratsuchi,Yu, Kuroda,Wataru, Nguyen,Thi Van Anh, Kotani,Yoshinori, Toyoki,Kentaro, Nakamura,Tetsuya, Suzuki,Motohiro, Nakamura,Kohji, Nakatani,Ryoichi

    Journal of Applied Physics 121 (7) 073902-073902 2017年

    出版者・発行元:{AIP} Publishing

    DOI: 10.1063/1.4976568  

    ISSN:0021-8979

    eISSN:1089-7550

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    This study investigates the influence of Pt and Au spacer layers on the perpendicular exchange bias field and coercivity of Pt/Co/(Pt or Au)/Cr2O3/Pt films. When using a Pt-spacer, the perpendicular exchange bias was highly degraded to less than 0.1 erg/cm(2), which was about half that of the Auspacer system. The Au spacer also suppressed the enhancement in coercivity that usually occurs at around room temperature when using Pt. It is suggested that this difference in exchange bias field is due to in-plane interfacial magnetic anisotropy at the Pt/Cr2O3 interface, which cants the interfacial Cr spin from the surface normal and results in degradation in the perpendicular exchange

  69. Optical control of magnetization dynamics in Gd-Fe-Co films with different compositions 査読有り

    Ohkochi, T., Fujiwara, H., Kotsugi, M., Takahashi, H., Adam, R., Sekiyama, A., Nakamura, T., Tsukamoto, A., Schneider, C.M., Kuroda, H., Arguelles, E.F., Sakaue, M., Kasai, H., Tsunoda, M., Suga, S., Kinoshita, T.

    Applied Physics Express 10 (10) 2017年

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.7567/APEX.10.103002  

    ISSN:1882-0778

    eISSN:1882-0786

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    Perpendicularly magnetized ferrimagnetic Gd-Fe-Co thin films with different corrposifions and multilayer arrangements were subjected to femtosecond laser pulses. The!pulses triggered different magnetization dynamics in the various thin films. In the Gd26Fe66Co8 film, which has an angular-momenturn-compensafion temperature (TA) well above ambient temperature (Tstp), monotonic magnetizafion reversal occurred, whereas the Gd22Fe70Co8 film (where TA is well below T-exp) exhibited remarkable wavelike spin modulafion with spafial inhomogeneity during relaxation of the laser-induced nonequilibrium Mate. These findings can enable broad-range tuning of the magneto-optical responses of Gd-Fe-Co alloys, facilitating advances in materials engineering. (C) 2017 The Japan Societyi of Applied Physics

  70. Electric-field-induced changes of magnetic moments and magnetocrystalline anisotropy in ultrathin cobalt films 査読有り

    Kawabe, T., Yoshikawa, K., Tsujikawa, M., Tsukahara, T., Nawaoka, K., Kotani, Y., Toyoki, K., Goto, M., Suzuki, M., Nakamura, T., Shirai, M., Suzuki, Y., Miwa, S.

    Physical Review B 96 (22) 2017年

    出版者・発行元:American Physical Society (APS)

    DOI: 10.1103/PhysRevB.96.220412  

    ISSN:2469-9950

    eISSN:2469-9969

  71. Contributions of Co and Fe orbitals to perpendicular magnetic anisotropy of MgO/CoFeB bilayers with Ta, W, IrMn, and Ti underlayers 査読有り

    Kim, S., Baek, S.C., Ishibashi, M., Yamada, K., Taniguchi, T., Okuno, T., Kotani, Y., Nakamura, T., Kim, K.-J., Moriyama, T., Park, B.-G., Ono, T.

    Applied Physics Express 10 (7) 2017年

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.7567/APEX.10.073006  

    ISSN:1882-0778

    eISSN:1882-0786

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    We study the perpendicular magnetic anisotropy (PMA) of the CoFeB/MgO bilayers in contact with W, Ta, IrMn, and Ti, which have been suggested for use as the spin-orbit-torque-related underlayers. The saturation magnetization of CoFeB depends on the underlayer material used owing to the formation of a dead layer that affects the PMA strength of each film. The X-ray magnetic circular dichroism measurement reveals that interfacial intermixing suppresses only the perpendicular orbital moment of Fe, whereas it simultaneously suppresses both the perpendicular and in-plane orbital moments of Co. (C) 2017 The Japan Society of Applied Physics

  72. Completely compensated ferrimagnetism and sublattice spin crossing in the half-metallic Heusler compound Mn1.5 FeV0.5 Al 査読有り

    Stinshoff, R., Nayak, A.K., Fecher, G.H., Balke, B., Ouardi, S., Skourski, Y., Nakamura, T., Felser, C.

    Physical Review B 95 (6) 2017年

    出版者・発行元:AMER PHYSICAL SOC

    DOI: 10.1103/PhysRevB.95.060410  

    ISSN:2469-9950

    eISSN:2469-9969

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    The Slater-Pauling rule states that L2(1) Heusler compounds with 24 valence electrons never exhibit a total spin magnetic moment. In the case of strongly localized magnetic moments at one of the atoms (here Mn) they will exhibit a fully compensated half-metallic ferrimagnetic state instead, in particular, when symmetry does not allow for antiferromagnetic order. With the aid of magnetic and anomalous Hall effect measurements, it is experimentally demonstrated that Mn1.5V0.5FeAl follows such a scenario. The ferrimagnetic state is tuned by the composition. A small residual magnetization, which arises due to a slight mismatch of the magnetic moments in the different sublattices, results in a pronounced change of the temperature dependence of the ferrimagnet. A compensation point is confirmed by observation of magnetic reversal and sign change of the anomalous Hall effect. Theoretical models are presented that correlate the electronic structure and the compensation mechanisms of the different half-metallic ferrimagnetic states in the Mn-V-Fe-Al Heusler system.

  73. Characterization of the magnetic moments of ultrathin Fe film in an external electric field via high-precision X-ray magnetic circular dichroism spectroscopy 査読有り

    Tsukahara, T., Kawabe, T., Shimose, K., Furuta, T., Miyakaze, R., Nawaoka, K., Goto, M., Nozaki, T., Yuasa, S., Kotani, Y., Toyoki, K., Suzuki, M., Nakamura, T., Suzuki, Y., Miwa, S.

    Japanese Journal of Applied Physics 56 (6) 2017年

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.7567/JJAP.56.060304  

    ISSN:0021-4922

    eISSN:1347-4065

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    The magnetic moments of a Pt broken vertical bar Fe(0.5 nm)broken vertical bar MgO film at an external electric field of in a 0.35V/nm were characterized by analyzing the X-ray magnetic circular dichroism (XMCD) at the L-edges of Fe using a partial fluorescence yield method with a precision 40 times greater than that in our previous study. The XMCD induced by the electric field was negligible (&lt; 0.2%). Furthermore, although an induced orbital magnetic moment seemingly existed, it was within the precision error (0.3%). This paper demonstrates that slight electron doping and/or redistribution without any electrochemical reaction causes voltage-controlled magnetic anisotropy at Fe broken vertical bar MgO interfaces. (C) 2017 The Japan Society of Applied Physics

  74. Angle-Resolved HAXPES Investigation on the Chemical Origin of Adhesion between Natural Rubber and Brass 査読有り

    Ozawa, K., Kakubo, T., Amino, N., Mase, K., Ikenaga, E., Nakamura, T.

    Langmuir 33 (38) 9582-9589 2017年

    出版者・発行元:AMER CHEMICAL SOC

    DOI: 10.1021/acs.langmuir.7b01842  

    ISSN:0743-7463

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    Bulk sensitivity of hard X-ray photoelectron spectroscopy (HAXPES) makes this technique suitable for chemical state analysis of bulk and deeply buried interfaces of solid materials. HAXPES is employed in the present study to examine the chemical state of adhesive interfaces between natural rubber and copper zinc alloy, i.e., brass, while maintaining the adhesion structure in order to understand the chemical mechanism of rubber-to-brass adhesion. Angle resolved measurements allow to distinguish between chemical species in rubber and those at the adhesive interface. We specially focus on sulfur-containing species because metal sulfides at the interface have been suggested to be crucial for adhesion. Line-shape analysis of S is spectra reveals that the interface that exhibits a strong adhesive property is mainly composed of copper sulfides with a predominant amount of CuS. This type of the interfacial chemical state is obtained when a rubber-bonded brass sample is subjected to vulcanization at 170 degrees C for 10 min. However, prolonged vulcanization leads to a partial dissolution of CuS as well as accumulation of Zn species in the form of ZnO/Zn(OH)(2) and ZnS, and as a result, adhesion strength is lowered. The present study paves the way for accurate and detailed discussion on the chemical state of deeply buried interfaces through bulk sensitive in-situ measurements.

  75. 40t soft X-ray spectroscopies on magnetic-field-induced valence transition in Eu(Rh<inf>1-x</inf>Ir<inf>x</inf>)<inf>2</inf>Si<inf>2</inf>(x = 0.3) 査読有り

    Yasumura, H., Narumi, Y., Nakamura, T., Kotani, Y., Yasui, A., Kishaba, E., Mitsuda, A., Wada, H., Kindo, K., Nojiri, H.

    Journal of the Physical Society of Japan 86 (5) 2017年

    出版者・発行元:PHYSICAL SOC JAPAN

    DOI: 10.7566/JPSJ.86.054706  

    ISSN:0031-9015

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    A magnetic-field-induced valence transition of Eu(Rh1-xIrx)(2)Si-2 (x = 0.3) has been examined using soft X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD) measurements up to 39.3 T. At 9K, the Eu valence number takes a value of 2.65 (+/- 0.03) at 0 T and decreases abruptly to 2.33 (+/- 0.03) at the transition around 22 T. Above the transition field, the magnetization of the Eu2+ component saturates, although the Van Vleck paramagnetism of the Eu3+ linearly increases and reaches 0.65 mu(B)/Eu3+ at 39 T. The valence determined by XAS and the saturation value of the bulk magnetization are mutually consistent. It is found that the transition field determined by XMCD differs from that of the bulk magnetization. To interpret the discrepancy, we discuss the sample inhomogeneity and the effect of the surface state.

  76. Half-metallic compensated ferrimagnetism with a tunable compensation point over a wide temperature range in the Mn-Fe-V-Al Heusler system 査読有り

    Stinshoff, R., Fecher, G.H., Chadov, S., Nayak, A.K., Balke, B., Ouardi, S., Nakamura, T., Felser, C.

    AIP Advances 7 (10) 105009-105009 2017年

    出版者・発行元:{AIP} Publishing

    DOI: 10.1063/1.5000351  

    ISSN:2158-3226

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    The cubic Heusler compound Mn1.5FeV0.5Al with the L2(1) Heusler structure is the first fully compensated half-metallic ferrimagnet with 24 valence electrons. The ferrimagnetic state can be tuned by changing the composition such that the compensation point appears at finite temperatures ranging from 0 K up to 226 K, while retaining half-metallicity in the system. In this paper, the structural, magnetic and transport properties of the Mn-Fe-V-Al system are discussed. Magnetic reversal and a change of sign of the anomalous Hall effect were observed at the compensation point, which gives rise to a sublattice spin-crossing. These materials present new possibilities for potential spintronic devices because of their advantageous properties such as imperceptibility to external fields, lower power consumption and ultrafast switching in the THz region. (C) 2017 Author(s).

  77. Evidence of Charge Transfer and Orbital Magnetic Moment in Multiferroic CuFeO2 査読有り

    Yasuo Narumi, Tetsuya Nakamura, Hidekazu Ikeno, Noriki Terada, Takayuki Morioka, Kota Saito, Hideaki Kitazawa, Koichi Kindo, Hiroyuki Nojiri

    Journal of the Physical Society of Japan 85 (11) 114705-114705 2016年11月

    出版者・発行元:Physical Society of Japan

    DOI: 10.7566/jpsj.85.114705  

    ISSN:0031-9015

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    Soft X-ray absorption spectra (XAS) and magnetic circular dichroism (XMCD) of Fe and Cu L-2,L-3 edges have been measured on the triangular lattice antiferromagnet CuFeO2. By applying sum rule analysis to the XMCD of Fe, the ratio of the orbital to spin magnetic moments is determined to be -0.071. Because the nominal valence of Fe in CuFeO2 was Fe3+ (3d(5)), the orbital magnetic moment was considered to be zero in the past. However, the present research demonstrates that the orbital magnetic moment of Fe takes a finite value and it is possibly due to Fe4+ (3d(4)), which is considered to be responsible for the strong magnetic anisotropy and the ferroelectricity. We compare the experimental results with the results of ab initio multiplet calculations based on the configuration interaction theory and discuss the anomalous electronic structures of Fe and Cu ions in CuFeO2.

  78. Upgrade of Beamline BL25SU for Soft X-ray Imaging and Spectroscopy of Solid Using Nano- and Micro-focused Beams at SPring-8 査読有り

    Yasunori Senba, Haruhiko Ohashi, Yoshinori Kotani, Tetsuya Nakamura, Takayuki Muro, Takuo Ohkochi, Naruki Tsuji, Hikaru Kishimoto, Takanori Miura, Masayuki Tanaka, Masahiro Higashiyama, Sunao Takahashi, Yasuhide Ishizawa, Tomohiro Matsushita, Yukito Furukawa, Toru Ohata, Nobuteru Nariyama, Kunikazu Takeshita, Toyohiko Kinoshita, Akihiko Fujiwara, Masaki Takata, Shunji Goto

    PROCEEDINGS OF THE 12TH INTERNATIONAL CONFERENCE ON SYNCHROTRON RADIATION INSTRUMENTATION (SRI2015) 1741 2016年

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.4952867  

    ISSN:0094-243X

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    Substantial upgrades have been made to the beamline BL25SU at SPring-8 for soft X-ray imaging and spectroscopy of solid-state materials. The upgraded beamline consists of two branches: a micro-beam branch with high energy resolution, and a nano-beam branch with small angular divergence. The beamline has been available for use since October 2014, following a half year commissioning period. We present here the beamline performance parameters, including resolving power, photon flux, and focused beam size, which are consistent with designed specifications.

  79. Simultaneous magnetic and chemical imaging of Nd-Fe-B thin films by means of XMCD-PEEM technique 査読有り

    Goto R., Okamoto S., Ohkochi T., Kikuchi N., Kitakami O., Nakamura T.

    Journal of the Magnetics Society of Japan 40 (4) 87-90 2016年

    出版者・発行元:公益社団法人 日本磁気学会

    DOI: 10.3379/msjmag.1605R004  

    ISSN:1882-2924

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    The coercivity mechanism of Nd-Fe-B thin film samples with and without Nd deposition was investigated by simultaneous chemical and magnetic imaging by means of X-ray magnetic circular dichroism-photoemission electron microscopy. The two Nd-Fe-B thin film samples exhibited almost the same surface morphology and magnetic domain patterns, but their coercive fields were quite different, being 0.98 T for the sample with Nd deposition and 0.55 T for sample without Nd deposition. The chemical distribution of Nd revealed that Nd aggregates with the average size of 130 nm exist, and the density in the Nd-deposited sample is much higher than that in the not deposited one. A comparison of the magnetic and chemical contrast images implied that the Nd aggregates act as domain wall pinning sites, indicating that the large coercivity difference in the Nd-Fe-B thin films would be attributable to the different density of wall pinning sites.

  80. Mixed-valence state of Ce and its individual atomic moments in Ce<inf>2</inf>Fe<inf>14</inf>B studied by soft X-ray magnetic circular dichroism 査読有り

    Wang, J., Liang, L., Zhang, L.T., Yano, M., Terashima, K., Kada, H., Kato, S., Kadono, T., Imada, S., Nakamura, T., Hirano, S.

    Intermetallics 69 42-46 2016年

    出版者・発行元:ELSEVIER SCI LTD

    DOI: 10.1016/j.intermet.2015.10.009  

    ISSN:0966-9795

    eISSN:1879-0216

    詳細を見る 詳細を閉じる

    We performed soft X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD) measurements at Fe L-2,L-3-edges and Ce M-4,M-5-edges on Ce2Fe14B at 300 K. The valence and total atomic moment of Ce in Ce2Fe14B were determined to be similar to+3.12 and similar to 0.100 mu(B), respectively, which mainly stem from a large portion of the well-localized 4f(1) configurations. Besides, the individual orbital and spin moments of Ce in Ce2Fe14B as well as those of Fe were determined for the first time with consideration of the magnetic dipole term. (c) 2015 Elsevier Ltd. All rights reserved.

  81. Magnetic domain evolution in Nd-Fe-B:Cu sintered magnet visualized by scanning hard X-ray microprobe 査読有り

    Suzuki, M., Yasui, A., Kotani, Y., Tsuji, N., Nakamura, T., Hirosawa, S.

    Acta Materialia 106 155-161 2016年

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.actamat.2016.01.011  

    ISSN:1359-6454

    eISSN:1873-2453

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    The formation and development of the magnetic domain structures of an Nd2Fe14B sintered magnet doped with 0.1% Cu are studied during the demagnetization process. A scanning hard X-ray microprobe with X-ray magnetic circular dichroism at the Nd L-2 edge is applied to investigate the evolution of magnetic domains with the applied magnetic field on a fractured surface. Reversed magnetic domains are initially formed in the Nd-Fe-B main phase grains beside the Cu-abundant regions that superposes on an Nd-rich phase. This characteristic formation of initial domains is reproducibly observed throughout several demagnetization cycles after the magnetization becomes saturated, suggesting the presence of specific nucleation sites that trigger the magnetization reversal. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  82. Ion Irradiation-Induced Magnetic Transition of MnGa Alloy Films Studied by X-Ray Magnetic Circular Dichroism and Low-Temperature Hysteresis Loops 査読有り

    D. Oshima, M. Tanimoto, T. Kato, Y. Fujiwara, T. Nakamura, Y. Kotani, S. Tsunashima, S. Iwata

    IEEE Transactions on Magnetics 52 (7) 1-4 2016年

    出版者・発行元:IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/TMAG.2016.2527050  

    ISSN:0018-9464

    eISSN:1941-0069

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    The ion irradiation-induced magnetic transition of L1(0)-MnGa alloy films was studied in detail by measuring X-ray magnetic circular dichroism (XMCD) and the temperature dependence of their hysteresis loops. The XMCD of (001)-oriented MnGa films exhibited different spectral shapes depending on whether magnetization was parallel or perpendicular to the film plane; that is considered to be the origin of the large perpendicular magnetic anisotropy of the L1(0)-MnGa. The anisotropy of XMCD spectra was not influenced by the ion irradiation to the MnGa, while the intensity of the XMCD signal decreased with increasing ion dose. From the measurement of hysteresis loops at low temperature, the significant increase of coercivity H-c in the ion-irradiated MnGa was found by lowering the temperature, while only a slight increase of H-c was observed in the as-prepared MnGa. These results suggest that the ion-irradiated MnGa film has a composite structure of L1(0)-ordered MnGa nanocrystals separated by an A1-disordered MnGa matrix, and that increasing the ion dose results in an increase in the volume ratio of A1-MnGa to L1(0)-MnGa in the film.

  83. Evidence of charge transfer and orbital magnetic moment in multiferroic CuFeO<inf>2</inf> 査読有り

    Narumi, Y., Nakamura, T., Ikeno, H., Terada, N., Morioka, T., Saito, K., Kitazawa, H., Kindo, K., Nojiri, H.

    Journal of the Physical Society of Japan 85 (11) 2016年

    出版者・発行元:PHYSICAL SOC JAPAN

    DOI: 10.7566/JPSJ.85.114705  

    ISSN:0031-9015

    詳細を見る 詳細を閉じる

    Soft X-ray absorption spectra (XAS) and magnetic circular dichroism (XMCD) of Fe and Cu L-2,L-3 edges have been measured on the triangular lattice antiferromagnet CuFeO2. By applying sum rule analysis to the XMCD of Fe, the ratio of the orbital to spin magnetic moments is determined to be -0.071. Because the nominal valence of Fe in CuFeO2 was Fe3+ (3d(5)), the orbital magnetic moment was considered to be zero in the past. However, the present research demonstrates that the orbital magnetic moment of Fe takes a finite value and it is possibly due to Fe4+ (3d(4)), which is considered to be responsible for the strong magnetic anisotropy and the ferroelectricity. We compare the experimental results with the results of ab initio multiplet calculations based on the configuration interaction theory and discuss the anomalous electronic structures of Fe and Cu ions in CuFeO2.

  84. Magnetic Domain Wall Energy in Ni/Co Superlattice 査読有り

    Kentaro Toyoki, Yu Shiratsuchi, Tetsuya Nakamura, Chiharu Mitsumata, Shotaro Harimoto, Yuichiro Takechi, Takashi Nishimura, Hikaru Nomura, Ryoichi Nakatani

    Applied Physics Lettters 106 162404 2015年4月

  85. Magnetic dichroism study on Mn1.8Co1.2Ga thin film using a combination of x-ray absorption and photoemission spectroscopy 査読有り

    Siham Ouardi, Gerhard H. Fecher, Takahide Kubota, Shigemi Mizukami, Eiji Ikenaga, Tetsuya Nakamura, Claudia Felser

    JOURNAL OF PHYSICS D-APPLIED PHYSICS 48 (16) 164007 2015年4月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0022-3727/48/16/164007  

    ISSN:0022-3727

    eISSN:1361-6463

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    Using circularly polarised radiation and a combination of bulk-sensitive hard x-ray photoelectron spectroscopy and x-ray-absorption spectroscopy (XAS) we studied the electronic and magnetic structure of epitaxial Mn1.8Co1.2Ga thin films. Spin-resolved Bloch spectral functions, density of states as well as charge and magnetisation densities were investigated by a first-principles analysis of full potential, fully relativistic Korringa-Kohn-Rostoker calculations of the electronic structure. The valence states were experimentally investigated by using linear dichroism in the angular distribution and comparing the results to spin-resolved densities of states. The linear dichroism in the valence band enabled a symmetry analysis of the contributing states. The spectra were in good agreement with the theoretical partial density of states. The element-specific, spin-resolved, unoccupied densities of states for Co and Mn were analysed by using XAS and x-ray magnetic circular dichroism (XMCD) at the L-3,L-2 edges. The spectra were influenced by strong correlation effects. XMCD was used to extract the site-resolved magnetic moments. The experimental values of m(Mn) = 0.7 mu(B) and m(Co) = 1.05 mu(B) agree very well with the calculated magnetic moments. Magnetic circular dichroism in angle-resolved photoelectron spectroscopy at the Mn and Co 2p core level exhibited a pronounced magnetic dichroism and confirmed the localised character of the Mn d valence states.

  86. Electric-Field-Induced Modification of the Magnon Energy, Exchange Interaction, and Curie Temperature of Transition-Metal Thin Films 査読有り

    M. Oba, K. Nakamura, T. Akiyama, T. Ito, M. Weinert, A. J. Freeman

    PHYSICAL REVIEW LETTERS 114 (10) 107202 2015年3月

    出版者・発行元:AMER PHYSICAL SOC

    DOI: 10.1103/PhysRevLett.114.107202  

    ISSN:0031-9007

    eISSN:1079-7114

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    The electric-field-induced modification in the Curie temperature of prototypical transition-metal thin films with the perpendicular magnetic easy axis, a freestanding Fe(001) monolayer and a Co monolayer on Pt(111), is investigated by first-principles calculations of spin-spiral structures in an external electric field (E field). An applied E field is found to modify the magnon (spin-spiral formation) energy; the change arises from the E-field-induced screening charge density in the spin-spiral states due to p-d hybridizations. The Heisenberg exchange parameters obtained from the magnon energy suggest an E-field-induced modification of the Curie temperature, which is demonstrated via Monte Carlo simulations that take the magnetocrystalline anisotropy into account.

  87. Porous coordination polymers with ubiquitous and biocompatible metals and a neutral bridging ligand 査読有り

    Shin-ichiro Noro, Junya Mizutani, Yuh Hijikata, Ryotaro Matsuda, Hiroshi Sato, Susumu Kitagawa, Kunihisa Sugimoto, Yasutaka Inubushi, Kazuya Kubo, Takayoshi Nakamura

    NATURE COMMUNICATIONS 6 2015年1月

    出版者・発行元:NATURE PUBLISHING GROUP

    DOI: 10.1038/ncomms6851  

    ISSN:2041-1723

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    The design of inexpensive and less toxic porous coordination polymers (PCPs) that show selective adsorption or high adsorption capacity is a critical issue in research on applicable porous materials. Although use of Group II magnesium(II) and calcium(II) ions as building blocks could provide cheaper materials and lead to enhanced biocompatibility, examples of magnesium(II) and calcium(II) PCPs are extremely limited compared with commonly used transition metal ones, because neutral bridging ligands have not been available for magnesium(II) and calcium(II) ions. Here we report a rationally designed neutral and charge-polarized bridging ligand as a new partner for magnesium(II) and calcium(II) ions. The three-dimensional magnesium(II) and calcium(II) PCPs synthesized using such a neutral ligand are stable and show selective adsorption and separation of carbon dioxide over methane at ambient temperature. This synthetic approach allows the structural diversification of Group II magnesium(II) and calcium(II) PCPs.

  88. Voltage-controlled magnetic anisotropy in Fe|MgO tunnel junctions studied by x-ray absorption spectroscopy 査読有り

    Miwa,Shinji, Matsuda,Kensho, Tanaka,Kazuhito, Kotani,Yoshinori, Goto,Minori, Nakamura,Tetsuya, Suzuki,Yoshishige

    Applied Physics Letters 107 (16) 162402-162402 2015年

    出版者・発行元:{AIP} Publishing

    DOI: 10.1063/1.4934568  

    ISSN:0003-6951

    eISSN:1077-3118

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    In this study, voltage-controlled magnetic anisotropy (VCMA) in Fe vertical bar MgO tunnel junctions was investigated via the magneto-optical Kerr effect, soft x-ray absorption spectroscopy, and magnetic circular dichroism spectroscopy. The Fe vertical bar MgO tunnel junctions showed enhanced perpendicular magnetic anisotropy under external negative voltage, which induced charge depletion at the Fe vertical bar MgO interface. Despite the application of voltages of opposite polarity, no trace of chemical reaction such as a redox reaction attributed to O2- migration was detected in the x-ray absorption spectra of the Fe. The VCMA reported in the Fe vertical bar MgO-based magnetic tunnel junctions must therefore originate from phenomena associated with the purely electric effect, that is, surface electron doping and/or redistribution induced by an external electric field. (C) 2015 AIP Publishing LLC.

  89. Valence-specific magnetization of the charge-ordered multiferroelectric LuFe2 O4 using soft x-ray magnetic circular dichroism under 30 T pulsed high magnetic fields 査読有り

    Narumi, Y., Nakamura, T., Saito, K., Morioka, T., Fukada, Y., Kambe, T., Ikeda, N., Kotani, Y., Kinoshita, T., Kindo, K., Nojiri, H.

    Physical Review B - Condensed Matter and Materials Physics 91 (1) 2015年

    出版者・発行元:AMER PHYSICAL SOC

    DOI: 10.1103/PhysRevB.91.014410  

    ISSN:2469-9950

    eISSN:2469-9969

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    Soft x-ray magnetic circular dichroism (XMCD) have been measured on the single crystal of the charge-ordered type multiferroelectric material LuFe2O4. By comparing the XMCD results with the bulk magnetizations, the valence-specific magnetizations (VSMs) of Fe2+ and Fe3+ ions are obtained. Both Fe2+ and Fe3+ ions show positive and negative remanent VSMs below the spin ordering temperature T-SO similar to 250 K, showing the ferrimagnetic long-range ordering directly. Both of the remanent VSMs disappear above the TSO and the field dependencies of the VSMs behave in paramagnetic fashions with convex and concave curvatures. However, the signs of the VSMs of Fe2+ and Fe3+ remain opposite, nevertheless the system is in a paramagnetic phase. This is direct evidence of the robust antiferromagnetic interaction between Fe2+ and Fe3+ ions even above the T-SO. As temperature increases, furthermore, the opposite VSM of Fe3+ is reversed around the three-dimensional charge ordering temperature T-CO similar to 330 K showing that both net magnetic moments of Fe2+ and Fe3+ become parallel to the applied magnetic field. Possible correlation between these unusual magnetic behaviors and the ferroelectric properties of LuFe2O4 is discussed.

  90. Ultrafast spin-switching of a ferrimagnetic alloy at room temperature traced by resonant magneto-optical Kerr effect using a seeded free electron laser 査読有り

    Yamamoto,Sh., Taguchi,M., Someya,T., Kubota,Y., Ito,S., Wadati,H., Fujisawa,M., Capotondi,F., Pedersoli,E., Manfredda,M., Raimondi,L., Kiskinova,M., Fujii,J., Moras,P., Tsuyama,T., Nakamura,T., Kato,T., Higashide,T., Iwata,S., Yamamoto,S., Shin,S., Matsuda,I.

    Review of Scientific Instruments 86 (8) 083901-083901 2015年

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.4927828  

    ISSN:0034-6748

    eISSN:1089-7623

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    Ultrafast magnetization reversal of a ferrimagnetic metallic alloy GdFeCo was investigated by time-resolved resonant magneto-optical Kerr effect measurements using a seeded free electron laser. The GdFeCo alloy was pumped by a linearly polarized optical laser pulse, and the following temporal evolution of the magnetization of Fe in GdFeCo was element-selectively traced by a probe free electron laser pulse with a photon energy tuned to the Fe M-edge. The results have been measured using rotating analyzer ellipsometry method and confirmed magnetization switching caused by ultrafast heating. (C) 2015 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.

  91. Tetragonal distortion and perpendicular magnetic anisotropy of FeCo layer in the FePt/FeCo and FePt/Cu/FeCo films. 査読有り

    B. Wang, H. Omiya, T. Hasegawa, T. Nakamura, L. Zhang, L. Liu, S. Ishio

    2015 IEEE MAGNETICS CONFERENCE (INTERMAG) 2015年

    出版者・発行元:IEEE

    DOI: 10.1109/INTMAG.2015.7157512  

  92. Temperature dependence of post-sintered annealing on magnetic properties of intergranular phase in Nd-Fe-B permanent magnet 査読有り

    Yasui, A., Nakamura, T., Kotani, Y., Fukagawa, T., Nishiuchi, T., Hirosawa, S.

    Journal of Applied Physics 117 (17) 2015年

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.4916938  

    ISSN:0021-8979

    eISSN:1089-7550

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    Post-sinter-annealing temperature (T-a) dependences of the chemical and magnetic properties of intergranular (grain boundary; GB) phase in a Nd14.0Fe79.7B6.2Cu0.1 sintered magnet have been investigated by x-ray absorption spectroscopy and its magnetic circular dichroism. A relative change of the Cu concentration in the GB phase is found to depend on T-a and shows the maximum at T-a - 500 degrees C. The T-a-dependence of the Cu concentration was very similar to that of the coercivity. On the other hand, there is no significant T-a-dependence for the magnetization at the fracture surface: the Fe magnetic moment is 1.7 +/- 0.036 mu(B) at all T-a. The Cu-rich layer segregated in the GB phase would have a key role in the coercivity enhancement of the Nd-Fe-B sintered magnet. (C) 2015 AIP Publishing LLC.

  93. Magnetic dichroism study on Mn&lt;inf&gt;1.8&lt;/inf&gt;Co&lt;inf&gt;1.2&lt;/inf&gt;Ga thin film using a combination of x-ray absorption and photoemission spectroscopy 査読有り

    Ouardi, S., Fecher, G.H., Kubota, T., Mizukami, S., Ikenaga, E., Nakamura, T., Felser, C.

    Journal of Physics D: Applied Physics 48 (16) 2015年

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0022-3727/48/16/164007  

    ISSN:0022-3727

    eISSN:1361-6463

    詳細を見る 詳細を閉じる

    Using circularly polarised radiation and a combination of bulk-sensitive hard x-ray photoelectron spectroscopy and x-ray-absorption spectroscopy (XAS) we studied the electronic and magnetic structure of epitaxial Mn1.8Co1.2Ga thin films. Spin-resolved Bloch spectral functions, density of states as well as charge and magnetisation densities were investigated by a first-principles analysis of full potential, fully relativistic Korringa-Kohn-Rostoker calculations of the electronic structure. The valence states were experimentally investigated by using linear dichroism in the angular distribution and comparing the results to spin-resolved densities of states. The linear dichroism in the valence band enabled a symmetry analysis of the contributing states. The spectra were in good agreement with the theoretical partial density of states. The element-specific, spin-resolved, unoccupied densities of states for Co and Mn were analysed by using XAS and x-ray magnetic circular dichroism (XMCD) at the L-3,L-2 edges. The spectra were influenced by strong correlation effects. XMCD was used to extract the site-resolved magnetic moments. The experimental values of m(Mn) = 0.7 mu(B) and m(Co) = 1.05 mu(B) agree very well with the calculated magnetic moments. Magnetic circular dichroism in angle-resolved photoelectron spectroscopy at the Mn and Co 2p core level exhibited a pronounced magnetic dichroism and confirmed the localised character of the Mn d valence states.

  94. Direct observations of ferromagnetic and antiferromagnetic domains in Pt/Co/Cr<sub>2</sub>O<sub>3</sub>/Pt perpendicular exchange biased film 査読有り

    Yu Shiratsuchi, Yoshinori Kotani, Saori Yoshida, Yasunori Yoshikawa, Kentaro Toyoki, Atsushi Kobane, Ryoichi Nakatani, Tetsuya Nakamura

    AIMS Materials Science 2 (4) 484-496 2015年

    出版者・発行元:American Institute of Mathematical Sciences (AIMS)

    DOI: 10.3934/matersci.2015.4.484  

    ISSN:2372-0484

  95. Anisotropic X-ray magnetic circular dichroism spectra of (001) oriented L1(0)-MnGa film 査読有り

    D. Oshima, M. Tanimoto, T. Kato, Y. Fujiwara, T. Nakamura, Y. Kotani, S. Tsunashima, S. Iwata

    2015 IEEE MAGNETICS CONFERENCE (INTERMAG) 2015年

    出版者・発行元:IEEE

    DOI: 10.1109/INTMAG.2015.7157522  

  96. A ferromagnetically coupled Fe 42 cyanide-bridged nanocage 査読有り

    Kang, S., Zheng, H., Liu, T., Hamachi, K., Kanegawa, S., Sugimoto, K., Shiota, Y., Hayami, S., Mito, M., Nakamura, T., Nakano, M., Baker, M.L., Nojiri, H., Yoshizawa, K., Duan, C., Sato, O.

    Nature Communications 6 2015年

    出版者・発行元:NATURE PUBLISHING GROUP

    DOI: 10.1038/ncomms6955  

    ISSN:2041-1723

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    Self-assembly of artificial nanoscale units into superstructures is a prevalent topic in science. In biomimicry, scientists attempt to develop artificial self-assembled nanoarchitectures. However, despite extensive efforts, the preparation of nanoarchitectures with superior physical properties remains a challenge. For example, one of the major topics in the field of molecular magnetism is the development of high-spin (HS) molecules. Here, we report a cyanide-bridged magnetic nanocage composed of 18 HS iron(III) ions and 24 low-spin iron(II) ions. The magnetic iron(III) centres are ferromagnetically coupled, yielding the highest ground-state spin number (S = 45) of any molecule reported to date.

  97. Signature of high T<inf>c</inf>above 25 K in high quality superconducting diamond 査読有り

    Okazaki, H., Wakita, T., Muro, T., Nakamura, T., Muraoka, Y., Yokoya, T., Kurihara, S.-I., Kawarada, H., Oguchi, T., Takano, Y.

    Applied Physics Letters 106 (5) 052601-052601 2015年

    出版者・発行元:{AIP} Publishing

    DOI: 10.1063/1.4907411  

    ISSN:0003-6951

    eISSN:1077-3118

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    We have observed zero resistivity above 10K and an onset of resistivity reduction at 25.2K in a heavily B-doped diamond film. However, the effective carrier concentration is similar to that of superconducting diamond with a lower T-c. We found that the carrier has a longer mean free path and lifetime than in the previous report, indicating that this highest T-c diamond has better crystallinity compared to that of other superconducting diamond films. In addition, the susceptibility shows a small transition above 20K in the high quality diamond, suggesting a signature of superconductivity above 20 K. These results strongly suggest that heavier carrier doped defect-free crystalline diamond could give rise to high T-c diamond. (C) 2015 AIP Publishing LLC.

  98. Magnetoelectric switching of perpendicular exchange bias in Pt/Co/α-Cr2O3/Pt stacked films 査読有り

    Kentaro Toyoki, Yu Shiratsuchi, Atsushi Kobane, Chiharu Mitsumata, Yoshinori Kotani, Tetsuya Nakamura, Ryoichi Nakatani

    Applied Physics Letters 106 (16) 162404-162404 2015年

    出版者・発行元:{AIP} Publishing

    DOI: 10.1063/1.4918940  

    ISSN:0003-6951

    eISSN:1077-3118

  99. Modifications of Structure and Magnetic Properties of L1(0) MnAl and MnGa Films by Kr+ Ion Irradiation 査読有り

    Daiki Oshima, Masahiro Tanimoto, Takeshi Kato, Yuji Fujiwara, Tetsuya Nakamura, Yoshinori Kotani, Shigeru Tsunashima, Satoshi Iwata

    IEEE TRANSACTIONS ON MAGNETICS 50 (12) 2014年12月

    出版者・発行元:IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/TMAG.2014.2332975  

    ISSN:0018-9464

    eISSN:1941-0069

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    L1(0) phase MnGa and MnAl films with (001) orientation were fabricated by magnetron sputtering. Both films were confirmed to exhibit high perpendicular magnetic anisotropies of 7-8 x 10(6) erg/cc and magnetizations of similar to 450 emu/cc. For the MnGa film, a very flat surface with an average roughness of 0.2 nm was obtained, whereas for the MnAl film, the island growth was confirmed. The X-ray magnetic circular dichroism spectra of these films revealed a significant difference in spectral shape between the perpendicular and inplane magnetized cases. The multiplet peaks appeared in the spectra taken by applying the field normal to the film plane, while such peaks were not clearly seen in the inplane magnetized spectra, possibly owing to the large magnetic anisotropy observed in MnGa and MnAl films. On the other hand, we confirmed a small &lt;L-z&gt;/2&lt;S-z&gt;(&lt;= 0.04) and no systematic change of &lt;L-z&gt;/2&lt;S-z&gt; between the perpendicular and inplane magnetized cases. Finally, 30 keV Kr+ ion irradiation into the films was carried out to modify the magnetic properties of MnGa and MnAl films. In both films, the ion irradiation with a quite low dose of 1x10(14) ions/cm(2) was confirmed to change the magnetism from ferromagnetic to paramagnetic because of the phase change from L1(0) ordered phase to disordered phase. With the significant variation of the magnetism by a low dose of ion irradiation, MnGa and MnAl are considered to be candidates for planar bit-patterned media fabricated by ion irradiation.

  100. Direct observation of ferromagnetism in grain boundary phase of Nd-Fe-B sintered magnet using soft x-ray magnetic circular dichroism 査読有り

    T. Nakamura, A. Yasui, Y. Kotani, T. Fukagawa, T. Nishiuchi, H. Iwai, T. Akiya, T. Ohkubo, Y. Gohda, K. Hono, S. Hirosawa

    Applied Physics Letters 105 (20) 202404-202404 2014年11月17日

    出版者・発行元:{AIP} Publishing

    DOI: 10.1063/1.4902329  

    ISSN:0003-6951

    eISSN:1077-3118

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    We have investigated the magnetism of the grain boundary (GB) phase in a Nd14.0Fe79.7Cu0.1B6.2 sintered magnet using soft x-ray magnetic circular dichroism (XMCD) at the Fe L-2,L-3-edges. Soft XMCD spectra were measured from the fractured surface that was confirmed to be covered with a thin GB phase by Auger electron spectroscopy. The magnetic moment of Fe in the GB phase was estimated to be m(GB) = 1.4 mu(B) at 30 degrees C using the sum rule analysis for XMCD spectra, which is 60% of that of Fe in the Nd2Fe14B compound. The temperature dependence of m(GB) evaluated with reference to Fe in the Nd2Fe14B phase indicated that the Curie temperature of the GB phase is more than 50 degrees C lower compared to that of Nd2Fe14B. (C) 2014 AIP Publishing LLC.

  101. Equilibrium surface magnetization of alpha-Cr2O3 studied through interfacial chromium magnetization in Co/alpha-Cr2O3 layered structures 査読有り

    Kentaro Toyoki, Yu Shiratsuchi, Tetsuya Nakamura, Chiharu Mitsumata, Shotaro Harimoto, Yuichiro Takechi, Takashi Nishimura, Hikaru Nomura, Ryoichi Nakatani

    APPLIED PHYSICS EXPRESS 7 (11) 2014年11月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.7567/APEX.7.114201  

    ISSN:1882-0778

    eISSN:1882-0786

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    We show experimental evidence of the equilibrium surface magnetization of alpha-Cr2O3(0001) by studying chromium magnetization at the Co(111)/alpha-Cr2O3(0001) interface. The soft X-ray magnetic circular dichroism intensity from uncompensated Cr spins was found to be almost independent of the interface roughness and exchange anisotropy energy. Moreover, no exchange bias training effect was found, except in the transition temperature regime, suggesting that the antiferromagnetic spin structure, including the interface spin arrangement, is in equilibrium. Furthermore, the exchange bias polarity was switched by magnetoelectric field cooling, which is also a salient feature of the surface magnetization of alpha-Cr2O3(0001). (C) 2014 The Japan Society of Applied Physics

  102. Mechanism of coercivity enhancement by Ag addition in FePt-C granular films for heat assisted magnetic recording media 査読有り

    B. S. D. Ch. S. Varaprasad, Y. K. Takahashi, J. Wang, T. Ina, T. Nakamura, W. Ueno, K. Nitta, T. Uruga, K. Hono

    APPLIED PHYSICS LETTERS 104 (22) 2014年6月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.4880655  

    ISSN:0003-6951

    eISSN:1077-3118

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    We investigated the Ag distribution in a FePtAg-C granular film that is under consideration for a heat assisted magnetic recording medium by aberration-corrected scanning transmission electron microscope-energy dispersive X-ray spectroscopy and X-ray absorption fine structure. Ag is rejected from the core of FePt grains during the deposition, forming Ag-enriched shell surrounding L1(0)-ordered FePt grains. Since Ag has no solubility in both Fe and Pt, the rejection of Ag induces atomic diffusions thereby enhancing the kinetics of the L1(0)-order in the FePt grains. (C) 2014 AIP Publishing LLC.

  103. Magnetic patterning of FeRh thin films by energetic light ion microbeam irradiation 査読有り

    Tetsuya Koide, Takahiro Satoh, Masashi Kohka, Yuichi Saitoh, Tomohiro Kamiya, Takuo Ohkouchi, Masato Kotsugi, Toyohiko Kinoshita, Tetsuya Nakamura, Akihiro Iwase, Toshiyuki Matsui

    Japanese Journal of Applied Physics 53 (5S1) 05FC06 2014年4月

    出版者・発行元:Japan Society of Applied Physics

    DOI: 10.7567/jjap.53.05fc06  

    ISSN:0021-4922

    eISSN:1347-4065

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    Magnetic patterning of FeRh thin films of various shapes and dimensions by 2MeV H and He ion microbeam irradiation was examined by X-ray magnetic circular dichroism photoemission electron microscopy (XMCD-PEEM) at the photon energy of the Fe L-3 absorption edge. The XMCD-PEEM images clearly show that the various magnetic patterns whose sizes are about 1-2 mu m, can be successfully produced by controlling the scan condition and the size of the ion beam probe. Furthermore, the quantitative analysis of the XMCD-PEEM images reveals that the localized magnetization in the micrometer-sized magnetic patterns significantly depends on the irradiation ion fluence. In addition, the annealing condition is also found to be one of the predominant factors that determine the magnetic state even for the micrometer-sized magnetic patterns. (C) 2014 The Japan Society of Applied Physics

  104. Magnetic structures of FeTiO3-Fe2O3 solid solution thin films studied by soft X-ray magnetic circular dichroism and ab initio multiplet calculations 査読有り

    H. Hojo, K. Fujita, H. Ikeno, T. Matoba, T. Mizoguchi, I. Tanaka, T. Nakamura, Y. Takeda, T. Okane, K. Tanaka

    Applied Physics Letters 104 (11) 2014年3月17日

    DOI: 10.1063/1.4868638  

    ISSN:0003-6951

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    The solid solutions between ilmenite (FeTiO3) and hematite (α-Fe2O3) have recently attracted considerable attention as a spintronic material due to their interesting magnetic and electrical properties. In this study, the electronic and magnetic structures of epitaxially grown 0.6FeTiO3·0.4Fe2O3 solid solution thin films were investigated by combining x-ray absorption near-edge structure (XANES), x-ray magnetic circular dichroism (XMCD) for two different crystallographic projections, and first-principles theoretical calculations. The Fe L-edge XANES and XMCD spectra reveal that Fe is in the mixed-valent Fe2+-Fe3+ states while Fe2+ ions are mainly responsible for the magnetization. Moreover, the experimental Fe L-edge XANES and XMCD spectra change depending on the incident x-ray directions, and the theoretical spectra explain such spectral features. We also find a large orbital magnetic moment, which can originate the magnetic anisotropy of this system. On the other hand, although the valence state of Ti was interpreted to be 4+ from the Ti L-edge XANES, XMCD signals indicate that some electrons are present in the Ti-3d orbital, which are coupled antiparallel to the magnetic moment of Fe2+ ions. © 2014 AIP Publishing LLC.

  105. Observation of a giant Kerr rotation in a ferromagnetic transition metal by M-edge resonant magneto-optic Kerr effect 査読有り

    Sh. Yamamoto, M. Taguchi, M. Fujisawa, R. Hobara, S. Yamamoto, K. Yaji, T. Nakamura, K. Fujikawa, R. Yukawa, T. Togashi, M. Yabashi, M. Tsunoda, S. Shin, I. Matsuda

    PHYSICAL REVIEW B 89 (6) 2014年2月

    出版者・発行元:AMER PHYSICAL SOC

    DOI: 10.1103/PhysRevB.89.064423  

    ISSN:1098-0121

    eISSN:1550-235X

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    The M-edge resonant magneto-optical Kerr effect of a transition metal film was measured using rotating analyzer ellipsometry and compared with theoretical calculations based on resonant scattering theory. A large Kerr rotation angle of over 10 degrees was observed at room temperature.

  106. In situ chemical state analysis of buried polymer/metal adhesive interface by hard X-ray photoelectron spectroscopy 査読有り

    Ozawa, K., Kakubo, T., Shimizu, K., Amino, N., Mase, K., Ikenaga, E., Nakamura, T., Kinoshita, T., Oji, H.

    Applied Surface Science 320 177-182 2014年

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.apsusc.2014.09.012  

    ISSN:0169-4332

    eISSN:1873-5584

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    Chemical state analysis of adhesive interfaces is important to understand an adhesion mechanism between two different materials. Although photoelectron spectroscopy (PES) is an ideal tool for such an analysis, the adhesive interfaces must be exposed to the surface because PES is essentially a surface sensitive technique. However, an in situ observation is possible by hard X-ray PES (HA)(PES) owing to its large probing depth. In the present study, HAXPES is applied to investigate the adhesive interface between rubber and brass without exposing the interface. It is demonstrated that copper sulfides formed at the buried rubber/brass interface are distinguished from S-containing species in the rubber overlayer. The chemical state of the buried interface is compared with that of the "exposed" interface prepared by so-called a filter-paper method. (C) 2014 Elsevier B.V. All rights reserved.

  107. Observation and Characterization of Fragile Organometallic Molecules Encapsulated in Single-Wall Carbon Nanotubes 査読有り

    Daisuke Ogawa, Ryo Kitaura, Takeshi Saito, Shinobu Aoyagi, Eiji Nishibori, Makoto Sakata, Tetsuya Nakamura, Hisanori Shinohara

    JOURNAL OF NANOMATERIALS 2014 1 2014年

    出版者・発行元:HINDAWI PUBLISHING CORPORATION

    DOI: 10.1155/2014/539295  

    ISSN:1687-4110

    eISSN:1687-4129

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    Thermally fragile tris(eta(5) -cyclopentadienyl)erbium (ErCp3) molecules are encapsulated in single-wall carbon nanotubes (SWCNTs) with high yield. We realized the encapsulation of ErCp3 with high filling ratio by using high quality SWCNTs at an optimized temperature under higher vacuum. Structure determination based on high-resolution transmission electron microscope observations together with the image simulations reveals the presence of almost free rotation of each ErCp3 molecule in SWCNTs. The encapsulation is also confirmed by X-ray diffraction. Trivalent character of Er ions (i.e., Er3+) is confirmed by X-ray absorption spectrum.

  108. X-ray Magnetic Circular Dichroism Investigation of the Electron Transfer Phenomena Responsible for Magnetic Switching in a Cyanide-Bridged [CoFe] Chain 査読有り

    Michael L. Baker, Yasutaka Kitagawa, Tetsuya Nakamura, Kou Tazoe, Yasuo Narumi, Yoshinori Kotani, Fumichika Iijima, Graham N. Newton, Mitsutaka Okumura, Hiroki Oshio, Hiroyuki Nojiri

    INORGANIC CHEMISTRY 52 (24) 13956-13962 2013年12月

    出版者・発行元:AMER CHEMICAL SOC

    DOI: 10.1021/ic402580n  

    ISSN:0020-1669

    eISSN:1520-510X

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    The cyanide-bridged [CoFe] one-dimensional chain, [Co-II((R)-pabn)][Fe-III(Tp)(CN)(3)](BF4)center dot MeOH center dot 2H(2)O, where (R)-pabn = (R)-N2,N(2')-bis(pyridin-2-ylmethyl)-1,1'-binaphthyl-2,2'-diamine and Tp = hydrotris(pyrazolyl)borate, exhibits magnetic and electric bistabilities originating from an electron transfer coupled spin transition between Fe-CN-Co pairs. The use of L-edge X-ray absorption spectroscopy (XAS) in combination with L-edge X-ray magnetic circular dichroism (XMCD) is explored for the investigation of the electronic structure and magnetization of Co and Fe ions separately, in both diamagnetic and paramagnetic states. It has been established from susceptibility results that the switching between diamagnetic and paramagnetic phases emanates from electron transfer between low spin Fe(II) and Co(III), resulting in low spin Fe(III) (S = 1/2) and high spin Co(II) (S = 3/2). The XAS and XMCD results are consistent with the bulk susceptibility measurements, where greater detail regarding the charge transfer process is determined. The Fe-CN-Co electron transfer pathway is highlighted by a strongly XMCD dependent transition to a cyanide back bonding orbital, giving evidence for strong hybridization with Fe(III) t(2g) orbitals. In addition to thermally induced and photoinduced switching, [CoFe] is found to exhibit a switching by grinding induced dehydration. Analysis of XAS shows that on grinding diamagnetic [CoFe], 75% of metal ions lock into the magnetic Co(II)Fe(III) phase. Density functional theory calculations based on the [CoFe] crystal structure in the magnetic and nonmagnetic phases aid the spectroscopic results and provide a complementary insight into the electronic configuration of the [CoFe] 3d shells, quantifying the change in ligand field around Co and Fe centers on charge transfer.

  109. Investigation of Au and Ag segregation on Fe(001) with soft X-ray absorption 査読有り

    F. Bonell, D. D. Lam, S. Yoshida, Y. T. Takahashi, Y. Shiota, S. Miwa, T. Nakamura, Y. Suzuki

    SURFACE SCIENCE 616 125-130 2013年10月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.susc.2013.05.010  

    ISSN:0039-6028

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    We investigated the X-ray absorption at the Fe L-3 edge of Fe grown on Cr(001), Au(001) and Ag(001). Systematic variations in the absorption were observed depending on the nature of the buffer. They are explained by segregation of Au and Ag during Fe deposition at room temperature. By measuring wedge shaped samples, the segregated amounts could be measured. Taking into account the possible influence of roughness, we find that the segregated amounts of Au and Ag on a 1 nm-thick Fe film are 0.8 +/- 0.3 ML and 2.0 +/- 0.3 ML, respectively. (C) 2013 Elsevier B.V. All rights reserved.

  110. Ferromagnetic amorphous oxides in the EuO-TiO2 system studied by the Faraday effect in the visible region and the x-ray magnetic circular dichroism at the Eu M-4,M-5 and L-2,L-3 edges 査読有り

    Takahiro Kawamoto, Koji Fujita, Hirofumi Akamatsu, Tetsuya Nakamura, Toyohiko Kinoshita, Masaichiro Mizumaki, Naomi Kawamura, Motohiro Suzuki, Yoshiro Kususe, Shunsuke Murai, Katsuhisa Tanaka

    PHYSICAL REVIEW B 88 (2) 2013年7月

    出版者・発行元:AMER PHYSICAL SOC

    DOI: 10.1103/PhysRevB.88.024405  

    ISSN:1098-0121

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    Amorphous Eu2TiO4 and EuTiO3 have been studied by a combination of the Faraday effect in the visible region and polarization-dependent x-ray absorption spectroscopy at the Eu M-4,M-5 and L-2,L-3 edges to examine the role of Eu 4f-5d exchange interactions on the ferromagnetic behavior. The bulk-sensitive x-ray absorption spectra (XAS) for Eu L-2,L-3 edges show that most of the europium ions are present as the divalent state in the amorphous Eu2TiO4 and EuTiO3. The Eu M-4,M-5 edge x-ray magnetic circular dichroism (XMCD) signals, measured for the amorphous Eu2TiO4, dramatically increase upon cooling through the Curie temperature (16 K) determined by a superconducting quantum interference device (SQUID) magnetometer. Sum-rule analysis of the XMCD at Eu M-4,M-5 edges measured at 10 K yields a 4f spin magnetic moment of 6.6 mu(B) per Eu2+ ion. These results confirm that the ferromagnetic properties exclusively arise from 4f spins of Eu2+. In addition, for both the amorphous Eu2TiO4 and EuTiO3, the temperature and magnetic-field dependence of Eu L-2,L-3 edge XMCD signals can be scaled with the corresponding magnetization measured by SQUID, indicating that the 5d magnetic polarization of Eu2+ is involved in the process to cause the ferromagnetic interaction between Eu2+ ions. We further discuss the origin of ferromagnetism in the amorphous system on the basis of the energy diagram of Eu 4f and 5d levels deduced from the Faraday effect in the visible region. From the wavelength dependence of Faraday rotation angles of the amorphous EuO-TiO2 system in comparison with those of the divalent Eu chalcogenides as reported previously, it is found that the magnitude of crystal-field splitting of Eu 5d levels in the former is on the same order as that in the latter, which explains an enhanced ferromagnetic exchange interaction between Eu 4f and 5d states.

  111. X-ray magnetic circular dichroism photoemission electron microscopy of focused ion beam-induced magnetic patterns on iron-rhodium surfaces 査読有り

    Atsushi Tohki, Kazuma Aikoh, Ryoichi Shinoda, Takuo Ohkochi, Masato Kotsugi, Tetsuya Nakamura, Toyohiko Kinoshita, Akihiro Iwase, Toshiyuki Matsui

    NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS 302 51-54 2013年5月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.nimb.2013.03.028  

    ISSN:0168-583X

    eISSN:1872-9584

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    Iron-rhodium (FeRh) thin films were irradiated with a 30 keV Ga ion beam using a focused ion beam system to produce micrometer scale ferromagnetic square dot arrays. Two-dimensional magnetic square dot arrays with dimensions of 30 x 30, 10 x 10, and 5 x 5 mu m were successfully produced on the FeRh surface, which was confirmed by magnetic force microscopy. The results of photoemission electron microscopy combined with X-ray magnetic circular dichroism revealed that the magnetization of the magnetic square dots could be controlled by changing the amount of irradiation. The magnetic domain structure of the magnetic square dots with sides of 5-30 mu m was found to be a single domain structure, which was possibly influenced by the interaction between ferromagnetic and antiferromagnetic interfaces. (C) 2013 Elsevier B.V. All rights reserved.

  112. Reversible change in the oxidation state and magnetic circular dichroism of Fe driven by an electric field at the FeCo/MgO interface 査読有り

    F. Bonell, Y. T. Takahashi, D. D. Lam, S. Yoshida, Y. Shiota, S. Miwa, T. Nakamura, Y. Suzuki

    APPLIED PHYSICS LETTERS 102 (15) 2013年4月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.4802030  

    ISSN:0003-6951

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    The influence of an electric field on an ultrathin FeCo film was investigated by x-ray absorption spectroscopy and magnetic circular dichroism. Measurements were done on sub-millimeter sized pillars, with partial fluorescence yield detection. Fe L-2,L-3 absorption spectra revealed that partial oxidation of Fe occurred during the microfabrication. The oxidation state could be reversibly controlled by an electric field, which also induced variations of the dichroic signal. These results show that electrochemical phenomena may influence the magnetism at a ferromagnet/insulator interface. (C) 2013 AIP Publishing LLC. [http://dx.doi.org/10.1063/1.4802030]

  113. Theoretical Analysis of Experimental Valence and Magnetization Data around the Field- and Temperature-Induced Valence Transitions of EuNi2(Si0.18Ge0.82)(2): Unified Interpretation for the Results from Soft X-ray Absorption, Its Magnetic Circular Dichroism, and Magnetostatic Measurements 査読有り

    Akio Kotani, Tetsuya Nakamura

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN 82 (4) 044710 2013年4月

    出版者・発行元:PHYSICAL SOC JAPAN

    DOI: 10.7566/JPSJ.82.044710  

    ISSN:0031-9015

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    We calculate the valence and the magnetization as functions of magnetic field and temperature for EuNi2(Si0.18Ge0.82)(2) with a single impurity Anderson model (SIAM), taking into account the effects of (i) the first-order nature of field- and temperature-induced valence transitions, (ii) magnetic impurities, and (iii) the Van Vleck paramagnetism for the Eu3+ state, as well as of the mixed valency between the Eu2+ and Eu3+ configurations. The results are in good agreement with recent experimental results by the soft X-ray absorption and X-ray magnetic circular dichroism experiments and also with available data of magnetization measurements. The present SIAM is an improved version of that used to analyze the field-dependent valence observed by hard X-ray absorption measurements. We point out a serious inconsistency between experimental data for the valence observed by hard X-ray experiments and the magnetization curve, but this inconsistency is removed by the new valence data observed by soft X-ray experiments.

  114. Recent Progress of the X-ray Magnetic Circular Dichroism Technique for Element-Specific Magnetic Analysis 査読有り

    Tetsuya Nakamura, Motohiro Suzuki

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN 82 (2) 021006 2013年2月

    出版者・発行元:PHYSICAL SOC JAPAN

    DOI: 10.7566/JPSJ.82.021006  

    ISSN:0031-9015

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    Recent trend of the X-ray magnetic circular dichroism (XMCD) spectroscopy-based technique and the related scientific topics at SPring-8 are reviewed. At the third-generation synchrotron radiation facility, the key developments in the XMCD technique include i) significant improvements in the accuracy and sensitivity of XMCD measurements with a quick helicity switching of circularly polarized X-rays, ii) introduction of extreme conditions (strong pulsed magnetic field and high pressures), and iii) new experimental setup using the high-brilliance X-ray source (micro-focusing, reflection geometry, and high-pressure cells). These achievements have effectively extended the capability of the XMCD technique, a unique magnetic probe with an element-specificity, providing fundamental scientific insights in spintronics and magnetic recording devices, magnetic nanoparticles, and magnetism under high-magnetic field and high pressures.

  115. Observation of Micro-Magnetic Structures by Synchrotron Radiation Photoelectron Emission Microscopy 査読有り

    Toyohiko Kinoshita, Kuniaki Arai, Keiki Fukumoto, Takuo Ohkochi, Masato Kotsugi, Fangzhun Guo, Takayuki Muro, Tetsuya Nakamura, Hitoshi Osawa, Tomohiro Matsushita, Taichi Okuda

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN 82 (2) 021005 2013年2月

    出版者・発行元:PHYSICAL SOC JAPAN

    DOI: 10.7566/JPSJ.82.021005  

    ISSN:0031-9015

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    Examples of the application of photoelectron emission microscopy (PEEM) combined with synchrotron radiation excitation are reviewed. In particular, the combination study of PEEM and X-ray magnetic dichroism spectroscopy is very valuable for magnetic domain imaging. According to the demands of the industry, such as the production of magnetic recording media, the application method becomes very important. In this review, several examples of studies using magnetic circular and/or linear dichroism spectroscopy for ferro- and antiferromagnetic materials are introduced. In addition, pump-probe time-resolved PEEM is introduced. These methods allow us to measure the dynamical motion of micro-magnetic structures in mesoscopic size magnets in response to the field pulse in the sub-nanosecond range.

  116. Temperature and magnetic field dependent yb valence in ybrh <inf>2</inf>si<inf>2</inf> observed by x-Ray absorption spectroscopy

    Nakai, H., Ebihara, T., Tsutsui, S., Mizumaki, M., Kawamura, N., Michimura, S., Inami, T., Nakamura, T., Kondo, A., Kindo, K., Matsuda, Y.H.

    Journal of the Physical Society of Japan 82 (12) 2013年

    出版者・発行元:PHYSICAL SOC JAPAN

    DOI: 10.7566/JPSJ.82.124712  

    ISSN:0031-9015

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    The temperature and magnetic field dependences of Yb valence were observed in the heavy fermion compound YbRh2Si2 by X-ray absorption spectroscopy. The measurements revealed that the Yb valence decreases with decreasing temperature in the range from 200 to 2 K and increases with increasing magnetic field in the range from 0 to 33 T without showing an abrupt change in the Yb valence. The Yb valence is in the range from 2.92 to 2.96 depending on temperature and magnetic field. With respect to the valence being 2.92 at 0 T and 2.93 at 33 T in 2 K, YbRh2Si2 is a valence fluctuation compound and does not reach the integer trivalent state at high magnetic field. These results endorse the conventional knowledge that the valence of Yb is very close to the integer value of 3+, decreases with decreasing temperature, and becomes closer to 3+ with increasing magnetic field.

  117. Study on ferromagnetic ordering of FeRh thin films induced by energetic heavy ion irradiation by means of X-ray Magnetic Circular Dichroism 査読有り

    Kazuma Aikoh, Atsushi Tohki, Shuichi Okuda, Yuichi Saitoh, Tomihiro Kamiya, Tetsuya Nakamura, Toyohiko Kinoshita, Akihiro Iwase, Toshiyuki Matsui

    Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms 314 99-102 2013年

    DOI: 10.1016/j.nimb.2013.05.031  

    ISSN:0168-583X

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    We investigated the ion irradiation induced ferromagnetic state of FeRh thin films with 10 MeV I ion beam by the measurements of a superconducting quantum interference device (SQUID) magnetometer as well as of soft X-ray Magnetic Circular Dichroism (XMCD). It was clearly shown in the magnetization loops by SQUID measurements that the ion irradiation induced the ferromagnetic state in the FeRh thin films even below room temperature. This was also confirmed by the Fe L2,3-edge XMCD measurements for the irradiated FeRh film samples. However, we found that the irradiation ion fluence dependence on the magnetization was totally different between two measurement techniques. We also revealed by XMCD sum rule analysis that the ferromagnetism in the ion irradiated FeRh thin films was mainly dominated by the spin moment. © 2013 Elsevier B.V. All rights reserved.

  118. Detailed analysis of spin-dependent quantum interference effects in magnetic tunnel junctions with Fe quantum wells 査読有り

    P. Sheng, F. Bonell, S. Miwa, T. Nakamura, Y. Shiota, S. Murakami, D. D. Lam, S. Yoshida, Y. Suzuki

    APPLIED PHYSICS LETTERS 102 (3) 2013年1月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.4789438  

    ISSN:0003-6951

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    We investigated spin-dependent quantum interference effects in Cr(001)/wedge Fe(001)/MgO(001)/Fe(001) magnetic tunnel junctions by dI/dV measurements. dI/dV intensities were mapped two-dimensionally as a function of applied voltage and Fe thickness, indicating a clear signature of quantum well (QW) states in the ultrathin Fe (001) electrode. However, resonant positions of QW states were systematically shifted by one monolayer when compared with the first-principles calculation results. X-ray absorption spectroscopy and magnetic circular dichroism measurements were also performed. While Fe oxide presence at Fe/MgO interface was ruled out, Fe/Cr intermixing could not be excluded. Hence, controlling the Fe/Cr interface may affect QW state. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4789438]

  119. Origin of strong magnetic anisotropy in L1(0)-FeNi probed by angular-dependent magnetic circular dichroism 査読有り

    Masato Kotsugi, Masaki Mizuguchi, Shigeki Sekiya, Masaichiro Mizumaki, Takayuki Kojima, Tetsuya Nakamura, Hitoshi Osawa, Kenji Kodama, Takumi Ohtsuki, Takuo Ohkochi, Koki Takanashi, Yoshio Watanabe

    JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 326 235-239 2013年1月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.jmmm.2012.09.008  

    ISSN:0304-8853

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    We investigated the origin of strong magnetic anisotropy energy (MAE) in L1(0)-type ordered FeNi phase by angular-dependent magnetic circular dichroism. Our findings showed that the orbital magnetic moment of Fe has a significant angular dependence that exhibits a maximum value at the [001] direction corresponding perpendicular to the plane. The calculated uniaxial anisotropy energy when considering spin-orbit (SO) interaction shows quantitatively good agreement with the volume MAE. We concluded that the orbital anisotropy in 3d Fe electrons results in the strong MAE in L1(0)-FeNi and ascribe this to the spin-orbit interaction via structural ordering. (C) 2012 Elsevier BY. All rights reserved.

  120. Progress in Time-Resolved Photoemission Electron Microscopy at BL25SU, SPring-8: Radiofrequency Field Excitation of Magnetic Vortex Core Gyration 査読有り

    Takuo Ohkochi, Akinobu Yamaguchi, Masato Kotsugi, Hiroshi Hata, Minori Goto, Yukio Nozaki, Tetsuya Nakamura, Hitoshi Osawa, Toyohiko Kinoshita

    JAPANESE JOURNAL OF APPLIED PHYSICS 51 (12) 128001 2012年12月

    出版者・発行元:JAPAN SOC APPLIED PHYSICS

    DOI: 10.1143/JJAP.51.128001  

    ISSN:0021-4922

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    We developed a system to carry out time-resolved photoemission electron microscopy under RF excitation at the BL25SU beamline in SPring-8. RF fields of up to similar to 42MHz could be applied to microsized magnetic disks with a power loss of less than 0.9 dB. We performed time-resolved real-space observations of the gyrotropic motion of the magnetic vortex core in Ni81Fe19 disks under an RF magnetic field. We confirmed that significant core gyrations can be seen only when the resonant frequency of the disks matches with the excitation frequency of the system. (C) 2012 The Japan Society of Applied Physics

  121. X-ray Spectroscopies in Pulsed High Magnetic Fields: New Frontier with Flying Magnets and Rolling Capacitor Banks 査読有り

    Y. Narumi, T. Nakamura, T. Kinoshita, Y. H. Matsuda, H. Nojiri

    Synchrotron Radiation News 25 (6) 12-17 2012年11月

    DOI: 10.1080/08940886.2012.736833  

    ISSN:0894-0886 1931-7344

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    A magnetic field is a powerful and precise tuning key for states of matters. It induces various new states with unexpected magnetic, electronic, and crystallographic properties. On the other hand, X-rays are widely used as one of the most powerful means to investigate crystal structures, electronic states, and magnetic phases in varieties of materials. However, the combination of these two tools has been very rare due to technical difficulties. © 2012 Copyright Taylor and Francis Group, LLC.

  122. Status of pump-probe time-resolved photoemission electron microscopy at SPring-8 査読有り

    T. Kinoshita, T. Ohkochi, H. Osawa, K. Arai, K. Fukumoto, T. Okuda, M. Kotsugi, T. Muro, T. Nakamura, T. Matsushita

    JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA 185 (10) 389-394 2012年10月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.elspec.2012.02.006  

    ISSN:0368-2048

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    The present status and the recent progress of pump-probe time-resolved photoemission electron microscopy at SPring-8 are introduced. Combining the variety of bunch operation modes available at the SPring-8 storage ring with ultra-short excitation sources including pulsed magnetic fields, electric fields and lasers, the element-specific time evolution of materials in response to the excitation can be observed with spatial and temporal resolutions of (50-300) nm and (40-100) ps, respectively, with repetition frequencies of up to 42 MHz. By using the magnetic circular dichroism effect, the domain motion of sub-micron sized magnetic areas can be observed. The time evolution of electronic structures in local areas can also be studied. The experimental setups and representative activities are described. (C) 2012 Elsevier B.V. All rights reserved.

  123. Soft-X-ray Magnetic Circular Dichroism under Pulsed High Magnetic Fields at Eu M-4,M-5 Edges of Mixed Valence Compound EuNi2(Si0.18Ge0.82)(2) 査読有り

    Tetsuya Nakamura, Toko Hirono, Toyohiko Kinoshita, Yasuo Narumi, Misaki Hayashi, Hiroyuki Nojiri, Akihiro Mitsuda, Hirofumi Wada, Kenji Kodama, Koichi Kindo, Akio Kotani

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN 81 (10) 103705 2012年10月

    出版者・発行元:PHYSICAL SOC JAPAN

    DOI: 10.1143/JPSJ.81.103705  

    ISSN:0031-9015

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    By applying our new experimental technique of X-ray absorption spectroscopy (XAS) and its X-ray magnetic circular dichroism (XMCD) in the soft-X-ray region under high pulsed magnetic fields of up to 21.3 T, we measured the XAS and XMCD spectra at the Eu M-4,M-5 edges of EuNi2(Si0.18Ge0.82)(2). The measured spectra are analyzed by taking into account the atomic multiplet structures to clarify the mixed valence properties, which are caused by the hybridization between Eu2+ and Eu3+ configurations. We obtain the field dependence of the average valence number from the XAS spectra and that of the magnetizations of Eu2+ and Eu3+ components separately using the spin and orbital sum rules from the XMCD spectra. These results are in good agreement with theoretical ones calculated with a modified single-impurity Anderson model. The present study reveals the key to solving a puzzling problem that was posed in previous XAS and XMCD experiments in the hard-X-ray region.

  124. Measurement of Magnetic Exchange in Ferromagnet-Superconductor La2/3Ca1/3MnO3/YBa2Cu3O7 Bilayers 査読有り

    S. R. Giblin, J. W. Taylor, J. A. Duffy, M. W. Butchers, C. Utfeld, S. B. Dugdale, T. Nakamura, C. Visani, J. Santamaria

    PHYSICAL REVIEW LETTERS 109 (13) 2012年9月

    出版者・発行元:AMER PHYSICAL SOC

    DOI: 10.1103/PhysRevLett.109.137005  

    ISSN:0031-9007

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    The existence of coherent magnetic correlations in the normal phase of cuprate high-temperature superconductors has proven difficult to measure directly. Here we report on a study of ferromagnetic-superconductor bilayers of La2/3Ca1/3MnO3/YBa2Cu3O7 (LCMO/YBCO) with varying YBCO layer thicknesses. Using x-ray magnetic circular dichroism, we demonstrate that the ferromagnetic layer induces a Cu magnetic moment in the adjacent high-temperature superconductor. For thin samples, this moment exists at all temperatures below the Curie temperature of the LCMO layer. However, for a YBCO layer thicker than 12 unit cells, the Cu moment is suppressed for temperatures above the superconducting transition, suggesting this to be a direct measurement of magnetic coherence in the normal state of a superconducting oxide.

  125. Microscopic and Spectroscopic Studies of Light-Induced Magnetization Switching of GdFeCo Facilitated by Photoemission Electron Microscopy 査読有り

    Takuo Ohkochi, Hidenori Fujiwara, Masato Kotsugi, Arata Tsukamoto, Kuniaki Arai, Shinji Isogami, Akira Sekiyama, Jun'ichi Yamaguchi, Kazuaki Fukushima, Roman Adam, Claus M. Schneider, Tetsuya Nakamura, Kenji Kodama, Masakiyo Tsunoda, Toyohiko Kinoshita, Shigemasa Suga

    JAPANESE JOURNAL OF APPLIED PHYSICS 51 (7) 073001 2012年7月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1143/JJAP.51.073001  

    ISSN:0021-4922

    eISSN:1347-4065

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    By means of soft X-ray photoemission electron microscopy (PEEM), we have for the first time observed spatially and temporally resolved element-specific magnetization switching driven by circularly polarized femtosecond laser pulses. We have confirmed that the magnetization switching depending on the helicity of the circularly polarized laser occurs in the region where the spin temperature is raised appropriately. It is also found that the electronic states in the irradiated region remain unchanged even after millions magnetization reversal cycles. (C) 2012 The Japan Society of Applied Physics

  126. Isothermal switching of perpendicular exchange bias by pulsed high magnetic field 査読有り

    Yu Shiratsuchi, Kohei Wakatsu, Tetsuya Nakamura, Hiroto Oikawa, Satoru Maenou, Yasuo Narumi, Kou Tazoe, Chiharu Mitsumata, Toyohiko Kinoshita, Hiroyuki Nojiri, Ryoichi Nakatani

    APPLIED PHYSICS LETTERS 100 (26) 262413 2012年6月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.4731643  

    ISSN:0003-6951

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    Isothermal switching of a perpendicular exchange bias by a strong pulsed magnetic field has been investigated using a Pt/Co/alpha-Cr2O3 thin film system. The switching of the perpendicular exchange bias is accompanied by the spin reversal of interfacial uncompensated antiferromagnetic Cr spins. We have also demonstrated that the switching of the exchange bias is reversible by changing the pulsed magnetic field direction. The mechanism of the demonstrated switching is discussed from the viewpoint of the spin flop transition of the alpha-Cr2O3 layer. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4731643]

  127. Direct observation of twin domains of NiO(100) by x-ray linear dichroism at the O K edge using photoemission electron microscopy 査読有り

    Kuniaki Arai, Taichi Okuda, Arata Tanaka, Masato Kotsugi, Keiki Fukumoto, Takuo Ohkochi, Fangzhun Guo, Tetsuya Nakamura, Tomohiro Matsushita, Takayuki Muro, Masaki Oura, Yasunori Senba, Haruhiko Ohashi, Akito Kakizaki, Toyohiko Kinoshita

    PHYSICAL REVIEW B 85 (17) 2012年5月

    出版者・発行元:AMER PHYSICAL SOC

    DOI: 10.1103/PhysRevB.85.174401  

    ISSN:1098-0121

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    The domain structure of antiferromagnetic (AFM) NiO(100) has been investigated by nonmagnetic x-ray linear dichroism (XLD) at the O K edge using photoemission electron microscopy and linearly polarized x-ray light. The evolution of XLD image contrast as the function of the angle between the crystal orientation and the incident s- or p-polarized light is clearly observed. The angular dependence of the XLD contrast is in good agreement with the calculated x-ray absorption cross section of O 1s to 2p orbital that is deformed anisotropically by the strong hybridization with Ni 3d orbitals. This agreement strongly supports the conclusion that the observed XLD contrast reflects the twin-domain (T-domain) structure of the NiO crystal. By comparing the experimental data with the calculation, it is possible to assign each domain contrast to a specific T-domain in the quantitative manner. The proposed simple and clear way of T-domain assignment will be useful for investigating the magnetic domain structures of NiO and other oxide AFM materials such as FeO, CoO, and CuO, and will be important for understanding the magnetic properties of AFM materials, such as the exchange bias effect.

  128. Three-dimensional spin orientation in antiferromagnetic domain walls of NiO studied by x-ray magnetic linear dichroism photoemission electron microscopy 査読有り

    Kuniaki Arai, Taichi Okuda, Arata Tanaka, Masato Kotsugi, Keiki Fukumoto, Takuo Ohkochi, Tetsuya Nakamura, Tomohiro Matsushita, Takayuki Muro, Masaki Oura, Yasunori Senba, Haruhiko Ohashi, Akito Kakizaki, Chiharu Mitsumata, Toyohiko Kinoshita

    PHYSICAL REVIEW B 85 (10) 104418 2012年3月

    出版者・発行元:AMER PHYSICAL SOC

    DOI: 10.1103/PhysRevB.85.104418  

    ISSN:1098-0121

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    A determination of the three-dimensional spin directions in all types of domain walls (DWs) of antiferromagnetic NiO has been successfully performed by photoemission electron microscopy combined with x-ray magnetic linear dichroism (XMLD), both for s- and p-polarized light. By comparing the azimuthal angle dependence of the XMLD contrast in the DWs with cluster model calculations which include the crystal symmetry and full-multiplet splitting, we determine the spin structures in the {001} T walls, {011} T walls, 120 degrees S walls, and 180 degrees S walls. In some cases, distinct S walls are not formed between two adjacent S domains, and the spin direction changes gradually over a wide range of the S domain structures. In the S walls, the spin direction is parallel to the magnetic easy {111} plane. These spin configurations arise from the large difference in anisotropy energy between the in-plane and out-of-plane directions. Unexpectedly large widths in the several hundred nanometer range were observed for all the DWs. This also shows that NiO has a small magnetocrystalline anisotropy energy. Together with Monte Carlo simulation results, the qualitative phenomena concerning the wall energies are discussed. We further investigated the difference in wall energy between the {001} T wall and the {011} T wall. From the Monte Carlo simulation and an experimental study of heating effects, it is revealed that the {001} T wall energy is smaller than the {011} T wall energy.

  129. MFM and PEEM observation of micrometre-sized magnetic dot arrays fabricated by ion-microbeam irradiation in FeRh thin films 査読有り

    K. Aikoh, A. Tohki, T. Matsui, A. Iwase, T. Satoh, K. Takano, M. Kohka, Y. Saitoh, T. Kamiya, T. Ohkochi, M. Kotsugi, T. Nakamura, T. Kinoshita

    JOURNAL OF SYNCHROTRON RADIATION 19 (2) 223-226 2012年3月

    出版者・発行元:WILEY-BLACKWELL

    DOI: 10.1107/S0909049511054057  

    ISSN:0909-0495

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    FeRh thin films were irradiated with a 10 MeV iodine ion microbeam to produce micrometre-scale ferromagnetic microstructures by modifying the local magnetic character from antiferromagnetism to ferromagnetism using ion-microbeam irradiation. Two-dimensional magnetic dot arrays of dimensions similar to 2 mu m x 4 mu m as well as 10 mu m x 10 mu m were successfully produced on the FeRh surface, which was confirmed by magnetic force microscopy (MFM). The results of photoemission electron microscopy (PEEM) combined with X-ray magnetic circular dichroism reveal that the easy axis of the magnetization of the ion-beam-irradiated ferromagnetism in the FeRh thin films lies in the film planes along the &lt; 001 &gt; direction of the MgO substrates.

  130. High-order Ho multipoles in HoB2C2 observed with soft resonant x-ray diffraction 査読有り

    A. J. Princep, A. M. Mulders, E. Schierle, E. Weschke, J. Hester, W. D. Hutchison, Y. Tanaka, N. Terada, Y. Narumi, T. Nakamura

    JOURNAL OF PHYSICS-CONDENSED MATTER 24 (7) 075602 2012年2月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0953-8984/24/7/075602  

    ISSN:0953-8984

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    Soft resonant x-ray Bragg diffraction (SRXD) at the Ho M-4,M-5 edges has been used to study Ho 4f multipoles in the combined magnetic and orbitally ordered phase of HoB2C2. A full description of the energy dependence for both sigma and pi incident x-rays at two different azimuthal angles, as well as the ratio I-sigma/I-pi as a function of azimuthal angle for a selection of energies, allows a determination of the higher order multipole moments of rank 1 (dipole) to 6 (hexacontatetrapole). The Ho 4f multipole moments have been estimated, indicating a dominant hexadecapole (rank 4) order with an almost negligible influence from either the dipole or the octupole magnetic terms. The analysis incorporates both the intra-atomic magnetic and quadrupolar interactions between the 3d core and 4f valence shells as well as the interference of contributions to the scattering that behave differently under time reversal. Comparison of SRXD, neutron diffraction and non-resonant x-ray diffraction shows that the magnetic and quadrupolar order parameters are distinct. The (001/2) component of the magnetic order exhibits a Brillouin type increase below the orbital ordering temperature T-Q, while the quadrupolar order increases more sharply. We conclude that the quadrupolar interaction is strong, but quadrupolar order only occurs when the magnetic order gives rise to a quasi-doublet ground state, which results in a lock-in of the orbitals at T-Q.

  131. Valence fluctuation in YbAgCu <sub>4</sub> at high magnetic fields 査読有り

    Y.H. Matsuda, T. Nakamura, J.-L. Her, K. Kindo, S. Michimura, T. Inami, M. Mizumaki, N. Kawamura, M. Suzuki, B. Chen, H. Ohta, K. Yoshimura

    Journal of the Physical Society of Japan 81 (1) 015002/1-2 2012年1月

    出版者・発行元:The Physical Society of Japan

    DOI: 10.1143/JPSJ.81.015002  

    ISSN:0031-9015

  132. Disturbance-Free Observation of the Barkhausen Effect in Co/Pt Multilayer by X-ray Fourier Transform Holography 査読有り

    M. Suzuki, T. Nakamura, K. Nomura, S. Isogami, N. Awaji, M. Oura, E. Matsubara, T. Ishikawa, M. Tsunoda

    Journal of the Magnetics Society of Japan 36 (4) 304-307 2012年

    出版者・発行元:The Magnetics Society of Japan

    DOI: 10.3379/msjmag.1206R005   10.3379/msjmag.1206r005  

    ISSN:1882-2924

  133. Detection and in situ switching of unreversed interfacial antiferromagnetic spins in a perpendicular-exchange-biased system 査読有り

    Yu Shiratsuchi, Hayato Noutomi, Hiroto Oikawa, Tetsuya Nakamura, Motohiro Suzuki, Toshiaki Fujita, Kazuto Arakawa, Kazuto Arakawa, Yuichiro Takechi, Hirotaro Mori, Toyohiko Kinoshita, Masahiko Yamamoto, Ryoichi Nakatani

    Physical Review Letters 109 (7) 2012年

    DOI: 10.1103/PHYSREVLETT.109.077202  

    ISSN:0031-9007

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    By using the perpendicular-exchange-biased Pt/Co/α-Cr 2O 3 system, we provide experimental evidence that the unreversed uncompensated Cr spins exist at the Co/α-Cr 2O 3 interface. The unreversed uncompensated Cr spin manifests itself in both the vertical shift of an element-specific magnetization curve and the relative peak intensity of soft-x-ray magnetic circular dichroism spectrum. We also demonstrate an in situ switching of the interfacial Cr spins and correspondingly a reversal of the exchange bias without interfacial atomic diffusion. Such switching shows the direct relationship between the interfacial antiferromagnetic spins and origin of the exchange bias. The demonstrated switching of exchange bias would likely offer a new design of advanced spintronics devices, using the perpendicular-exchange-biased system, with low power consumption and ultrafast operation. © 2012 American Physical Society.

  134. Uncompensated antiferromagnetic moments in Mn-Ir/FM (FM = Ni-Co, Co-Fe, Fe-Ni) bilayers: Compositional dependence and its origin 査読有り

    TakahashiHirokazu, KotaYohei, TsunodaMasakiyo, NakamuraTetsuya, KodamaKenji, SakumaAkimasa, TakahashiMigaku

    Journal of Applied Physics 110 (12) 123920 2011年12月

    出版者・発行元:None

    DOI: 10.1063/1.3672450  

    ISSN:0021-8979

    eISSN:1089-7550

  135. Direct observation of spin configuration in an exchange coupled Fe/NiO(100) system by x-ray magnetic circular- and linear- dichroism photoemission electron microscope 査読有り

    Kuniaki Arai, Taichi Okuda, Arata Tanaka, Keiki Fukumoto, Takahide Hasegawa, Tetsuya Nakamura, Tomohiro Matsushita, Takayuki Muro, Akito Kakizaki, Toyohiko Kinoshita

    JOURNAL OF APPLIED PHYSICS 110 (8) 084306 2011年10月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.3647776  

    ISSN:0021-8979

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    Three dimensional spin configuration in an exchange coupled Fe/NiO(100) system is investigated using a combination of photoemission electron microscopy and magnetic linear- and circular dichroism spectroscopy in the soft-x-ray range. By comparing the experimental image contrasts with a cluster model calculation including the crystal symmetry, we have successfully determined the spin configuration of the bulk antiferromagnetic NiO substrate. The easy axes of the outermost ferromagnetic Fe film and the ferromagnetic interface corresponding to the three kinds of spin axes of the antiferromagnetic NiO substrate have been assigned. We also observe that the magnetic field amplitude required for magnetization reversal depends on these initial easy axes directions. These findings are strongly related to the mechanism of exchange bias phenomena. (C) 2011 American Institute of Physics. [doi:10.1063/1.3647776]

  136. Triakontadipole and high-order dysprosium multipoles in the antiferromagnetic phase of DyB2C2 査読有り

    A. J. Princep, A. M. Mulders, U. Staub, V. Scagnoli, T. Nakamura, A. Kikkawa, S. W. Lovesey, E. Balcar

    JOURNAL OF PHYSICS-CONDENSED MATTER 23 (26) 266002 2011年7月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0953-8984/23/26/266002  

    ISSN:0953-8984

    eISSN:1361-648X

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    Resonant soft x-ray Bragg diffraction at the Dy M-4,M-5 edges has been used to study Dy multipoles in the combined magnetic and orbitally ordered phase of DyB2C2. The analysis incorporates both the intra-atomic magnetic and quadrupolar interactions between the 3d core and 4f valence shells. Additionally, we introduce to the formalism the interference of magnetic and nonmagnetic oscillators. This allows a determination of the higher-order multipole moments of rank 1 (dipole) to 6 (hexacontatetrapole). The strength of the Dy 4f multipole moments have been estimated as being up to 80% of the quadrupolar moment.

  137. Magnetic state of Mn3CuN explored by soft x ray magnetic circular dichroism 査読有り

    K. Takenaka, T. Shibayama, A. Ozawa, T. Hamada, T. Nakamura, K. Kodama, T. Kinoshita

    JOURNAL OF APPLIED PHYSICS 110 (2) 023909 2011年7月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.3614587  

    ISSN:0021-8979

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    The tetragonally distorted antiperovskite Mn3CuN exhibits large magnetostriction of up to 2000 ppm, due to the ferromagnetic shape memory effect. Magnetocrystalline anisotropy, which is deeply involved in the magnetostriction, is investigated for Mn3CuN via quantitative evaluation of spin and orbital magnetic moments using soft x ray magnetic circular dichroism. Although Cu and Mn have finite magnetic contributions, the Cu contribution may be too small to dominate the magnetism of Mn3CuN. The orbital magnetic moment of Mn is found to be negligibly small, suggesting small magnetocrystalline anisotropy. Even with small magnetocrystalline anisotropy, the system exhibits ferromagnetic shape memory effects, presumably because the simultaneously small crystallographic anisotropy enhances the magnetic shear stress acting across the twinning plane. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3614587]

  138. An XMCD-PEEM study on magnetized Dy-doped Nd-Fe-B permanent magnets 査読有り

    R. Yamaguchi, K. Terashima, K. Fukumoto, Y. Takada, M. Kotsugi, Y. Miyata, K. Mima, S. Komori, S. Itoda, Y. Nakatsu, M. Yano, N. Miyamoto, T. Nakamura, T. Kinoshita, Y. Watanabe, A. Manabe, S. Suga, S. Imada

    IBM JOURNAL OF RESEARCH AND DEVELOPMENT 55 (4) 12:1-12:6 2011年7月

    出版者・発行元:IBM CORP

    DOI: 10.1147/JRD.2011.2159148  

    ISSN:0018-8646

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    We have succeeded in developing a method for photoemission electron microscopy (PEEM) on fully magnetized ferromagnetic bulk samples and have applied this technique to Dy-doped Nd-Fe-B permanent magnets. Remanence magnetization of the sample was approximately 1.2 T, and its dimension was 3 x 3 x 3 mm(3). By utilizing a yoke as an absorber of the stray magnetic field from the sample, we can obtain well-focused PEEM images of magnetized samples. We have observed not only chemical distributions to visualize Dy-rich and Dy-poor areas but also magnetic domains by x-ray magnetic circular dichroism. The formation of reversed magnetic domains is strongly suppressed at room temperature by Dy-doping. As the temperature of the Dy-doped sample is raised, starting from room temperature, the reversed magnetic domains first grow along the magnetization easy axis. Next, above approximately 80 degrees C, the shapes of reversed domains start to expand in the direction perpendicular to the easy axis. Above approximately 85 degrees C, the reversed domains cover more than half of the field of view of 30 mu m. More importantly, the reversed magnetic domains tend to nucleate or extend in Dy-poor regions. We discuss the relationship between the chemical distribution and the magnetic domain structure.

  139. Soft X-ray Magnetic Circular Dichroism of a CoFe/MnIr Exchange Bias Film under Pulsed High Magnetic Field 査読有り

    Tetsuya Nakamura, Yasuo Narumi, Toko Hirono, Misaki Hayashi, Kenji Kodama, Masakiyo Tsunoda, Shinji Isogami, Hirokazu Takahashi, Toyohiko Kinoshita, Koichi Kindo, Hiroyuki Nojiri

    APPLIED PHYSICS EXPRESS 4 (6) 066602 2011年6月

    出版者・発行元:JAPAN SOC APPLIED PHYSICS

    DOI: 10.1143/APEX.4.066602  

    ISSN:1882-0778

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    Soft X-ray magnetic circular dichroism (XMCD) under pulsed high magnetic fields of up to 21 T has been measured using a nondestructive pulse magnet. XMCD effects at the Co and the Mn L(2;3)-edges of a Co(70)Fe(30)/Mn(75)Ir(25) bilayer film have been investigated as an example of a high-magnetic-field XMCD measurement. A total electron yield method is adopted to detect absorption. Absorption is recorded by a 1-MHz time-resolved detection synchronized with a 50-ms high-magnetic-field pulse. Using this method, the XMCD effect is represented by mu(m)(H), a function of magnetic field. (C) 2011 The Japan Society of Applied Physics

  140. Electronic, magnetic, and structural properties of the ferrimagnet Mn 2CoSn 査読有り

    Jürgen Winterlik, Gerhard H. Fecher, Benjamin Balke, Tanja Graf, Vajiheh Alijani, Vadim Ksenofontov, Catherine A. Jenkins, Olga Meshcheriakova, Claudia Felser, Guodong Liu, Shigenori Ueda, Keisuke Kobayashi, Tetsuya Nakamura, Marek Wójcik

    Physical Review B - Condensed Matter and Materials Physics 83 (17) 2011年5月31日

    DOI: 10.1103/PhysRevB.83.174448  

    ISSN:1098-0121 1550-235X

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    The magnetic ground state of the Heusler compound Mn2CoSn was predicted to be nearly half-metallic ferrimagnetic with a high spin polarization by ab initio electronic structure calculations. Mn2CoSn was synthesized, and the magnetic behavior of the compound was studied using a superconducting quantum interference device and x-ray magnetic circular dichroism. The experimental values were found to be in fair accordance with the theoretical predictions. The electronic structure and the crystal structure of Mn2CoSn were characterized comprehensively using x-ray powder diffraction, Sn119 Mössbauer spectroscopy, nuclear magnetic resonance, and hard x-ray photoelectron spectroscopy. © 2011 American Physical Society.

  141. Dynamics of Magnetostatically Coupled Vortices Observed by Time-Resolved Photoemission Electron Microscopy 査読有り

    Kuniaki Arai, Taichi Okuda, Keiki Fukumoto, Masato Kotsugi, Takuo Ohkouchi, Kenji Kodama, Takashi Kimura, Yuichi Haruyama, Tetsuya Nakamura, Tomohiro Matsushita, Hitoshi Osawa, Takayuki Muro, Shinji Matsui, Akito Kakizaki, YoshiChika Otani, Toyohiko Kinoshita

    JAPANESE JOURNAL OF APPLIED PHYSICS 50 (5) 053001 2011年5月

    出版者・発行元:JAPAN SOC APPLIED PHYSICS

    DOI: 10.1143/JJAP.50.053001  

    ISSN:0021-4922

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    The dynamics of magnetostatically coupled vortices in a pair of ferromagnetic micron-sized disks has been observed in real space by pump-probe time-resolved photoemission electron microscopy. It is found that the dynamics of paired vortices is affected by a magnetic dipolar interaction. The displacement of a vortex core from its equilibrium position in the paired vortices during the supply of a magnetic field pulse is smaller than that in the isolated vortex, which is in qualitative agreement with micromagnetic simulation results. Unexpectedly, two eigenfrequencies of the paired vortices are different from each other. When the separation distance between the paired disks is shorter, the difference between the two eigenfrequencies is larger. (C) 2011 The Japan Society of Applied Physics

  142. MCD study on Ce@C-82 and Ce-2@C-80 in the soft-X-ray region 査読有り

    Jun Ishikawa, Tsuneaki Miyahara, Yasuharu Hirato, Hiroyoshi Ishii, Takeshi Kodama, Koichi Kikuchi, Tesuya Nakamura, Kenji Kodama, Daisuke Asakura, Tsuneharu Koide

    JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA 184 (3-6) 284-286 2011年4月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.elspec.2011.01.008  

    ISSN:0368-2048

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    We have measured the temperature dependence of MCD spectra on Ce@C-82 and Ce-2@C-80 in the Ce 3d-4f excitation region. The results show that Ce@C-82 has antiferromagnetic interaction while Ce-2@C-80 has ferromagnetic interaction between Ce magnetic moments which are much smaller than the Hund-ground-state values. (C) 2011 Elsevier B.V. All rights reserved.

  143. 25 Tesla pulsed-high-magnetic-field system for soft X-ray spectroscopy 査読有り

    M. Hayashi, Y. Narumi, H. Nojiri, T. Nakamura, T. Hirono, T. Kinoshita, K. Kodama, K. Kindo

    JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA 184 (3-6) 338-341 2011年4月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.elspec.2010.12.015  

    ISSN:0368-2048

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    We have developed a 25 T pulsed high magnetic field system for soft X-ray Magnetic Circular Dichroism: XMCD. The ultra-high vacuum chamber with a pulse magnet coil is installed. By using a newly developed bipolar capacitor bank, the XMCD of paramagnetic Gd2O3 at the M-5 and the M-4 edges was clearly observed at low temperatures. The present system is capable of measuring XMCD of field induced moments in various compounds including paramagnets and antiferromagnets. (C) 2010 Elsevier B.V. All rights reserved.

  144. Multiple phosphorus chemical sites in heavily phosphorus-doped diamond 査読有り

    Hiroyuki Okazaki, Rikiya Yoshida, Takayuki Muro, Tetsuya Nakamura, Takanori Wakita, Yuji Muraoka, Masaaki Hirai, Hiromitsu Kato, Satoshi Yamasaki, Yoshihiko Takano, Satoshi Ishii, Tamio Oguchi, Takayoshi Yokoya

    APPLIED PHYSICS LETTERS 98 (8) 082107 2011年2月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.3554699  

    ISSN:0003-6951

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    We have performed high-resolution core level photoemission spectroscopy on a heavily phosphorus (P)-doped diamond film in order to elucidate the chemical sites of doped-phosphorus atoms in diamond. P 2p core level study shows two bulk components, providing spectroscopic evidence for multiple chemical sites of doped-phosphorus atoms. This indicates that only a part of doped-phosphorus atoms contribute to the formation of carriers. From a comparison with band calculations, possible origins for the chemical sites are discussed. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3554699]

  145. Repeated magnetic compensation in single crystal of Nd0.8Gd 0.2Al2 and XMCD evidence for reversal in orientation of local moments at second transition 査読有り

    Prasanna D. Kulkarni, A. Thamizhavel, K. Kodama, T. Nakamura, S. Ramakrishnan, A. K. Grover

    AIP Conference Proceedings 1349 (PART A) 1217-1218 2011年

    出版者・発行元:American Institute of Physics Inc.

    DOI: 10.1063/1.3606304  

    ISSN:1551-7616 0094-243X

    eISSN:1551-7616

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    Magnetization studies in Nd1-xTbxAl2 (x≤0.25) series reveal the emergence of two well separated quasi-antiferromagnetic transitions near x∼0.2. XMCD results show reversal in orientation of local moments at the second transition. Low field magnetization in a single crystal of Nd0.8Tb0.2Al 2 has confirmed the occurrence of repeated magnetic compensation. © 2011 American Institute of Physics.

  146. Hall resistance and XMCD measurements across magnetic compensation in Pr0.8Gd0.2Al2 査読有り

    Prasanna D. Kulkarni, A. Thamizhavel, T. Nakamura, S. Ramakrishnan, A. K. Grover

    AIP Conference Proceedings 1349 1197-1198 2011年

    出版者・発行元:American Institute of Physics Inc.

    DOI: 10.1063/1.3606294  

    ISSN:1551-7616 0094-243X

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    Field induced reversal in orientations of magnetic moments is a characteristic of the 'zero magnetization spin-ferromagnets', comprising dissimilar rare earth moments combined with non-magnetic elements. Many interesting features are observed as a result of such a reorientation process. We present the sign reversal in Hall resistance across the magnetic compensation temperature in polycrystalline Pr0.8Gd0.2Al2 alloy and also provide the microscopic evidence via the XMCD measurements for the field-induced reversal in the orientation of Pr and Gd moments in a single crystal sample. © 2011 American Institute of Physics.

  147. Development of Scanning-Type X-ray Fourier Transform Holography 査読有り

    K. Nomura, N. Awaji, S. Doi, S. Isogami, K. Kodama, T. Nakamura, M. Suzuki, M. Tsunoda

    10TH INTERNATIONAL CONFERENCE ON X-RAY MICROSCOPY 1365 277-280 2011年

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.3625358  

    ISSN:0094-243X

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    We developed a scanning-type x-ray Fourier transform holography and applied it to both the soft and hard x-ray regions. For this approach, we prepared the holography mask and the imaging object separately and placed them in contact with each other. In this configuration, the illuminated area can be changed by moving the sample relative to the mask via the translation stage. In this case, an image can be recovered by Fourier inversion of the hologram as in the usual lensless Fourier transform holography. This method also reduces the relative vibration between the mask and sample, and provides good quality images. The method was successfully applied to large-area imaging of magnetic domains in a Co/Pt perpendicular magnetic film with soft x-rays. In addition, cross-sectional imaging of Cu interconnect lines was performed in the hard x-ray region.

  148. Photoemission study of Ca-intercalated graphite superconductor CaC 6 査読有り

    Hiroyuki Okazaki, Rikiya Yoshida, Keisuke Iwai, Kengo Noami, Takayuki Muro, Tetsuya Nakamura, Takanori Wakita, Yuji Muraoka, Masaaki Hirai, Fumiaki Tomioka, Yoshihiko Takano, Asami Takenaka, Masahiro Toyoda, Tamio Oguchi, Takayoshi Yokoya

    Physica C: Superconductivity and its Applications 470 (1) S637-S638 2010年12月

    DOI: 10.1016/j.physc.2009.10.039  

    ISSN:0921-4534

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    In this work, we have performed resonant photoemission studies of Ca-intercalated graphite superconductor CaC6. Using photon energy of the Ca 2p-3d threshold, the photoemission intensity of the peak at Fermi energy (EF) is resonantly enhanced. This result provides spectroscopic evidence for the existence of Ca 3d states at EF, and strongly supports that Ca 3d state plays a crucial role for the superconductivity of this material with relatively high Tc. © 2009 Elsevier B.V. All rights reserved.

  149. X-ray Fourier transform holography using separated holography-mask 査読有り

    N. Awaji, K. Nomura, S. Doi, S. Isogami, M. Tsunoda, K. Kodama, M. Suzuki, T. Nakamura

    Diamond Light Source Proceedings 1 ({SRMS}-7) 2010年11月

    出版者・発行元:Cambridge University Press ({CUP})

    DOI: 10.1017/s204482011000047x  

    ISSN:2044-8201

  150. Spin and orbital Ti magnetism at LaMnO3/SrTiO3 interfaces 査読有り

    J. Garcia-Barriocanal, J. C. Cezar, F. Y. Bruno, P. Thakur, N. B. Brookes, C. Utfeld, A. Rivera-Calzada, S. R. Giblin, J. W. Taylor, J. A. Duffy, S. B. Dugdale, T. Nakamura, K. Kodama, C. Leon, S. Okamoto, J. Santamaria

    NATURE COMMUNICATIONS 1 82 EP 2010年9月

    出版者・発行元:NATURE PUBLISHING GROUP

    DOI: 10.1038/ncomms1080  

    ISSN:2041-1723

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    In systems with strong electron-lattice coupling, such as manganites, orbital degeneracy is lifted, causing a null expectation value of the orbital magnetic moment. Magnetic structure is thus determined by spin-spin superexchange. In titanates, however, with much smaller Jahn-Teller distortions, orbital degeneracy might allow non-zero values of the orbital magnetic moment, and novel forms of ferromagnetic superexchange interaction unique to t(2g) electron systems have been theoretically predicted, although their experimental observation has remained elusive. In this paper, we report a new kind of Ti3+ ferromagnetism at LaMnO3/SrTiO3 epitaxial interfaces. It results from charge transfer to the empty conduction band of the titanate and has spin and orbital contributions evidencing the role of orbital degeneracy. The possibility of tuning magnetic alignment (ferromagnetic or antiferromagnetic) of Ti and Mn moments by structural parameters is demonstrated. This result will provide important clues for understanding the effects of orbital degeneracy in superexchange coupling.

  151. Linear correlation between uncompensated antiferromagnetic spins and exchange bias in Mn–Ir/Co100−xFex bilayers 査読有り

    TsunodaMasakiyo, TakahashiHirokazu, NakamuraTetsuya, MitsumataChiharu, IsogamiShinji, TakahashiMigaku

    Applied Physics Letters 97 (7) 072501 2010年8月

    出版者・発行元:None

    DOI: 10.1063/1.3479500  

    ISSN:0003-6951

  152. Large Area Imaging by Fourier Transform Holography Using Soft and Hard X-rays 査読有り

    Naoki Awaji, Kenji Nomura, Shuuichi Doi, Shinji Isogami, Masakiyo Tsunoda, Kenji Kodama, Motohiro Suzuki, Tetsuya Nakamura

    APPLIED PHYSICS EXPRESS 3 (8) 085201 2010年8月

    出版者・発行元:JAPAN SOC APPLIED PHYSICS

    DOI: 10.1143/APEX.3.085201  

    ISSN:1882-0778

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    We studied a new method for large area imaging by Fourier transform holography in both soft and hard X-ray regions In soft X-ray region, magnetic domain image of the perpendicular magnetized film was observed in the 8 mu m area at an X-ray energy of 778 eV In hard X-ray region, the method was applied to observe both the artificially patterned sample in 7 mu m area and the cross-section of Cu-interconnect-line, at an X-ray energy of 5500 eV The spatial resolution, estimated from the 10 to 90% intensity change, was 42 and 75 nm at 778 and 5500 eV, respectively (C) 2010 The Japan Society of Applied Physics

  153. Fabrication of perpendicularly magnetized magnetic tunnel junctions with [formula omitted] hybrid electrode 査読有り

    T. Hiratsuka, G. Kim, Y. Sakuraba, T. Kubota, K. Kodama, N. Inami, H. Naganuma, M. Oogane, T. Nakamura, K. Takanashi, Y. Ando

    Journal of Applied Physics 107 (9) 2010年5月1日

    DOI: 10.1063/1.3358239  

    ISSN:1089-7550 0021-8979

    eISSN:1089-7550

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    Magnetic tunnel junctions (MTJs) of perpendicularly magnetized [formula omitted] structure were fabricated. In-plane x-ray diffraction measurements and element specific evaluation of magnetic properties using soft x-ray magnetic circular dichroism were carried out to examine quite thin [formula omitted] (CMS) inserted layer between CoPt and MgO interface. Ordered [formula omitted] was successfully fabricated onto [formula omitted] as thin as 1 nm thick, and CMS layer shows perpendicular magnetic anisotropy below 3 nm thick via exchange coupling with CoPt layer. In the MTJ-stacking, epitaxial growth was confirmed except for partial misalignment in the upper FePt layer, and coercive field difference clearly appeared between the bottom and the top ferromagnetic electrodes. © 2010, American Institute of Physics. All rights reserved.

  154. Element-Specific Evaluation of Magnetic Moments in Ferrimagnetic Mn2Val Heusler Epitaxial Thin Films 査読有り

    T.Kubota, K. Kodama, T. Nakamura, Y. Sakuraba, M. Oogane, H. Naganuma, K. Takanashi, Y. Ando

    J. Magn. Soc. Jpn. 34 (2) 100-106 2010年3月

    出版者・発行元:The Magnetics Society of Japan

    DOI: 10.3379/msjmag.1002R0004  

    ISSN:1882-2924

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    We successfully fabricated <i>L</i>2<sub>1</sub>-ordered Mn<sub>2</sub>VAl Heusler thin films and evaluated their ferrimagnetic properties by soft x-ray magnetic circular dichroism (XMCD). The buffer layers and annealing temperatures were varied to prepare the Mn<sub>2</sub>VAl films. We discovered that Mn<sub>2</sub>VAl could be ordered in an <i>L</i>2<sub>1</sub> phase well when it was deposited directly onto an MgO (001) single crystalline substrate. The maximum values of <i>L</i>2<sub>1</sub> and <i>B</i>2 long-range order parameters we obtained were about 0.5 for both phases for samples without a buffer layer, when substrates were heated at 500°C or 600°C. The saturation magnetization (<i>M</i><sub>s</sub>) for these samples was roughly 150 emu/cc. This is rather small compared to that expected from the ideal Slater-Pauling behavior, which might be due to the suppressed degree of <i>L</i>2<sub>1</sub> or <i>B</i>2 ordering. Ferrimagnetism in the Mn<sub>2</sub>VAl, ferrimagnetic coupling between Mn and V moments was clearly observed by using the XMCD technique in well-ordered <i>L</i>2<sub>1</sub>-Mn<sub>2</sub>VAl film as has been predicted in theoretical investigations.

  155. Co-concentration dependence of half-metallic properties in Co–Mn–Si epitaxial films 査読有り

    SakurabaY, HiroseN, OoganeM, NakamuraT, AndoY, TakanashiK

    Applied Physics Letters 96 (9) 092511 2010年3月

    出版者・発行元:None

    DOI: 10.1063/1.3330942  

    ISSN:0003-6951

    eISSN:1077-3118

  156. Soft x-ray magnetic circular dichroism of L2(1)-type Co2FeGa Heusler alloy 査読有り

    R. Y. Umetsu, T. Nakamura, K. Kobayashi, R. Kainuma, A. Sakuma, K. Fukamichi, K. Ishida

    JOURNAL OF PHYSICS D-APPLIED PHYSICS 43 (10) 105001 2010年3月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0022-3727/43/10/105001  

    ISSN:0022-3727

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    Spin and orbital magnetic moments of the L2(1)-type Co2FeGa Heusler alloy have been investigated using x-ray magnetic circular dichroism spectra in the soft x-ray region. From the spectra of the L-2,L-3-edge of Co and Fe, the ratios of the orbital magnetic moment to the spin magnetic moment M-orb/M-spin are estimated to be 0.06 for Co and 0.02 for Fe, in agreement with the available theoretical values. The orbital magnetic moments of these two elements are small in line with theoretical results, reflecting the high symmetry of the L2(1)-type crystal structure. Furthermore, it has been confirmed that the magnetic moment of Ga is induced in the present alloy.

  157. Erratum: “Complete Assignment of Spin Domains in Antiferromagnetic NiO(100) by Photoemission Electron Microscopy and Cluster Model Calculation” 査読有り

    Kuniaki Arai, Taichi Okuda, Arata Tanaka, Masato Kotsugi, Keiki Fukumoto, Masaki Oura, Yasunori Senba, Haruhiko Ohashi, Tetsuya Nakamura, Tomohiro Matsushita, Takayuki Muro, Akito Kakizaki, Toyohiko Kinoshita

    Journal of the Physical Society of Japan 79 (3) 038001 2010年3月

    出版者・発行元:Physical Society of Japan

    DOI: 10.1143/JPSJ.79.038001  

    ISSN:0031-9015

  158. Magnetic Properties of GaGdN Studied by SX-MCD and XAFS 査読有り

    M. Takahashi, Yi-Kai Zhou, T. Nakamura, S. Emura, S. Hasegawa, H. Asahi

    JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM 23 (1) 107-109 2010年1月

    出版者・発行元:SPRINGER

    DOI: 10.1007/s10948-009-0577-3  

    ISSN:1557-1939

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    The element-selected magnetic circular dichroism (MCD) between Gd core states is observed in the soft X-ray region (1150-1250 eV). The dichroism intensity for the transition from the 3d to 4f orbital of the Gd atomic state is very strong and reaches up to about 30% at 15 K. The temperature dependence of the MCD intensity shows a ferromagnetic phase around 50-80 K in addition to the room temperature ferromagnetic phase. Its X-ray absorption near edge structure is different from those of other Gd compounds. It seems to be related to the strength of the ferromagnetic behavior.

  159. Complete Assignment of Spin Domains in Antiferromagnetic NiO(100) by Photoemission Electron Microscopy and Cluster Model Calculation 査読有り

    Kuniaki Arai, Taichi Okuda, Arata Tanaka, Masato Kotsugi, Keiki Fukumoto, Masaki Oura, Yasunori Senba, Haruhiko Ohashi, Tetsuya Nakamura, Tomohiro Matsushita, Takayuki Muro, Akito Kakizaki, Toyohiko Kinoshita

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN 79 (1) 013703 2010年1月

    出版者・発行元:PHYSICAL SOC JAPAN

    DOI: 10.1143/JPSJ.79.013703  

    ISSN:0031-9015

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    Spin domains in bulk NiO have been observed by photoemission electron microscopy combined with X-ray magnetic linear dichroism (XMLD) using s- and p-polarized light. The azimuthal angle dependence of domain contrast at Ni L-2-edge XMLD has been analyzed with a NiO6 cluster model taking into account crystal symmetry and multiplet splitting. The complete assignment of spin domains has been achieved. The results evoke the reconsideration of the domain assignment and XMLD studies based on the existing atomic multiplet theory.

  160. Ferrimagnetism in epitaxially grown Mn2VAl Heusler alloy investigated by means of soft x-ray magnetic circular dichroism 査読有り

    Takahide Kubota, Kenji Kodama, Tetsuya Nakamura, Yuya Sakuraba, Mikihiko Oogane, Koki Takanashi, Yasuo Ando

    APPLIED PHYSICS LETTERS 95 (22) 222503 2009年11月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.3269609  

    ISSN:0003-6951

    eISSN:1077-3118

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    Epitaxially grown Mn2VAl films were fabricated on MgO (001) single crystalline substrates by using a sputtering technique. The resulting Mn2VAl films with substrate temperatures of T-s=500 and 600 degrees C showed an L2(1)-ordered structure. The saturation magnetization was 150 emu/cm(3) at 300 K for a sample with T-s=600 degrees C. Ferrimagnetic coupling between the Mn and V magnetic moments in the L2(1)-Mn2VAl film was clearly demonstrated by soft x-ray magnetic circular dichroism. In previous studies, this coupling was found only in polycrystalline bulk samples examined by nuclear magnetic resonance.

  161. Electronic structure of La1.48Nd0.4Sr0.12CuO4 probed by high- and low-energy angle-resolved photoelectron spectroscopy 査読有り

    T. Claesson, M. Mansson, A. Onsten, M. Shi, Y. Sassa, S. Pailhes, J. Chang, A. Bendounan, L. Patthey, J. Mesot, T. Muro, T. Matsushita, T. Kinoshita, T. Nakamura, N. Momono, M. Oda, M. Ido, O. Tjernberg

    PHYSICAL REVIEW B 80 (9) 094503 2009年9月

    出版者・発行元:AMER PHYSICAL SOC

    DOI: 10.1103/PhysRevB.80.094503  

    ISSN:1098-0121

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    We present angle-resolved photoelectron spectroscopy data probing the electronic structure of the Nd-substituted high-T-c cuprate La1.48Nd0.4Sr0.12CuO4. Data have been acquired at low and high photon energies, h nu=55 and 500 eV, respectively. The two extracted Fermi surfaces show significant differences. The differences can be attributed to either the change in probing depth suggesting dissimilarity of the intrinsic electronic structure between surface and bulk regions, or a considerable c-axis dispersion signaling a strong interlayer coupling. At both photon energies, considerable spectral weight is observed at all points along the Fermi surface and the intensity distribution as well as Fermi-surface shape observed at low as well as high photon energy is markedly different from what has been previously reported for La1.28Nd0.6Sr0.12CuO4 by Zhou [Science 286, 268 (1999)].

  162. The electronic structure of Ca-intercalated superconducting graphite CaC6 査読有り

    H. Okazaki, R. Yoshida, K. Iwai, K. Noami, T. Muro, T. Nakamura, T. Wakita, Y. Muraoka, M. Hirai, F. Tomioka, Y. Takano, A. Takenaka, M. Toyoda, T. Oguchi, T. Yokoya

    PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS 469 (15-20) 1041-1044 2009年8月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.physc.2009.05.172  

    ISSN:0921-4534

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    We have measured Ca-intercalated graphite superconductor CaC6 (T-c = 11.2 K) by soft X-ray photoemission spectroscopy in order to understand the electronic structure. For the valence band, we observed several structures that correspond to those of calculated density of states with the partial density of states of Ca 3d at the Fermi level (E-F). We also observed core level spectra that are a very large asymmetric Ca 2p and asymmetric C 1s for CaC6, suggesting the existence of conduction electrons derived from Ca 3d and a charge transfer from Ca to graphene layer. These results provide spectroscopic evidence for PDOS of Ca 3d at E-F. From a comparison of electronic structure of CaC6 and other graphite intercalation compounds (GICs), we found the difference between CaC6 and other superconducting GICs, which provides deeper understanding of the superconductivity of CaC6. (C) 2009 Elsevier B.V. All rights reserved.

  163. Spectroscopic evidence of the existence of substantial Ca 3d derived states at the Fermi level in the Ca-intercalated graphite superconductor CaC6 査読有り

    H. Okazaki, R. Yoshida, K. Iwai, K. Noami, T. Muro, T. Nakamura, T. Wakita, Y. Muraoka, M. Hirai, F. Tomioka, Y. Takano, A. Takenaka, M. Toyoda, T. Oguchi, T. Yokoya

    PHYSICAL REVIEW B 80 (3) 035420 2009年7月

    出版者・発行元:AMER PHYSICAL SOC

    DOI: 10.1103/PhysRevB.80.035420  

    ISSN:1098-0121

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    We have performed soft x-ray photoemission studies of Ca-intercalated graphite superconductor CaC6 (T-c=11.2 K). The valence-band spectrum shows six main structures, with a peak at the Fermi level (E-F), which correspond to those of calculated DOS. The intensity of the E-F peak is resonantly enhanced at the Ca 2p-3d threshold, providing spectroscopic evidence for the existence of Ca 3d electrons at E-F, which is confirmed experimentally for the first time. The Ca 2p core-level spectrum has a very large asymmetric line shape, which is further possible suggestion of the existence of Ca 3d derived conduction electrons at Ca sites. These results strongly support the picture where Ca 3d derived interlayer band plays a crucial role for the superconductivity of this material with relatively high T-c.

  164. Magnetization profile in the MnIr/CoFe exchange bias system 査読有り

    Shuuichi Doi, Naoki Awaji, Kenji Nomura, Toko Hirono, Tetsuya Nakamura, Hiroaki Kimura

    APPLIED PHYSICS LETTERS 94 (23) 232504 2009年6月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.3153144  

    ISSN:0003-6951

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    The element-specific magnetization profile in the Mn(75)Ir(25)/Co(70)Fe(30) exchange bias system was studied by x-ray resonant magnetic reflectometry using circular polarized soft x rays. From the analysis of reflectivities obtained at Co L(3) and Mn L(3) absorption peak, we found the uncompensated Mn spins located at the MnIr/CoFe interface and in the MnIr bulk region which couples antiferromagnetically and ferromagnetically to the Co spin, respectively. A "pinned" Mn spin which does not rotate with the Co spin was observed at the MnIr/CoFe interface.

  165. Correlation between exchange bias field and domain size of ferromagnetic layer in Mn–Ir/Co–Fe bilayers 査読有り

    TakahashiHirokazu, TsunodaMasakiyo, FukumotoKeiki, NakamuraTetsuya, AraiKuniaki, KinoshitaToyohiko, TakahashiMigaku

    Journal of Applied Physics 105 (7) 07D720 2009年4月

    出版者・発行元:None

    DOI: 10.1063/1.3073659  

    ISSN:0021-8979

    eISSN:1089-7550

  166. Soft x-ray magnetic circular dichroism study of magnetite nanoparticles

    A. Yamasaki, H. Kobori, H. Osawa, T. Nakamura, A. Sugimura

    Journal of Physics: Conference Series 150 (4) 2009年

    出版者・発行元:Institute of Physics Publishing

    DOI: 10.1088/1742-6596/150/4/042235  

    ISSN:1742-6596 1742-6588

    eISSN:1742-6596

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    The magnetic circular dichroism in the soft-x-ray core-level absorption (XMCD) of magnetite nanoparticles has been studied. The XMCD spectrum at the Fe L2,3 edge closely resembles the reported one of bulk single crystals in shape. This suggests that the derived amorphous-like grain boundary and the size effect of the magnetite crystals do not significantly affect the electronic structures and the local magnetism of Fe ions. It is also found that the orbital magnetic moment on Fe ions is rather small or quenched. © 2009 IOP Publishing Ltd.

  167. Ferromagnetism and Luminescence of Diluted Magnetic Semiconductors GaGdN and AlGdN 査読有り

    Shuichi Emura, Masahiro Takahashi, Hiroyuki Tambo, Akira Suzuki, T. Nakamura, Yi-Kai Zhou, Shigehiko Hasegawa, Hajime Asahi

    RARE-EARTH DOPING OF ADVANCED MATERIALS FOR PHOTONIC APPLICATIONS 1111 49-+ 2009年

    出版者・発行元:MATERIALS RESEARCH SOC

    DOI: 10.1557/PROC-1111-D03-01  

    ISSN:0272-9172

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    The magnetic characteristics of the dilute magnetic system GaGdN are investigated mainly by soft-X-ray magnetic circular dichroism (MCD) in the energy range of 1160 - 1240 eV. The strong MCD signals up to 30 % at 15K are observed. The temperature dependence of the signal intensity is not on a simple Curie-Weiss curve but depicts a three-step curve. A step around 40 I 100K suggests a new magnetic phase. The luminescence spectrum of GaGdN at low temperature is divided into three parts consisting of two broad bands around 432 nm and 503 nm and a sharp peak at 652 nm. This sharp line is assigned to the intra-transition of the f - f orbital owing to the weak temperature dependence of the intensity and the peak position. AlGdN grown by molecular beam epitaxy produces luminescence at 318.5 nm. X-ray absorption fine structure is examined to survey the occupancy of the Gd ion in the grown specimens.

  168. Near E-F electronic structure of heavily boron-doped superconducting diamond 査読有り

    H. Okazaki, T. Yokoya, J. Nakamura, N. Yamada, T. Nakamura, T. Muro, Y. Tamenori, T. Matsushita, Y. Takata, T. Tokushima, S. Shin, Y. Takano, M. Nagao, T. Takenouchi, H. Kawarada, T. Oguchi

    JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS 69 (12) 2978-2981 2008年12月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/j.jpcs.2008.06.006  

    ISSN:0022-3697

    eISSN:1879-2553

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    We have performed soft X-ray angle-resolved photoemission spectroscopy (SXARPES) of a heavily boron-doped superconducting diamond film (T-c = 7.2 K) in order to Study the electronic structure near the Fermi level (E-F). Careful determination of measured momentum space that across F point in the Brillouin zone (BZ) and increase of an energy resolution provide further spectroscopic evidence that EF is located at the highly dispersive diamond-like bands, indicating that holes at the top of the diamond-like valence band play an essential role for the conducting properties of the heavily boron-doped superconducting diamond for this boron-doping region (effective carrier concentration of 1.6%). The SXARPES intensities at E-F were also mapped out over BZ to obtain experimental Fermi surface sheets and compared with calculations. Crown Copyright (c) 2008 Published by Elsevier Ltd. All rights reserved.

  169. Magnetic-Domain Structure Analysis of Nd-Fe-B Sintered Magnets Using XMCD-PEEM Technique 査読有り

    Sukeyoshi Yamamoto, Mitsuharu Yonemura, Takanori Wakita, Keiki Fukumoto, Tetsuya Nakamura, Toyohiko Kinoshita, Yoshio Watanabe, Fang Zhun Guo, Masugu Sato, Tomoyuki Terai, Tomoyuki Kakeshita

    MATERIALS TRANSACTIONS 49 (10) 2354-2359 2008年10月

    出版者・発行元:JAPAN INST METALS

    DOI: 10.2320/matertrans.MRA2008141  

    ISSN:1345-9678

    eISSN:1347-5320

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    A combination of X-Ray Magnetic Circular Dichroism and PhotoEmission Electron Microscopy (XMCD-PEEM) was applied to the magnetic domain analysis of Nd-Fe-B sintered magnets. The XMCD-PEEM high-resolution images revealed both the magnetic domain structures and the microstructural morphologies. In the thermally demagnetized state, each grain in a polycrystalline sample exhibits a multidomain structure, which is magnetically coupled across grain boundaries. After the DC field-demagnetization, it changed to a single domain structure. The magnetization vector in each surface grain reversed to the negative direction during the field-demagnetization procedure because of the small coercivity in the surface region. In the present study, we observed this surface domain reversal for the first time by means of XMCD-PEEM imaging method, which is important in order to understand the surface phenomena of Nd-Fe-B magnets. [doi: 10.2320/matertrans.MRA2008141]

  170. Magnetic structure of periodically meandered one-dimensional Fe nanowires 査読有り

    Susumu Shiraki, Hideki Fujisawa, Tetsuya Nakamura, Takayuki Muro, Masashi Nantoh, Maki Kawai

    PHYSICAL REVIEW B 78 (11) 115428 2008年9月

    出版者・発行元:AMER PHYSICAL SOC

    DOI: 10.1103/PhysRevB.78.115428  

    ISSN:1098-0121

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    We study the magnetic structure of perpendicularly magnetized Fe nanowires grown on Au (788) by means of x-ray magnetic circular dichroism. The average size of ferromagnetic domains in the nanowires exponentially decreases with temperature, leading to a steeper decay in magnetization compared to nanoislands of Fe. The temperature dependence of magnetization and domain structures can be well described in terms of local atomic geometry, the number of atomic chains in nanowires, exchange coupling between adjacent spins, and magnetic anisotropy. The nonlinear coverage dependence of the activation energy for the creation of magnetic domains can be explained by overall shape of nanowires, which also implies that the magnetic switching processes are strongly shape dependent at the nanoscale.

  171. Magnetic and electronic Co states in the layered cobaltate GdBaCo2 O5.5-x 査読有り

    M. García-Fernández, V. Scagnoli, U. Staub, A. M. Mulders, M. Janousch, Y. Bodenthin, D. Meister, B. D. Patterson, A. Mirone, Y. Tanaka, T. Nakamura, S. Grenier, Y. Huang, K. Conder

    Physical Review B - Condensed Matter and Materials Physics 78 (5) 2008年8月19日

    DOI: 10.1103/PhysRevB.78.054424  

    ISSN:1098-0121 1550-235X

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    We have performed nonresonant x-ray diffraction, resonant soft and hard x-ray magnetic diffraction, soft x-ray absorption, and x-ray magnetic circular dichroism measurements to clarify the electronic and magnetic states of the Co3+ ions in GdBaCo2 O5.5. Our data are consistent with a Co Py 3+ high-spin (HS) state at the pyramidal sites and a Co Oc 3+ low-spin (LS) state at the octahedral sites. The structural distortion with a doubling of the a axis (2 ap ×2 ap ×2 ap cell) shows alternating elongations and contractions of the pyramids, and indicates that the metal-insulator transition is associated with orbital order in the t2g orbitals of the Co Py 3+ HS state. This distortion corresponds to an alternating ordering of xz and yz orbitals along the a and c axes for the Co Py 3+. The orbital ordering and pyramidal distortion lead to deformation of the octahedra but the Co Oc 3+ LS state does not allow an orbital order to occur for the Co Oc 3+ ions. The soft x-ray magnetic diffraction results indicate that the magnetic moments are aligned in the ab plane but are not parallel to the crystallographic a or b axes. The orbital order and the doubling of the magnetic unit cell along the c axis support a noncollinear magnetic structure. The x-ray magnetic circular dichroism data indicate that there is a large orbital magnetic contribution to the total ordered Co moment. © 2008 The American Physical Society.

  172. High Yield Synthesis and Characterization of the Structural and Magnetic Properties of Crystalline ErCl3 Nanowires in Single-Walled Carbon Nanotube Templates 査読有り

    Ryo Kitaura, Daisuke Ogawa, Keita Kobayashi, Takeshi Saito, Satoshi Ohshima, Tetsuya Nakamura, Hirofumi Yoshikawa, Kunio Awaga, Hisanori Shinohara

    NANO RESEARCH 1 (2) 152-157 2008年8月

    出版者・発行元:TSINGHUA UNIV PRESS

    DOI: 10.1007/s12274-008-8013-8  

    ISSN:1998-0124

    eISSN:1998-0000

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    Crystalline ErCl3 nanowires have been fabricated in single-walled carbon nanotubes (SWCNTs) with high yield (similar to 90%), and the structural and magnetic properties of the resulting ErCl3 nanowires encapsulated in SWCNTs (ErCl3@ SWCNTs) characterized. Encapsulation under high temperature and vacuum using high quality SWCNTs results in a high filling-ratio of ErCl3 nanowires in the SWCNTs. The high filling- ratio of ErCl3 nanowires and the use of highly pure SWCNTs with only a small amount of residual Fe catalyst nanoparticles enabled us to observe the magnetic properties of ErCl3@ SWCNTs. Structure determination based on simulated annealing calculations and high-resolution transmission electron microscope (HRTEM) image simulations revealed that the structure of the ErCl3 nanowires is unusual with respect to the coordination environment of the Eu3+ ions. This work opens up new possibilities to fabricate various metal complex nanowires with high yield and may also be of more general importance in understanding and exploring magnetic properties in low-dimensional magnetic systems.

  173. X-ray magnetic circular dichroism study on ferromagnetic Pd nanoparticles 査読有り

    Y. Oba, H. Okamoto, T. Sato, T. Shinohara, J. Suzuki, T. Nakamura, T. Muro, H. Osawa

    JOURNAL OF PHYSICS D-APPLIED PHYSICS 41 (13) 134024 2008年7月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0022-3727/41/13/134024  

    ISSN:0022-3727

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    An x-ray magnetic circular dichroism (XMCD) experiment was performed for freestanding Pd nanoparticles which were prepared in a high purity atmosphere and showed ferromagnetism. We observed the XMCD signal at Pd M(2,3) absorption edges of nanoparticles. This is clear experimental evidence of ferromagnetic moment in pure Pd. Using the sum rules, the ratio of orbital to spin magnetic moments m(L)/m(S) of similar to 0.1 was obtained. In the x-ray absorption spectrum, the intensities of white lines increased in Pd nanoparticles relative to the bulk. This shows the increase in the number of unoccupied 4d states n(h) which can contribute to the appearance of ferromagnetism in Pd.

  174. Itinerant Ferromagnetism in layered crystals LaCoOX (X = P, As) 査読有り

    H. Yanagi, R. Kawamura, T. Kamiya, Y. Kamihara, M. Hirano, T. Nakamura, H. Osawa, H. Hosono

    Physical Review B 77 (22) 2008年6月20日

    出版者・発行元:American Physical Society

    DOI: 10.1103/PhysRevB.77.224431  

    ISSN:2469-9950

  175. Construction and development of a time-resolved x-ray magnetic circular dichroism-photoelectron emission microscopy system using femtosecond laser pulses at BL25SU SPring-8 査読有り

    Keiki Fukumoto, Tomohiro Matsushita, Hitoshi Osawa, Tetsuya Nakamura, Takayuki Muro, Kuniaki Arai, Takashi Kimura, Yoshichika Otani, Toyohiko Kinoshita

    REVIEW OF SCIENTIFIC INSTRUMENTS 79 (6) 063903 2008年6月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.2937648  

    ISSN:0034-6748

    eISSN:1089-7623

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    A femtosecond pulsed laser system has been installed at the BL25SU soft x-ray beamline at SPring-8 for time-resolved pump-probe experiments with synchronization of the laser pulses to the circularly polarized x-ray pulses. There are four different apparatuses situated at the beamline; for photoemission spectroscopy, two-dimensional display photoelectron diffraction, x-ray magnetic circular dichroism (XMCD) with electromagnetic coils, and photoelectron emission microscopy (PEEM). All four can be used for time-resolved experiments, and preliminary investigations have been carried out using the PEEM apparatus to observe magnetization dynamics in combination with XMCD. In this article, we describe the details of the stroboscopic pump-probe XMCD-PEEM experiment, and present preliminary data. The repetition rate of the laser pulses is set using a pulse selector to match the single bunches of SPring-8's hybrid filling pattern, which consists of several single bunches and a continuous bunch train. Electrons ejected during the bunch train, which do not provide time-resolved signal, are eliminated by periodically reducing the channel plate voltage using a custom-built power supply. The pulsed laser is used to create 300 ps long magnetic field pulses, which cause magnetic excitations in micron-sized magnetic elements which contain magnetic vortex structures. The observed frequency of the motion is consistent with previously reported observations and simulations.

  176. Itinerant ferromagnetism in the layered crystals $\textLaCoOX\phantomůle0.3em0ex(X=\textP,\textAs)$ 査読有り

    Yanagi Hiroshi, Kawamura Ryuto, Kamiya Toshio, Kamihara Yoichi, Hirano Masahiro, Nakamura Tetsuya, Osawa Hitoshi, Hosono Hideo

    Phys. Rev. B 77 (22) 224431 2008年6月

    出版者・発行元:American Physical Society

    DOI: 10.1103/PhysRevB.77.224431  

    ISSN:1098-0121

  177. Element-Specific Magnetic Properties of Di-Erbium Er2@C82 and Er2C2@C82 Metallofullerenes:  A Synchrotron Soft X-ray Magnetic Circular Dichroism Study 査読有り

    Okimoto Haruya, Kitaura Ryo, Nakamura Tetsuya, Ito Yasuhiro, Kitamura Yutaka, Akachi Takao, Ogawa Daisuke, Imazu Naoki, Kato Yuko, Asada Yuki, Sugai Toshiki, Osawa Hitoshi, Matsushita Tomohiro, Muro Takayuki, Shinohara Hisanori

    The Journal of Physical Chemistry C 112 (15) 6103-6109 2008年4月

    出版者・発行元:None

    DOI: 10.1021/jp711776j  

    ISSN:1932-7447

    eISSN:1932-7455

  178. Electronic and magnetic states of Mn2.97Co0.03GaC studied by soft X-ray photoemission and magnetic circular dichroism 査読有り

    Atsushi Matsumoto, Masanori Tsunekawa, Shigemasa Suga, Hirofumi Wada, Takayuki Muro, Tetsuya Nakamura, Shin Imada

    JAPANESE JOURNAL OF APPLIED PHYSICS 47 (3) 1567-1569 2008年3月

    出版者・発行元:JAPAN SOC APPLIED PHYSICS

    DOI: 10.1143/JJAP.47.1567  

    ISSN:0021-4922

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    The electronic and magnetic states of Mn2.97Co0.03GaC are studied by soft X-ray photoelectron spectroscopy (SXPES) and X-ray magnetic circular dichroism (XMCD) in the Mn 2p --&gt; 3d excitation region. On the basis of the XMCD results, the contribution of the orbital magnetic moment to the Mn 3d magnetic moment is evaluated by the XMCD sum rules. The spectra obtained by SXPES show a clear change in electronic states near the Fermi level across the first-order ferromagnetic to antiferromagnetic phase transition. The experimental results are consistent with the theoretically obtained electronic structures of the two phases.

  179. Spin Polarization of Sub-monolayer Cu Embedded in Fe_<70>Co_<30> Films

    Isogami S., Tsunoda M., Nakamura T., TAKAHASHI M.

    Journal of the Magnetics Society of Japan 320 (22) 540-542 2008年

    出版者・発行元:公益社団法人日本磁気学会

    DOI: 10.3379/msjmag.32.540  

    ISSN:1882-2924

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    Spin polarization of Cu embedded in Fe<sub>70</sub>Co<sub>30</sub> films has been investigated by means of transmission x-ray magnetic circular dichroism (XMCD). [Fe<sub>70</sub>Co<sub>30</sub>(<i>d</i><sub>FeCo</sub>) / Cu(<i>d</i><sub>Cu</sub>)]<sub><i>n</i></sub> multilayered films were fabricated on Si-N membrane substrate, fixing total thickness of Fe-Co and Cu layers. Magneto-optical sum-rules were applied to the measured absorption and XMCD spectra to determine quantitatively the spin and orbital moments of Cu. With decreasing the Cu layer thickness, the spin moment of Cu increases but exhibits to be saturated about 0.1 μ<sub>B</sub> / atom. The small value of spin moment (0.1 μ<sub>B</sub>), comparing to that of the 3<i>d</i> transition metals such as Fe and Co, implies that only the top part of 3<i>d</i> down-spin band of Cu is unoccupied in these specimens.

  180. Correlation between spin dependent scattering and impurity polarization in CPP-GMR spin valves with ultra thin Cu inserted Fe-Co layers 査読有り

    S. Isogami, M. Tsunoda, K. Noguchi, T. Nakamura, H. Osawa, M. Takahashi

    Physica Status Solidi (A) Applications and Materials Science 204 (12) 4033-4036 2007年12月

    DOI: 10.1002/pssa.200777306  

    ISSN:1862-6300 1862-6319

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    The correlation between the magnitudes of spin dependent scattering (ΔRA) and impurity polarization was examined in current perpendicular to plane (CPP-) giant magnetoresistance (GMR) films with ultra-thin Cu inserted Fe-Co layers, with changing the chemical compositon of Fe-Co. The enhancing effect of ΔRA by Cu insertion was remarkable for Fe70Co 30 layers in which the body centered cubic structure is maintained against Cu insertion and large spin polarization of dissolved Cu is observed via X-ray magnetic circular dichroism. We thus conclude that the enhancement of spin dependent scattering originates from the spin polarized Cu atoms embedded in Fe-Co alloys. © 2007 WILEY-VCH Verlag GmbH &amp Co. KGaA,.

  181. Enhanced 1520 nm photoluminescence from Er3+ ions in di-erbium-carbide metallofullerenes (Er2C2)@C-82 (isomers I, II, and III) 査読有り

    Yasuhiro Ito, Toshiya Okazaki, Shingo Okubo, Masahiro Akachi, Yutaka Ohno, Takashi Mizutani, Tetsuya Nakamura, Ryo Kitaura, Toshiki Sugai, Hisanori Shinohara

    ACS NANO 1 (5) 456-462 2007年12月

    出版者・発行元:AMER CHEMICAL SOC

    DOI: 10.1021/nn700235z  

    ISSN:1936-0851

    eISSN:1936-086X

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    Di-erbium and di-erbium-carbide endohedral metallofullerenes with a C-82, cage such as Er-2@C-82 (isomers I, II, and III) and (Er2C2)@C-82 (isomers I, II, and III) have been synthesized and chromatographically isolated (99%). The structures of Er-2@C-82 (I II, III) and (Er2C2)@C-82 (I, II, III) metallofullerenes are characterized by comparison with the UV-vis- NIR absorption spectra of (Y2C2)@C-82 (I, II, III), where molecular symmetries of the structures are determined to be C-s, C-2v and C-3v, respectively. Furthermore, enhanced near-infrared photoluminescence (PL) at 1520 nm from Er3+ ions in Er-2@C-2 (I, III) and (Er2C2)@C-82 (I, III) have been observed at room temperature. The PL intensities have been shown to depend on the symmetry of the C-82 cage. In particular, the PL. intensity of (Er2C2)@C-82 (III) has been the strongest among the isomers of Er-2@C-82 and (Er2C2)@C-82. optical measurements indicate that the PL properties of Er-2@C-82 (I, II, III) and (Er2C2)@C-82 (I, II III) correlate strongly with the absorbance at 1520 nm and the HOMO-LUMO energy gap of the C-82 cage.

  182. Magnetism of the endohedral metallofullerenes M@C(82) (M=Gd,Dy) and the corresponding nanoscale peapods: Synchrotron soft x-ray magnetic circular dichroism and density-functional theory calculations 査読有り

    R. Kitaura, H. Okimoto, H. Shinohara, T. Nakamura, H. Osawa

    PHYSICAL REVIEW B 76 (17) 2007年11月

    出版者・発行元:AMER PHYSICAL SOC

    DOI: 10.1103/PhysRevB.76.172409  

    ISSN:1098-0121

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    Synchrotron soft x-ray magnetic circular dichroism (SXMCD) spectroscopy at the Gd and Dy M(5) edges is reported on endohedral metallofullerenes (M@C(82), M=Gd and Dy) and the corresponding nanopeapods [(M@C(82))@SWNT, SWNT represents single wall carbon nanotube] in a temperature range between 10 and 40 K. The magnetic moment has also been determined by theoretical calculations, which are based on the Hartree-Fock approximation with relativistic corrections. Because of the element-specific measurement of SXMCD, magnetization processes of Gd and Dy ions of nanopeapods have been selectively observed. The temperature dependence of magnetic moments of the metallofullerenes and nanopeapods follows the Curie-Weiss law with a small Weiss temperature, indicating that the magnetic interaction between encapsulated rare-earth metal atoms is relatively weak. Although the observed differences in Curie constants and Weiss temperatures between Gd@C(82) and (Gd@C(82))@SWNT are small, those of Dy@C(82) and (Dy@C(82))@SWNT are significant. This observation is consistently explained by charge transfer-induced crystal-field effects.

  183. Degree of circular polarization of soft X-rays emitted from a multi-polarization-mode undulator characterized by means of magnetic circular dichroism measurements 査読有り

    Masaki Oura, Tetsuya Nakamura, Tomoyuki Takeuchi, Yasunori Senba, Haruhiko Ohashi, Katsutoshi Shirasawa, Takashi Tanaka, Masao Takeuchi, Yukito Furukawa, Toko Hirono, Toru Ohata, Hideo Kitamura, Shik Shin

    JOURNAL OF SYNCHROTRON RADIATION 14 (Pt 6) 483-486 2007年11月

    出版者・発行元:BLACKWELL PUBLISHING

    DOI: 10.1107/S0909049507040289  

    ISSN:0909-0495

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    The degree of circular polarization of soft X-rays emitted from the multi-polarization-mode undulator of BL17SU at SPring-8 has been deduced by means of magnetic circular dichroism in core-level X-ray absorption spectroscopy for a ferrimagnetic Gd-Fe-Co amorphous thin film. The results of reference measurements performed using well characterized undulator radiation of BL25SU at SPring-8 have also been utilized. The degrees of circular polarization were presumed for all the available operational modes and were compared with simple theoretical calculations. It was found that the calculated degrees of circular polarization were validated by the measurements reasonably well and will be useful in further experiments at BL17SU.

  184. Probing the valence band structure of Cu2O using high-energy angle-resolved photoelectron spectroscopy 査読有り

    Anneli Onsten, Martin Mansson, Thomas Claesson, Takayuki Muro, Tomohiro Matsushita, Tetsuya Nakamura, Toyohiko Kinoshita, Ulf O. Karlsson, Oscar Tjernberg

    PHYSICAL REVIEW B 76 (11) 115127 2007年9月

    出版者・発行元:AMER PHYSICAL SOC

    DOI: 10.1103/PhysRevB.76.115127  

    ISSN:1098-0121

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    We present angle-resolved photoemission data along the M-Gamma-M direction from a Cu2O(111) single crystal, collected at high photon energies (h nu=619 and 891 eV) and T=100 K. Because of the high photon energies and effective background subtraction, our data give a clear picture of the bulk band structure. The results confirm the existence of a hybridized Cu 3d-Cu 4s state located between the two main Cu 3d and O 2p band regions. Several theoretical studies have predicted the existence of this band, but until now it has not been detected in any photoemission measurements. The experimentally derived band structure is compared to local density approximation calculations with and without the Hubbard potential U. The clear band dispersion in our experimental data has enabled us to extract a refined Hubbard U value, which makes it possible to achieve a better agreement between theoretically calculated bands and experimental data.

  185. Soft X-ray resonant magnetic reflectivity study on induced magnetism in [Fe70Co30/Pd]nsuper-lattice films 査読有り

    N. Awaji, K. Noma, K. Nomura, S. Doi, T. Hirono, H. Kimura, T. Nakamura

    Journal of Physics: Conference Series 83 (1) 012034 2007年6月1日

    出版者・発行元:Institute of Physics Publishing

    DOI: 10.1088/1742-6596/83/1/012034  

    ISSN:1742-6596 1742-6588

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    We performed soft x-ray resonant magnetic reflectivity experiments on [FeCo/Pd]n super-lattice films to study the depth profile of magnetization near the interface. From the analysis of the reflectivity measured at the Fe-L IIIabsorption edge, we obtained the magnetization profiles for the samples with different FeCo layer thicknesses. The profiles can be divided into three different zones: (A) Mixed region at the Pd interface where the magnetization decreased due to the structural randomness, (B) Enhanced region where the magnetization increased, and (C) Non-enhanced region. We estimated the thickness where the FeCo magnetization is enhanced by the adjacent Pd layer is about 4 atomic monolayers. © 2007 IOP Publishing Ltd.

  186. Electronic structure and magnetism of one-dimensional Fe monatomic wires on Au(788) investigated with ARPES and XMCD 査読有り

    Hideki Fujisawa, Susumu Shiraki, Masashi Furukawa, Shintaro Ito, Tetsuya Nakamura, Takayuki Muro, Masashi Nantoh, Maki Kawai

    PHYSICAL REVIEW B 75 (24) 245423 2007年6月

    出版者・発行元:AMERICAN PHYSICAL SOC

    DOI: 10.1103/PhysRevB.75.245423  

    ISSN:1098-0121

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    In this study of fabricated one-dimensional (1D) monatomic Fe wires on a Au(788) substrate, electronic and magnetic features are investigated by angle-resolved photoemission spectroscopy (ARPES) and x-ray magnetic circular dichroism (XMCD). The ARPES spectra show little dispersion both in the parallel and perpendicular directions to the wires revealing a strongly localized nature of the Fe 3d electrons. Finite intensity of the XMCD signals has angular dependence reflecting an anisotropic feature of the localized magnetic moments with an easy axis perpendicular to the substrate. Temperature and field dependence of the XMCD signals shows superparamagnetic behavior well described by the 1D Ising model exhibiting large hysteresis below the blocking temperature, which is ruled by the anisotropy energy. Increase of the average size of the spin blocks with reduced temperature enhances the dramatic change of the magnetic properties of the 1D spin system from soft to hard within a narrow temperature range.

  187. Uncompensated antiferromagnetic spins at the interface in Mn–Ir based exchange biased bilayers 査読有り

    TsunodaM, YoshitakiS, AshizawaY, MitsumataC, NakamuraT, OsawaH, HironoT, KimD. Y, TakahashiM

    Journal of Applied Physics 101 (9) 09E510 2007年5月

    出版者・発行元:None

    DOI: 10.1063/1.2710216  

    ISSN:0021-8979

  188. Large magnetic polarization of Ti4+ ions in FeTiO3

    T. Fujii, M. Yamashita, S. Fujimori, Y. Saitoh, T. Nakamura, K. Kobayashi, J. Takada

    Journal of Magnetism and Magnetic Materials 310 (2) e555-e557 2007年3月

    DOI: 10.1016/j.jmmm.2006.10.469  

    ISSN:0304-8853

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    Nominal valence states of Ti ions in FeTiO3 are generally considered to be Ti4+. However, due to the close energy levels between Fe2+ and Ti4+ states, there are some possibilities of intervalence charge transfer from Fe2+ to Ti4+. In order to clarify the real electronic structures of Ti ions in FeTiO3, we performed resonant photoemission spectroscopy (RPES) and X-ray magnetic circular dichroism (XMCD) across the Ti 2p→3d excitation. The RPES spectra clearly indicated the partial density of states derived from the Ti 3d states on the valence band. The Ti 3d states appearing at the top of the valence bands were overlapped with the Fe 3d states. Moreover, the XMCD spectra at Ti L2,3 edges suggested large magnetic polarization of Ti ions in FeTiO3 in spite of nonmagnetic natures of Ti4+ ions in common sense. The Ti ions in FeTiO3 seemed to have some 3d electron densities caused by the electron transfer from the Fe 3d t2g↓ states. © 2006 Elsevier B.V. All rights reserved.

  189. Temperature and magnetic. eld dependence of the soft X-ray magnetic circular dichroism intensity for the Mn-L-3 edge of MnFeP0.78Ge0.22 査読有り

    Masanori Tsunekawa, Shin Imada, Atsushi Matsumoto, Atsushi Yamasaki, Shigemasa Suga, Benjamin Schmid, Hirosato Higashimichi, Yoshiro Hattori, Tetsuya Nakamura, Ekkes Brueck

    JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 310 (2) E1010-E1011 2007年3月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.jmmm.2006.10.977  

    ISSN:0304-8853

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    Soft X-ray magnetic circular dichroism (XMCD) measurements were performed at the L-3 edge of manganese for MnFeP0.78Ge0.22 at 290 and 279 K. Temperature and magnetic field dependence of the XMCD intensity was clearly observed, which is consistent with that of the magnetization measurements as reported for the related MnFe(P,As) systems. Our results suggest that the unoccupied electronic states of Mn above the Fermi level would be modified through the first-order field-induced magnetic transition. (C) 2006 Elsevier B.V. All rights reserved.

  190. Dimensionality of the electronic states in Nd0.45Sr0.55MnO3 studied by soft X-ray photoemission 査読有り

    H. Fujiwara, A. Sekiyama, M. Yano, T. Murakawa, T. Miyamachi, M. Tsunekawa, S. Imada, B. Schmid, M. Sing, A. Higashiya, T. Muro, T. Nakamura, K. Noda, H. Kuwahara, S. Miyasaka, Y. Tokura, S. Suga

    JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS 310 (2) 816-818 2007年3月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.jmmm.2006.10.706  

    ISSN:0304-8853

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    The electronic states of Nd0.45Sr0.55MnO3 in the two-dimensional metal phase have been revealed by the high-resolution Mn 2p-3d resonant photoemission. The vanishingly weak intensity at E-F indicates an anomalous metal due to the two-dimensionality of the electronic states. (c) 2006 Elsevier B.V. All rights reserved.

  191. Development and trial measurements of hard X-ray photoelectron emission microscope 査読有り

    T. Taniuchi, T. Wakita, M. Takagaki, N. Kawamura, M. Suzuki, T. Nakamura, K. Kobayashi, M. Kotsugi, M. Oshima, H. Akinaga, H. Muraoka, K. Ono

    SYNCHROTRON RADIATION INSTRUMENTATION, PTS 1 AND 2 879 1353-+ 2007年

    出版者・発行元:AMER INST PHYSICS

    ISSN:0094-243X

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    Photoelectron emission microscope (PEEM) study is performed using hard x-ray illumination. We have successfully obtained images with high spatial resolution of 40 nm with hard x-rays. Spectro-microscopy of Co micropatterns on Si substrates, which can be applied to XAFS measurements on a minute scale by PEEM. Magnetic imaging has been demonstrated at the Pt L-edges on perpendicular magnetic recording pattern of CoCrPt alloy. These results are the first step toward a new spectroscopic microscopy and magnetic imaging in a hard x-ray region.

  192. X-ray magnetic circular dichroism studies of the enhancement of Fe spin moment in (Fe70 Co30 Pd)n superlattice films with high saturation magnetization 査読有り

    Kenji Noma, Hitoshi Kanai, Yuji Uehara, Tetsuya Nakamura, Hitoshi Osawa, Shuichi Doi, Kenji Nomura, Naoki Awaji

    Journal of Applied Physics 101 (9) 2007年

    DOI: 10.1063/1.2711172  

    ISSN:0021-8979

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    It was reported that magnetic materials reveal a high saturation magnetization above 2.45 T, which is known as the highest saturation magnetization of Fe70 Co30 alloy in nature. An (Fe70 Co30 Pd)n superlattice film with optimized sublayer thickness showed that the saturation magnetization of the Fe70 Co30 sublayers and that of the whole film were 2.66 and 2.57 T, respectively. These values were defined as an average of the magnetic moments of Fe, Co, and Pd atoms, and the contribution ratio of each element to the magnetization improvement is still not clear. X-ray magnetic circular dichroism measurement enabled a direct estimation of the individual moments of Fe, Co, and Pd atoms in the superlattice film and it clarified that the magnetization improvement in the superlattice films was induced by an enhancement of Fe spin moment dominantly in the Fe70 Co30 sublayers. These results follow the other theoretical and experimental results about an enhancement of the Fe moment of atoms which are laminated with Pd layers. © 2007 American Institute of Physics.

  193. Status of the twin helical undulator soft x-ray beamline at SPring-8: Performance for circular dichroism measurements 査読有り

    T. Muro, T. Nakamura, T. Matsushita, T. Wakita, K. Fukumoto, H. Kimura, T. Hirono, T. Kinoshita, T. Hara, K. Shirasawa, M. Takeuchi, H. Kitamura

    SYNCHROTRON RADIATION INSTRUMENTATION, PTS 1 AND 2 879 571-+ 2007年

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.2436125  

    ISSN:0094-243X

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    The status of the soft x-ray beamline BL25SU at SPring-8 is reported. The beamline performance for circular dichroism measurements using the helicity switching of helical undulator radiation is focused on. Light spots on a sample of the opposite helicities have been observed with a photoelectron emission microscope. The vertical profiles of the spots have almost the same line shape and a positional difference of similar to 0.5 mu m. The horizontal spot positions coincide, but the horizontal spot widths are different by similar to 7%. The energy difference of the monochromatized light between the opposite helicities has been estimated to be less than or comparable to 1 meV in the Ne 1s absorption region. The kick angle of the kicker magnets has been increased from 0.2 to 0.3 mrad to avoid penetration of the higher harmonics.

  194. Valence band electronic structures of heavily boron-doped superconducting diamond studied by synchrotron photoemission spectroscopy 査読有り

    Takayoshi Yokoya, Tetsuya Nakamura, Tomohiro Matsushita, Takayuki Muro, Eiji Ikenaga, Masaaki Kobata, Keisuke Kobayashi, Yoshihiko Takano, Masanori Nagao, Tomohiro Takenouchi, Hiroshi Kawarada, Tamio Oguchi

    NEW DIAMOND AND FRONTIER CARBON TECHNOLOGY 17 (1) 11-19 2007年

    出版者・発行元:MYU K K

    ISSN:1344-9931

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    The valence band electronic structures of heavily boron-doped superconducting diamond films made by microwave plasma-assisted chemical vapor deposition (MPCVD) were investigated by hard X-ray photoemission spectroscopy (HXPES) and soft X-ray angle-resolved photoemission spectroscopy (SXARPES). The HXPES core-level spectrum of heavily boron-doped diamond shows a new feature at the lower binding energy side of the C Is main peak. The HXPES valence band spectrum of a heavily boron-doped superconducting diamond film shows a broader spectral shape than that of a lightly doped non-superconducting sample. The SXARPES results of homoepitaxial CVD films show clear valence band dispersions with a bandwidth of similar to 23 eV and the top of the valence band at the Gamma point in the Brillouin zone, which are well explained by the calculated valence band dispersions of pure diamond. Boron con centrati on-dependent band dispersions near the Fermi level (E-F) by SXARPES exhibit a systematic shift in E-F, indicating electron depopulation due to hole doping, and an increase in the line shape corresponding to the broader density of states observed by HXPES. These results indicate that holes in the top of the valence band are responsible for the metallic states leading to superconductivity at low temperatures. The HXPES C Is core-level spectra of lightly boron-doped non-superconducting and heavily boron-doped superconducting films are also shown.

  195. Electronic structures of heavily boron-doped superconducting diamond films 査読有り

    Takayoshi Yokoya, Hiroyuki Okazaki, Tetsuya Nakamura, Tomohiro Matsushita, Takayuki Muro, Eiji Ikenaga, Masaaki Kobata, Keisuke Kobayashi, Akihisa Takeuchi, Akihiro Awaji, Yoshihiko Takano, Masanori Nagao, Tomohiro Takenouchi, Hiroshi Kawarada, Tamio Oguchi

    DIAMOND ELECTRONICS - FUNDAMENTALS TO APPLICATIONS 956 39-+ 2007年

    出版者・発行元:MATERIALS RESEARCH SOC

    ISSN:0272-9172

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    Recent photoemission studies on heavily boron-doped superconducting diamond films, reporting the electronic structure evolution as a function of boron concentrations, are reviewed. From soft X-ray angle-resolved photoemission spectroscopy, which directly measures electronic band dispersions, depopulation of electrons (or formation of hole pockets) at the top of the valence band were clearly observed. This indicates that the holes at the top of the valence bands are responsible for the metallic properties and hence superconductivity at lower temperatures. Hard X-ray photoemission spectroscopy observed shift of the main C Is core level and intensity evolution of a lower binding energy additional structure, suggesting chemical potential shift, carrier doping efficiency by boron doping, and possibility of boron-related cluster formations.

  196. Soft x-ray magnetic circular dichroism of Ce(Fe0.8Co0.2)(2)

    M. Tsunekawa, S. Imada, A. Matsumoto, A. Yamasaki, H. Fujiwara, S. Suga, B. Schmid, H. Higashimichi, T. Nakamura, T. Muro, H. Wada

    SYNCHROTRON RADIATION INSTRUMENTATION, PTS 1 AND 2 879 1703-+ 2007年

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.2436397  

    ISSN:0094-243X

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    Soft x-ray magnetic circular dichroism study was performed at the L-2,L-3 edges of iron and cobalt and the M-4,M-5 edge of cerium in the ferromagnetic Ce(Fe0.8Co0.2)(2) compound. The spin and orbital angular magnetic moments of Fe and Co were separately estimated by applying the sum-rules to the magnetic circular dichroism spectra. The estimated magnetic moment of Co is much smaller than that of Fe, suggesting that the small magnetic moment of Co is associated with the suppression of the magnetization in this system. We have also estimated the Ce 4f electron number from the absorption spectrum.

  197. High-order Dy multipole motifs observed in DyB2C2 with resonant soft x-ray Bragg diffraction 査読有り

    A. M. Mulders, U. Staub, V. Scagnoli, S. W. Lovesey, E. Balcar, T. Nakamura, A. Kikkawa, G. van der Laan, J. M. Tonnerre

    JOURNAL OF PHYSICS-CONDENSED MATTER 18 (49) 11195-11202 2006年12月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0953-8984/18/46/012  

    ISSN:0953-8984

    eISSN:1361-648X

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    Resonant soft x-ray Bragg diffraction at the DyM4,5 edges has been exploited to study Dy multipole motifs in DyB2C2. Our results are explained by introducing the intra-atomic quadrupolar interaction between the core 3d and valence 4f shell. This allows us to determine for the first time higher-order multipole moments of dysprosium 4f electrons and to draw their precise charge density. The Dy hexadecapole and hexacontatetrapole moment have been estimated at -20% and +30% of the quadrupolar moment, respectively. No evidence for the lock-in of the orbitals at T-N has been observed, in contrast to earlier suggestions. The multipolar interaction and the structural transition cooperate along c but they compete in the basal plane, explaining the canted structure along [110].

  198. X-ray magnetic circular dichroism studies of (001)-oriented NiFe∕Mn100−xPtx exchange bilayers 査読有り

    YamatoT, KumeT, KatoT, TsunashimaS, NakamuraT, FujiwaraY, IwataS

    Journal of Applied Physics 100 (11) 113907 2006年12月

    出版者・発行元:None

    DOI: 10.1063/1.2388136  

    ISSN:0021-8979

  199. Soft x-ray magnetic circular dichroism study of Mn–Ir∕Co–Fe bilayers with giant exchange anisotropy 査読有り

    TsunodaM, NakamuraT, NakaM, YoshitakiS, MitsumataC, TakahashiM

    Applied Physics Letters 89 (17) 172501 2006年10月

    出版者・発行元:None

    DOI: 10.1063/1.2364116  

    ISSN:0003-6951

  200. Orbital order in DyB2C2 studied with resonant soft X-ray scattering 査読有り

    A. M. Mulders, U. Staub, V. Scagnoli, T. Nakamura, A. Kikkawa, J. M. Tonnerre

    PHYSICA B-CONDENSED MATTER 378-80 367-368 2006年5月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.physb.2006.01.129  

    ISSN:0921-4526

    eISSN:1873-2135

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    Resonant soft X-ray scattering at the Dy M-4.5 edges has been used to study orbital order in DyB2C2. The charge forbidden (00 11) Bragg reflection appears below the antiferroquadrupolar ordering temperature, and its temperature dependence is studied through the lower lying magnetic ordering temperature T-N. The energy dependence of the resonant (00 1) reflection indicates more than one scattering component. In contrast to earlier suggestions, no evidence for the lock-in of the orbitals is observed at TN. (c) 2006 Elsevier B.V. All rights reserved.

  201. Direct observation of ferromagnetic spin polarization in gold nanoparticles (vol 93, pg 116801, 2004)

    Y Yamamoto, T Miura, T Teranishi, H Hori, M Suzuki, N Kawamura, H Miyagawa, T Nakamura, K Kobayashi

    PHYSICAL REVIEW LETTERS 96 (13) 2006年4月

    出版者・発行元:AMERICAN PHYSICAL SOC

    DOI: 10.1103/PhysRevLett.96.139902  

    ISSN:0031-9007

  202. MCD Study on CexLa1-xNi: Difference between the “Local” and “Coherent” Kondo Effect 査読有り

    Satoshi Nakamura, Testuo Yoshida, Yasuhiro Takayama, Tsuneaki Miyahara, Hiroyoshi Ishii, Hitoshi Sugawara, Hideyuki Sato, Tetsuya Nakamura

    Journal of the Physical Society of Japan 75 (4) 044707 2006年4月

    出版者・発行元:Physical Society of Japan

    DOI: 10.1143/JPSJ.75.044707  

    ISSN:0031-9015

  203. Hard X-ray photoelectron emission microscopy as tool for studying buried layers 査読有り

    T Wakita, T Taniuchi, K Ono, M Suzuki, N Kawamura, M Takagaki, H Miyagawa, FZ Guo, T Nakamura, T Muro, H Akinaga, T Yokoya, M Oshima, K Kobayashi

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS 45 (3A) 1886-1888 2006年3月

    出版者・発行元:JAPAN SOC APPLIED PHYSICS

    DOI: 10.1143/JJAP.45.1886  

    ISSN:0021-4922

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    We have performed photoelectron emission microscopy measurements with hard X-rays (HX-PEEM) and have shown that HX-PEEM has a spatial resolution higher than 106 nm for observing the sample surface and can detect signals from a Au layer buried under a 50-nm-thick Co layer. These results mean that HX-PEEM has a probing depth one order of magnitude deeper than that of PEEM with soft X-rays. This deeper probing depth with HX-PEEM provides a new opportunity to investigate electronic and/or magnetic structures of buried layers under a thick overlayer. The notable advantages and potential applications of HX-PEEM are discussed.

  204. STM/STS study on 4ax4a electronic charge modulation of Bi2Sr2CaCu2O8+delta 査読有り

    A. Hashimoto, Y. Kobatake, S. Nakamura, N. Momono, M. Oda, M. Ido

    LOW TEMPERATURE PHYSICS, PTS A AND B 850 521-+ 2006年

    出版者・発行元:AMER INST PHYSICS

    ISSN:0094-243X

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    We performed low-bias STM measurements on lightly doped Bi2212 crystals, and confirmed the development of two-dimensional (2D) superstructure with a periodicity of four lattice constants (4a) within the Cu-O layer at T &lt; T-c. This 4a x 4a superstructure orients along the Cu-0 bonding direction, and is nondispersive. The nondispersive 4a x 4a superstructure was clearly observed within the ZTPG or d-wave gap, while it tended to fade out outside the gaps.

  205. XMCD study of Mn-Ir/Co-Fe bilayers with giant exchange anisotropy 査読有り

    M. Tsunoda, T. Nakamura, M. Naka, S. Yoshitaki, C. Mitsumata, M. Takahashi

    INTERMAG 2006 - IEEE International Magnetics Conference 410 2006年

    DOI: 10.1109/INTMAG.2006.376134  

  206. XMCD studies of epitaxially grown Mn1-xPtx / Ferromagnet exchange bilayers with (001) orientation 査読有り

    T. Kato, T. Yamato, T. Kume, T. Nakamura, Y. Fujiwara, S. Iwata, S. Tsunashima

    INTERMAG 2006 - IEEE International Magnetics Conference 960 2006年

    DOI: 10.1109/INTMAG.2006.374991  

  207. Soft X-ray angle-resolved photoemission spectroscopy of heavily boron-doped superconducting diamond films 査読有り

    T. Yokoya, T. Nakamura, T. Matushita, T. Muro, H. Okazaki, M. Arita, K. Shimada, H. Namatame, M. Taniguchi, Y. Takano, M. Nagao, T. Takenouchi, H. Kawarada, T. Oguchi

    SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 7 (sup1) S12-S16 2006年

    出版者・発行元:NATL INST MATERIALS SCIENCE

    DOI: 10.1016/j.stam.2006.02.014  

    ISSN:1468-6996

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    We have performed soft X-ray angle-resolved photoemission spectroscopy (SXARPES) of microwave plasma-assisted chemical vapor deposition diamond films with different B concentrations in order to study the origin of the metallic behavior of superconducting diamond. SXARPES results clearly show valence band dispersions with a bandwidth of similar to 23 eV and with a top of the valence band at gamma point in the Brillouin zone, which are consistent with the calculated valence band dispersions of pure diamond. Boron concentration-dependent band dispersions near the Fermi level (E-F) exhibit a systematic shift of E-F, indicating depopulation of electrons due to hole doping. These SXARPES results indicate that diamond bands retain for heavy boron doping and holes in the diamond band are responsible for the metallic states leading to superconductivity at low temperature. A high-resolution photoemission spectroscopy spectrum near E-F of a heavily boron-doped diamond superconductor is also presented. (c) 2006 NIMS and Elsevier Ltd. All rights reserved.

  208. Interface effects on the magnetic moment of Co and Cu in CoCu granular alloys 査読有り

    A. García Prieto, M. L. Fdez-Gubieda, J. Chaboy, M. A. Laguna-Marco, T. Muro, T. Nakamura

    Physical Review B - Condensed Matter and Materials Physics 72 (21) 2005年12月1日

    DOI: 10.1103/PhysRevB.72.212403  

    ISSN:1098-0121 1550-235X

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    We report on x-ray magnetic circular dichroism experiments performed on Co5Cu95 annealed granular alloys with giant magnetoresistance. Results on the Co-L2,3 edge evidence a direct correlation between the Co orbital and spin magnetic moment and the Co clusters interfacial roughness. On the other hand, we have found dichroism on the Cu-L2,3 edge, revealing an induced magnetic polarization of the Cu interfacial atoms. The magnetic moment of the Cu atoms is mainly of spin character and is ferromagnetically coupled with the Co magnetic moment. © 2005 The American Physical Society.

  209. Origin of the metallic properties of heavily boron-doped superconducting diamond 査読有り

    T Yokoya, T Nakamura, T Matsushita, T Muro, Y Takano, M Nagao, T Takenouchi, H Kawarada, T Oguchi

    NATURE 438 (7068) 647-650 2005年12月

    出版者・発行元:NATURE PUBLISHING GROUP

    DOI: 10.1038/nature04278  

    ISSN:0028-0836

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    The physical properties of lightly doped semiconductors are well described by electronic band- structure calculations and impurity energy levels(1). Such properties form the basis of present- day semiconductor technology. If the doping concentration n exceeds a critical value n(c), the system passes through an insulator- to- metal transition and exhibits metallic behaviour; this is widely accepted to occur as a consequence of the impurity levels merging to form energy bands(2). However, the electronic structure of semiconductors doped beyond nc have not been explored in detail. Therefore, the recent observation of superconductivity emerging near the insulator- to- metal transition(3) in heavily boron- doped diamond(4,5) has stimulated a discussion on the fundamental origin of the metallic states responsible for the superconductivity. Two approaches have been adopted for describing this metallic state: the introduction of charge carriers into either the impurity bands(6) or the intrinsic diamond bands(7-9). Here we show experimentally that the doping- dependent occupied electronic structures are consistent with the diamond bands, indicating that holes in the diamond bands play an essential part in determining the metallic nature of the heavily boron- doped diamond superconductor. This supports the diamond band approach and related predictions, including the possibility of achieving dopant- induced superconductivity in silicon and germanium(7). It should also provide a foundation for the possible development of diamond- based devices(10).

  210. -Interface effects on the magnetic moment of Co and Cu in CoCu granular alloys 査読有り

    AG Prieto, ML Fdez-Gubieda, J Chaboy, MA Laguna-Marco, T Muro, T Nakamura

    PHYSICAL REVIEW B 72 (21) 212403 2005年12月

    出版者・発行元:AMER PHYSICAL SOC

    DOI: 10.1103/PhysRevB.72.212403  

    ISSN:2469-9950

    eISSN:2469-9969

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    We report on x-ray magnetic circular dichroism experiments performed on Co5Cu95 annealed granular alloys with giant magnetoresistance. Results on the Co-L-2,L-3 edge evidence a direct correlation between the Co orbital and spin magnetic moment and the Co clusters interfacial roughness. On the other hand, we have found dichroism on the Cu-L-2,L-3 edge, revealing an induced magnetic polarization of the Cu interfacial atoms. The magnetic moment of the Cu atoms is mainly of spin character and is ferromagnetically coupled with the Co magnetic moment.

  211. Control of ferroelectric phase by chemical pressure in (Gd, Tb)MnO3 crystals

    K Noda, S Nakamura, H Kuwahara

    IEEE TRANSACTIONS ON MAGNETICS 41 (10) 2814-2816 2005年10月

    出版者・発行元:IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    DOI: 10.1109/TMAG.2005.854835  

    ISSN:0018-9464

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    We have investigated the dielectric properties of Gd1-xTbxMnO3 crystals in magnetic fields to clarify the crossover between two distinct ferroelectric phases, GdMnO3 -type (first-order displacive) and TbMnO3 -type (second-order order-disorder). We have found that the compositional phase boundary between the phases exists around 0. 3 &lt; x &lt; 0.4. For the x = 0. 1 sample exposed to magnetic fields above 3 T, we have discovered successive ferroelectric phase transitions that occur at two different temperatures. We have determined the electric and magnetic phase diagram for x = 0, 0.1, and 0.3 in the plane of temperature and field in order to demonstrate the change in the ferroelectric phases.

  212. Influence of the interface on the magnetic moment of Co clusters in CoCu granular alloys 査読有り

    AG Prieto, ML Fdez-Gubieda, J Chaboy, MA Laguna-Marco, T Muro, T Nakamura

    IEEE TRANSACTIONS ON MAGNETICS 41 (10) 3421-3423 2005年10月

    出版者・発行元:IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC

    ISSN:0018-9464

    eISSN:1941-0069

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    We report on X-ray magnetic circular dichroism experiments performed on Co5Cu95 as-quenched and annealed granular alloys with giant magnetoresistance (GMR). Results of the, Co-L-2,L-3 edges give evidence of a direct correlation between the Co orbital and spin magnetic moment with the Co clusters interfacial roughness, a matter that is critical in the GMR response.

  213. Soft X-ray magnetic circular dichroism study of Al40Mn25Fe15Ge20 decagonal quasicrystal 査読有り

    T Nakamura, Y Yokoyama, N Kamakura, T Matsushita, T Hirono, T Muro, K Kobayashi

    NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS 238 (1-4) 251-254 2005年8月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.nimb.2005.06.057  

    ISSN:0168-583X

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    Magnetic properties of a spin-glass Al40Mn25Fe15Ge20 decagonal quasicrystal (QC) have been studied by means of soft X-ray magnetic circular dichroism (MCD). Element specific magnetic hysteresis (ESMH) loops have been measured as magnetic field dependence of MCD intensity at the Mn and Fe L-3-edges. A significant difference has been found in the ESMH loops between Mn and Fe in the QC, where only the Mn loop has an obvious remanent-like magnetization. This result of ESMH has suggested that Mn and Fe magnetic moments have different magnetic viscosities in the spin-glass QC. A ferromagnetic approximant-crystalline Al40Mn40Ge20 has also been investigated in comparison with the QC. (c) 2005 Elsevier B.V. All rights reserved.

  214. The giant magneto-volume effect in solid oxygen 査読有り

    K Katsumata, S Kimura, U Staub, Y Narumi, Y Tanaka, S Shimomura, T Nakamura, SW Lovesey, T Ishikawa, H Kitamura

    JOURNAL OF PHYSICS-CONDENSED MATTER 17 (23) L235-L239 2005年6月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0953-8984/17/23/L03  

    ISSN:0953-8984

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    X-ray diffraction measurements on a-solid oxygen under an applied magnetic field are reported. The volume of alpha-solid O-2 is found to expand with increasing magnetic field: the lattice constants a and b elongate, while the lattice constant c and the angle are almost independent of the magnetic field. The maximum volume expansion observed is about 1% under a 7.5 T field, which is a giant effect compared to the volume change observed in ferromagnetic metals, such as Fe, Co and Ni. This finding indicates that a spin-dependent intermolecular potential is essential in determining the structure of alpha-solid O-2. The experimental results conform with predictions based on a magneto-elastic interaction derived from an antiferromagnetic exchange coupling of O-2 spins.

  215. Development of a soft X-ray magnetic circular dichroism spectrometer using a 1.9T electromagnet at BL25SU of SPring-8 査読有り

    T Nakamura, T Muro, FZ Guo, T Matsushita, T Wakita, T Hirono, Y Takeuchi, K Kobayashi

    JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA 144 1035-1038 2005年6月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.elspec.2005.01.146  

    ISSN:0368-2048

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    A soft X-ray magnetic circular dichroism (SXMCD) spectrometer system using a water-cooled electromagnet of 1.9 T has been installed at BL25SU of SPring-8. The purpose is to develop an optimized system for element specific magnetization (ESM) measurements by means of SXMCD. A combination between the variable magnetic field and the helicity switching technique using the twin helical undulators gives a great advantage for measuring precise ESM loops. The present system is especially useful for investigations of magnetic properties on multi-layered thin films and ultra-thin films in addition to multi-elements alloys and compounds. (c) 2005 Elsevier B.V. All rights reserved.

  216. Circular dichroism measurement of soft X-ray absorption using helicity modulation of helical undulator radiation 査読有り

    T Muro, T Nakamura, T Matsushita, H Kimura, T Nakatani, T Hirono, T Kudo, K Kobayashi, Y Saitoh, M Takeuchi, T Hara, K Shirasawa, H Kitamura

    JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA 144 1101-1103 2005年6月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.elspec.2005.01.140  

    ISSN:0368-2048

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    The measurement of circular dichroism (CD) in soft X-ray absorption at BL25SU of SPring-8 has been developed into a phase-sensitive detection using helicity modulation (HM) of circularly polarized light. The HM is performed by the light source, "twin helical undulators". A lock-in amplifier is used for the phase-sensitive detection to extract small CD signals buried in noises. The noise level of a measured magnetic CD has been reduced to less than 1/10 by using this method in comparison with a normal integration measurement. (c) 2005 Elsevier B.V. All rights reserved.

  217. Electronic and magnetic structures of Fe on a vicinal Au(111) surface 査読有り

    H Fujisawa, S Shiraki, M Furukawa, M Nantoh, M Kawai, T Nakamura, T Muro

    JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA 144 519-523 2005年6月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.elspec.2005.01.021  

    ISSN:0368-2048

    eISSN:1873-2526

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    Magnetic behavior of Fe nanostructures on a vicinal Au(111) surface have been investigated by X-ray magnetic circular dichroism (XMCD) measurements. It is found that one-dimensional (1D) Fe chains of 2-3 atomic rows exhibit a ferromagnetic long-range order, and have a larger orbital moment in comparison with stripes and two-dimensional (2D) nanostructures. From the temperature-dependent XMCD measurements, the 1D chains exhibit two phase transitions, which are qualitatively ascribed to a ferromagnetic-to-superparamagnetic and a superparamagnetic-to-paramagnetic phase transions. These results suggest that the magnetism of the 1D chains behaves superparamagnetically. (c) 2005 Elsevier B.V. All rights reserved.

  218. Magnetic field and external-pressure effect on ferroelectricity in manganites: Comparison between GdMnO3 and TbMnO3

    K Noda, S Nakamura, J Nagayama, H Kuwahara

    JOURNAL OF APPLIED PHYSICS 97 (10) 10C103-1-10C103-3 2005年5月

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.1851420  

    ISSN:0021-8979

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    We have investigated dielectric properties in Mott insulators GdMnO3 and TbMnO3 under magnetic fields and external quasihydrostatic pressures. In the case of GdMnO3, thermal hysteresis for dielectric constant s and discontinuous lattice distortion were observed at ferroelectric transition temperature (T-C), and ferroelectric spontaneous polarization was suppressed by the application of external pressure. These results indicate that the ferroelectric transition in GdMnO3 is a first-order displacive-type one. On the other hand, the thermal hysteresis and discontinuous lattice striction were not observed at T-C in TbMnO3. The peak of E corresponding to the ferroelectric transition was shifted toward higher temperatures by the application of external pressure in TbMnO3. The ferroelectric transition of TbMnO3 was thought to be a second-order order-disorder-type one. (c) 2005 American Institute of Physics.

  219. Magnetic field and external pressure control of ferro electricity in multiferroic manganites

    H Kuwahara, K Noda, J Nagayama, S Nakamura

    PHYSICA B-CONDENSED MATTER 359 1279-1281 2005年4月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.physb.2005.01.356  

    ISSN:0921-4526

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    We have investigated dielectric properties in a series of crystals of RMnO3 (R is a rare-earth ion) under magnetic fields and quasihydrostatic pressure. We have found that a ferroelectric phase appeared in GdMnO3 crystal below 13 K. We have confirmed that a small spontaneous polarization exists along a-axis (P-a) in the orthorhombic Pbnm setting and that P-a can be reversed by the DC electric field. The dielectric anomaly due to the ferroelectric transition accompanied thermal hysteresis and lattice striction. The ferroelectric transition temperature decreased with quasi hydrostatic pressure. These results indicate that the ferroelectric transition is improper and is of the first-order displacement type. P-a was easily collapsed by the application of a magnetic field of 0.4 T parallel to the spin-canting direction (H parallel to c) while it was enhanced parallel to the easy axis (H parallel to b). (c) 2005 Elsevier B.V. All rights reserved.

  220. Lifetime-broadening-removed XANES spectroscopy by high-resolution resonant inelastic x-ray scattering 査読有り

    H. Hayashi, R. Takeda, Y. Udagawa, T. Nakamura, H. Miyagawa, H. Shoji, S. Nanao, N. Kawamura

    Physica Scripta T T115 1094-1096 2005年

    DOI: 10.1238/Physica.Topical.115a01094  

    ISSN:0281-1847

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    Resonant inelastic x-ray scattering (RIXS) is uniquely related to x-ray absorption oscillator strength distribution by Kramers-Heisenberg equation via lifetime widths of the states involved. By using RIXS spectra of CuO it is shown that XANES, where the lifetime broadening (LB) of the 1s core-hole is removed and that of the 2p hole determines the resolution, can be analytically deduced from RIXS profiles. Furthermore, it is demonstrated that numerical procedures can eliminate also the remaining 2p broadening, providing LB-free XANES. © Physica Scripta 2005.

  221. Orbital dynamics of the 4f shell in DyB2C2 査読有り

    U Staub, AM Mulders, O Zaharko, S Janssen, T Nakamura, SW Lovesey

    PHYSICAL REVIEW LETTERS 94 (3) 036408 2005年1月

    出版者・発行元:AMERICAN PHYSICAL SOC

    DOI: 10.1103/PhysRevLett.94.036408  

    ISSN:0031-9007

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    For the first time, fluctuations in the Dy quadrupole (orbital) moment have been observed in DyB2C2 using inelastic neutron scattering. The observed quasielastic response is decomposed into two components, one reflecting transitions within the doublets (narrow) and the other transitions between the doublets (broad) of the effective Dy quartet ground state. The widths of the narrow and broad components are shown to arise from fluctuations in the magnetic dipole and the electric quadrupole moments, respectively.

  222. Soft X-ray magnetic circular dichroism of Cr-doped GaN 査読有り

    H. Makino, J. J. Kim, T. Nakamura, T. Muro, K. Kobayashi, T. Yao

    Current Applied Physics 4 (6) 615-617 2004年11月

    DOI: 10.1016/j.cap.2004.01.031  

    ISSN:1567-1739

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    Soft X-ray magnetic circular dichroism (XMCD) have been measured for the Ga0.97Cr0.03N film grown by NH3-assisted molecular beam epitaxy. Temperature dependence of the XMCD intensity was well described by the Curie-Weiss law. Although the sample showed ferromagnetic behavior at least up to room temperature, the ferromagnetic component could not be detected by the XMCD measurement. © 2004 Elsevier B.V. All rights reserved.

  223. Synchrotron X-ray Diffraction Studies of the Incommensurate Phase of a Spin–Peierls System CuGeO3in Strong Magnetic Fields 査読有り

    Yasuo Narumi, Koichi Katsumata, Yoshikazu Tabata, Shojiro Kimura, Yoshikazu Tanaka, Tetsuya Nakamura, Susumu Shimomura, Masaaki Matsuda, Isao Harada, Yoshihiro Nishiyama, Tetsuya Ishikawa, Hideo Kitamura, Toru Hara, Takashi Tanaka, Kenji Tamasaku, Makina Yabashi, Shunji Goto, Haruhiko Ohashi, Kunikazu Takeshita, Toru Ohata, Tomohiro Matsushita, Teruhiko Bizen

    Journal of the Physical Society of Japan 73 (10) 2650-2653 2004年10月

    出版者・発行元:Physical Society of Japan

    DOI: 10.1143/JPSJ.73.2650  

    ISSN:0031-9015

  224. Direct observation of ferromagnetic spin polarization in gold nanoparticles 査読有り

    Y Yamamoto, T Miura, M Suzuki, N Kawamura, H Miyagawa, T Nakamura, K Kobayashi, T Teranishi, H Hori

    PHYSICAL REVIEW LETTERS 93 (11) 116801 2004年9月

    出版者・発行元:AMERICAN PHYSICAL SOC

    DOI: 10.1103/PhysRevLett.93.116801  

    ISSN:0031-9007

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    We report the first direct observation of ferromagnetic spin polarization of Au nanoparticles with a mean diameter of 1.9 nm using x-ray magnetic circular dichroism (XMCD). Owing to the element selectivity of XMCD, only the gold magnetization is explored. Magnetization of gold atoms as estimated by XMCD shows a good agreement with results obtained by conventional magnetometry. This evidences intrinsic spin polarization in nanosized gold.

  225. Quadrupolar, structural, and magnetic ordering in DyB2C2 studied by symmetry analysis and neutron diffraction 査読有り

    O Zaharko, W Sikora, F Bialas, U Staub, T Nakamura

    PHYSICAL REVIEW B 69 (22) 224417 2004年6月

    出版者・発行元:AMERICAN PHYSICAL SOC

    DOI: 10.1103/PhysRevB.69.224417  

    ISSN:1098-0121

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    Antiferroquadrupolar (AFQ) and antiferromagnetic (AFM) order in DyB2C2 have been investigated by theoretical symmetry analysis and neutron single crystal diffraction experiment with 0 to 4 T applied magnetic field along [100]. New symmetry arguments indicate that the AFQ ordering below T-Q=24.7 K is accompanied by structural distortions involving boron and carbon atoms, but not dysprosium ions. In the AFQ phase a new arrangement of quadrupoles is proposed based on symmetry analysis of the long-range quadrupolar ordering, neutron diffraction study of the field-induced dipolar magnetic structure, and other available observations. This is a 90degrees arrangement of quadrupoles of neighboring atoms in the xy plane, and along z. For the zero-field AFM phase, the refinement of neutron single crystal diffraction data of (DyB2C2)-B-11 against models proposed by Yamauchi [J. Phys. Soc. Jpn. 68, 2057 (1999) ] (model A) and by van Duijn, Attfield, and Suzuki [Phys. Rev. B 62, 6410 (2000) ] (model B) allows to give preference to modified model A. The magnetic moments of the four Dy sublattices are equal and are confined in the xy plane. The tilt of the Dy moments from the x axis is 36(4)degrees at (0 0 0) and -112(4)degrees at the (1/2 1/2 0) site. The angle between the Dy moments adjacent along z is 76(6)degrees and not 90degrees as proposed originally.

  226. X-ray magnetic circular dichroism study of gold nanoparticles protected by polymer 査読有り

    Y. Yamamoto, T. Miura, T. Teranishi, M. Suzuki, N. Kawamura, H. Miyagawa, T. Nakamura, K. Kobayashi, H. Hori

    Journal of Magnetism and Magnetic Materials 272-276 (1) e1183-e1184 2004年5月

    DOI: 10.1016/j.jmmm.2003.12.620  

    ISSN:0304-8853

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    Bulk Au metal is chemically stable and has diamagnetic properties. However, these properties might be different in nano-sized region. This article reports that the direct observation of spontaneous spin polarization of Au nanoparticles employing X-ray magnetic circular dichroism (XMCD). Magnetization estimated by XMCD shows a good agreement with the results obtained by DC magnetization. This result evidences the intrinsic spin polarization in nano-sized material. © 2003 Elsevier B.V. All rights reserved.

  227. Synchrotron X-ray diffraction studies on magnetic materials in high magnetic fields 査読有り

    Y Narumi, K Katsumata, Y Tanaka, T Nakamura, S Shimomura, Y Tabata, S Kimura, M Matsuda

    PHYSICA B-CONDENSED MATTER 346 11-14 2004年4月

    出版者・発行元:ELSEVIER SCIENCE BV

    DOI: 10.1016/j.physb.2004.01.011  

    ISSN:0921-4526

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    Non-resonant X-ray diffraction measurements on two kinds of magnetic materials were performed at the BL19LXU on SPring-8 in high magnetic fields. Magnetic reflections were observed in the metamagnet FeCl2 . 2H(2)O in the antiferromagnetic (AF) and the field-induced intermediate (1) phases. The field dependence of these reflections evidences a coexistence of the AF and I phases in a wide region of magnetic field when the field is decreased from the I phase. The lattice modulations in the field-induced magnetic phase of the spin-Peierls compound CuGeO3 were studied. The field dependence of the incommensurability measured up to 15 T is reproduced by the theory developed by Buzdin et al. (C) 2003 Elsevier B.V. All rights reserved.

  228. The coexistence of magnetic phases at the first-order phase transition of a metamagnet FeCl 2 ·2H 2 O studied by x-ray diffraction 査読有り

    Y Narumi, K Katsumata, T Nakamura, Y Tanaka, S Shimomura, T Ishikawa, M Yabashi

    Journal of Physics: Condensed Matter 16 (7) L57-L63 2004年2月

    出版者・発行元:None

    DOI: 10.1088/0953-8984/16/7/L02  

    ISSN:0953-8984

  229. A Measurement System For Circular Dichroism In Soft X‐ray Absorption Using Helicity Switching By Twin Helical Undulators 査読有り

    MuroT, SaitohY, KimuraH, MatsushitaT, NakataniT, TakeuchiM, HironoT, KudoT, NakamuraT, WakitaT, KobayashiK, HaraT, ShirasawaK, KitamuraH

    AIP Conference Proceedings 705 (1) 1051-1054 2004年

    出版者・発行元:None

    DOI: 10.1063/1.1757978  

    ISSN:0094-243X

  230. Quadrupole and hexadecapole ordering in DyB2C2: Direct observation with resonant x-ray diffraction 査読有り

    Y Tanaka, T Inami, SW Lovesey, KS Knight, F Yakhou, D Mannix, J Kokubun, M Kanazawa, K Ishida, S Nanao, T Nakamura, H Yamauchi, H Onodera, K Ohoyama, Y Yamaguchi

    PHYSICAL REVIEW B 69 (2) 024417 2004年1月

    出版者・発行元:AMERICAN PHYSICAL SOC

    DOI: 10.1103/PhysRevB.69.024417  

    ISSN:1098-0121

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    Direct evidence of the spatial ordering of Dy 4f quadrupole and hexadecapole moments in DyB2C2 is demonstrated by resonant x-ray diffraction enhanced by an electric quadrupole event (E2 resonance) at the Dy L-III absorption edge. The diffraction data show that the structural phase transition at T-Q=24.7 K is accompanied by a reduction in the symmetry of the Dy site to 2/m, from 4/m, and the spatial ordering of the time-even Dy multipoles with A(g) character. Below T-Q the crystal structure is described by the space group P4(2)/mnm and Dy ions occupy sites (4c). The distortion at T-Q involves the lattice occupied by B and C ions, and it amounts to a buckling of B-C planes that are normal to the two-fold rotation axis of 2/m. An immediately plausible model of low-energy Dy states correlates data on the specific heat, our x-ray diffraction signals, and magnetic ordering below 15.3 K which has been observed in magnetic neutron diffraction.

  231. Lifetime-broadening-suppressed/free XANES spectroscopy by high-resolution resonant inelastic x-ray scattering 査読有り

    Hisashi Hayashi, Rumi Takeda, Yasuo Udagawa, Tetsuya Nakamura, Hayato Miyagawa, Hironobu Shoji, Susumu Nanao, Naomi Kawamura

    Physical Review B - Condensed Matter and Materials Physics 68 (4) 2003年7月15日

    DOI: 10.1103/PhysRevB.68.045122  

    ISSN:1550-235X 1098-0121

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    The resonant inelastic x-ray scattering (RIXS) spectrum is uniquely related to the x-ray absorption oscillator strength distribution by the Kramers-Heisenberg equation via lifetime widths of the states involved. In this work it is shown that x-ray absorption near-edge structure (XANES), where the lifetime broadening of 1s core holes is suppressed and that of the 2p hole determines the resolution, can be analytically deduced from RIXS spectra. Furthermore, it is demonstrated that numerical procedures can provide lifetime-broadening-free (LBF) XANES, where the remaining 2p broadening is also eliminated. As examples, lifetime-broadening-suppressed (LBS) XANES and LBF-XANES of CuO and CuCl2⋅2H2O are derived from RIXS spectra measured by the use of a third-generation synchrotron source SPring-8 and are compared with XANES obtained by other methods to discuss the significance of LBS and LBF XANES spectroscopy. © 2003 The American Physical Society.

  232. Crystal-field levels in pure and diluted DyB2C2 studied by neutron inelastic scattering technique 査読有り

    T Nakamura, U Staub, Y Narumi, K Katsumata, F Juranyi

    EUROPHYSICS LETTERS 62 (2) 251-256 2003年4月

    出版者・発行元:EDP SCIENCES S A

    DOI: 10.1209/epl/i2003-00353-8  

    ISSN:0295-5075

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    Inelastic neutron scattering experiments on (DyB2C2)-B-11 and (Dy0.07Y0.93B2C2)-B-11 have been performed. The results enable us to infer important properties of the crystal-field levels of Dy3+ in DyB2C2 which has fascinating structural and magnetic properties that are attributed to the electronic states of the Dy ion. While no clear excitation was observed in pure DyB2C2, three excitations from the ground state with the energies 1.4, 4.1 and 5.8 meV were observed in (Dy0.07Y0.93B2C2)-B-11. By comparing the present results with the previous crystal-field calculation, we infer that the ground state of Dy3+ in YB2C2 is Gamma(8) which is split into two Kramers doublets by the tetragonal potential. Additionally, the heat capacity measured on the diluted system is compared with a calculation using the low part of the energy level scheme obtained from the neutron experiments. Good agreement between theory and experiment is obtained.

  233. Magnetic circular dichroism of resonant x-ray emission spectroscopy for Sm L3M4,5 and L2M4 in a Sm21Co79 amorphous alloy 査読有り

    T Nakamura, H Shoji, E Hirai, S Nanao, K Fukui, H Ogasawara, A Kotani, T Iwazumi, Harada, I, R Katano, Y Isozumi

    PHYSICAL REVIEW B 67 (9) 2003年3月

    出版者・発行元:AMER PHYSICAL SOC

    DOI: 10.1103/PhysRevB.67.094439  

    ISSN:1098-0121

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    The magnetic circular dichroism (MCD) of resonant x-ray emission spectroscopy (RXES) was studied for the Sm L3M4,5 and L2M4 optical processes in a ferromagnetic Sm21Co79 amorphous alloy. The MCD of RXES (MCDRXES) originating from the optical process of 2p(6)3d(10)4f(n)--&gt;2p(5)3d(10)4f(n+1)--&gt;2p(6)3d(9)4f(n+1), which corresponds to dipolar decay after quadrupolar (E2) excitation, was obviously observed at the preedge region in addition to that of the normal dipolar (E1) excitation. Moreover, the E2 contribution of the MCD has been separated into those for E2 excitation to the Sm 4f state with majority and minority spins. A theoretical calculation based on a formula of the coherent second-order optical process was carried out for all of the experimental MCDRXES spectra. In the calculation, the multiplet coupling effect and the enhancement of the 2p-5d dipole matrix elements proposed for the MCD of x-ray absorption were taken into account. The calculated MCDRXES spectra reproduced all of the experimental results very successfully. The present result provided an appropriate interpretation of the origins of the MCD effect, which comes from the E1 and the E2 contributions at both the L-3 and the L-2 edges.

  234. Thermal phase transition of RbMnFe(CN)(6) observed by X-ray emission and absorption spectroscopy 査読有り

    H Osawa, T Iwazumi, H Tokoro, S Ohkoshi, K Hashimoto, H Shoji, E Hirai, T Nakamura, S Nanao, Y Isozumi

    SOLID STATE COMMUNICATIONS 125 (5) 237-241 2003年2月

    出版者・発行元:PERGAMON-ELSEVIER SCIENCE LTD

    DOI: 10.1016/S0038-1098(02)00805-0  

    ISSN:0038-1098

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    The thermal phase transition of RbMnFe(CN)(6) has been observed by Mn and Fe 3p-1s X-ray emission spectroscopy (XES) and Is X-ray absorption spectroscopy (XAS). The thermal variations of the spin states and the valences of Mn and Fe were determined to be Mn2+(S = 5/2)-NC-Fe3+(S = 1/2) for the high-temperature (HT) phase and Mn3+(S = 2)-NC-Fe2+(S = 0) for the low-temperature (LT) phase. These transitions are thus caused by charge transfer between Mn and Fe. The temperature dependences of Mn and Fe 3p-1s XES and 1s XAS were observed as the composition of the spectra of the HT and LT phases. The ratios of the HT component in each spectrum show good agreement with the thermal transition curves observed with magnetic susceptibility measurements. Published by Elsevier Science Ltd.

  235. Spin-state transitions in an iron spin-crossover complex observed with X-ray emission and X-ray absorption 査読有り

    H Osawa, T Iwazumi, H Shoji, E Hirai, T Nakamura, Y Ogawa, T Ishikawa, S Koshihara, Y Isozumi, S Nanao

    PHASE TRANSITIONS 75 (7-8) 919-925 2002年10月

    出版者・発行元:TAYLOR & FRANCIS LTD

    DOI: 10.1080/01411590290034065  

    ISSN:0141-1594

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    The thermal- and photon-induced phase transitions of [Fe(2-pic)3]Cl2EtOH from a high-spin (HS) state (S = 2) to a low-spin (LS) state (S = 0) were observed by X-ray Emission Spectroscopy (XES) and X-ray Absorption Spectroscopy (XAS). The spin state was observed with Fe 3p-1s XES from the HS and photon-induced (PI) phase took S=2 and LS state took S=0. Each spectrum of the decay process from the PI phase to the LS state could be described with the superposition of those of the HS and LS states. In XAS, a different spectrum was also observed in the HS and LS states, and likewise by XES; the difference in the pre-edge structure between the HS and LS states was explained based on the difference of Fe unoccupied 3d partial density of state calculated by the DV-Xalpha method.

  236. Orbital and spin moments in SmFe2 studied by means of white-x-ray magnetic diffraction 査読有り

    H Miyagawa, T Nakamura, Y Watanabe, M Ito, H Adachi, H Kawata, S Nanao

    JOURNAL OF PHYSICS-CONDENSED MATTER 14 (41) 9525-9534 2002年10月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0953-8984/14/41/309  

    ISSN:0953-8984

    eISSN:1361-648X

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    A magnetic structure of SmFe2 with a Laves phase crystalline structure was investigated by means of white-x-ray magnetic diffraction. The orbital and the spin magnetic form factors of Sm and Fe ions have been obtained as a function of momentum transfer. Their extrapolation to zero momentum transfer, according to the dipole approximation based on an atomic model, has given the values of the spin and the orbital magnetic moments of Sm ions as -2.54 +/- 0.55 mu(B) and 2.79 +/- 0.61 mu(B), respectively. This result confirms that the small magnetic moment of Sm ions arises from antiparallel coupling between the spin and the orbital magnetic moments.. The spin and the orbital magnetic moments of Fe ions have been also estimated, as 1.13 +/- 0.25 mu(B) and 0.19 +/- 0.04 mu(B), respectively.

  237. Observation of field-induced magnetic and structural transitions in an antiferromagnet by means of synchrotron x-rays 査読有り

    K Katsumata, Y Tabata, SW Lovesey, T Nakamura, Y Tanaka, S Shimomura, Y Narumi, T Ishikawa, H Kitamura, T Hara, T Tanaka, K Tamasaku, M Yabashi, S Goto, H Ohashi, K Takeshita, T Ohata, T Matsushita, T Bizen, Yamada, I

    JOURNAL OF PHYSICS-CONDENSED MATTER 14 (37) L619-L623 2002年9月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0953-8984/14/37/102  

    ISSN:0953-8984

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    In the first experiment of its kind, we have used x-ray diffraction to study magnetic and charge properties of an antiferromagnet as a function of an applied magnetic field H. The intensity of hard x-rays diffracted at the space-group-forbidden reflection (3,0,0) of MnF2 with H parallel to the easy axis at H=H-c/root2 shows evidence of a spin-flop transition associated with the surface magnetization, and at H-c=9.3 T a spin-flop transition in the bulk. Above H, we found intensity much larger than that predicted for purely magnetic scattering. We attribute the unexpected intensity to charge scattering created by a field-induced structural phase transition.

  238. Multiple scattering approach to Co K-edge XMCD and XANES spectra in Gd–Co alloys 査読有り

    Izumi Yamamoto, Shin-ichi Nagamatsu, Tetsuya Nakamura, Takashi Fujikawa, Susumu Nanao

    Journal of Electron Spectroscopy and Related Phenomena 125 (2) 89-98 2002年8月

    出版者・発行元:None

    DOI: 10.1016/S0368-2048(02)00092-0  

    ISSN:0368-2048

  239. Magnetic circular dichroism of resonant X-ray emission spectroscopy in longitudinal and transverse geometries 査読有り

    K Fukui, H Ogasawara, A Kotani, T Iwazumi, H Shoji, T Nakamura

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN 70 (11) 3457-3463 2001年11月

    出版者・発行元:PHYSICAL SOC JAPAN

    DOI: 10.1143/JPSJ.70.3457   10.1143/jpsj.70.3457  

    ISSN:0031-9015

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    Theoretical calculations and experimental measurements are performed for magnetic circular dichroism in resonant X-ray emission spectroscopy (MCD-RXES) in Gd3+ systems. It is shown that when the incident X-ray direction is perpendicular to the magnetization of the sample the MCD-RXES originates from the quantum mechanical interference which is characteristic of the coherent second order optical process, while when it is parallel to the magnetization the second order optical process reduces to the so-called two-step process with vanishing, interference effect. The behavior of MCD-RXES calculated for the 2p --&gt; 5d electric dipole excitation and 3d --&gt; 2p dipole radiative decay in Gd3+ is in good agreement with that measured experimentally for a Gd33Co67 amorphous alloy. The effects of the 2p --&gt; 4f electric quadrupole excitation and the 2p --&gt; is an element ofd electric dipole excitation are also studied.

  240. Magnetic circular dichroism of resonant X-ray emission spectroscopy in the transverse geometry 査読有り

    K Fukui, H Ogasawara, A Kotani, T Iwazumi, H Shoji, T Nakamura

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN 70 (5) 1230-1232 2001年5月

    出版者・発行元:PHYSICAL SOC JAPAN

    DOI: 10.1143/JPSJ.70.1230   10.1143/jpsj.70.1230  

    ISSN:0031-9015

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    We perform theoretical calculations and experimental measurements for magnetic circular dichroism in resonant X-ray. emission spectroscopy (MCD-RXES) in Gd3+ systems. A general expression of MCD-RXES is obtained theoretically for arbitrary directions of incident and emitted X-rays with an atomic model. It is shown that when the incident X-ray is perpendicular to the magnetization of the sample the MCD-RXES originates from the quantum mechanical interference between the excitation and decay processes. The behavior of MCD-RXES calculated for the 2p --&gt; 5d excitation and 3d --&gt; 2p radiative decay in Gd3+ is in good agreement with that measured experimentally for a Gd33Co67 amorphous alloy.

  241. Magnetic circular dichroism of 3ıt d$\sb 5/2$ $→$ 2ıt p$\sb 3/2$ resonant inelastic X-ray scattering at the Ho ıt L$\sb III$-edge in Ho$\sb 3$Fe$\sb 5$O$\sb 12$ 査読有り

    Nakamura Tetsuya, Kawamura Naomi, Iwazumi Toshiaki, Maruyama Hiroshi, Urata Akiri, Shoji Hironobu, Nanao Susumu, Kishimoto Shunji, Katano Rintaro, Isozumi Yasuhito

    Journal of Synchrotron Radiation 8 (2) 428-430 2001年3月

    出版者・発行元:None

    DOI: 10.1107/S0909049500018392  

    ISSN:0909-0495

  242. X-ray magnetic circular dichroism in quasicrystals 査読有り

    Y Watanabe, J Tamura, H Shoji, S Nanao, T Nakamura, Y Yokoyama

    MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING 294 617-620 2000年12月

    出版者・発行元:ELSEVIER SCIENCE SA

    DOI: 10.1016/S0921-5093(00)01103-5  

    ISSN:0921-5093

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    The spectra of X-ray magnetic circular dichroism (XMCD) and extended X-ray absorption fine structure (EXAFS) were measured in the ferromagnetic quasicrystals (a stable decagonal phase of Al40Mn25Fe15Ge20, a unstrained icosahedral phase of Al50Pd15Mn20B15, a strained icosahedral phase of Al42.5Pd7.5Mn30B20) and the orthorhombic approximant crystalline phase of Al30Mn40B30. In Al40Mn25Fe15Ge20, the intensity of XMCD at Mn K-edge and Fe K-edge were -7x10(-5) and -5x10(-5), respectively, which are normalized by the edge jump of the normal absorption spectra. The values suggest that Mn and Fe in this alloy contribute to the magnetism to the same degree. From the result of EXAFS, the nearest neighbors of Mn atoms and Fe atoms were analyzed to be at the same distance. The environment around Mn and Fe were found not so similar except for the nearest neighbor distance. In Al50Pd15Mn20B15, Al42.5Pd7.5Mn30B20 and Al30Mn40B30 alloys, the intensity of XMCD around the Mn K-edge were about -3x10(-4). The magnetic moments of Mn atoms in these alloys are roughly estimated to be 0.8 mu (B). The difference of a magnetic structure was detected between the quasicrystals and the approximant. The result of EXAFS analysis indicates that the distances from Mn to its first nearest neighbor and its second nearest neighbor are almost equal. The existence of phason strain field have no appreciable influence on the moment of Mn. (C) 2000 Elsevier Science B.V. All rights reserved.

  243. Magnetic circular dichroism of the x-ray-emission spectra for the 2p→1s decay in Co metal 査読有り

    T. Nakamura, H. Shoji, S. Nanao, T. Iwazumi, S. Kishimoto, R. Katano, Y. Isozumi

    Physical Review B - Condensed Matter and Materials Physics 62 (9) 5301-5304 2000年9月1日

    DOI: 10.1103/PhysRevB.62.5301  

    ISSN:0163-1829

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    The magnetic circular dichroism (MCD) of x-ray emission spectroscopy (XES) was measured at Co Kα1,2 (2p → 1s decay) in Co metal with the energies of the incident x rays chosen to be 7713 eV, 7720 eV, and 7730 eV around the Co K edge (7708 eV), respectively. The maximum amplitude of the MCD was about 0.25%, as was normalized by the peak heights of the Kα1 diagram line, and was on the same order as the MCD of the x-ray absorption spectra at the Co K edge. The MCDXES, which is quite weak due to the absence of a spin-orbit interaction in the 1 s state, originated from a weak spin-orbit interaction of the 4p state. The shapes of the observed MCD-XES were full of varieties depending on energies of incident x rays, where it was considered that they depended mainly on the multiplet effects as 2p-3d exchange interaction at the final state.

  244. Magnetic dichroism at Tb L-2.3-edges in Fe-Tb and Co-Tb amorphous thin films 査読有り

    CW Kim, T Nakamura, Y Watanabe

    JOURNAL OF THE KOREAN PHYSICAL SOCIETY 36 (4) 215-218 2000年4月

    出版者・発行元:KOREAN PHYSICAL SOC

    ISSN:0374-4884

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    In order to investigate the magnetic structures of the Fe-Tb and the Co-Tb amorphous alloy systems, we have measured the composition dependence of magnetic circular dichroism (MCD) spectra at the Tb L-2,L-3-edges. The MCD measurements show that the majority spin direction of the 5d(3/2)(5d(5/2))-projected electrons is parallel (anti-parallel) to the total moment in Tb-poor alloys, but anti-parallel (parallel) in Tb-rich alloy. The significant difference in the MCD intensities between the Fe-Tb and the Co-Tb alloy systems is thought to be associated with the difference in the populations of the conduction electrons between the two alloy systems.

  245. Magnetic circular dichroism of Gd 3d–2p and 4d–2p X-ray emission in ferrimagnetic Gd–Co amorphous 査読有り

    T Iwazumi, T Nakamura, H Shoji, K Kobayashi, S Kishimoto, R Katano, Y Isozumi, S Nanao

    Journal of Physics and Chemistry of Solids 61 (3) 453-456 2000年3月

    出版者・発行元:None

    DOI: 10.1016/S0022-3697(99)00335-2  

    ISSN:0022-3697

  246. Temperature Dependence of Magnetic Compoton Profile in DyCo<SUB>5</SUB>

    Hayato MIYAGAWA, Yasuhiro WATANABE, Akihisa KOIZUMI, Nobuhiko SAKAI, Masaichiro MIZUMAKI, Yoshiharu SAKURAI, Tetsuya NAKAMURA, Susumu NANAO

    Mat. Res. Soc. Symp. Proc. 658 (2000) GG5.10 2000年

  247. Evidence of antiferroquadrupolar ordering of DyB2C2 査読有り

    Y Tanaka, T Inami, T Nakamura, H Yamauchi, H Onodera, K Ohoyama, Y Yamaguchi

    JOURNAL OF PHYSICS-CONDENSED MATTER 11 (44) 505-511 1999年11月

    出版者・発行元:IOP PUBLISHING LTD

    DOI: 10.1088/0953-8984/11/44/102  

    ISSN:0953-8984

    eISSN:1361-648X

    詳細を見る 詳細を閉じる

    The antiferroquadrupolar ordering in DyB2C2 has been investigated using the x-ray resonant scattering technique. The dependence of the intensities of two superlattice peaks on temperature, azimuthal angle, and energy of the incident x-rays was measured. The results show that the antiferroquadrupole ordering, which accompanies a structural phase transition, exists below T-Q = 25 K. A structural model for the antiferroquadrupole ordering, for which the propagation vectors are (0, 0, 1/2) and (0, 1, 1/2), is presented.

  248. Scattering-angle dependence of the magnetic circular dichroism of resonant inelastic X-ray scattering 査読有り

    Toshiaki Iwazumi, Kenji Kobayashi, Teruo Tominaga, Tetsuya Nakamura, Susumu Nanao, Shunji Kishimoto, Daisuke Ohsawa, Rintarou Katano, Yasuhito Isozumi

    Journal of Synchrotron Radiation 6 (3) 685-687 1999年5月1日

    出版者・発行元:Blackwell Munksgaard

    DOI: 10.1107/S0909049599000023  

    ISSN:0909-0495

    詳細を見る 詳細を閉じる

    The scattering-angle dependence of the magnetic circular dichroism spectra of the resonant inelastic x-ray scattering in the Gd 3d-2p3/2 radiative transitions of the ferrimagnetic Gd-Co compound was observed when the incident x-ray energies were lower, exact and sufficiently higher than the Gd LIII absorption edge. The obtained results of not only the high-energy off-resonance, but also the low-energy off-resonance and the on-resonance, correspond well with the recent theoretical explanation for the high-energy off-resonant condition.

  249. X-ray magnetic Bragg scattering of SmFe2 査読有り

    H Miyagawa, T Tominaga, T Nakamura, Y Watanabe, M Ito, H Adachi, H Kawata, S Nakao

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 38 (S1) 440-443 1999年

    出版者・発行元:JAPAN J APPLIED PHYSICS

    DOI: 10.7567/jjaps.38s1.440  

    ISSN:0021-4922

    詳細を見る 詳細を閉じる

    X-rat non-resonant magnetic Bragg scattering was measured for SmFe2 which magnetic structure has not yet been st;died by neutron diffraction. The measurement was performed along the (h h 0) planes using white elliptically polarized synchrotron radiation at BL3C(2) (KEK-PF). From the profiles at the reflections (4h+2 4h+2 0) to which only Sm atom contributes, the form factors of the spin and orbital magnetic moments of Sm3+ have been directly deduced.

  250. Short range order of spin moments in NdCo2 studied by magnetic EXAFS 査読有り

    T Nakamura, Y Watanabe, M Mizumaki, S Nanao

    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS 38 (S1) 436-439 1999年

    出版者・発行元:JAPAN J APPLIED PHYSICS

    DOI: 10.7567/jjaps.38s1.436  

    ISSN:0021-4922

    詳細を見る 詳細を閉じる

    Magnetic Extended X-tay Absorption Fine Structure (MEXAFS) is a dichroic contribution to an x-ray absorption. The MEXAFS has been measured at Co K-edge in NdCo2 and at Fe EC-edge in iron thin film The Fourier analysis was carried out to obtain information about local magnetic structures in these systems. The positions and the sign of peaks in the imaginary part of Fourier transformed MEXAFS show a good agreement with those of conventional EXAFS for the iron thin film. In the case of NdCo2, the peak position for the nearest Nd shell was 2.89 Angstrom in the imaginary part of Fourier transformed MEXAFS, which is the same sign with corresponding peak in EXAFS. The fact that the sign of the peak was positive for the spin moments of Nd, which was not the absorption element, can be explained that the spin polarization of photoelectrons outgoing from the absorbing atoms is antiparallel to that of an absorbing Co atom in NdCo2.

  251. Distribution of spin polarization in ferrimagnetic DyFe2 by a novel analysis of magnetic EXAFS 査読有り

    T Nakamura, M Mizumaki, Y Watanabe, S Nanao

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN 67 (11) 3964-3968 1998年11月

    出版者・発行元:PHYSICAL SOC JAPAN

    DOI: 10.1143/JPSJ.67.3964  

    ISSN:0031-9015

    詳細を見る 詳細を閉じる

    Magnetic EXAFS (MEXAFS) at the Fe K-edge in DyFe2 powder and an Fe thin him were measured. In order to derive a ferrimagnetic coupling of spin moments between Dy and Fe from MEXAFS spectra, novel analysis for MEXAFS has been tried. The sigma(r) profiles, which are defined as the difference between the absolute values of Fourier transformed k(3)chi(+)(k) and k(3)chi(-) (k), were calculated for the measured spectra. chi(+)(k) and chi(-)(k) are EXAFS functions when the correlation between a X-ray beam and a magnetic field applied to a sample is parallel and anti-parallel, respectively. The sigma(r) has well described the distribution of spin polarization with its sign for ferrimagnetic DyFe2. A simulated distribution profile, in which only spin moments were considered, has been compared with the a(r) in DyFe2 and a good coincidence between them has been obtained. The sigma(r) profile for an Fe thin film completely reflects the ferromagnetic character and this result supports the validity of the present analysis.

  252. X-ray magnetic circular dichroism of multielectron excitation by fluorescence spectroscopy1Presented at the Todai Symposium 1997 and the 6th ISSP International Symposium on Frontiers in Synchrotron Radiation Spectroscopy, Tokyo, Japan, 27–30 October 1997. 査読有り

    T Nakamura, S Nanao, T Iwazumi, K Kobayashi, S Kishimoto, D Ohsawa, R Katano, Y Isozumi

    Journal of Electron Spectroscopy and Related Phenomena 92 (1-3) 261-264 1998年5月

    出版者・発行元:None

    DOI: 10.1016/S0368-2048(98)00133-9  

    ISSN:0368-2048

  253. Magnetic circular dichroism of lanthanoid Lβ2,15 fluorescence spectra of magnetic lanthanoid compounds1Presented at the Todai Symposium 1997 and the 6th ISSP International Symposium on Frontiers in Synchrotron Radiation Spectroscopy, Tokyo, Japan, 27–30 O 査読有り

    T Iwazumi, K Kobayashi, S Kishimoto, T Nakamura, S Nanao, D Ohsawa, R Katano, Y Isozumi, H Maruyama

    Journal of Electron Spectroscopy and Related Phenomena 92 (1-3) 257-260 1998年5月

    出版者・発行元:None

    DOI: 10.1016/S0368-2048(98)00132-7  

    ISSN:0368-2048

  254. Magnetic resonance effect in x-ray resonant Raman scattering 査読有り

    T Iwazumi, K Kobayashi, S Kishimoto, T Nakamura, S Nanao, D Ohsawa, R Katano, Y Isozumi

    PHYSICAL REVIEW B 56 (22) 14267-14270 1997年12月

    出版者・発行元:AMERICAN PHYSICAL SOC

    DOI: 10.1103/PhysRevB.56.R14267  

    ISSN:0163-1829

    詳細を見る 詳細を閉じる

    The magnetic-circular-dichroism spectra of the x-ray resonant Raman scattering associated with the Gd L alpha(1), L alpha(2), and L beta(2,15) fluorescence lines of the ferrimagnetic Gd-Co compound are presented. The incident x-ray energy dependence of these spectra clearly shows not only normal resonance effects, but also magnetic resonance effects between the excited 2p(3/2) electron and the 5d valence state, i.e., an enhancement of the magnetic effects and the appearance of a structure that corresponds to the magnetic effect of the total fluorescence yield.

  255. Effects of self-interaction correction on Compton profiles of diamond and silicon 査読有り

    Y Kubo, Y Sakurai, Y Tanaka, T Nakamura, H Kawata, N Shiotani

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN 66 (9) 2777-2780 1997年9月

    出版者・発行元:PHYSICAL SOC JAPAN

    DOI: 10.1143/JPSJ.66.2777   10.1143/jpsj.66.2777  

    ISSN:0031-9015

    詳細を見る 詳細を閉じる

    The full-potential linearized augmented-plane-wave (FLAPW) method is employed to find out effects of introducing the self-interaction correction (SIG) on the band structures, electron wavefunctions and Compton profiles of both diamond and silicon. To examine the computed results high-resolution Compton profiles of silicon along the [100], [110] and [111] directions are measured. In the case of silicon, it is found that theoretical Compton profiles computed with the SIC are in better agreement with the measured profiles when their first derivatives are compared. Although the effects of the SIC is much larger in the case of diamond, the theoretical prediction is to be tested by future high-resolution Compton profile measurements.

  256. Spin dependent EXAFS in DyFe2 査読有り

    T Nakamura, M Mizumaki, Y Watanabe, H Kimura, K Higashi, M Yoshimi, S Nanao

    JOURNAL DE PHYSIQUE IV 7 (C2) 425-426 1997年4月

    出版者・発行元:EDITIONS PHYSIQUE

    ISSN:1155-4339

    詳細を見る 詳細を閉じる

    The SPEXAFS in DyFe2 powder at the Fe K-edge was measured at 20 K and a high quality spectrum was obtained. The DyFe2 alloy has a crystalline structure of a C15 Laves phase and the spin moments of Fe ferrimagnetically couple with those of Dy. The pair distributions reflecting the sign of spin moments were derived for the first time by calculating the F(r) profile as the difference between the absolute value of Fourier transformed (k3)chi(+)(k) and (k3)chi(-)(k). In F(r), a negative peak and positive one were obtained at the position of Fe- (2.37 Angstrom) and Dy-(297 Angstrom) shells, respectively. The results confirm the validity of the present analytical method to obtain the pair distributions with the sign of spin moments. It extends the usefulness of SPEXAFS as a tool to study magnetic structures.

  257. Magnetic resonance effect in x-ray resonant Raman scattering 査読有り

    T. Iwazumi, K. Kobayashi, S. Kishimoto, T. Nakamura, S. Nanao

    Physical Review B - Condensed Matter and Materials Physics 56 (22) R14267-R14270 1997年

    DOI: 10.1103/PhysRevB.56.R14267  

    ISSN:1550-235X 1098-0121

    詳細を見る 詳細を閉じる

    The magnetic-circular-dichroism spectra of the x-ray resonant Raman scattering associated with the Gd (Formula presented) and (Formula presented) fluorescence lines of the ferrimagnetic Gd-Co compound are presented. The incident x-ray energy dependence of these spectra clearly shows not only normal resonance effects, but also magnetic resonance effects between the excited (Formula presented) electron and the (Formula presented) valence state, i.e., an enhancement of the magnetic effects and the appearance of a structure that corresponds to the magnetic effect of the total fluorescence yield. © 1997 The American Physical Society.

  258. Structure and magnetic properties of FeAl1−xRhx alloys 査読有り

    Salah A. Makhlouf, Tetsuya Nakamura, Masayuki Shiga

    Journal of Magnetism and Magnetic Materials 135 (3) 257-264 1994年8月

    出版者・発行元:None

    DOI: 10.1016/0304-8853(94)90355-7  

    ISSN:0304-8853

︎全件表示 ︎最初の5件までを表示

MISC 191

  1. 高周波MnZnフェライトの磁区構造解析 査読有り

    千葉龍矢, 村井健一, 三角彰太, 大河内拓雄, 中村哲也

    SPring-8/SACLA利用研究成果集(Web) 8 (2) 2020年

    ISSN:2187-6886

  2. 次世代放射光で進化する材料機能イメージング

    中村哲也

    資源・素材(Web) 2020 2020年

  3. 磁気閉回路を用いた残留磁化を有するバルク磁石の硬X線光電子分光計測技術の開発 査読有り

    保井晃, 保井晃, 池永英司, 上野若菜, 上野若菜, 辻成希, 小谷佳範, 広沢哲, 中村哲也, 中村哲也

    SPring-8/SACLA利用研究成果集(Web) 8 (2) 2020年

    ISSN:2187-6886

  4. マイクロ集光硬X線光電子分光実験のための高速ポジショニングシステムの開発 査読有り

    保井晃, 池永英司, 中村哲也

    SPring-8/SACLA利用研究成果集(Web) 8 (2) 2020年

    ISSN:2187-6886

  5. 硬X線磁気トモグラフィによる極微細粒Nd-Fe-B焼結磁石の三次元磁区観察

    竹内誠, 芳賀僚太, 菊池伸明, 岡本聡, 鈴木基寛, 小林慎太郎, 中村哲也, 中村哲也, 大久保忠勝, 埋橋淳, 宇根康裕

    電気学会研究会資料 (MAG-20-108-115) 2020年

  6. 軟X線MCD顕微分光による熱間加工磁石の磁化過程観察 (マグネティックス研究会 ナノスケール構造磁性体,永久磁石,磁性材料,磁気応用一般)

    竹内 誠, 蓬田 貴裕, 菊池 伸明, 岡本 聡, 北上 修, 豊木 研太郎, 小林 慎太郎, 小谷 佳範, 中村 哲也, 服部 篤, 日置 敬子

    電気学会研究会資料. MAG = The papers of technical meeting on magnetics, IEE Japan 2019 (79) 51-55 2019年8月8日

    出版者・発行元:電気学会

  7. バルク磁性体試料に対する深さ分解XMCD測定の開発

    鈴木基寛, 保井晃, 中村哲也

    SPring-8/SACLA利用研究成果集(Web) 7 (1) 2019年

    ISSN:2187-6886

  8. 磁気円二色性によるキラル磁性体CrNb<sub>3</sub>S<sub>6</sub>の元素選択磁気測定

    美藤正樹, 美藤正樹, 大隅寛幸, 鶴田一樹, 小谷佳範, 中村哲也, 戸川欣彦, 戸川欣彦, 篠嵜美沙子, 加藤雄介, 加藤雄介, 岸根順一郎, 岸根順一郎, 大江純一郎, 高阪勇輔, 高阪勇輔, 秋光純, 井上克也, 井上克也

    日本物理学会講演概要集(CD-ROM) 73 (1) ROMBUNNO.25aK304‐7 2018年3月23日

    ISSN:2189-079X

  9. Pt/Cr<sub>2</sub>O<sub>3</sub>積層膜における非線形ホール効果とX線MCD測定

    白土優, 青野晃, 森山貴広, 鈴木基寛, 中村哲也, 小野輝男, 中谷亮一

    日本金属学会講演概要(CD-ROM) 162nd ROMBUNNO.257 2018年3月5日

    ISSN:1342-5730

  10. 軟X線走査型MCD顕微鏡によるSm‐Co系焼結磁石の磁区観察

    加藤涼, 木田潤一郎, 中村哲也, 梶原堅太郎, 隅谷和嗣, 松浦裕, 田村隆治

    日本金属学会講演概要(CD-ROM) 162nd ROMBUNNO.268 2018年3月5日

    ISSN:1342-5730

  11. 軟X線磁気円二色性によるキラル磁性体CrNb<sub>3</sub>S<sub>6</sub>の軌道角運動量の観測

    美藤正樹, 美藤正樹, 大隅寛幸, 鶴田一樹, 小谷佳範, 中村哲也, 戸川欣彦, 戸川欣彦, 獅子堂達也, 黒田文彬, 岸根順一郎, 岸根順一郎, 高阪勇輔, 高阪勇輔, 秋光純, 井上克也, 井上克也

    日本物理学会講演概要集(CD-ROM) 73 (2) 2018年

    ISSN:2189-079X

  12. Microscopic Origin of Interfacial Dzyaloshinskii-Moriya Interaction

    Sanghoon Kim, Kohei Ueda, Gyungchoon Go, Peong-Hwa Jang, Kyung-Jin Lee, Abderrezak Belabbes, Aurelien Manchon, Motohiro Suzuki, Yoshinori Kotani, Tetsuya Nakamura, Kohji Nakamura, Tomohiro Koyama, Daichi Chiba, Kihiro Yamada, Duck-Ho Kim, Takahiro Moriyama, Kab-Jin Kim, Teruo Ono

    2017年4月11日

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    Chiral spin textures at the interface between ferromagnetic and heavy<br /> nonmagnetic metals, such as Neel-type domain walls and skyrmions, have been<br /> studied intensively because of their great potential for future nanomagnetic<br /> devices. The Dyzaloshinskii-Moriya interaction (DMI) is an essential phenomenon<br /> for the formation of such chiral spin textures. In spite of recent theoretical<br /> progress aiming at understanding the microscopic origin of the DMI, an<br /> experimental investigation unravelling the physics at stake is still required.<br /> Here, we experimentally demonstrate the close correlation of the DMI with the<br /> anisotropy of the orbital magnetic moment and with the magnetic dipole moment<br /> of the ferromagnetic metal. The density functional theory and the tight-binding<br /> model calculations reveal that asymmetric electron occupation in orbitals gives<br /> rise to this correlation.

  13. Nd<sub>2</sub>Fe<sub>14</sub>Bの電子密度分布の温度依存性

    岡崎宏之, 上野若菜, 辻成希, 中村哲也, 中村哲也, 杉本邦久, 河口彰吾, 広沢哲

    日本金属学会講演概要(CD-ROM) 160th ROMBUNNO.S1.6 2017年3月1日

    ISSN:2433-3093

  14. XMCD検出によるESR測定法の開拓 査読有り

    野尻浩之, BAKER Michael, 松澤智, 鳴海康雄, 中村哲也

    SPring-8/SACLA利用研究成果集(Web) 5 (1) 2017年

    ISSN:2187-6886

  15. Nd‐Fe‐B焼結磁石におけるNd<sub>2</sub>Fe<sub>14</sub>Bの電子密度分布解析

    岡崎宏之, 上野若菜, 辻成希, 中村哲也, 中村哲也, 杉本邦久, 河口彰吾, 広沢哲

    日本金属学会講演概要(CD-ROM) 158th ROMBUNNO.S1.23 2016年3月9日

    ISSN:2433-3093

  16. 電子誘電体RFe<sub>2</sub>O<sub>4</sub>の強磁場軟X線磁気円二色性

    鳴海 康雄, 藤原 孝将, 神戸 高志, 池田 直, 安村 光正, 野尻 浩之, 小谷 佳範, 中村 哲也

    日本物理学会講演概要集 71 1718-1718 2016年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.71.2.0_1718  

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    <p>強誘電性と磁気秩序が共存する混合原子価化合物RFe_2_O_4_(R=Le, Yb)に関して、特異な磁気ヒステリシスの起源を探ることを目的として、最大30Tのパルス強磁場を用いた軟X線磁気二色性測定を行ったので、その結果に関して報告する。</p>

  17. 極低温パルス磁場軟X線磁気円二色性装置の開発とCe化合物のメタ磁性転移への応用

    安村 光正, 野尻 浩之, 鳴海 康雄, 小谷 佳範, 中村 哲也

    日本物理学会講演概要集 71 1027-1027 2016年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.71.2.0_1027  

    詳細を見る 詳細を閉じる

    <p>我々は、元素選択的に磁気モーメントが決定できる分光学的手法である軟X線磁気円二色性測定を2 K以下の超低温領域で実現するため、装置開発を行ってきた。その開発経過に関して2015年秋季大会にて発表を行ったが、その後試料冷却機構の改良とオンサイトでの検証実験を行い、磁場印加時の信号取得に課題を残しながらも、試料部1.9 Kでの測定に成功した。講演では、装置の詳細を説明し、今後の課題と物性測定への応用について議論する。</p>

  18. Tb錯体から成る単分子磁石の軟X線磁気円二色性による磁気特性解析 査読有り

    加藤恵一, 鈴木基寛, 中村哲也, 辻成希, 小谷佳範, 山下正廣

    SPring-8/SACLA利用研究成果集(Web) 4 (2) 199-202 2016年

    ISSN:2187-6886

  19. 19aAU-10 垂直磁化フェリ磁性GdFeCo薄膜に光誘起される巨大スピン波

    大河内 拓雄, Schneider C. M, 黒田 寛人, Arguelles E. F, 坂上 護, 笠井 秀明, 菅 滋正, 木下 豊彦, 藤原 秀紀, 小嗣 真人, Adam R, 高橋 宏和, 角田 匡清, 塚本 新, 関山 明, 中村 哲也

    日本物理学会講演概要集 71 (0) 1005-1005 2016年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.71.1.0_1005  

    ISSN:2189-079X

  20. Signature of high $T_c$ around 25K in higher quality heavily boron-doped diamond 査読有り

    H. Okazaki, T. Wakita, T. Muro, T. Nakamura, Y. Muraoka, T. Yokoya, S. Kurihara, H. Kawarada, T. Oguchi, Y. Takano

    Appl. Phys. Lett. 2015年2月

  21. 21pAH-2 フェリ磁性体合金GdFeCoのM殻共鳴磁気光学スペクトルの研究

    山本 真吾, 田口 宗孝, 久保田 雄也, 伊藤 俊, 染谷 隆史, 藤澤 正美, 保原 麗, 中村 哲也, 加藤 剛志, 岩田 聡, 山本 達, 辛 埴, 松田 巌

    日本物理学会講演概要集 70 1065-1065 2015年

    出版者・発行元:一般社団法人日本物理学会

    DOI: 10.11316/jpsgaiyo.70.1.0_1065  

    ISSN:2189-079X

  22. 23pBJ-11 軟X線磁気円二色性用両極性パルス強磁場の開発

    安村 光正, 野尻 浩之, 鳴海 康雄, 中村 哲也, 小谷 佳範, 木下 豊彦

    日本物理学会講演概要集 70 1219-1219 2015年

    出版者・発行元:一般社団法人日本物理学会

    DOI: 10.11316/jpsgaiyo.70.1.0_1219  

    ISSN:2189-079X

  23. Nd-Fe-B焼結磁石における副相形成過程の放射光X線解析

    上野若菜, 辻成希, 中村哲也, 中村哲也, 杉本邦久, 藤原明比古, 宝野和博, 広沢哲

    日本金属学会講演概要(CD-ROM) 156th 2015年

    ISSN:2433-3093

  24. BL25SU(軟X線固体分光ビームライン)の現状(2014) 査読有り

    中村哲也, 室隆桂之, 大河内拓雄, 小谷佳範, 辻成希, 木下豊彦, 松下智裕, 仙波泰徳, 大橋治彦

    SPring-8/SACLA利用研究成果集(Web) 3 (1) 2015年

    ISSN:2187-6886

  25. 21pPSA-33 軟X線光電子顕微鏡によるフェリ磁性体GdFeCoのレーザー励起磁化反転機構の組成・温度依存性の研究

    八木 智弘, 大沢 仁志, Schneider Claus M, 関山 明, 菅 滋正, 木下 豊彦, 大河内 拓雄, 藤原 秀紀, 小嗣 真人, Adam Roman, 高橋 宏和, 角田 匡清, 塚本 新, 中村 哲也

    日本物理学会講演概要集 70 (0) 1106-1106 2015年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.70.1.0_1106  

    ISSN:2189-079X

  26. 10aPS-4 R_2Fe_<14>B(R=Nd, Dy, Ce, Pr)におけるR, Fe元素の 磁気モーメントの温度依存性(10aPS 領域5ポスターセッション(放射光,光電子分光,発光,非線形光学,フォトニック結晶),領域5(光物性))

    加藤 瞬弥, 寺嶋 健成, 矢野 正雄, 門野 利治, 藤田 茜, 渡辺 英治, 加田 大昌, 中村 哲也, WANG Jing, LIANG Le, ZHAN Canting, 今田 真

    日本物理学会講演概要集 69 (2) 536-536 2014年8月22日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  27. 9aBA-11 パルス強磁場軟X線MCDによるLuFe_2O_4の価数選択強磁場磁化測定(9aBA フラストレーション(三角格子),領域3(磁性))

    鳴海 康雄, 野尻 浩之, 中村 哲也, 広野 等子, 木下 豊彦, 深田 幸正, 永田 知子, 神戸 高志, 池田 直, 金道 浩一

    日本物理学会講演概要集 69 (2) 299-299 2014年8月22日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  28. 9aBC-4 シード型自由電子レーザーを用いたGdFeCoのM殻共鳴時間分解磁気光学効果の研究(9aBC 酸化物,化合物磁性,領域3(磁性))

    山本 真吾, 染谷 隆史, 和達 大樹, 藤澤 正美, Capotondi Flavio, Pedersoli Emanuele, Manfredda Michele, Caslari Francesco, 保原 麗, 中村 哲也, 加藤 剛志, 山本 達, Kiskinova Maya Petrova, 辛 埴, 松田 巌

    日本物理学会講演概要集 69 (2) 300-300 2014年8月22日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  29. 7aBK-2 Eu(Rh_<1-x>Ir_x)_2Si_2の磁場誘起価数転移における表面とバルクの比較(7aBK Eu系化合物(価数転移,磁性),領域8(強相関系))

    安村 光正, 鳴海 康雄, 野尻 浩之, 中村 哲也, 小谷 佳範, 保井 晃, 喜舎場 英吾, 光田 暁弘, 和田 裕文, 金道 浩一

    日本物理学会講演概要集 69 (2) 328-328 2014年8月22日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  30. 27aPS-4 Au,Ag(001)/超薄bcc-Fe(001)積層膜における表面偏析のXASによる解析(27aPS 領域3ポスターセッション,領域3(磁性))

    Bonell F., Lam D. D., 吉田 田茂, 高橋 良彰, 塩田 陽一, 中村 哲也, 三輪 真嗣, 鈴木 義茂

    日本物理学会講演概要集 69 (1) 475-475 2014年3月5日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  31. 29pAY-10 マルチフェロイック物質TbMnO_3の40T軟X線分光測定(29pAY 領域3,領域8合同 マルチフェロイクス,領域3(磁性))

    鳴海 康雄, 安村 光正, 野尻 浩之, 中村 哲也, 小谷 佳範, 辻 成希, 木下 豊彦, 井山 彩人, 木村 剛, 吉川 明子, 北澤 英明

    日本物理学会講演概要集 69 (1) 532-532 2014年3月5日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  32. 30aCM-9 超伝導ダイヤモンドの結晶性によるT_cの変化(30aCM 超伝導物質,領域8(強相関係))

    岡崎 宏之, 脇田 高徳, 園山 純生, 濱田 貴裕, 橘高 朋子, 村岡 祐治, 横谷 尚睦, 室 隆桂之, 中村 哲也, 栗原 槙一郎, 川原田 洋, 山口 尚秀, 竹屋 浩幸, 高野 義彦

    日本物理学会講演概要集 69 (1) 675-675 2014年3月5日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  33. 27pAF-11 強磁場軟X線吸収・磁気円二色性によるEu(Rh_<1-x>Ir_x)_2Si_2の価数転移の研究(27pAF 酸化物磁性・f電子系磁性,領域3(磁性))

    安村 光正, 鳴海 康雄, 野尻 浩之, 中村 哲也, 小谷 佳範, 木下 豊彦, 喜舎場 英吾, 光田 暁弘, 和田 裕文, 金道 浩一

    日本物理学会講演概要集 69 (1) 509-509 2014年3月5日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  34. 27aPS-121 高次高調波を用いた内殻共鳴磁気光学測定装置開発と時間分解への展望(27aPS 領域3ポスターセッション,領域3(磁性))

    山本 真吾, 染谷 隆史, 板谷 治郎, 保原 麗, 藤澤 正美, 吉田 力矢, 山本 貴士, 中村 哲也, 角田 匡清, 山本 達, 辛 埴, 松田 巌

    日本物理学会講演概要集 69 (1) 503-503 2014年3月5日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  35. パルス強磁場軟X線分光による表面・界面磁性研究の開拓 (特集 X線吸収分光法の最前線)

    中村 哲也, 鳴海 康雄

    表面科学 = Journal of the Surface Science Society of Japan 35 (5) 158-163 2014年

    出版者・発行元:日本表面科学会

    DOI: 10.1380/jsssj.35.158  

    ISSN:0388-5321

  36. 7pPSA-26 軟X線光電子顕微鏡によるフェリ磁性体GdFeCoのレーザー励起磁化反転機構の研究(7pPSA 領域3ポスターセッション(スピントロニクス,表面・界面磁性,実験技術,磁性一般),領域3(磁性))

    八木 智弘, 大沢 仁志, Schneider Claus M, 関山 明, 菅 滋正, 木下 豊彦, 大河内 拓雄, 藤原 秀紀, 小嗣 真人, Adam Roman, 高橋 宏和, 角田 匡清, 塚本 新, 中村 哲也

    日本物理学会講演概要集 69 (0) 279-279 2014年

    出版者・発行元:一般社団法人 日本物理学会

    ISSN:1342-8349

  37. 26pKM-11 Fe42カゴ状クラスターの強磁性と混合原子化(量子スピン(二次元系など),領域3(磁性,磁気共鳴))

    野尻 浩之, Baker M., 田中 卓也, 松澤 智, 鳴海 康雄, 中村 哲也, 佐藤 治

    日本物理学会講演概要集 68 (2) 410-410 2013年8月26日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  38. 25aEB-2 T_c=25Kの超伝導ダイヤモンドの角度分解光電子分光(超電導物質1,領域8(強相関系分野:高温超伝導,強相関f電子系など))

    岡崎 宏之, 脇田 高徳, 園山 純生, 濱田 貴裕, 橘高 朋子, 村岡 祐治, 横谷 尚睦, 室 隆桂之, 中村 哲也, 栗原 槙一郎, 川原田 洋, 山口 尚秀, 竹屋 浩幸, 高野 義彦

    日本物理学会講演概要集 68 (2) 440-440 2013年8月26日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  39. 25aKQ-9 軟X線磁気円二色性によるTbMnO_3の元素選択強磁場磁化測定(合同セッション マルチフェロ,領域8,領域3合同,領域8(強相関系分野:高温超伝導,強相関f電子系など))

    鳴海 康雄, 齋藤 康太, 野尻 浩之, 中村 哲也, 小谷 佳範, 辻 成希, 木下 豊彦, 井山 彩人, 木村 剛, 吉川 明子, 北澤 英明

    日本物理学会講演概要集 68 (2) 450-450 2013年8月26日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  40. 25pPSB-68 40Tパルス強磁場軟X線磁気円二色性測定装置の開発とその応用(領域3ポスターセッション(量子スピン・フラストレーション・スピングラス・f電子・酸化物・化合物磁性),領域3(磁性,磁気共鳴))

    鳴海 康雄, 安村 光正, 野尻 浩之, 中村 哲也, 小谷 佳範, 木下 豊彦, 金道 浩一

    日本物理学会講演概要集 68 (2) 396-396 2013年8月26日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  41. 25pKM-14 Nd-Fe-B永久磁石の軟X線MCDスペクトル(遍歴磁性,領域3(磁性,磁気共鳴))

    保井 晃, 小谷 佳範, 木下 豊彦, 中村 哲也, 広沢 哲

    日本物理学会講演概要集 68 (2) 379-379 2013年8月26日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  42. 27pXW-9 軟X線磁気円二色性によるTbMnO_3の元素選択強磁場磁化測定(27pXW 三角格子・マルチフェロイック・2次元量子系,領域3(磁性,磁気共鳴))

    鳴海 康雄, 齋藤 康太, 野尻 浩之, 中村 哲也, 小谷 佳範, 辻 成希, 木下 豊彦, 井山 彩人, 木村 剛, 吉川 明子, 北澤 英明

    日本物理学会講演概要集 68 (1) 548-548 2013年3月26日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  43. 26pEJ-10 SASE型自由電子レーザーを用いた磁気光学効果測定システムの開発(26pEJ 光誘起相転移(酸化物・強相関・超伝導),領域5(光物性))

    山本 真吾, 藤澤 正美, 保原 麗, 山本 達, 中村 哲也, 藤川 和志, 湯川 龍, 田口 宗孝, 大浦 正樹, 富樫 格, 角田 匡清, 辛 埴, 松田 巌

    日本物理学会講演概要集 68 (1) 801-801 2013年3月26日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  44. 軽イオンマイクロビーム照射によるFeRh合金薄膜への面内微細磁気構造の作製とPEEM観察

    小出哲也, 唐木淳志, 唐木淳志, 岩瀬彰宏, 松井利之, 佐藤隆博, 江夏昌志, 斎藤勇一, 神谷富裕, 大河内拓雄, 小嗣真人, 中村哲也, 木下豊彦

    日本金属学会講演概要(CD-ROM) 152nd 2013年

    ISSN:2433-3093

  45. 26pPSB-12 軟X線光電子顕微鏡による垂直磁化GdFeCo薄膜の磁化反転ダイナミクスの観測(領域5ポスターセッション(放射光,光電子分光,発光,非線形,フォトニック結晶),領域5(光物性))

    大河内 拓雄, 大沢 仁志, Schneider Claus M, 菅滋 正, 木下 豊彦, 藤原 秀紀, 小嗣 真人, Adam Roman, 高橋 宏和, 角田 匡清, 塚本 新, 関山 明, 中村 哲也

    日本物理学会講演概要集 68 (0) 670-670 2013年

    出版者・発行元:一般社団法人 日本物理学会

    ISSN:1342-8349

  46. 25aPS-40 X線磁気円二色性によるL1_0型FeNi規則合金薄膜の磁気異方性評価(領域3ポスターセッション(スピントロニクス・表面・界面磁性・マルチフェロイクス・遍歴磁性・磁性一般),領域3(磁性,磁気共鳴))

    大槻 匠, 白井 正文, 高梨 弘毅, 小嶋 隆幸, 小嗣 真人, 大河内 拓雄, 中村 哲也, 荻原 美沙子, 田代 敬之, 水口 将輝, 三浦 良雄

    日本物理学会講演概要集 68 (0) 370-370 2013年

    出版者・発行元:一般社団法人 日本物理学会

    ISSN:1342-8349

  47. 25pKM-13 強磁場軟X線MCDによるNd-Fe-B焼結磁石の粒界磁気物性(遍歴磁性,領域3(磁性,磁気共鳴))

    中村 哲也, 広沢 哲, 保井 晃, 小谷 佳範, 大河内 拓雄, 鳴海 康雄, 野尻 浩之, 木下 豊彦, 大久保 忠勝, 宝野 和博

    日本物理学会講演概要集 68 (0) 379-379 2013年

    出版者・発行元:一般社団法人 日本物理学会

    ISSN:1342-8349

  48. 28aKM-6 垂直磁化GdFeCo薄膜の光誘起磁化反転ダイナミクスの補償温度依存性(表面磁性(表面・界面・ナノ粒子),領域3,領域9合同,領域3(磁性,磁気共鳴))

    大河内 拓雄, 大沢 仁志, Schneider Claus M, 菅 滋正, 木下 豊彦, 藤原 秀紀, 小嗣 真人, Adam Roman, 高橋 宏和, 角田 匡清, 塚本 新, 関山 明, 中村 哲也

    日本物理学会講演概要集 68 (0) 433-433 2013年

    出版者・発行元:一般社団法人 日本物理学会

    ISSN:1342-8349

  49. 18aPSA-54 Soft X-ray High Magnetic Field MCD for Charge Transfer Type Fe-Co Complex

    野尻 浩之, Baker M.L., 田添 昂, 鳴海 康雄, 中村 哲也

    日本物理学会講演概要集 67 (2) 390-390 2012年8月24日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  50. 19pCD-5 強磁場軟X線MCDによる三角格子反強磁性体CuFeO_2のスピン・軌道状態の解明(19pCD マルチフェロイック,領域3(磁性,磁気共鳴))

    鳴海 康雄, 森岡 貴之, 野尻 浩之, 中村 哲也, 広野 等子, 木下 豊彦, 寺田 典機, 北澤 英明, 金道 浩一

    日本物理学会講演概要集 67 (2) 420-420 2012年8月24日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  51. 19pCD-8 強磁場軟X線MCDによるLuFe_2O_4の保磁力の評価(19pCD マルチフェロイック,領域3(磁性,磁気共鳴))

    齋藤 康太, 森岡 貴之, 鳴海 康雄, 野尻 浩之, 中村 哲也, 広野 等子, 木下 豊彦, 深田 幸正, 永田 知子, 神戸 高志, 池田 直, 金道 浩一

    日本物理学会講演概要集 67 (2) 421-421 2012年8月24日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  52. 18pPSA-45 40Tパルス強磁場軟X線磁気円二色性測定装置の開発(18pPSA 領域3ポスターセッション(スピントロニクス・薄膜・人工格子・表面・スピングラス・磁気共鳴・実験技術・磁性一般),領域3(磁性,磁気共鳴))

    鳴海 康雄, 齋藤 康太, 野尻 浩之, 中村 哲也, 小谷 佳範, 広野 等子, 木下 豊彦, 金道 浩一

    日本物理学会講演概要集 67 (2) 410-410 2012年8月24日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  53. レアメタルフリー酸化物反強磁性体を用いた垂直交換バイアス薄膜の開発

    白土 優, 中谷 亮一, 三俣 千春, 中村 哲也, 木下 豊彦, 鈴木 基寛, 鳴海 康雄, 野尻 浩之

    日本磁気学会研究会資料 = Bulletin of Topical Symposium of the Magnetics Society of Japan 185 41-46 2012年7月19日

    ISSN:1882-2940

  54. 27aAF-8 三角格子反強磁性体CuFeO_2の軟X線磁気円二色性測定(27aAF フラストレーション系(マルチフェロイック・三角格子系),領域3(磁性,磁気共鳴))

    鳴海 康雄, 森岡 貴之, 野尻 浩之, 中村 哲也, 広野 等子, 木下 豊彦, 寺田 典機, 北澤 英明, 金道 浩一

    日本物理学会講演概要集 67 (1) 536-536 2012年3月5日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  55. 27aAF-3 電荷秩序型マルチフェロイック物質LuFe_2O_4の価数選択強磁場磁化測定(27aAF フラストレーション系(マルチフェロイック・三角格子系),領域3(磁性,磁気共鳴))

    齋藤 康太, 鳴海 康雄, 野尻 浩之, 中村 哲也, 広野 等子, 木下 豊彦, 深田 幸正, 永田 知子, 神戸 高志, 池田 直, 田畑 吉計, 金道 浩一

    日本物理学会講演概要集 67 (1) 535-535 2012年3月5日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  56. 25aAF-4 Fe-Co1次元錯体のスピンクロスオーバー転移における誘電異常とXMCD(25aAF 量子スピン系,領域3(磁性,磁気共鳴))

    田添 昂, 野尻 浩之, Baker M., 鳴海 康雄, 田中 豪, 大塩 算紀, 飯島 史周, 中村 哲也, 広野 等子, 木下 豊彦, 金道 浩一

    日本物理学会講演概要集 67 (1) 507-507 2012年3月5日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  57. FeRh合金薄膜上におけるイオンビーム照射誘起面内微細磁気構造のXMCD-PEEM観察

    唐木淳志, 愛甲一馬, 松井利之, 岩瀬彰宏, 大河内拓雄, 小嗣真人, 中村哲也, 木下豊彦

    日本金属学会講演概要(CD-ROM) 151st 2012年

    ISSN:2433-3093

  58. 18pPSA-9 レーザー励起磁化反転によるGdFeCo薄膜の磁区形成と逆ファラデー効果(18pPSA 領域3ポスターセッション(スピントロニクス・薄膜・人工格子・表面・スピングラス・磁気共鳴・実験技術・磁性一般),領域3(磁性,磁気共鳴))

    大河内 拓雄, 大沢 仁志, Schncider Claus M, 木下 豊彦, 菅 滋正, 藤原 秀紀, 小嗣 真人, Adam Roman, 高橋 宏和, 角田 匡清, 塚本 新, 関山 明, 中村 哲也

    日本物理学会講演概要集 67 (0) 402-402 2012年

    出版者・発行元:一般社団法人 日本物理学会

    ISSN:1342-8349

  59. ミクロンサイズ磁気円盤配列における磁気ダイナミクスの時間分解光電子顕微鏡観測

    新井 邦明, 奥田 太一, 福本 恵紀, 小嗣 真人, 大河内 拓雄, 児玉 謙司, 春山 雄一, 中村 哲也, 松下 智裕, 大沢 仁志, 室隆 桂之, 松井 真二, 柿崎 明人, 大谷 義近, 木下 豊彦

    放射光 24 (2) 98-100 2011年3月31日

    出版者・発行元:日本放射光学会

    ISSN:0914-9287

  60. 23pJB-12 円偏光パルスレーザーによるGdFeCo薄膜の高速磁化反転のダイナミクス(23pJB 領域9,領域3合同 表面磁性,領域9(表面・界面,結晶成長))

    大河内 拓雄, 福島 和亮, 山口 淳一, 磯上 慎二, 中村 哲也, 児玉 謙司, 藤原 秀紀, 菅 滋正, 木下 豊彦, 小嗣 真人, 角田 匡清, 塚本 新, 関山 明, 新井 邦明

    日本物理学会講演概要集 66 (0) 936-936 2011年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.66.2.4.0_936_3  

    ISSN:1342-8349

  61. 25aHE-8 パルス強磁場XMCDによるCo(S,Se)_2のメタ磁性転移の観測(25aHE スピングラス・f電子系・遍歴磁性,領域3(磁性,磁気共鳴))

    鳴海 康雄, 木下 豊彦, 中村 哲也, 林 美咲, 野尻 浩之, 児玉 謙司, 広野 等子, 平賀 晴弘, 山田 和芳, 金道 浩一

    日本物理学会講演概要集 66 (0) 452-452 2011年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.66.1.3.0_452_4  

    ISSN:1342-8349

  62. 25aPS-66 30Tパルス強磁場軟X線MCD装置の開発(25aPS-3 領域3ポスターセッション,領域3(磁性,磁気共鳴))

    林 美咲, 森岡 貴之, 鳴海 康雄, 野尻 浩之, 中村 哲也, 広野 等子, 木下 豊彦, 児玉 謙司, 金道 浩一

    日本物理学会講演概要集 66 (0) 471-471 2011年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.66.1.3.0_471_3  

    ISSN:1342-8349

  63. 28aHE-3 Co/Ru多層膜の非磁性Ru層における誘起磁気分極成分の軟X線MCD測定(28aHE 領域3,領域9合同 表面・界面磁性,領域3(磁性,磁気共鳴))

    山岸 隆一郎, 福井 一生, 細糸 信好, 中村 哲也

    日本物理学会講演概要集 66 (0) 512-512 2011年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.66.1.3.0_512_4  

    ISSN:1342-8349

  64. 28aHE-4 パルスレーザーを用いた垂直磁化GdFeCo薄膜の光誘起磁化反転(28aHE 領域3,領域9合同 表面・界面磁性,領域3(磁性,磁気共鳴))

    大河内 拓雄, 福島 和亮, 山口 淳一, 磯上 慎二, 中村 哲也, 児玉 謙司, 藤原 秀紀, 菅 滋正, 木下 豊彦, 小嗣 真人, 角田 匡清, 塚本 新, 関山 明, 新井 邦明

    日本物理学会講演概要集 66 (0) 513-513 2011年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.66.1.3.0_513_1  

    ISSN:1342-8349

  65. 28aHE-3 Co/Ru多層膜の非磁性Ru層における誘起磁気分極成分の軟X線MCD測定(28aHE 領域3,領域9合同 表面・界面磁性,領域9(表面・界面,結晶成長))

    山岸 隆一郎, 福井 一生, 細糸 信好, 中村 哲也

    日本物理学会講演概要集 66 (0) 938-938 2011年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.66.1.4.0_938_1  

    ISSN:1342-8349

  66. 21aPS-134 30T軟X線MCD測定に向けた強磁場発生技術開発(21aPS 領域3ポスターセッション,領域3(磁性,磁気共鳴))

    鳴海 康雄, Hayashi Misaki, 森岡 貴之, 齋藤 康太, 野尻 浩之, 中村 哲也, 広野 等子, 木下 豊彦, 児玉 謙司, 金道 浩一

    日本物理学会講演概要集 66 (0) 404-404 2011年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.66.2.3.0_404_2  

    ISSN:1342-8349

  67. 21pRA-4 パルス強磁場軟X線MCDで見るCo(S,Se)_2のメタ磁性転移(21pRA 遍歴磁性・スピングラス,領域3(磁性,磁気共鳴))

    鳴海 康雄, Hayashi Misaki, 中村 哲也, 野尻 浩之, 児玉 謙司, 広野 等子, 平賀 晴弘, 山田 和芳, 金道 浩一, 木下 豊彦

    日本物理学会講演概要集 66 (0) 413-413 2011年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.66.2.3.0_413_2  

    ISSN:1342-8349

  68. 23pRA-11 Co/Ru多層膜におけるRu誘起磁気分極成分の軟X線MCD測定(23pRA スピントロニクス(スピントルク・電流誘起ダイナミクス・薄膜・微粒子),領域3(磁性,磁気共鳴))

    山岸 隆一郎, 福井 一生, 細糸 信好, 中村 哲也

    日本物理学会講演概要集 66 (0) 451-451 2011年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.66.2.3.0_451_4  

    ISSN:1342-8349

  69. 23aTC-4 パルス強磁場によるEuNi_2(Si_<0.18>Ge_<0.82>)_2の軟X線吸収MCD実験(23aTC 放射光真空紫外分光・MCD,領域5(光物性))

    中村 哲也, 木下 豊彦, 和田 裕文, 金道 浩一, 野尻 浩之, 小谷 章雄, 鳴海 康雄, 林 美咲, 光田 暁弘, 広野 等子, 児玉 謙司, 森岡 貴之, 齋藤 康太, 田添 昂

    日本物理学会講演概要集 66 (0) 776-776 2011年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.66.2.4.0_776_2  

    ISSN:1342-8349

  70. 23aTC-5 パルス強磁場によるEuNi_2(Si_<0.18>Ge_<0.82>)_2の軟X線吸収MCD実験の理論解析(23aTC 放射光真空紫外分光・MCD,領域5(光物性))

    小谷 章雄, 和田 裕文, 金道 浩一, 野尻 浩之, 中村 哲也, 鳴海 康雄, 林 美咲, 光田 暁弘, 広野 等子, 児玉 謙司, 森岡 貴之, 木下 豊彦

    日本物理学会講演概要集 66 (0) 776-776 2011年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.66.2.4.0_776_3  

    ISSN:1342-8349

  71. 23pJB-2 Ag(110)基板上に形成した鉄フタロシアニン二分子膜のスピン状態(23pJB 領域9,領域3合同表面磁性,領域3(磁性,磁気共鳴))

    福嶋 徹, 酒井 真利, 能登 健一, 塚原 規志, 白木 将, 中村 哲也, 木下 豊彦, 高木 紀明, 川合 眞紀

    日本物理学会講演概要集 66 (0) 446-446 2011年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.66.2.3.0_446_3  

    ISSN:1342-8349

  72. 28aHE-4 パルスレーザーを用いた垂直磁化GdFeCo薄膜の光誘起磁化反転(28aHE 領域3,領域9合同 表面・界面磁性,領域9(表面・界面,結晶成長))

    大河内 拓雄, 福島 和亮, 山口 淳一, 磯上 慎二, 中村 哲也, 児玉 謙司, 藤原 秀紀, 菅 滋正, 木下 豊彦, 小嗣 真人, 角田 匡清, 塚本 新, 関山 明, 新井 邦明

    日本物理学会講演概要集 66 (0) 938-938 2011年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.66.1.4.0_938_2  

    ISSN:1342-8349

  73. パルスマグネットを用いた強磁場軟X線MCD測定技術の開発

    中村哲也, 鳴海康雄, 広野等子, 児玉謙司, 林美咲, 磯上慎二, 高橋宏和, 角田匡清, 伊東航, 梅津理恵, 金道浩一, 貝沼亮介, 野尻浩之, 木下豊彦

    日本磁気学会学術講演概要集 34th 83 2010年9月4日

    ISSN:1882-2959

  74. 22pGC-5 X線MCD法で見る逆ペロフスカイト型化合物の磁性状態(22pGC 遍歴磁性・化合物磁性,領域3(磁性,磁気共鳴))

    芝山 隆史, 竹中 康司, 児玉 謙司, 中村 哲也, 木下 豊彦

    日本物理学会講演概要集 65 (0) 484-484 2010年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.65.1.3.0_484_4  

    ISSN:1342-8349

  75. 20pGE-2 CaRuO_3のFe置換による強磁性発現におけるRuの磁気状態(20pGE ルテニウム酸化物,領域8(強相関系:高温超伝導,強相関f電子系など))

    水崎 壮一郎, 平岡 望, 小澤 忠, 佐俣 博章, 野呂 良彦, 大西 智弘, 岡田 直哉, 永田 勇二郎, 谷口 貴士, 伊藤 真義, 櫻井 吉晴, 児玉 謙司, 中村 哲也

    日本物理学会講演概要集 65 (0) 556-556 2010年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.65.1.3.0_556_2  

    ISSN:1342-8349

  76. 23pWL-7 軟X線分光実験用パルス強磁場システム(23pWL 実験技術・磁性一般,領域3(磁性,磁気共鳴))

    林 美咲, 鳴海 康雄, 野尻 浩之, 中村 哲也, 広野 等子, 木下 豊彦, 児玉 謙司, 金道 浩一

    日本物理学会講演概要集 65 (0) 369-369 2010年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.65.2.3.0_369_3  

    ISSN:1342-8349

  77. 25aPS-21 Cu(110)表面に吸着したFeフタロシアニン分子の磁性(25aPS 領域3ポスターセッション,領域3(磁性,磁気共鳴))

    白木 将, 高木 紀明, 川合 真紀, 福嶋 徹, 能登 健一, 酒井 真利, 伊藤 彩夏, 塚原 規志, 中村 哲也, 児玉 謙司, 木下 豊彦

    日本物理学会講演概要集 65 (0) 403-403 2010年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.65.2.3.0_403_2  

    ISSN:1342-8349

  78. 25pWX-4 Ag(110)基板に展開した鉄フタロシアニン分子の磁気異方性(25pWX 領域9,領域3合同 表面磁性,領域3(磁性,磁気共鳴))

    福嶋 徹, 酒井 真利, 能登 健一, 塚原 規志, 白木 将, 中村 哲也, 木下 豊彦, 高木 紀明, 川合 眞紀

    日本物理学会講演概要集 65 (0) 428-428 2010年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.65.2.3.0_428_2  

    ISSN:1342-8349

  79. 25pWX-4 Ag(110)基板に展開した鉄フタロシアニン分子の磁気異方性(25pWX 領域9,領域3合同 表面磁性,領域9(表面・界面,結晶成長))

    福嶋 徹, 酒井 真利, 能登 健一, 塚原 規志, 白木 将, 中村 哲也, 木下 豊彦, 高木 紀明, 川合 眞紀

    日本物理学会講演概要集 65 (0) 878-878 2010年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.65.2.4.0_878_3  

    ISSN:1342-8349

  80. 23pWL-9 NiCoMnInメタ磁性形状記憶合金の元素選択強磁場磁化測定(23pWL 実験技術・磁性一般,領域3(磁性,磁気共鳴))

    鳴海 康雄, 金道 浩一, 木下 豊彦, 中村 哲也, 林 美咲, 野尻 浩之, 児玉 謙司, 広野 等子, 伊東 航, 梅津 理恵, 貝沼 亮介

    日本物理学会講演概要集 65 (0) 370-370 2010年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.65.2.3.0_370_1  

    ISSN:1342-8349

  81. 23pRG-8 パルス強磁場を用いた軟X線MCD測定技術の開発(23pRG 光電子分光・放射光真空紫外分光・MCD・X線発光,領域5(光物性))

    中村 哲也, 梅津 理恵, 金道 浩一, 貝沼 亮介, 野尻 浩之, 木下 豊彦, 鳴海 康雄, 広野 等子, 児玉 謙司, 林 美咲, 磯上 慎二, 高橋 宏和, 角田 匡清, 伊東 航

    日本物理学会講演概要集 65 (0) 683-683 2010年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.65.2.4.0_683_3  

    ISSN:1342-8349

  82. Fabrication of perpendiculary magnetized magnetic tunnel junctions with L10-CoPt/Co2MnSi hybrid electrode

    T. Hiratsuka, G. Kim, Y. Sakuraba, T. Kubota, K. Kodama, N. Inami, H. Naganuma, M. Oogane, T. Nakamura, K. Takanashi, Y. Ando

    Journal of Applied Physics 2010年

  83. 27pPSB-12 Au表面に形成したMnナノワイヤの磁性(27pPSB 領域3ポスターセッション,領域3(磁性,磁気共鳴))

    白木 将, 広瀬 正明, 中村 哲也, 室隆 桂之, 南任 真史, 川合 真紀

    日本物理学会講演概要集 64 (0) 462-462 2009年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.64.1.3.0_462_4  

    ISSN:1342-8349

  84. 28pTH-8 逆ペロフスカイト型マンガン窒化物Mn_3CuNのXMCD解析(28pTH 遍歴電子系・f電子系,領域3(磁性,磁気共鳴))

    中村 哲也, 浅野 和子, 竹中 康司, 児玉 謙司, 木下 豊彦

    日本物理学会講演概要集 64 (0) 502-502 2009年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.64.1.3.0_502_2  

    ISSN:1342-8349

  85. 27pPSA-44 パルス強磁場下での軟X線MCD測定技術の開発(領域3ポスターセッション(量子スピン系・フラストレーション系等),領域3,磁性,磁気共鳴)

    中村 哲也, 鳴海 康雄, 広野 等子, 児玉 謙司, 林 美咲, 角田 匡清, 金道 浩一, 野尻 浩之, 木下 豊彦

    日本物理学会講演概要集 64 (0) 391-391 2009年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.64.2.3.0_391_2  

    ISSN:1342-8349

  86. 26pXA-12 X線磁気二色性,線二色性,及び光電子顕微鏡を用いたNiO(100)における反強磁性磁区構造の詳細観察(新分光法,MCD/MLD,領域5,光物性)

    新井 邦明, 室 隆桂之, 柿崎 明人, 田中 新, 木下 豊彦, 奥田 太一, 小嗣 真人, 福本 恵紀, 大浦 正樹, 仙波 泰徳, 大橋 治彦, 中村 哲也, 松下 智裕

    日本物理学会講演概要集 64 (0) 637-637 2009年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.64.2.4.0_637_3  

    ISSN:1342-8349

  87. 27aPS-2 鉄フタロシアニン薄膜のXAS/XMCD測定(領域5ポスターセッション,領域5,光物性)

    白木 将, 川合 真紀, 酒井 真利, 能登 健一, 伊藤 彩夏, 塚原 規志, 児玉 謙司, 中村 哲也, 木下 豊彦, 高木 紀明

    日本物理学会講演概要集 64 (0) 645-645 2009年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.64.2.4.0_645_2  

    ISSN:1342-8349

  88. 27pYE-8 グラファイトインターカレーション超伝導体CaC_6の共鳴光電子分光(グラフェン電子物性(形成と評価),領域7,分子性固体・有機導体)

    岡崎 宏之, 高野 義彦, 冨岡 史明, 竹中 麻美, 豊田 昌宏, 小口 多美夫, 横谷 尚睦, 吉田 力矢, 岩井 啓介, 野網 健吾, 室 隆桂之, 中村 哲也, 脇田 高徳, 村岡 祐治, 平井 正明

    日本物理学会講演概要集 64 (0) 783-783 2009年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.64.2.4.0_783_3  

    ISSN:1342-8349

  89. The Third Magnetic Phase of GaGdN Detected by SX-MCD

    M. Takahashi, Y. Hiromura, S. Emura, T. Nakamura, Y. K. Zhou, S. Hasegawa, H. Asahi

    PHYSICS OF SEMICONDUCTORS 1199 411-+ 2009年

    出版者・発行元:AMER INST PHYSICS

    DOI: 10.1063/1.3295478  

    ISSN:0094-243X

    詳細を見る 詳細を閉じる

    Magnetic circular dichroism (MCD) under the transition between the core levels (3d - 4f) of Gd+3 ion in diluted magnetic semiconductor GaGdN is observed in the energy range of 1160 - 1240 eV. The intensity of the MCD signals reaches up to 30% at 15K, suggesting strong magnetic behavior. The temperature dependence of its intensity is not on a simple Curie-Weiss curve. A step like form around 40 - 100K is found, suggesting a new magnetic phase.

  90. 28pRE-8 硬X線フーリエ変換ホログラフィー法の開発(28pRE 領域10,領域5合同 X線・粒子線(X線),領域10(誘電体,格子欠陥,X線・粒子線,フォノン物性))

    鈴木 基寛, 磯上 慎二, 角田 匡清, 野村 健二, 淡路 直樹, 中村 哲也

    日本物理学会講演概要集 64 (0) 955-955 2009年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.64.1.4.0_955_4  

    ISSN:1342-8349

  91. 20aXA-11 MCD,XRDを用いた隕石由来L1_0型FeNi相の電子スピン状態の研究(20aXA 領域9,領域3合同 表面磁性,領域3(磁性,磁気共鳴))

    小嗣 真人, 水牧 仁一朗, 大坂 恵一, 中村 哲也, 河村 直己, 鈴木 基寛, 石松 直樹, 圓山 裕, 渡辺 義夫

    日本物理学会講演概要集 63 (0) 362-362 2008年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.63.2.3.0_362_3  

    ISSN:1342-8349

  92. 21pQG-13 静磁気的に結合したミクロンサイズ磁気円盤配列における磁気渦コアダイナミクスの観測(21pQG スピントロニクス・微小領域磁性,領域3(磁性,磁気共鳴))

    新井 邦明, 柿崎 明人, 木下 豊彦, 福本 恵紀, 奥田 太一, 中村 哲也, 木村 崇, 松下 智裕, 大沢 仁志, 室隆 桂之, 大谷 義近

    日本物理学会講演概要集 63 (0) 381-381 2008年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.63.2.3.0_381_3  

    ISSN:1342-8349

  93. 21pPSA-14 Fe/NiO(100)界面における交換結合状態(21pPSA 領域3ポスターセッション,領域3(磁性,磁気共鳴))

    新井 邦明, 福本 恵紀, 奥田 太一, 松下 智裕, 中村 哲也, 室 隆桂之, 柿崎 明人, 木下 豊彦

    日本物理学会講演概要集 63 (0) 388-388 2008年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.63.2.3.0_388_1  

    ISSN:1342-8349

  94. 21aWF-4 高分解能光電子分光によるグラファイトインターカレーション超伝導体C_6Caの電子状態(21aWF フラーレン・超伝導,領域7(分子性固体・有機導体))

    岡崎 宏之, 高野 義彦, 竹中 麻美, 豊田 昌宏, 小口 多美夫, 横谷 尚睦, 吉田 力矢, 岩井 啓介, 野網 健悟, 室 隆桂之, 中村 哲也, 村岡 祐治, 平井 正明, 冨岡 史明

    日本物理学会講演概要集 63 (0) 747-747 2008年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.63.2.4.0_747_1  

    ISSN:1342-8349

  95. 20aXA-11 MCD,XRDを用いた隕石由来L1_0型FeNi相の電子スピン状態の研究(20aXA 領域9,領域3合同 表面磁性,領域9(表面・界面,結晶成長))

    小嗣 真人, 水牧 仁一朗, 大坂 恵一, 中村 哲也, 河村 直己, 鈴木 基寛, 石松 直樹, 圓山 裕, 渡辺 義夫

    日本物理学会講演概要集 63 (0) 796-796 2008年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.63.2.4.0_796_3  

    ISSN:1342-8349

  96. 22aPS-22 フーリエ変換ホログラフィーによる磁気ドメイン観察の試行(22aPS 領域5ポスターセッション,領域5(光物性))

    中村 哲也, 鈴木 基寛, 淡路 直樹, 土井 修一, 野村 健二, 磯上 慎二, 角田 匡清

    日本物理学会講演概要集 63 (0) 655-655 2008年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.63.2.4.0_655_1  

    ISSN:1342-8349

  97. 19pWF-6 Ca_<1.5>Sr_<0.5>RuO_4の軟X線角度分解光電子分光によるバルクフェルミ面・スペクトル形状(19pWF Ru系,領域8(強相関系:高温超伝導,強相関f電子系など))

    漆間 正行, 菅 滋正, 関山 明, 藤原 秀紀, 矢野 正雄, 藤田 浩史, 今田 真, 室 隆桂之, 中村 哲也, 前野 悦輝

    日本物理学会講演概要集 62 (0) 590-590 2007年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.62.1.3.0_590_1  

    ISSN:1342-8349

  98. 19aWF-5 高濃度ボロンドープダイヤモンドの軟X線角度分解光電子分光(19aWF ドープダイヤモンド,領域8(強相関系:高温超伝導,強相関f電子系など))

    横谷 尚睦, 小口 多美夫, 岡崎 宏之, 中村 哲也, 室 隆桂之, 松下 智裕, 高野 義彦, 長尾 雅則, 竹之内 智大, 川原田 洋

    日本物理学会講演概要集 62 (0) 545-545 2007年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.62.1.3.0_545_2  

    ISSN:1342-8349

  99. 18aTB-2 Fe単原子ワイヤーの電子状態と磁性(18aTB 領域3,領域9合同 2.表面・界面磁性,領域3(磁性,磁気共鳴))

    南任 真史, 白木 将, 藤澤 英樹, 広瀬 正明, 中村 哲也, 室 隆桂之, 川合 真紀

    日本物理学会講演概要集 62 (0) 400-400 2007年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.62.1.3.0_400_2  

    ISSN:1342-8349

  100. 24pxA-2 軟X線光電子分光によるn型リンドープダイヤモンドの電子構造の研究(ダイヤモンド・Si超伝導,領域8,強相関係:高温超伝導,強相関f電子系など)

    岡崎 宏之, 山崎 聡, 高野 義彦, 石井 聡, 小口 多美夫, 横谷 尚睦, 室 隆桂之, 中村 哲也, 松下 智裕, 脇田 高徳, 村岡 祐治, 平井 正明, 加藤 宙光

    日本物理学会講演概要集 62 (0) 665-665 2007年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.62.2.3.0_665_2  

    ISSN:1342-8349

  101. 24pXA-1 高濃度ホウ素ドープダイヤモンドの軟X線光電子分光(ダイヤモンド・Si超伝導,領域8,強相関係:高温超伝導,強相関f電子系など)

    岡崎 宏之, 石井 聡, 入山 慎吾, 川原田 洋, 横谷 尚睦, 室 隆桂之, 中村 哲也, 松下 智裕, 脇田 高徳, 村岡 祐治, 平井 正明, 高野 義彦

    日本物理学会講演概要集 62 (0) 665-665 2007年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.62.2.3.0_665_1  

    ISSN:1342-8349

  102. 22aPS-72 反強磁性NiO表面上のFe超薄膜の磁化特性(領域3ポスターセッション(薄膜・人工格子,スピングラス,量子スピン系),領域3,磁性,磁気共鳴)

    福木 恵紀, 柿崎 明人, 木下 豊彦, 新井 邦明, 奥田 太一, 松下 智裕, 郭 方准, 大浦 正樹, 竹内 智之, 中村 哲也, 室 隆桂之

    日本物理学会講演概要集 62 (0) 475-475 2007年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.62.2.3.0_475_1  

    ISSN:1342-8349

  103. 21pPSB-75 Pdナノ粒子のX線磁気円二色性実験(領域3ポスターセッション(フラストレーション,磁気共鳴,実験技術,微小領域),領域3,磁性,磁気共鳴)

    大場 洋次郎, 岡本 啓明, 佐藤 徹哉, 中村 哲也, 大沢 仁志, 室 隆桂之, 篠原 武尚, 鈴木 淳市

    日本物理学会講演概要集 62 (0) 450-450 2007年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.62.2.3.0_450_3  

    ISSN:1342-8349

  104. 22aXK-2 Au(788)表面上に構築した3d遷移金属ナノ構造の磁性(表面磁性,表面界面電子物性,領域9,表面・界面,結晶成長)

    白木 将, 藤澤 英樹, 広瀬 正明, Usman Brianto, 南任 真史, 川合 真紀, 中村 哲也, 大沢 仁志, 室 隆桂之

    日本物理学会講演概要集 62 (0) 923-923 2007年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.62.2.4.0_923_2  

    ISSN:1342-8349

  105. 24aTK-10 放射光パルスとフェムト秒レーザーパルス同期による時間分解XMCD-PEEM(光電子分光・MCD,領域5,光物性)

    福本 恵紀, 木下 豊彦, 大沢 仁志, 松下 智裕, 新井 邦明, 中村 哲也, 室 隆桂之, 木村 崇, 大谷 義近, 柿崎 明人

    日本物理学会講演概要集 62 (0) 788-788 2007年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.62.2.4.0_788_2  

    ISSN:1342-8349

  106. 20aPS-7 Au(788)表面上に構築した3d遷移金属ナノ構造の磁性(ポスターセッション,領域9,表面・界面,結晶成長)

    白木 将, 室 隆桂之, 藤澤 英樹, 古川 雅士, 広瀬 正明, Usman Brian, 南任 真史, 川合 真紀, 中村 哲也, 大沢 仁志

    日本物理学会講演概要集 62 (0) 896-896 2007年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.62.1.4.0_896_1  

    ISSN:1342-8349

  107. 18aTB-2 Fe単原子ワイヤーの電子状態と磁性(領域3,領域9合同 2.表面・界面磁性,領域9,表面・界面,結晶成長)

    南任 真史, 白木 将, 藤澤 英樹, 広瀬 正明, 中村 哲也, 室 隆桂之, 川合 真紀

    日本物理学会講演概要集 62 (0) 868-868 2007年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.62.1.4.0_868_4  

    ISSN:1342-8349

  108. Mn_3Ir反強磁性合金による巨大交換バイアス

    角田 匡清, 三俣 千春, 中村 哲也, 高橋 研

    日本応用磁気学会研究会資料 150 19-28 2006年10月18日

    ISSN:1340-7562

  109. 25aXH-1 軌道Ferri磁性体CoMnO_3の電子状態の温度変化(25aXH 酸化物磁性・化合物磁性・f電子系磁性,領域3(磁性,磁気共鳴))

    水牧 仁一朗, 河村 直己, 魚住 孝幸, 佐藤 博彦, 中村 哲也, 伊藤 真義, 櫻井 吉晴

    日本物理学会講演概要集 61 (2) 357-357 2006年8月18日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  110. 軟X線磁気円二色性による磁気材料評価

    中村 哲也

    まぐね = Magnetics Japan 1 (3) 108-117 2006年3月1日

    出版者・発行元:日本応用磁気学会

    ISSN:1880-7208

  111. 金属系シナジー化合物の遍歴電子構造,相安定性と物性 Co<sub>2</sub>FeGaホイスラー合金の軟X線による内殻磁気円2色性

    梅津理恵, 小林恒誠, 及川勝成, 及川勝成, 藤田麻哉, 貝沼亮介, 貝沼亮介, 石田清仁, 石田清仁, 佐久間昭正, 深道和明, 中村哲也

    日本金属学会講演概要 138th 2006年

    ISSN:1342-5730

  112. 27pPSA-32 MnFeP_<0.78>Ge_<0.22>のL_<2,3>内殻吸収磁気円二色性(27pPSA 領域3ポスターセッション 薄膜・人工格子磁性,表面・界面磁性,微小領域磁性,遍歴磁性,化合物磁性,f電子系磁性磁性,領域3(磁性,磁気共鳴))

    恒川 雅典, Bruck Ekkes, 菅 滋正, 小山 佳一, 今田 真, 松本 惇, 山崎 篤志, 八窪 裕人, Schmid Benjamin, 東道 啓聡, 服部 芳郎, 中村 哲也

    日本物理学会講演概要集 61 (0) 442-442 2006年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.61.1.3.0_442_2  

    ISSN:1342-8349

  113. 27pPSA-33 Mn_<2.97>Co_<0.03>GaCの磁気円二色性および光電子分光(27pPSA 領域3ポスターセッション 薄膜・人工格子磁性,表面・界面磁性,微小領域磁性,遍歴磁性,化合物磁性,f電子系磁性磁性,領域3(磁性,磁気共鳴))

    松本 惇, 室 隆桂之, 菅 滋正, 今田 真, 恒川 雅典, 山崎 篤志, 東道 啓聡, 服部 芳郎, Schmid Benjamin, 和田 裕文, 中村 哲也

    日本物理学会講演概要集 61 (0) 442-442 2006年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.61.1.3.0_442_3  

    ISSN:1342-8349

  114. 26aYH-3 Au(788)表面上に形成した3d遷移金属ナノ構造の磁性(26aYH 領域3,領域9合同 表面・界面磁性,領域3(磁性,磁気共鳴))

    高山 英俊, 藤澤 英樹, 白木 将, 広瀬 正明, 南任 真史, 川合 真紀, 中村 哲也, 室 隆桂之

    日本物理学会講演概要集 61 (0) 376-376 2006年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.61.2.3.0_376_1  

    ISSN:1342-8349

  115. 27aTD-11 ホウ素ドープCVDダイヤモンド薄膜の角度分解光電子分光(27aTD ホウ化物,炭化物(超伝導),領域8(強相関系:高温超伝導,強相関f電子系など))

    横谷 尚睦, 松下 智裕, 高田 恭孝, 徳島 高, 辛 埴, 高野 義彦, 長尾 雅則, 竹之内 智大, 川原田 洋, 小口 多美夫, 岡崎 宏之, 川田 純也, 元光 邦彦, 中村 仁, 山田 修義, 中村 哲也, 室隆 桂之, 為則 雄祐

    日本物理学会講演概要集 61 (0) 511-511 2006年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.61.1.3.0_511_4  

    ISSN:1342-8349

  116. 27pTE-9 Fe_<2-x>Ti_xO_3固溶体中のTi^<4+>イオンの磁気分極(27pTE 磁気共鳴一般・実験技術開発・酸化物磁性,領域3(磁性,磁気共鳴))

    藤井 達生, 山下 美樹, 藤森 伸一, 齋藤 祐児, 中村 哲也, 小林 啓介, 高田 潤

    日本物理学会講演概要集 61 (0) 435-435 2006年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.61.1.3.0_435_1  

    ISSN:1342-8349

  117. 26aYH-3 Au(788)表面上に形成した3d遷移金属ナノ構造の磁性(26aYH 領域3,領域9合同 表面・界面磁性,領域9(表面・界面,結晶成長))

    高山 英俊, 藤澤 英樹, 白木 将, 広瀬 正明, 南任 真史, 川合 真紀, 中村 哲也, 室 隆桂之

    日本物理学会講演概要集 61 (0) 769-769 2006年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.61.2.4.0_769_1  

    ISSN:1342-8349

  118. 23aPS-42 Ce(Fe_<0.8>Co_<0.2>)_2の内殻吸収磁気円二色性(23aPS 領域3ポスターセッション(磁性),領域3(磁性,磁気共鳴))

    恒川 雅典, 室 隆桂之, 和田 裕文, 今田 真, 松本 惇, 山崎 篤志, 藤原 秀紀, 菅 滋正, Schmid Benjamin, 東道 啓聡, 中村 哲也

    日本物理学会講演概要集 61 (0) 323-323 2006年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.61.2.3.0_323_4  

    ISSN:1342-8349

  119. 24aXN-6 Au及びPtに挟まれたFe1原子層の軟X線磁気円二色性の温度変化(薄膜・人工格子磁性,表面・界面磁性,トンネル分光,領域3(磁性,磁気共鳴))

    渡辺 智健, 今田 真, 山崎 篤志, 税田 哲朗, 中村 哲也, 室 隆桂之, 嶋 敏之, 高梨 弘毅, 菅 滋正

    日本物理学会講演概要集 60 (0) 408-408 2005年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.60.1.3.0_408_2  

    ISSN:1342-8349

  120. 26pXN-15 軟X線MCDによるAl-Mn-Fe-Ge準結晶合金の元素別磁化解析(フラストレーション系(三角格子・カゴメ格子),スピングラス・ランダム系,領域3(磁性,磁気共鳴))

    中村 哲也, 横山 嘉彦, 鎌倉 望, 室 隆桂之, 松下 智裕, 広野 等子, 小林 啓介

    日本物理学会講演概要集 60 (0) 469-469 2005年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.60.1.3.0_469_2  

    ISSN:1342-8349

  121. 24aWA-8 硬x線光電子分光によるボロンドープ超伝導ダイヤモンド薄膜の電子状態(ホウ素・炭素系(超伝導・四極子),領域8(強相関系:高温超伝導,強相関f電子系など))

    横谷 尚睦, 長尾 雅則, 坂口 勲, 立木 実, 羽多野 毅, 竹之内 智大, 小林 健作, 梅沢 仁, 原田 洋, 池永 英司, 小畠 雅明, 小林 啓介, 竹内 晃久, 淡路 晃弘, 中村 哲也, 室 隆桂之, 高野 義彦

    日本物理学会講演概要集 60 (0) 488-488 2005年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.60.1.3.0_488_1  

    ISSN:1342-8349

  122. 26pXP-4 強磁性形状記憶合金Ni_2Mn_<0.5>Fe_<0.5>Gaの軟X線磁気円二色性(領域5, 領域3, 領域8合同招待講演,領域5(光物性))

    八窪 裕人, 今田 真, 渡邊 智健, Schmid Benjamin, 鹿又 武, 中村 哲也, 室 隆桂之, 菅 滋正

    日本物理学会講演概要集 60 (0) 709-709 2005年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.60.1.4.0_709_1  

    ISSN:1342-8349

  123. 26pXP-5 Coクラスター/Si(111)のXMCDスペクトル(領域5, 領域3, 領域8合同招待講演,領域5(光物性))

    望戸 力, 謝 天, 喬 山, 木村 昭夫, 生天目 博文, 谷口 雅樹, 中村 哲也, 斎藤 祐児, 竹田 幸治

    日本物理学会講演概要集 60 (0) 709-709 2005年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.60.1.4.0_709_2  

    ISSN:1342-8349

  124. 24aPS-169 Au(788)微傾斜表面上におけるFeナノ構造の磁性(表面・界面, 結晶成長,領域9(表面・界面, 結晶成長))

    藤澤 英樹, 白木 将, 伊藤 信太郎, 古川 雅士, 南任 真史, 川合 真紀, 室 隆桂之, 中村 哲也

    日本物理学会講演概要集 60 (0) 844-844 2005年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.60.1.4.0_844_3  

    ISSN:1342-8349

  125. 20pPSA-4 Cr_xTi_<1-x>N/MgOの電子状態(領域5ポスターセッション,領域5(光物性))

    崔 芸濤, 斎藤 祐児, 竹田 幸治, 小山 邦彦, 宮木 雄史, 田中 和馬, 犬丸 啓, 山中 昭司, 木村 昭夫, 宮本 幸治, 坂本 和昭, 謝 天, 喬 山, 島田 賢也, 谷口 雅樹, 中村 哲也

    日本物理学会講演概要集 60 (0) 582-582 2005年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.60.2.4.0_582_1  

    ISSN:1342-8349

  126. 19pYK-5 Al-Mn-Fe-Ge準結晶合金の軟X線MCD(準結晶(構造,電子物性,表面,空孔),領域6(金属,超低温,超伝導・密度波))

    山田 貴之, 七尾 進, 中村 哲也, 横山 嘉彦, 鎌倉 望, 室 隆桂之, 松下 智裕, 広野 等子, 小林 啓介, 渡辺 康裕

    日本物理学会講演概要集 60 (0) 635-635 2005年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.60.2.4.0_635_2  

    ISSN:1342-8349

  127. 20pXH-6 軟X線MCDによるナノ粒子、および、ナノワイヤーの高感度磁化解析(領域3,領域9合同シンポジウム,主題 : ナノスケールで発現する金属磁性,領域3(磁性,磁気共鳴))

    中村 哲也, 木下 豊彦, 小林 啓介, 藤澤 英樹, 白木 将, 山田 貴之, 室 隆桂之, 松下 智裕, 広野 等子, 川合 真紀, 七尾 進

    日本物理学会講演概要集 60 (0) 300-300 2005年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.60.2.3.0_300_1  

    ISSN:1342-8349

  128. SPring-8 BL25SU における軟X線元素選択磁化測定の現状

    中村 哲也, 室隆 桂之, 松下 智弘, 小林 啓介

    日本応用磁気学会学術講演概要集 = Digest of ... annual conference on magnetics in Japan 28 207-207 2004年9月21日

  129. 13pPSA-2 内殻励起磁気円二色性による Ce 化合物の磁性研究(領域 5)

    中村 聡, 中村 哲也, 室隆 桂之, 宮原 恒あき, 石井 広義, 高山 泰弘, 吉田 徹夫, 佐々木 直也, 佐藤 英行, 菊池 大輔, 塩澤 秀次

    日本物理学会講演概要集 59 (0) 656-656 2004年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.59.2.4.0_656_3  

    ISSN:1342-8349

  130. 12pWB-14 固体酸素における磁場誘起体積膨張(化合物磁性, 磁性半導体・絶縁体, 実験技術開発, 磁気共鳴一般, 磁性一般, 領域 3)

    木村 尚次郎, 北村 英男, 勝又 紘一, Staub U, 鳴海 康雄, 田中 良和, 下村 晋, 中村 哲也, Lovesey Stephen W, 石川 哲也

    日本物理学会講演概要集 59 (0) 375-375 2004年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.59.2.3.0_375_3  

    ISSN:1342-8349

  131. 27aPS-107 SPring-8 BL25SUにおける軟X線MCDによる元素選択磁化解析(領域3ポスターセッション : 希土類合金,化合物磁性,薄膜・人工格子,スピングラス,フラストレーション,量子スピン系,実験技術開発等)(領域3)

    中村 哲也, 室 隆桂之, 郭 方准, 松下 智裕, 脇田 高徳, 大橋 治彦, 小林 啓介

    日本物理学会講演概要集 59 (0) 460-460 2004年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.59.1.3.0_460_3  

    ISSN:1342-8349

  132. 30aXD-10 YB_2C_2の超伝導における同位元素効果(四極子秩序,関連物質)(領域8)

    吉川 明子, 中村 哲也, 鴫海 康雄, 勝又 紘一

    日本物理学会講演概要集 59 (0) 645-645 2004年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.59.1.3.0_645_1  

    ISSN:1342-8349

  133. 12aPS-74 軟 X 線による軌道 Ferri 磁性体 CoMnO_3 の電子状態の研究(磁性・磁気共鳴, 領域 3)

    水牧 仁一朗, 佐藤 博彦, 渡辺 峰旨, 河村 直己, 中村 哲也, 宮川 隼人, 安居院 あかね

    日本物理学会講演概要集 59 (0) 356-356 2004年

    出版者・発行元:一般社団法人 日本物理学会

    ISSN:1342-8349

  134. 22aWA-5 ポリマー被覆金ナノ微粒子の XMCD

    山本 良之, 三浦 尊裕, 鈴木 基寛, 河村 直己, 宮川 勇人, 中村 哲也, 小林 啓介, 堀 秀信

    日本物理学会講演概要集 58 (0) 410-410 2003年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.58.2.3.0_410_1  

    ISSN:1342-8349

  135. 21aWG-10 X 線共鳴散乱による HoB_2C_2 の多重極子の観察

    田中 良和, 田畑 吉計, 中村 哲也, 鳴海 康雄, 勝又 紘一, 玉作 賢治, 石川 哲也

    日本物理学会講演概要集 58 (0) 490-490 2003年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.58.2.3.0_490_1  

    ISSN:1342-8349

  136. 22pPSA-2 希土類価数揺動物質の局所帯磁率

    塩澤 秀次, 室 隆桂之, 斎藤 祐児, 海老原 孝雄, 宮原 恒〓, 中村 聡, 大坪 英雄, 高山 泰弘, 石井 広義, 菅原 仁, 佐藤 英行, 中村 哲也

    日本物理学会講演概要集 58 (0) 653-653 2003年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.58.2.4.0_653_2  

    ISSN:1342-8349

  137. 31aXG-2 CuGeO_3 の磁場中 X 線散乱

    鳴海 康雄, 原 徹, 田中 降次, 玉作 賢治, 矢橋 牧名, 後藤 俊治, 大橋 治彦, 竹下 邦和, 大端 通, 松下 智裕, 備前 輝彦, 勝又 紘一, 松田 雅昌, 田畑 吉計, 木村 尚次郎, 田中 良和, 中村 哲也, 下村 晋, 石川 哲也, 北村 英男

    日本物理学会講演概要集 58 (0) 471-471 2003年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.58.1.3.0_471_3  

    ISSN:1342-8349

  138. 28pYE-9 RbMnFe(CN)_6 の X 線発光、吸収分光による光誘起スピン状態転移観察 2

    大沢 仁志, 高野 剛次, 七尾 進, 五十棲 泰人, 所 裕子, 大越 慎一, 橋本 和仁, 野沢 俊介, 岩住 俊明, 中村 哲也, 小路 博信, 平井 栄樹

    日本物理学会講演概要集 58 (0) 690-690 2003年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.58.1.4.0_690_1  

    ISSN:1342-8349

  139. 8aSG-8 RbMnFe(CN)_6のX線発光、吸収分光による光誘起スピン状態転移観察(光誘起相転移,領域5)

    大沢 仁志, 小路 博信, 平井 栄樹, 中村 哲也, 七尾 進, 所 裕子, 大越 慎一, 橋本 和仁, 岩住 俊明, 五十棲 泰人

    日本物理学会講演概要集 57 (2) 635-635 2002年8月13日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  140. 7pPSA-19 Pd-Fe 合金のPdL発光磁気円二色性測定(領域5)

    岩住 俊明, 大沢 仁志, 小路 博信, 河村 直巳, 平井 栄樹, 中村 哲也, 七尾 進, 圓山 裕, 五十棲 泰人

    日本物理学会講演概要集 57 (2) 617-617 2002年8月13日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  141. 8aPS-113 X線MCDによるDyCo_5の元素選択磁化(遍歴磁性,化合物磁性,スピングラス・ランダム系,量子スピン系,磁気共鳴一般,実験技術開発等,領域3)

    中村 哲也, 河村 直己, 鈴木 基寛, 小路 博信, 香取 浩子, 七尾 進

    日本物理学会講演概要集 57 (2) 387-387 2002年8月13日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  142. 6aWB-8 中性子非弾性散乱によるDyB_2C_2の結晶場励起の観測(化合物磁性・f電子系,領域3)

    中村 哲也, 勝又 紘一, Staub U., Jurany F., Lovesey S.W.

    日本物理学会講演概要集 57 (2) 328-328 2002年8月13日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  143. 6pPA-2 メタ磁性体FeCl_2・2H_20の磁場中X線散乱(磁場中X線散乱,領域3)

    鳴海 康雄, 勝又 紘一, 宮川 勇人, 中村 哲也, 田中 良和, 下村 晋, 高垣 昌史, 石川 哲也, 矢橋 牧名

    日本物理学会講演概要集 57 (2) 333-333 2002年8月13日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  144. 24pXF-4 MnF_2の磁場中におけるX線磁気散乱(24pXF 化合物磁性・遷移金属酸化物・磁性一般,領域3(磁性,磁気共鳴分野))

    勝又 紘一, 田畑 吉計, 中村 哲也, 田中 良和, 下村 晋, 鳴海 康雄, 石川 哲也, 北村 英男, 原 徹, 田中 隆次, 玉作 賢治, 矢橋 牧名, 後藤 俊治, 大橋 治彦, 竹下 邦和, 大端 通, 松下 智裕, 備前 輝彦, Lovesey S. W., 山田 勲

    日本物理学会講演概要集 57 (1) 376-376 2002年3月1日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  145. 24pWB-9 共鳴X線散乱によるHoB_2C_2における四重極秩序の観測(24pWB 重い電子系(四極子秩序),領域8(強相関系分野-高温超伝導,強相関f電子系など))

    田畑 吉計, 田中 良和, 中村 哲也, 勝又 紘一, 下村 晋, 石川 哲也, 玉作 賢治, 鈴木 基寛, Lovesey S.W., 高垣 昌史

    日本物理学会講演概要集 57 (1) 497-497 2002年3月1日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  146. 26pPSA-31 RbMnFe(CN)_6のX線発光、吸収分光によるスピン転移観察(26pPSA,領域5(光物性分野))

    大沢 仁志, 小路 博信, 平井 栄樹, 中村 哲也, 七尾 進, 所 裕子, 大越 慎一, 橋本 和仁, 岩住 俊明, 五十棲 泰人

    日本物理学会講演概要集 57 (1) 700-700 2002年3月1日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  147. 26pPSA-13 Gd2P_<1/2>吸収端近傍におけるGd3d_<5/2>-2P_<3/2>発光の振る舞い(26pPSA,領域5(光物性分野))

    岩住 俊明, 中村 哲也, 小路 博信, 七尾 進, 五十棲 泰人

    日本物理学会講演概要集 57 (1) 696-696 2002年3月1日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  148. 26pPSA-15 Rh化合物の共鴫X線発光分光(26pPSA,領域5(光物性分野))

    平井 栄樹, 中村 哲也, 大沢 仁志, 岩住 俊明, 片野 林太郎, 五十棲 泰人, 七尾 進

    日本物理学会講演概要集 57 (1) 696-696 2002年3月1日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  149. 26pPSA-17 R-Co系アモルファス合金の発光MCD(26pPSA,領域5(光物性分野))

    中村 哲也, 小路 博信, 平井 栄樹, 大沢 仁志, 岩住 俊明, 片野 林太郎, 五十棲 泰人, 七尾 進

    日本物理学会講演概要集 57 (1) 697-697 2002年3月1日

    出版者・発行元:一般社団法人日本物理学会

    ISSN:1342-8349

  150. 共鳴X線非弾性(ラマン)散乱によるCuOの電子状態

    宇田川康夫, 武田留美, 林久史, 中村哲也, 小路博信, 宮川勇人, 七尾進, 河村直巳

    分子構造総合討論会講演要旨集 2002 2002年

  151. 17pZA-3 軟X線MCDよるSmFe_2の磁気モーメント評価

    宮川 勇人, 中村 哲也, 渡辺 康裕, 水牧 仁一郎, 室隆 桂之, 七尾 進

    日本物理学会講演概要集 56 (0) 326-326 2001年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.56.2.3.0_326_3  

    ISSN:1342-8349

  152. 17aRG-2 RAl_2, RFe_2のR L_<2,3>-edgeにおけるXMCD

    中村 哲也, 水牧 仁一朗, 河村 直己, 宮川 勇人, 渡辺 康裕, 七尾 進, 安達 弘通

    日本物理学会講演概要集 56 (0) 574-574 2001年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.56.2.4.0_574_4  

    ISSN:1342-8349

  153. 18aPS-42 鉄系スピンクロスオーバ錯体のX線発光、吸収分光によるスピン状態転移観察 2

    大沢 仁志, 五十棲 泰人, 七尾 進, 岩住 俊明, 小路 博信, 平井 栄樹, 中村 哲也, 小川 佳宏, 石川 忠彦, 腰原 伸也, 片野 林太郎

    日本物理学会講演概要集 56 (0) 600-600 2001年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.56.2.4.0_600_4  

    ISSN:1342-8349

  154. 28aXA-1 希上類アモルファス合金の希土類L吸収端における多電子励起磁気円二色性

    中村 哲也, 渡辺 康裕, 田村 純平, 平井 栄樹, 七尾 進, 水牧 仁一朗

    日本物理学会講演概要集 56 (0) 659-659 2001年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.56.1.4.0_659_4  

    ISSN:1342-8349

  155. 30aXC-8 多重散乱理論によるTb-Co系合金のCo K-edge XMCD解析

    永松 伸一, 藤川 高志, 中村 哲也

    日本物理学会講演概要集 56 (0) 880-880 2001年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.56.1.4.0_880_2  

    ISSN:1342-8349

  156. 磁気EXAFS

    七尾 進, 中村 哲也

    放射光 13 (1) 33-39 2000年2月29日

    出版者・発行元:日本放射光学会

    ISSN:0914-9287

  157. 22aE-4 DyCo_5のX線磁気コンプトン散乱

    宮川 勇人, 渡辺 康裕, 平岡 望, 小泉 昭久, 坂井 信彦, 水牧 仁一郎, 桜井 吉晴, 中村 哲也, 七尾 進

    日本物理学会講演概要集 55 (0) 325-325 2000年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.55.1.3.0_325_3  

    ISSN:1342-8349

  158. 22pM-5 Sm Lα_<1,2>の発光MCD

    中村 哲也, 岩住 俊明, 小路 博信, 渡辺 康裕, 水牧 仁一朗, 岸本 俊二, 片野 林太郎, 五十棲 泰人, 七尾 進

    日本物理学会講演概要集 55 (0) 617-617 2000年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.55.1.4.0_617_4  

    ISSN:1342-8349

  159. 22pM-15 Si単結晶のX線共鳴非弾性散乱 : 偏光相関・方位角依存性

    岩住 俊明, 小路 博信, 中村 哲也, 七尾 進, 岸本 俊二, 片野 林太郎, 五十棲 泰人

    日本物理学会講演概要集 55 (0) 620-620 2000年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.55.1.4.0_620_1  

    ISSN:1342-8349

  160. 25aQ-3 準結晶のX線発光分光測定

    渡辺 康裕, 中村 哲也, 小路 博信, 岩住 俊明, 水牧 仁一朗, 岸本 俊二, 片野 林太郎, 五十棲 泰人, 七尾 道

    日本物理学会講演概要集 55 (0) 692-692 2000年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.55.1.4.0_692_1  

    ISSN:1342-8349

  161. 25aW-8 Ni(110)における酸素吸着と初期酸化過程

    渡辺 一寿, 中村 哲也, 井口 玉美, 西山 雅之, 池田 佳子, 石井 康博, 柴田 真希子, 福谷 博仁

    日本物理学会講演概要集 55 (0) 806-806 2000年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.55.1.4.0_806_2  

    ISSN:1342-8349

  162. 22pXC-5 SmL_<II> L_<III>吸収端における2p4f四重極遷移の発光MCD

    中村 哲也, 岩住 俊明, 小路 博信, 渡辺 康裕, 水牧 仁一朗, 岸本 俊二, 片野 林太郎, 五十棲 泰人, 七尾 進

    日本物理学会講演概要集 55 (0) 604-604 2000年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.55.2.4.0_604_3  

    ISSN:1342-8349

  163. 23aXC-4 垂直配置X線発光磁気円二色性スペクトルの測定

    岩住 俊明, 小路 博信, 宮川 勇人, 中村 哲也, 七尾 准, 片野 林太郎, 五十棲 泰人

    日本物理学会講演概要集 55 (0) 612-612 2000年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.55.2.4.0_612_4  

    ISSN:1342-8349

  164. 24pPSB-60 CeFe_2の磁気EXAFSによる磁気構造の決定

    水牧 仁一朗, 中村 哲也, 宮川 勇人, 吉井 資次, 鈴木 基寛, 河村 直巳, 七尾 進

    日本物理学会講演概要集 55 (0) 409-409 2000年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.55.2.3.0_409_3  

    ISSN:1342-8349

  165. 放射光で磁性材料を調べる

    中村 哲也

    まてりあ : 日本金属学会会報 38 (9) 730-730 1999年9月20日

    ISSN:1340-2625

  166. Magnetic EXAFSでみる磁性体の磁気構造

    中村 哲也, 七尾 進

    日本応用磁気学会誌 23 (4) 906-912 1999年4月1日

    出版者・発行元:日本応用磁気学会

    ISSN:0285-0192

    詳細を見る 詳細を閉じる

    MCD measurement in extended X-ray absorption fine structure (EXAFS) energy range gives us information on the pair distribution of spin-polarized scattering sites around an absorption atom. Magnetic EXAFS at the Fe K-edge is presented for DyFe_2 powder and an Fe thin film, and the local magnetic structures are analyzed from the spectra. The positions and signs of peaks in the imaginary part of Fourier-transformed magnetic EXAFS agree well with those of conventional EXAFS for the iron thin film. In order to derive a ferrimagnetic coupling of spin moments between Dy and Fe from magnetic EXAFS spectra, the function σ(r) was defined as the difference between the absolute values of Fourier-transformed EXAFS functions for positive and negative helicities of circularly polarized X-rays. σ(r) accurately described the distribution of the spin polarization and its sign in ferrimagnetic DyFe_2.

  167. 25pYC-5 Mn化合物のX線共鳴非弾性散乱

    小路 博信, 岩住 俊明, 小林 憲司, 中村 哲也, 岸本 俊二, 片野 林太郎, 五十棲 素人, 七尾 進

    日本物理学会講演概要集 54 (0) 652-652 1999年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.54.2.4.0_652_3  

    ISSN:1342-8349

  168. 25pYC-14 発光MCDによるX線領域でのCoster-Kronig過程の検証

    中村 哲也, 岩住 俊明, 小路 博信, 岸本 俊二, 片野 林太郎, 五十棲 素人, 七尾 進

    日本物理学会講演概要集 54 (0) 654-654 1999年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.54.2.4.0_654_4  

    ISSN:1342-8349

  169. 28a-ZH-5 純コバルトにおけるCo Kα_<1, 2>の発光MCD

    中村 哲也, 岩住 俊明, 小路 博信, 岸本 俊二, 片野 林太郎, 五十僂 泰人, 七尾 進

    日本物理学会講演概要集 54 (0) 182-182 1999年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.54.1.2.0_182_4  

    ISSN:1342-8349

  170. 28p-ZH-7 Si 3p→1sX線共鳴非弾性散乱再実験

    岩住 俊明, 中村 哲也, 小路 博信, 岸本 俊二, 片野 林太郎, 五十棲 泰人, 七尾 進

    日本物理学会講演概要集 54 (0) 192-192 1999年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.54.1.2.0_192_3  

    ISSN:1342-8349

  171. 28p-ZH-8 X線共鳴非弾性散乱による遷移金属化合物の電子構造研究

    小路 博信, 小林 憲司, 中村 哲也, 岩住 俊明, 片野 林太郎, 五十棲 泰人, 岸本 俊二, 七尾 進

    日本物理学会講演概要集 54 (0) 192-192 1999年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.54.1.2.0_192_4  

    ISSN:1342-8349

  172. 26p-YK-5 SmFe_2のX線磁気ブラッグ散乱

    宮川 勇人, 富永 照男, 中村 哲也, 渡辺 康裕, 安達 弘通, 河田 洋, 伊藤 正久, 七尾 進

    日本物理学会講演概要集 53 (0) 509-509 1998年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.53.2.3.0_509_4  

    ISSN:1342-8349

  173. 26a-YP-13 強磁性Gd化合物のGdLα_<1.2>,β_1,β_<2.15>,γ_1発光MCD

    中村 哲也, 岩住 俊明, 小路 博信, 小林 憲司, 岸本 俊二, 片野 林太郎, 五十棲 泰人, 七尾 進

    日本物理学会講演概要集 53 (0) 226-226 1998年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.53.2.2.0_226_4  

    ISSN:1342-8349

  174. 26a-YP-14 アモルファスCo-GdのGdL吸収・発光MCDの組成依存性

    中村 哲也, 七尾 進, 小路 博信, 岩住 俊明, 小林 憲司, 岸本 俊二, 片野 林太郎, 五十棲 泰人, 水牧 仁一朗, 渡辺 康裕

    日本物理学会講演概要集 53 (0) 227-227 1998年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.53.2.2.0_227_1  

    ISSN:1342-8349

  175. 27a-K-11 X線磁気回折によるhcp-CoのLS分離

    伊藤 正久, 田中 良和, 松本 紳, 和光 信也, 春本 将彦, 宮川 勇人, 中村 哲也, 渡辺 康裕, 七尾 進, 安達 弘通, 森 丈晴, 河田 洋

    日本物理学会講演概要集 53 (0) 428-428 1998年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.53.2.2.0_428_1  

    ISSN:1342-8349

  176. 5p-G-13 希土類金属L_3-吸収端の共鳴発光分光

    小林 憲司, 岩住 俊明, 岸本 俊二, 中村 哲也, 七尾 進, 大沢 大輔, 片野 林太郎, 五十棲 泰人, 圓山 裕

    日本物理学会講演概要集 52 (0) 207-207 1997年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.52.2.2.0_207_1  

    ISSN:1342-8349

  177. 5p-G-14 X線共鳴ラマン散乱における磁気的共鳴効果

    岩住 俊明, 小林 憲司, 岸本 俊二, 中村 哲也, 七尾 進, 大沢 大輔, 片野 林太郎, 五十棲 泰人

    日本物理学会講演概要集 52 (0) 207-207 1997年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.52.2.2.0_207_2  

    ISSN:1342-8349

  178. 7p-X-6 蛍光分光法による多電子励起のX線磁気円二色性

    中村 哲也, 七尾 進, 岩住 俊明, 小林 憲司, 岸本 俊二, 大沢 大輔, 片野 林太郎, 五十棲 泰人

    日本物理学会講演概要集 52 (0) 403-403 1997年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.52.2.2.0_403_3  

    ISSN:1342-8349

  179. 7p-X-7 白色X線磁気回折によるhcp-TbのLS分離

    伊藤 正久, 藤井 俊行, 春本 将彦, 中村 哲也, 森 丈晴, 村上 洋一, 河田 洋

    日本物理学会講演概要集 52 (0) 403-403 1997年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.52.2.2.0_403_4  

    ISSN:1342-8349

  180. 30p-WE-9 2次元Deposition model におけるスケーリング則

    中村 哲也, 溝上 伸也, 大橋 弘忠

    日本物理学会講演概要集 52 (0) 727-727 1997年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.52.1.3.0_727_2  

    ISSN:1342-8349

  181. 31a-A-6 Fe, Co, Niと3d遷移金属化合物のXMCD測定と理論解析

    水牧 仁一朗, 藤川 高志, 畑田 圭介, 永松 伸一, 中村 哲也, 渡辺 康裕, 七尾 進

    日本物理学会講演概要集 52 (0) 388-388 1997年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyo.52.1.2.0_388_1  

    ISSN:1342-8349

  182. La_<1-x>Sr_xCoO_3の金属-絶縁体相転移によるMCDの変化

    水牧 仁一朗, 伊藤 正行, 中村 哲也, 吉見 学, 渡辺 康裕, 七尾 進

    日本物理学会講演概要集. 秋の分科会 1996 (0) 164-164 1996年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyoj.1996.2.0_164_2  

  183. X線磁気回折によるFeの磁気形状因子の異方性

    伊藤 正久, 七尾 進, 松本 紳, 和光 信也, 藤井 俊行, 春本 将彦, 橋本 英生, 中村 哲也, 河田 洋, 森 丈晴, 坂井 信彦, 伊藤 文武

    日本物理学会講演概要集. 秋の分科会 1996 (0) 675-675 1996年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyoj.1996.2.0_675_2  

  184. 白色X線磁気回折による強磁性Coの磁気形状因子

    伊藤 正久, 松本 紳, 和光 信也, 田中 良和, 藤井 俊行, 春本 将彦, 中村 哲也, 橋本 英生, 森 丈晴, 村上 洋一, 河田 洋

    日本物理学会講演概要集. 秋の分科会 1996 (0) 676-676 1996年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyoj.1996.2.0_676_1  

  185. 1a-Z-9 遷移金属ボロン化合物のMCD

    水牧 仁一朗, 中村 哲也, 木村 仁, 渡辺 康裕, 七尾 進

    日本物理学会講演概要集. 年会 51 (0) 262-262 1996年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyog.51.2.0_262_1  

  186. 1a-Z-11 DyFe_2のMagnetic EXAFS

    中村 哲也, 水牧 仁一朗, 渡辺 康裕, 木村 仁, 東 芳, 吉見 学, 七尾 進

    日本物理学会講演概要集. 年会 51 (0) 263-263 1996年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyog.51.2.0_263_1  

  187. 3a-W-8 白色X線磁気回折によるFeの磁気形状因子II

    伊藤 正久, 松本 紳, 和光 信也, 藤井 俊行, 橋本 英生, 中村 哲也, 河田 洋, 森 丈晴, 坂井 信彦, 伊藤 文武, 七尾 進

    日本物理学会講演概要集. 年会 51 (0) 587-587 1996年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyog.51.2.0_587_2  

  188. 27p-W-13 Fe_4NのMCD

    水牧 仁一郎, 中村 哲也, 木村 仁, 渡辺 康裕, 七尾 進

    日本物理学会講演概要集. 秋の分科会 1995 (0) 244-244 1995年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyoj.1995.2.0_244_1  

  189. 5a-X-1 TM-REアモルファス磁性薄膜の硬X線磁気吸収

    中村 哲也, 水牧 仁一朗, 賀茂 尚広, 渡辺 康裕, 七尾 進

    日本物理学会講演概要集. 秋の分科会 1994 (0) 469-469 1994年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyoj.1994.2.0_469_2  

  190. 29a-YM-3 Fe-Tb, Co-Tb系アモルファス磁性薄膜の磁気円二色性

    中村 哲也, 金 燦旭, 水牧 仁一朗, 渡辺 康裕, 七尾 進

    日本物理学会講演概要集. 年会 49 (0) 511-511 1994年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyog.49.2.0_511_1  

  191. 29a-YG-9 Siのコンプトン・プロファイル

    桜井 吉晴, 田中 良和, 中村 哲也, 七尾 進, 河田 洋, 塩谷 亘弘

    日本物理学会講演概要集. 年会 49 (0) 254-254 1994年

    出版者・発行元:一般社団法人 日本物理学会

    DOI: 10.11316/jpsgaiyog.49.3.0_254_1  

︎全件表示 ︎最初の5件までを表示

講演・口頭発表等 133

  1. X-ray Imaging with Synchrotrons 招待有り

    Tetsuya Nakamura

    2021 IEEE 11th International Conference “Nanomaterials: Applications & Properties” 2021年9月8日

  2. コアリションビームラインの設計と建設の進捗状況 招待有り

    中村 哲也

    第34回日本放射光学会年会・放射光科学合同シンポジウム 2021年1月9日

  3. コアリションコンセプトを推進する次世代放射光ビームライン 招待有り

    第71回コロイドおよび界面化学討論会 2020年9月16日

  4. 硬X線磁気トモグラフィによる極微細粒Nd-Fe-B焼結磁石の三次元磁区観察

    竹内誠, 芳賀僚太, 菊池伸明, 岡本聡, 鈴木基寛, 小林慎太郎, 中村哲也, 中村哲也, 大久保忠勝, 埋橋淳, 宇根康裕

    電気学会研究会資料 2020年

  5. 次世代放射光で進化する材料機能イメージング

    中村哲也

    資源・素材(Web) 2020年

  6. 高周波MnZnフェライトの磁区構造解析

    千葉龍矢, 村井健一, 三角彰太, 大河内拓雄, 中村哲也

    SPring-8/SACLA利用研究成果集(Web) 2020年

  7. 磁気円二色性によるキラル磁性体CrNb<sub>3</sub>S<sub>6</sub>の元素選択磁気測定

    美藤正樹, 美藤正樹, 大隅寛幸, 鶴田一樹, 小谷佳範, 中村哲也, 戸川欣彦, 戸川欣彦, 篠嵜美沙子, 加藤雄介, 加藤雄介, 岸根順一郎, 岸根順一郎, 大江純一郎, 高阪勇輔, 高阪勇輔, 秋光純, 井上克也, 井上克也

    日本物理学会講演概要集(CD-ROM) 2018年3月23日

  8. 軟X線走査型MCD顕微鏡によるSm‐Co系焼結磁石の磁区観察

    加藤涼, 木田潤一郎, 中村哲也, 梶原堅太郎, 隅谷和嗣, 松浦裕, 田村隆治

    日本金属学会講演概要(CD-ROM) 2018年3月5日

  9. Pt/Cr<sub>2</sub>O<sub>3</sub>積層膜における非線形ホール効果とX線MCD測定

    白土優, 青野晃, 森山貴広, 鈴木基寛, 中村哲也, 小野輝男, 中谷亮一

    日本金属学会講演概要(CD-ROM) 2018年3月5日

  10. Microscopic Origin of Interfacial Dzyaloshinskii-Moriya Interaction

    Sanghoon Kim, Kohei Ueda, Gyungchoon Go, Peong-Hwa Jang, Kyung-Jin Lee, Abderrezak Belabbes, Aurelien Manchon, Motohiro Suzuki, Yoshinori Kotani, Tetsuya Nakamura, Kohji Nakamura, Tomohiro Koyama, Daichi Chiba, Kihiro Yamada, Duck-Ho Kim, Takahiro Moriyama, Kab-Jin Kim, Teruo Ono

    2017年4月11日

    詳細を見る 詳細を閉じる

    Chiral spin textures at the interface between ferromagnetic and heavy<br /> nonmagnetic metals, such as Neel-type domain walls and skyrmions, have been<br /> studied intensively because of their great potential for future nanomagnetic<br /> devices. The Dyzaloshinskii-Moriya interaction (DMI) is an essential phenomenon<br /> for the formation of such chiral spin textures. In spite of recent theoretical<br /> progress aiming at understanding the microscopic origin of the DMI, an<br /> experimental investigation unravelling the physics at stake is still required.<br /> Here, we experimentally demonstrate the close correlation of the DMI with the<br /> anisotropy of the orbital magnetic moment and with the magnetic dipole moment<br /> of the ferromagnetic metal. The density functional theory and the tight-binding<br /> model calculations reveal that asymmetric electron occupation in orbitals gives<br /> rise to this correlation.

  11. Nd<sub>2</sub>Fe<sub>14</sub>Bの電子密度分布の温度依存性

    岡崎宏之, 上野若菜, 辻成希, 中村哲也, 中村哲也, 杉本邦久, 河口彰吾, 広沢哲

    日本金属学会講演概要(CD-ROM) 2017年3月1日

  12. XMCD検出によるESR測定法の開拓

    野尻浩之, BAKER Michael, 松澤智, 鳴海康雄, 中村哲也

    SPring-8/SACLA利用研究成果集(Web) 2017年

  13. Nd‐Fe‐B焼結磁石におけるNd<sub>2</sub>Fe<sub>14</sub>Bの電子密度分布解析

    岡崎宏之, 上野若菜, 辻成希, 中村哲也, 中村哲也, 杉本邦久, 河口彰吾, 広沢哲

    日本金属学会講演概要(CD-ROM) 2016年3月9日

  14. 19aAU-10 垂直磁化フェリ磁性GdFeCo薄膜に光誘起される巨大スピン波

    大河内 拓雄, Schneider C. M, 黒田 寛人, Arguelles E. F, 坂上 護, 笠井 秀明, 菅 滋正, 木下 豊彦, 藤原 秀紀, 小嗣 真人, Adam R, 高橋 宏和, 角田 匡清, 塚本 新, 関山 明, 中村 哲也

    日本物理学会講演概要集 2016年

  15. 21pPSA-33 軟X線光電子顕微鏡によるフェリ磁性体GdFeCoのレーザー励起磁化反転機構の組成・温度依存性の研究

    八木 智弘, 大沢 仁志, Schneider Claus M, 関山 明, 菅 滋正, 木下 豊彦, 大河内 拓雄, 藤原 秀紀, 小嗣 真人, Adam Roman, 高橋 宏和, 角田 匡清, 塚本 新, 中村 哲也

    日本物理学会講演概要集 2015年

  16. 7pPSA-26 軟X線光電子顕微鏡によるフェリ磁性体GdFeCoのレーザー励起磁化反転機構の研究(7pPSA 領域3ポスターセッション(スピントロニクス,表面・界面磁性,実験技術,磁性一般),領域3(磁性))

    八木 智弘, 大沢 仁志, Schneider Claus M, 関山 明, 菅 滋正, 木下 豊彦, 大河内 拓雄, 藤原 秀紀, 小嗣 真人, Adam Roman, 高橋 宏和, 角田 匡清, 塚本 新, 中村 哲也

    日本物理学会講演概要集 2014年

  17. 28aKM-6 垂直磁化GdFeCo薄膜の光誘起磁化反転ダイナミクスの補償温度依存性(表面磁性(表面・界面・ナノ粒子),領域3,領域9合同,領域3(磁性,磁気共鳴))

    大河内 拓雄, 大沢 仁志, Schneider Claus M, 菅 滋正, 木下 豊彦, 藤原 秀紀, 小嗣 真人, Adam Roman, 高橋 宏和, 角田 匡清, 塚本 新, 関山 明, 中村 哲也

    日本物理学会講演概要集 2013年

  18. 25pKM-13 強磁場軟X線MCDによるNd-Fe-B焼結磁石の粒界磁気物性(遍歴磁性,領域3(磁性,磁気共鳴))

    中村 哲也, 広沢 哲, 保井 晃, 小谷 佳範, 大河内 拓雄, 鳴海 康雄, 野尻 浩之, 木下 豊彦, 大久保 忠勝, 宝野 和博

    日本物理学会講演概要集 2013年

  19. 25aPS-40 X線磁気円二色性によるL1_0型FeNi規則合金薄膜の磁気異方性評価(領域3ポスターセッション(スピントロニクス・表面・界面磁性・マルチフェロイクス・遍歴磁性・磁性一般),領域3(磁性,磁気共鳴))

    大槻 匠, 白井 正文, 高梨 弘毅, 小嶋 隆幸, 小嗣 真人, 大河内 拓雄, 中村 哲也, 荻原 美沙子, 田代 敬之, 水口 将輝, 三浦 良雄

    日本物理学会講演概要集 2013年

  20. 26pPSB-12 軟X線光電子顕微鏡による垂直磁化GdFeCo薄膜の磁化反転ダイナミクスの観測(領域5ポスターセッション(放射光,光電子分光,発光,非線形,フォトニック結晶),領域5(光物性))

    大河内 拓雄, 大沢 仁志, Schneider Claus M, 菅滋 正, 木下 豊彦, 藤原 秀紀, 小嗣 真人, Adam Roman, 高橋 宏和, 角田 匡清, 塚本 新, 関山 明, 中村 哲也

    日本物理学会講演概要集 2013年

  21. レアメタルフリー酸化物反強磁性体を用いた垂直交換バイアス薄膜の開発

    白土 優, 中谷 亮一, 三俣 千春, 中村 哲也, 木下 豊彦, 鈴木 基寛, 鳴海 康雄, 野尻 浩之

    日本磁気学会研究会資料 = Bulletin of Topical Symposium of the Magnetics Society of Japan 2012年7月19日

  22. 18pPSA-9 レーザー励起磁化反転によるGdFeCo薄膜の磁区形成と逆ファラデー効果(18pPSA 領域3ポスターセッション(スピントロニクス・薄膜・人工格子・表面・スピングラス・磁気共鳴・実験技術・磁性一般),領域3(磁性,磁気共鳴))

    大河内 拓雄, 大沢 仁志, Schncider Claus M, 木下 豊彦, 菅 滋正, 藤原 秀紀, 小嗣 真人, Adam Roman, 高橋 宏和, 角田 匡清, 塚本 新, 関山 明, 中村 哲也

    日本物理学会講演概要集 2012年

  23. 28aHE-4 パルスレーザーを用いた垂直磁化GdFeCo薄膜の光誘起磁化反転(28aHE 領域3,領域9合同 表面・界面磁性,領域9(表面・界面,結晶成長))

    大河内 拓雄, 福島 和亮, 山口 淳一, 磯上 慎二, 中村 哲也, 児玉 謙司, 藤原 秀紀, 菅 滋正, 木下 豊彦, 小嗣 真人, 角田 匡清, 塚本 新, 関山 明, 新井 邦明

    日本物理学会講演概要集 2011年

  24. 23pJB-2 Ag(110)基板上に形成した鉄フタロシアニン二分子膜のスピン状態(23pJB 領域9,領域3合同表面磁性,領域3(磁性,磁気共鳴))

    福嶋 徹, 酒井 真利, 能登 健一, 塚原 規志, 白木 将, 中村 哲也, 木下 豊彦, 高木 紀明, 川合 眞紀

    日本物理学会講演概要集 2011年

  25. 23aTC-5 パルス強磁場によるEuNi_2(Si_<0.18>Ge_<0.82>)_2の軟X線吸収MCD実験の理論解析(23aTC 放射光真空紫外分光・MCD,領域5(光物性))

    小谷 章雄, 和田 裕文, 金道 浩一, 野尻 浩之, 中村 哲也, 鳴海 康雄, 林 美咲, 光田 暁弘, 広野 等子, 児玉 謙司, 森岡 貴之, 木下 豊彦

    日本物理学会講演概要集 2011年

  26. 23aTC-4 パルス強磁場によるEuNi_2(Si_<0.18>Ge_<0.82>)_2の軟X線吸収MCD実験(23aTC 放射光真空紫外分光・MCD,領域5(光物性))

    中村 哲也, 木下 豊彦, 和田 裕文, 金道 浩一, 野尻 浩之, 小谷 章雄, 鳴海 康雄, 林 美咲, 光田 暁弘, 広野 等子, 児玉 謙司, 森岡 貴之, 齋藤 康太, 田添 昂

    日本物理学会講演概要集 2011年

  27. 23pRA-11 Co/Ru多層膜におけるRu誘起磁気分極成分の軟X線MCD測定(23pRA スピントロニクス(スピントルク・電流誘起ダイナミクス・薄膜・微粒子),領域3(磁性,磁気共鳴))

    山岸 隆一郎, 福井 一生, 細糸 信好, 中村 哲也

    日本物理学会講演概要集 2011年

  28. 21pRA-4 パルス強磁場軟X線MCDで見るCo(S,Se)_2のメタ磁性転移(21pRA 遍歴磁性・スピングラス,領域3(磁性,磁気共鳴))

    鳴海 康雄, Hayashi Misaki, 中村 哲也, 野尻 浩之, 児玉 謙司, 広野 等子, 平賀 晴弘, 山田 和芳, 金道 浩一, 木下 豊彦

    日本物理学会講演概要集 2011年

  29. 21aPS-134 30T軟X線MCD測定に向けた強磁場発生技術開発(21aPS 領域3ポスターセッション,領域3(磁性,磁気共鳴))

    鳴海 康雄, Hayashi Misaki, 森岡 貴之, 齋藤 康太, 野尻 浩之, 中村 哲也, 広野 等子, 木下 豊彦, 児玉 謙司, 金道 浩一

    日本物理学会講演概要集 2011年

  30. 28aHE-3 Co/Ru多層膜の非磁性Ru層における誘起磁気分極成分の軟X線MCD測定(28aHE 領域3,領域9合同 表面・界面磁性,領域9(表面・界面,結晶成長))

    山岸 隆一郎, 福井 一生, 細糸 信好, 中村 哲也

    日本物理学会講演概要集 2011年

  31. 28aHE-4 パルスレーザーを用いた垂直磁化GdFeCo薄膜の光誘起磁化反転(28aHE 領域3,領域9合同 表面・界面磁性,領域3(磁性,磁気共鳴))

    大河内 拓雄, 福島 和亮, 山口 淳一, 磯上 慎二, 中村 哲也, 児玉 謙司, 藤原 秀紀, 菅 滋正, 木下 豊彦, 小嗣 真人, 角田 匡清, 塚本 新, 関山 明, 新井 邦明

    日本物理学会講演概要集 2011年

  32. 28aHE-3 Co/Ru多層膜の非磁性Ru層における誘起磁気分極成分の軟X線MCD測定(28aHE 領域3,領域9合同 表面・界面磁性,領域3(磁性,磁気共鳴))

    山岸 隆一郎, 福井 一生, 細糸 信好, 中村 哲也

    日本物理学会講演概要集 2011年

  33. 25aPS-66 30Tパルス強磁場軟X線MCD装置の開発(25aPS-3 領域3ポスターセッション,領域3(磁性,磁気共鳴))

    林 美咲, 森岡 貴之, 鳴海 康雄, 野尻 浩之, 中村 哲也, 広野 等子, 木下 豊彦, 児玉 謙司, 金道 浩一

    日本物理学会講演概要集 2011年

  34. 25aHE-8 パルス強磁場XMCDによるCo(S,Se)_2のメタ磁性転移の観測(25aHE スピングラス・f電子系・遍歴磁性,領域3(磁性,磁気共鳴))

    鳴海 康雄, 木下 豊彦, 中村 哲也, 林 美咲, 野尻 浩之, 児玉 謙司, 広野 等子, 平賀 晴弘, 山田 和芳, 金道 浩一

    日本物理学会講演概要集 2011年

  35. 23pJB-12 円偏光パルスレーザーによるGdFeCo薄膜の高速磁化反転のダイナミクス(23pJB 領域9,領域3合同 表面磁性,領域9(表面・界面,結晶成長))

    大河内 拓雄, 福島 和亮, 山口 淳一, 磯上 慎二, 中村 哲也, 児玉 謙司, 藤原 秀紀, 菅 滋正, 木下 豊彦, 小嗣 真人, 角田 匡清, 塚本 新, 関山 明, 新井 邦明

    日本物理学会講演概要集 2011年

  36. パルスマグネットを用いた強磁場軟X線MCD測定技術の開発

    中村哲也, 鳴海康雄, 広野等子, 児玉謙司, 林美咲, 磯上慎二, 高橋宏和, 角田匡清, 伊東航, 梅津理恵, 金道浩一, 貝沼亮介, 野尻浩之, 木下豊彦

    日本磁気学会学術講演概要集 2010年9月4日

  37. 23pRG-8 パルス強磁場を用いた軟X線MCD測定技術の開発(23pRG 光電子分光・放射光真空紫外分光・MCD・X線発光,領域5(光物性))

    中村 哲也, 梅津 理恵, 金道 浩一, 貝沼 亮介, 野尻 浩之, 木下 豊彦, 鳴海 康雄, 広野 等子, 児玉 謙司, 林 美咲, 磯上 慎二, 高橋 宏和, 角田 匡清, 伊東 航

    日本物理学会講演概要集 2010年

  38. 23pWL-9 NiCoMnInメタ磁性形状記憶合金の元素選択強磁場磁化測定(23pWL 実験技術・磁性一般,領域3(磁性,磁気共鳴))

    鳴海 康雄, 金道 浩一, 木下 豊彦, 中村 哲也, 林 美咲, 野尻 浩之, 児玉 謙司, 広野 等子, 伊東 航, 梅津 理恵, 貝沼 亮介

    日本物理学会講演概要集 2010年

  39. 25pWX-4 Ag(110)基板に展開した鉄フタロシアニン分子の磁気異方性(25pWX 領域9,領域3合同 表面磁性,領域9(表面・界面,結晶成長))

    福嶋 徹, 酒井 真利, 能登 健一, 塚原 規志, 白木 将, 中村 哲也, 木下 豊彦, 高木 紀明, 川合 眞紀

    日本物理学会講演概要集 2010年

  40. 25pWX-4 Ag(110)基板に展開した鉄フタロシアニン分子の磁気異方性(25pWX 領域9,領域3合同 表面磁性,領域3(磁性,磁気共鳴))

    福嶋 徹, 酒井 真利, 能登 健一, 塚原 規志, 白木 将, 中村 哲也, 木下 豊彦, 高木 紀明, 川合 眞紀

    日本物理学会講演概要集 2010年

  41. 25aPS-21 Cu(110)表面に吸着したFeフタロシアニン分子の磁性(25aPS 領域3ポスターセッション,領域3(磁性,磁気共鳴))

    白木 将, 高木 紀明, 川合 真紀, 福嶋 徹, 能登 健一, 酒井 真利, 伊藤 彩夏, 塚原 規志, 中村 哲也, 児玉 謙司, 木下 豊彦

    日本物理学会講演概要集 2010年

  42. 23pWL-7 軟X線分光実験用パルス強磁場システム(23pWL 実験技術・磁性一般,領域3(磁性,磁気共鳴))

    林 美咲, 鳴海 康雄, 野尻 浩之, 中村 哲也, 広野 等子, 木下 豊彦, 児玉 謙司, 金道 浩一

    日本物理学会講演概要集 2010年

  43. 20pGE-2 CaRuO_3のFe置換による強磁性発現におけるRuの磁気状態(20pGE ルテニウム酸化物,領域8(強相関系:高温超伝導,強相関f電子系など))

    水崎 壮一郎, 平岡 望, 小澤 忠, 佐俣 博章, 野呂 良彦, 大西 智弘, 岡田 直哉, 永田 勇二郎, 谷口 貴士, 伊藤 真義, 櫻井 吉晴, 児玉 謙司, 中村 哲也

    日本物理学会講演概要集 2010年

  44. 22pGC-5 X線MCD法で見る逆ペロフスカイト型化合物の磁性状態(22pGC 遍歴磁性・化合物磁性,領域3(磁性,磁気共鳴))

    芝山 隆史, 竹中 康司, 児玉 謙司, 中村 哲也, 木下 豊彦

    日本物理学会講演概要集 2010年

  45. 28pRE-8 硬X線フーリエ変換ホログラフィー法の開発(28pRE 領域10,領域5合同 X線・粒子線(X線),領域10(誘電体,格子欠陥,X線・粒子線,フォノン物性))

    鈴木 基寛, 磯上 慎二, 角田 匡清, 野村 健二, 淡路 直樹, 中村 哲也

    日本物理学会講演概要集 2009年

  46. 27pYE-8 グラファイトインターカレーション超伝導体CaC_6の共鳴光電子分光(グラフェン電子物性(形成と評価),領域7,分子性固体・有機導体)

    岡崎 宏之, 高野 義彦, 冨岡 史明, 竹中 麻美, 豊田 昌宏, 小口 多美夫, 横谷 尚睦, 吉田 力矢, 岩井 啓介, 野網 健吾, 室 隆桂之, 中村 哲也, 脇田 高徳, 村岡 祐治, 平井 正明

    日本物理学会講演概要集 2009年

  47. 27aPS-2 鉄フタロシアニン薄膜のXAS/XMCD測定(領域5ポスターセッション,領域5,光物性)

    白木 将, 川合 真紀, 酒井 真利, 能登 健一, 伊藤 彩夏, 塚原 規志, 児玉 謙司, 中村 哲也, 木下 豊彦, 高木 紀明

    日本物理学会講演概要集 2009年

  48. 26pXA-12 X線磁気二色性,線二色性,及び光電子顕微鏡を用いたNiO(100)における反強磁性磁区構造の詳細観察(新分光法,MCD/MLD,領域5,光物性)

    新井 邦明, 室 隆桂之, 柿崎 明人, 田中 新, 木下 豊彦, 奥田 太一, 小嗣 真人, 福本 恵紀, 大浦 正樹, 仙波 泰徳, 大橋 治彦, 中村 哲也, 松下 智裕

    日本物理学会講演概要集 2009年

  49. 27pPSA-44 パルス強磁場下での軟X線MCD測定技術の開発(領域3ポスターセッション(量子スピン系・フラストレーション系等),領域3,磁性,磁気共鳴)

    中村 哲也, 鳴海 康雄, 広野 等子, 児玉 謙司, 林 美咲, 角田 匡清, 金道 浩一, 野尻 浩之, 木下 豊彦

    日本物理学会講演概要集 2009年

  50. 28pTH-8 逆ペロフスカイト型マンガン窒化物Mn_3CuNのXMCD解析(28pTH 遍歴電子系・f電子系,領域3(磁性,磁気共鳴))

    中村 哲也, 浅野 和子, 竹中 康司, 児玉 謙司, 木下 豊彦

    日本物理学会講演概要集 2009年

  51. 27pPSB-12 Au表面に形成したMnナノワイヤの磁性(27pPSB 領域3ポスターセッション,領域3(磁性,磁気共鳴))

    白木 将, 広瀬 正明, 中村 哲也, 室隆 桂之, 南任 真史, 川合 真紀

    日本物理学会講演概要集 2009年

  52. 22aPS-22 フーリエ変換ホログラフィーによる磁気ドメイン観察の試行(22aPS 領域5ポスターセッション,領域5(光物性))

    中村 哲也, 鈴木 基寛, 淡路 直樹, 土井 修一, 野村 健二, 磯上 慎二, 角田 匡清

    日本物理学会講演概要集 2008年

  53. 20aXA-11 MCD,XRDを用いた隕石由来L1_0型FeNi相の電子スピン状態の研究(20aXA 領域9,領域3合同 表面磁性,領域9(表面・界面,結晶成長))

    小嗣 真人, 水牧 仁一朗, 大坂 恵一, 中村 哲也, 河村 直己, 鈴木 基寛, 石松 直樹, 圓山 裕, 渡辺 義夫

    日本物理学会講演概要集 2008年

  54. 21aWF-4 高分解能光電子分光によるグラファイトインターカレーション超伝導体C_6Caの電子状態(21aWF フラーレン・超伝導,領域7(分子性固体・有機導体))

    岡崎 宏之, 高野 義彦, 竹中 麻美, 豊田 昌宏, 小口 多美夫, 横谷 尚睦, 吉田 力矢, 岩井 啓介, 野網 健悟, 室 隆桂之, 中村 哲也, 村岡 祐治, 平井 正明, 冨岡 史明

    日本物理学会講演概要集 2008年

  55. 21pPSA-14 Fe/NiO(100)界面における交換結合状態(21pPSA 領域3ポスターセッション,領域3(磁性,磁気共鳴))

    新井 邦明, 福本 恵紀, 奥田 太一, 松下 智裕, 中村 哲也, 室 隆桂之, 柿崎 明人, 木下 豊彦

    日本物理学会講演概要集 2008年

  56. 21pQG-13 静磁気的に結合したミクロンサイズ磁気円盤配列における磁気渦コアダイナミクスの観測(21pQG スピントロニクス・微小領域磁性,領域3(磁性,磁気共鳴))

    新井 邦明, 柿崎 明人, 木下 豊彦, 福本 恵紀, 奥田 太一, 中村 哲也, 木村 崇, 松下 智裕, 大沢 仁志, 室隆 桂之, 大谷 義近

    日本物理学会講演概要集 2008年

  57. 20aXA-11 MCD,XRDを用いた隕石由来L1_0型FeNi相の電子スピン状態の研究(20aXA 領域9,領域3合同 表面磁性,領域3(磁性,磁気共鳴))

    小嗣 真人, 水牧 仁一朗, 大坂 恵一, 中村 哲也, 河村 直己, 鈴木 基寛, 石松 直樹, 圓山 裕, 渡辺 義夫

    日本物理学会講演概要集 2008年

  58. 18aTB-2 Fe単原子ワイヤーの電子状態と磁性(領域3,領域9合同 2.表面・界面磁性,領域9,表面・界面,結晶成長)

    南任 真史, 白木 将, 藤澤 英樹, 広瀬 正明, 中村 哲也, 室 隆桂之, 川合 真紀

    日本物理学会講演概要集 2007年

  59. 20aPS-7 Au(788)表面上に構築した3d遷移金属ナノ構造の磁性(ポスターセッション,領域9,表面・界面,結晶成長)

    白木 将, 室 隆桂之, 藤澤 英樹, 古川 雅士, 広瀬 正明, Usman Brian, 南任 真史, 川合 真紀, 中村 哲也, 大沢 仁志

    日本物理学会講演概要集 2007年

  60. 24aTK-10 放射光パルスとフェムト秒レーザーパルス同期による時間分解XMCD-PEEM(光電子分光・MCD,領域5,光物性)

    福本 恵紀, 木下 豊彦, 大沢 仁志, 松下 智裕, 新井 邦明, 中村 哲也, 室 隆桂之, 木村 崇, 大谷 義近, 柿崎 明人

    日本物理学会講演概要集 2007年

  61. 22aXK-2 Au(788)表面上に構築した3d遷移金属ナノ構造の磁性(表面磁性,表面界面電子物性,領域9,表面・界面,結晶成長)

    白木 将, 藤澤 英樹, 広瀬 正明, Usman Brianto, 南任 真史, 川合 真紀, 中村 哲也, 大沢 仁志, 室 隆桂之

    日本物理学会講演概要集 2007年

  62. 21pPSB-75 Pdナノ粒子のX線磁気円二色性実験(領域3ポスターセッション(フラストレーション,磁気共鳴,実験技術,微小領域),領域3,磁性,磁気共鳴)

    大場 洋次郎, 岡本 啓明, 佐藤 徹哉, 中村 哲也, 大沢 仁志, 室 隆桂之, 篠原 武尚, 鈴木 淳市

    日本物理学会講演概要集 2007年

  63. 22aPS-72 反強磁性NiO表面上のFe超薄膜の磁化特性(領域3ポスターセッション(薄膜・人工格子,スピングラス,量子スピン系),領域3,磁性,磁気共鳴)

    福木 恵紀, 柿崎 明人, 木下 豊彦, 新井 邦明, 奥田 太一, 松下 智裕, 郭 方准, 大浦 正樹, 竹内 智之, 中村 哲也, 室 隆桂之

    日本物理学会講演概要集 2007年

  64. 24pXA-1 高濃度ホウ素ドープダイヤモンドの軟X線光電子分光(ダイヤモンド・Si超伝導,領域8,強相関係:高温超伝導,強相関f電子系など)

    岡崎 宏之, 石井 聡, 入山 慎吾, 川原田 洋, 横谷 尚睦, 室 隆桂之, 中村 哲也, 松下 智裕, 脇田 高徳, 村岡 祐治, 平井 正明, 高野 義彦

    日本物理学会講演概要集 2007年

  65. 24pxA-2 軟X線光電子分光によるn型リンドープダイヤモンドの電子構造の研究(ダイヤモンド・Si超伝導,領域8,強相関係:高温超伝導,強相関f電子系など)

    岡崎 宏之, 山崎 聡, 高野 義彦, 石井 聡, 小口 多美夫, 横谷 尚睦, 室 隆桂之, 中村 哲也, 松下 智裕, 脇田 高徳, 村岡 祐治, 平井 正明, 加藤 宙光

    日本物理学会講演概要集 2007年

  66. 18aTB-2 Fe単原子ワイヤーの電子状態と磁性(18aTB 領域3,領域9合同 2.表面・界面磁性,領域3(磁性,磁気共鳴))

    南任 真史, 白木 将, 藤澤 英樹, 広瀬 正明, 中村 哲也, 室 隆桂之, 川合 真紀

    日本物理学会講演概要集 2007年

  67. 19aWF-5 高濃度ボロンドープダイヤモンドの軟X線角度分解光電子分光(19aWF ドープダイヤモンド,領域8(強相関系:高温超伝導,強相関f電子系など))

    横谷 尚睦, 小口 多美夫, 岡崎 宏之, 中村 哲也, 室 隆桂之, 松下 智裕, 高野 義彦, 長尾 雅則, 竹之内 智大, 川原田 洋

    日本物理学会講演概要集 2007年

  68. 19pWF-6 Ca_<1.5>Sr_<0.5>RuO_4の軟X線角度分解光電子分光によるバルクフェルミ面・スペクトル形状(19pWF Ru系,領域8(強相関系:高温超伝導,強相関f電子系など))

    漆間 正行, 菅 滋正, 関山 明, 藤原 秀紀, 矢野 正雄, 藤田 浩史, 今田 真, 室 隆桂之, 中村 哲也, 前野 悦輝

    日本物理学会講演概要集 2007年

  69. Mn_3Ir反強磁性合金による巨大交換バイアス

    角田 匡清, 三俣 千春, 中村 哲也, 高橋 研

    日本応用磁気学会研究会資料 2006年10月18日

  70. 23aPS-42 Ce(Fe_<0.8>Co_<0.2>)_2の内殻吸収磁気円二色性(23aPS 領域3ポスターセッション(磁性),領域3(磁性,磁気共鳴))

    恒川 雅典, 室 隆桂之, 和田 裕文, 今田 真, 松本 惇, 山崎 篤志, 藤原 秀紀, 菅 滋正, Schmid Benjamin, 東道 啓聡, 中村 哲也

    日本物理学会講演概要集 2006年

  71. 26aYH-3 Au(788)表面上に形成した3d遷移金属ナノ構造の磁性(26aYH 領域3,領域9合同 表面・界面磁性,領域9(表面・界面,結晶成長))

    高山 英俊, 藤澤 英樹, 白木 将, 広瀬 正明, 南任 真史, 川合 真紀, 中村 哲也, 室 隆桂之

    日本物理学会講演概要集 2006年

  72. 27pTE-9 Fe_<2-x>Ti_xO_3固溶体中のTi^<4+>イオンの磁気分極(27pTE 磁気共鳴一般・実験技術開発・酸化物磁性,領域3(磁性,磁気共鳴))

    藤井 達生, 山下 美樹, 藤森 伸一, 齋藤 祐児, 中村 哲也, 小林 啓介, 高田 潤

    日本物理学会講演概要集 2006年

  73. 27aTD-11 ホウ素ドープCVDダイヤモンド薄膜の角度分解光電子分光(27aTD ホウ化物,炭化物(超伝導),領域8(強相関系:高温超伝導,強相関f電子系など))

    横谷 尚睦, 松下 智裕, 高田 恭孝, 徳島 高, 辛 埴, 高野 義彦, 長尾 雅則, 竹之内 智大, 川原田 洋, 小口 多美夫, 岡崎 宏之, 川田 純也, 元光 邦彦, 中村 仁, 山田 修義, 中村 哲也, 室隆 桂之, 為則 雄祐

    日本物理学会講演概要集 2006年

  74. 26aYH-3 Au(788)表面上に形成した3d遷移金属ナノ構造の磁性(26aYH 領域3,領域9合同 表面・界面磁性,領域3(磁性,磁気共鳴))

    高山 英俊, 藤澤 英樹, 白木 将, 広瀬 正明, 南任 真史, 川合 真紀, 中村 哲也, 室 隆桂之

    日本物理学会講演概要集 2006年

  75. 27pPSA-33 Mn_<2.97>Co_<0.03>GaCの磁気円二色性および光電子分光(27pPSA 領域3ポスターセッション 薄膜・人工格子磁性,表面・界面磁性,微小領域磁性,遍歴磁性,化合物磁性,f電子系磁性磁性,領域3(磁性,磁気共鳴))

    松本 惇, 室 隆桂之, 菅 滋正, 今田 真, 恒川 雅典, 山崎 篤志, 東道 啓聡, 服部 芳郎, Schmid Benjamin, 和田 裕文, 中村 哲也

    日本物理学会講演概要集 2006年

  76. 27pPSA-32 MnFeP_<0.78>Ge_<0.22>のL_<2,3>内殻吸収磁気円二色性(27pPSA 領域3ポスターセッション 薄膜・人工格子磁性,表面・界面磁性,微小領域磁性,遍歴磁性,化合物磁性,f電子系磁性磁性,領域3(磁性,磁気共鳴))

    恒川 雅典, Bruck Ekkes, 菅 滋正, 小山 佳一, 今田 真, 松本 惇, 山崎 篤志, 八窪 裕人, Schmid Benjamin, 東道 啓聡, 服部 芳郎, 中村 哲也

    日本物理学会講演概要集 2006年

  77. 20pXH-6 軟X線MCDによるナノ粒子、および、ナノワイヤーの高感度磁化解析(領域3,領域9合同シンポジウム,主題 : ナノスケールで発現する金属磁性,領域3(磁性,磁気共鳴))

    中村 哲也, 木下 豊彦, 小林 啓介, 藤澤 英樹, 白木 将, 山田 貴之, 室 隆桂之, 松下 智裕, 広野 等子, 川合 真紀, 七尾 進

    日本物理学会講演概要集 2005年

  78. 19pYK-5 Al-Mn-Fe-Ge準結晶合金の軟X線MCD(準結晶(構造,電子物性,表面,空孔),領域6(金属,超低温,超伝導・密度波))

    山田 貴之, 七尾 進, 中村 哲也, 横山 嘉彦, 鎌倉 望, 室 隆桂之, 松下 智裕, 広野 等子, 小林 啓介, 渡辺 康裕

    日本物理学会講演概要集 2005年

  79. 20pPSA-4 Cr_xTi_<1-x>N/MgOの電子状態(領域5ポスターセッション,領域5(光物性))

    崔 芸濤, 斎藤 祐児, 竹田 幸治, 小山 邦彦, 宮木 雄史, 田中 和馬, 犬丸 啓, 山中 昭司, 木村 昭夫, 宮本 幸治, 坂本 和昭, 謝 天, 喬 山, 島田 賢也, 谷口 雅樹, 中村 哲也

    日本物理学会講演概要集 2005年

  80. 24aPS-169 Au(788)微傾斜表面上におけるFeナノ構造の磁性(表面・界面, 結晶成長,領域9(表面・界面, 結晶成長))

    藤澤 英樹, 白木 将, 伊藤 信太郎, 古川 雅士, 南任 真史, 川合 真紀, 室 隆桂之, 中村 哲也

    日本物理学会講演概要集 2005年

  81. 26pXP-5 Coクラスター/Si(111)のXMCDスペクトル(領域5, 領域3, 領域8合同招待講演,領域5(光物性))

    望戸 力, 謝 天, 喬 山, 木村 昭夫, 生天目 博文, 谷口 雅樹, 中村 哲也, 斎藤 祐児, 竹田 幸治

    日本物理学会講演概要集 2005年

  82. 26pXP-4 強磁性形状記憶合金Ni_2Mn_<0.5>Fe_<0.5>Gaの軟X線磁気円二色性(領域5, 領域3, 領域8合同招待講演,領域5(光物性))

    八窪 裕人, 今田 真, 渡邊 智健, Schmid Benjamin, 鹿又 武, 中村 哲也, 室 隆桂之, 菅 滋正

    日本物理学会講演概要集 2005年

  83. 24aWA-8 硬x線光電子分光によるボロンドープ超伝導ダイヤモンド薄膜の電子状態(ホウ素・炭素系(超伝導・四極子),領域8(強相関系:高温超伝導,強相関f電子系など))

    横谷 尚睦, 長尾 雅則, 坂口 勲, 立木 実, 羽多野 毅, 竹之内 智大, 小林 健作, 梅沢 仁, 原田 洋, 池永 英司, 小畠 雅明, 小林 啓介, 竹内 晃久, 淡路 晃弘, 中村 哲也, 室 隆桂之, 高野 義彦

    日本物理学会講演概要集 2005年

  84. 26pXN-15 軟X線MCDによるAl-Mn-Fe-Ge準結晶合金の元素別磁化解析(フラストレーション系(三角格子・カゴメ格子),スピングラス・ランダム系,領域3(磁性,磁気共鳴))

    中村 哲也, 横山 嘉彦, 鎌倉 望, 室 隆桂之, 松下 智裕, 広野 等子, 小林 啓介

    日本物理学会講演概要集 2005年

  85. 24aXN-6 Au及びPtに挟まれたFe1原子層の軟X線磁気円二色性の温度変化(薄膜・人工格子磁性,表面・界面磁性,トンネル分光,領域3(磁性,磁気共鳴))

    渡辺 智健, 今田 真, 山崎 篤志, 税田 哲朗, 中村 哲也, 室 隆桂之, 嶋 敏之, 高梨 弘毅, 菅 滋正

    日本物理学会講演概要集 2005年

  86. SPring-8 BL25SU における軟X線元素選択磁化測定の現状

    中村 哲也, 室隆 桂之, 松下 智弘, 小林 啓介

    日本応用磁気学会学術講演概要集 = Digest of ... annual conference on magnetics in Japan 2004年9月21日

  87. 12aPS-74 軟 X 線による軌道 Ferri 磁性体 CoMnO_3 の電子状態の研究(磁性・磁気共鳴, 領域 3)

    水牧 仁一朗, 佐藤 博彦, 渡辺 峰旨, 河村 直己, 中村 哲也, 宮川 隼人, 安居院 あかね

    日本物理学会講演概要集 2004年

  88. 30aXD-10 YB_2C_2の超伝導における同位元素効果(四極子秩序,関連物質)(領域8)

    吉川 明子, 中村 哲也, 鴫海 康雄, 勝又 紘一

    日本物理学会講演概要集 2004年

  89. 27aPS-107 SPring-8 BL25SUにおける軟X線MCDによる元素選択磁化解析(領域3ポスターセッション : 希土類合金,化合物磁性,薄膜・人工格子,スピングラス,フラストレーション,量子スピン系,実験技術開発等)(領域3)

    中村 哲也, 室 隆桂之, 郭 方准, 松下 智裕, 脇田 高徳, 大橋 治彦, 小林 啓介

    日本物理学会講演概要集 2004年

  90. 12pWB-14 固体酸素における磁場誘起体積膨張(化合物磁性, 磁性半導体・絶縁体, 実験技術開発, 磁気共鳴一般, 磁性一般, 領域 3)

    木村 尚次郎, 北村 英男, 勝又 紘一, Staub U, 鳴海 康雄, 田中 良和, 下村 晋, 中村 哲也, Lovesey Stephen W, 石川 哲也

    日本物理学会講演概要集 2004年

  91. 13pPSA-2 内殻励起磁気円二色性による Ce 化合物の磁性研究(領域 5)

    中村 聡, 中村 哲也, 室隆 桂之, 宮原 恒あき, 石井 広義, 高山 泰弘, 吉田 徹夫, 佐々木 直也, 佐藤 英行, 菊池 大輔, 塩澤 秀次

    日本物理学会講演概要集 2004年

  92. 28pYE-9 RbMnFe(CN)_6 の X 線発光、吸収分光による光誘起スピン状態転移観察 2

    大沢 仁志, 高野 剛次, 七尾 進, 五十棲 泰人, 所 裕子, 大越 慎一, 橋本 和仁, 野沢 俊介, 岩住 俊明, 中村 哲也, 小路 博信, 平井 栄樹

    日本物理学会講演概要集 2003年

  93. 31aXG-2 CuGeO_3 の磁場中 X 線散乱

    鳴海 康雄, 原 徹, 田中 降次, 玉作 賢治, 矢橋 牧名, 後藤 俊治, 大橋 治彦, 竹下 邦和, 大端 通, 松下 智裕, 備前 輝彦, 勝又 紘一, 松田 雅昌, 田畑 吉計, 木村 尚次郎, 田中 良和, 中村 哲也, 下村 晋, 石川 哲也, 北村 英男

    日本物理学会講演概要集 2003年

  94. 22pPSA-2 希土類価数揺動物質の局所帯磁率

    塩澤 秀次, 室 隆桂之, 斎藤 祐児, 海老原 孝雄, 宮原 恒〓, 中村 聡, 大坪 英雄, 高山 泰弘, 石井 広義, 菅原 仁, 佐藤 英行, 中村 哲也

    日本物理学会講演概要集 2003年

  95. 21aWG-10 X 線共鳴散乱による HoB_2C_2 の多重極子の観察

    田中 良和, 田畑 吉計, 中村 哲也, 鳴海 康雄, 勝又 紘一, 玉作 賢治, 石川 哲也

    日本物理学会講演概要集 2003年

  96. 22aWA-5 ポリマー被覆金ナノ微粒子の XMCD

    山本 良之, 三浦 尊裕, 鈴木 基寛, 河村 直己, 宮川 勇人, 中村 哲也, 小林 啓介, 堀 秀信

    日本物理学会講演概要集 2003年

  97. 30aXC-8 多重散乱理論によるTb-Co系合金のCo K-edge XMCD解析

    永松 伸一, 藤川 高志, 中村 哲也

    日本物理学会講演概要集 2001年

  98. 28aXA-1 希上類アモルファス合金の希土類L吸収端における多電子励起磁気円二色性

    中村 哲也, 渡辺 康裕, 田村 純平, 平井 栄樹, 七尾 進, 水牧 仁一朗

    日本物理学会講演概要集 2001年

  99. 18aPS-42 鉄系スピンクロスオーバ錯体のX線発光、吸収分光によるスピン状態転移観察 2

    大沢 仁志, 五十棲 泰人, 七尾 進, 岩住 俊明, 小路 博信, 平井 栄樹, 中村 哲也, 小川 佳宏, 石川 忠彦, 腰原 伸也, 片野 林太郎

    日本物理学会講演概要集 2001年

  100. 17aRG-2 RAl_2, RFe_2のR L_<2,3>-edgeにおけるXMCD

    中村 哲也, 水牧 仁一朗, 河村 直己, 宮川 勇人, 渡辺 康裕, 七尾 進, 安達 弘通

    日本物理学会講演概要集 2001年

  101. 17pZA-3 軟X線MCDよるSmFe_2の磁気モーメント評価

    宮川 勇人, 中村 哲也, 渡辺 康裕, 水牧 仁一郎, 室隆 桂之, 七尾 進

    日本物理学会講演概要集 2001年

  102. 24pPSB-60 CeFe_2の磁気EXAFSによる磁気構造の決定

    水牧 仁一朗, 中村 哲也, 宮川 勇人, 吉井 資次, 鈴木 基寛, 河村 直巳, 七尾 進

    日本物理学会講演概要集 2000年

  103. 23aXC-4 垂直配置X線発光磁気円二色性スペクトルの測定

    岩住 俊明, 小路 博信, 宮川 勇人, 中村 哲也, 七尾 准, 片野 林太郎, 五十棲 泰人

    日本物理学会講演概要集 2000年

  104. 22pXC-5 SmL_<II> L_<III>吸収端における2p4f四重極遷移の発光MCD

    中村 哲也, 岩住 俊明, 小路 博信, 渡辺 康裕, 水牧 仁一朗, 岸本 俊二, 片野 林太郎, 五十棲 泰人, 七尾 進

    日本物理学会講演概要集 2000年

  105. 25aW-8 Ni(110)における酸素吸着と初期酸化過程

    渡辺 一寿, 中村 哲也, 井口 玉美, 西山 雅之, 池田 佳子, 石井 康博, 柴田 真希子, 福谷 博仁

    日本物理学会講演概要集 2000年

  106. 25aQ-3 準結晶のX線発光分光測定

    渡辺 康裕, 中村 哲也, 小路 博信, 岩住 俊明, 水牧 仁一朗, 岸本 俊二, 片野 林太郎, 五十棲 泰人, 七尾 道

    日本物理学会講演概要集 2000年

  107. 22pM-15 Si単結晶のX線共鳴非弾性散乱 : 偏光相関・方位角依存性

    岩住 俊明, 小路 博信, 中村 哲也, 七尾 進, 岸本 俊二, 片野 林太郎, 五十棲 泰人

    日本物理学会講演概要集 2000年

  108. 22pM-5 Sm Lα_<1,2>の発光MCD

    中村 哲也, 岩住 俊明, 小路 博信, 渡辺 康裕, 水牧 仁一朗, 岸本 俊二, 片野 林太郎, 五十棲 泰人, 七尾 進

    日本物理学会講演概要集 2000年

  109. 22aE-4 DyCo_5のX線磁気コンプトン散乱

    宮川 勇人, 渡辺 康裕, 平岡 望, 小泉 昭久, 坂井 信彦, 水牧 仁一郎, 桜井 吉晴, 中村 哲也, 七尾 進

    日本物理学会講演概要集 2000年

  110. 28p-ZH-8 X線共鳴非弾性散乱による遷移金属化合物の電子構造研究

    小路 博信, 小林 憲司, 中村 哲也, 岩住 俊明, 片野 林太郎, 五十棲 泰人, 岸本 俊二, 七尾 進

    日本物理学会講演概要集 1999年

  111. 28a-ZH-5 純コバルトにおけるCo Kα_<1, 2>の発光MCD

    中村 哲也, 岩住 俊明, 小路 博信, 岸本 俊二, 片野 林太郎, 五十僂 泰人, 七尾 進

    日本物理学会講演概要集 1999年

  112. 25pYC-14 発光MCDによるX線領域でのCoster-Kronig過程の検証

    中村 哲也, 岩住 俊明, 小路 博信, 岸本 俊二, 片野 林太郎, 五十棲 素人, 七尾 進

    日本物理学会講演概要集 1999年

  113. 25pYC-5 Mn化合物のX線共鳴非弾性散乱

    小路 博信, 岩住 俊明, 小林 憲司, 中村 哲也, 岸本 俊二, 片野 林太郎, 五十棲 素人, 七尾 進

    日本物理学会講演概要集 1999年

  114. 27a-K-11 X線磁気回折によるhcp-CoのLS分離

    伊藤 正久, 田中 良和, 松本 紳, 和光 信也, 春本 将彦, 宮川 勇人, 中村 哲也, 渡辺 康裕, 七尾 進, 安達 弘通, 森 丈晴, 河田 洋

    日本物理学会講演概要集 1998年

  115. 26a-YP-14 アモルファスCo-GdのGdL吸収・発光MCDの組成依存性

    中村 哲也, 七尾 進, 小路 博信, 岩住 俊明, 小林 憲司, 岸本 俊二, 片野 林太郎, 五十棲 泰人, 水牧 仁一朗, 渡辺 康裕

    日本物理学会講演概要集 1998年

  116. 26a-YP-13 強磁性Gd化合物のGdLα_<1.2>,β_1,β_<2.15>,γ_1発光MCD

    中村 哲也, 岩住 俊明, 小路 博信, 小林 憲司, 岸本 俊二, 片野 林太郎, 五十棲 泰人, 七尾 進

    日本物理学会講演概要集 1998年

  117. 26p-YK-5 SmFe_2のX線磁気ブラッグ散乱

    宮川 勇人, 富永 照男, 中村 哲也, 渡辺 康裕, 安達 弘通, 河田 洋, 伊藤 正久, 七尾 進

    日本物理学会講演概要集 1998年

  118. 31a-A-6 Fe, Co, Niと3d遷移金属化合物のXMCD測定と理論解析

    水牧 仁一朗, 藤川 高志, 畑田 圭介, 永松 伸一, 中村 哲也, 渡辺 康裕, 七尾 進

    日本物理学会講演概要集 1997年

  119. 30p-WE-9 2次元Deposition model におけるスケーリング則

    中村 哲也, 溝上 伸也, 大橋 弘忠

    日本物理学会講演概要集 1997年

  120. 7p-X-7 白色X線磁気回折によるhcp-TbのLS分離

    伊藤 正久, 藤井 俊行, 春本 将彦, 中村 哲也, 森 丈晴, 村上 洋一, 河田 洋

    日本物理学会講演概要集 1997年

  121. 7p-X-6 蛍光分光法による多電子励起のX線磁気円二色性

    中村 哲也, 七尾 進, 岩住 俊明, 小林 憲司, 岸本 俊二, 大沢 大輔, 片野 林太郎, 五十棲 泰人

    日本物理学会講演概要集 1997年

  122. 5p-G-14 X線共鳴ラマン散乱における磁気的共鳴効果

    岩住 俊明, 小林 憲司, 岸本 俊二, 中村 哲也, 七尾 進, 大沢 大輔, 片野 林太郎, 五十棲 泰人

    日本物理学会講演概要集 1997年

  123. 5p-G-13 希土類金属L_3-吸収端の共鳴発光分光

    小林 憲司, 岩住 俊明, 岸本 俊二, 中村 哲也, 七尾 進, 大沢 大輔, 片野 林太郎, 五十棲 泰人, 圓山 裕

    日本物理学会講演概要集 1997年

  124. 3a-W-8 白色X線磁気回折によるFeの磁気形状因子II

    伊藤 正久, 松本 紳, 和光 信也, 藤井 俊行, 橋本 英生, 中村 哲也, 河田 洋, 森 丈晴, 坂井 信彦, 伊藤 文武, 七尾 進

    日本物理学会講演概要集. 年会 1996年

  125. 1a-Z-11 DyFe_2のMagnetic EXAFS

    中村 哲也, 水牧 仁一朗, 渡辺 康裕, 木村 仁, 東 芳, 吉見 学, 七尾 進

    日本物理学会講演概要集. 年会 1996年

  126. 1a-Z-9 遷移金属ボロン化合物のMCD

    水牧 仁一朗, 中村 哲也, 木村 仁, 渡辺 康裕, 七尾 進

    日本物理学会講演概要集. 年会 1996年

  127. 白色X線磁気回折による強磁性Coの磁気形状因子

    伊藤 正久, 松本 紳, 和光 信也, 田中 良和, 藤井 俊行, 春本 将彦, 中村 哲也, 橋本 英生, 森 丈晴, 村上 洋一, 河田 洋

    日本物理学会講演概要集. 秋の分科会 1996年

  128. X線磁気回折によるFeの磁気形状因子の異方性

    伊藤 正久, 七尾 進, 松本 紳, 和光 信也, 藤井 俊行, 春本 将彦, 橋本 英生, 中村 哲也, 河田 洋, 森 丈晴, 坂井 信彦, 伊藤 文武

    日本物理学会講演概要集. 秋の分科会 1996年

  129. La_<1-x>Sr_xCoO_3の金属-絶縁体相転移によるMCDの変化

    水牧 仁一朗, 伊藤 正行, 中村 哲也, 吉見 学, 渡辺 康裕, 七尾 進

    日本物理学会講演概要集. 秋の分科会 1996年

  130. 27p-W-13 Fe_4NのMCD

    水牧 仁一郎, 中村 哲也, 木村 仁, 渡辺 康裕, 七尾 進

    日本物理学会講演概要集. 秋の分科会 1995年

  131. 29a-YG-9 Siのコンプトン・プロファイル

    桜井 吉晴, 田中 良和, 中村 哲也, 七尾 進, 河田 洋, 塩谷 亘弘

    日本物理学会講演概要集. 年会 1994年

  132. 29a-YM-3 Fe-Tb, Co-Tb系アモルファス磁性薄膜の磁気円二色性

    中村 哲也, 金 燦旭, 水牧 仁一朗, 渡辺 康裕, 七尾 進

    日本物理学会講演概要集. 年会 1994年

  133. 5a-X-1 TM-REアモルファス磁性薄膜の硬X線磁気吸収

    中村 哲也, 水牧 仁一朗, 賀茂 尚広, 渡辺 康裕, 七尾 進

    日本物理学会講演概要集. 秋の分科会 1994年

︎全件表示 ︎最初の5件までを表示

共同研究・競争的資金等の研究課題 14

  1. 自由度拡張がもたらす未踏反応場を利用した窒化物半導体結晶成長の学理構築

    福山 博之, 大塚 誠, 中村 哲也

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research

    研究種目:Grant-in-Aid for Scientific Research (A)

    研究機関:Tohoku University

    2021年4月5日 ~ 2026年3月31日

  2. 磁性材料研究拠点 競争的資金

    広沢 哲

    提供機関:Ministry of Education, Culture, Sports, Science and Technology

    制度名:Element Strategy Initiative

    2012年6月 ~ 2022年3月

  3. 永久磁石の微細組織とその局所磁気特性の解析による高保磁力化の指針構築 競争的資金

    中村 哲也

    提供機関:Japan Science and Technology Agency

    制度名:Collaborative Research Based on Industrial Demand

    2016年10月 ~ 2021年3月

  4. 放射光によるナノ磁化ダイナミクス可視化科学の構築

    中村 哲也, 小谷 佳範, 野村 光, 岡本 聡, 菊池 伸明

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)

    研究種目:Grant-in-Aid for Scientific Research (A)

    研究機関:Japan Synchrotron Radiation Research Institute

    2015年4月1日 ~ 2018年3月31日

    詳細を見る 詳細を閉じる

    本研究では、放射光ナノ集光ビームによるX線磁気円二色性(XMCD)測定技術の開発を行った。Co/Ni多層膜を試料とした時分割測定により、約100 nmの微小領域に対する磁化ダイナミクスをXMCD信号変化として検出することに成功した。また、さらに高度なナノ磁化検出技術への挑戦として、軟X線ナノビーム走査プローブ顕微鏡(SR-SPM)を開発した。放射光SPMの励起光源として軟X線集光ビーム生成し、SPM探針直下の試料位置に照射する特徴を有する。従来技術に比べ、SPM探針直下に約1000倍の密度の軟X線ビームを照射可能である。本装置を用い、パーマロイ磁気ドットのXMCD観察に成功した。

  5. 超強磁場中性子・XMCDによる量子磁気偏極相の解明

    野尻 浩之, 鳴海 康雄, 桑原 慶太郎, 中村 哲也, 中島 健次, 大山 研司

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (S)

    研究種目:Grant-in-Aid for Scientific Research (S)

    研究機関:Tohoku University

    2011年4月1日 ~ 2016年3月31日

    詳細を見る 詳細を閉じる

    本研究では、磁場で誘起される量子相転移の研究のために、超低還元温度における強磁場中性子回折、X線分光・回折実験を実現し、磁性体、誘電体、錯体、超伝導体などへ展開した。この結果、磁場誘起量子相について、これまでの手法では得られなかった直接的な秩序変数や電子状態の観測が可能になり、未解明に残された様々な問題に解決がもたらされた。さらに、自由電子レーザーを利用し、電子相転移を捉えるなど、新しいパラダイムへシフトを導き、分光、テラヘルツ科学さらには基礎物理分野にも波及効果をもたらした。これらの結果は、我々が先導する強磁場量子ビーム科学分野の優位性の確保と物質科学の発展に大きく貢献するものである。

  6. 40T超強磁場・軟X線磁気円二色性による電気磁気効果の微視的解明

    鳴海 康雄, 中村 哲也

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    研究種目:Grant-in-Aid for Scientific Research (B)

    研究機関:Tohoku University

    2011年4月1日 ~ 2014年3月31日

    詳細を見る 詳細を閉じる

    電気磁気効果をつかさどる磁性の微視的なメカニズムの解明を目的として、40テスラパルス強磁場と軟X線吸収分光測定を組み合わせた、40T超強磁場・軟X線磁気円二色性測定装置を世界で初めて開発した。この装置を、電気磁気効果を示すマルチフェロイック物質に応用し、LuFe2O4の混合原子価状態にある2価Feと3価Feの価数選択磁化過程の観測、CuFeO2のFeイオンにおけるスピンと軌道磁気モーメントの分離評価、TbMnO3のTbおよびMnの元素別磁気解析を行った。

  7. パルス強磁場XMCDによる元素選択磁化測定技術の開発

    中村 哲也, 鳴海 康雄

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    研究種目:Grant-in-Aid for Scientific Research (B)

    研究機関:Japan Synchrotron Radiation Research Institute

    2009年 ~ 2011年

    詳細を見る 詳細を閉じる

    パルス強磁場中で軟X線MCDを測定する技術開発に世界で初めて成功した。従来の軟X線MCD実験で利用できる磁場は超伝導マグネットによる最大10 Tであったが、本研究によりパルスマグネットを用いた30 Tの強磁場下測定を実現し、当初の研究目標(20 T)以上の結果を達した。本測定技術により、強磁場中における合金や化合物の磁化を、その物質に含まれる磁性元素毎に区別して評価することが可能となり、磁場誘起価数転移磁性体、メタ磁性体、希土類永久磁石、交換バイアス薄膜などの磁性研究に幅広く応用されている。

  8. 界面誘起非補償反強磁性スピンの解明・制御による高性能交換磁気異方性材料の開発

    角田 匡清, 中村 哲也, 三俣 千春, 高橋 宏和

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    研究種目:Grant-in-Aid for Scientific Research (B)

    研究機関:Tohoku University

    2008年 ~ 2010年

    詳細を見る 詳細を閉じる

    Mn^<74> Ir^<26>/Co_<100-x> Fe_x積層膜の交換磁気異方性の大きさと界面誘起非補償反強磁性スピンとの相関を見出した。交換磁気異方性の大きさはx=25at.%で最大となり、非補償反強磁性スピンを表すMnのX線磁気円二色性(XMCD)は負号ならびに大きさが組成xに対して系統的に変化した。両者の間には直線的相関があり、両者を結びつける隠されたパラメータは界面における交換結合であり、それが強磁性層組成に対して変化するものと考えられた。上記知見に基づき、大きなMn-XMCDを誘導する強磁性層を形成すべく極薄のCo-Fe層をL1_2-Mn_3Ir/Co_<65> Fe_<35> 積層膜の界面に挿入することで1. 2erg/cm^2を超える大きな交換磁気異方性材料の開発に成功した。

  9. 軟X線ダイナミクス計測のための高速APD検出器の開発

    岡田 京子, 中村 哲也

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)

    研究種目:Grant-in-Aid for Scientific Research (C)

    研究機関:Japan Synchrotron Radiation Research Institute

    2008年 ~ 2010年

    詳細を見る 詳細を閉じる

    軟X線を高精度・高速・広ダイナミックレンジでエネルギー分解型フォトンカウンティングする、小型の軟X線用高速APD測定器システムの開発を行った。軟X線領域での測定器システムの開発に存在する様々な技術的バリアを克服した、小型の軟X線用高速APD測定器システムの開発を行ない、目標とする性能を達成した。さらに、測定素子を、検出器としての理解と共に、物性的・材料学的にも理解した上で改良する事により、この測定器システムの特性と軟X線磁気円二色性(XMCD)を組み合わせて、スピントロニクス材料に含まれる特定元素の磁気情報を選択的に、かつ定量的に探ることができることを明らかにした。

  10. 時間分解光電子顕微鏡による超高速磁気応答現象の観測

    木下 豊彦, 室 隆桂之, 大河内 拓雄, 小嗣 真人, 大谷 義近, 奥田 太一, 小林 啓介, 松下 智裕, 郭 方准, 大沢 仁志, 中村 哲也, 福本 恵紀, 新井 邦明, 木村 崇, 松井 真二, 春山 雄一

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (S)

    研究種目:Grant-in-Aid for Scientific Research (S)

    研究機関:Japan Synchrotron Radiation Research Institute

    2006年 ~ 2010年

    詳細を見る 詳細を閉じる

    磁気円2色性を利用した放射光光電子顕微鏡において実現していた磁気イメージング観察をさらに発展させ、ポンプ&プローブ観察手法と組み合わせ、磁気応答のサブナノ秒領域のダイナミクスの実空間観察に成功した。微小磁性ドットの磁場パルスに対する応答を観測し、さらに、ドットが近接して配置されている場合の相互作用に関しても観測に成功した。磁場パルスのみならず、電場パルス、光パルスなどの外場を与えたときの応答ダイナミクスの可視化も実現した。

  11. 放射光軟X線を用いた元素選択磁化測定による磁性研究の新展開

    中村 哲也

    2005年 ~ 2007年

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    本研究はSPring-8BL25SUに設置した電磁石軟X線MCD装置に本補助金にて追加整備した蛍光収量法、および、透過法によるMCD測定機能を用いて進められた.実験装置の高度化を伴うMCDの手法開発を進めることにより、従来の磁気測定手法では成し得なかった新しい切りロで新規性の高い磁性材料の磁気特性について研究を行った.H19年度の装置高度化として、軟X線CCDを利用した蛍光収量法によるMCD測定を可能にした(SPring-8実験課題2007A1931).一方、東北大(角田准教授)と進めてきた巨大交換磁気異方性を有するMnlr/CoFe二層膜の界面磁性研究では、Mnの非補償スピンが反強磁性と強磁性界面付近に選択的に誘起される事実を透過MCD実験により明らかにした(JAP101,09E510(2007)).さらに、強磁性層(FeCo)におけるFeとCoの組成比を変化させると、交換異方性エネルギー(J_k)とMCD強度に比例関係が成立することを見出した(論文準備中).また、希土類内包フラーレンの磁気特性解明のためのMCD実験は、名古屋大の篠原教授との共同研究として進められ、Er,Gd内包フラーレンの他、Gd内包フラーレンをカーボンナノチューブ内に取り入れた、いわゆる、Gdピーポットの磁気特性(常磁性帯磁率、ワイス温度)を明らかにした(Phys.Rev.B76,172409(2007)andJ.Phys.ChemC112,6103(2008)).以上の成果の他にも、Auの傾斜基板上に成長させたFeのナノワイヤーに関するMCD実験等でも成果(Phys.RevB75,245423(2007))を得ており、本研究課題によってMCDによるナノ材料を中心とした新規磁性体の磁気特性研究を加速的に推し進めることに成功した.

  12. 3d遷移金属および希土類合金の硬X線発光磁気円二色性の研究

    七尾 進, 渡辺 康裕, 中村 哲也

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

    研究種目:Grant-in-Aid for Scientific Research (B)

    研究機関:The University of Tokyo

    2001年 ~ 2003年

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    本研究は、X線によって物質中の電子が中間状態に励起された後の2次光学過程から放出されるX線のエネルギースペクトル(XES)においてスピン情報をもったXES、すなわちMCD-XESの測定法の開発と遷移金属および希土類金属への応用を目的としている。 最も大きな成果は、KEK-PFにおいてSm-Co合金試料の発光MCDの測定を行い精度のよい測定結果を得るとともに、この実験結果を理論計算グループの計算結果と比較検討したことである。この結果は論文としてまとめ学術雑誌上で公表された。その内容は、Sm_<21>Co_<79>アモルファス合金のL_3M_<4,5>とL_2M_4遷移に対するMCD-XESを精密に測定し、そのスペクトルを双極子遷移成分および四重極遷移成分に分離解析するとともに、これらのスペクトル対する精密な理論計算を行い各成分の内容を詳細に解析したものである。 また、SPring-8においては、XES用のビームラインを立ち上げのために、東北大多元研のメンバーと共に、SPring-8におけるXES測定のための測定装置の製作と整備および種々の基礎実験を行った。すなわち、集光ミラー、二次元検出器、二次元検出器用エネルギー解析装置およびゴニオメータの設置・整備を行った。また、XESのMCD実験を遂行するために、円偏光生成装置(移相子システム)を設計、製作し、動作テスト、試験的スペクトル測定を行った。 これにより、MCD-XESを含め広い範囲に応用可能な高分解能XAFSの測定・解析法を確立できた。これはLifetime-broadening-suppressed/free XANESと命名されており、XESのスペクトルから内殻電子の寿命に由来する分解能の劣化の影響を受けない高分解能のXANESスペクトルを導出するものである。この測定法は、特に将来光源の強度が数倍向上した場合、MCD-XESの応用をきわめて広範な領域に広げるものである。

  13. 元素選択的磁気ヒステリシスにより多元系性材料の研究

    中村 哲也

    2001年 ~ 2002年

    詳細を見る 詳細を閉じる

    本研究は、Nd-Fe-B系薄膜磁石をはじめとする希土類-遷移金属磁性体について、硬X線MCDを用いた元素選択磁気ヒステリシス(ESMH : Element Specific Magnetic Hysteresis)をSPring-8において測定し、元素選択磁化測定技術と解釈を発展させること、さらに、硬X線ESMHと通常の磁気ヒステリシス曲線とを比較して、(1)硬X線ESMHの特徴、問題点についての知見を得ること、(2)Non-collinear磁気構造(希土類と遷移金属の磁気モーメントが平行に揃わない磁気状態)における、希土類と遷移金属の磁気モーメントの挙動分離を具体的な目的とした。この計画で硬X線を用いることを優先した理由は、次の[1],[2]の理由による。[1]軟X線は試料を超高真空下に置くことが必要である点で実験が難しいが、硬X線ではその必要がなく簡便である、[2]試料への強磁場、高圧などの印加が容易であり、多彩な試料環境下で測定が可能である。SPring-8の共同利用研究採択課題「希土類元素L吸収端における四重極遷移XMCD理論の実験的検証」でESMの予備調査を行い、続いて課題「XMCDによる元素選択的磁気測定を用いた希土類合金のNon-Collinear磁気構造解析」において、DyCo_5合金におけるDy, CoのESM実験を遂行した。本結果は硬X線ESMの性質を細かく調べた結果であり、論文を準備中である。論文に先だって学会発表を行ったところ、Spring-8における注目すべき研究成果トピックスとして「SPring-8 Research Frontiers 2001/2002」に原稿執筆依頼を受けている。

  14. 量子磁性体の物理と化学に関する共同研究

    勝又 紘一, 山崎 展樹, 田中 良和, 萩原 政幸, 松田 雅昌, 中村 哲也

    提供機関:Japan Society for the Promotion of Science

    制度名:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A).

    研究種目:Grant-in-Aid for Scientific Research (A).

    研究機関:RIKEN, The Institute of Physical and Chemical Research

    1999年 ~ 2000年

    詳細を見る 詳細を閉じる

    我々が発見したスピン量子数1を持つ擬一次元反強磁性体の磁場中相転移現象に関し、Ni(C_5H_<14>N_2)_2N_3(PF_6)(NDMAPと略称)について試料振動型磁化測定装置による高磁場中での磁化測定を行い、低温、高磁場中での磁気秩序状態についての知見を得た。この物質について、広い周波数・磁場の範囲をカバーする電子スピン共鳴装置(ESR)を用いて磁気励起を測定し、低温・高磁場において反強磁性共鳴信号の観測に成功し、磁気秩序が確かに誘起されていることを示した。NDMAPについて、超低温度、高磁場中での中性子散乱実験を行い、磁場誘起磁気長距離秩序に伴うブラッグ散乱の観測に成功した。磁場をかける結晶軸方向により、磁気秩序が3次元的になったり、2次元的になるという興味深い現象が見られた。 理論家との共同研究により、スピン1を持つ擬一次元ハイゼンベルグ反強磁性体の磁場対温度相図の解析を行った。一イオン型異方性が存在する場合、磁場をかける方向によりスピン相関の磁場依存性が異なり、無秩序相と磁気長距離秩序相との境界線が異方的になることが分かった。これは、NDMAPにおいて以前に我々が実験的に観測した事実をよく説明する。 スピン梯子と一次元鎖が共存する物質La_6Ca_8Cu_<24>O_<41>単結晶を育成し中性子散乱法により磁気励起を調べた。梯子からの磁気励起信号の観測に成功し、初めて、ブリルアンゾーンの広い領域にわたってスピン梯子の磁気励起の分散関係を求めることが出来た。この結果について理論的研究を行い、梯子の脚と横木方向の相互作用だけでは分散関係を説明できず、4体の相互作用を導入すると現象が矛盾なく説明できることを示した。その他、多くの量子磁性体を合成し、その磁性を研究した。

︎全件表示 ︎最初の5件までを表示

メディア報道 2

  1. X線による磁気検出の例外的ケースを理論予測 ~30年間の常識を覆す基礎研究の成果~

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    東北大学プレスリリース https://www.tohoku.ac.jp/japanese/2020/07/press20200714-03-magnet.html

    2020年7月13日

    メディア報道種別: インターネットメディア