Details of the Researcher

PHOTO

Seigo Soma
Section
Advanced Institute for Materials Research
Job title
Associate Professor
Degree

  • 博士（理学）（東北大学）

  • 修士（理学）（東北大学）

Education 2

  • Tohoku University　Graduate School, Division of Natural Science　物理学専攻

    - 2005/03/31

  • Tohoku University　Faculty of Science　物理学科

    - 1999/03/31

Committee Memberships 3

  • 日本放射光学会　編集委員

    2022/10 - 2024/09

  • 日本放射光学会　行事委員

    2017/10 - 2019/09

  • 日本物理学会　領域4 運営委員

    2017/10 - 2018/09

Professional Memberships 2

  • 日本放射光学会

  • 日本物理学会

Research Interests 8

  • Rashba effect

  • topological insulator

  • spin-resolved arpes

  • superconductivity

  • Fermi surface

  • band structure

  • high-resolution

  • photoemisssion

Research Areas 1

  • Natural sciences / Magnetism, superconductivity, and strongly correlated systems /

Awards 6

  1. 平成25年度科学技術分野の文部科学大臣表彰若手科学者賞

    2013/04/16　文部科学省　スピン分解光電子分光装置の開発と機能材料の電子構造の研究

  2. 第6回日本物理学会若手奨励賞

    2012/03/27　日本物理学会

  3. 第47回原田研究奨励賞

    2007/07　本多記念会

  4. 第２２回井上研究奨励賞

    2006/02　井上科学振興財団

  5. 笹川助成研究交付金

    2004/06　日本科学技術振興財団

  6. 青葉理学振興会 振興会賞

    2004/02　青葉理学振興会

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Papers 51

  1. Ultrafast relaxation dynamics and nonequilibrium processes in graphite Peer-reviewed

    Hao-Hsiang Jia, Yuki Nakata, Seigo Souma, Katsuaki Sugawara, Yang-Hao Chan, Cheng-Maw Cheng, Ming-Chang Chen, Takafumi Sato, Chih-Wei Luo, Ashish Chainani, Ping-Hui Lin

    Physical Review B　111　(19)　2025/05/28

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevb.111.195430 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  2. Spin-valley coupling enhanced high-TC ferromagnetism in a non-van der Waals monolayer Cr2Se3 on graphene Peer-reviewed

    C.-W. Chuang, T. Kawakami, K. Sugawara, K. Nakayama, S. Souma, M. Kitamura, K. Amemiya, K. Horiba, H. Kumigashira, G. Kremer, Y. Fagot-Revurat, D. Malterre, C. Bigi, F. Bertran, F. H. Chang, H. J. Lin, C. T. Chen, T. Takahashi, A. Chainani, T. Sato

    Nature Communications　16　(1)　2025/04/18

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1038/s41467-025-58643-3 　

    eISSN： 2041-1723

  3. Experimental verification of terahertz surface plasmon resonance using the Dirac electron system Bi2SexTe(3-x) Peer-reviewed

    Hinano Sugimoto, Kana Nishimura, Mayuko Takahashi, Ryo Okano, Miho Kitamura, Katsuaki Sugawara, Seigo Souma, Takafumi Sato, Masaki Kobayashi, Hitoshi Tabata

    Optical Materials Express　15　(4)　788-788　2025/03/19

    Publisher: Optica Publishing Group

    DOI： 10.1364/ome.553139 　

    eISSN： 2159-3930

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    Although the surface plasmon resonance excited by a Dirac electron system has gained considerable attention in the terahertz region, studies have been limited to grating-coupling surface plasmon resonance (GC-SPR) in Bi2Se3. In this study, we experimentally demonstrated terahertz prism-coupled surface plasmon resonance (PC-SPR) and GC-SPR in topological insulator systems, viz. Bi2Se3 (GC-SPR), Bi2Se2Te (GC-SPR), and Bi2Se3 (PC-SPR). The physical properties measured using angle-resolved photoemission spectroscopy indicate that the presence of surface state near the Fermi level is insufficient for SPR excitation; linearity of the Dirac cone is essential for SPR excitation in the THz range.

  4. Evolution of band structure in the kagome superconductor Cs(V1-xCrx)3Sb5: Toward universal understanding of charge density wave and superconducting phase diagrams Peer-reviewed

    Shuto Suzuki, Takemi Kato, Yongkai Li, Kosuke Nakayama, Zhiwei Wang, Seigo Souma, Kenichi Ozawa, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, Takashi Takahashi, Yugui Yao, Takafumi Sato

    Physical Review B　110　(16)　2024/10/15

    DOI： 10.1103/PhysRevB.110.165104 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  5. Ferromagnetism triggered by band tripling in ruthenate Sr4Ru3 O10 Peer-reviewed

    N. Watanabe, S. Souma, K. Nakayama, K. Yamauchi, J. F. Ribeiro, Y. Wang, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, T. Oguchi, Z. Q. Mao, Y. P. Chen, T. Sato

    Physical Review B　110　(15)　2024/10/15

    DOI： 10.1103/PhysRevB.110.155134 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  6. Universal role of combined symmetry for the protection of the Dirac cone in antiferromagnetic topological insulators Peer-reviewed

    Asuka Honma, Noriyuki Kabeya, Seigo Souma, Yongjian Wang, Kunihiko Yamauchi, Kosuke Nakayama, Daichi Takane, Kenichi Ozawa, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, Tamio Oguchi, Takashi Takahashi, Noriaki Kimura, Yoichi Ando, Takafumi Sato

    Physical Review B　110　(11)　2024/09/26

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevb.110.115152 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  7. Observation of edge states derived from topological helix chains Peer-reviewed

    K. Nakayama, A. Tokuyama, K. Yamauchi, A. Moriya, T. Kato, K. Sugawara, S. Souma, M. Kitamura, K. Horiba, H. Kumigashira, T. Oguchi, T. Takahashi, K. Segawa, T. Sato

    Nature　631　(8019)　54-59　2024/06/05

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1038/s41586-024-07484-z 　

    ISSN： 0028-0836

    eISSN： 1476-4687

  8. 180 °-twisted bilayer <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>ReSe</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math> as an artificial noncentrosymmetric semiconductor Peer-reviewed

    S. Akatsuka, M. Sakano, T. Yamamoto, T. Nomoto, R. Arita, R. Murata, T. Sasagawa, K. Watanabe, T. Taniguchi, N. Mitsuishi, M. Kitamura, K. Horiba, K. Sugawara, S. Souma, T. Sato, H. Kumigashira, K. Shinokita, H. Wang, K. Matsuda, S. Masubuchi, T. Machida, K. Ishizaka

    Physical Review Research　6　(2)　2024/06/03

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevresearch.6.l022048 　

    eISSN： 2643-1564

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    We have fabricated a 180 °-twisted bilayer ReSe2 by stacking two centrosymmetric monolayer ReSe2 flakes in opposite directions, which is expected to cause the loss of spatial inversion symmetry. We successfully observed spatial inversion-symmetry breaking, in contrast to the monolayer and natural bilayer ReSe2 by the second harmonic generation. ARPES measurements further revealed emergent band dispersions in the 180 °-twisted bilayer ReSe2, distinct from those of the monolayer ReSe2 used in its fabrication. The band calculation shows the finite lifting of spin degeneracy (∼50 meV) distinct from natural monolayer and bilayer ReSe2, which demonstrates that the spin-momentum locked state leading to Berry curvature related phenomena can be realized even with the stacking of centrosymmetric monolayers. Published by the American Physical Society 2024

  9. Indication of exchange interaction induced spin splitting in unoccupied electronic states of the high-TC ferromagnet (Cr0.35Sb0.65)2Te3 Peer-reviewed

    C. W. Chuang, Y. Nakata, K. Hori, S. Gupta, F. M. F. de Groot, A. Fujimori, T. P. T. Nguyen, K. Yamauchi, I. Rajput, A. Lakhani, F.-H. Chang, H.-J. Lin, C.-T. Chen, F. Matsukura, S. Souma, T. Takahashi, T. Sato, A. Chainani

    Physical Review B　109　(19)　2024/05/10

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevb.109.195134 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  10. Observation of a giant band splitting in altermagnetic MnTe Peer-reviewed

    T. Osumi, S. Souma, T. Aoyama, K. Yamauchi, A. Honma, K. Nakayama, T. Takahashi, K. Ohgushi, T. Sato

    Physical Review B　109　(11)　2024/03/01

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevb.109.115102 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  11. Antiferromagnetic topological insulator with selectively gapped Dirac cones Peer-reviewed

    A. Honma, D. Takane, S. Souma, K. Yamauchi, Y. Wang, K. Nakayama, K. Sugawara, M. Kitamura, K. Horiba, H. Kumigashira, K. Tanaka, T. K. Kim, C. Cacho, T. Oguchi, T. Takahashi, Yoichi Ando, T. Sato

    Nature Communications　14　(1)　2023/11/17

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1038/s41467-023-42782-6 　

    eISSN： 2041-1723

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    Abstract Antiferromagnetic (AF) topological materials offer a fertile ground to explore a variety of quantum phenomena such as axion magnetoelectric dynamics and chiral Majorana fermions. To realize such intriguing states, it is essential to establish a direct link between electronic states and topology in the AF phase, whereas this has been challenging because of the lack of a suitable materials platform. Here we report the experimental realization of the AF topological-insulator phase in NdBi. By using micro-focused angle-resolved photoemission spectroscopy, we discovered contrasting surface electronic states for two types of AF domains; the surface having the out-of-plane component in the AF-ordering vector displays Dirac-cone states with a gigantic energy gap, whereas the surface parallel to the AF-ordering vector hosts gapless Dirac states despite the time-reversal-symmetry breaking. The present results establish an essential role of combined symmetry to protect massless Dirac fermions under the presence of AF order and widen opportunities to realize exotic phenomena utilizing AF topological materials.

  12. Moiré‐Assisted Realization of Octahedral MoTe2 Monolayer Peer-reviewed

    Yasuaki Saruta, Katsuaki Sugawara, Hirofumi Oka, Tappei Kawakami, Takemi Kato, Kosuke Nakayama, Seigo Souma, Takashi Takahashi, Tomoteru Fukumura, Takafumi Sato

    Advanced Science　2023/10/22

    Publisher: Wiley

    DOI： 10.1002/advs.202304461 　

    ISSN： 2198-3844

    eISSN： 2198-3844

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    Abstract A current key challenge in 2D materials is the realization of emergent quantum phenomena in hetero structures via controlling the moiré potential created by the periodicity mismatch between adjacent layers, as highlighted by the discovery of superconductivity in twisted bilayer graphene. Generally, the lattice structure of the original host material remains unchanged even after the moiré superlattice is formed. However, much less attention is paid for the possibility that the moiré potential can also modify the original crystal structure itself. Here, it is demonstrated that octahedral MoTe2 which is unstable in bulk is stabilized in a commensurate MoTe2/graphene hetero‐bilayer due to the moiré potential created between the two layers. It is found that the reconstruction of electronic states via the moiré potential is responsible for this stabilization, as evidenced by the energy‐gap opening at the Fermi level observed by angle‐resolved photoemission and scanning tunneling spectroscopies. The present results provide a fresh approach to realize novel 2D quantum phases by utilizing the moiré potential.

  13. Switching of charge-density wave by carrier tuning in monolayer TiTe2 Peer-reviewed

    Koki Yanagizawa, Katsuaki Sugawara, Tappei Kawakami, Ryuichi Ando, Ken Yaegashi, Kosuke Nakayama, Seigo Souma, Kiyohisa Tanaka, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, Takashi Takahashi, Takafumi Sato

    Physical Review Materials　7　(10)　2023/10/18

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevmaterials.7.104002 　

    eISSN： 2475-9953

  14. Unusual surface states associated with PT-symmetry breaking and antiferromagnetic band folding in NdSb Peer-reviewed

    Asuka Honma, Daichi Takane, Seigo Souma, Yongjian Wang, Kosuke Nakayama, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, Takashi Takahashi, Yoichi Ando, Takafumi Sato

    Physical Review B　108　(11)　2023/09/11

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevb.108.115118 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  15. Surface-termination-dependent electronic states in kagome superconductors AV3Sb5 (A=K, Rb, Cs) studied by micro-ARPES Peer-reviewed

    Takemi Kato, Yongkai Li, Min Liu, Kosuke Nakayama, Zhiwei Wang, Seigo Souma, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, Takashi Takahashi, Yugui Yao, Takafumi Sato

    Physical Review B　107　(24)　2023/06/29

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevb.107.245143 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  16. Visualizing crystal twin boundaries of bismuth by high-spatial-resolution ARPES Peer-reviewed

    Ayumi Moriya, Kosuke Nakayama, Tappei Kawakami, Kensaku Maeda, Atsuya Tokuyama, Seigo Souma, Chaoyu Chen, José Avila, Maria Carmen Asensio, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, Takashi Takahashi, Kozo Fujiwara, Kouji Segawa, Takafumi Sato

    Physical Review Research　5　(2)　2023/06/06

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevresearch.5.023152 　

    eISSN： 2643-1564

  17. Charge-density wave associated with higher-order Fermi-surface nesting in monolayer VS2 Peer-reviewed

    Tappei Kawakami, Katsuaki Sugawara, Hirofumi Oka, Kosuke Nakayama, Ken Yaegashi, Seigo Souma, Takashi Takahashi, Tomoteru Fukumura, Takafumi Sato

    npj 2D Materials and Applications　7　(1)　2023/05/02

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1038/s41699-023-00395-z 　

    eISSN： 2397-7132

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    Abstract Fermi-surface (FS) nesting originating from Peierls’ idea of electronic instabilities in one-dimensional materials is a key concept to stabilize charge-density wave (CDW), whereas its applicability to two-dimensional (2D) materials is under intensive debate. Here we report unusual CDW associated with the higher-order FS nesting in monolayer 2D VS2. Angle-resolved photoemission spectroscopy and scanning tunneling microscopy uncovered stripe CDW with $$\sqrt {21} R10.9^\circ \times \sqrt 3 R30^\circ$$ periodicity together with an energy-gap opening on the entire FS. We suggest that this CDW involves the higher-order FS-nesting vector 2q twice larger than that of the normal one (q), as supported by the anomalies in the calculated phonon dispersion and electronic susceptibility. The present results suggest that the cooperation of q and 2q nesting leads to the fully gapped CDW state unlike the case of conventional single q nesting which produces a partial gap, pointing to an intriguing mechanism of CDW transition.

  18. Direct Imaging of Band Structure for Powdered Rhombohedral Boron Monosulfide by Microfocused ARPES Peer-reviewed

    Katsuaki Sugawara, Haruki Kusaka, Tappei Kawakami, Koki Yanagizawa, Asuka Honma, Seigo Souma, Kosuke Nakayama, Masashi Miyakawa, Takashi Taniguchi, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, Takashi Takahashi, Shin-ichi Orimo, Masayuki Toyoda, Susumu Saito, Takahiro Kondo, Takafumi Sato

    Nano Letters　23　(5)　1673-1679　2023/02/27

    Publisher: American Chemical Society (ACS)

    DOI： 10.1021/acs.nanolett.2c04048 　

    ISSN： 1530-6984

    eISSN： 1530-6992

  19. Charge order with unusual star-of-David lattice in monolayer NbTe2 Peer-reviewed

    Taiki Taguchi, Katsuaki Sugawara, Hirofumi Oka, Tappei Kawakami, Yasuaki Saruta, Takemi Kato, Kosuke Nakayama, Seigo Souma, Takashi Takahashi, Tomoteru Fukumura, Takafumi Sato

    Physical Review B　107　(4)　2023/01/17

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevb.107.l041105 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  20. Fermiology and Origin of Tc Enhancement in a Kagome Superconductor Cs (V1-xNbx)3Sb5 Peer-reviewed

    Takemi Kato, Yongkai Li, Kosuke Nakayama, Zhiwei Wang, Seigo Souma, Fumihiko Matsui, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, Takashi Takahashi, Yugui Yao, Takafumi Sato

    Physical Review Letters　129　(20)　2022/11/11

    DOI： 10.1103/PhysRevLett.129.206402 　

    ISSN： 0031-9007

    eISSN： 1079-7114

  21. Fermiology of a topological line-nodal compound CaSb2 and its implication to superconductivity: Angle-resolved photoemission study Peer-reviewed

    Chien Wen Chuang, Seigo Souma, Ayumi Moriya, Kosuke Nakayama, Atsutoshi Ikeda, Mayo Kawaguchi, Keito Obata, Shanta Ranjan Saha, Hidemitsu Takahashi, Shunsaku Kitagawa, Kenji Ishida, Kiyohisa Tanaka, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, Takashi Takahashi, Shingo Yonezawa, Johnpierre Paglione, Yoshiteru Maeno, Takafumi Sato

    Physical Review Materials　6　(10)　2022/10

    DOI： 10.1103/PhysRevMaterials.6.104203 　

    eISSN： 2475-9953

  22. Polarity-dependent charge density wave in the kagome superconductor CsV3Sb5 Peer-reviewed

    Takemi Kato, Yongkai Li, Kosuke Nakayama, Zhiwei Wang, Seigo Souma, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, Takashi Takahashi, Takafumi Sato

    Physical Review B　106　(12)　2022/09/15

    DOI： 10.1103/PhysRevB.106.L121112 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  23. Rhombic Fermi surfaces in a ferromagnetic MnGa thin film with perpendicular magnetic anisotropy Peer-reviewed

    M. Kobayashi, N. H. D. Khang, T. Takeda, K. Araki, R. Okano, M. Suzuki, K. Kuroda, K. Yaji, K. Sugawara, S. Souma, K. Nakayama, K. Yamauchi, M. Kitamura, K. Horiba, A. Fujimori, T. Sato, S. Shin, M. Tanaka, P. N. Hai

    Physical Review Materials　2022/07

    DOI： 10.1103/physrevmaterials.6.074403 　

    ISSN： 2475-9953

  24. Pb/Bi heterostructure as a versatile platform to realize topological superconductivity Peer-reviewed

    Ikuko Watanabe, Seigo Souma, Kosuke Nakayama, Katsuaki Sugawara, Chi Xuan Trang, Kouji Segawa, Kunihiko Yamauchi, Tamio Oguchi, Takashi Takahashi, Takafumi Sato

    Progress of Theoretical and Experimental Physics　2022　(4)　2022/04/07

    Publisher: Oxford University Press (OUP)

    DOI： 10.1093/ptep/ptab105 　

    eISSN： 2050-3911

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    Abstract Realization of topological superconductors (TSCs) hosting Majorana fermions is an exciting challenge in materials science. Majorana fermions are predicted to emerge at vortex cores of two-dimensional (2D) TSCs and at both ends of one-dimensional (1D) TSCs; these two types of TSCs have been explored independently in different materials. Here, a system which has a potential to access both 1D and 2D TSCs in a single platform, Pb(111)/Bi(111) heterostructure, is proposed. One to twenty bilayers (BLs) of Bi(111) ultra-thin films are epitaxially fabricated on TlBiSe$_2$, and an intriguing evolution of electronic states upon variation of Bi-layer thickness is revealed by angle-resolved photoemission spectroscopy. The metallic quantum-well states at 1–2BLs are found to turn into the Rashba states at 5–20BLs, via the semiconducting states at 3BL. Fabrication of a Pb(111) film on 20BL Bi(111) enables observation of the proximity-induced superconductivity in Bi(111) as evident from a 1 meV energy gap at 5 K; these energy and temperature scales are considerably larger than those of Rashba superconductors. The Pb/Bi heterostructure serves as a versatile platform to study the interplay among proximity-induced superconductivity, band structure, and topology.

  25. Development of a versatile micro-focused angle-resolved photoemission spectroscopy system with Kirkpatrick-Baez mirror optics Peer-reviewed

    Miho Kitamura, Seigo Souma, Asuka Honma, Daisuke Wakabayashi, Hirokazu Tanaka, Akio Toyoshima, Kenta Amemiya, Tappei Kawakami, Katsuaki Sugawara, Kosuke Nakayama, Kohei Yoshimatsu, Hiroshi Kumigashira, Takafumi Sato, Koji Horiba

    Review of Scientific Instruments　93　(3)　2022/03/01

    DOI： 10.1063/5.0074393 　

    ISSN： 0034-6748

    eISSN： 1089-7623

  26. Dirac semimetal phase and switching of band inversion in XMg2Bi2 (X = Ba and Sr) Peer-reviewed

    Daichi Takane, Yuya Kubota, Kosuke Nakayama, Tappei Kawakami, Kunihiko Yamauchi, Seigo Souma, Takemi Kato, Katsuaki Sugawara, Shin ichiro Ideta, Kiyohisa Tanaka, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, Tamio Oguchi, Takashi Takahashi, Kouji Segawa, Takafumi Sato

    Scientific Reports　11　(1)　2021/12

    DOI： 10.1038/s41598-021-01333-z 　

    eISSN： 2045-2322

  27. Large magnetoresistance of a compensated metal Cu2Sb correlated with its Fermi surface topology Peer-reviewed

    Mizuki Endo, Hideyuki Kawasoko, Seigo Soma, Kunihiko Yamauchi, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, Noriaki Kimura, Tamio Oguchi, Takafumi Sato, Tomoteru Fukumura

    Physical Review Materials　5　(10)　2021/10/06

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevmaterials.5.105002 　

    eISSN： 2475-9953

  28. Electronic states of multilayer VTe2: Quasi-one-dimensional Fermi surface and implications for charge density waves Peer-reviewed

    Tappei Kawakami, Katsuaki Sugawara, Takemi Kato, Taiki Taguchi, Seigo Souma, Takashi Takahashi, Takafumi Sato

    PHYSICAL REVIEW B　104　(4)　2021/07

    DOI： 10.1103/PhysRevB.104.045136 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  29. Unveiling quasiparticle dynamics of topological insulators through Bayesian modelling Peer-reviewed

    Satoru Tokuda, Seigo Souma, Kouji Segawa, Takashi Takahashi, Yoichi Ando, Takeshi Nakanishi, Takafumi Sato

    COMMUNICATIONS PHYSICS　4　(1)　2021/07

    DOI： 10.1038/s42005-021-00673-6 　

    ISSN： 2399-3650

    eISSN： 2399-3650

  30. Manipulation of Dirac Cone in Topological Insulator/Topological Insulator Heterostructure Peer-reviewed

    Takumi Sato, Katsuaki Sugawara, Takemi Kato, Yuki Nakata, Seigo Souma, Kunihiko Yamauchi, Tamio Oguchi, Takashi Takahashi, Takafumi Sato

    ACS Applied Electronic Materials　3　(3)　1080-1085　2021/03/23

    Publisher: American Chemical Society (ACS)

    DOI： 10.1021/acsaelm.0c00918 　

    ISSN： 2637-6113

    eISSN： 2637-6113

  31. Conversion of a conventional superconductor into a topological superconductor by topological proximity effect Peer-reviewed

    C. X. Trang, N. Shimamura, K. Nakayama, S. Souma, K. Sugawara, I. Watanabe, K. Yamauchi, T. Oguchi, K. Segawa, T. Takahashi, Yoichi Ando, T. Sato

    Nature Communications　11　(1)　2020/12

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1038/s41467-019-13946-0 　

    eISSN： 2041-1723

  32. Signature of band inversion in the antiferromagnetic phase of axion insulator candidate EuIn2As2 Peer-reviewed

    Takafumi Sato, Zhiwei Wang, Daichi Takane, Seigo Souma, Chaoxi Cui, Yongkai Li, Kosuke Nakayama, Tappei Kawakami, Yuya Kubota, Cephise Cacho, Timur K. Kim, Arian Arab, Vladimir N. Strocov, Yugui Yao, Takashi Takahashi

    PHYSICAL REVIEW RESEARCH　2　(3)　2020/09

    DOI： 10.1103/PhysRevResearch.2.033342 　

    eISSN： 2643-1564

  33. Unusual temperature evolution of the band structure of Bi(111) studied by angle-resolved photoemission spectroscopy and density functional theory Peer-reviewed

    Takafumi Sato, Keiko Yamada, Takao Kosaka, Seigo Souma, Kunihiko Yamauchi, Katsuaki Sugawara, Tamio Oguchi, Takashi Takahashi

    Physical Review B　102　(8)　2020/08/06

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevb.102.085112 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  34. Observation of inverted band structure in the topological Dirac semimetal candidate CaAuAs Peer-reviewed

    Kosuke Nakayama, Zhiwei Wang, Daichi Takane, Seigo Souma, Yuya Kubota, Yuki Nakata, Cephise Cacho, Timur Kim, Sandy Adhitia Ekahana, Ming Shi, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, Takashi Takahashi, Yoichi Ando, Takafumi Sato

    Physical Review B　102　(4)　2020/07/06

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevb.102.041104 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  35. Two-dimensional growth of conductive ultra-thin Sn films on insulating substrate with an Fe buffer layer International-journal Peer-reviewed

    Dingheng Zheng, Junichi Shiogai, Hisashi Inoue, Seigo Souma, Takafumi Sato, Atsushi Tsukazaki

    APL Materials　8　(6)　061103-1-061103-7　2020/06/04

    DOI： 10.1063/5.0009012 　

    ISSN： 2166-532X

  36. Magnetic-field-induced topological phase transition in Fe-doped (Bi,Sb)2Se3 heterostructures Peer-reviewed

    Y. Satake, J. Shiogai, G. P. Mazur, S. Kimura, S. Awaji, K. Fujiwara, T. Nojima, K. Nomura, S. Souma, T. Sato, T. Dietl, A. Tsukazaki

    Physical Review Materials　4　(4)　2020/04/21

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevmaterials.4.044202 　

    eISSN： 2475-9953

  37. Unusual change in the Dirac-cone energy band upon a two-step magnetic transition in CeBi Peer-reviewed

    Oinuma Hikaru, Souma Seigo, Nakayama Kosuke, Horiba Koji, Kumigashira Hiroshi, Yoshida Makoto, Ochiai Akira, Takahashi Takashi, Sato Takafumi

    PHYSICAL REVIEW B　100　(12)　2019/09/10

    DOI： 10.1103/PhysRevB.100.125122 　

    ISSN： 2469-9950

  38. Dimensionality reduction and band quantization induced by potassium intercalation in 1T-HfTe2 Peer-reviewed

    Y. Nakata, K. Sugawara, A. Chainani, K. Yamauchi, K. Nakayama, S. Souma, P.-Y. Chuang, C.-M. Cheng, T. Oguchi, K. Ueno, T. Takahashi, T. Sato

    PHYSICAL REVIEW MATERIALS　3　071001(R)　2019/07

  39. Monolayer VTe2: Incommensurate Fermi surface nesting and suppression of charge density waves Peer-reviewed

    Sugawara Katsuaki, Nakata Yuki, Fujii Kazuki, Nakayama Kosuke, Souma Seigo, Takahashi Takashi, Sato Takafumi

    PHYSICAL REVIEW B　99　(24)　2019/06/18

    DOI： 10.1103/PhysRevB.99.241404 　

    ISSN： 2469-9950

  40. Evidence for bulk nodal loops and universality of Dirac-node arc surface states in ZrGeXc (X-c = S, Se, Te) Peer-reviewed

    Nakamura Takechika, Souma Seigo, Wang Zhiwei, Yamauchi Kunihiko, Takane Daichi, Oinuma Hikaru, Nakayama Kosuke, Horiba Koji, Kumigashira Hiroshi, Oguchi Tamio, Takahashi Takashi, Ando Yoichi, Sato Takafumi

    PHYSICAL REVIEW B　99　(24)　2019/06/04

    DOI： 10.1103/PhysRevB.99.245105 　

    ISSN： 2469-9950

  41. Nanomosaic of Topological Dirac States on the Surface of Pb5Bi24Se41 Observed by Nano-ARPES Peer-reviewed

    Nakayama Kosuke, Souma Seigo, Trang Chi Xuan, Takane Daichi, Chen Chaoyu, Avila Jose, Takahashi Takashi, Sasaki Satoshi, Segawa Kouji, Carmen Asensio Maria, Ando Yoichi, Sato Takafumi

    NANO LETTERS　19　(6)　3737-3742　2019/06

    DOI： 10.1021/acs.nanolett.9b00875 　

    ISSN： 1530-6984

  42. Observation of Chiral Fermions with a Large Topological Charge and Associated Fermi-Arc Surface States in CoSi Peer-reviewed

    Takane Daichi, Wang Zhiwei, Souma Seigo, Nakayama Kosuke, Nakamura Takechika, Oinuma Hikaru, Nakata Yuki, Iwasawa Hideaki, Cacho Cephise, Kim Timur, Horiba Koji, Kumigashira Hiroshi, Takahashi Takashi, Ando Yoichi, Sato Takafumi

    PHYSICAL REVIEW LETTERS　122　(7)　2019/02/20

    DOI： 10.1103/PhysRevLett.122.076402 　

    ISSN： 0031-9007

  43. Ultrathin Bismuth Film on High-Temperature Cuprate Superconductor Bi2Sr2CaCu2O8+delta as a Candidate of a Topological Superconductor Peer-reviewed

    Shimamura, Natsumi, Sugawara, Katsuaki, Sucharitakul, Sukrit, Souma, Seigo, Iwaya, Katsuya, Nakayama, Kosuke, Trang, Chi Xuan, Yamauchi, Kunihiko, Oguchi, Tamio, Kudo, Kazutaka, Noji, Takashi, Koike, Yoji, Takahashi, Takashi, Hanaguri, Tetsuo, Sato, Takafumi

    ACS NANO　12　(11)　10977-10983　2018/11

    DOI： 10.1021/acsnano.8b04869 　

    ISSN： 1936-0851

    eISSN： 1936-086X

  44. Bulk superconducting gap of V3Si studied by low-energy ultra-high resolution photoemission spectroscopy Peer-reviewed

    T. Sato, S. Souma, K. Nakawyama, K. Sugawara, N. Toyota, T. Takahashi

    J. Electron Spectroscopy and Related Phenomena　208　40-42　2016/01/04

    DOI： 10.1016/j.elspec.2015.04.009 　

  45. Switching of Dirac-Fermion Mass at the Interface of Ultrathin Ferromagnet and Rashba Metal Peer-reviewed

    K. Honma, T. Sato, S. Souma, K. Sugawara, Y. Tanaka, T. Takahashi

    Phys. REv. Lett.　115　266401　2015/04/06

    DOI： 10.1103/PhysRevLett.115.266401 　

  46. Anomalous Rashba effect of bismuth(111) thin films studied by high-resolution spin- and angle-resolved photoemission spectroscopy Peer-reviewed

    Akari Takayama, Takafumi Sato, Seigo Souma, Takashi Takahashi

    Journal of Vacuum Science and Technology B:Nanotechnology and Microelectronics　30　(4)　2012

    Publisher: AVS Science and Technology Society

    DOI： 10.1116/1.4731467 　

    ISSN： 2166-2754 2166-2746

  47. Ultrahigh-resolution spin-resolved photoemission spectrometer with a mini Mott detector (vol 81, 095101, 2010) Peer-reviewed

    Souma, S. Takayama, A. Sugawara, K. Sato, T. Takahashi, T

    REVIEW OF SCIENTIFIC INSTRUMENTS　81　(10)　109901　2010/10

    DOI： 10.1063/1.3503485 　

  48. Fermi Arc in The Superconducting State of Impurity-Doped High-Temperature Superconductors Peer-reviewed

    T., Sato, K., Terashima, K., Nakayama, S., Souma, T., Takahashi, T., Yamamoto, K., Kadowaki

    Phys. Rev. B　78　(10)　100502(1-4)　2008/09

    Publisher: APS

    DOI： 10.1103/PhysRevB.78.100502 　

  49. Angle-resolved photoemission spectroscopy on metallic sodium tungsten bronzes NaxWO3 Peer-reviewed

    S. Raj, D. Hashimoto, H. Matsui, S. Souma, T. Sato, T. Takahashi, S. Ray, A. Chakraborty, D. D. Sarma, P. Mahadevan, W. H. McCarroll, M. Greenblatt

    Phys. Rev. B　72　125125-1-8　2005/12/01

    DOI： 10.1103/PhysRevB.72.125125 　

  50. High-resolution angle-resolved photoemission study of incommensurate charge-density-wave compound CeTe3 Peer-reviewed

    H. Komoda, T. Sato, S. Souma, T. Takahashi, Y. Ito, K. Suzuki

    Physical Review B - Condensed Matter and Materials Physics　70　(19)　1-6　2004/11

    DOI： 10.1103/PhysRevB.70.195101 　

    ISSN： 0163-1829

  51. Band structure of UPd3 studied by ultrahigh-resolution angle-resolved photoemission spectroscopy Peer-reviewed

    T. Ito, H. Kumigashira, S. Souma, T. Takahashi, Y. Haga, Y. Tokiwa, Y. Onuki

    Physical Review B - Condensed Matter and Materials Physics　66　(24)　2451101-2451106　2002/12/15

    ISSN： 0163-1829

Show all ︎Show first 5

Misc. 185

  1. Novel surface states of a kagome superconductor LaRh3B2 studied by ARPES

    加藤剛臣, 中山耕輔, 大隅拓海, 相馬清吾, 相馬清吾, 本間飛鳥, ANTEZAK Alexandre, 田中清尚, 田中清尚, 北村未歩, 小澤健一, 堀場弘司, 組頭広志, 高橋隆, FORTUNA Franck, SANTANDER-SYRO Andres Felipe, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　79　(2)　2024

    ISSN： 2189-079X

  2. Electronic structure of Cr-substituted kagome superconductor Cs(V1-xCrx)3Sb5 observed by micro-ARPES

    鈴木崇人, 加藤剛臣, 中山耕輔, LI Yongkai, WANG Zhiwei, 相馬清吾, 相馬清吾, 小澤健一, 北村未歩, 北村未歩, 堀場弘司, 組頭広志, 高橋隆, YAO Yugui, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　79　(1)　2024

    ISSN： 2189-079X

  3. Imaging the electronic structure of Te(0001) using micro-ARPES

    中山耕輔, 徳山敦也, 山内邦彦, 守谷歩美, 加藤剛臣, 菅原克明, 菅原克明, 菅原克明, 相馬清吾, 相馬清吾, 北村未歩, 北村未歩, 堀場弘司, 組頭広志, 小口多美夫, 高橋隆, 瀬川耕司, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　79　(1)　2024

    ISSN： 2189-079X

  4. Electronic structure of Laves phase compound CsBi2 studied by high-resolution ARPES

    森田雄晴, 加藤剛臣, 中山耕輔, LI Yongkai, WANG Zhiwei, 相馬清吾, 相馬清吾, 田中清尚, 田中清尚, 小澤健一, 北村未歩, 堀場弘司, 組頭広志, 高橋隆, YAO Yugui, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　79　(1)　2024

    ISSN： 2189-079X

  5. High-resolution ARPES study of Weyl semimetal PtBi2

    森田雄晴, 中山耕輔, 加藤剛臣, 相馬清吾, 相馬清吾, 眞崎世聞, 生島匠, 守安悠人, 萩原健太, 松井文彦, 松井文彦, 田中清尚, 田中清尚, 小澤健一, 志賀大亮, 組頭広志, 高橋隆, 工藤一貴, 工藤一貴, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　79　(2)　2024

    ISSN： 2189-079X

  6. Observation of edge states derived from topological helix chains: micro-ARPES

    中山耕輔, 徳山敦也, 山内邦彦, 守谷歩美, 加藤剛臣, 菅原克明, 菅原克明, 菅原克明, 相馬清吾, 相馬清吾, 北村未歩, 北村未歩, 堀場弘司, 組頭広志, 小口多美夫, 高橋隆, 瀬川耕司, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　79　(2)　2024

    ISSN： 2189-079X

  7. ARPES study of a topological insulator candidate CdGeAs2

    岩谷拓実, 守谷歩美, 中山耕輔, 中山耕輔, 本間飛鳥, 加藤剛臣, 川上竜平, 菅原克明, 菅原克明, 菅原克明, 相馬清吾, 相馬清吾, 田中清尚, 北村未歩, 堀場弘司, 堀場弘司, 組頭広志, 高橋隆, 瀬川耕司, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　78　(1)　2023

    ISSN： 2189-079X

  8. Electronic states of kagome superconductors AV3Sb5 (A=K, Rb, Cs) studied by micro-ARPES

    加藤剛臣, 中山耕輔, 中山耕輔, LI Yongkai, LIU Min, WANG Zhiwei, 相馬清吾, 相馬清吾, 北村未歩, 堀場弘司, 組頭広志, 高橋隆, YAO Yugui, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　78　(1)　2023

    ISSN： 2189-079X

  9. High-resolution ARPES study of carrier-controlled chalcopyrite CdGeAs2

    岩谷拓実, 守谷歩美, 中山耕輔, 本間飛鳥, 加藤剛臣, 川上竜平, 菅原克明, 菅原克明, 菅原克明, 相馬清吾, 相馬清吾, 田中清尚, 北村未歩, 北村未歩, 堀場弘司, 組頭広志, 高橋隆, 瀬川耕司, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　78　(2)　2023

    ISSN： 2189-079X

  10. Micro-ARPES study of kagome-lattice material LaRh3B2

    大隅拓海, 加藤剛臣, 本間飛鳥, 中山耕輔, 相馬清吾, 相馬清吾, 田中清尚, 北村未歩, 北村未歩, 堀場弘司, 組頭広志, 高橋隆, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　78　(2)　2023

    ISSN： 2189-079X

  11. Micro-ARPES study of Cr-substituted kagome superconductor CsV3Sb5

    鈴木崇人, 加藤剛臣, 中山耕輔, LI Yongkai, WANG Zhiwei, 相馬清吾, 相馬清吾, 北村未歩, 北村未歩, 堀場弘司, 組頭広志, 高橋隆, YAO Yugui, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　78　(2)　2023

    ISSN： 2189-079X

  12. カゴメ超伝導体CsV3Sb5のCDW転移:μ-ARPES

    加藤剛臣, 中山耕輔, 中山耕輔, LI Yongkai, 相馬清吾, 相馬清吾, LIU Min, WANG Zhiwei, 北村未歩, 堀場弘司, 組頭広志, 高橋隆, 高橋隆, YAO Yugui, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本放射光学会年会・放射光科学合同シンポジウム(Web)　35th　2022

  13. 原子層VS2の電子状態:マイクロARPES

    川上竜平, 加藤剛臣, 猿田康朗, 中山耕輔, 中山耕輔, 菅原克明, 菅原克明, 菅原克明, 菅原克明, 相馬清吾, 相馬清吾, 北村未歩, 堀場弘司, 組頭広志, 高橋隆, 高橋隆, 高橋隆, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本放射光学会年会・放射光科学合同シンポジウム(Web)　35th　2022

  14. Anomalous electronic states of atomic-layer MoTe2 thin film studied by micro ARPES

    菅原克明, 菅原克明, 菅原克明, 菅原克明, 猿田康朗, 岡博文, 川上竜平, 加藤剛臣, 中山耕輔, 中山耕輔, 相馬清吾, 相馬清吾, 北村未歩, 堀場弘司, 組頭広志, 高橋隆, 高橋隆, 高橋隆, 福村知昭, 福村知昭, 福村知昭, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　77　(1)　2022

    ISSN： 2189-079X

  15. Charge-density-wave phase of atomic-layer VS2 thin films studied by μ-ARPES

    川上竜平, 岡博文, 加藤剛臣, 猿田康朗, 中山耕輔, 中山耕輔, 菅原克明, 菅原克明, 菅原克明, 菅原克明, 相馬清吾, 相馬清吾, 北村未歩, 堀場弘司, 組頭広志, 高橋隆, 高橋隆, 高橋隆, 福村知昭, 福村知昭, 福村知昭, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　77　(1)　2022

    ISSN： 2189-079X

  16. ARPES study of a topological insulator candidate with chalcopyrite structure

    岩谷拓実, 守谷歩美, 中山耕輔, 中山耕輔, 加藤剛臣, 相馬清吾, 相馬清吾, 北村未歩, 堀場弘司, 堀場弘司, 組頭広志, 高橋隆, 瀬川耕司, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　77　(2)　2022

    ISSN： 2189-079X

  17. Domain-selective micro-ARPES study of a kagome superconductor CsV3Sb5

    加藤剛臣, 中山耕輔, 中山耕輔, LI Yongkai, WANG Zhiwei, 相馬清吾, 相馬清吾, 北村未歩, 堀場弘司, 組頭広志, 高橋隆, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　77　(2)　2022

    ISSN： 2189-079X

  18. Nb substitution effect on a kagome superconductor CsV3Sb5 studied by high-resolution ARPES

    加藤剛臣, 中山耕輔, 中山耕輔, LI Yongkai, WANG Zhiwei, 相馬清吾, 相馬清吾, 松井文彦, 北村未歩, 堀場弘司, 組頭広志, 高橋隆, YAO Yugui, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　77　(2)　2022

    ISSN： 2189-079X

  19. Electronic states of atomic-layer MoTe2 thin film studied by Micro-ARPES

    菅原克明, 菅原克明, 菅原克明, 猿田康朗, 岡博文, 川上竜平, 加藤剛臣, 中山耕輔, 中山耕輔, 相馬清吾, 相馬清吾, 北村未歩, 堀場弘司, 組頭広志, 高橋隆, 福村知昭, 福村知昭, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    応用物理学会秋季学術講演会講演予稿集(CD-ROM)　83rd　2022

    ISSN： 2758-4704

  20. Micro-ARPES study of the electronic structure in novel Dirac semimetals

    中山耕輔, 中山耕輔, 久保田雄也, 高根大地, 相馬清吾, 相馬清吾, 本間飛鳥, 川上竜平, 加藤剛臣, 菅原克明, 菅原克明, 菅原克明, 菅原克明, 高橋隆, 高橋隆, 高橋隆, 瀬川耕司, 出田真一郎, 出田真一郎, 田中清尚, 田中清尚, 北村未歩, 堀場弘司, 堀場弘司, 組頭広志, 組頭広志, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　76　(1)　2021

    ISSN： 2189-079X

  21. Transition-metal dichalcogenide films studied by micro-ARPES

    菅原克明, 菅原克明, 菅原克明, 菅原克明, 川上竜平, 加藤剛臣, 田口大樹, 猿田康朗, 久保田雄也, 坪野竜治, 北村未歩, 堀場弘司, 組頭広志, 組頭広志, 上野啓司, 中山耕輔, 中山耕輔, 中山耕輔, 中山耕輔, 相馬清吾, 相馬清吾, 高橋隆, 高橋隆, 高橋隆, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　76　(1)　2021

    ISSN： 2189-079X

  22. High-resolution ARPES study of Dirac semimetal candidate BaMg2Bi2

    高根大地, 久保田雄也, 川上竜平, 加藤剛臣, 坪野竜治, 菅原克明, 菅原克明, 中山耕輔, 中山耕輔, 相馬清吾, 相馬清吾, 出田真一郎, 田中清尚, 田中清尚, 北村未歩, 堀場弘司, 堀場弘司, 組頭広志, 組頭広志, 高橋隆, 高橋隆, 高橋隆, 瀬川耕司, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　76　(1)　2021

    ISSN： 2189-079X

  23. Anomalous electronic states in atomic-layer NbTe2 studied by high-resolution ARPES

    菅原克明, 菅原克明, 菅原克明, 菅原克明, 田口大樹, 岡博文, 川上竜平, 猿田康朗, 加藤剛臣, 中山耕輔, 中山耕輔, 相馬清吾, 相馬清吾, 高橋隆, 高橋隆, 高橋隆, 福村知昭, 福村知昭, 福村知昭, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　76　(2)　2021

    ISSN： 2189-079X

  24. Micro-ARPES study of a new kagome superconductor CsV3Sb5

    加藤剛臣, 中山耕輔, 中山耕輔, LI Yongkai, 相馬清吾, 相馬清吾, LIU Min, WANG Zhiwei, 北村未歩, 堀場弘司, 組頭広志, 高橋隆, 高橋隆, YAO Yugui, 佐藤宇史, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　76　(2)　2021

    ISSN： 2189-079X

  25. ファンデルワールス強磁性体Cr2Ge2Te6の高分解能ARPES

    加藤剛臣, 伊東直洋, 川上竜平, 菅原克明, 菅原克明, 菅原克明, 相馬清吾, 相馬清吾, 中山耕輔, 高橋隆, 高橋隆, 高橋隆, 塩見雄毅, 齊藤英治, 齊藤英治, 齊藤英治, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本放射光学会年会・放射光科学合同シンポジウム(Web)　34th　2021

  26. Dirac gap in Bi2Se3/Cr2Ge2Te6 studied by high-resolution ARPES

    加藤剛臣, 伊東直洋, 川上竜平, 菅原克明, 菅原克明, 菅原克明, 菅原克明, 相馬清吾, 相馬清吾, 中山耕輔, 中山耕輔, 北村未歩, 堀場弘司, 堀場弘司, 組頭広志, 組頭広志, 高橋隆, 高橋隆, 高橋隆, 塩見雄毅, 齊藤英治, 齊藤英治, 齊藤英治, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　76　(1)　2021

    ISSN： 2189-079X

  27. NbTe2単原子層薄膜の高分解能ARPES

    田口大樹, 中田優樹, 川上竜平, 加藤剛臣, 佐藤匠, 菅原克明, 菅原克明, 菅原克明, 中山耕輔, 相馬清吾, 相馬清吾, 高橋隆, 高橋隆, 高橋隆, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本放射光学会年会・放射光科学合同シンポジウム(Web)　33rd　2020

  28. Ferromagnetic transition of van der Waals ferromagnet Cr2Ge2Te6 studied by high-resolution ARPES

    加藤剛臣, 伊東直洋, 川上竜平, 菅原克明, 菅原克明, 菅原克明, 相馬清吾, 相馬清吾, 中山耕輔, 高橋隆, 高橋隆, 高橋隆, 塩見雄毅, 齊藤英治, 齊藤英治, 齊藤英治, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　75　(1)　2020

    ISSN： 2189-079X

  29. Dirac electronic states of topological insulator/ferromagnet heterostructures studied by high-resolution ARPES

    加藤剛臣, 伊東直洋, 川上竜平, 久保田雄也, 田口大樹, 坪野竜治, 菅原克明, 菅原克明, 菅原克明, 相馬清吾, 相馬清吾, 中山耕輔, 高橋隆, 高橋隆, 高橋隆, 塩見雄毅, 齊藤英治, 齊藤英治, 齊藤英治, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　75　(2)　2020

    ISSN： 2189-079X

  30. トポロジカル絶縁体積層構造Fex(Bi1-ySby)2-xSe3/Bi2Se3の磁場誘起量子異常ホール効果

    佐竹遥介, 塩貝純一, 木村尚次郎, 淡路智, 藤原宏平, 野島勉, 相馬清吾, 佐藤宇史, 塚崎敦

    日本物理学会講演概要集(CD-ROM)　74　(1)　2019

    ISSN： 2189-079X

  31. トポロジカル絶縁体/ファンデルワールス強磁性体ハイブリッドの高分解能ARPES

    加藤剛臣, 伊東直洋, 佐藤匠, 中田優樹, 菅原克明, 菅原克明, 菅原克明, 相馬清吾, 相馬清吾, 中山耕輔, 高橋隆, 高橋隆, 高橋隆, 塩見雄毅, 齊藤英治, 齊藤英治, 齊藤英治, 佐藤宇史, 佐藤宇史, 佐藤宇史

    日本物理学会講演概要集(CD-ROM)　74　(2)　2019

    ISSN： 2189-079X

  32. Weyl fermion in matter

    相馬清吾

    Parity　32　(1)　2017/01

    Publisher: 丸善出版

  33. 10pAS-1 Topological proximity effect in Bi/TlBiSe_2 studied by high-resolution ARPES

    Shoman T., Takayama A., Sato T., Souma S., Takahashi T., Oguchi T., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　69　(2)　677-677　2014/08/22

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  34. 7aAX-9 Electronic states of superconducting Tl_5Te_3 studied by high-resolution ARPES

    Tanaka Y., Shoman T., Nakayama K., Souma S., Takahashi T., Toba T., Sasaki S., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　69　(2)　466-466　2014/08/22

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  35. 9pAJ-8 High-resolution ARPES study of a topological-superconductor candidate Cu_x(PbSe)_5(Bi_2Se_3)_<3m>

    Kimizuka H., Shouman T., Tanaka Y., Nakayama K., Souma S., Sato T., Takahashi T., Eto K., Sasaki S., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　69　(2)　531-531　2014/08/22

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  36. 9pAJ-5 High-resolution ARPES study of Co/W(110)

    Goto T., Honma K., Sugawara K., Souma S., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　69　(2)　530-530　2014/08/22

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  37. 10pAS-1 Topological proximity effect in Bi/TlBiSe_2 studied by high-resolution ARPES

    Shoman T., Takayama A., Sato T., Souma S., Takahashi T., Oguchi T., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　69　(2)　461-461　2014/08/22

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  38. 8aBF-4 High-resolution ARPES study of ultrathin Fe film

    Honma K., Tanaka Y., Sugawara K., Souma S., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　69　(2)　287-287　2014/08/22

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  39. 29pAQ-1 High-resolution ARPES study of oxygen-adsorbed Fe/VU(110) surface

    Honma K., Tanaka Y., Sugawara K., Souma S., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　69　(1)　898-898　2014/03/05

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  40. 28aBF-10 Electronic structure of topological crystalline insulator SnTe on two different surfaces

    Tanaka Y., Shoman T., Nakayama K., Souma S., Sato Y., Takahashi T., Novak M., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　69　(1)　707-707　2014/03/05

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  41. 28aBF-9 Electronic states of Bi-deposited TlBiSe2 studied by High-resolution ARPES

    Shoman T., Takayama A., Tanaka Y., Sugawara K., Souma S., Sato T., Takahashi T., Eto K., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　69　(1)　706-706　2014/03/05

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  42. 27pAQ-3 Edge state of Bi thin film studied by spin-resolved ARPES

    Takayama A., Sato T., Souma S., Oguchi T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　69　(1)　873-873　2014/03/05

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  43. ARPES study of new topological insulators and metal thin-films

    Souma Seigo

    Meeting abstracts of the Physical Society of Japan　68　(2)　630-630　2013/08/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  44. Anomalous electronic structure of Bi/Si(111) surface studied by high-resolution ARPES

    Takayama A., Sato T., Souma S., Oguchi T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　68　(2)　786-786　2013/08/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  45. Warping effect of Fermi surface in topological insulators studied by high-resolution ARPES

    Nomura M., Souma S., Eto K., Nakayama K., Sato T., Takahashi T., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　68　(2)　786-786　2013/08/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  46. Electronic structure of metal-atom-deposited TlBiSe_2 : High-resolution ARPES

    Shoman T., Tanaka Y., Sugawara K., Souma S., Sato T., Takahashi T., Eto K., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　68　(2)　786-786　2013/08/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  47. High-resolution ARPES study of topological crystalline insulator(Pb, Sn)Te

    Tanaka Y., Ren Z., Sato T., Nakayama K., Souma S., Takahashi T., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　68　(2)　605-605　2013/08/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  48. High-resolution ARPES study of Sn_<1-x>In_xTe, candidate of topological superconductor

    SatoA T., TanakaA Y., Nakayama K., Souma S., Takahashi T., Sasaki S., Ren Z., Taskin A.A., Segawac K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　68　(2)　605-605　2013/08/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  49. High-resolution ARPES study of Fe/W(110)

    Honma K., Tanaka Y., Sugawara K., Souma S., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　68　(2)　701-701　2013/08/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  50. High-resolution photoemission spectroscopy of Mg-Cu-Gd bulk metallic glass

    Souma S., Takahashi T., Madge S., Louzguine D.

    Meeting abstracts of the Physical Society of Japan　68　(2)　720-720　2013/08/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  51. 29aEJ-9 High-resolution ARPES study of W(110) surface

    Honma K., Tanaka Y., Sugawara K., Souma S., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　68　(1)　855-855　2013/03/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  52. 29aEJ-7 High-resolution ARPES study of metal-atom-adsorped topological-insulator surface

    Shoman T., Tanaka Y., Sugawara K., Souma S., Sato T., Takahashi T., Eto K., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　68　(1)　855-855　2013/03/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  53. 28pXG-5 Manipulation of Dirac-cone states with bulk heterostructure in topological insulators

    Nakayama K., Eto K., Tanaka Y., Sato T., Souma S., Takahashi T., Segawa Kouji, Ando Yoichi

    Meeting abstracts of the Physical Society of Japan　68　(1)　769-769　2013/03/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  54. 28pXG-3 Warping effect of Pb-based topological insulator studied by spin-resolved ARPES

    Nomura M., Souma S., Eto K., Nakayama K., Sato T., Takahashi T., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　68　(1)　768-768　2013/03/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  55. 28pXG-4 High-resolution ARPES study of topological crystalline insulator SnTe

    Tanaka Y., Ren Zhi, Sato T., Nakayama K., Souma S., Takahashi T., Segawa Kouji, Ando Yoichi

    Meeting abstracts of the Physical Society of Japan　68　(1)　769-769　2013/03/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  56. 18pFE-6 High-resolution spin-resolved ARPES study of Sb thin film

    Takayama A., Sato T., Souma S., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　67　(2)　815-815　2012/08/24

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  57. 20aFJ-12 Spin-dependent electronic states near the quantum phase transition of a Tl-based topological insulator

    Sato T., Souma S., Komatsu M., Nomura M., Takayama A., Takahashi T., Eto K., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　67　(2)　698-698　2012/08/24

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  58. 19pHB-5 Spin-resolved photoemission spectroscopy of advanced spintronics materials

    Souma Seigo

    Meeting abstracts of the Physical Society of Japan　67　(2)　694-694　2012/08/24

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  59. 20aFJ-13 Adsorbate-induced carrier-doping to surface states in topological insulator

    Komatsu M., Arakane T., Sato T., Souma S., Kosaka K., Nakayama K., Takahashi T., Ren Zhi, Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　67　(2)　699-699　2012/08/24

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  60. 20aEA-9 Spin-resolved ARPES study of TlBi(S, Se)_2

    Souma S., Komatsu M., Nomura M., Sato T., Takayama A., Takahashi T., Eto K., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　67　(2)　632-632　2012/08/24

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  61. 20aEA-8 Spin-resolved ARPES of topologcial insulator Pb(Bi_<1-x>Sb_x)_2Te_4

    Nomura M., Souma S., Eto K., Nakayama K., Sato T., Takahashi T., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　67　(2)　631-631　2012/08/24

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  62. Electronic structure of cement superconductor studied by high-resolution photoemission spectroscopy

    47　(5)　229-236　2012/05

    Publisher: アグネ技術センター

    ISSN： 0454-4544

  63. 24pCK-3 Film-thickness dependence of spin polarization of surface electronic states in Bi/Si(111) thin film

    Takayama A., Sato T., Souma S., Oguchi T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　67　(1)　939-939　2012/03/05

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  64. 26pBD-4 High-resolution ARPES study of Cu_xBi_2Se_3 : doping dependence of electronic sucture

    Tanaka Y., Nakayama K., Souma S., Sato T., Xu N., Zhang P., Ding H., Suzuki Y., Das P., Kadowaki K., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　67　(1)　740-740　2012/03/05

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  65. 25pBJ-5 Angle-resolved photoemission study of topological insulator Bi_<2-x>Sb_xTe_<3-y>Se_y

    Arakane T., Sato T., Souma S., Kosaka K., Nakayama K., Komatsu M., Takahashi T., Ren Z., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　67　(1)　733-733　2012/03/05

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  66. 25aBJ-5 High-resolution ARPES study of topological insulator Pb(Bl_<1-x>Sb_x)_2Te_4

    Souma S., Eto K., Nomura M., Nakayama K., Sato T., Takahashi T., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　67　(1)　728-728　2012/03/05

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  67. 27pYA-12 High-resolution ARPES study of electronic structure on LaCo_2B_2 superconductor

    Ieki E., Nakayama K., Umezawa K., Souma S., Sato T., Takahashi T., Kuroda M., Mizoguchi H., Kim S., Hosono H.

    Meeting abstracts of the Physical Society of Japan　67　(1)　697-697　2012/03/05

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  68. 27aAD-10 Development of high-resolution spin-resolved ARPES spectrometer and study on electronic structure of novel high-functional material

    Souma Seigo

    Meeting abstracts of the Physical Society of Japan　67　(1)　820-820　2012/03/05

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  69. 26pAD-3 Electronic structure of topological insulator Pb(Bi_<1-.x>Sb_x)_2Te_4 studied by high-resolution ARPES

    Nomura M., Eto K., Souma S., Nakayama K., Sato T., Takahashi T., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　67　(1)　810-810　2012/03/05

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  70. 高分解能スピン分解光電子分光装置の開発と表面ラシュバ効果の研究

    高山あかり, 相馬清吾, 高橋隆

    表面科学　33　165-171　2012

    DOI： 10.1380/jsssj.33.165 　

  71. 23pTR-11 Direct observation of z-spin component in Dirac-cone surface state of Bi_2Te_3 by spin-resolved ARPES

    Souma S., Kosaka K., Sato T., Komatsu M., Takayama A., Takahashi T., Kriener M., Segawa K., Ando Y.

    Meeting abstracts of the Physical Society of Japan　66　(2)　701-701　2011/08/24

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  72. 23pTR-4 Quantum phase transition of Tl-based topological insulator : high-resolution ARPES study

    Sato T., Segawa K., Kosaka K., Souma S., Nakayama K., Eto K., Minami T., Ando Y., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　66　(2)　699-699　2011/08/24

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  73. 23aHA-3 Dirac-cone topological surface states of TlBi(Se_xS_<1-x>)_2 studied by high-resolution ARPES

    Kosaka K., Eto K., Segawa K., Souma S., Sato T., Ando Y., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　66　(2)　927-927　2011/08/24

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  74. 23aHA-8 Anisotropic Rashba effect of Bi(111) thin film studied by high-resolusion spin-resolved ARPES

    Takayama A., Sato T., Souma S., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　66　(2)　929-929　2011/08/24

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  75. 22aTN-9 Dirac-cone surface states of thallium-based topological insulators studied by high-resolution ARPES

    Komatsu M., Eto K., Segawa K., Kosaka K., Souma S., Sato T., Ando Y., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　66　(2)　761-761　2011/08/24

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  76. 26aHB-8 High-resolution ARPES study of thallium-based topological insulators

    Komatsu M., Eto K., Segawa K., Kosaka K., Souma S., Sato T., Ando Y., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　66　(1)　769-769　2011/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  77. 26aTH-8 Anomalous Rashba effect of Bi(111) surface studied by high-resolusion spin-resolved ARPES

    Takayama A., Souma S., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　66　(1)　915-915　2011/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  78. 26aTH-1 Electronic structure of topological insulator TlBi(Se_xS_<1-x>)_2 studied by high-resolution ARPES

    Kosaka K., Eto K., Segawa K., Souma S., Sato T., Ando Y., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　66　(1)　913-913　2011/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  79. 26aHG-5 High-resolution ARPES study of new topological insulator TlBiSe_2

    Souma S., Segawa K., Sato T., Guo H., Sugawara K., Ando Y., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　66　(1)　707-707　2011/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  80. 25aWX-3 Spin-resolved electronic structure of Bi(111) surface

    Takayama A., Kosaka K., Sugawara K., Souma S., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　65　(2)　873-873　2010/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  81. 23pRG-2 Development of spin-resolved photoemission spectrometer based on mini-Mott detector: IV

    Souma S., Takayama A., Sugawara K., Guo H., Kosaka K., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　65　(2)　682-682　2010/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  82. 26aWJ-11 Anomalous electronic structure of CeSb : xenon-plasma-light ARPES

    Kosaka K., Takayama A., Souma S., Arakane T., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　65　(2)　620-620　2010/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  83. 24pRE-9 High-resolution ARPES study of Bi_<1-x>Sb_x(x=0.023)

    Guo H., Sugawara K., Takayama A., Souma S., Sato T., Sato N., Sasaki M., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　65　(2)　703-703　2010/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  84. 20pGH-1 Xenon-plasma-excited ARPES study of LaFeAsO

    Kawahara T., Umezawa K., Qian T., Guo H., Nakayama K., Richard P., Sato T., Souma S., Wang N. -L., Ding H., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　65　(1)　562-562　2010/03/01

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  85. 20pGQ-1 Ultrahigh-resolution spin-resolved ARPES study of Bi thin film

    Takayama A., Sugawara K., Souma S., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　65　(1)　931-931　2010/03/01

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  86. 21pGA-5 Fine Electronic Structure of Strongly Correlated Systems Observed by High-Resolution Photoemission Spectroscopy

    Souma S.

    Meeting abstracts of the Physical Society of Japan　65　(1)　756-756　2010/03/01

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  87. 21pGA-5 Fine Electronic Structure of Strongly Correlated Systems Observed by High-Resolution Photoemission Spectroscopy

    Souma S.

    Meeting abstracts of the Physical Society of Japan　65　(1)　621-621　2010/03/01

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  88. 23pGF-7 Xenon-plasma-light high-resolution PES study of CeRu_2Al_<10>

    Souma S., Arakane T., Takayama A., Takahashi T., Takesaka T., Sera M., Nishioka T.

    Meeting abstracts of the Physical Society of Japan　65　(1)　684-684　2010/03/01

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  89. 23pHL-9 Development of spin-resolved photoemission spectrometer based on mini-Mott detector: III

    Souma S., Takayama A., Sugawara K., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　65　(1)　811-811　2010/03/01

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  90. 25pRL-2 Doping Dependence of Superconducting Gap in Ba_<1-x>K_xFe_2As_2 : High-Resolution ARPES

    Kawahara T., Xu Y. -M., Richard P., Nakayama K., Sekiba Y., Qian T., Neupane N., Souma S., Sato T., Luo H., Wen H. -H., Chen G. -F., Wang N. -L., Fang Z., Dai X., Ding H., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　64　(2)　456-456　2009/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  91. 27aYG-4 Development of a mini-Mott spin detector and Rashba effect in surface electronic states of group-V semimetals

    Takayama A., Souma S., Sugawara K., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　64　(2)　834-834　2009/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  92. 27pYE-6 High-resolution ARPES study of high quality growth graphene

    Sugawara K., Takayama A., Souma S., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　64　(2)　783-783　2009/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  93. 26pXA-9 Development of spin-resolved photoemission spectrometer based on a mini-Mott detector: II

    Souma S., Takayama A., Sugawara K., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　64　(2)　636-636　2009/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  94. 30pTC-8 Fine electronic structure near the Fermi level of Ba_<1-x>K_xFe_2As_2 studied by high-resolution ARPES

    Nakayama K., Richard P., Sekiba Y., Sato T., Souma S., Neupane M., Xu Y.-M., Dai X., Fang Z., Chen G. F., Luo J. L., Wang N. L., Ding H., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　64　(1)　662-662　2009/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  95. 30pTC-9 Orbital-selective electron-mode coupling in optimally doped Ba_<0.6>K_<0.4>Fe_2As_2 : an ARPES investigation

    Richard P., Sato T., Nakayama K., Souma S., Xu Y.-M., Chen G. F., Luo J. L., Wang N. L., Ding H., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　64　(1)　662-662　2009/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  96. 30aVA-7 Temperature dependence of band structure in CeSb studied by Xenon-plasma-light high-resolution ARPES

    Takayama A., Souma S., Arakane T., Nakayama K., Sekiba Y., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　64　(1)　763-763　2009/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  97. 30aVA-10 Development of spin-resolved photoemission spectrometer based on mni-Mott detector

    Souma S., Takayama A., Mori T., Sugawara K., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　64　(1)　763-763　2009/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  98. 30aVA-2 Direct observation of superconducting gap in iron-based superconductor Ba_<1-x>K_xFe_2As_2 by ARPES

    Sato T., Ding H., Richard P., Nakayama K., Sugawara K., Arakane T., Sekiba Y., Takayama A., Souma S., Wang Z., Dai X., Fang Z., Chen G. F., Luo J. L., Wang N. L., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　64　(1)　761-761　2009/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  99. 28aYH-6 Sample growth and high-resolution ARPES study of single- and multi-layer graphene

    Ise K., Sugawara K., Takayama A., Souma S., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　64　(1)　828-828　2009/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  100. 角度分解光電子分光による鉄系超伝導体(Ba,K)Fe2As2の多重超伝導ギャップ

    佐藤宇史, Hong Ding, 相馬清吾, 高橋隆

    固体物理　43　(8)　499-506　2008/09

    Publisher: アグネ

  101. 20aYD-1 High-resolution ARPES study on Pb/Si(111)

    Mizuno K., Tago Y., Sun Yujie, Sugawara K., Souma S., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　63　(2)　619-619　2008/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  102. 20aYD-2 Electronic states of In-"1x1"/Si(111) : Temperature dependence

    Tago Y., Sun Yujie, Mizuno K., Sugawara K., Souma S., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　63　(2)　619-619　2008/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  103. 21aYG-8 Xenon-plasma-light high-resolution ARPES study of CeSb

    Takayama A., Souma S., Nakayama K., Sekiba Y., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　63　(2)　639-639　2008/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  104. 20pQE-10 Xenon-plasma-light ARPES study of pseudogap in Pb-substituted Bi2201

    Nakayama K., Sato T., Terashima K., Sekiba Y., Souma S., Takahashi T., Kudo K., Okumura N., Sasaki T., Kobayashi N.

    Meeting abstracts of the Physical Society of Japan　63　(2)　455-455　2008/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  105. 20aQF-10 Xenon-plasma-light high-resolution PES study of Yb_4As_3

    Souma S., Arakane T., Nakayama K., Takayama A., Sekiba Y., Sato T., Takahashi T., Ochiai A.

    Meeting abstracts of the Physical Society of Japan　63　(2)　444-444　2008/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  106. 20aYA-14 High-resolution photoemission study of La(O_<1-x>F_x)FeAs

    Sato T., Souma S., Nakayama K., Terashima K., Sugawara K., Takahashi T., Kamihara Y., Hirano M., Hosono H.

    Meeting abstracts of the Physical Society of Japan　63　(2)　448-448　2008/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  107. Bulk-sensitive high-resolution photoemission spectroscopy by xenon-plasma discharge lamp

    S. Souma, T. Sato, T. Takahashi

    Japanese Society of Applied Physics: Thin film and Surface Physics Division NEWS LETTER　132　27-33　2008/03/20

    Publisher: Japanese Society of Applied Physics: Thin film and Surface Physics Division

  108. 23aWR-4 Xenon-plasma-light high-resolution PES study of SmNiC_2

    Souma S., Nakayama K., Sato T., Takahashi T., Shimomura S., Onodera H.

    Meeting abstracts of the Physical Society of Japan　63　(1)　514-514　2008/02/29

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  109. 25pRH-12 Xenon-plasma-light high-resolution photoemission study of cement superconductor [Ca_<24>Al_<28>O_<64>]^4+(e^-)^4

    Arakane T., Souma S., Sato T., Takahashi T., Kim S.-W., Hosono H.

    Meeting abstracts of the Physical Society of Japan　63　(1)　617-617　2008/02/29

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  110. 26pTD-4 Temperature-dependent Fermi surface of In-"1x1"/Si(111)

    Tago Y., Sun Yujie, Sugawara K., Souma S., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　63　(1)　907-907　2008/02/29

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  111. 26aRH-4 Xenon-plasma-light ARPES study of superconducting gap and pseudogap in Bi2201

    Nakayama K., Sekiba Y., Terashima K., Souma S., Sato T., Takahashi T., Okumura N., Kudo K., Sasaki T., Kobayashi N.

    Meeting abstracts of the Physical Society of Japan　63　(1)　630-630　2008/02/29

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  112. 24pYH-3 ARPES study of kish graphite at 1000K

    Sugawara K., Nakayama K., Sato O., Souma S., Sato T., Takahashi T., Suematsu H.

    Meeting abstracts of the Physical Society of Japan　63　(1)　722-722　2008/02/29

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  113. 24pYH-5 Band structure of Pb ultra-thin film studied by high-resolution ARPES

    Sun Y.J., Tago Y., Sugawara K., Souma S., Sato T., Zhang Y.F., Xue Q.K., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　63　(1)　723-723　2008/02/29

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  114. 24aXK-6 High-resolution ARPES Study of Pb Ultra-thin Film

    Sun Y.J., Tago Y., Sugawara K., Souma S., Sato T., Zhang Y.F., Xue Q.K., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　62　(2)　964-964　2007/08/21

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  115. 21aTK-2 High-Resolution ARPES study of 1H-, 5H-.and 6H- CaAISi

    Xiao Y. X., Sugawara K., Souma S., Sato T., Takahashi T., Kamakura N., Kubota M., ono K., Kuroiwa S., Akimitsu J.

    Meeting abstracts of the Physical Society of Japan　62　(2)　718-718　2007/08/21

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  116. 21aTK-3 High-resolution ARPES study of ln-"1x1"/Si(111)

    Tago Y., Sun Yujie, Sugawara K., Souma S., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　62　(2)　718-718　2007/08/21

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  117. 24aWG-2 Xenon-plasma-light bulk-sensitive ultrahigh-resolution photoemission study of Bi2201

    Nakayama K., Sato T., Terashima K., Souma S., Takahashi T., Okumura N., Kudo K., Sasaki T., Kobayashi N.

    Meeting abstracts of the Physical Society of Japan　62　(2)　648-648　2007/08/21

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  118. 22aWF-12 Xenon-plasma-light bulk-sensitive ultrahigh-resolution photoemission study of Co (S_<1-x>S_x)_2

    Sato T., Souma S., Sugawara K., Nakayama K., Raj Satyabrata, Hiraka H., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　62　(2)　583-583　2007/08/21

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  119. 18aWF-8 Superconducting gap of La_2C_3 : ultrahigh-resolution PES

    Sugawara K., Sato T., Souma S., Takahashi T., Ochiai A.

    Meeting abstracts of the Physical Society of Japan　62　(1)　488-488　2007/02/28

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  120. 20pZA-9 ARPES Studies of Metal-Insulator Transition on In(4×1)/Si(111)

    Agario S., Sun Y. J., Sugawara K., Kondo G., Tago Y., Souma S., Sato T., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　62　(1)　746-746　2007/02/28

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  121. 18aWF-2 Superstructure-dependence of electronic states in CaAlSi studied by high-Resolution ARPES

    Xiao Y. X, Sugawara K, Nakajima Y, Souma S, Sato T, Takahashi T, Kubota M, Ono K, Kuroiwa S, Akimitsu J

    Meeting abstracts of the Physical Society of Japan　62　(1)　487-487　2007/02/28

    Publisher: 一般社団法人日本物理学会

    ISSN： 1342-8349

  122. 24aYA-10 Fine structure of Fermi surface in Ce_2TIn_8 (T=Co, Rh, Ir)

    Souma S., Raj S., Terashima K., Campuzano J.C., Takahashi T., Ohara S., Sakamoto I.

    Meeting abstracts of the Physical Society of Japan　61　(2)　433-433　2006/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  123. 24pZR-15 Electronic structure of A_xWO_3(A=K,Na): High-resolution ARPES studies

    Raj S., Souma S., Matsui H., Sato T., Takahashi T., Sarma D.D., Mahadevan P., McCarroll W.H., Greenblatt M., Ohishi S.

    Meeting abstracts of the Physical Society of Japan　61　(2)　481-481　2006/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  124. 26aZR-10 High-resolution ARPES study of RAgSb_2(R=La,Ce)

    Sato T., Arakane T., Souma S., Takahashi T., Watanabe Y., Inada Y.

    Meeting abstracts of the Physical Society of Japan　61　(2)　519-519　2006/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  125. 26aZB-5 Anomaly of π band Fermi surface of graphite : high-resolution ARPES

    Sugawara K., Souma S., Sato T., Takahashi T., Suematsu H.

    Meeting abstracts of the Physical Society of Japan　61　(2)　709-709　2006/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  126. 29pRE-2 Many body interaction of kish graphite studied by ultrahigh-resolution ARPES

    Sugawara K., Sato T., Souma S., Takahashi T., Suematsu H.

    Meeting abstracts of the Physical Society of Japan　61　(1)　753-753　2006/03/04

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  127. Shadow bands in single-layered Bi2 Sr2 Cu O6+δ studied by angle-resolved photoemission spectroscopy

    K. Nakayama, T. Sato, T. Dobashi, K. Terashima, S. Souma, H. Matsui, T. Takahashi, J. C. Campuzano, K. Kudo, T. Sasaki, N. Kobayashi, T. Kondo, T. Takeuchi, K. Kadowaki, M. Kofu, K. Hirota

    Physical Review B - Condensed Matter and Materials Physics　74　(5)　054505　2006

    DOI： 10.1103/PhysRevB.74.054505 　

    ISSN： 1098-0121

    eISSN： 1550-235X

  128. 20aYJ-5 High-resolution ARPES study of A_xWO_3(A:Alkali metal)

    Hashimoto D., Raj S., Matsui H., Ray S., Sarma D. D., Souma S., Sato T., Takahashi T., Ohishi S., McCarroll W. H., Greenbalatt M.

    Meeting abstracts of the Physical Society of Japan　60　(2)　427-427　2005/08/19

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  129. 21pXD-11 Doping dependence of electronic structure in Na_xCoO_2 studied by ARPES

    Sato T., Dobashi T., Yang H. -B., Wang S. -C., Ding H., Soma S., Matsui H., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　60　(2)　486-486　2005/08/19

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  130. 21pYD-11 High-resolution ARPES study of insulating Na_xWO_3 : Anderson localization(English Session of Division 5)

    Raj S., Hashimoto D., Matsui H., Ray S., Sarma D. D., Souma S., Sato T., Takahashi T., Ohishi S.

    Meeting abstracts of the Physical Society of Japan　60　(2)　618-618　2005/08/19

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  131. 19pYD-2 Observation of anisotropic spin-orbit coupling in Sb(111) by high-resolution ARPES

    Sugawara K., Sato T., Souma S., Arai M., Sasaki T., Kubota M., Ono K., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　60　(2)　571-571　2005/08/19

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  132. 22pXF-9 High-resolution ARPES study of Sb(111) surface : electron-phonon interaction

    Sugawara K., Sato T., Souma S., Takahashi T., Arai M., Sasaki T.

    Meeting abstracts of the Physical Society of Japan　60　(2)　789-789　2005/08/19

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  133. 22pXF-8 High-resolution ARPES study of Sb(111) surface : band structure and Fermi surface

    Sugawara K., Sato T., Souma S., Takahashi T., Arai M., Sasaki T.

    Meeting abstracts of the Physical Society of Japan　60　(2)　789-789　2005/08/19

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  134. 25pWF-10 Many-body interaction in Na_xCoO_2 studied by high-resolution ARPES

    Sato T., Dobashi.T., Yang H.-B., Wang S.-C., Drig H., Souma S., Matsui H., Takahashi T.

    Meeting abstracts of the Physical Society of Japan　60　(1)　560-560　2005/03/04

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  135. 25aXQ-6 Electronic structure near the Fermi level of kish graphite

    Souma S., Sato T., Takahashi T., Suematsu H.

    Meeting abstracts of the Physical Society of Japan　60　(1)　694-694　2005/03/04

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  136. 24pXP-7 CBand sturucture of Ce_2TIn_8 (T=Co,Rh) : high-resolution ARPES

    Iida Y., Raj S., Souma S., Sato T., Takahashi T., Harima H., Hayakawa T., Ohara H., Sakamoto I.

    Meeting abstracts of the Physical Society of Japan　60　(1)　685-685　2005/03/04

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  137. 24pXP-8 Doping dependence of the electronic structure in Na_xWO_3 studied by angle-resolved photoemission spectroscopy

    Hashimoto D., Ray S., Matsui H., Sarma D. D., Souma S., Sato T., Takahashi T., Ohishi S., McCarroll W. H., Greenblatt M.

    Meeting abstracts of the Physical Society of Japan　60　(1)　685-685　2005/03/04

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  138. 25aXQ-5 Electron-phonon interaction in Sb(111) surface ; high-resolution ARPES

    Sugawara K., Ono K., Sato T., Souma S., Takahashi T., Arai M., Sasaki T.

    Meeting abstracts of the Physical Society of Japan　60　(1)　694-694　2005/03/04

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  139. 24pWF-13 ARPES studies on highly metallic sodium tungsten bronzes Na_xWO_3

    Raj S, Hashimoto, Matsui H, Ray S, Sarma D, Souma S, Sato T, Takahasni T, Ohishi S, McCarrall W H, Greenblatt M

    Meeting abstracts of the Physical Society of Japan　60　(1)　507-507　2005/03/04

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  140. 12pTM-3 Coexistence/Competition between Superconductivity and Charge-Density Wave in Quasi-1D Conductors Nb_3Xc_4 (Xc=S, Se, Te) Studied by High-Resolution ARPES

    Dobashi T., Sato T., Souma S., Takahashi T., Ishihara Y.

    Meeting abstracts of the Physical Society of Japan　59　(2)　699-699　2004/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  141. 12aXC-9 Metal-Insulator Transition of Na_xWO_3 studied by high-resolution photoemission spectroscopy

    Hashimoto D., Raj S., Matsui H., Ray S., Sarma D. D., Souma S., Sato T., Takahashi T., Ohishi S., McCarroll W. H., Greenblatt M.

    Meeting abstracts of the Physical Society of Japan　59　(2)　629-629　2004/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  142. 12aXC-2 Band structure and Fermi surface of Sb(111) surface studied by ARPES

    Sugawara K., Sato T., Souma S., Takahashi T., Arai M., Sasaki T.

    Meeting abstracts of the Physical Society of Japan　59　(2)　628-628　2004/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  143. 12aXC-7 Direct observation of band folding induced by charge-density waves in RTe_3 (R=Rare earth) studied by ARPES

    Komoda H., Souma S., Sato T., Takahashi T., Ito Y., Suzuki K.

    Meeting abstracts of the Physical Society of Japan　59　(2)　629-629　2004/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  144. 12aXC-10 Band Structure and Fermi surface of Na_xWO_3

    Raj S., Hashimoto D., Matsui H., Ray S., Sarma D. D., Souma S., Sato T., Takahashi T., Ohishi S., McCarroll W. H., Greenblatt M.

    Meeting abstracts of the Physical Society of Japan　59　(2)　630-630　2004/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  145. 12aXC-1 Observation of edge state in kish graphite by high-resolution ARPES

    Takahashi T., Sato T., Souma S., Suematsu H.

    Meeting abstracts of the Physical Society of Japan　59　(2)　627-627　2004/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  146. 14pRC-4 X-ray angle-resolved photoemission study of AlB_2

    Souma S, Iida Y, Sato T, Takahashi T, Kimura N, Aoki H

    Meeting abstracts of the Physical Society of Japan　59　(2)　532-532　2004/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  147. 13aRD-9 High-resolution ARPES study of Ce_2TIn_8 (T=Co, Rh)

    Iida Y, Souma S., Sato T, Takahashi T, Hayakawa T, Ohhara S., Sakamoto I.

    Meeting abstracts of the Physical Society of Japan　59　(2)　456-456　2004/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  148. 13aRC-10 Doping dependence of band structure and Fermi surface of Na_xCoO_2 studied by high-resolution ARPES

    Sato T, Yang H-B, Wang S-C, Ding H, Souma S, Matsui H, Takahashi T

    Meeting abstracts of the Physical Society of Japan　59　(2)　453-453　2004/08/25

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  149. 28pXC-3 High-resolution angle-resolved photoemission study of Na_xCoO_2

    Sato T, Yang H -B, Wang S -C, Sekharan A K P, Ding H, Matsui H, Souma S, Takahashi T, Takeuchi T, Campuzano J C, Jin R, Sales B C, Mandrus D, Wang Z

    Meeting abstracts of the Physical Society of Japan　59　(1)　589-589　2004/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  150. 30aXD-7 Superconducting gap of YB_6 : ultrahigh-resolution photoemission spectroscopy

    Souma S., Iida Y., Sato T., Takahashi T., Kunii S.

    Meeting abstracts of the Physical Society of Japan　59　(1)　644-644　2004/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  151. 28pWN-5 Fine electronic structure of kish graphite : Ultrahigh-resoultion ARPES

    Takahashi T., Sato T., Souma S., Suematsu H.

    Meeting abstracts of the Physical Society of Japan　59　(1)　854-854　2004/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  152. 29pXD-15 High-resolution Angle-resolved photoemission study of Ce_2CoIn_8

    Iida Y, Souma S, Sato T, Takahashi T, Hayakawa T, Ohhara S, Sakamoto I

    Meeting abstracts of the Physical Society of Japan　59　(1)　630-630　2004/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  153. 27pYD-5 Angle-resolved photoemission study of RTe_3(R=La,Ce)

    Komoda H., Souma S., Komatsu H., Sato T., Takahashi T., Ito Y., Suzuki K.

    Meeting abstracts of the Physical Society of Japan　59　(1)　801-801　2004/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  154. 27aXB-8 Electronic structure and superconducting gap of ZrRuP : Ultrahigh-resolution photoemission spectroscopy

    Hashimoto D, Matsui H, Souma S, Sato T, Takahashi T, Shirotani I

    Meeting abstracts of the Physical Society of Japan　59　(1)　512-512　2004/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  155. 27aXQ-13 Electronic structure of CeTe_3 and LaTe_3 studied by angle-resolved photoemission spectroscopy

    Komatsu H., Souma S., Komoda H., Sato T., Takahashi T., Ito Y., Suzuki K.

    Meeting abstracts of the Physical Society of Japan　59　(1)　716-716　2004/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  156. 28pXE-7 Three dimensional topology of band structure in (Bi_2,Pb_2)Sr_2CuO_<6+δ>

    Kondo T, Kimura S, Takeuchi T, Mizutani U, Ding Hong, Campuzano J C, Souma S, Iida Y, Ito T

    Meeting Abstracts of the Physical Society of Japan　59　(0)　595-595　2004

    Publisher: 一般社団法人 日本物理学会

    ISSN： 1342-8349

  157. 角度分解光電子分光によるMgB2多重ギャップの起源

    相馬清吾, 高橋 隆

    Forum of Superconductivity Science and Technology News　(99)　4-7　2003/09/15

  158. Fermi surface and band structure of (Ce, La)Rh_3B_2 : angle-resolved photoemission spectroscopy

    Souma S., Iida Y., Sato T., Takahashi T., Yamada M., Okubo T., Shiromoto T., Inada Y., Settai R., Onuki Y.

    Meeting abstracts of the Physical Society of Japan　58　(2)　565-565　2003/08/15

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  159. Bulk electronic structure of CaB_6 studied by x-ray ARPES

    Souma S., Komatsu H., Matsui H., Sato T., Takahashi T., Muro T., Kimura N., Aoki H., Kunii S., Akimitsu J.

    Meeting abstracts of the Physical Society of Japan　58　(2)　635-635　2003/08/15

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  160. Band dispersion and Fermi surface of 1T-VSe_2 studied by angle-resolved photoemission spectroscopy

    Terashima K., Souma S., Sato T., Takahashi T., Maeda N., Hayashi K.

    Meeting abstracts of the Physical Society of Japan　58　(2)　635-635　2003/08/15

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  161. High-resolution angle-resolved photoemission study of RRh_3B_2 (R=La, Ce)

    Iida Y., Souma S., Sato T., Yamada M., Okubo T., Shiromoto T., Inada Y., Settai R., Onuki Y.

    Meeting abstracts of the Physical Society of Japan　58　(2)　636-636　2003/08/15

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  162. X-ray angle-resolved photoemission spectroscopy on CaB_6

    Souma S., Takahashi T., Komatsu H., Matsui H., Sato T., Muro T., Kimura N., Aoki H., Kunii S., Akimitsu J.

    Meeting abstracts of the Physical Society of Japan　58　(1)　402-402　2003/03/06

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  163. Superconducting gaps of MgB_2 : Angle-resolved photoemission spectroscopy

    Souma S, Kakeya I, Sasaki S, Kadowaki K, Machida Y, Takahashi T, Sato T, Matsui H, Wang S. C, Ding H, Kaminski A, Campuzano J. C

    Meeting Abstracts of the Physical Society of Japan　58　(0)　491-491　2003

    Publisher: The Physical Society of Japan

    ISSN： 1342-8349

  164. Angle-resolved photoemission spectroscopy of CeB6

    Souma S., Takahashi T., Kumigashira H., Oshima M., Kunii S.

    Meeting abstracts of the Physical Society of Japan　57　(2)　594-594　2002/08/13

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  165. Angle-resolved photoemission spectroscopy of AlB2

    Souma S, Sato T, Takahashi T, Kimura N, Aoki H

    Meeting abstracts of the Physical Society of Japan　57　(2)　525-525　2002/08/13

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  166. 24aXF-6 Fermi surface and band dispersion of CaB_6; High-resolution ARPES

    Souma S., Komatsu H., Takahashi T., Kaji R, Yokoo T., Akimitsu J.

    Meeting abstracts of the Physical Society of Japan　57　(1)　368-368　2002/03/01

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  167. 27pWB-14 study of magnteiSc Pig transifon in UXc (Xc=, Se, Te)

    Ito T., Kumigashira H., Souma S., Takahashl T, Ochiai A

    Meeting abstracts of the Physical Society of Japan　57　(1)　592-592　2002/03/01

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  168. 27pWB-15 "Heavy" Fermi surface of a layerd material UAs_2 studied by UHR-ARPFS

    Kumigashira H., Ito T., Souma S., Takahashi T., Aoki D., Onuki Y.

    Meeting abstracts of the Physical Society of Japan　57　(1)　592-592　2002/03/01

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  169. 25aYD-6 High-resolution photoemission spectroscopy on UXp (Xp=J, As, Sb)

    Ito T., Kumigashira H., Souma S., Takahashi T., Ochiai A.

    Meeting abstracts of the Physical Society of Japan　57　(1)　677-677　2002/03/01

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  170. 25aYD-7 Photoemission spectroscopy of high temperature ferromagnet CaB6

    Komatsu H., Souma S., Takahashi T., Kaji R., Yokoo T., Akimitsu J.

    Meeting abstracts of the Physical Society of Japan　57　(1)　678-678　2002/03/01

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  171. High-resolution angle-resolved photoemission spectroscopy on UXc(Xc=S, Se, Te)

    Ito T., Kumigashira H., Souma S., Takahashi T., Ochiai A.

    Meeting abstracts of the Physical Society of Japan　56　(2)　621-621　2001/09/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  172. Ultrahigh-resolution photoemission spectroscopy on UGe_2

    Ito T., Kumigashira H., Souma S., Takahashi T., Haga Y., Onuki Y.

    Meeting abstracts of the Physical Society of Japan　56　(2)　495-495　2001/09/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  173. "Heavy" Fermi surface of a layered material USb_2 studied by UHR-ARPES

    Kumigashira H., Ito T., Souma S., Takahashi T., Aoki D., Ounuki Y.

    Meeting abstracts of the Physical Society of Japan　56　(2)　495-495　2001/09/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  174. High-resolutlon photoemission spectroscopy of Ca_<1-x>La_xB_6 (x=0.005)

    Souma S., Kumigashira H., Ito T., Takahashi T., Umeda Y., Kimura N., Aoki H.

    Meeting abstracts of the Physical Society of Japan　56　(2)　373-373　2001/09/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  175. Band Structure and Fermi Surface of UC Studied by Ultrahigh-Resolution Angle-Resolved Photoemission Spectroscopy

    Ito T., Kumigashira H., Souma S., Takahashi T., Yamamoto E., Haga Y., Onuki Y.

    Meeting abstracts of the Physical Society of Japan　56　(1)　445-445　2001/03/09

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  176. Ultrahigh-Resolution Photoemission Study of Kondo Insulators CeRhSb, CeRhAs, and SmB_6

    Kumigashira H., Souma S., Ito T., Takahashi T., Yoshii S., Kasaya M., Kunii S.

    Meeting abstracts of the Physical Society of Japan　56　(1)　668-668　2001/03/09

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  177. Direct Observation of Pusedo-gap in Sm_6 using Ultra-high Resolution Photoemission

    Souma S., Kumigashira H., Ito T., Takahashi T., Kunii S.

    Meeting abstracts of the Physical Society of Japan　56　(1)　565-565　2001/03/09

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  178. Band Structure and Fermi Surface of DyB_2C_2 Studied by Angle-Resolved Photoemission Spectroscopy

    Souma S., Kumigashira H., Ito T., Nakai T., Takahashi T., Yamauchi H., Onodera H., Yamaguchi Y.

    Meeting abstracts of the Physical Society of Japan　55　(2)　540-540　2000/09/10

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  179. Fermi Surface of UPd_3 Studied by Ultrahigh-Resolution Angle-Resolved Photoemission

    Ito T., Kumigashira H., Souma S., Takahashi T., Tokiwa Y., Haga Y., Onuki Y.

    Meeting abstracts of the Physical Society of Japan　55　(2)　510-510　2000/09/10

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  180. Ultrahigh-Resolution Angle-Resolved Photoemission Study of Layer Compound USb_2

    Kumigashira H., Ito T., Souma S., Takahashi T., Aoki D., Onuki Y.

    Meeting abstracts of the Physical Society of Japan　55　(2)　511-511　2000/09/10

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  181. Photoemission spectroscopy of CaB_6 : Test for exitonic insulator model

    Souma S., Kumigashira H., Ito T., Takahashi T., Kunii S.

    Meeting abstracts of the Physical Society of Japan　55　(2)　422-422　2000/09/10

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  182. High-Resolution Angle-Resolved Photoemission Spectroscopy of UC

    Ito T., Kumigashira H., Souma S., Takahashi T., Yamamoto E., Haga Y., Onuki Y.

    Meeting abstracts of the Physical Society of Japan　55　(1)　449-449　2000/03/10

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  183. High-Resolution Angle Resolved Photoemission Study of UN

    Kumigashira H., Ito T., Souma S., Nakai N., Takahashi T., Suzuki T.

    Meeting abstracts of the Physical Society of Japan　55　(1)　448-448　2000/03/10

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  184. Ultrhigh-resolution photoemission study of CePd_3

    Souma S., Kumigashira H., Ito T., Nakai T., Takahashi T., Kasaya M.

    Meeting abstracts of the Physical Society of Japan　55　(1)　464-464　2000/03/10

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  185. 26aJ-3 Direct observation of crstal-field splittng in CeB_6 by ultrahigh-resolution photoemission

    Souma S, Sato T, Kamiyama T, Naitoh H, Kumigashira H, Takahashi T, Kunii S

    Meeting abstracts of the Physical Society of Japan　54　(2)　541-541　1999/09/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

Show all ︎Show first 5

Books and Other Publications 2

  1. 放射光利用の手引き : 農水産・医療、エネルギー、環境、材料開発分野などへの応用

    東北放射光施設推進会議推進室

    アグネ技術センター　2019/02

    ISBN: 9784901496957

  2. X線光電子分光法 (分光法シリーズ 第 6巻)

    高桑 雄二

    講談社　2018/12/22

    ISBN: 4065140471

Presentations 40

  1. Micro- and nano-focused ARPES on antiferromagnet Invited

    Seigo Souma

    Second Workshop on the Chicago-Tohoku Quantum Alliance　2025/05/16

  2. Spin-resolved ARPES of topological insulators using laboratory-based light sources Invited

    Seigo Souma

    2024 MBS Summer Workshop　2024/06/15

  3. 反強磁性トポロジカル絶縁体における電子構造の磁気ドメイン分割観察 Invited

    相馬清吾

    東北大学電気通信研究所 共同プロジェクト研究会　2023/03/03

  4. マイクロAPRESによる反強磁性トポロジカル物質のドメイン分割観測 Invited

    相馬清吾

    スピントロニクス学術研究基盤と連携ネットワーク（Spin-RNJ）」シンポジウム　2022/03/10

  5. 反強磁性トポロジカル絶縁体のディラック電子状態:マイクロARPES Invited

    相馬清吾

    東北大学電気通信研究所 共同プロジェクト研究会　2022/01/28

  6. 軟X線ARPESによるスピントロニクス材料の物性機能解明 Invited

    相馬 清吾

    日本物理学会 領域5, 領域3 合同シンポジウム 「次世代スピントロニクスに向けた軟X線放射光計測技術の発展」　2019/09/11

  7. 電子状態解析に基づくトポロジカル物質相の探索

    相馬 清吾

    新学術領域 「次世代物質探索のための離散幾何学」領域研究会　2019/08/03

  8. トポロジカル半金属のバルクノード構造と表面電子状態:ARPES Invited

    相馬 清吾

    第11回トポロジー連携研究会 「トポロジカル半金属」　2019/08/02

  9. New topological phases protected by ΘT symmetry Invited

    Seigo Souma

    AIMR Workshop on Quantum Materials and Spintronics: Spin, Topology and Superconductivity　2019/06/12

  10. Direct observation of nodal fermions in topological semimetals Invited

    Seigo Souma

    MANA International Symposium 2019　2019/03/05

  11. ARPES observation of nodal fermions in topological semimetals Invited

    Seigo Souma

    2nd Tohoku/SG-SPIN workshop in spintronics　2019/02/24

  12. 強磁性トポロジカル絶縁体の電子構造:ARPES

    相馬 清吾

    第２回スピントロニクス学術研究基盤と連携ネットワークシンポジウム　2019/02/20

  13. ナノARPESの現状と次世代放射光での展開

    相馬 清吾

    第５回放射光連携研究ワークショップ「先端計測とインフォマティクスによる可視化物質科学の発展」　2019/02/09

  14. ARPES Observation of Various Types of New Topological Semimetals

    Seigo Souma

    トポロジカル物質科学第４回領域研究会　2019/01/23

  15. Three dimensional topological semimetals Invited

    Seigo Souma

    Nano-Spin Conversion Science, One-day Symposium on Spintronic Properties of Graphene and Related 2D Materials　2018/11/22

  16. 世界の3-GeV放射光におけるスピン/ナノARPESの現状

    相馬 清吾

    放射光を用いたナノスピン材料科学の新展開　2018/10/05

  17. 高分解能ARPESで見たトポロジカル半金属の電子構造 Invited

    新学術領域TMS第二回領域研究会　2016/12/16

  18. Electronic band structure near the Fermi level of (Ga,Mn)As: High-resolution in-situ ARPES International-presentation Invited

    14th RIEC International Workshop on Spintronics　2016/11/17

  19. Valence-band electronic structure of (Ga,Mn)As studied by high-resolution ARPES

    第77回応用物理学会秋季学術講演会　2016/09/13

  20. (Ga,Mn)Asのin-situ高分解能ARPES

    日本物理学会 2016年秋季大会　2016/09/13

  21. ワイル半金属候補物質NbPの表面フェルミアーク：高分解能ARPES

    日本物理学会 第71回年次大会　2016/03/19

  22. Fe/W(110)界面におけるディラックコーン電子状態の 磁気的近接効果：高分解能ARPES Invited

    第20回スピンに関連した物理とデバイスに関する国内会議　2015/12/03

  23. ワイル半金属候補物質の高分解能ARPES Invited

    相馬清吾

    新学術領域「トポロジーが紡ぐ物質科学のフロンティア」第５回トポロジー連携集中研究会「ワイル半金属・超伝導体」　2015/11/06

  24. Direct observation of spin in materials by photoemission spectroscopy Invited

    Seigo Souma

    12th Japanese-German Frontiers of Science (JGFoS) Symposium　2015/10/01

  25. Topological Insulators Studied by Spin-Resolved ARPES International-presentation Invited

    Seigo Souma

    The International Conference on Materials for Advanced Technologies 2015　2015/06/26

  26. スピン分解ARPESで探る３次元トポロジカル絶縁体の電子構造 Invited

    相馬清吾

    多元物質科学研究所 若手交流講演会～若手研究者が語る放射光を使った材料分析～　2015/01/23

  27. Spin-resolves ARPES of three-dimensional topological insulators International-presentation Invited

    Seigo Souma

    Condensed Matter Seminar, Ames laboratory　2014/10/30

  28. スピン分解ARPESで見たトポロジカル絶縁体の表面電子状態 Invited

    相馬清吾

    第59回物性若手夏の学校　2014/07/31

  29. Spin-helical Dirac-cone surface states of 3D topological materials International-presentation

    AIMR/UCL Materials Workshop.　2013/11/21

  30. Spin-resolved ARPES on topological insulators Invited

    Seigo Souma

    AIMR workshop “Topological Functional Materials;Devices”　2012/12/01

  31. Topological quantum phase transition of TlBi(S1-xSex)2 studied by ARPES Invited

    Seigo Souma

    International workshop for young researchers in topological quantum phenomena in condensed matter with broken symmetry　2012/11/03

  32. Anomalous Dirac-cone state of three-dimensional topological insulator revealed by high-resolution spin ARPES Invited

    Seigo Souma

    UCSB ICMR/CNSI and Toholu University WPI-AIMR joint workshop on material research　2012/01/11

  33. Ultrahigh-resolution spin-resolved ARPES of novel low-dimensional systems Invited

    Seigo Souma

    Electronic, Transport, and Optical properties of low-dimensional systems　2010/06/01

  34. Spin-resolved ultrahigh-resolution ARPES study of Rashba effect on group-V semimetal surface Invited

    Seigo Souma

    The 14th Hiroshima international Symposium on Synchrotron Radiation　2010/03/04

  35. Development of bulk-sensitive spin-resolved ultrahigh-resolution photoemission spectrometer Invited

    Seigo Souma

    LEPES2009 (UVSOR Workshop on Low-Energy Photoemission of Solids using Synchrotron Radiation),　2009/10/03

  36. High-resolution ARPES of novel superconductors Invited

    Seigo Souma

    Fudan-Tohoku joint workshop　2008/11/14

  37. キセノンプラズマ発光によるセメント超伝導体[Ca24Al28O64]4+(e-)4の高分解能光電子分光

    日本物理学会 63回年次大会　2008/03/23

  38. Band structure and Fermi surface of heavy Fermion compounds Ce2TIn8 (T=Co,Rh,In) studied by angle-resolved photoemission spectroscopy International-presentation

    The International Conference on Strongly Correlated Electron Systems　2007/05/13

  39. Anomalous electronic states of graphite and related materials International-presentation Invited

    Seigo Souma

    Strong Correlations and Angle-Resolved Photoemission Spectroscopy　2007/04/10

  40. Ce2TIn8(T=Rh，Co，Ir)のフェルミ面微細電子構造

    日本物理学会 2006年秋季大会　2006/09/23

Show all Show first 5

Research Projects 16

  1. Search for new topological materials by spin-resolved nano-ARPES

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (A)

    Institution: Tohoku University

    2025/04/01 - 2029/03/31

  2. Observation of chiral edge state in magnetic topological material by nono-spin ARPES

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: Tohoku University

    2024/04 - 2027/03

  3. Multidisciplinary analysis of oxide devices and interfaces using the international network of next generation synchrotron-radiation facilities

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Fund for the Promotion of Joint International Research (Fostering Joint International Research (B))

    Institution: Tohoku University

    2020/10 - 2026/03

  4. Search for exotic quasiparticles by angle-resolved photoemission spectroscopy

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (A)

    Institution: Tohoku University

    2021/04/05 - 2025/03/31

  5. Development of 2D electron spin detector and research of ferromagnetic topological insulator Competitive

    Souma Seigo

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: Tohoku University

    2019 - 2021

    More details Close

    restWe have performed high-resolution ARPES study on ferromagnetic topological insulator (CrxSb1-x)2Te3, and revealed a clear Cr-doping dependence of the Fermi surface. The density of states estimated from the experimental results, we concluded that the RKKY interaction is a main cause of carrier induced ferromagnetism in topological insulator. Furthermore, we observed a distinct change in the surface Dirac electron states across the Curie temperature, attributing it to a significant magnetic gap about 100 meV above EF. We have also succeeded in domain-selective ARPES on NdBi. We found that the surface Dirac cone states shows clear energy gap depending on the domain. This experimentally establishes that NdBi is the antiferromagnetic topological insulator.

  6. Superconductivity and spin-orbit interaction in atomically thin films studied by ARPES Competitive

    Sato Takafumi

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (A)

    Institution: Tohoku University

    2017 - 2020

    More details Close

    We have investigated new types of atomic-layer materials based on the understanding of energy band structure in the vicinity of the Fermi level responsible for the physical properties, by integrating high-resolution spin-resolved ARPES technique and fabrication of high-quality ultrathin films using molecular-beam epitaxy. In transition-metal dichalcogenides (TMDs), we fabricated some new monolayer compounds and accurately elucidated their unusual electronic states such as the energy gap. We also proposed a new method to control dimensionality of the TMDs. Moreover, we found Dirac electrons in the iron-based-superconductor thin films and hybrid thin films involving topological insulators and Rasha metals, and found that its appearance is governed by a few key parameters such as the spin-orbit interactions and crystal symmetry.

  7. 電子状態解析に基づくトポロジカル物質相の探索 Competitive

    相馬清吾

    Offer Organization: 日本学術振興会

    System: 科学研究費補助金 新学術領域研究

    Category: 新学術領域研究(研究領域提案型)

    Institution: 東北大学

    2018 - 2019

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    ARPES実験の更なる高精度・高効率化、また将来のpump-probe実験のための準備として、準CWレーザー光源の立ち上げとAREPS装置への導入を行なった。ARPES装置の電子フォーカス点の許容誤差は励起光のスポットがスリットと同程度以下(典型的には0.2 mm)となると大変厳しくなることから、測定時の試料の３次元座標を厳密に保つために、試料のモニタリングシステムを導入し試料位置制御の高精度化した。さらに、レーザー出力と試料上のスポットの高安定化のために、共鳴成分の監視システム、光学調整機構の可視化・自動化、湿度対策、清浄化対策、振動対策などを行い、装置全体の性能を向上させた。以上の結果、微小試料においてARPESバンド測定の空間依存性などの実験に成功することができた。 これら装置開発と並行して、トポロジカル半金属や関連物質について、高分解能ARPES実験を行った。線ノード型のトポロジカル半金属の表面バンドについて確立する目的で、結晶構造にグライド対称性をもつZrGeXc(Xc=S,Se,Te)において軟X線AREPS実験を行い、３次元バルク線ノード構造の観測に成功した。さらに高分解能ARPES実験の結果、全ての物質において共通して表面Dirac-node-arc電子バンドを観測した。以上の結果から、この表面状態が結晶のもつグライド対称性に起因したトポロジカルな電子状態であるとの示唆を得た。また、超伝導秩序と表面ディラック電子状態の関わりを調べるために、３次元トポロジカル絶縁体TlBiSe2の上に超伝導Pb薄膜を成長させ高分解能ARPES実験を行なった結果、Pbの量子化井戸準位がTlBIiSe2の表面バンドと混成し、さらに超伝導相において超伝導ギャップを形成することを見出した。

  8. Development of functional ultra-thin film hybrid based on spin-resolved ARPES Competitive

    Takashi Takahashi

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (A)

    Institution: Tohoku University

    2015 - 2017

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    We constructed a complex spin-resolved ARPES system with a multi-component MBE system to achieve the following three targets; (1) exploring the electronic structure of novel functional materials, (2) strategic development of advanced new materials based on the determined electronic structure, and (3) creating novel functions by making a hybrid of different materials. Using this ARPES system, we have succeeded in creating several new materials/functions as well as improving their novel properties. Some representative achievements are realization of high-Tc superconductivity in atomically thin FeSe, fabrication of superconducting bilayer graphene with intercalation method, synthesis of trilayer graphene with selecting the stacking sequence and identification of the electronic structure, control and tuning of electronic structure in atomically thin transition-metal dichalcogenide, observation and mass-tuning of Dirac-cone interface states, and discovery of Weyl and nodal-line semimetals.

  9. Spin-texture mapping in k-space by spin-resolved AREPS Competitive

    Souma Seigo, TAKAYAMA Akari

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (B)

    Institution: Tohoku University

    2014 - 2017

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    Spin-orbit coupling (SOC) in matter strongly affects an electron’s spin which points to various directions depending on the type of SOC interaction and crystal symmetry. In this study, we have developed our spin-resolved photoemission spectrometer and, by using this, studied the electronic structure of high functional materials in which a relation between spin and momentum plays an important role in this functionality. Consequently, we have observed various intriguing electronic states; Surface Fermi arc in Weyl semimetals, As 4p hole-band in dilute magnetic semiconductor GaMnAs, one dimensional edge state in heavy metal film, unexpected surface state in line node semimetals, and so on. Based on the above results, we conclude that this project has succeeded in establishing of new topological materials and unraveling of mechanism of ferromagnetism in GaMnAs.

  10. Electronic states of novel functional materials studied by ultrahigh-resolution three-dimensional spin- and angle-resolved photoemission spectroscopy

    TAKAHASHI Takashi, SATO Takafumi, SOUMA Seigo

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (S)

    Institution: Tohoku University

    2011/04/01 - 2015/03/31

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    We have constructed an ultrahigh-resolution three-dimensional spin- and angle-resolved photoemission spectrometer to elucidate the electronic states of novel functional materials such as spintronics-related materials. By developing a three-dimensional spin detector based on the very-low-energy-electron-diffraction method, we have obtained spin-resolved photoemission intensity two-orders-of-magnitude higher than that of the previous spin-resolved system. We have also achieved the energy resolution of 5 meV in the spin-resolved ARPES measurement, which is the world best at present. By using this spin-resolved system as well as synchrotron radiation, we have performed ARPES measurements on novel functional materials such as topological insulators, Rashba metals, and iron-based superconductors. We have succeeded in directly determining the fine electronic states in the vicinity of Fermi level responsible for the anomalous physical properties and novel quantum phenomena.

  11. 超高分解能３次元スピン分解光電子分光による新機能物質の基盤電子状態解析 Competitive

    高橋隆

    Offer Organization: 日本学術振興会

    System: 科学研究費補助金 基盤研究(S)

    Category: 基盤研究(A)

    Institution: 東北大学

    2011 - 2014

  12. Fabrication and electronic-structure analysis of topological nano-ribbon Competitive

    SOUMA Seigo

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Challenging Exploratory Research

    Institution: Tohoku University

    2012 - 2013

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    Despite of a huge effort for searching new topological materials carrying spin-helical Dirac fermions, mostly discovered are 3D materials by observing the surface state of topological insulator with angle-resolved photoemission spectroscopy. While the 2D topological system was theoretically proposed for several thin-film systems, a realization of such materials has been limited to very few systems mainly due to the difficulty in observing 1D edge state. In this research project, we have performed high-resolution spin-resolved ARPES on several topological insulators and thin film systems in order to elucidate the expected 1D-edge state which would emerge on nano-ribbon structure with a non-trivial topological nature. We have successfully determined bulk and surface/edge electronic structure in several topological insulators and related materials.

  13. Development of high-resolution photoemission spectroscopy for small-size superconductor Competitive

    SOUMA Seigo

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Young Scientists (A)

    Institution: Tohoku University

    2008 - 2010

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    To investigate the electronic structure of superconductors which has experimental difficulty such as tiny size of crystal and/or absence cleavage plane, we have developed experimental techniques and apparatus for high-resolution angle resolved photoemission spectroscopy on a small-size sample. As a result, we have succeeded in directly observing the basal electronic structure and/or superconducting gap for recently discovered exotic compounds such as Fe-pnictide superconductors and cement C12A7 electride.

  14. 高分解能角度分解光電子分光法による「多バンド」超伝導体の微細電子構造研究 Competitive

    相馬清吾

    Offer Organization: 日本学術振興会

    System: 科学研究費補助金 若手スタートアップ

    Category: 若手研究(スタートアップ)

    Institution: 東北大学

    2006 - 2007

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    前年度に引き続き、多バンド超伝導の可能性が指摘されているA15化合物V_3Siについて、超高分解能光電子分光による超伝導ギャップの研究を行った。ヘリウム光源による高分解能実験では、超伝導状態のスペクトルに10%程度metallic portionが混入し、ギャップの微細構造の議論を困難にするという問題があった。この問題を克服するため、バルク敏感光電子分光を可能にするキセノンプラズマ発光を用いた新たな高輝度・高分解能光源を開発した(発表論文1)。この新たな光源を、現行の高分解能光電子分高装置に組み込み、V_3Si単結晶の破断表面について高分解能光電子分光実験(△E=1.3meV)を行った結果、ヘリウム光源で観測されていたmetallic portionが大きく抑制される事を見出した(論文執筆中)。超伝導状態におけるスペクトル形状はBCS関数でほぼ再現されるが、フェルミ準位ごく近傍にBCS関数からの僅かなズレが認められており、超伝導ギャップに僅かな波数依存性がある可能性を示している。この点について解答を得るため、電子衝撃加熱とイオンスパッタリングにより作成した単結晶について、角度分解光電子分光による超伝導ギャップ波数依存性の決定を試みたが、試料上の温度が下がらず、明確な観測には至っていない。これは、試料の高温加熱と低温測定という二つの相反する要求から来る困難であり、今後解決していかなければならない問題である。A15化合物のようにへき開性の困難な物質の角度分解光電子分光を行うには、超高真空下で作成した単結晶についてinsitu測定を実行する必要があるが、その一環としてSi単結晶表面上に一次元金属単結晶薄膜を作成し、金属絶縁体転移の詳細な観測に成功した(発表論文4)。今後これを更に発展させた超伝導薄膜の実験を目論んでいる。また、近年注目されている空間反転対称性の破れた物質La2C3における超伝導ギャップの実験を行い、バンドのスピン軌道分裂に起因した多バンド超伝導の可能性を指摘した(発表論文5)。

  15. Development of ultrahigh-resolution photoemission spectrometer and study of quasiparticles in high-temperature superconductors

    TAKAHASHI Takashi, SATO Takafumi

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research

    Category: Grant-in-Aid for Scientific Research (S)

    Institution: Tohoku University

    2002 - 2005

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    In order to clarify the origin of quasiparticles in high-temperature superconductors, we have constructed a new ultrahigh-resolution angle-resolved photoemission (ARPES) spectrometer at Tohoku University. The spectrometer consists of (1) electron-energy analyzer, (2) light source, (3) analysis chamber, and (4) sample preparation chamber. As for the analyzer, we have improved the electric stability of the hemispherical part and the electron lens system, and also performed accurate sensitivity calibration of the CCD camera and the two-dimensional photoelectron detector. As for the light source, we have constructed a double differential pumping system as well as a VUV-filter which can pass ultraviolet-ray from the He discharge lamp but completely blocks residual gasses from the lamp. As for the sample chamber, we have developed a variable-angle manipulator which can rotate the angle with respect to the analyzer at low temperature. To effectively perform the ARPES experiment, we have developed a sample transfer system around the sample preparation chamber. To improve the vacuum during the measurement and to achieve low temperature, we have constructed multi-wall radiation shields with He-cycling cryostat. By making these efforts, we have finally achieved high performances as follows : (1) energy resolution : 1.3meV, (2) momentum resolution : 0.005Å^<-1>, (3) lowest temperature : 3.7K, and (4) vacuum during measurements : 2x10^<-11>Torr. By using this ultrahigh-resolution spectrometer, we have performed high-resolution ARPES measurements on following subjects. 1)Observation of Fermi surface, superconducting gap, and pseudogap in Bi-based high-temperature superconductors. 2)Direct observation of Bogoliubov quasiparticles on a triple-layered superconductor Bi2223. 3)Elucidation of the origin of kink in the dispersion in hole-doped high-temperature superconductors. 4)Direct observation of multiple-superconducting gaps in MgB_2. 5)Observation of magnetic isotope effect in energy dispersion of Bi-based high-temperature superconductors. 6)Direct observation of nonmonotonic d_x2_<-y2> wave superconducting gap in electron-doped high-temperature superconductors.

  16. 高温超伝導および高温強磁性ホウ素化合物の高分解能角度分解光電子分光

    相馬 清吾

    Offer Organization: 日本学術振興会

    System: 科学研究費助成事業

    Category: 特別研究員奨励費

    Institution: 東北大学

    2002 - 2004

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    前年度に引き続き、「超高分解能光電子分光装置」の更なる改良を行った。光電子検出系において、高画素数のCCDカメラを導入し、これに伴い電子レンズシステムの再調整を行った。また、データ転送システムと測定プログラムを改良する事で、測定時間を大幅に短縮した。さらに、試料を取り囲む熱輻射シールドの全表面に金メッキを施すことで、固体試料において最高エネルギー分解能1.3meVを達成した。これらの装置改良と並行して、高分解能角度分解光電子分光法により、ホウ素化合物の電子構造に以下の新しい知見を得た。本研究での高分解能角度分解光電子分光実験により、そのMgB_2の超伝導機構が基本的に2バンド超伝導の枠組みで理解できることを示したが、その際、Γ(A)点で観測された電子面が、LDAバンド計算では全く再現されず、大きく食い違っているという問題点が残った。そこで、MgB_2の非超伝導参照物質で全く同一の結晶構造を持つAlB_2の高分解能角度分解光電子分光実験を行い、この物質のバンド構造とフェルミ面を決定した。MgB_2の結果と比較すると、両物質でπバンドはK(H)点近くでフェルミ準位を切るのに対し、σバンドはAlB_2では完全に占有されている事を見いだした。また、AlB_2においてもΓ(A)点中心の電子面を観測し、LDAバンド計算と大きく食い違っている事を見出した。この食い違いの起源として表面特有の電子構造の影響を検討する目的で、光電子の脱出長が紫外光の3倍以上であるX線を用いて角度分解光電子分光実験を行った。その結果、このバンドは表面に由来する構造である事を見いだした。以上の事から、LDA計算を基礎として構築された2バンドモデルは妥当であり、MgB_2の超伝導にはσバンドが重要な寄与を持っていると結論した。

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Teaching Experience 3

  1. Basic Spintronics and Material Science I　Tohoku University

  2. 物理学実験3　東北大学

  3. 物理学基礎研究　東北大学