Details of the Researcher

PHOTO

Yusuke Kozuka
Section
Advanced Institute for Materials Research
Job title
Professor
Degree

  • 博士（科学）（東京大学）

  • 修士（科学）（東京大学）

e-Rad No.
70580372
Researcher ID
E-6470-2010

Research History 13

  • 2025/05 - Present
    Tohoku University　Advanced Institute for Materials Research　Professor

  • 2024/09 - Present
    Waseda University　Faculty of Science and Engineering　Professor

  • 2023/04 - Present
    National Institute for Materials Science　Research Center for Materials Nanoarchitectonics　Group Leader

  • 2024/04 - 2024/09
    Waseda University　Faculty of Science and Engineering　Guest Professor

  • 2022/04 - 2023/03
    National Institute for Materials Science　Research Center for Magnetic and Spintronic Materials　Principal Researcher

  • 2021/04 - 2022/03
    National Institute for Materials Science　Research Center for Magnetic and Spintronic Materials　Senior Researcher

  • 2017/10 - 2021/03
    PRESTO researcher

  • 2018/04 - 2019/03
    National Institute for Materials Science　Research Center for Magnetic and Spintronic Materials　Independent Scientist

  • 2016/10 - 2018/03
    The University of Tokyo　School of Engineering　Lecturer

  • 2013/08 - 2016/09
    The University of Tokyo　School of Engineering　Project Lecturer

  • 2011/04 - 2013/07
    The University of Tokyo　School of Engineering　Research Associate

  • 2010/04 - 2011/03
    Tohoku University　Institute for Materials Research　Assistant Professor

  • 2007/04 - 2010/03
    Japan Society for the Promotion of Science　Research Fellow

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Education 2

  • The University of Tokyo　Graduate School of Frontier Sciences　Department of Advanced Materials Science

    2005/04 - 2010/03

  • The University of Tokyo　Faculty of Engineering　Department of Applied Physics

    2001/04 - 2005/03

Professional Memberships 3

  • Materials Research Society

  • THE PHYSICAL SOCIETY OF JAPAN

  • THE JAPAN SOCIETY OF APPLIED PHYSICS

Research Interests 3

  • Oxide thin film

  • Superconducting thin film

  • Quantum Hall effect

Research Areas 3

  • Nanotechnology/Materials / Thin-film surfaces and interfaces /

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

  • Natural sciences / Semiconductors, optical and atomic physics /

Awards 4

  1. Commendation for Science and Technology by MEXT, The Young Scientists' Prize

    2018/04　MEXT

  2. 27th Inoue Research Award for Young Scientists

    2011/02　Inoue Foundation for Science

  3. 24th Advanced Technology Award, Nippon broadcasting system, inc. prize

    2010/07　FujiSankei Business i

  4. 27th JSAP Young Scientist Award for the Presentation of an Excellent Paper

    2010/03　The Japan Society of Applied Physics　Shubnikov-de Haas Oscillations in Strontium Titanate Ultrathin Films

Papers 121

  1. Theory for tunnel magnetoresistance oscillation

    Keisuke Masuda, Thomas Scheike, Hiroaki Sukegawa, Yusuke Kozuka, Seiji Mitani, Yoshio Miura

    Physical Review B　2025/06/09

    DOI： 10.1103/PhysRevB.111.L220406 　

  2. Structural, optical, and electronic properties of Mg Zn1-O (0 ≤ x ≤ 0.38) films pseudomorphically grown on Zn-polar ZnO substrates

    Yusuke Kozuka, Shunsuke Tsuda, Thang Dinh Phan, Koichiro Yaji, Jun Uzuhashi, Tadakatsu Ohkubo, Takanobu Hiroto, Takayuki Makino, Joseph Falson, Atsushi Tsukazaki, Masashi Kawasaki

    Materials Today Quantum　2025/06

    DOI： 10.1016/j.mtquan.2025.100036 　

  3. Enhancement of Transverse Thermoelectric Conversion by Interface‐Induced Spin Current in Ferromagnetic Metal/Nonmagnetic Insulator Hybrid‐Structure

    Takuma Itoh, Yusuke Kozuka, Takamasa Hirai, Ken‐ichi Uchida

    Advanced Functional Materials　2024/12

    DOI： 10.1002/adfm.202409557 　

  4. Parity-independent Kondo effect of correlated electrons in electrostatically defined ZnO quantum dots

    Kosuke Noro, Yusuke Kozuka, Kazuma Matsumura, Takeshi Kumasaka, Yoshihiro Fujiwara, Atsushi Tsukazaki, Masashi Kawasaki, Tomohiro Otsuka

    Nature Communications　2024/11/07

    DOI： 10.1038/s41467-024-53890-2 　

  5. Robust Preparation of Sub‐20‐nm‐Thin Lamellae for Aberration‐Corrected Electron Microscopy

    Hideyo Tsurusawa, Jun Uzuhashi, Yusuke Kozuka, Koji Kimoto, Tadakatsu Ohkubo

    Small Methods　2024/09

    DOI： 10.1002/smtd.202301425 　

  6. Microscopic evaluation of spin and orbital moment in ferromagnetic resonance

    Yuta Ishii, Yuichi Yamasaki, Yusuke Kozuka, Jana Lustikova, Yoichi Nii, Yoshinori Onose, Yuichi Yokoyama, Masaichiro Mizumaki, Jun-ichi Adachi, Hironori Nakao, Taka-hisa Arima, Yusuke Wakabayashi

    Scientific Reports　14　(1)　2024/07/05

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1038/s41598-024-66139-1 　

    eISSN： 2045-2322

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    Abstract Time-resolved X-ray magnetic circular dichroism under the effects of ferromagnetic resonance (FMR), known as X-ray ferromagnetic resonance (XFMR) measurements, enables direct detection of precession dynamics of magnetic moment. Here we demonstrated XFMR measurements and Bayesian analyses as a quantitative probe for the precession of spin and orbital magnetic moments under the FMR effect. Magnetization precessions in two different Pt/Ni-Fe thin film samples were directly detected. Furthermore, the ratio of dynamical spin and orbital magnetic moments was evaluated quantitatively by Bayesian analyses for XFMR energy spectra around the Ni $$L_{2,3}$$ absorption edges. Our study paves the way for a microscopic investigation of the contribution of the orbital magnetic moment to magnetization dynamics.

  7. Large anomalous Hall effect in spin fluctuating devil’s staircase

    Naoki Abe, Yuya Hano, Hiroaki Ishizuka, Yusuke Kozuka, Terumasa Tadano, Yoshihiro Tsujimoto, Kazunari Yamaura, Shintaro Ishiwata, Jun Fujioka

    npj Quantum Materials　2024/05/17

    DOI： 10.1038/s41535-024-00653-3 　

  8. Epitaxy and transport properties of alkali-earth palladate thin films

    Yusuke Kozuka, Taisuke T. Sasaki, Terumasa Tadano, Jun Fujioka

    Science and Technology of Advanced Materials　2023/12/31

    DOI： 10.1080/14686996.2023.2265431 　

  9. Charge transport and thermopower in the electron-doped narrow gap semiconductor Ca1−xLaxPd3O4

    Kouta Kazama, Masato Sakano, Kohei Yamagami, Takuo Ohkochi, Kyoko Ishizaka, Terumasa Tadano, Yusuke Kozuka, Hidetoshi Yoshizawa, Yoshihiro Tsujimoto, Kazunari Yamaura, Jun Fujioka

    Physical Review Materials　2023/08/11

    DOI： 10.1103/PhysRevMaterials.7.085402 　

  10. Observation of charge-to-spin conversion with giant efficiency at Ni0.8Fe0.2/Bi2WO6 interface

    Saikat Das, Satoshi Sugimoto, Varun Kumar Kushwaha, Yusuke Kozuka, Shinya Kasai

    APL Materials　2023/04/01

    DOI： 10.1063/5.0142695 　

  11. Observation of charge-to-spin conversion with giant efficiency at Ni0.8Fe0.2/Bi2WO6interface

    Das, S., Sugimoto, S., Kushwaha, V.K., Kozuka, Y., Kasai, S.

    APL Materials　11　(4)　2023

    DOI： 10.1063/5.0142695 　

    ISSN： 2166-532X

  12. Wide modulation of coercive fields in Mn<inf>4</inf>N ferrimagnetic thin films caused dominantly by dislocation microstructures

    Shinji Isogami, Mitsuru Ohtake, Yusuke Kozuka, Yukiko K. Takahashi

    Journal of Magnetism and Magnetic Materials　560　2022/10/15

    DOI： 10.1016/j.jmmm.2022.169642 　

    ISSN： 0304-8853

  13. Ensemble spin relaxation of shallow donor qubits in ZnO

    Vasileios Niaouris, Mikhail Durnev, Xiayu Linpeng, Maria L. K. Viitaniemi, Christian Zimmermann, Aswin Vishnuradhan, Yusuke Kozuka, Masashi Kawasaki, Kai-Mei C. Fu

    PHYSICAL REVIEW B　105　(19)　2022/05

    DOI： 10.1103/PhysRevB.105.195202 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  14. Competing correlated states around the zero-field Wigner crystallization transition of electrons in two dimensions

    J. Falson, I. Sodemann, B. Skinner, D. Tabrea, Y. Kozuka, A. Tsukazaki, M. Kawasaki, K. von Klitzing, J. H. Smet

    Nature Materials　21　(3)　311-316　2022/03

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1038/s41563-021-01166-1 　

    ISSN： 1476-1122

    eISSN： 1476-4660

  15. Interplay of spin–orbit coupling and Coulomb interaction in ZnO-based electron system

    D. Maryenko, M. Kawamura, A. Ernst, V. K. Dugaev, E. Ya. Sherman, M. Kriener, M. S. Bahramy, Y. Kozuka, M. Kawasaki

    Nature Communications　12　(1)　2021/12

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1038/s41467-021-23483-4 　

    eISSN： 2041-1723

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    <title>Abstract</title>Spin–orbit coupling (SOC) is pivotal for various fundamental spin-dependent phenomena in solids and their technological applications. In semiconductors, these phenomena have been so far studied in relatively weak electron–electron interaction regimes, where the single electron picture holds. However, SOC can profoundly compete against Coulomb interaction, which could lead to the emergence of unconventional electronic phases. Since SOC depends on the electric field in the crystal including contributions of itinerant electrons, electron–electron interactions can modify this coupling. Here we demonstrate the emergence of the SOC effect in a high-mobility two-dimensional electron system in a simple band structure MgZnO/ZnO semiconductor. This electron system also features strong electron–electron interaction effects. By changing the carrier density with Mg-content, we tune the SOC strength and achieve its interplay with electron–electron interaction. These systems pave a way to emergent spintronic phenomena in strong electron correlation regimes and to the formation of quasiparticles with the electron spin strongly coupled to the density.

  16. Efficient current-driven magnetization switching owing to isotropic magnetism in a highly symmetric 111-oriented Mn<inf>4</inf>N epitaxial single layer

    Shinji Isogami, Nagalingam Rajamanickam, Yusuke Kozuka, Yukiko K. Takahashi

    AIP Advances　11　(10)　2021/10/01

    DOI： 10.1063/5.0062253 　

    eISSN： 2158-3226

  17. Observation of Nonlinear Spin-Charge Conversion in the Thin Film of Nominally Centrosymmetric Dirac Semimetal SrIrO3 at Room Temperature

    Y. Kozuka, S. Isogami, K. Masuda, Y. Miura, Saikat Das, J. Fujioka, T. Ohkubo, S. Kasai

    Physical Review Letters　126　(23)　2021/06/09

    Publisher: American Physical Society (APS)

    DOI： 10.1103/physrevlett.126.236801 　

    ISSN： 0031-9007

    eISSN： 1079-7114

  18. Negative correlation between the linear and the nonlinear conductance in magnetic tunnel junctions

    Shuichi Iwakiri, Satoshi Sugimoto, Yasuhiro Niimi, Yusuke Kozuka, Yukiko K. Takahashi, Shinya Kasai, Kensuke Kobayashi

    PHYSICAL REVIEW B　103　(24)　2021/06

    DOI： 10.1103/PhysRevB.103.245427 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  19. Deterministic Influence of Substrate-Induced Oxygen Vacancy Diffusion on Bi2WO6Thin Film Growth

    Das, S., Ohkubo, T., Kasai, S., Kozuka, Y.

    Crystal Growth and Design　21　(1)　2021

    DOI： 10.1021/acs.cgd.0c01428 　

    ISSN： 1528-7505 1528-7483

  20. Microwave response of interacting oxide two-dimensional electron systems International-journal International-coauthorship Peer-reviewed

    Tabrea, D., Dmitriev, I.A., Dorozhkin, S.I., Gorshunov, B.P., Boris, A.V., Kozuka, Y., Tsukazaki, A., Kawasaki, M., Von Klitzing, K., Falson, J.

    Physical Review B　102　(11)　115432-1-115432-8　2020/09/24

    Publisher: American Physical Society

    DOI： 10.1103/PhysRevB.102.115432 　

    ISSN： 2469-9969 2469-9950

  21. Current scaling of the topological quantum phase transition between a quantum anomalous Hall insulator and a trivial insulator Peer-reviewed

    Minoru Kawamura, Masataka Mogi, Ryutaro Yoshimi, Atsushi Tsukazaki, Yusuke Kozuka, Kei S. Takahashi, Masashi Kawasaki, Yoshinori Tokura

    Physical Review B　102　(4)　2020/07/16

    DOI： 10.1103/physrevb.102.041301 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  22. Generation of multipeak spectrum of spin torque oscillator in non-linear regime Peer-reviewed

    Shuichi Iwakiri, Satoshi Sugimoto, Yasuhiro Niimi, Kensuke Kobayashi, Yusuke Kozuka, Yukiko K. Takahashi, Shinya Kasai

    Applied Physics Letters　117　(2)　022406-022406　2020/07/13

    Publisher: AIP Publishing

    DOI： 10.1063/5.0013102 　

    ISSN： 0003-6951

    eISSN： 1077-3118

  23. Multiple modes of a single spin torque oscillator under the non-linear region

    Satoshi Sugimoto, Shuichi Iwakiri, Yusuke Kozuka, Yukiko Takahashi, Yasuhiro Niimi, Kensuke Kobayashi, Shinya Kasai

    AIP ADVANCES　10　(7)　2020/07

    DOI： 10.1063/5.0013105 　

    eISSN： 2158-3226

  24. Ballistic transport in periodically modulated MgZnO/ZnO two-dimensional electron systems Peer-reviewed

    Tanaka, K., Falson, J., Kozuka, Y., Uchida, M., Maryenko, D., Ye, J.T., Iwasa, Y., Tsukazaki, A., Smet, J.H., Kawasaki, M.

    Applied Physics Letters　115　(15)　153101-1-153101-4　2019/10

    DOI： 10.1063/1.5121005 　

    ISSN： 0003-6951

  25. Anomalous enhancement of upper critical field in Sr2RuO4 thin films Peer-reviewed

    Masaki Uchida, Motoharu Ide, Minoru Kawamura, Kei S. Takahashi, Yusuke Kozuka, Yoshinori Tokura, Masashi Kawasaki

    Physical Review B　99　(16)　2019/04/16

    DOI： 10.1103/physrevb.99.161111 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  26. Quantized conductance of one-dimensional strongly correlated electrons in an oxide heterostructure Peer-reviewed

    Hou, H., Kozuka, Y., Liao, J.-W., Smith, L.W., Kos, D., Griffiths, J.P., Falson, J., Tsukazaki, A., Kawasaki, M., Ford, C.J.B.

    Physical Review B　99　(12)　121302-1-121302-6　2019/03

    DOI： 10.1103/PhysRevB.99.121302 　

    ISSN： 2469-9969 2469-9950

  27. Erratum: Topological spin-hedgehog crystals of a chiral magnet as engineered with magnetic anisotropy (Physical Review B (2017) (96) (220414) DOI: 10.1103/PhysRevB.96.220414)

    Kanazawa, N., White, J.S., R?nnow, H.M., Dewhurst, C.D., Morikawa, D., Shibata, K., Arima, T., Kagawa, F., Tsukazaki, A., Kozuka, Y., Ichikawa, M., Kawasaki, M., Tokura, Y.

    Physical Review B　99　(8)　2019

    DOI： 10.1103/PhysRevB.99.089902 　

    ISSN： 2469-9969 2469-9950

  28. Andreev Reflection at the Interface with an Oxide in the Quantum Hall Regime Peer-reviewed

    Kozuka Yusuke, Sakaguchi Atsushi, Falson Joseph, Tsukazaki Atsushi, Kawasaki Masashi

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN　87　(12)　2018/12/15

    DOI： 10.7566/JPSJ.87.124712 　

    ISSN： 0031-9015

  29. Composite fermion liquid to Wigner solid transition in the lowest Landau level of zinc oxide

    D. Maryenko, A. McCollam, J. Falson, Y. Kozuka, J. Bruin, U. Zeitler, M. Kawasaki

    Nature Communications　9　(1)　2018/12

    Publisher: Springer Science and Business Media LLC

    DOI： 10.1038/s41467-018-06834-6 　

    eISSN： 2041-1723

  30. Electric-field control of anomalous and topological Hall effects in oxide bilayer thin films Peer-reviewed

    Yuki Ohuchi, Jobu Matsuno, Naoki Ogawa, Yusuke Kozuka, Masaki Uchida, Yoshinori Tokura, Masashi Kawasaki

    Nature Communications　9　(1)　2018/12/01

    DOI： 10.1038/s41467-017-02629-3 　

    ISSN： 2041-1723

  31. Structural characterisation of high-mobility Cd3As2 films crystallised on SrTiO3 Peer-reviewed

    Yusuke Nakazawa, Masaki Uchida, Shinichi Nishihaya, Markus Kriener, Yusuke Kozuka, Yasujiro Taguchi, Masashi Kawasaki

    Scientific Reports　8　(1)　2018/12/01

    DOI： 10.1038/s41598-018-20758-7 　

    ISSN： 2045-2322

  32. Topological quantum phase transition in magnetic topological insulator upon magnetization rotation Peer-reviewed

    Minoru Kawamura, Masataka Mogi, Ryutaro Yoshimi, Atsushi Tsukazaki, Yusuke Kozuka, Kei S. Takahashi, Masashi Kawasaki, Yoshinori Tokura

    Physical Review B　98　(14)　2018/10/22

    DOI： 10.1103/physrevb.98.140404 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  33. Ferroelectric field control of charge density in oxide films with polarization reversal by electric double layer Peer-reviewed

    Nishino Ryutaro, Kozuka Yusuke, Kagawa Fumitaka, Uchida Masaki, Kawasaki Masashi

    APPLIED PHYSICS LETTERS　113　(14)　2018/10/01

    DOI： 10.1063/1.5047558 　

    ISSN： 0003-6951

    eISSN： 1077-3118

  34. A cascade of phase transitions in an orbitally mixed half-filled Landau level Peer-reviewed

    Falson, J., Tabrea, D., Zhang, D., Sodemann, I., Kozuka, Y., Tsukazaki, A., Kawasaki, M., Von Klitzing, K., Smet, J.H.

    Science Advances　4　(9)　2018/09

    DOI： 10.1126/sciadv.aat8742 　

    ISSN： 2375-2548

  35. Negative magnetoresistance suppressed through a topological phase transition in (Cd1-xZnx)3As2 thin films

    Nishihaya, S., Uchida, M., Nakazawa, Y., Akiba, K., Kriener, M., Kozuka, Y., Miyake, A., Taguchi, Y., Tokunaga, M., Kawasaki, M.

    Physical Review B　97　(24)　2018/06

    DOI： 10.1103/PhysRevB.97.245103 　

    ISSN： 2469-9969 2469-9950

  36. Gate-tuned quantum Hall states in Dirac semimetal (Cd1-xZnx)3As2 Peer-reviewed

    Shinichi Nishihaya, Masaki Uchida, Yusuke Nakazawa, Markus Kriener, Yusuke Kozuka, Yasujiro Taguchi, Masashi Kawasaki

    Science Advances　4　(5)　2018/05/18

    DOI： 10.1126/sciadv.aar5668 　

    ISSN： 2375-2548

  37. Electrical conduction on the surface of ferroelectric PbTiO3 thin film induced by electrolyte gating Peer-reviewed

    Ryutaro Nishino, Yusuke Kozuka, Masaki Uchida, Fumitaka Kagawa, Masashi Kawasaki

    Applied Physics Letters　112　(5)　2018/01/29

    DOI： 10.1063/1.5010391 　

    ISSN： 0003-6951

    eISSN： 1077-3118

  38. All-in-all-out magnetic domain inversion in Tb2Ir2O7 with molecular fields antiparallel to external fields Peer-reviewed

    Fujita T. C, Kozuka Y, Matsuno J, Uchida M, Tsukazaki A, Arima T, Kawasaki M

    PHYSICAL REVIEW MATERIALS　2　(1)　2018/01/25

    DOI： 10.1103/PhysRevMaterials.2.011402 　

    ISSN： 2475-9953

    eISSN： 2475-9953

  39. Coherence Properties of Shallow Donor Qubits in Zn O

    Linpeng, X., Viitaniemi, M.L.K., Vishnuradhan, A., Kozuka, Y., Johnson, C., Kawasaki, M., Fu, K.-M.C.

    Physical Review Applied　10　(6)　2018

    DOI： 10.1103/PhysRevApplied.10.064061 　

    ISSN： 2331-7019

  40. Visualizing ferroic domains in an all-in-all-out antiferromagnet thin film Peer-reviewed

    Y. Kozuka, T. C. Fujita, M. Uchida, T. Nojima, A. Tsukazaki, J. Matsuno, T. Arima, M. Kawasaki

    PHYSICAL REVIEW B　96　(22)　2017/12

    DOI： 10.1103/PhysRevB.96.224417 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  41. Quantum Hall states observed in thin films of Dirac semimetal Cd3As2 Peer-reviewed

    Masaki Uchida, Yusuke Nakazawa, Shinichi Nishihaya, Kazuto Akiba, Markus Kriener, Yusuke Kozuka, Atsushi Miyake, Yasujiro Taguchi, Masashi Tokunaga, Naoto Nagaosa, Yoshinori Tokura, Masashi Kawasaki

    NATURE COMMUNICATIONS　8　2017/12

    DOI： 10.1038/s41467-017-02423-1 　

    ISSN： 2041-1723

  42. Nonlinear response of a MgZnO/ZnO heterostructure close to zero bias Peer-reviewed

    Shi, Q., Falson, J., Zudov, M.A., Kozuka, Y., Tsukazaki, A., Kawasaki, M., Smet, J.

    Physical Review B　96　(12)　125401-1-125401-4　2017/09/05

    DOI： 10.1103/PhysRevB.96.125401 　

    ISSN： 2469-9969 2469-9950

  43. Observation of anomalous Hall effect in a non-magnetic two-dimensional electron system Peer-reviewed

    Maryenko, D., Mishchenko, A.S., Bahramy, M.S., Ernst, A., Falson, J., Kozuka, Y., Tsukazaki, A., Nagaosa, N., Kawasaki, M.

    Nature Communications　8　14777-1-14777-7　2017/03/16

    DOI： 10.1038/ncomms14777 　

    ISSN： 2041-1723

  44. A magnetic heterostructure of topological insulators as a candidate for an axion insulator Peer-reviewed

    Mogi, M., Kawamura, M., Yoshimi, R., Tsukazaki, A., Kozuka, Y., Shirakawa, N., Takahashi, K.S., Kawasaki, M., Tokura, Y.

    Nature Materials　16　(5)　516-521　2017/02/13

    DOI： 10.1038/nmat4855 　

    ISSN： 1476-4660 1476-1122

  45. Hall field-induced resistance oscillations in MgZnO/ZnO heterostructures Peer-reviewed

    Shi, Q., Zudov, M.A., Falson, J., Kozuka, Y., Tsukazaki, A., Kawasaki, M., Von Klitzing, K., Smet, J.

    Physical Review B　95　(4)　1411-1411　2017/01/30

    DOI： 10.1103/PhysRevB.95.041411 　

    ISSN： 2469-9969 2469-9950

  46. Alloy disorder modulated electron transport at MgxZn1-xO/ZnO heterointerface Peer-reviewed

    Aswin Vishnuradhan, Y. Kozuka, M. Uchida, J. Falson, A. Tsukazaki, M. Kawasaki

    AIP ADVANCES　7　(1)　2017/01

    DOI： 10.1063/1.4974462 　

    ISSN： 2158-3226

  47. Topological spin-hedgehog crystals of a chiral magnet as engineered with magnetic anisotropy Peer-reviewed

    Kanazawa, N., White, J.S., R?nnow, H.M., Dewhurst, C.D., Morikawa, D., Shibata, K., Arima, T., Kagawa, F., Tsukazaki, A., Kozuka, Y., Ichikawa, M., Kawasaki, M., Tokura, Y.

    Physical Review B　96　(22)　220414　2017

    DOI： 10.1103/PhysRevB.96.220414 　

    ISSN： 2469-9969 2469-9950

  48. Direct observation of anisotropic magnetic field response of the spin helix in FeGe thin films Peer-reviewed

    Kanazawa, N., White, J.S., R?nnow, H.M., Dewhurst, C.D., Fujishiro, Y., Tsukazaki, A., Kozuka, Y., Kawasaki, M., Ichikawa, M., Kagawa, F., Tokura, Y.

    Physical Review B　94　(18)　184432　2016/11/28

    DOI： 10.1103/PhysRevB.94.184432 　

    ISSN： 2469-9969 2469-9950

  49. Evolution of Insulator-Metal Phase Transitions in Epitaxial Tungsten Oxide Films during Electrolyte-Gating Peer-reviewed

    Shinichi Nishihaya, Masaki Uchida, Yusuke Kozuka, Yoshihiro Iwasa, Masashi Kawasaki

    ACS APPLIED MATERIALS & INTERFACES　8　(34)　22330-22336　2016/08

    DOI： 10.1021/acsami.6b06593 　

    ISSN： 1944-8244

    eISSN： 1944-8252

  50. Observation of the quantum Hall effect in δ-doped SrTiO3 Peer-reviewed

    Matsubara, Y., Takahashi, K.S., Bahramy, M.S., Kozuka, Y., Maryenko, D., Falson, J., Tsukazaki, A., Tokura, Y., Kawasaki, M.

    Nature Communications　7　11631-11631　2016/05/27

    DOI： 10.1038/ncomms11631 　

    ISSN： 2041-1723

  51. MgZnO/ZnO heterostructures with electron mobility exceeding 1 x 10(6) cm(2)/Vs Peer-reviewed

    Joseph Falson, Yusuke Kozuka, Masaki Uchida, Jurgen H. Smet, Taka-hisa Arima, Atsushi Tsukazaki, Masashi Kawasaki

    SCIENTIFIC REPORTS　6　2016/05

    DOI： 10.1038/srep26598 　

    ISSN： 2045-2322

  52. All-in-all-out magnetic domain wall conduction in a pyrochlore iridate heterointerface Peer-reviewed

    T. C. Fujita, M. Uchida, Y. Kozuka, W. Sano, A. Tsukazaki, T. Arima, M. Kawasaki

    PHYSICAL REVIEW B　93　(6)　2016/02

    DOI： 10.1103/PhysRevB.93.064419 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  53. Epitaxially Stabilized Oxide Composed of Twisted Triangular-Lattice Layers Peer-reviewed

    Masaki Uchida, Kenta Ohba, Yuki Ohuchi, Yusuke Kozuka, Masashi Kawasaki

    CHEMISTRY OF MATERIALS　28　(4)　1165-1169　2016/02

    DOI： 10.1021/acs.chemmater.5b04702 　

    ISSN： 0897-4756

    eISSN： 1520-5002

  54. Observation of microwave induced resistance and photovoltage oscillations in MgZnO/ZnO heterostructures Peer-reviewed

    D. F. Kärcher, A. V. Shchepetilnikov, Yu. A. Nefyodov, J. Falson, I. A. Dmitriev, Y. Kozuka, D. Maryenko, A. Tsukazaki, S. I. Dorozhkin, I. V. Kukushkin, M. Kawasaki, J. H. Smet

    Physical Review B　93　(4)　2016/01/15

    Publisher: American Physical Society

    DOI： 10.1103/PhysRevB.93.041410 　

    ISSN： 2469-9969 2469-9950

  55. 21pBN-16 パイロクロア型イリジウム酸化物ヘテロ界面における磁気ドメイン壁伝導

    藤田 貴啓, 打田 正輝, 小塚 裕介, 佐野 航, 小川 翔平, 塚崎 敦, 有馬 孝尚, 川崎 雅司

    日本物理学会講演概要集　71　2324-2324　2016

    Publisher: 一般社団法人日本物理学会

    DOI： 10.11316/jpsgaiyo.71.1.0_2324 　

    ISSN： 2189-079X

  56. 19aBM-6 Magnetic anisotropy effect on a helical magnetic structure confined in an FeGe thin film

    Kanazawa N., White Jonathan, Ronnow Henrik, Dewhurst Charles, Fujishiro Y., Tsukazaki A., Kozuka Y., Kawasaki M., Ichikawa M., Kagawa F., Tokura Y.

    Meeting Abstracts of the Physical Society of Japan　71　1971-1971　2016

    Publisher: The Physical Society of Japan (JPS)

    DOI： 10.11316/jpsgaiyo.71.1.0_1971 　

    ISSN： 2189-079X

  57. 22aBA-6 Higher-temperature quantum anomalous Hall effect in magnetic modulation-doped topological insulators

    Mogi M., Yoshimi R., Tsukazaki A., Yasuda K., Kozuka Y., Takahashi K. S., Kawasaki M., Tokura Y.

    Meeting Abstracts of the Physical Society of Japan　71　1415-1415　2016

    Publisher: The Physical Society of Japan (JPS)

    DOI： 10.11316/jpsgaiyo.71.1.0_1415 　

    ISSN： 2189-079X

  58. Towards the observation of domain-wall conduction in magnetic topological insulator Crx(Bi1-ySby)2-xTe3 thin films

    Yoshimi Ryutaro, Mogi Masataka, Tsukazaki Atsushi, Kozuka Yusuke, Takahashi Kei, Kawasaki Masashi, Tokura Yoshinori

    Meeting Abstracts of the Physical Society of Japan　71　1187-1187　2016

    Publisher: The Physical Society of Japan

    DOI： 10.11316/jpsgaiyo.71.2.0_1187 　

  59. 2DEG/superconductor junctions using MgxZn1-xO/ZnO heterostructures

    Kozuka Y., Sakaguchi A., Aswin V., Falson J., Maryenko D., Uchida M., Tsukazaki A., Kawasaki M.

    Meeting Abstracts of the Physical Society of Japan　71　1039-1039　2016

    Publisher: The Physical Society of Japan

    DOI： 10.11316/jpsgaiyo.71.2.0_1039 　

  60. All-in-all-out magnetic domain size in pyrochlore iridate thin films as probed by local magnetotransport Peer-reviewed

    T. C. Fujita, M. Uchida, Y. Kozuka, S. Ogawa, A. Tsukazaki, T. Arima, M. Kawasaki

    APPLIED PHYSICS LETTERS　108　(2)　2016/01

    DOI： 10.1063/1.4939742 　

    ISSN： 0003-6951

    eISSN： 1077-3118

  61. Effective carrier doping and metallization in LaxSr2-x-yBayIrO4-delta thin films Peer-reviewed

    M. Ito, M. Uchida, Y. Kozuka, K. S. Takahashi, M. Kawasaki

    PHYSICAL REVIEW B　93　(4)　2016/01

    DOI： 10.1103/PhysRevB.93.045139 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  62. Observation of microwave induced resistance and photovoltage oscillations in MgZnO/ZnO heterostructures Peer-reviewed

    D. F. Kaercher, A. V. Shchepetilnikov, Yu. A. Nefyodov, J. Falson, I. A. Dmitriev, Y. Kozuka, D. Maryenko, A. Tsukazaki, S. I. Dorozhkin, I. V. Kukushkin, M. Kawasaki, J. H. Smet

    PHYSICAL REVIEW B　93　(4)　2016/01

    DOI： 10.1103/PhysRevB.93.041410 　

    ISSN： 1098-0121

    eISSN： 1550-235X

  63. Thermal Generation of Spin Current in an Antiferromagnet Peer-reviewed

    S. Seki, T. Ideue, M. Kubota, Y. Kozuka, R. Takagi, M. Nakamura, Y. Kaneko, M. Kawasaki, Y. Tokura

    PHYSICAL REVIEW LETTERS　115　(26)　2015/12

    DOI： 10.1103/PhysRevLett.115.266601 　

    ISSN： 0031-9007

    eISSN： 1079-7114

  64. Magnetic modulation doping in topological insulators toward higher-temperature quantum anomalous Hall effect Peer-reviewed

    M. Mogi, R. Yoshimi, A. Tsukazaki, K. Yasuda, Y. Kozuka, K. S. Takahashi, M. Kawasaki, Y. Tokura

    APPLIED PHYSICS LETTERS　107　(18)　2015/11

    DOI： 10.1063/1.4935075 　

    ISSN： 0003-6951

    eISSN： 1077-3118

  65. Magnetic properties of spin frustrated spinel ZnFe2O4/ZnCr2O4 superlattices Peer-reviewed

    T. Murata, Y. Kozuka, M. Uchida, M. Kawasaki

    JOURNAL OF APPLIED PHYSICS　118　(19)　2015/11

    DOI： 10.1063/1.4935818 　

    ISSN： 0021-8979

    eISSN： 1089-7550

  66. Spin-Selective Electron Quantum Transport in Nonmagnetic MgZnO/ZnO Heterostructures Peer-reviewed

    D. Maryenko, J. Falson, M. S. Bahramy, I. A. Dmitriev, Y. Kozuka, A. Tsukazaki, M. Kawasaki

    PHYSICAL REVIEW LETTERS　115　(19)　2015/11

    DOI： 10.1103/PhysRevLett.115.197601 　

    ISSN： 0031-9007

    eISSN： 1079-7114

  67. Formation of In-plane Skyrmions in Epitaxial MnSi Thin Films as Revealed by Planar Hall Effect Peer-reviewed

    Tomoyuki Yokouchi, Naoya Kanazawa, Atsushi Tsukazaki, Yusuke Kozuka, Akiko Kikkawa, Yasujiro Taguchi, Masashi Kawasaki, Masakazu Ichikawa, Fumitaka Kagawa, Yoshinori Tokura

    JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN　84　(10)　1-104708　2015/10

    DOI： 10.7566/JPSJ.84.104708 　

    ISSN： 0031-9015

  68. Electron scattering times in ZnO based polar heterostructures Peer-reviewed

    J. Falson, Y. Kozuka, J. H. Smet, T. Arima, A. Tsukazaki, M. Kawasaki

    APPLIED PHYSICS LETTERS　107　(8)　2015/08

    DOI： 10.1063/1.4929381 　

    ISSN： 0003-6951

    eISSN： 1077-3118

  69. Band alignment and photovoltaic effect of epitaxial alpha-PbO thin films Peer-reviewed

    Eishi Majima, Yusuke Kozuka, Masaki Uchida, Masao Nakamura, Masashi Kawasaki

    APPLIED PHYSICS EXPRESS　8　(7)　2015/07

    DOI： 10.7567/APEX.8.074001 　

    ISSN： 1882-0778

    eISSN： 1882-0786

  70. Field-direction control of the type of charge carriers in nonsymmorphic IrO2 Peer-reviewed

    M. Uchida, W. Sano, K. S. Takahashi, T. Koretsune, Y. Kozuka, R. Arita, Y. Tokura, M. Kawasaki

    PHYSICAL REVIEW B　91　(24)　2015/06

    DOI： 10.1103/PhysRevB.91.241119 　

    ISSN： 1098-0121

    eISSN： 1550-235X

  71. Topological Hall effect in thin films of the Heisenberg ferromagnet EuO Peer-reviewed

    Y. Ohuchi, Y. Kozuka, M. Uchida, K. Ueno, A. Tsukazaki, M. Kawasaki

    PHYSICAL REVIEW B　91　(24)　2015/06

    DOI： 10.1103/PhysRevB.91.245115 　

    ISSN： 1098-0121

    eISSN： 1550-235X

  72. Odd-parity magnetoresistance in pyrochlore iridate thin films with broken time-reversal symmetry Peer-reviewed

    T. C. Fujita, Y. Kozuka, M. Uchida, A. Tsukazaki, T. Arima, M. Kawasaki

    SCIENTIFIC REPORTS　5　2015/05

    DOI： 10.1038/srep09711 　

    ISSN： 2045-2322

  73. Even-denominator fractional quantum Hall physics in ZnO Peer-reviewed

    J. Falson, D. Maryenko, B. Friess, D. Zhang, Y. Kozuka, A. Tsukazaki, J. H. Smet, M. Kawasaki

    NATURE PHYSICS　11　(4)　347-351　2015/04

    DOI： 10.1038/NPHYS3259 　

    ISSN： 1745-2473

    eISSN： 1745-2481

  74. Quantum Hall effect on top and bottom surface states of topological insulator (Bi1-xSbx)(2)Te-3 films Peer-reviewed

    R. Yoshimi, A. Tsukazaki, Y. Kozuka, J. Falson, K. S. Takahashi, J. G. Checkelsky, N. Nagaosa, M. Kawasaki, Y. Tokura

    NATURE COMMUNICATIONS　6　2015/04

    DOI： 10.1038/ncomms7627 　

    ISSN： 2041-1723

  75. Calibration and control of in-plane Mg doping distribution in MgxZn1-xO/ZnO heterostructures grown by molecular beam epitaxy Peer-reviewed

    Masaki Uchida, Joseph Falson, Yusaburo Segawa, Yusuke Kozuka, Atsushi Tsukazak, Masashi Kawasaki

    JAPANESE JOURNAL OF APPLIED PHYSICS　54　(2)　1-28004　2015/02

    DOI： 10.7567/JJAP.54.028004 　

    ISSN： 0021-4922

    eISSN： 1347-4065

  76. Microwave magnetoplasma resonances of two-dimensional electrons in MgZnO/ZnO heterojunctions Peer-reviewed

    V. E. Kozlov, A. B. Van'kov, S. I. Gubarev, I. V. Kukushkin, V. V. Solovyev, J. Falson, D. Maryenko, Y. Kozuka, A. Tsukazaki, M. Kawasaki, J. H. Smet

    PHYSICAL REVIEW B　91　(8)　2015/02

    DOI： 10.1103/PhysRevB.91.085304 　

    ISSN： 1098-0121

    eISSN： 1550-235X

  77. Optical probing of MgZnO/ZnO heterointerface confinement potential energy levels Peer-reviewed

    V. V. Solovyev, A. B. Van'kov, I. V. Kukushkin, J. Falson, D. Zhang, D. Maryenko, Y. Kozuka, A. Tsukazaki, J. H. Smet, M. Kawasaki

    APPLIED PHYSICS LETTERS　106　(8)　2015/02

    DOI： 10.1063/1.4913313 　

    ISSN： 0003-6951

    eISSN： 1077-3118

  78. 21aAD-10 Spin current generation with antiferromagnets

    Seki S., Ideue T., Kubota M., Kozuka Y., Nakamura M., Kaneko Y., Kawasaki M., Tokura Y.

    Meeting Abstracts of the Physical Society of Japan　70　963-963　2015

    Publisher: The Physical Society of Japan (JPS)

    DOI： 10.11316/jpsgaiyo.70.1.0_963 　

    ISSN： 2189-079X

  79. 18aCM-6 Planar Hall effect in skyrmion phase of MnSi

    Yokouchi T., Kanazawa N., Tsukazaki A., Kozuka Y., Kikkawa A., Taguchi Y., Kawasaki M., Ichikawa M., Kagawa F., Tokura Y.

    Meeting Abstracts of the Physical Society of Japan　70　923-923　2015

    Publisher: The Physical Society of Japan (JPS)

    DOI： 10.11316/jpsgaiyo.70.2.0_923 　

    ISSN： 2189-079X

  80. 17pBB-6 Quantized Hall effect in 3D topological insulator thin films

    Falson J., Checkelsky J. G.

    Meeting Abstracts of the Physical Society of Japan　70　1070-1070　2015

    Publisher: The Physical Society of Japan (JPS)

    DOI： 10.11316/jpsgaiyo.70.2.0_1070 　

    ISSN： 2189-079X

  81. 21pAH-10 Topological Hall Effect in EuO thin films

    Ohuchi Y., Kozuka Y., Uchida M., Ueno K., Tsukazaki A., Kawasaki M.

    Meeting Abstracts of the Physical Society of Japan　70　1073-1073　2015

    Publisher: The Physical Society of Japan (JPS)

    DOI： 10.11316/jpsgaiyo.70.1.0_1073 　

    ISSN： 2189-079X

  82. 21pBK-6 Magnetotransport of two-dimensional electron systems at MgZnO/ZnO under periodically modulated potential

    Tanaka Kazunari, Falson Joseph, Kozuka Yusuke, Uchida Masaki, Kubota Masashi, Maryenko Denis, Tsukazaki Atsushi, Ye Justin Jianting, Iwasa Yoshihiro, Kawasaki Masashi

    Meeting Abstracts of the Physical Society of Japan　70　1286-1286　2015

    Publisher: The Physical Society of Japan (JPS)

    DOI： 10.11316/jpsgaiyo.70.1.0_1286 　

    ISSN： 2189-079X

  83. 21pBK-5 Electric-Field Control of Landau/Zeeman Splitting in MgZnO/ZnO Quantum Hall System

    Tambo T., Falson Joseph, Kozuka Y., Uchida M., Maryenko Denis, Tsukazaki A., Kawasaki M.

    Meeting Abstracts of the Physical Society of Japan　70　1285-1285　2015

    Publisher: The Physical Society of Japan (JPS)

    DOI： 10.11316/jpsgaiyo.70.1.0_1285 　

    ISSN： 2189-079X

  84. Discretized topological Hall effect emerging from skyrmions in constricted geometry Peer-reviewed

    N. Kanazawa, M. Kubota, A. Tsukazaki, Y. Kozuka, K. S. Takahashi, M. Kawasaki, M. Ichikawa, F. Kagawa, Y. Tokura

    PHYSICAL REVIEW B　91　(4)　2015/01

    DOI： 10.1103/PhysRevB.91.041122 　

    ISSN： 1098-0121

    eISSN： 1550-235X

  85. Polarization-dependent Landau level crossing in a two-dimensional electron system in a MgZnO/ZnO heterostructure Peer-reviewed

    D. Maryenko, J. Falson, Y. Kozuka, A. Tsukazaki, M. Kawasaki

    PHYSICAL REVIEW B　90　(24)　2014/12

    DOI： 10.1103/PhysRevB.90.245303 　

    ISSN： 1098-0121

    eISSN： 1550-235X

  86. Trajectory of the anomalous Hall effect towards the quantized state in a ferromagnetic topological insulator Peer-reviewed

    J. G. Checkelsky, R. Yoshimi, A. Tsukazaki, K. S. Takahashi, Y. Kozuka, J. Falson, M. Kawasaki, Y. Tokura

    NATURE PHYSICS　10　(10)　731-736　2014/10

    DOI： 10.1038/NPHYS3053 　

    ISSN： 1745-2473

    eISSN： 1745-2481

  87. Air-gap gating of MgZnO/ZnO heterostructures Peer-reviewed

    T. Tambo, J. Falson, D. Maryenko, Y. Kozuka, A. Tsukazaki, M. Kawasaki

    JOURNAL OF APPLIED PHYSICS　116　(8)　2014/08

    DOI： 10.1063/1.4894155 　

    ISSN： 0021-8979

    eISSN： 1089-7550

  88. Electric double layer transistors with ferroelectric BaTiO3 channels Peer-reviewed

    M. Ito, Y. Matsubara, Y. Kozuka, K. S. Takahashi, F. Kagawa, J. T. Ye, Y. Iwasa, K. Ueno, Y. Tokura, M. Kawasaki

    APPLIED PHYSICS LETTERS　104　(22)　2014/06

    DOI： 10.1063/1.4881059 　

    ISSN： 0003-6951

    eISSN： 1077-3118

  89. Spontaneous polarization driven Mg concentration profile reconstruction in MgZnO/ZnO heterostructures Peer-reviewed

    K. Imasaka, J. Falson, Y. Kozuka, A. Tsukazaki, M. Kawasaki

    APPLIED PHYSICS LETTERS　104　(24)　2014/06

    DOI： 10.1063/1.4884383 　

    ISSN： 0003-6951

    eISSN： 1077-3118

  90. Challenges and opportunities of ZnO-related single crystalline heterostructures Peer-reviewed

    Y. Kozuka, A. Tsukazaki, M. Kawasaki

    APPLIED PHYSICS REVIEWS　1　(1)　2014/03

    DOI： 10.1063/1.4853535 　

    ISSN： 1931-9401

  91. Photoinduced sign inversion of the anomalous Hall effect in EuO thin films Peer-reviewed

    Y. Ohuchi, Y. Kozuka, N. Rezaei, M. S. Bahramy, R. Arita, K. Ueno, A. Tsukazaki, M. Kawasaki

    PHYSICAL REVIEW B　89　(12)　2014/03

    DOI： 10.1103/PhysRevB.89.121114 　

    ISSN： 1098-0121

    eISSN： 1550-235X

  92. Enhanced quantum oscillatory magnetization and nonequilibrium currents in an interacting two-dimensional electron system in MgZnO/ZnO with repulsive scatterers Peer-reviewed

    M. Brasse, S. M. Sauther, J. Falson, Y. Kozuka, A. Tsukazaki, Ch. Heyn, M. A. Wilde, M. Kawasaki, D. Grundler

    Physical Review B - Condensed Matter and Materials Physics　89　(7)　2014/02/18

    DOI： 10.1103/PhysRevB.89.075307 　

    ISSN： 1098-0121 1550-235X

  93. Enhanced quantum oscillatory magnetization and nonequilibrium currents in an interacting two-dimensional electron system in MgZnO/ZnO with repulsive scatterers Peer-reviewed

    M. Brasse, S. M. Sauther, J. Falson, Y. Kozuka, A. Tsukazaki, Ch. Heyn, M. A. Wilde, M. Kawasaki, D. Grundler

    PHYSICAL REVIEW B　89　(7)　2014/02

    DOI： 10.1103/PhysRevB.89.075307 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  94. Stability of two-dimensional skyrmions in thin films of Mn1-xFexSi investigated by the topological Hall effect Peer-reviewed

    T. Yokouchi, N. Kanazawa, A. Tsukazaki, Y. Kozuka, M. Kawasaki, M. Ichikawa, F. Kagawa, Y. Tokura

    PHYSICAL REVIEW B　89　(6)　2014/02

    DOI： 10.1103/PhysRevB.89.064416 　

    ISSN： 1098-0121

    eISSN： 1550-235X

  95. Recent development in ZnO related heterostructures towards optical and electrical applications

    Tsukazaki, A., Kozuka, Y., Kawasaki, M.

    Journal of the Institute of Electronics, Information and Communication Engineers　97　(3)　2014

    ISSN： 0913-5693

  96. Observation of plasma and magnetoplasma resonances of two-dimensional electrons in a single MgZnO/ZnO heterojunction Peer-reviewed

    V. E. Kozlov, A. B. Van'kov, S. I. Gubarev, I. V. Kukushkin, J. Falson, D. Maryenko, Y. Kozuka, A. Tsukazaki, M. Kawasaki, J. H. Smet

    JETP LETTERS　98　(4)　223-226　2013/10

    DOI： 10.1134/S0021364013170074 　

    ISSN： 0021-3640

    eISSN： 1090-6487

  97. Rashba spin-orbit interaction in a MgxZn1-xO/ZnO two-dimensional electron gas studied by electrically detected electron spin resonance Peer-reviewed

    Y. Kozuka, S. Teraoka, J. Falson, A. Oiwa, A. Tsukazaki, S. Tarucha, M. Kawasaki

    Physical Review B - Condensed Matter and Materials Physics　87　(20)　2013/05/07

    DOI： 10.1103/PhysRevB.87.205411 　

    ISSN： 1098-0121 1550-235X

  98. Charge-spin-coupled electrical transport properties in EuMoO 3/SrTiO3 superlattices Peer-reviewed

    T. C. Fujita, Y. Kozuka, H. Seki, M. Kawasaki

    Physical Review B - Condensed Matter and Materials Physics　87　(20)　2013/05/02

    DOI： 10.1103/PhysRevB.87.205402 　

    ISSN： 1098-0121 1550-235X

  99. Correlation-Enhanced Effective Mass of Two-Dimensional Electrons in MgxZn1-xO/ZnO Heterostructures Peer-reviewed

    Y. Kasahara, Y. Oshima, J. Falson, Y. Kozuka, A. Tsukazaki, M. Kawasaki, Y. Iwasa

    PHYSICAL REVIEW LETTERS　109　(24)　2012/12

    DOI： 10.1103/PhysRevLett.109.246401 　

    ISSN： 0031-9007

  100. Epitaxially Stabilized EuMoO3: A New Itinerant Ferromagnet Peer-reviewed

    Yusuke Kozuka, Hidenobu Seki, Takahiro C. Fujita, Suvankar Chakraverty, Kohei Yoshimatsu, Hiroshi Kumigashira, Masaharu Oshima, Mohammad S. Bahramy, Ryotaro Arita, Masashi Kawasaki

    CHEMISTRY OF MATERIALS　24　(19)　3746-3750　2012/10

    DOI： 10.1021/cm302231k 　

    ISSN： 0897-4756

    eISSN： 1520-5002

  101. Intrinsic spin-orbit coupling in superconducting delta-doped SrTiO3 heterostructures Peer-reviewed

    M. Kim, Y. Kozuka, C. Bell, Y. Hikita, H. Y. Hwang

    PHYSICAL REVIEW B　86　(8)　2012/08

    DOI： 10.1103/PhysRevB.86.085121 　

    ISSN： 1098-0121

  102. Precise calibration of Mg concentration in MgxZn1-xO thin films grown on ZnO substrates Peer-reviewed

    Y. Kozuka, J. Falson, Y. Segawa, T. Makino, A. Tsukazaki, M. Kawasaki

    JOURNAL OF APPLIED PHYSICS　112　(4)　2012/08

    DOI： 10.1063/1.4748306 　

    ISSN： 0021-8979

  103. Ultrafast optical control of magnetization in EuO thin films Peer-reviewed

    T. Makino, F. Liu, T. Yamasaki, Y. Kozuka, K. Ueno, A. Tsukazaki, T. Fukumura, Y. Kong, M. Kawasaki

    PHYSICAL REVIEW B　86　(6)　2012/08

    DOI： 10.1103/PhysRevB.86.064403 　

    ISSN： 1098-0121

  104. Temperature-Dependent Magnetotransport around nu=1/2 in ZnO Heterostructures Peer-reviewed

    D. Maryenko, J. Falson, Y. Kozuka, A. Tsukazaki, M. Onoda, H. Aoki, M. Kawasaki

    PHYSICAL REVIEW LETTERS　108　(18)　2012/05

    DOI： 10.1103/PhysRevLett.108.186803 　

    ISSN： 0031-9007

  105. Single-valley quantum Hall ferromagnet in a dilute MgxZn1-xO/ZnO strongly correlated two-dimensional electron system Peer-reviewed

    Y. Kozuka, A. Tsukazaki, D. Maryenko, J. Falson, C. Bell, M. Kim, Y. Hikita, H. Y. Hwang, M. Kawasaki

    PHYSICAL REVIEW B　85　(7)　2012/02

    DOI： 10.1103/PhysRevB.85.075302 　

    ISSN： 1098-0121

  106. High Crystallinity CuScO2 Delafossite Films Exhibiting Ultraviolet Photoluminescence Grown by Vapor-Liquid-Solid Tri-phase Epitaxy Peer-reviewed

    Yuya Matsubara, Takayuki Makino, Hiroki Hiraga, Chunlin Chen, Susumu Tsukimoto, Kazunori Ueno, Yusuke Kozuka, Yuichi Ikuhara, Masashi Kawasaki

    APPLIED PHYSICS EXPRESS　5　(1)　1-11201　2012/01

    DOI： 10.1143/APEX.5.011201 　

    ISSN： 1882-0778

  107. Magnetic and electronic properties of ordered double-perovskite La 2VMnO6 thin films Peer-reviewed

    S. Chakraverty, K. Yoshimatsu, Y. Kozuka, H. Kumigashira, M. Oshima, T. Makino, A. Ohtomo, M. Kawasaki

    Physical Review B - Condensed Matter and Materials Physics　84　(13)　2011/10/19

    DOI： 10.1103/PhysRevB.84.132411 　

    ISSN： 1098-0121 1550-235X

  108. Magnetic and electronic properties of ordered double-perovskite La2VMnO6 thin films Peer-reviewed

    S. Chakraverty, K. Yoshimatsu, Y. Kozuka, H. Kumigashira, M. Oshima, T. Makino, A. Ohtomo, M. Kawasaki

    PHYSICAL REVIEW B　84　(13)　2011/10

    DOI： 10.1103/PhysRevB.84.132411 　

    ISSN： 2469-9950

    eISSN： 2469-9969

  109. Magnesium Doping Controlled Density and Mobility of Two-Dimensional Electron Gas in MgxZn1-xO/ZnO Heterostructures Peer-reviewed

    Joseph Falson, Denis Maryenko, Yusuke Kozuka, Atsushi Tsukazaki, Masashi Kawasaki

    APPLIED PHYSICS EXPRESS　4　(9)　2011/09

    DOI： 10.1143/APEX.4.091101 　

    ISSN： 1882-0778

  110. Common Origin of the Circular-Dichroism Pattern in Angle-Resolved Photoemission Spectroscopy of SrTiO3 and CuxBi2Se3 Peer-reviewed

    Y. Ishida, H. Kanto, A. Kikkawa, Y. Taguchi, Y. Ito, Y. Ota, K. Okazaki, W. Malaeb, M. Mulazzi, M. Okawa, S. Watanabe, C. -T. Chen, M. Kim, C. Bell, Y. Kozuka, H. Y. Hwang, Y. Tokura, S. Shin

    PHYSICAL REVIEW LETTERS　107　(7)　2011/08

    DOI： 10.1103/PhysRevLett.107.077601 　

    ISSN： 0031-9007

    eISSN： 1079-7114

  111. Fermi Surface and Superconductivity in Low-Density High-Mobility delta-Doped SrTiO3 Peer-reviewed

    M. Kim, C. Bell, Y. Kozuka, M. Kurita, Y. Hikita, H. Y. Hwang

    PHYSICAL REVIEW LETTERS　107　(10)　2011/08

    DOI： 10.1103/PhysRevLett.107.106801 　

    ISSN： 0031-9007

  112. Insulating phase of a two-dimensional electron gas in MgxZn1-xO/ZnO heterostructures below v=1/3 Peer-reviewed

    Y. Kozuka, A. Tsukazaki, D. Maryenko, J. Falson, S. Akasaka, K. Nakahara, S. Nakamura, S. Awaji, K. Ueno, M. Kawasaki

    PHYSICAL REVIEW B　84　(3)　2011/07

    DOI： 10.1103/PhysRevB.84.033304 　

    ISSN： 1098-0121

  113. Enhancing the electron mobility via delta-doping in SrTiO3 Peer-reviewed

    Y. Kozuka, M. Kim, H. Ohta, Y. Hikita, C. Bell, H. Y. Hwang

    APPLIED PHYSICS LETTERS　97　(22)　2010/11

    DOI： 10.1063/1.3524198 　

    ISSN： 0003-6951

    eISSN： 1077-3118

  114. Dramatic mobility enhancements in doped SrTiO3 thin films by defect management Peer-reviewed

    Y. Kozuka, Y. Hikita, C. Bell, H. Y. Hwang

    APPLIED PHYSICS LETTERS　97　(1)　2010/07

    DOI： 10.1063/1.3457994 　

    ISSN： 0003-6951

  115. Dominant Mobility Modulation by the Electric Field Effect at the LaAlO3/SrTiO3 Interface Peer-reviewed

    C. Bell, S. Harashima, Y. Kozuka, M. Kim, B. G. Kim, Y. Hikita, H. Y. Hwang

    PHYSICAL REVIEW LETTERS　103　(22)　2009/11

    DOI： 10.1103/PhysRevLett.103.226802 　

    ISSN： 0031-9007

  116. Two-dimensional normal-state quantum oscillations in a superconducting heterostructure Peer-reviewed

    Y. Kozuka, M. Kim, C. Bell, B. G. Kim, Y. Hikita, H. Y. Hwang

    NATURE　462　(7272)　487-490　2009/11

    DOI： 10.1038/nature08566 　

    ISSN： 0028-0836

  117. Vanishing hall coefficient in the extreme quantum limit in photocarrier-doped SrTiO(3) Peer-reviewed

    Y. Kozuka, T. Susaki, H. Y. Hwang

    PHYSICAL REVIEW LETTERS　101　(9)　2008/08

    DOI： 10.1103/PhysRevLett.101.096601 　

    ISSN： 0031-9007

  118. Temperature-dependent polarity reversal in Au/Nb : SrTiO(3) Schottky junctions Peer-reviewed

    T. Susaki, Y. Kozuka, Y. Tateyama, H. Y. Hwang

    PHYSICAL REVIEW B　76　(15)　2007/10

    DOI： 10.1103/PhysRevB.76.155110 　

    ISSN： 1098-0121

  119. Optically tuned dimensionality crossover in photocarrier-doped SrTiO3: Onset of weak localization Peer-reviewed

    Y. Kozuka, Y. Hikita, T. Susaki

    PHYSICAL REVIEW B　76　(8)　2007/08

    DOI： 10.1103/PhysRevB.76.085129 　

    ISSN： 1098-0121

  120. Characterization of the Schottky barrier in SrRuO3/Nb : SrTiO3 junctions Peer-reviewed

    Y. Hikita, Y. Kozuka, T. Susaki, H. Takagi, H. Y. Hwang

    APPLIED PHYSICS LETTERS　90　(14)　2007/04

    DOI： 10.1063/1.2719157 　

    ISSN： 0003-6951

  121. Rectifying NdNiO3/Nb : SrTiO3 junctions as a probe of the surface electronic structure of NdNiO3 Peer-reviewed

    Y Kozuka, T Susaki, HY Hwang

    APPLIED PHYSICS LETTERS　88　(14)　2006/04

    DOI： 10.1063/1.2193800 　

    ISSN： 0003-6951

Show all ︎Show first 5

Misc. 39

  1. Observation of Magnetic Proximity Effect at Interfaces with Ir Oxides

    松野丈夫, 松野丈夫, 大内祐貴, 寺林真輝, 大久保晶平, 鈴木基寛, 小塚裕介, 打田正輝, 齋藤智彦, 有馬孝尚, 有馬孝尚, 十倉好紀, 十倉好紀, 川崎雅司, 川崎雅司

    SPring-8/SACLA利用研究成果集(Web)　9　(5)　2021

    ISSN： 2187-6886

  2. Observation of Magnetization Induced by Proximity Effect at SrIrO3-SrRuO3 Interfaces

    松野丈夫, 松野丈夫, 大内祐貴, 鈴木基寛, 小塚裕介, 打田正輝, 有馬孝尚, 有馬孝尚, 十倉好紀, 十倉好紀, 川崎雅司, 川崎雅司

    SPring-8/SACLA利用研究成果集(Web)　9　(1)　2021

    ISSN： 2187-6886

  3. 低キャリア濃度ディラック半金属薄膜におけるバルク量子ホール効果

    西早辰一, 打田正輝, 中澤佑介, KRIENER M., 小塚裕介, 田口康二郎, 川崎雅司, 川崎雅司

    日本物理学会講演概要集(CD-ROM)　73　(1)　2018

    ISSN： 2189-079X

  4. ディラック半金属・強磁性絶縁体接合における異常ホール効果の観測

    打田正輝, 佐藤慎, 西早辰一, 中澤佑介, KRIENER M., 小塚裕介, 田口康二郎, 川崎雅司, 川崎雅司

    日本物理学会講演概要集(CD-ROM)　73　(1)　2018

    ISSN： 2189-079X

  5. Magneto-transport study of topological phase transition in (Cd1-xZnx)3As2 thin films

    S. Nishihaya, M. Uchida, Y. Nakazawa, K. Akiba, M. Kriener, Y. Kozuka, A. Miyake, Y. Taguchi, M. Tokunaga, M. Kawasaki

    Phys. Rev. B　97　245103-1-7　2018

  6. Cd3As2薄膜における膜厚に依存した電子構造と量子輸送特性

    中澤佑介, 打田正輝, 西早辰一, 秋葉和人, KRIENER M., 小塚裕介, 三宅厚志, 田口康二郎, 徳永将史, 永長直人, 永長直人, 十倉好紀, 十倉好紀, 川崎雅司, 川崎雅司

    日本物理学会講演概要集(CD-ROM)　72　(1)　2017

    ISSN： 2189-079X

  7. Cd3As2薄膜における量子ホール効果の観測

    打田正輝, 中澤佑介, 西早辰一, 秋葉和人, KRIENER M., 小塚裕介, 三宅厚志, 田口康二郎, 徳永将史, 永長直人, 永長直人, 十倉好紀, 十倉好紀, 川崎雅司, 川崎雅司

    日本物理学会講演概要集(CD-ROM)　72　(1)　2017

    ISSN： 2189-079X

  8. Cd3As2薄膜のキャリア制御と量子ホール効果

    西早辰一, 打田正輝, 中澤佑介, KRIENER M., 小塚裕介, 田口康二郎, 川崎雅司, 川崎雅司

    日本物理学会講演概要集(CD-ROM)　72　(2)　2017

    ISSN： 2189-079X

  9. (Cd1-xZnx)3As2薄膜のカイラル異常とトポロジカル相転移

    西早辰一, 打田正輝, 中澤佑介, 秋葉和人, KRIENER M., 小塚裕介, 三宅厚志, 田口康二郎, 徳永将史, 川崎雅司, 川崎雅司

    日本物理学会講演概要集(CD-ROM)　72　(2)　2017

    ISSN： 2189-079X

  10. パルスレーザー堆積法による高品質Cd3As2薄膜の作製

    中澤佑介, 打田正輝, 西早辰一, KRIENER Markus, 小塚裕介, 田口康二郎, 川崎雅司, 川崎雅司

    応用物理学会秋季学術講演会講演予稿集(CD-ROM)　78th　2017

    ISSN： 2758-4704

  11. 走査型SQUID顕微鏡を用いたTb2Ir2O7薄膜のall-in-all-out反強磁性ドメインの可視化

    小塚裕介, 藤田貴啓, 打田正輝, 野島勉, 塚崎敦, 松野丈夫, 有馬孝尚, 有馬孝尚, 川崎雅司, 川崎雅司

    応用物理学会秋季学術講演会講演予稿集(CD-ROM)　78th　2017

    ISSN： 2758-4704

  12. 酸化物エピタキシャル界面における磁気近接効果

    松野丈夫, 松野丈夫, 大内祐貴, 鈴木基寛, 是常隆, 是常隆, 有田亮太郎, 小塚裕介, 打田正輝, 有馬孝尚, 有馬孝尚, 十倉好紀, 十倉好紀, 川崎雅司, 川崎雅司

    日本物理学会講演概要集(CD-ROM)　72　(2)　2017

    ISSN： 2189-079X

  13. Two-dimensional quantum transport in high-quality ZnO heterointerfaces.

    FALSON Joseph, 小塚裕介, 塚崎敦, 川崎雅司

    応用物理　84　(11)　984-990　2015/11/10

    ISSN： 0369-8009

  14. イオンゲートによるWO3薄膜の相変化とその空間分布

    西早辰一, 打田正輝, 小塚裕介, 岩佐義宏, 岩佐義宏, 川崎雅司, 川崎雅司

    応用物理学会秋季学術講演会講演予稿集(CD-ROM)　76th　2015

    ISSN： 2758-4704

  15. ペロブスカイト型WO3薄膜の作製とキャリアドーピング

    西早辰一, 打田正輝, 小塚裕介, 岩佐義宏, 岩佐義宏, 川崎雅司, 川崎雅司

    応用物理学会春季学術講演会講演予稿集(CD-ROM)　62nd　2015

    ISSN： 2758-4704

  16. ノンシンモルフィック半金属IrO2におけるキャリアタイプの磁場方位制御

    打田正輝, 佐野航, 高橋圭, 是常隆, 小塚裕介, 有田亮太郎, 十倉好紀, 十倉好紀, 川崎雅司, 川崎雅司

    日本物理学会講演概要集(CD-ROM)　70　(2)　2015

    ISSN： 2189-079X

  17. 8pAX-5 Ambipolar transport in top-gated FET based on topological insulator (Bi_<1-x>Sb_x)_2Te_3 thin films

    Yoshimi R., Tsukazaki A., Kozuka Y., Falson J., Takahashi K. S., Checkelsky J. G., Nagaosa N., Kawasaki M., Tokura Y.

    Meeting abstracts of the Physical Society of Japan　69　(2)　481-481　2014/08/22

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  18. 7pAV-5 占有率二3/2分数量子ホール状態の安定性と再現性(7pAV 量子ホール効果,領域4(半導体,メゾスコピック系・局在))

    Falson Joseph, Maryenko Denis, Friess Benedikt, Zhang Ding, 小塚 裕介, 塚崎 敦, Smet Jurgen, 川崎 雅司

    日本物理学会講演概要集　69　(2)　471-471　2014/08/22

    Publisher: 一般社団法人日本物理学会

    ISSN： 1342-8349

  19. 7pBG-6 Thermoelectric properties of epitaxially strained Sr_<1-x>La_xTiO_3 thin films

    Okada K. N., Fujioka J., Kozuka Y., Kawasaki M., Tokura Y.

    Meeting abstracts of the Physical Society of Japan　69　(2)　339-339　2014/08/22

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  20. 酸化物エレクトロニクスの進展と将来展望 9.ZnOヘテロ構造を用いた光・電子素子応用への展望

    塚崎敦, 小塚裕介, 川崎雅司

    電子情報通信学会誌　97　(3)　227-232　2014/03/01

    Publisher: The Institute of Electronics, Information and Communication Engineers

    ISSN： 0913-5693

  21. 光励起を用いたEuO薄膜における異常ホール効果の符号反転

    大内祐貴, 小塚裕介, REZAEI Nafise, BAHARAMY Mohammad S., BAHARAMY Mohammad S., 有田亮太郎, 有田亮太郎, 上野和紀, 上野和紀, 塚崎敦, 塚崎敦, 川崎雅司, 川崎雅司

    応用物理学会春季学術講演会講演予稿集(CD-ROM)　61st　2014

  22. Properties of TMR structures fabricated using ferromagnetic graphene nanopore arrays

    Falson Joseph, Maryenko Denis, Friess Benedikt, Zhang Ding, Kozuka Yusuke, Tsukazaki Atsushi, Smet Jurgen, Kawasaki Masashi

    Meeting abstracts of the Physical Society of Japan　68　(2)　612-612　2013/08/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  23. Octupole Magnetic Order and Magnetotransport Property in Eu_2Ir_2O_7 Thin Films

    Fujita Takahiro, Kozuka Yusuke, Tsukazaki Atsushi, Arima Taka-hisa, Kawasaki Masashi

    Meeting abstracts of the Physical Society of Japan　68　(2)　551-551　2013/08/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  24. Skyrmion Formation and topologieal Hall effect in B20-type Mn<1-x>Fe_xSi thin films

    Yokouchi T., Kanazawa N., Tsukazaki A., Kozuka Y., Kawasaki M., Uchikawa M., Kagawa F., Tokura Y.

    Meeting abstracts of the Physical Society of Japan　68　(2)　566-566　2013/08/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  25. 27pXQ-9 Mass enhancement and electron correlation in two-dimensional electron systems of ZnO

    Kasahara Y., Oshima Y., Falson Joseph, Kozuka Y., Tsukazaki A., Kawasaki M., Iwasa Y.

    Meeting abstracts of the Physical Society of Japan　68　(1)　767-767　2013/03/26

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  26. MgZnO/ZnO二次元電子系における抵抗検出型ESRによるRashbaスピン軌道相互作用の検出

    小塚裕介, FALSON Joseph, 寺岡総一郎, 大岩顕, 樽茶清悟, 塚崎敦, 川崎雅司

    応用物理学会春季学術講演会講演予稿集(CD-ROM)　60th　ROMBUNNO.28P-A8-8　2013/03/11

  27. 19aFB-7 ZnO二次元量子系におけるリエントラント整数量子ホール効果の出現(19aFB 量子ホール効果(分数量子ホール効果・核スピン),領域4(半導体,メゾスコピック系・局在))

    Falson Joseph, Maryenko Denis, 小塚 裕介, 小野 新平, 寺倉 千恵子, 塚崎 敦, 川崎 雅司

    日本物理学会講演概要集　67　(2)　625-625　2012/08/24

    Publisher: 一般社団法人日本物理学会

    ISSN： 1342-8349

  28. 25pCK-1 Surface states of Cu_xBi_2Se_3 and SrTiO_3 observed by circular-dichroism ARPES

    Ishida Y., Kanto H., Kikkawa A., Taguchi Y., Ito Y., Ota Y., Okazaki K., Malaeb Walid, Mulazzi Mattia, Okawa M., Watanabe S., Chen Chuangtian, Kim M., Bell Christopher, Kozuka Y., Hwang Halord Y., Tokura Y., Shin S.

    Meeting abstracts of the Physical Society of Japan　67　(1)　948-948　2012/03/05

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  29. Fabrication of macroscopic spin conductor using high-mobility ZnO two-dimensional interfaces

    1-5　2012

    Publisher: 旭硝子財団

    ISSN： 1882-0069

  30. 酸化亜鉛高移動度二次元電子系におけるスピン物性

    小塚 裕介, ジョセフ フォルソン, 川﨑 雅司

    Annual report = 低温センター年次報告　(4)　10-15　2012

    Publisher: 東京大学低温センター

  31. 24pGP-2 Transport and magnetic properties of new perovskite material EuMoO_3 thin films.

    Seki Hidenobu, Chakraverty Suvankar, Liu Fucai, Kozuka Yusuke, Ueno Kazunori, Makino Takayuki, Kawasaki Masashi

    Meeting abstracts of the Physical Society of Japan　66　(2)　662-662　2011/08/24

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  32. 24pTR-2 Magnesium doping controlled density and mobility of two-dimensional electron gas in Mg_xZn_<1-x>O/ZnO heterostructures

    Falson Joseph, Maryenko Denis, Kozuka Yusuke, Tsukazaki Atsushi, Kawasaki Masashi

    Meeting abstracts of the Physical Society of Japan　66　(2)　709-709　2011/08/24

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  33. 24pTR-1 Quantum Hall states of high-mobility diluted two-dimensional electrons in a MgZnO/ZnO heterostructure

    Kozuka Y., Tsukazaki A., Maryenko D., Falson J., Bell C., Kim M., Hikita Y., Hwang H. Y., Nakamura S., Awaji S., Ueno K., Kawasaki M.

    Meeting abstracts of the Physical Society of Japan　66　(2)　709-709　2011/08/24

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  34. 25aHG-2 Quantum Hall states of high-mobility diluted two-dimensional electrons in a MgZnO/ZnO heterostructure

    Kozuka Y., Tsukazaki A., Maryenko D., Falson J., Akasaka S., Nakahara K., Bell C., Hikita Y., Hwang H. Y., Nakamura S., Awaji S., Ueno K., Kawasaki M.

    Meeting abstracts of the Physical Society of Japan　66　(1)　696-696　2011/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  35. 23pXB-7 Intrinsic Spin-Orbit Coupling Effects in Symmetric δ-doped SrTiO_3 Heterostructures

    Kim M., Kozuka Y., Bell C., Hikita Y., Hwang H. Y.

    Meeting abstracts of the Physical Society of Japan　65　(2)　744-744　2010/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  36. 29pTC-6 Magnetotransport in Photo-Doped Quantum Paraelectric Semiconductors(New physics in multiple ordered systems: Strong correlation superconductors and thin film interfaces)

    Kozuka Yusuke, Hikita Yasuyuki, Susaki Tomofumi, Hwang Harold Y.

    Meeting abstracts of the Physical Society of Japan　64　(1)　632-632　2009/03/03

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  37. パルスレーザー堆積法による低濃度キャリアドープされた高移動度n型SrTiO3薄膜の作製

    小塚裕介, 大西剛, LIPPMAA M, 疋田育之, HWANG H. Y

    応用物理学会学術講演会講演予稿集　69th　(2)　510　2008/09/02

  38. 19pWG-1 Diode polarity reversal induced by temperature and electric-field dependent interface permittivity of SrTiO_3

    Susaki T., Kozuka Y., Hwang H.Y.

    Meeting abstracts of the Physical Society of Japan　62　(1)　591-591　2007/02/28

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

  39. 24pZR-2 Anomalous Magnetotransport Properties of SrTiO_3 under Illumination at Low Temperatures

    Kozuka Yusuke, Hikita Yasuyuki, Nakayama Motoshi, Susaki Tomofumi, Hwang Harold Y.

    Meeting abstracts of the Physical Society of Japan　61　(2)　478-478　2006/08/18

    Publisher: The Physical Society of Japan (JPS)

    ISSN： 1342-8349

Show all ︎Show first 5

Research Projects 6

  1. Multicaloritronics

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (S)

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

    Institution: National Institute for Materials Science

    2022/04/27 - 2027/03/31

  2. Designing spin-Hall effect based on even-odd parity hybridization of electron orbitals

    KOZUKA Yusuke

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)

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

    Institution: National Institute for Materials Science

    2019/04/01 - 2022/03/31

    More details Close

    In a non-volatile memory using a magnetic material, it is desired to reduce the power consumption in the magnetization reversal process as power consumption occurs in the magnetization reversal in the magnetic material. In this study, we aim to efficiently perform magnetization reversal using the spin Hall effect to obtain material design guidelines that consider orbital hybridization. As a result, a large nonlinear spin Hall effect is observed in the SrIrO3 thin film. Based on the first-principles calculation, we find that this is caused by the inversion symmetry breaking at the surface and interface. In addition, at the Py/Bi2WO6 interface, a large signal of inverse spin Hall effect is observed in Py by microwave irradiation. This result shows that orbital hybridization of transition metals and oxide ions play an important role.

  3. Topological conduction in magnetic oxides

    Kozuka Yusuke

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Exploratory Research

    Category: Grant-in-Aid for Challenging Exploratory Research

    Institution: The University of Tokyo

    2016/04/01 - 2018/03/31

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    For conventional spintronic elements, ferromagnetic materials have been mainly used. However, with using antiferromagnetic materials, elements with less power consumption can be fabricated owing to smaller effects of stray field. In this study, we aim at controlling magnetic domains and conducting layers at the domain boundary of pyrochlore iridates, where a spin configuration called all-in-all-out is realized. As a result, we succeeded in independently controlling the magnetic domains of each layer of a pyrochlore iridate heterostructure. In addition, we find conducting layer at the artificial magnetic domain walls. In this study, we demonstrate successful control of antiferromagnetic domains.

  4. Quantum functionalities and device applications of two-dimensional electron system at oxide interfaceshy

    Kawasaki Masashi, KOZUKA Yusuke

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (S)

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

    Institution: The University of Tokyo

    2012/05/31 - 2017/03/31

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    This research is aimed at controlling two-dimensional electrons accumulated at oxide polar interfaces and developing new quantum conduction functions. By accumulating a small amount of electrons at ZnO polar interface, We have achieved very high electron mobility over one million cm2/Vs and observed new even-demoninator fractional quantum Hall states of ν=3/2. Quantum scattering time of this system is now as high as in the top-quality GaAs two-dimensional gas. By accumulating a large amount of electrons at interfaces between ferroelectric titanate films and ionic liquids, we have demonstrated novel transistor operation with ferroelectric channel materials.

  5. Metal-insulator transition in strongly correlated diluted electron systems of high-mobility zinc oxide two-dimensional interfaces

    KOZUKA Yusuke

    Offer Organization: Japan Society for the Promotion of Science

    System: Grants-in-Aid for Scientific Research Grant-in-Aid for Research Activity Start-up

    Category: Grant-in-Aid for Research Activity Start-up

    Institution: The University of Tokyo

    2010 - 2011

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    Our aim is to observe a metal-insulator transition in two-dimensional electrons in zinc oxide by measuring electrical resistance. At ultralow temperature, by applying high magnetic field, we observed an abrupt increase in the electrical resistance, suggesting a metal-insulator transition. However, Hall resistance, which reflects carrier density, remains normal across the resistance increase. Thus, we found that a characteristic state in high-mobility diluted carrier systems is realized, which is called quantum Hall insulator

  6. 人工超格子形成による幾何学的磁気構造の設計と伝導特性の制御

    小塚 裕介

    Offer Organization: 日本学術振興会

    System: 科学研究費助成事業 特別研究員奨励費

    Category: 特別研究員奨励費

    Institution: 東京大学

    2007 - 2009

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    本研究は酸化物薄膜のバルクにはない構造制御性を利用し、酸化物ヘテロ構造中に非自明な電子的・磁気的構造を実現し磁気輸送特性を用いてその起源を解明することである。本年度は、チタン酸ストロンチウム単結晶基板上にパルスレーザー堆積法を用いて二次元界面を作製し、界面での伝導特性を評価した。特に高磁場での磁気抵抗に注目し界面での電子の量子伝導性に注目した。 まず、ドープされていないチタン酸ストロンチウム上に電子ドープチタン酸ストロンチウム薄膜を堆積し、最後にキャップ層としてドープされていないチタン酸ストロンチウムを堆積させた。この構造に対し電気抵抗の温度依存性を測定すると、非常に良い金属伝導を示し、さらに0.3K付近において超伝導を観測した。超伝導臨界磁場測定を行うことにより、ドープ層の厚さを変化させると、超伝導が二次元から三次元に転移していることがわかった。 次に、高磁場を印加し磁気抵抗を測定すると、量子伝導を示唆するシュブニコフ・ドハース振動を観測された。さらに、試料を磁場に対して回転させてシュブニコフ・ドハース振動を測定すると、その周期は磁場の試料に垂直成分のみに依存しフェルミ面が二次元的であることを示している。このように超伝導を示す物質でその常伝導状態が高移動度二次元フェルミ面から成っている物質の観測は初めてである。 以上の結果は、酸化物の多彩な物性を組み合わせてヘテロ構造を作製することによって可能となった。今回の成果は酸化物におけるメゾスコピック系という新しい分野の先駆的研究である。

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Teaching Experience 1

  1. 力学（A)　東京大学