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岡村さんの写真

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岡村 嘉大 Yoshihiro Okamura

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Biography
2008-3 私立開成高校卒業
2012-3 東京大学工学部物理工学科 卒業
2014-3 東京大学大学院工学系研究科物理工学専攻 修士課程 修了
2017-3 東京大学大学院工学系研究科物理工学専攻 博士課程 修了
日本学術振興会 特別研究員(DC1)
2017-4より 東京大学大学院工学系研究科量子相エレクトロニクスセンター 助教
okamura"at"ap.t.u-tokyo.ac.jp
"at"を@に変更してください
Original papers
  1. "Emergence of ferroelectric topological insulator as verified by quantum Hall effect of surface states in (Sn,Pb,In)Te films"
    R. Yoshimi, R. Kurihara, Y. Okamura, H. Handa, N. Ogawa, M. Kawamura, A. Tsukazaki, K. S. Takahashi, M. Kawasaki, Y. Takahashi, M. Tokunaga, and Y. Tokura
    arXiv:2411.17263
  2. "Gapped nodal planes drive a large topological Nernst effect in a chiral lattice antiferromagnet"
    N. D. Khanh, S. Minami, M. Hirschmann, T. Nomoto, M. C. Jiang, R. Yamada, D. Yamaguchi, Y. Hayashi, Y. Okamura, H. Watanabe, G. Y. Guo, Y. Takahashi, S. Seki, Y. Taguchi, Y. Tokura, R. Arita, and M. Hirschberger
    Nat. Commun. in press
  3. "Synthesis of a tailored semimetallic Weyl ferromagnet"
    I. Belopolski, R. Watanabe, Y. Sato, R. Yoshimi, M. Kawamura, S. Nagahama, Y. Zhao. S. Shao, Y. Jin, Y. Kato, Y. Okamura, X-X. Zhang, Y. Fujishiro, Y. Takahashi, M. Hirschberger, A. Tsukazaki, K. S. Takahashi, C-K. Chiu, G. Chang, M. Kawasaki, N. Nagaosa, and Y. Tokura
    Nature in press.
  4. "Terahertz photon to dc current conversion via magnetic excitations of multiferroics"
    M. Ogino, Y. Okamura, K. Fujiwara, T. Morimoto, N. Nagaosa, Y. Kaneko, Y. Tokura, and Y. Takahashi
    Nature Communications 15, 4699 (2024).
  5. "Large nonlinear optical magnetoelectric response in a noncentrosymmetric magnetic Weyl semimetal"
    K. Shoriki*, K. Moriishi*, Y. Okamura*, K. Yokoi, H. Usui, H. Murakawa, H. Sakai, N. Hanasaki, Y. Tokura, and Y. Takahashi (*equal contribution)
    Proceedings of the National Academy of Sciences of the United States of America 121, e2316910121 (2024).
  6. "Terahertz field driven giant nonlinear phonon response in ferroelectric semicondutor In-doped (Sn,Pb)Te"
    H. Handa, Y. Okamura, R. Yoshimi, A. Tsukazaki, K. S. Takahashi, Y. Tokura, and Y. Takahashi
    Phys. Rev. B 109, L081102 (2024).
  7. "Observation of anomalous Hall resonance of massive Dirac fermions in topological kagome-lattice magnet"
    Y. Okamura, K. Shoriki, Y. Nomura, Y. Fujishiro, A. Kitaori, N. Kanazawa, R. Arita, Y. Tokura, and Y. Takahashi
    npj Quantum Materials 8, 57 (2023).
  8. "Topological magneto-optical effect from skyrmion lattice"
    Y. D. Kato, Y. Okamura, M. Hirschberger, Y. Tokura, and Y. Takahashi
    Nature Communications 14, 5416 (2023).
  9. "Band structures in orientation-controlled CuI thin films under epitaxial strain"
    M. Nakamura, S. Inagaki, Y. Okamura, M. Ogino, Y. Takahashi, K. Adachi, D. Hashizume, Y. Tokura, and M. Kawasaki
    Physical Review B 106, 125307 (2022).
  10. "Terahertz lattice and charge dynamics in ferroelectric semiconductor SnxPb1-xTe"
    Y. Okamura, H. Handa, R. Yoshimi, A. Tsukazaki, K. S. Takahashi, M. Kawasaki, Y. Tokura, and Y. Takahashi
    npj Quantum Materials 7, 91 (2022).
  11. "Optical anomalous Hall effect enhanced by flat bands in ferromagnetic van der Waals semimetal"
    Y. D. Kato, Y. Okamura, S. Minami, R. Fujimura, M. Mogi, R. Yoshimi, A. Tsukazaki, K. Takahashi, M. Kawasaki, R. Arita, Y. Tokura, and Y. Takahashi
    npj Quantum Materials 7, 73 (2022).
  12. "Photovoltaic effect by soft phonon excitation"
    Y. Okamura, T. Morimoto, N. Ogawa, Y. Kaneko, G-Y. Guo, M. Kawasaki, N. Naogaosa, Y. Tokura, and Y. Takahashi
    Proceedings of the National Academy of Sciences of the United States of America 119, e2122313119 (2022).
  13. "Experimental signature of parity anomaly in semi-magnetic topological insulator"
    M. Mogi, Y. Okamura, M. Kawamura, R. Yoshimi, K. Yasuda, A. Tsukazaki, K. S. Takahashi, T. Morimoto, N. Nagaosa, M. Kawasaki, Y. Takahashi, and Y. Tokura
    Nature Physics 18, 390 (2022).
  14. "Magneto-optical spectroscopy on Weyl nodes for anomalous and topological Hall effects in chiral MnGe"
    Y. Hayashi, Y. Okamura, N. Kanazawa, T. Yu, T. Koretsune, R. Arita, A. Tsukazaki, M. Ichikawa, M Kawasaki, Y. Tokura and Y. Takahashi
    Nature Communications 12, 5974 (2021).
  15. "Heteroepitaxial growth of wide bandgap cuprous iodide films exhibiting clear free-exciton emission"
    S. Inagaki, M. Nakamura, Y. Okamura, M. Ogino, Y. Takahashi, L. C. Peng, X. Z. Yu, Y. Tokura, and M. Kawasaki,
    Applied Physics Letters 118, 012103 (2021).
  16. "Giant magneto-optical responses in magnetic Weyl semimetal Co3Sn2S2"
    Y. Okamura, S. Minami, Y. Kato, Y. Fujishiro, Y. Kaneko, J. Ikeda, J. Muramoto, R. Kaneko, K. Ueda, V. Kocsis, Y. Taguchi, T. Koretsune, K. Fujiwara, A. Tsukazaki, R. Arita, Y. Tokura and Y. Takahashi,
    Nature Communications 11, 4619 (2020).
  17. "Propagation dynamics of spin excitations along skyrmion strings"
    S. Seki, M. Garst, J. Waizner, R. Takagi, Y. Okamura, K. Kondou, F. Kagawa, Y. Otani, and Y. Tokura,
    Nature Communications 11, 256 (2020).
  18. "Element-specific soft x-ray spectroscopy, scattering and imaging studies of the skyrmion-hosting compound Co8Zn8Mn4"
    V. Ukleev, Y. Yamasaki, D. Morikawa, K. Karube, K. Shibata, Y. Tokunaga, Y. Okamura, K. Amemiya, M. Valvidares, H. Nakao, Y. Taguchi, Y. Tokura, and T. Arima,
    Physical Review B 99, 144408 (2019).
  19. "Microwave directional dichroism resonant with spin excitations in the polar ferromagnet GaV4S8"
    Y. Okamura, S. Seki, S. Bordacs, A. Butykai, V. Tsurkan, I. Kezsmarki, and Y. Tokura
    Phys. Rev. Lett. 122, 057202 (2019).
  20. "Coherent resonant soft X-ray scattering study of magnetic textures in FeGe"
    V. Ukleev, Y. Yamasaki, D. Morikawa, N. Kanazawa, Y. Okamura, H. Nakao, Y. Tokura, T. Arima
    Quantum Beam Science 2, 3 (2018).
  21. "Stabilization of magnetic skyrmions by uniaxial tensile strain"
    S. Seki, Y. Okamura, K. Shibata, R. Takagi, N. D. Khahn, F. Kagawa, T. Arima, and Y. Tokura
    Phys. Rev. B 96, 220404 (2017).
  22. "Emergence and magnetic-field variation of chiral-soliton lattice and skyrmion lattice in the strained helimagnet Cu2OSeO3"
    Y. Okamura, Y. Yamasaki, D. Morikawa, T. Honda, V. Ukleev, H. Nakao, Y. Murakami, K. Shibata, F. Kagawa, S. Seki, T. Arima, and Y. Tokura
    Phys. Rev. B 96, 174417 (2017).
  23. "Current-induced viscoelastic topological unwinding of metastable skyrmion strings"
    F. Kagawa, H. Oike, W. Koshibae, A. Kikkawa, Y. Okamura, Y. Taguchi, N. Nagaosa, and Y. Tokura
    Nat. Commun. 8, 1332 (2017).
  24. "Directional electric-field induced transformation from skyrmion lattice to distinct helices in multiferroic Cu2OSeO3"
    Y. Okamura, Y. Yamasaki, D. Morikawa, T. Honda, V. Ukleev, H. Nakao, Y. Murakami, K. Shibata, F. Kagawa, S. Seki, T. Arima, and Y. Tokura
    Phys. Rev. B 95, 184411 (2017).
  25. "Transition to and from the skyrmion lattice phase by electric fields in a magnetoelectric compound"
    Y. Okamura, F. Kagawa, S. Seki, and Y. Tokura
    Nat. Commun. 7, 12669 (2016).
  26. "Magnetochiral nonreciprocity of volume spin wave propagation in chiral-lattice ferromagnets"
    S. Seki, Y. Okamura, K. Kondou, K. Shibata, M. Kubota, R. Takagi, F. Kagawa, M. Kawasaki, G. Tatara, Y. Otani, and Y. Tokura
    Phys. Rev. B 93, 235131 (2016).
  27. "Microwave magnetochiral dichroism in the chiral-lattice magnet Cu2OSeO3"
    Y. Okamura, F. Kagawa, M. Mochizuki, M. Kubota, S. Seki, S. Ishiwata, M. Kawasaki, Y. Onose, and Y. Tokura
    Phys. Rev. Lett. 114, 197202 (2015).
  28. "Microwave magnetoelectric effect via skyrmion resonance in a helimagnetic multiferroic"
    Y. Okamura, F. Kagawa, M. Mochizuki, M. Kubota, S. Seki, S. Ishiwata, M. Kawasaki, Y. Onose, and Y. Tokura
    Nat. Commun. 4, 2391 (2013).
  29. "Observation of Magnetic excitation of Skyrmion Crystal in a Helimagnec Insulator Cu2OSeO3"
    Y. Onose, Y. Okamura, S. Seki, S. Ishiwata, and Y. Tokura
    Phys. Rev. Lett. 109, 037603 (2012).
国際会議発表
  1. "Large terahertz resonance in MnGe thin film" (APS March Meeting, Boston, America, March 2019) Y. Okamura, Y. Hayashi, N. Kanazawa, A. Tsukazaki, M. Kawasaki, M. Ichikawa, Y. Tokura, Y. Takahashi
  2. "Microwave magnetochiral dichroism in chiral-lattice magnet Cu2OSeO3"
    (Workshop on "Topological Magnets" Wako Saitama Japan, May 2015)
    Y. Okamura, F. Kagawa, S. Seki,M. Kubota, M. Kawasaki, and Y. Tokura
  3. "Microwave magnetochiral dichroism resonant with electromagnons in a chiral-lattice magnet Cu2OSeO3"
    (APS March Meeting San Antonio America, March 2015)
    Y. Okamura, F. Kagawa, S. Seki,M. Kubota, M. Kawasaki, and Y. Tokura
  4. "Microwave magnetoelectric effect via skyrmion resonance in a helimagnetic multiferroic"
    (The 12th Asia Pacific Physics Conference A-1 Makuhari Chiba Japan, July 2013)
    Y. Okamura, F. Kagawa, M. Mochizuki, M. Kubota, S. Seki, S. Ishiwata, M. Kawasaki, Y. Onose and Y. Tokura
特許
1.公開:特開 2015-100083 (平 27.5.28)
出願:特願 2013-240064 (平 25.11.20)
出願種別(通常)
名称:電磁波の透過率制御方法、電磁波の透過率制御デバイス
出願人:国立研究開発法人理化学研究所, ローム株式会社
発明者氏名:岡村嘉大、賀川史敬、関真一郎、久保田将司、石渡晋太郎、小野瀬佳文、望月維人、十倉好紀、川崎雅司
受賞
2011年度 東京大学物理工学科 優秀卒業論文賞
2013年度 田中昭二賞、修士課程工学系研究科長賞
2016年度 放射光学会学生発表賞
2017年度 博士課程工学系研究科長賞


研究助成
  1. 基盤研究B(2024-2026年度)
  2. 挑戦的研究(萌芽)(2022-2023年度)
  3. 新学術領域研究(研究領域提案型)「量子液晶の物性科学」(2022-2023年度)
  4. 若手研究(2019-2020年度)
  5. スタートアップ(2017-2018年度)
  6. 日本学術振興会特別研究員
財団助成
  1. 光科学技術財団(2025年度)
  2. 三菱財団(2024年度)
  3. 旭硝子財団(2023年度)
  4. 池谷財団(2023年度)
  5. 村田財団(2022年度)
  6. みずほ学術振興会財団(2020-2021年度)
  7. 村田財団(2018-2019年度)