独立行政法人理化学研究所 基幹研究所 物質機能創成研究領域 交差相関物性科学研究グループ

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奥山大輔

氏名

researcherID

奥山 大輔

研究分野

X線・中性子を使った散乱実験

略歴

1978年7月 大阪府生まれ
2002年3月 千葉大学理学部 卒業
2007年3月 東北大学大学院理学研究科物理学専攻 博士課程修了 博士(理学)
2007年4月 科学技術振興機構 ERATO 十倉マルチフェロイックスプロジェクト 研究員
2008年1月 理化学研究所 交差相関物性科学研究グループ 交差相関物質研究チーム 研究員
(2008年4月より名称変更)
理化学研究所 基幹研究所 物質機能創成研究領域
交差相関物性科学研究グループ 交差相関物質研究チーム 基幹研究所研究員

学会活動・社会貢献

日本物理学会会員、放射光学会会員

研究業績内容

X線及び中性子を用いた散乱実験より、物質の構造を探る事をメインに行っている。

主要な業績
2006年 3月平成17年度青葉理学振興会賞(東北大学理学研究科)
2007年 3月平成18年度総長賞(東北大学)

主な論文・業績

  1. K. Shibuya, D. Okuyama, R. Kumai, Y. Yamasaki, H. Nakao, Y. Murakami, Y. Taguchi, T. Arima, M. Kawasaki and Y. Tokura,
    "X-ray induced insulator-metal transition in a thin film of electron-doped VO2"
    Phys. Rev. B. 84, 165108-1-6 (2011).
  2. H. Sakai, J. Fujioka, T. Fukuda, D. Okuyama, D. Hashizume, F. Kagawa, H. Nakao, Y. Murakami, T. Arima, A. Q.R. Baron, Y. Taguchi and Y. Tokura,
    "Displacement-Type Ferroelectricity with Off-Center Magnetic Ions in Perovskite Sr1-xBaxMnO3"
    Phys. Rev. Lett. 107, 137601-1-5 (2011).
  3. S. Chakraverty, A. Ohtomo, D. Okuyama, M. Saito, M. Okuda, R. Kumai, T. Arima, Y. Tokura, S. Tsukimoto, and M. Kawasaki,
    "Ferrimagnetism and spontaneous ordering of transition metals in double perovskite La2CrFeO6 films"
    Phys. Rev. B. 84, 064436-1-5 (2011).
  4. Y. Tokunaga, D. Okuyama, T. Kurumaji, T. Arima, H. Nakao, Y. Murakami, Y. Taguchi and Y. Tokura,
    "Multiferroicity in NiBr2 with long-wavelength cycloidal spin structure on a triangular lattice"
    Phys. Rev. B. 84, 060406(R)-1-4 (2011).
  5. D. Okuyama, S. Ishiwata, Y. Takahashi, K. Yamauchi, S. Picozzi, K. Sugimoto, H. Sakai, M. Takata, R. Shimano, Y. Taguchi, T. Arima, and Y. Tokura,
    "Magnetically driven ferroelectric atomic displacements in orthorhombic YMnO3"
    Phys. Rev. B. 84, 054440-1-7 (2011).
  6. S. Ishiwata, M. Tokunaga, Y. Kaneko, D. Okuyama, Y. Tokunaga, S. Wakimoto, K. Kakurai, T. Arima, Y. Taguchi, and Y. Tokura,
    "Versatile helimagnetic phases under magnetic fields in cubic perovskite SrFeO3"
    Phys. Rev. B 84, 054427-1-5 (2011).
  7. T. Matsumura, D. Okuyama, T. Mouri, and Y. Murakami,
    "Successive Magnetic Phase Transitions of Component Orderings in DyB4"
    J. Phys. Soc. Jpn. 80, 074701-1-9 (2011).
  8. Y. Yamasaki, D. Okuyama, M. Nakamura, T. Arima, M. Kawasaki, Y. Tokura, T. Kimura, and Y. Wakabayashi,
    "Interfacial structure of manganite superlattice"
    J. Phys. Soc. Jpn. 80, 073601-1-4 (2011).
  9. Y. Krockenberger, J. S. Lee, D. Okuyama, H. Nakao, Y. Murakami, M. Kawasaki, and Y. Tokura,
    "Garnet superlattice as a transparent above-room-temperature polar magnet"
    Phys. Rev. B 83, 214414-1-5(2011).
  10. N. Kanazawa, Y. Onose, T. Arima, D. Okuyama, K. Ohoyama, S. Wakimoto, K. Kakurai, S. Ishiwata, and Y. Tokura,
    "Large topological Hall effect in a short-period helimagnet MnGe"
    Phys. Rev. Lett. 106, 156603-1-4 (2011).
  11. Y. Tokunaga, Y. Kaneko, D. Okuyama, S. Ishiwata, T. Arima, S. Wakimoto, K. Kakurai, Y. Taguchi, and Y. Tokura,
    "Multiferroic M-type Hexaferrites with a Room-Temperature Conical State and Magnetically Controllable Spin Helicity"
    Phys. Rev. Lett. 105, 257201-1-4 (2010).
  12. H. Sakai, S. Ishiwata, D. Okuyama, A. Nakao, H. Nakao, Y. Murakami, Y. Taguchi, and Y. Tokura,
    "Electron doping in the cubic perovskite SrMnO3: Isotropic metal versus chainlike ordering of Jahn-Teller polarons"
    Phys. Rev. B 82, 180409(R)-1-4 (2010).
  13. J. S. Lee, M. Nakamura, D. Okuyama, R. Kumai, T. Arima, M. Kawasaki, and Y. Tokura,
    "Competing electronic orders of manganite thin films"
    Phys. Rev. B 82, 052406-1-4 (2010).
  14. S. Ishiwata, D. Okuyama, K. Kakurai, M. Nishi, Y. Taguchi, and Y. Tokura,
    "Neutron diffraction studies on multiferroic conical magnet Ba2Mg2Fe12O22"
    Phys. Rev. B 81, 174418-1-8 (2010).
  15. H. Sagayama, N. Abe, K. Taniguchi, T. Arima, Y. Yamasaki, D. Okuyama, Y. Tokura, S. Sakai, T. Morita, T. Komesu, H. Ohsumi, and M. Takata,
    "Observation of Spin Helicity Using Nonresonant Circularly Polarized X-ray Diffraction Analysis "
    J. Phys. Soc. Jpn. 79, 043711-1-4 (2010).
  16. M. Nakamura, D. Okuyama, J. S. Lee, T. Arima, Y. Wakabayashi, R. Kumai, M. Kawasaki, and Y. Tokura,
    "Magenetically Tunable Metal-Insulator Superlattices"
    Adv. Mater. 22, 500-504 (2010).
  17. N. Kida, D. Okuyama, S. Ishiwata, Y. Taguchi, R. Shimano, K. Iwasa, T. Arima, and Y. Tokura,
    "Electric-dipole-active resonance in the conical-spin magnet Ba2Mg2Fe12O22"
    Phys. Rev. B 80, 220406-1-4 (2009).
  18. D. Okuyama, M. Nakamura, Y. Wakabayashi, H. Itoh, R. Kumai, H. Yamada, Y. Taguchi, T. Arima, M. Kawasaki, and Y. Tokura,
    "Epitaxial-strain effect on charge/orbital order in Pr0.5Ca0.5MnO3 films"
    Appl. Phys. Lett. 95, 152502-1-3 (2009).
  19. D. Okuyama, Y. Tokunaga, R. Kumai, Y. Taguchi, T. Arima, and Y. Tokura,
    "Lattice-form dependent orbital shape and charge disproportionation in charge- and orbital-ordered manganites"
    Phys. Rev. B 80, 064402-1-8 (2009).
  20. T. Inami, K. Ohwada, Y. H. Matsuda, Z. W. Ouyang, H. Nojiri, T. Matsumura, D. Okuyama, and Y. Murakami,
    "Reasonant Magnetic X-ray Diffraction Study on Successive Metamagnetic Transition in TbB4"
    J. Phys. Soc. Jpn. 78, 033707-1-4 (2009).
  21. Y. Yamasaki, H. Sagayama, N. Abe, T. Arima, K. Sasai, M. Matsuura, K. Hirota, D. Okuyama, Y. Noda, and Y. Tokura,
    "Cycloidal Spin Order in the a-Axis Polarized Ferroelectric Phase of Orthorhombic Perovskite Manganite"
    Phys. Rev. Lett. 101, 097204-1-4 (2008).
  22. D. Okuyama, T. Matsumura, T. Mouri, N. Ishikawa, K. Ohoyama, H. Hiraka, H. Nakao, K. Iwasa, and Y. Murakami,
    "Competition of Magnetic and Quadrupolar Order Parameters in HoB4"
    J. Phys. Soc. Jpn. 77, 044709-1-14 (2008).
  23. T. Matsumura, D. Okuyama, S. Niioka, H. Isida, T. Satoh, Y. Murakami, H. Toyosaki, Y. Yamada, T. Fukumura and M. Kawasaki,
    "X-ray Anomalous Scattering of Diluted Magnetic Oxide Semiconductors: Possible Evidence of Lattice Deformation for High Temperature Ferromagnetism"
    Phys. Rev. B 76, 115320-1-5 (2007).
  24. D. Okuyama, T. Matsumura, K. Iwasa, and Y. Murakami,
    "Magnetic Phase Transition in HoB4 Studied by Neutron Diffraction"
    J. Magn. Magn. Matter. 310, e152-e154 (2007).
  25. T. Matsumura, D. Okuyama, and Y. Murakami,
    "Non-Collinear Magnetic Structure of TbB4"
    J. Phys. Soc. Jpn. 76, 015001-1-2 (2007).
  26. D. Okuyama, T. Matsumura, H. Nakao, and Y. Murakami,
    "Quadrupolar Order and Structural Phase Transition in DyB4 with Geometrical Frustration"
    J. Phys. Soc. Jpn. 75, Suppl. 198-200 (2006).
  27. D. Okuyama, T. Matsumura, H. Nakao, Y. Murakami, Y. Wakabayashi, A. Tobo, and H. Onodera,
    "Field-induced Antiferroquadrupolar Order in TbB2C2 Observed by Resonant X-ray Scattering"
    Physica B 378-380 488-489 (2006).
  28. M. Sakata, A. Tobo, T. Matsumura, D. Okuyama, Y. Murakami, Y. Wakabayashi, H. Sawa, K. Ohoyama, and H. Onodera,
    "Resonant X-ray scattering on antiferroquadrupolar ordering compound Dy0.8Gd0.2B2C2"
    Physica 359-361 950-952 (2005).
  29. D. Okuyama, T. Matsumura, H. Nakao, and Y. Murakami,
    "Quadrupolar Frustration in Shastry-Sutherland Lattice of DyB4 Studied by Resonant X-ray Scattering"
    J. Phys. Soc. Jpn. 74, 2434-2437 (2005).
  30. D. Okuyama, T. Matsumura, H. Nakao, Y. Murakami, H. Onodera, A. Tobo, Y. Wakabayashi, and H. Sawa,
    "Periodic Arrangement of Quadrupolar Moments Induced by the Antiferromagnetic Order in TbB2C2: Observation by Resonant X-ray Scattering"
    J. Phys. Soc. Jpn. 74, 1566-1571 (2005).
  31. T. Matsumura, D. Okuyama, N. Oumi, K. Hirota, H. Nakao, Y. Murakami, and Y. Wakabayashi,
    "Multipole Tensor Analysis of the Resonant X-ray Scattering by Quadurpolar and Magnetic Order in DyB2C2"
    J. Phys. Soc. Jpn. 74, 1500-1507 (2005).
  32. T. Matsumura, D. Okuyama, N. Oumi, K. Hirota, H. Nakao, Y. Murakami, and Y. Wakabayashi,
    "d-f Coulomb and quadrupole-strain interaction in DyB2C2 observed by resonant x-ray scattering"
    Phys. Rev. B 71, 012405-1-4 (2005).
  33. D. Okuyama, T. Matsumura, Y. Murakami, Y. Wakabayashi, H. Sawa, and D. X. Li,
    "Resonant magnetic X-ray scattering from antiferromagnetic order in GdAs"
    Physica
    B 345 63-65 (2004).