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奥山大輔 researcherID

氏名

奥山 大輔

E-mail

okudaisu[at]tagen.tohoku.ac.jp

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 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 研究員
2012年4月 理化学研究所 基幹研究所 物質機能創成研究領域 研究員
2014年4月 東北大学 多元物質科学研究所 スピン量子物性研究分野 助教

学会活動・社会貢献

日本物理学会会員、放射光学会会員、中性子科学会会員

放射光学会編集委員(2015.9-2017.9)

研究業績内容

中性子及びX線を用いた散乱実験より、物質の静的/動的構造を探る。

主要な業績
・軌道フラストレーション系における磁気・軌道秩序構造の決定
・マルチフェロイックス物質の静的及び動的な結晶/磁気構造の決定
・薄膜試料で電気抵抗及び結晶構造の劇的な変化を伴うX線誘起相転移を発見
・液体ゲートデバイスにおけるオペランドX線回折/吸収分光測定技術の開発
・立方晶の希土類化合物で初めてカイラル磁性体を発見

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)

論文・業績

  1. Y. Shiomi, R. Takashima, D. Okuyama, G. Gitgeatpong, P. Piyawongwatthana, K. Matan, T. J. Sato, E. Saitoh,
    "Spin Seebeck effect in the polar antiferromagnet α-Cu2V2O7"
    Phys. Rev. B 96, 180414(R)-1-180414(R)-5 (2017).
  2. R. Yamagishi, T. Kojima, S. Kameoka, D. Okuyama, T.J. Sato, C. Nishimura, A.P. Tsai,
    "Creating the hydrogen absorption capability of CeNi5 through the addition of Al"
    International J. Hydrogen Energy 42, 21832-21840 (2017).
  3. K. Makino, J. D. Reim, D. Higashi, D. Okuyama, T. J. Sato, Y. Nambu, E. P. Gilbert, N. Booth, S. Seki, Y. Tokura,
    "Thermal stability and irreversibility of skyrmion-lattice phases in Cu2OSeO3"
    Phys. Rev. B 95, 134412-1-134412-10 (2017).
  4. J. D. Reim, K. Makino, D. Higashi, Y. Nambu, D. Okuyama, T. J Sato, E. P. Gilbert, N. Booth, S. Seki,
    "Impact of minute-time-scale kinetics on the stabilization of the skyrmion-lattice in Cu2OSeO3"
    J. Phys.: Conf. Ser. 828, 1-7 (2017).
  5. T. J. Sato, D. Okuyama, H. Kimura,
    "Tiny adiabatic-demagnetization refrigerator for a commercial superconducting quantum interference device magnetometer"
    Rev. Sci. Instrum. 87, 123905-1-123905-7 (2016).
  6. T. J. Sato, D. Okuyama, T. Hong, A. Kikkawa, Y. Taguchi, T. Arima, Y. Tokura,
    "Magnon dispersion shift in the induced ferromagnetic phase of noncentrosymmetric MnSi"
    Phys. Rev. B 84, 144420-1-144420-7 (2016).
  7. K. Makino, D. Okuyama, M. Avdeev, T. J. Sato,
    "Incommensurate Magnetic Structure in the Cubic Noncentrosymmetric Ternary Compound Pr5Ru3Al2"
    J. Phys. Soc. Jpn. 85, 073705-1-5 (2016).
  8. K. Z. Takahashi, D. Okuyama, and T. J. Sato,
    "Utilization of mechanical alloying method for flux growth of single crystalline BaFe2(As1-xPx)2"
    J. Cryst. Growth 446, 446,39-41 (2016).
  9. J. Fujioka, A. Doi, D. Okuyama, D. Morikawa, T. Arima, K. N. Okada, Y. Kaneko, T. Fukuda, H. Uchiyama, D. Ishikawa, A. Q. R. Baron, K. Kato, M. Takata, and Y. Tokura,
    "Ferroelectric-like metallic state in electron doped BaTiO3"
    Scientific Reports 5, 13207-1-9 (2015).
  10. M. Nakano, D. Okuyama, K. Shibuya, M. Mizumaki, H. Ohsumi, M. Yoshida, M. Takata, M. Kawasaki, Y. Tokura, T. Arima, and Y. Iwasa,
    "Distinct substrate effect on the reversibility of the metal-insulator transitions in electrolyte-gated VO2 thin films"
    Adv. Electron. Mater. 1, 1500093-1-7 (2015).
  11. S. Tardif, S. Takeshita, H. Ohsumi, J. Yamaura, D. Okuyama, Z. Hiroi, M. Takata, and T. Arima,
    "All-in-all-out magnetic domains: X-ray diffraction imaging and magnetic field control"
    Phys. Rev. Lett. 114, 147205-1-5 (2015).
  12. D. Okuyama, K. Shibuya, R. Kumai, T. Suzuki, Y. Yamasaki, H. Nakao, Y. Murakami, M. Kawasaki, Y. Taguchi, Y. Tokura, and T. Arima,
    "X-ray study of metal-insulator transitions induced by W doping and photoirradiation in VO2 films"
    Phys. Rev. B 91, 064101-1-8 (2015).
  13. A. Doi, J. Fujioka, T. Fukuda, S. Tsutsui, D. Okuyama, Y. Taguchi, T. Arima, A. Q. R. Baron, and Y. Tokura,
    "Multi-spin-state dynamics during insulator-metal crossover in LaCoO3"
    Phys. Rev. B 90, 081109(R)-1-4 (2015).
  14. D. Okuyama, M. Nakano, S. Takashita, H. Ohsumi, S. Tardif, K. Shibuya, T. Hatano, S. Ono, H. Yumoto, T. Koyama, H. Ohashi, M. Takata, Y. Taguchi, M. Kawasaki, T. Arima, Y. Iwasa, and Y. Tokura,
    "Gate-tunable gigantic lattice deformation in VO2"
    Appl. Phys. Lett. 104, 023507 (2014).
  15. D. Choudhury, T. Suzuki, D. Okuyama, D. Morikawa, K. Kato, M. Takata, K. Kobayashi, R. Kumai, H. Nakao, Y. Murakami, M. Bremholm, B. B. Iversen, T. Arima, Y. Tokura, and Y. Taguchi,
    "Evolution of magnetic and structural transitions and enhancement of magnetocaloric effect in Fe1-xMnxV2O4"
    Phys. Rev. B 89, 104427-1-6 (2014).
  16. 奥山大輔, 渋谷圭介, 熊井玲児, 山崎裕一, 中尾裕則, 村上洋一, 田口康二郎, 有馬孝尚, 川崎雅司, 十倉好紀,
    "WドープVO2薄膜における絶縁体から金属への相変化を伴うX線誘起構造相転移"
    日本放射光学会誌 26, 309-316 (2013).
  17. H. Sakai, J. Fujioka, T. Fukuda, M. S. Bahramy, D. Okuyama, R. Arita, T. Arima, A. Q. R. Baron, Y. Taguchi, and Y. Tokura,
    "Soft phonon mode coupled with antiferromagnetic order in incipient-ferroelectric Mott insulators Sr1-xBax MnO3"
    Phys. Rev. B 86, 104407-1-11 (2012).
  18. M. Nakano, K. Shibuya, D. Okuyama, T. Hatano, M. Kawasaki, Y. Iwasa and Y. Tokura,
    "Collective bulk carrier delocalization driven by electrostatic surface charge accumulation"
    Nature 487, 459-462 (2012).
  19. Y. Taguchi, H. Sakai, D. Okuyama, S. Ishiwata, J. Fujioka, T. Fukuda, D. Hashizume, F. Kagawa, Y. Takahashi, R. Shimano, Y. Tokunaga, Y. Kaneko, A. Nakao, H. Nakao, Y. Murakami, K. Sugimoto, M. Takata, K. Yamauchi, S. Picozzi, A. Q. R. Baron, T. Arima and Y. Tokura,
    "Emergent phenomena in perovskite-type manganites"
    Physica B 407, 1685-1688 (2012).
  20. 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).
  21. 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).
  22. 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).
  23. 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).
  24. 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).
  25. 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).
  26. 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).
  27. 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).
  28. 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).
  29. 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).
  30. 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).
  31. 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).
  32. 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).
  33. 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).
  34. 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).
  35. 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).
  36. 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).
  37. 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).
  38. 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).
  39. 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).
  40. 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).
  41. 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).
  42. 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).
  43. 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).
  44. T. Matsumura, D. Okuyama, and Y. Murakami,
    "Non-Collinear Magnetic Structure of TbB4"
    J. Phys. Soc. Jpn. 76, 015001-1-2 (2007).
  45. 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).
  46. 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).
  47. 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).
  48. 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).
  49. 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).
  50. 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).
  51. 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).
  52. 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).