About NSRRC / Staff Directory

Condensed Matter Physics Group


Name: 岡本淳( Jun Okamoto )
EXT.: 7132
E-mail: okamoto.jun@nsrrc.org.tw
Education:
  • 2000.4-2001.3 Postgraduate research student, Department of Physics, University of Tokyo, Japan
  • 1997.4-2000.3 Ph. D. in Physics, University of Tokyo, Japan
  • 1995.4-1997.3 M. S. in Physics, University of Tokyo, Japan
  • 1993.3-1995.3 B. S. in Physics, University of Tokyo, Japan
Experience:
  • Since 2014.2 Research assistant scientist, National Synchrotron Radiation Research Center, Taiwan R. O. C.
  • 2009.4-2014.2 Research assistant professor, Condensed Matter Research Center, Institute of Materials Structure Science, High Energy Accelerator Research Organization, Japan
  • 2004.4-2009.3 Project associate scientist, National Synchrotron Radiation Research Center, Taiwan
  • 2001.4-2004.3 Postdoctoral fellow, Synchrotron Radiation Research Center at SPring-8, Japan Atomic Energy Institute, Japan
Endstation:
  • BL5EPU (TLS)
Research Interests:
  • Strongly correlated electron systems
  • Magnetic materials
  • Multiferroics
  • Solid state physics
Selected Publications:
  • Antiferromagnetic Order of the Co2+ High-Spin State with a Large Orbital Angular Momentum in La1.5Ca0.5CoO4
    J. Okamoto, H. Nakao, Y. Yamasaki, H. Wadati, A. Tanaka, M. Kubota, K. Horigane, Y. Murakami, K. Yamada
    J. Phys. Soc. Jpn. 83 044705 (2014). DOI: 10.7566/JPSJ.83.044705
  • Pseudogap-related charge dynamics in the layered nickelate R2-xSrxNiO4 (x ~ 1)
    M. Uchida, Y. Yamasaki, Y. Kaneko, K. Ishizaka, J. Okamoto, H. Nakao, Y. Murakami, and Y. Tokura,
    Phys. Rev. B 86, 165126 (2012).         DOI: 10.1103/PhysRebB.86.165126
  • High-temperature thermoelectric properties of the double-perovskite ruthenium
    oxide (Sr1-xLax)2ErRuO6,
    R. Takahashi, R. Okazaki, Y. Yasui, I. Terasaki, T. Sudayama, H. Nakao, Y. Yamasaki,
    J. Okamoto, Y. Murakami, and Y. Kitajima,
    J. Appl. Phys. 112, 073714 (2012).      DOI: 10.1063/1.4757632
  • Origin of the Large Polarization in Multiferroic YMnO3 Thin Films Revealed by Soft- and Hard-X-Ray Diffraction, H. Wadati, J. Okamoto, M. Garganourakis, V. Scagnoli, U. Staub, Y. Yamasaki, H. Nakao, Y. Murakami, M. Mochizuki, M. Nakamura, M. Kawasaki, and Y. Tokura, Phys. Rev. Lett. 108, 047203 (2012).   DOI: 10.1103/PhysRevLett.108.047203
  • Resonant elastic soft X-ray scattering in oxygen-ordered YBa2Cu3O6+d
    D. G. Hawthorn, K. M. Shen, J. Geck, D. C. Peets, H. Wadati, J. Okamoto, S.-W. Huang, D. J. Huang, H.-J. Lin, J. D. Denlinger, R. Liang, D. A. Bonn, W. N. Hardy, and G. A. Sawatzky,
    Phys. Rev. B 84, 075125 (2011).         DOI: 10.1103/PhysRevB.84.075125
  • Quasi-two-dimensional d-spin and p-hole ordering in the three-dimensional perovskite La1/3Sr2/3FeO3
    J. Okamoto, D. J. Huang, K. S. Chao, S. W. Huang, C.-H. Hsu, A. Fujimori, A. Masuno, T. Terashima, M. Takano, and C. T. Chen
    Phys. Rev. B 82, 132402 (2010).         DOI: 10.1103/PhysRevB.82.132402
  • Multiferroic nanoregions and a memory effect in cupric oxide
    W. B. Wu, D. J. Huang, J. Okamoto, S. W. Huang, Y. Sekio, T. Kimura, and C. T. Chen,
    Phys. Rev. B 81, 172409 (2010).         DOI: 10.1103/PhysRevB.81.172409
  • Thermally or Magnetically Induced Polarization Reversal in the Multiferroic CoCr2O4
    Y. J. Choi, J. Okamoto, D. J. Huang, K. S. Chao, H. J. Lin, C. T. Chen, M. van Veenendaal, T. A. Kaplan, and S-W. Cheong,
    Phys. Rev. Lett. 102, 067601 (2009).DOI: 10.1103/PhysRevLett.102.067601
  • Magnetic Ground State and Transition of a Quantum Multiferroic LiCu2O2
    S. W. Huang, D. J. Huang, J. Okamoto, C. Y. Mou, W. B. Wu, K. W. Yeh, C. L. Chen, M. K. Wu, H. C. Hsu, F. C. Chou, and C. T. Chen,
    Phys. Rev. Lett. 101, 077205 (2008).DOI: 10.1103/PhysRevLett.101.077205
  • Nature of Magnetic Coupling between Mn Ions in As-Grown Ga1-xMnxAs
    Studied by X-Ray Magnetic Circular Dichroism
    Y. Takeda, M. Kobayashi, T. Okane, T. Ohkochi, J. Okamoto, Y. Saitoh, K. Kobayashi, H.Yamagami, A. Fujimori, A. Tanaka, J. Okabayashi, M. Oshima, S. Ohya, P. N. Hai, and M. Tanaka,     
    Phys. Rev. Lett. 100, 247202 (2008). DOI: 10.1103/PhysRevLett.100.247202
  • S. W. Huang, D. J. Huang, J. Okamoto, W. B. Wu, C. T. Chen, K. W. Yeh, C. L. Chen, M. K. Wu, H. C. Hsu, and F. C. Chou,
  • Magnetic order of LiCu2O2 studied by resonant soft x-ray magnetic scattering
  • Solid State Comm. 147, 234 (2008).   DOI: 10.1016/j.ssc.2008.04.04
  • Soft X-ray Magnetic Circular Dichroism Study of Uranium Monochalcogenides
    at Uranium N4,5 Absorption Edges
    T. Okane, Y. Takeda, J. Okamoto, K. Mamiya, T. Ohkochi, S.-I. Fujimori, Y. Saitoh, H. Yamagami, A. Fujimori, A. Ochiai, and A. Tanaka,
    J. Phys. Soc. Jpn. 77, 024706 (2008). DOI: 10.1143/JPSJ.77.024706
  • J. Okamoto, T. Okane, Y. Saitoh, K. Terai, S.-I. Fujimori, Y. Muramatsu, K. Yoshii, K. Mamiya, T. Koide, A. Fujimori, Z. Fang, Y. Takeda, and M. Takano,
  • Soft x-ray magnetic circular dichroism study of Ca1-xSrxRuO3 across the ferromagnetic quantum phase transition
  • Phys. Rev. B 76, 184441 (2007).         DOI: 10.1103/PhysRevB.76.184441
  • Symmetry of Multiferroicity in a Frustrated Magnet TbMn2O5
    J. Okamoto, D. J. Huang, C.-Y. Mou, K. S. Chao, H.-J. Lin, S. Park, S-W. Cheong, and C. T. Chen,
    Phys. Rev. Lett. 98, 157202 (2007).     DOI: 10.1103/PhysRevLett.98.157202
  • Soft X-Ray Magnetic Circular Dichroism Study of Weakly Ferromagnetic
    Zn1-xVxO Thin Film
    Y. Ishida, J. I. Hwang, M. Kobayashi, Y. Takeda, K. Mamiya, J. Okamoto, S.-I. Fujimori, T. Okane, K. Terai, Y. Saitoh, Y. Muramatsu, A. Fujimori, A. Tanaka, H. Saeki, T. Kawai, and H. Tabata
    Appl. Phys. Lett. 90, 022510 (2007).   DOI: 10.1063/1.2431571
  • Bandwidth-Control Metal-Insulator Transitions in Pyrochlore-type Ru Oxides
    J. Okamoto, S. -I. Fujimori, T. Okane, A. Fujimori, M. Abbate, S. Yoshii, and M. Sato,
  • Evolution of the Electronic Structure Across the Filling-Control and
  • Phys. Rev. B 73, 035127 (2006). DOI: 10.1103/PhysRevB.73.035127
  • Charge-Orbital Ordering and Verwey Transition in Magnetite Measured by Resonant Soft X-Ray Scattering
    D. J. Huang, H.-J. Lin, J. Okamoto, K. S. Chao, H.-T. Jeng, G. Y. Guo, C.-H. Hsu, C.-M. Huang, D. C. Ling, W. B. Wu, C. S. Yang, and C. T. Chen,
    Phys. Rev. Lett. 96, 096401 (2006).     DOI: 10.1103/PhysRevLett.96.096401
  • Soft X-ray Absorption Magnetic Circular Dichroism Study of Ferromagnetic
    Superconductor UGe2
    T. Okane, J. Okamoto, K. Mamiya, S.-I. Fujimori, Y. Takeda, Y. Saitoh, Y. Muramatsu, A. Fujimori, Y. Haga, E. Yamamoto, A. Tanaka, T. Honma, Y. Inada, and Y. Ōnuki,
    J. Phys. Soc. Jpn. 75, 024704 (2006). DOI: 10.1143/JPSJ.75.024704
  • SrFe1-xCoxO3: Magnetic circular x-ray dochroism study
    J. Okamoto, K. Mamiya, S. –I. Fujimori, T. Okane, Y. Saitoh, Y. Muramatsu, K. Yoshii, A. Fujimori, A. Tanaka, M. Abbate, T. Koide, S. Ishiwata, S. Kawasaki, and M. Takano,
  • Antiferromagnetic-to-ferromangetic transition induced by diluted Co in
  • Phys. Rev. B 71, 104401 (2005).         DOI: 10.1103/PhysRevB.71.104401
  • Orbital Symmetry and Electron Correlation in NaxCoO2
    W. B. Wu, D. J. Huang, J. Okamoto, A. Tanaka, H.-J. Lin, F. C. Chou, A. Fujimori, and C. T. Chen,
    Phys. Rev. Lett. 94, 146402 (2005).     DOI: 10.1103/PhysRevLett.94.146402
  • Characterization of magnetic components in the diluted magneticsemiconductor Zn1-xCoxO
    by x-ray magnetic circular dichroism
    M. Kobayashi, Y. Ishida, J. l. Hwang, T. Mizokawa, A. Fujimori, K. Mamiya, J. Okamoto, Y. Takeda, T. Okane, Y. Saitoh, Y. Muramatsu, A. Tanaka, H. Saeki, H. Tabata, and T. Kawai,
    Phys. Rev. B 72, 201201 (2005).       DOI: 10.1103/PhysRevB.72.201201
  • High energy spectroscopic study of the III-V nitride-based diluted magnetic semiconductor Ga1-xMnxN
    J. I. Hwang, Y. Ishida, M. Kobayashi, H. Hirata, K. Takubo, T. Mizokawa, A. Fujimori, J. Okamoto, K. Mamiya, Y. Saito, Y. Muramatsu, H. Ott, A. Tanaka, T. Kondo, and H. Munekata,
    Phys. Rev. B 72, 085216 (2005).        DOI: 10.1103/PhysRevB.72.08521
  • Photoemission study of the electronic structure and the metal-semiconductor
    transition in the pyrochlore-type Tl2Ru2O7
    J. Okamoto, T. Mizokawa, A. Fujimori, T. Takeda, R. Kanno, F. Ishii, and T. Oguchi,
    Phys. Rev. B 69, 035115 (2004).         DOI: 10.1103/PhysRevB.69.035115
  • Nearly localized nature of f electrons in CeTIn5 (T=Rh,Ir), S. –I. Fujimori, T. Okane, J. Okamoto, K. Mamiya, Y. Muramatsu, A. Fujimori, H. Harima, D. Aoki, S. Ikeda, H. Shishido, Y. Tokiwa, Y. Haga, and Y. Ōnuki, Phys Rev. B 67, 144507 (2003).                DOI: 10.1103/PhysRevB.67.144507
  • X-Ray Absorption of the Negative Charge Transfer CMR Material SrFe1-xCoxO3
    M. Abbate, G. Zampieri, J. Okamoto, A. Fujimori, Y. Takeda, R. Kanno, S. Kawasaki, and M. Takano,
    Phys. Rev. B 65, 165120 (2002). DOI: 10.1103/PhysRevB.65.165120
  • Magnetic Circular Dichroism of X-ray Emission for Gadolinium in 4d-4f Excitation Region
    Y. Takayama, M. Shinoda, K. Obu, C. Lee, H. Shiozawa, M. Hirose, H. Ishii, T. Miyahara and J. Okamoto,
    J. Phys. Soc. Jpn. 71, 340 (2002).              DOI: 10.1143/JPSJ.71.340
  • Close Correlation between the Magnetic Moments, Lattice Distortions and Hybridization in LaMnO3 and La1-xSrxMnO3+ δ: Doping-Dependent Magnetic Circular X-Ray Dichroism Study T. Koide, H. Miyauchi, J. Okamoto, T. Shidara, T. Sekine, T. Saitoh, A. Fujimori, H. Fukutani, M. Takano and Y. Takeda, Phys. Rev. Lett. 87, 246404 (2001). DOI: 10.1103/PhysRevLett.87.246404
  • Direct Determination of Purely Interfacial Magnetic Moments and Ferromagnetism-to-Superparamagnetism Transition in Co Nanoclusters on Au(111) T. Koide, H. Miyauchi, J. Okamoto, T. Shidara, A. Fujimori, K. Amemiya, H. Takeshita, S. Yuasa, T. Katayama and Y. Suzuki, Phys. Rev. Lett. 87, 257201 (2001). DOI: 10.1103/PhysRevLett.87.257201
  • Magnetic circular x-ray dichroism study of La1-xSrxCoO3
    J. Okamoto, H. Miyauchi, T. Sekine, T. Shidara, T. Koide, K. Amemiya, A. Fujimori, T. Saitoh, A. Tanaka,Y. Takeda, and M. Takano,
    Phys. Rev. B 62, 4455 (2000).    DOI: 10.1103/PhysRevB.62.4455
  • Correlation effects in the electronic structure of SrRuO3
    J. Okamoto, T. Mizokawa, A. Fujimori, I. Hase, M. Nohara, H. Takagi, Y. Takeda, and M.Takano,
    Phys. Rev. B 60, 2281 (1999).    DOI: 10.1103/PhysRevB.60.2281
  • Hubbard splitting and electronic correlation in the ferromagnetic metal CrO2
    T. Tsujioka, T. Mizokawa, J. Okamoto, A. Fujimori, M. Nohara, H. Takagi, K. Yamaura, and M. Takano,
    Phys. Rev. B 56, R15509 (1997). DOI: 10.1103/PhysRevB.56.R15509
  • Electronic Structure of SrRuO3
    K. Fujioka, J. Okamoto, T. Mizokawa, A. Fujimori, I. Hase, M. Abbate, H. J. Lin C. T. Chen, Y. Takeda, and M. Takano,
    Phys. Rev. B 56, 6380 (1997).    DOI:10.1103/PhysRevB.56.6380