Kouji SEGAWA
Associate Professor, Institute of Scientific and Industrial Research (ISIR), Osaka University- Field of Specialty：
- Condensed matter physics
- Topics of Research：
- (C01) Novel Phenomena in Electron Fluids with Broken Inversion Symmetry
- Specific Topics：
- Topological insulator, topological superconductor
■ Laboratory Website
RESEARCH
My main research topic was studying the high-Tc cuprates, in particular, such as physical properties of YBa2Cu3Oy (YBCO) and related systems. I have succeeded in detwinning slightly-doped YBCO and found an in-plane anisotropy originated from a possible nematicity of electrons. Another outstanding achievement was doping n-type carriers to YBCO by La-substitution for Ba.
In the present research program, I am studying topological insulators and topological superconductivity by using experimental techniques. Our high-quality crystals have been producing interesting results, but I will also study a junction between the topological insulator and another material, and search for a new superconductor based on topologically non-trivial materials.
EDUCATION
- 1994
- Bachelor of Science (Physics), Kyoto University
- 1996
- Master of Science (Physics), University of Tokyo
- 2005
- Ph.D. (Science), University of Tokyo
PROFESSIONAL EXPERIENCE
- 1996-2001
- Research Associate, CRIEPI
- 2001-2007
- Research Scientist, CRIEPI
- 2007-2008
- Assistant Professor, ISIR, Osaka University
- 2008-Present
- Associate Professor, ISIR, Osaka University
SELECTION OF PUBLICATIONS
"Direct Measurement of the Out-of-Plane Spin Texture in the Dirac-Cone Surface State of a Topological Insulator",
S. Souma, K. Kosaka, T. Sato, M. Komatsu, A. Takayama, T. Takahashi, M. Kriener, K. Segawa and Y. Ando,
Phys. Rev. Lett., 106 (2011) 216803.
"Bulk Superconducting Phase with a Full Energy Gap in the Doped Topological Insulator CuxBi2Se3",
M. Kriener, K. Segawa, Z. Ren, S. Sasaki and Y. Ando,
Phys. Rev. Lett., 106 (2011) 127004.
"Direct Evidence for the Dirac-Cone Topological Surface States in the Ternary Chalcogenide TlBiSe2",
T. Sato, K. Segawa, H. Guo, K. Sugawara, S. Souma, T. Takahashi and Y. Ando,
Phys. Rev. Lett., 105 (2010) 136802.
"Zero-doping state and electron-hole asymmetry in an ambipolar cuprate",
Kouji Segawa, M. Kofu, S-H. Lee, I. Tsukada, H. Hiraka, M. Fujita, S. Chang, K. Yamada, and Yoichi Ando,
Nature Physics 6 (2010) 579-583.
"Doping n-Type Carriers by La-Substitution for Ba in YBa2Cu3Oy System",
K. Segawa and Y. Ando,
Phys. Rev. B, 74 (2006) 100508.
"Intrinsic Hall response of the CuO2 planes in a chain-plane-composite system of YBa2Cu3Oy",
K. Segawa and Y. Ando,
Phys. Rev. B, 69 (2004) 104521.
"Electrical resistivity anisotropy from self-organized one-dimensionality in high-temperature superconductors",
Yoichi Ando, Kouji Segawa, Seiki Komiya, and A. N. Lavrov,
Phys. Rev. Lett. 88 (2002) 137005.
