セガワ コウジ   SEGAWA KOJI
  瀬川 耕司
   所属   京都産業大学  理学部 物理科学科
   職種   教授
言語種別 英語
発行・発表の年月 2011/05
形態種別 研究論文
標題 Direct Measurement of the Out-of-Plane Spin Texture in the Dirac-Cone Surface State of a Topological Insulator
執筆形態 その他
掲載誌名 PHYSICAL REVIEW LETTERS
出版社・発行元 AMER PHYSICAL SOC
巻・号・頁 106(21)
著者・共著者 S. Souma,K. Kosaka,T. Sato,M. Komatsu,A. Takayama,T. Takahashi,M. Kriener,Kouji Segawa,Yoichi Ando
概要 We have performed spin-and angle-resolved photoemission spectroscopy of Bi2Te3 and present the first direct evidence for the existence of the out-of-plane spin component on the surface state of a topological insulator. We found that the magnitude of the out-of-plane spin polarization on a hexagonally deformed Fermi surface of Bi2Te3 reaches maximally 25% of the in-plane counterpart, while such a sizable out-of-plane spin component does not exist in the more circular Fermi surface of TlBiSe2, indicating that the hexagonal deformation of the Fermi surface is responsible for the deviation from the ideal helical spin texture. The observed out-of-plane polarization is much smaller than that expected from the existing theory, suggesting that an additional ingredient is necessary for correctly understanding the surface spin polarization in Bi2Te3.
DOI 10.1103/PhysRevLett.106.216803
ISSN 0031-9007/1079-7114
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