• 文献标题:   Universal quantized spin-Hall conductance fluctuation in graphene
  • 文献类型:   Article
  • 作  者:   QIAO ZH, WANG J, WEI YD, GUO H
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW LETTERS
  • ISSN:   0031-9007 EI 1079-7114
  • 通讯作者地址:   Univ Hong Kong
  • 被引频次:   22
  • DOI:   10.1103/PhysRevLett.101.016804
  • 出版年:   2008

▎ 摘  要

We report theoretical investigations of the quantized spin-Hall conductance fluctuation of graphene in the presence of disorder. Two graphene models that exhibit the quantized spin-Hall effect (QSHE) are analyzed. Model I is with unitary symmetry under an external magnetic field B not equal 0 but with a zero spin-orbit interaction, t(SO)=0. Model II is with symplectic symmetry where B=0 but t(SO)not equal 0. The two models give exactly the same universal QSHE conductance fluctuation value 0.285 +/- 0.005e/4 pi regardless of symmetry. We also examined a third model that exhibits QSHE but with quadratic dispersion and obtained the same results. Finally, all three models of QSHE have a one-sided log-normal distribution for spin-Hall conductance. Our results strongly suggest that the quantized spin-Hall conductance fluctuation belongs to a new universality class.