• 文献标题:   Dynamical conductivity of gated AA-stacking multilayer graphene with spin-orbital coupling
  • 文献类型:   Article
  • 作  者:   CHANG CP
  • 作者关键词:  
  • 出版物名称:   RSC ADVANCES
  • ISSN:  
  • 通讯作者地址:   Tainan Univ Technol
  • 被引频次:   0
  • DOI:   10.1039/c4ra17088a
  • 出版年:   2015

▎ 摘  要

An efficient method, without the numerical diagonalization of a huge Hamiltonian matrix and calculation of a tedious Green's function, is proposed to calculate the exact energy spectrum and dynamical conductivity in gated AA-stacking N-layer graphene (AANLG) with intrinsic spin-orbital coupling (SOC). The 2N x 2N tight-binding Hamiltonian matrix, velocity operator and Green's function representation of AANLG are simultaneously reduced to N 2 x 2 diagonal block matrices through a proper transformation matrix. Gated AANLG with intrinsic SOC is reduced to N graphene-like layers. The energy spectrum of a graphene-like layer is E = epsilon(perpendicular to) +/- epsilon(parallel to), and epsilon(perpendicular to) depends on the interlayer interaction, gated voltage and layer number. epsilon(parallel to) = root E-MG(2) vertical bar Delta(2) , where E-MG is the energy spectrum of a graphene monolayer and Delta is the magnitude of the intrinsic SOC. More importantly, by inserting the diagonal block velocity operator and Green's function representation in the Kubo formula, the exact dynamical conductivity of AANLG is shown to be sigma = Sigma(N)(j=i) sigma(j), the sum of the dynamical conductivity of N graphene-like layers. The analytical form of sigma(j) is presented and the dependence of sigma(j) on epsilon(perpendicular to), Delta, and chemical potential is clearly demonstrated. Moreover, the effect of the Rashba SOC on the electronic properties of AANLG is explored with the exact energy spectrum presented.