• 文献标题:   Magnetic Kronig-Penney-type graphene superlattices: finite energy Dirac points with anisotropic velocity renormalization
  • 文献类型:   Article
  • 作  者:   LE VQ, PHAM CH, NGUYEN VL
  • 作者关键词:  
  • 出版物名称:   JOURNAL OF PHYSICSCONDENSED MATTER
  • ISSN:   0953-8984 EI 1361-648X
  • 通讯作者地址:   VAST
  • 被引频次:   14
  • DOI:   10.1088/0953-8984/24/34/345502
  • 出版年:   2012

▎ 摘  要

We study the energy band structure of magnetic graphene superlattices with delta-function magnetic barriers and zero average magnetic field. The dispersion relation obtained using the T-matrix approach shows the emergence of an infinite number of Dirac-like points at finite energies, while the original Dirac point is still located at the same place as that for pristine graphene. The carrier group velocity at the original Dirac point is isotropically renormalized, but at finite energy Dirac points it is generally anisotropic. An asymmetry in the width between the wells and the barriers of the periodic potential induces a shift of the original Dirac point in the zero-energy plane, keeping the velocity renormalization isotropic.