Gap opening and tuning in single-layer graphene with combined electric and magnetic field modulation  

作　　者：林鑫 王海龙 潘晖 许怀哲 

机构地区：[1]Department of Physics,Beihang University

出　　处：《Chinese Physics B》2011年第4期446-455,共10页中国物理B（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant Nos. 60776067 and 10974011)

摘　　要：The energy band structure of single-layer graphene under one-dimensional electric and magnetic field modulation is theoretically investigated. The criterion for bandgap opening at the Dirac point is analytically derived with a two-fold degeneracy second-order perturbation method. It is shown that a direct or an indirect bandgap semiconductor could be realized in a single-layer graphene under some specific configurations of the electric and magnetic field arrangement. Due to the bandgap generated in the single-layer graphene, the Klein tunneling observed in pristine graphene is completely suppressed.The energy band structure of single-layer graphene under one-dimensional electric and magnetic field modulation is theoretically investigated. The criterion for bandgap opening at the Dirac point is analytically derived with a two-fold degeneracy second-order perturbation method. It is shown that a direct or an indirect bandgap semiconductor could be realized in a single-layer graphene under some specific configurations of the electric and magnetic field arrangement. Due to the bandgap generated in the single-layer graphene, the Klein tunneling observed in pristine graphene is completely suppressed.

关 键 词：gap opening at Dirac point single-layer graphene electric and magnetic superlattice second-order perturbation 

分 类 号：O481[理学—固体物理]