Anisotropic Intervalley Plasmon Excitations in Graphene  

作　　者：陈健 许怀哲 

机构地区：[1]State Key Laboratory of Software Development Environment and Department of Physics,Beihang University

出　　处：《Communications in Theoretical Physics》2015年第4期520-524,共5页理论物理通讯（英文版）

基　　金：Supported by the National Basic Research Program of China(973 Program)under Grant No.2013CB934001;the State Key Laboratory of Software Development Environment under Grant No.SKLSDE-2013ZX-28

摘　　要：We investigate theoretically the intervalley plasmon excitations(IPEs) in graphene monolayer within the random-phase approximation. We derive an analytical expression of the real part of the dielectric function. We find a lowenergy plasmon mode with a linear anisotropic dispersion which depends on the Fermi energy and the dielectric constant of substrate. The IPEs show strongly anisotropic behavior, which becomes significant around the zigzag crystallographic direction. More interestingly, the group velocity of IPE varies from negative to positive, and vanishes at special energy.

关 键 词：PLASMON intervalley ANISOTROPY GRAPHENE 

分 类 号：O53[理学—等离子体物理] O343.8[理学—物理]