Anisotropic localization behavior of graphene in the presence of diagonal and off-diagonal disorders  

作　　者：王莉敏 拾邵聪 章维益 

机构地区：[1]The National Laboratory of Solid State Microstructures and the Department of Physics, Nanjing University

出　　处：《Chinese Physics B》2013年第12期416-421,共6页中国物理B（英文版）

基　　金：Project supported by the National Basic Research Program of China(Grant No.2010CB923404);the National Natural Science Foundation of China(Grant No.11021403);the National Science Fund for Distinguished Young Scholars of China(Grant No.10025419)

摘　　要：Anisotropic localization of Dirac fermions in graphene along both the x and y axes was studied using the transfer-matrix method. The two-parameter scaled behavior around the Dirac points was observed along the x axis with off-diagonal disorder. In contrast, the electronic state along the y axis with armchair edges was delocalized, which can be described well by single parameter scaling theory. This implies that the breakdown of the single-parameter scaling is related to the zigzag edge along the x axis. Furthermore, dimerization induced by the substrate suppresses the two-parameter scaling behavior along the x axis and preserves the delocalized state along the y axis. Our results also demonstrate anisotropic localization in graphene with diagonal disorder that can be tuned by dimerization.Anisotropic localization of Dirac fermions in graphene along both the x and y axes was studied using the transfer-matrix method. The two-parameter scaled behavior around the Dirac points was observed along the x axis with off-diagonal disorder. In contrast, the electronic state along the y axis with armchair edges was delocalized, which can be described well by single parameter scaling theory. This implies that the breakdown of the single-parameter scaling is related to the zigzag edge along the x axis. Furthermore, dimerization induced by the substrate suppresses the two-parameter scaling behavior along the x axis and preserves the delocalized state along the y axis. Our results also demonstrate anisotropic localization in graphene with diagonal disorder that can be tuned by dimerization.

关 键 词：anisotropic localization graphene dimerization 

分 类 号：O481[理学—固体物理]