石墨烯纳米带电极区N掺杂电子输运性质研究  

Electron transport properties of N-doped graphene nanoribbons in electrode region

作　　者：卜习习 苗瑞霞 郭三栋 叶海安 邵奇 BU Xi-Xi;MIAO Rui-Xia;GUO San-Dong;YE Hai-An;SHAO Qi(School of Electronic Engineering,Xi’an University of Posts and Telecommunications,Xi’an 710121,China)

机构地区：[1]西安邮电大学电子工程学院,西安710121

出　　处：《原子与分子物理学报》2021年第1期52-56,共5页Journal of Atomic and Molecular Physics

基　　金：国家自然科学基金(51302215);陕西省自然科学基金(2018JQ6084)。

摘　　要：运用密度泛函理论和非平衡格林函数结合的方法,研究电极区N掺杂对扶手椅型石墨烯纳米带电子输运特性的影响.结果表明,与本征扶手椅型石墨烯纳米带电流-电压曲线相比,宽度为7的石墨烯纳米带电流-电压曲线表现出明显的不对称性,其中心N掺杂表现强烈的整流特性,整流系数达到10^(2)数量级,且将N原子从电极区中心位置移动到边缘,整流特性减弱.研究结果表明宽度为7的扶手椅型石墨烯纳米带出现强整流现象的原因主要是负向偏压下能量窗内没有透射峰引起的,该研究结果对将来石墨烯整流器件的设计具有重要的意义.The electronic transport properties of N-doped armchair graphene nanoribbons in the electrode region are investigated using density functional theory with non-equilibrium Green’s function in which a N dopant is considered to substitute the center or edge carbon atom of one electrode based on armchair graphene nanoribbons with the width of 7. The results of simulation shown that the current-voltage curves of the width of 7 exhibit obvious asymmetry comparing with intrinsic armchair graphene nanoribbons. When a nitrogen atom doping in the center of the width of 7 device,the maximum rectification ratio can reach 10^(2). As the impurity atom moves to the edge from center position,the observed rectification decreases. The results indicate that the asymmetric doping with different positions of the impurity atom influences the electron transport of the device and plays an important role for the future design of graphene rectifiers.

关 键 词：电子输运 整流现象 非平衡格林函数方法 石墨烯纳米带 

分 类 号：O472[理学—半导体物理]