多空位缺陷和硼氮杂质对锯齿型石墨烯纳米带电子结构的影响

肖建田¹，胡大胜²，陈灵娜^{1, 3}，吴取劲¹，李丽华 ¹

(1. 南华大学 计算机科学与技术学院，湖南 衡阳，421001；
2. 长沙师范学校，湖南 长沙，410100；
3. 中南大学 信息科学与工程学院，湖南 长沙，410083)

摘 要：利用基于密度泛函理论的第一性原理方法，研究多空位缺陷和掺杂对对称性锯齿型石墨烯纳米带(ZGNRs)的电子结构的影响。研究结果表明，具有相同位置的多空位缺陷或氮掺杂的对称性ZGNR 显示了半金属特性，而硼掺杂的对称性ZGNR显示了半导体性质。石墨烯纳米带的锯齿形边缘上和空位缺陷处都存在自旋极化的电子态，并且边缘上电子自旋呈反铁磁性排列。具有多空位缺陷的ZGNR磁矩依赖于带宽、空位缺陷的构型以及空位缺陷与边缘的距离，从而磁矩随着带宽的增加呈现震荡效应。这种特殊的缺陷和掺杂效应可用来设计新颖的自旋电子器件。

关键词：锯齿型石墨烯纳米带；缺陷；掺杂；电子结构

Effect of defect and boron/nitrogen doping on electronic properties of zigzag graphene nanoribbons

XIAO Jian-tian¹, HA Da-sheng², CHEN Ling-na^{1, 3}, WU Qu-jin¹, LI Li-hua¹

(1. School of Computer Science and Technology, University of South China, Hengyang 421001, China;
2. Changsha Normal College, Changsha 410100, China;
3. School of Information Science and Engineering, Central South University, Changsha 410083, China)

Abstract:Using first-principles based on density functional theory, the effect of multivacancies defect and boron/nitrogen doping on the eletronic properties of zigzag graphene nanoribbons (ZGNRs) was studied. The results show that symmetry ZGNRs with multivacancies defect or nitrogen doping at the same positions have the half-metallic behavior, but boron doping induces the semiconductor properties. The ground state of ZGNRs has an antiferromagnetic (AF) configuration, where electronic states with opposite spins are highly localized at the edges of ZGNRs and multivacancies. The magnetism property of ZGNRs with multivacancies defect depends on the ribbon width, the defect configuration, and the distance between the defect and the ribbon edge. The magneticmomentum is oscillatory with the increase of the ribbon.These unconventional defect and doping effects could be used to design novel spin nanoelectronic devices.

Key words:zigzag graphene nanoribbons; defect; doping; electronic property