拓扑缺陷的不同分布对单壁碳纳米管电学性能的影响  

Electronic Properties of Single Carbon Nanotubes with Pentagon-heptagon Pairs Defects

作　　者：胡慧芳[1] 张丽芳[2] 汪小知[3] 梁君武[1] 

机构地区：[1]湖南大学应用物理系,湖南长沙410082 [2]中南大学物理科学与技术学院,湖南长沙410083 [3]中南大学信息科学与工程学院,湖南长沙410083

出　　处：《计算物理》2004年第3期369-372,共4页Chinese Journal of Computational Physics

基　　金：国家自然科学基金(50172063;50372018);湖南省自然科学基金(02JJY2013)资助项目

摘　　要：　在紧束缚近似基础上,利用扩展的Su Schriffer Heeger(SSH)模型,在实空间研究了在完整的"zigzag"碳纳米管中分别引入5 7,5 6 7,5 6 6 7拓扑缺陷所构成的(9,0) (8,0),(9,0) (7,0)和(9,0) (6,0)三种异质结的电学性能.通过研究表明:这些拓扑缺陷不仅改变碳管的直径,而且支配费米能级附近的电学行为.并计算了(9,0) (8,0),(9,0) (7,0)和(9,0) (6,0)系统的电子态密度,对这3种异质结的能带结构和电子态密度进行了比较.结果表明:五边形和七边形在碳管中分布的不同对碳管电学性能的影响明显不同.因此,可以研制出基于这些异质结的不同的电子器件基元.Using the extended Su-Schriffer-Heeger model, in the real space it investigated the features of energetics, the electronic properties of carbon nanotubes, containing pentagon-heptagon pairs (5/7), pentagon-hexagonal-heptagon (5/6/7) and pentagon-hexagonal-hexagonal-heptagon (5/6/6/7) topological defects in the perfect hexagonal network of the zigzag configuration. The present calculations show that the pentagon-heptagon pair defects on the nanotube structure are not only responsible for a change in nanotube diameter, but also govern the electronic behavior around Fermi level. By calculating the densities of states of the (9,0)-(8,0), (9,0)-(7,0) and (9,0)-(6,0) system, and the densities and band of these heterojunctions have been compared. These results show that the different arranges of pentagon and heptagon along the axis have obvious difference on electrical properties of carbon Nanotube. So different electronic devices based on these heterojunctions can be created.

关 键 词：碳纳米管 分子结 异质结 拓扑缺陷 电子态密度 

分 类 号：TB383[一般工业技术—材料科学与工程]