含有五元环-七元环缺陷的单壁纳米碳管的能带结构分析

Energy band analysis of SWNTs with 5-7 element loop defects

运用第一性原理的计算方法结合非平衡格林函数(NEGF)和密度泛函理论(DFT)计算带有五元环-七元环拓扑缺陷对的单壁纳米碳管(SWNTs)的输运性质,同时计算(7,0)-(8,0)和(8,0)-(9,0)两种不同类型的纳米碳管异质结的能带结构并比较其与理想(7,0)、(8,0)、(9,0)碳管的不同.结果表明:五元环-七元环拓扑缺陷对碳管在费米能级附近的输运特性有着很大的影响;不同类型的碳管的连接方式对碳管输运性质的影响也有明显的差异.

The computation method of first principle as well as non-equilibrium Green function（NEGF） and density functional theory（DFT） were used to determine the transmission property of single walled carbon nanotubes with 5-7 element loop defects. As a result, the energy band structures of the （7,0）-（8,0） and （8,0）-（9,0） SWNTs＇ heterojunctions were calculated and compared to those of ideal （7,0）, （8,0）, （9,0） SWNTs. The result showed that the 5-7 element loop topological defect had great influence on the transmission characteristics of the carbon tubes near the nanometer energy level; and different junction mode could evidently affect the difference in transmission property of electrons.