C/SiC纳米管异质结电子结构的第一性原理研究

First principles study of electronic properties of carbon/silicon carbide nanotube heterojunction

采用基于密度泛函理论的第一性原理计算,对扶手椅型(4,4)和(6,6)及锯齿型(8,0)和(10,0)C/SiC纳米管异质结的电子结构进行了研究.结果表明两类异质结结构都表现为半导体特性.扶手椅型纳米管异质结形成了Ⅰ型异质结,电子和空穴都限制在碳纳米管部分.锯齿型纳米管异质结中价带顶主要分布在碳纳米管部分及C/SiC界面处,而导带底均匀分布在整个纳米管异质结上.这两种异质结结构在未来纳米器件中具有潜在的应用价值.

Using the first-principles method,the electronic properties of the armchair and the zigzag C/SiC nanotube heterojunctions are investigated.Both heterjunctions exhibit semiconducting behaviors with a direct energy band.For the armchair heterojunction,type I heterojection is formed at the interface between the C and the SiC nanotubes,and the electrons and holes are confined in the C nanotube part.In the zigzag heterojunction,the electrons are localized in the C nanotube part,whereas the holes are distributd in the heterojunction uniformly.These heterojunctions can be good candidates for the future nano-devices.