中文摘要：

运用第一性原理的密度泛函理论,结合非平衡格林函数,研究了氮原子取代掺杂手性单壁（6,3）碳纳米管的电子结构和输运特性.计算结果表明：不同构形和不同数目的氮原子取代掺杂对手性碳管的输运性质有很复杂的影响.研究发现,氮原子掺杂明显改变了碳管的电子结构,使金属型手性碳管的输运性能降低,电流-电压曲线呈非线性变化,而且输运性能随着杂质原子间间距的变化而发生显著改变.在一定条件下,金属型碳管向半导体型转变.

英文摘要：

Using density functional theory and nonequilibrium Green＇s function,the electronic structure and transport properties of chiral （6,3） single-walled carbon nanotubes substituted by nitrogen atoms were investigated. The results show that the configurations and the concentration of the doped atoms have complicated effects on the transport properties of the chiral single-walled carbon nanotubes. The electronic structures of the carbon nanotubes are changed obviously. The transportation properties are degraded by the doping of nitrogen atoms and change significantly with the positions of impurity atoms in the structure. The currents-voltage curve shows nonlinear variation. Under certain conditions the metallic single-walled carbon nanotubes may be converted into semiconductors.