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在紧束缚理论的基础上,推导出轴向拉伸和扭转形变时碳纳米管(CNT)的能带公式.结果显示拉伸和扭转形变都可以改变CNT的导电性质,在金属型和半导体型之间转变,特别是对于锯齿型CNT,根据n与3的余数关系,在拉伸和扭转中分别显示出三种不同的变化规律.进一步应用场效应晶体管Natori理论模拟计算形变对CNT场效应晶体管的电流-电压特性的影响,锯齿型CNT根据n与3的余数关系表现出不同的电流变化趋势,而对于扶手椅型CNT轴向拉伸不改变电流;在扭转形变时,CNT电流急剧升高,特别是扶手椅型CNT.锯齿型CNT和扶手椅型CNT的电流随扭转角度和外电压行为明显不同.在某些特定的扭转角度,电流随扭转角度变化非常显著,显示出锯齿型CNT和扶手椅型CNT发生半导体型与金属型之间的转变.
On the basis of the tight binding theory, the energy band formula of carbon nanotubes (CNTs) during axial tensile and torsional deformation was deduced. The results show that both tensile and torsional deformations can change the conductive properties of CNTs. In the metallic and semiconducting , Especially for zigzag type CNTs, three different variation rules are respectively shown in tensile and torsional modes according to the relation between the residuals of n and 3. Further application of field effect transistor Natori theory to simulate the effect of deformation on CNT field effect transistor , The zigzag CNT shows different current trend according to the relation between n and the remainder of 3, but does not change the current for the armchair type CNT axial stretching. When the twisting deformation, the CNT current increases sharply , Especially for armchair type CNTs.The current of serrated CNTs and armchair type CNTs varies significantly with the twist angle and the external voltage behavior.The change in current with twist angle is significant at some specific twist angles and shows that zigzag CNTs and The armchair type CNT undergoes a transition between a semiconductor type and a metal type.