Electronic structures of carbon nanotubes studied by Green function theory

为了探讨掺杂碳纳米管在半导体器件中的应用和超导电性的可能性，对掺杂碳纳米管的电子结构进行了系统的研究。我们讨论了掺杂硼或氮的纳米管的杂质水平，掺杂率对电子结构的依赖性，以及三维性对多壁纳米管的影响。此外，为了讨论详细的物理性质，我们发展了基于密度泛函理论的绿色函数方法。

Electronic structures of impurity-doped carbon nanotubes were studied systematically in order to discuss the application to semiconductor device and the possibility of superconductivity. We discussed impurity levels of boron- or nitrogen-doped nanotubes, the doping rate dependence of the electronic structures, and the effect of three-dimensionality in multi-walled nanotubes. Furthermore, to discuss the detailed physical properties, we developed the method using Green function theory based on the density functional theory.