Abstract: Based on energy dispersion relation of the single-walled carbon nanotubes (SWCNTs), the electronic velocity and effective mass of the lowest conduction band for the SWCNTs were computed, and the relation of the electronic velocity and effective mass with the wave vector and diameters of the SWCNTs were discussed emphatically. The calculated results show that the electronic velocity and effective mass significantly depend on the structure parameter of the semiconducting zigzag-SWCNTs such as their diameter. The electronic velocity and effective mass of the lowest conduction band for various armchair (always metallic) SWCNTs and metallic zigzag-SWCNTs have the same changing curves versus the wave vector, but for various semiconducting zigzag-SWCNTs the electronic velocity and effective mass of the lowest conduction band have different changing curves versus the wave vector. This means that under the low bias voltage, various metallic zigzag-SWCNTs and armchair SWCNTS with different diameters have the same transport properties, while the semiconducting zigzag-SWCNTs with different diameters have different transport properties.

Key words: Carbon nanotube, Energy dispersion relation, The lowest conduction band, Electronic velocity, Effective mass