Electronic and transport properties of (6,2) carbon and silicon nanotubes: A first-principles calculation

Abstract

Abstract The aim of this study is to provide a detailed analysis on the electronic and transport properties of (6,2) carbon and silicon nanotubes attached to metallic gold nanosheets electrodes by density functional theory (DFT) and the Non-Equilibrium Green's Function (NEGF) methods. It is revealed that (6,2) carbon nanotube has an indirect band gap, 0.25 eV, whereas a (6,2) silicon nanotube shows metallic behavior. Additionally, the effects of the temperature on the quantum transport of the CNT and SiNT are also investigated. The current-voltage (I–V) characteristics indicate the higher value of the current in (6,2) SiNT in comparison with that of (6,2) CNT. Moreover, the current in low temperature is less than that of high temperature and a negative differential resistance (NDR) phenomenon is observed. The results imply a temperature independent transport properties in a single SiNT. As the number of carbon nanotubes, connected in series, increases, a significant increase in the current of the system is observed.