Ab initio Study of the Electronic Structure of GaAs Nanotubes

Structural and electronic properties of single-walled GaAs nanotubes with diameter from 0.5 nm to 5 nmhave investigated based on density functional theory using the Local Density Approximation (LDA). We have studiedthe variation of radial distribution, buckling, total energy, density of states and band gap of GaAsNTs as functions oftube diameter. Our results revealed that there is a correlation between band gap and buckling: the higher buckling, thelower band gap and the buckling separation increase as the tube diameter decreases. Band structure calculations showthat all zigzag GaAsNTs except of small diameter (4, 0) have a direct gap. The indirect band gap of (4,0) GaAsNT canstem from band sequence change induced by curvature effect of the narrow diameter and the formation of benign bucklingseparations. Our results show that the π–π hybridization effect and the formation of benign buckling separations play akey role in the band sequence changes of (4,0) tube.

کلیدواژه ها:

GaAs nanotube ، Electronic structure ، DFT ، structural properties ، radial buckling