Electronic Structure of [100]-Oriented Free-Standing Semiconductor Nanowires

Abstract

We report on a theoretical study of the electronic structure of [100]-oriented free-standing III-V semiconductor nanowires with quadratic (square wire) and rectangular (nanobelt) cross-sections based on an atomistic tight-binding approach. It is shown that at the same cross-section aspect ratio, the characteristics of the band structure and state wave functions of the nanowires in the vicinity of the band edges are insensitive to variation of the lateral size, although the band energies show a strong dependence on the lateral size. It is also shown that the effective mass of the conduction bands of the nanowires is systematically enhanced with decrease of the nanowire size, and k(.)p analysis generally overestimates the effective mass enhancement.