Improved tight-binding parameters of III–V semiconductor alloys and their application to type-II superlattices

Abstract

Abstract A simple tight-binding method for ternary semiconductor alloys is generalized to calculate the properties of the semiconductor alloys accurately. Specifically independently adjustable parameters, which represent compositional disorder, are incorporated in all the ternary tight-binding parameters. Energy levels and effective masses agree well with the reference values only by the proposed method. We have applied the method to calculate the band gaps and a spectrum of the absorption coefficient of (InAs)/(Ga x In1−x Sb) type-II superlattices. The calculated band-gaps agree well with the experimental ones and we could well reproduce the shape of the absorption coefficient spectrum calculated by an empirical pseudopotential scheme.