Optoelectronic and dielectric properties of GaAsxSb1-x ternary alloys

Based on the pseudopotential scheme under the virtual crystal approximation in which the effect of compositional disorder is involved, the dependence of optoelectronic properties of GaAsxSb1-x on alloy composition x have been studied. Our results showed generally good agreement with the available experimental data. The material of interest is found to exhibit features of both direct and indirect band-gap semiconductor depending on the alloy composition x. The method used has been combined with the Harrison bond-orbital model and employed to calculate the dielectric constants and their composition dependence.