Electronic properties of GaxIn1-xP ternary alloy from first-principles

摘要

The electronic properties of GaxIn1-xP ternary semiconductor alloy are investigated from first-principles. Calculation were performed using supercell (SC) approach in the framework of density functional theory (DFT). We use Tran-Blaha's modified Becke-Johnson (TB09) exchange potential together with correlation part of both the local density approximation (LDA) and M06 of Minnesota functionals. For the SC calculations, the band structures were unfolded, and the effective band structures were used to obtain the composition dependence of the fundamental gap energy. Also electron effective masses at the conduction band minima and hole effective masses at the Gamma point as functions of concentration x are calculated and compared with experimental data. The results show that the supercell approach leads to good estimation of energy gaps and bowing parameters for both direct and indirect gaps. The results of SC calculations also show a transition from (Gamma-Gamma) direct gap to (Gamma - x) indirect gap at x = 0.66, which is in agreement with experiments. Furthermore, our results show that the combination of TB09 exchange and M06 correlation potential can be used to estimate more accurate band structure profile than the well-known TB09-LDA for GaP, InP and their alloys. (C) 2016 Elsevier B.V. All rights reserved.