First-principles Study of Structural, Electronic and Optical Properties of III-arsenide Binary GaAs and InAs, and III-Nitrides Binary GaN and InN: Improved Density-functional-theory Study

Abstract

We report results from first-principles density functional calculations using the full- potential linear augmented plane wave (FP-LAPW) method. For the exchange-correlation potential, local-density approximation (LDA) and generalized gradient approximation of Wu and Cohen (GGA-WC) have been used to calculate the structural, electronic properties of the zinc-blende GaAs, InAs, GaN and InN compounds. The alternative form of GGA proposed by Engel and Vosko (EV-GGA), and the modified Becke-Johnson exchange potential+LDA-correlation (MBJLDA) were also used for the electronic band structure and optical properties. The results obtained for structural, electronic and optical properties are compared with other computational work and experimental data. These compounds are direct band gap semiconductors, where the valence band maximum is located at the Gv point, and the conduction band minimum is located at the Gc point. In addition to that, detailed descriptions of the band structures, density of states and electronic charge densities were evaluated. The optical properties of these compounds, namely the real and the imaginary parts of the dielectric function, reflectivity and absorption coefficient were analyzed