Abstract
Based on the pseudopotential formalism under the virtual crystal approximation, the composition dependence of electronic and optical properties of zinc-blende AlAsxSb1-x ternary alloys have been investigated. Good agreement is obtained between our results and the available experimental data. The absorption at the optical gaps suggested that AlAsxSb1-x is an indirect (Gamma-X) band gap semiconductor within a whole composition range. Besides, our results support the linear variation of the direct energy gap (Gamma-Gamma) previously assumed by many workers. The nature of the chemical bond is examined and discussed by means of the electron charge densities. The information derived from the present study may be useful for mid-infrared lasers applications. (C) 2013 Elsevier Ltd. All rights reserved.