FP‐LAPW investigations of Zn_1–xBe_xS, Zn_1–xBe_xSe and Zn_1–xBe_xTe ternary alloys

Abstract

Abstract The ab initio full potential linearized augmented plane wave (FP‐LAPW) method within density functional theory was applied to study the effect of composition on the structural and electronic properties of Zn 1– x Be x S, Zn 1– x Be x Se and Zn 1– x Be x Te ternary alloys. The effect of composition on lattice parameter, bulk modulus, band gap and effective mass was investigated. Deviations of the lattice constant from Vegard's law and the bulk modulus from linear concentration dependence were observed for all three alloys. It was deduced that increasing the Be composition in the alloys increases the hardness of the materials. In addition, the calculated band structures showed that the band gap undergoes a direct‐to‐indirect transition at a given concentration. Using the approach of Zunger and co‐workers, the microscopic origins of band gap bowing have been explained. The electron (hole) effective masses were also calculated. The band gap and effective mass were found to vary non‐linearly with Be composition. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)