First principle investigations of structural, electronic and magnetic properties of Cr doped zinc-blende MgTe ternary alloys with DFT based FP-LAPW approach

Abstract

First principle calculations of structural, electronic and magnetic properties of transition metal Cr doped MgTe ternary alloys have been performed using density functional FP-LAPW methodology. The exchange–correlation potentials for ground state structural properties of CrxMg1-xTe (x = 0.0, 0.25, 0.50, 0.75, 1.0) alloys have been calculated with Wu-Cohen generalized-gradient approximation (WC-GGA) scheme, while those for electronic and magnetic properties with modified Becke-Johnson (mBJ)-GGA scheme. Calculations suggested that the CrxMg1-xTe compounds possess ferromagnetic zinc-blende structures. The analyses of density of states (DOS) show that spin polarisation of electron in Cr-d orbitals are responsible for the half-metallic ferromagnetic characters. In the study of magnetic properties, total magnetic moments of ternary alloys and their constituent atoms have been calculated and found that the major contribution comes from the Cr atom in each ternary alloy. The spin-exchange constant N0α and N0β have been calculated in order to validate the effects of exchange splitting in the specimens. Present calculations indicate that the ternary alloys are potential magnetic materials for various half-metallic ferromagnetic and spintronic applications.