Prediction of the Half Metallicity in Ferromagnetic Germanium Telluride (GeTe) Doped with Titanium

Abstract

This research work studies the structural, electronic and magnetic properties of Ge[Formula: see text]TixTe (for [Formula: see text], 0.50, 0.75, 1) compounds in rock-salt structure based on first-principles spin-polarized density functional theory. As it is implemented in WIEN2k code, the full-potential augmented plane-wave method was used in the investigation. To evaluate the structural properties of compounds, the exchange-correlation term is estimated using PBE-GGA approximation. For the other properties such as the electronic structures, densities of states and local moments, the generalized gradient approximation PBE-[Formula: see text] is used. The analysis of spin-polarized density of states has shown the half-metallic ferromagnetic character when [Formula: see text] and 0.75; while at [Formula: see text], we obtained near half-metallic behavior. In order to validate the effects resulting from exchange splitting process, we calculated the exchange constants [Formula: see text] and [Formula: see text]. For Ti atomics sites, the value of total magnetic moment has been estimated equal to [Formula: see text] in all studied compounds. We have found that the local magnetic moment of Ti is reduced and small local magnetic moments on nonmagnetic atomics sites of Ge and Te were created by the p-d hybridization effect.