Half-metallic ferromagnetism in wurtzite and rocksalt TiTe: A density functional theory study

Abstract

The electronic and magnetic properties of TiTe in wurtzite (WZ) structure are investigated on the basis of density functional theory and first principle calculations. In order to find the most stable structure of this compound, we consider it in structures other than the WZ structure and we find that the most stable phase is the NiAs structure. The results of our calculations show that WZ-TiTe is a half-metallic ferromagnet with a magnetic moment of 2μB per formula unit. We also consider its properties under stress to find out whether it is possible to manufacture it over semiconductors with WZ structure or not. We find out that it maintains its half-metallicity under high stresses. The Curie temperature of WZ-TiTe is also estimated within mean field approximation to be higher than room temperature. We also consider the properties of rocksalt (RS) TiTe at its equilibrium lattice constant and under negative stress. The results of our calculations show that although RS-TiTe is a metal at its equilibrium lattice constant, it becomes a half-metal with large spin-flip gap under negative stress. All of these properties cause WZ and RS-TiTe to be possible candidates for spintronic and nanospintronic devices.