The effect of defects on the magnetic properties and spin polarization of Ti2FeAl Heusler alloy

The effect of antisite, swap and vacancy defects on the magnetic properties and spin-polarization of the full-Heusler Ti2FeAl alloy with the Hg2CuTi-type structure is studied by using the first-principles calculations within density functional theory. The perfect Ti2FeAl Hensler alloy exhibits a ferromagnetic half-metallic behavior with the total magnetic moment of 1(mu B) and indirect band gap of 0.543 eV. Among swap detect, only the total magnetic moment of the Ti-2-Al swap defected is close to the perfect alloy. All defected structures destroy the half-metallicity and only Al-Ti1 and Al-Ti2 antisite and Fe vacancy defects maintain relatively high spin polarization. (C) 2013 Elsevier B.V. All rights reserved.