First-principles calculations on half-metal ferromagnetic results of VZrAs and VZrSb half-heusler compounds and Al1-xMxAs (M= Co, Fe and x = 0.0625, 0.125, 0.25) diluted magnetic semiconductors

Abstract

The theoretical calculations on structural, electronic, half-metallic and elastic properties of both VZrAs, VZrSb half-Heusler compounds and Al1-xFexAs and Al1-xCoxAs (x = 0.0625, 0.125, 0.25) diluted magnetic semiconductors (DMSs) have been investigated using WIEN2k. In Al1-xFexAs and Al1-xCoxAs (x = 0.0625, 0.125, 0.25) DMSs, the ferromagnetic phases are more stable than non-magnetic and antiferromagnetic phases. In VZr(As, Sb) compounds, the ferromagnetic (FM) phases in Type II structure are more stable energetically. The spin-up electrons of both half-Heusler compounds have semiconducting nature with 0.643 and 0.799 eV energy gaps while spin-down electrons of Al0.875Fe0.125As, Al0.9375Fe0.0625As and Al1-xCoxAs (x = 0.0625, 0.125, 0.25) DMSs have semiconducting feature. The mechanically stability conditions are provided by all compounds except VZrAs half-Heusler compound. Therefore, VZrSb, Al1-xFexAs and Al1-xCoxAs (x = 0.0625, 0.125, 0.25) diluted magnetic semiconductors (DMS) are mechanically stable against the deformation. The VZrAs compound can be deformed in the experimental process since it does not provide the C11 > C12 mechanical stability condition. According to conditions of the ductility or brittleness of polycrystalline material, both VZrAs and VZrSb half-metal compounds are ductile materials while Al1-xFexAs and Al1-xCoxAs (x = 0.0625, 0.125, 0.25) DMSs are brittle. Finally, VZr(As, Sb), Al1-xCoxAs (x = 0.0625, 0.125, 0.25) and Al1-xFexAs (x = 0.0625, 0.125) compounds were obtained true half-metal ferromagnetic materials (HMF) within 4.00, 2.00 and 5.00 μB/f.u.