Theoretical Investigation of Half-Metallic Ferrimagnetic Heusler Alloys: the Case of DO3-Type Cr3Z (Z = P, As, Sb, S, Se, and Te)

We have carried out ab initio density functional theory (DFT) calculations on the DO3-type Cr3Z (Z = P, As, Sb, S, Se, and Te) alloys with the aim of predicting new half-metallic (HM) magnetic materials for potential spintronics applications. From the structural and magnetic calculations, we find that Cr3Z (Z = As, Sb, S, Se, and Te) alloys stabilized to ferrimagnetic (FiM) state, while Cr3P alloy stabilized in non-magnetic state. The spin-polarized density of states (DOS) calculation reveals that, among all the alloys, only the Cr3Sb exhibits HM-FiM nature at the equilibrium lattice constant with total integer magnetic moment of − 1 μB, satisfying the Slater-Pauling (S-P) rule and thus offering 100% spin polarization at the Fermi level. Further, both Cr3As and Cr3Te alloys show nearly half-metallic (NHM) behavior, while Cr3P, Cr3S, and Cr3Se alloys behave as usual metallic materials. Interestingly, in all the Cr3Z (Z = P, As, Sb, S, Se, and Te) alloys, the total magnetic moment is mainly contributed by Cr(Y) atoms. We also attempt to rationalize the origin for the observed HM band gap in terms of molecular orbital (MO) hybridization mechanism. Finally, the influence of sp atoms on the structural, electronic, magnetic, and half-metallic properties of Cr3Z (Z = P, As, Sb, S, S, and Te) alloys is studied systematically.