High-TC fully compensated ferrimagnetic semiconductors as spin-filter materials: the case of CrVXAl (X = Ti, Zr, Hf) Heusler compounds

Abstract

We extend our recent work on spin-filter materials (Galanakis et al 2013 Appl. Phys. Lett. 103 142404) to the case of CrVXAl (X = Ti, Zr, Hf) compounds, for which, using ab initio electronic structure calculations, we show that p-d hybridization leads to the formation of a fully compensated ferrimagnetic semiconducting state with moderate exchange splitting. The magnetism is of covalent-type and the very strong antiferromagnetic Cr-V exchange interactions lead to extremely high Curie temperature, T-C, values. Furthermore, all three compounds are thermodynamically and magnetically stable. The combination of very high T-C values with a zero total net magnetization makes them promising materials for spintronics applications.