Theoretical study of the electronic and magnetic properties of Co2Cr1−xVxAl

We have investigated the electronic and magnetic properties of the doped Heusler alloys Co2Cr1−xVxAl(x=0, 0.25, 0.5, 0.75, 1) using first-principles density functional theory within the generalized gradient approximation (GGA) scheme. The calculated results reveal that with increasing V content the lattice parameter slightly increases; both cohesive energy and bulk modulus increase with increasing x. The magnetic moment of the Co(Cr) sites increases with V doping; the total spin moment of these compounds linearly decreases. We also have performed the electronic structure calculations for Co2Cr1−xVxAl with positional disorder of Co-Y(Cr,V)-type and Al-Y(Cr,V)-type. It is found that formation of Al-Y-type disorder in Co2Cr1−xVxAl alloys is more favorable than that of Co-Y-type disorder. Furthermore, we found that Co2Cr1−xVxAl of the L21-type structure have a half-metallic character. And the stability of L21 structure will enhance, however, the Curie temperature decreases as the V concentration increases. The disorder between Cr(V) and Al does not significantly reduce the spin polarization of the alloys Co2Cr1−xVxAl.