Ab initiodesign of half-metallic fully compensated ferrimagnets: The case ofCr2MnZ(Z=P, As, Sb, and Bi)

Abstract

Electronic structure calculations from first principles are employed to design half-metallic fully compensated ferrimagnets (or, as they are widely known, half-metallic antiferromagnets) susceptible of finding applications in spintronics. ${\mathrm{Cr}}_2\mathrm{Mn}Z$ $(Z=\mathrm{P},\mathrm{As},\mathrm{Sb},\mathrm{Bi})$ compounds have 24 valence electrons per unit cell and calculations show that their total spin moment is approximately zero for a wide range of lattice constants, in agreement with the Slater-Pauling behavior for ideal half-metals. Simultaneously, the spin magnetic moments of Cr and Mn atoms are antiparallel and the compounds are ferrimagnets. Mean-field approximation is employed to estimate their Curie temperature, which exceeds room temperature for the alloy with Sb. Our findings suggest that ${\mathrm{Cr}}_2\mathrm{Mn}\mathrm{Sb}$ is the compound of choice for further experimental investigations.