Half-metallic antiferromagnetism in the ordered Cr1 − xCaxSb alloy from first-principles calculations

Compared to half-metallic ferromagnets, half-metallic antiferromagnets (precisely called half-metallic fully compensated ferrimagnets) are more promising candidates for spintronic applications since their zero magnetization leads to lower stray fields and thus tiny energy losses. Using the first-principles calculations, we have systematically investigated the electronic and magnetic properties of the ordered Cr_1 − xCa_xSb alloy. It is found that Cr_1 − xCa_xSb with x=0.125, 0.25, 0.5 and 0.75 all are half-metals like zinc-blende CrSb and CaSb. Interestingly, Cr_0.25Ca_0.75Sb is a half-metallic antiferromagnet with complete spin polarization, and the half-metallic antiferromagnetism is robust against the lattice compression and expansion and the choice of electronic exchange and correlation functional.