Electronic, magnetic, and structural properties of CrMnSb_0.5Si_0.5

Half-metallic Heusler compounds are among the most actively studied materials for applications in spin-based electronics. Largely, this is due to their high Curie temperature, and relative ease of fabrication. Here we theoretically study one such alloy CrMnSb_0.5Si_0.5. It is shown that the parent compound CrMnSb is not half-metallic in its ground state, however it undergoes a half-metallic transition under a uniform compression of ~1.5%. On practice, such compression could be induced by substituting the non-magnetic element (Sb) with another non-magnetic element of smaller radius (Si), e.g. in CrMnSb_0.5Si_0.5. Here, we demonstrate a thermodynamic stability of this compound, its half-metallic electronic structure, and ferrimagnetic alignment. At the same time, it is shown that in thin-film geometry the spin-polarization of this material is reduced due to the emergence of surface states in the minority-spin energy gap. These results may be useful for researchers working on practical applications in the field of spintronics.