A first principles study on the full-Heusler compound Mn2CuSb

Electronic structure calculations from first-principles are employed to design half-metallic ferrimagnets susceptible of finding applications in spintronics. The electronic structure and magnetism properties of a new Mn-based Heusler alloy Mn2CuSb are studied and both possible L21 structures (CuHg2Ti and AlCu2Mn types) are taken into account. It is found that the CuHg2Ti-type structure is energetically more favorable than the AlCu2Mn-type structure and presents half-metallic character. Calculations show that their total spin moment is −2.00μB for a wide range of equilibrium lattice constants and the total spin magnetic moment is attributed mainly to the two Mn atoms. Simultaneously, the small spin magnetic moments of Cu and Sb atoms are parallel and the compound is ferrimagnets. The total spin moment mainly origins from the antiparallel configurations of the Mn partial moments. The CuHg2Ti-type Mn2CuSb alloy keeps a 100% of spin polarization of states at the Fermi level. Our findings suggest that Mn2CuSb may be a promising material for future spintronic applications.

Research highlights
► We study the electronic structure and magnetism properties of a new Mn-based Heusler alloy Mn2CuSb.
► Minimize energy show that the CuHg2Ti-type structure is energetically more favorable than the AlCu2Mn-type structure.
► The density of states present the CuHg2Ti-type structure keeps a 100% of spin polarization of states at the Fermi level.
► The lattice constant dependence of magnetic moment exhibit that the total spin moment of CuHg2Ti-type structure is −2.00 for a wide range of equilibrium lattice constants.
► A total spin moment mainly origins from the antiparallel configurations of the partial moments of Mn atoms.