Half metallic properties of the quaternary CuFe2GaSe4 chalcogenide compound

The structural, electronic and magnetic properties of quaternary CuFe2GaSe4 in stannite structure (tetragonal structure, space group I4¯2m) were investigated using the full potential augmented plane wave plus local orbitals method based on density functional theory. For exchange-correlation potential, the local spin density approximation LSDA and LSDA+U schemes were adopted. It is shown that the application of the Coulomb interaction U increases the lattice parameters relative to the LSDA approach. The analysis of the densities of states shows that this compound is semiconductor and metallic in the majority and minority spin channels, respectively. This half metallicity of the majority spin exhibits a direct band gap of Eg = 0.62 eV, and a magnetic moment of 8 μB. The magnetism comes from the d orbitals of Fe atoms and the p-Se, d-Fe coupling. These results may be of interest for spintronic applications.