Study the electronic and magnetic properties of MnxZn1-xO supercell using first principle calculation

In this work, the electronic and magnetic properties of MnxZn1-xO at various manganese (Mn) concentrations were studied using first principle calculation. The computed equilibrium lattice constants values for 0% of Mn content were a = 3.29 angstrom and c = 5.25 angstrom which are slightly larger than the experimental value. Formation energies were found negative for different Mn concentrations which indicate the stability of the MnxZn1-xO supercell at our investigated percentages of Mn. Without Hubbard (U) correction, the obtained band gap of MnxZn1-xO at 0% Mn was 0.78 eV which is consistent with other theoretical reports and with Hubbard (U) correction the band gap was 3.38 eV which is compatible with experimental values. An oscillatory band gap was obtained with increasing Mn concentration. From 0% to 12.5% Mn, direct band gap was obtained while indirect band gap was obtained at 25%-50%. The density of states (DOS) was calculated and it reveals that O-p and Zn-d states in the valence band and Mn-d in the conduction band are contributed to decrease and increase of the band gap at different concentrations. The magnetic moment per Mn atom was found 5 mu B/Mn. The DOS calculations for spin up and spin down show asymmetric which indicates the ferromagnetic nature of the MnxZn1-xO supercell and spin density distribution confirms the increase of magnetism with Mn concentrations.