Structural,electronic,optical,and magnetic properties of Co-doped Cu_2O

We investigate the magnetic properties of Co-doped Cu₂O. We studied first the electronic and structural properties of Cu₂O using the optimization of the lattice constant which is 4.18 Å. The calculated gap is found between 0.825 eV and 1.5 eV, these values are in good agreement with the experimental results. The Co atoms are inserted in Cu₂O by means of the density functional theory (DFT) using LSDA, LSDA+U, and LSDA+MBJ approximations in the WIEN2k code, based on the supercell model by setting up 12, 24, and 48 atoms in (1×1×2), (1×2×2), and (2×2×2) supercells respectively with one or two copper atoms being replaced by cobalt atoms. The energy difference between the ferromagnetic and anti-ferromagnetic coupling of the spins located on the substitute Co has been calculated in order to obtain better insight into the magnetic exchange coupling for this particular compound. The studied compound exhibits stable integer magnetic moments of 2 μ_B and 4 μ_B when it is doped with 2 atoms of Co. Optical properties have also been worked out. The results obtained in this study demonstrate the importance of the magnetic effect in Cu₂O.