First principle study of optical properties of Cu doped zincblende GaN for novel optoelectronic applications

Current computational study is focused on calculation of optical properties of Cu doped zincblende GaN system where PBE-GGA approximation is employed in Wien2K code. We consider various Cu concentrations 6.25 %, 3.12 %, 1.56 % corresponding to 1 x 1 x 2, 1 x 2 x 2, 2 x 2 x 2 supercell configurations respectively. We substitute one Ga atom with one Cu atom in each concentration and we present a good comparison among optical properties of pure GaN and all Cu concentrations. TDOS and PDOS plots reveal contribution of Ga p-states, N p-states and Cu d-states. Optical absorption shows redshift in comparison to pure GaN and because of interactions of Cu and N atoms, we inspect localized d-states at minima of conduction band or Fermi level. Hence, electro-optical properties of zincblende GaN are enhanced upon addition of impurity (Cu) and the material may potentially be used in photonic, power electronics, solar cells, optoelectronics, UV photodetectors and LEDs.