First principles study on electronic structure and optical properties of quaternary arsenide oxides YZnAsO and LaZnAsO

The electronic structure and optical properties of the tetragonal phase quaternary arsenide oxides YZnAsO and LaZnAsO were studied using density-functional theory (DFT) within generalized gradient approximation (GGA). The band structure along the higher symmetry axes in the Brillouin zone, the density of states (DOS) and the partial density of states (PDOS) were presented. The calculated energy band structures show that both YZnAsO and LaZnAsO are indirect gap semiconductors with band gap of 1.173 1 eV and 1.166 5 eV, respectively. The DOS and PDOS show the hybridization of Y-O/La-O atom orbits and Zn-As atom orbits. The dielectric function, reflectivity, absorption coefficient, refractive index, electron energy-loss function and optical conductivity were presented in an energy range from 0 to 25 eV for discussing the optical properties of YZnAsO and LaZnAsO.