First principles calculations of electronic and optical properties of Zr-doped La2O3

Abstract

Based on the density functional pseudopotential method, the structural properties, the band structure, the density of states, and the optical properties of pure and Zr-doped La2O3 were calculated. The calculation results indicate that the defect of La (Zr) exists steadily with a certain solubility. Zr substitution of the La sites induces effective reduction of the band gap of La2O3, the band gap being continuously reduced when increasing Zr doping level. The Fermi energy level shifts to the conduction band and exhibits metal-like characteristic after the Zr atom is introduced. The calculated optical properties indicate that red shifts are revealed in both the imaginary part of the dielectric function and the absorption spectra corresponding to the change of band gaps. Moreover, additional absorption is observed in the visible region, which implies that Zr-doped La2O3 might be a potential candidate for photoelectrical application. The calculation results are consistent with experimental results that have been reported.