Electronic structure and optical properties of Ce-doped AlN studied by first-principles

Abstract

In order to explore the potential applications of AlN in optoelectronic devices, the electronic structure and optical properties of wurtzite AlN with different Ce doping concentrations (denoted as Al1−xCexN, where x is the atomic percentage concentration of Ce) were calculated by first-principles. The results show that the supercell volume of Al1−xCexN increases with the increase of Ce doping concentration，while the bandgap does the opposite. The static dielectric constant of Al1−xCexN is smaller than that of the intrinsic AlN. As Ce doping concentration increases, the peak intensity of reflectivity, refractive index and absorption coefficient decreases, and the peaks shift to lower energy. The energy-loss spectra of Al1−xCexN exhibit obvious plasma oscillation features, and the peaks are lower than that of the intrinsic AlN. The photoconductivity of Al1−xCexN increases sharply in the low-energy region with the increase of energy.