First-principles study on electronic structure and optical properties of Lu-doped AlN

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