First-principles study of the optical properties of YPO4 crystal with oxygen vacancies

In this study, in order to obtain more accurate optical spectrum line shapes, the defect formation energies of oxygen vacancies in YPO4 crystals with three different charges (0, +1, +2) were calculated using the finite-size correction scheme. The optical properties of the F center and F+ center were studied based on electron-phonon coupling. The emission peak calculated for the F+ center was close to the experimental value. The luminescence and absorption peaks were in the ultraviolet region for the F and F+ centers. We predicted that the absorption peak at 140 nm was related to the F center and that at 152 nm to the F+ center.