Optical studies of Pr3+ doped oxyfluoroborate glass

Pr³⁺ doped oxyfluoroborate glasses have been prepared with different concentrations of Pr. The absorption, fluorescence, and photoacoustic spectra have been recorded and lifetimes of some levels were measured. The fluorescence decays were found to be non-exponential for the ³P₀ level. Fluorescence quenching was observed for higher concentrations of the Pr³⁺ ion in the glass due to the energy transfer processes from an excited rare earth ion to a neighbouring one. The mechanism of energy transfer is determined by applying the Inokuti-Hirayama model and is found to involve a quadrupole-quadrupole type of interaction.