OPTICAL-ABSORPTION, PHOTOLUMINESCENCE AND CROSS-RELAXATION OF PR3+ IONS IN SOME FLUORIDE GLASSES

The optical properties of Pr3+ in several heavy metal fluoride glasses have been measured at different temperatures and for different Pr3+ c oncentrations. Oscillator strengths (f) derived from absorption and ph otoluminescence measurements have been analysed using the Judd-Ofelt t heory as well as some modifications proposed by Kornienko et al. A rea sonable agreement among calculated and experimental 'f' values has bee n found. The decays of the photoluminescence emissions from the P-3(0) and D-1(2) levels after pulsed excitation have also been measured. No nexponential decays, due to cross relaxation effects, have been observ ed for PrF3 contents higher than 0.1 mol% in the case of the P-3(0) le vel and higher than 0.01 mol% for the D-1(2) level. The decay curves h ave been analysed using the Yokota-Tanimoto treatment and cross relaxa tion parameters for these two levels have been obtained in the differe nt glasses.