LUMINESCENCE AND ENERGY-TRANSFER IN TM DOPED CRYSTALS

Concentration series of YLF:Tm and YLF:Tm-Ho crystals were examined. T he intraionic transition probabilities and interionic energy transfer processes were studied both theoretically and experimentally. The meth od of quantum mechanical modelling was employed for theoretical calcul ations. On the basis of experimental data and theoretical estimates, t he predominant mechanism of energy transfer was determined. Concentrat ion dependence of the rate of luminescence self-quenching was calculat ed and compared with the data obtained from the luminescence decay cur ves. Tm-Ho energy transfer rate in co-doped crystals for the lowest Tm and Ho energy levels was examined. Good agreement between the experim ental and calculated data was obtained in all cases.