LAUSR

Abstract The oxyfluoride-lead-silicate-germanate glass with composition of 30SiO2–10GeO2–xPbO–(50-x)PbF2–10CdF2–yTm2O3, x = 5, 25, 45, y=0.01, 0.1, 0.5, 1.0 (mol. %) were prepared by melt-quenching technique and their spectroscopic properties, including parameters calculated by the JO method, were studied. A new approach for calculation of the pump efficiency of the 3F4 level at excitation of the 3H4 level by using stationary spectra of luminescence at transitions 3H4→3F4 and 3F4→3H6 was proposed. For the samples with a high content of Tm2O3, the efficiency reaches the value of 1.8. It was established that the quadrupole-quadrupole interaction between thulium ions dominates in the D-A energy transfer due to the cross-relaxation 3H4+3H6→3F4+3F4. On the base of the rate equations, a new fitting procedure was proposed for obtaining the probabilities of donor-acceptor, WDA, and up-conversion, WUP, energy transfer. It was obtained that WDA ∼6 105 1/s and WUP