M. Nikl et al., Radio- and thermoluminescence and energy transfer processes in Ce3+(Tb3+)-doped phosphate scintillating glasses, RADIAT MEAS, 33(5), 2001, pp. 593-596
Ce3+ and Tb3+-doped Na(K)-Gd phosphate glasses were synthesized and their r
adio-, photo- and thermoluminescence properties were investigated. Increase
d radioluminescence efficiency with respect to Gd-free glass matrix has bee
n achieved at Gd concentrations above 20 mol%. This is explained by efficie
nt capture of thermalised electrons and holes in the Gd3+-sublattice result
ing in the formation of Gd3+ excited states followed by Gd3+-Gd3+ energy tr
ansfer and single-step transfer to the Ce3+(Tb3+) emission centres. In such
a way non-radiative losses in the phosphate glass matrix are reduced. Ener
gy migration in Gd-sublattice becomes frozen below 10-15 K due to local fie
ld fluctuations in the glass matrix. Thermoluminescence measurements above
room temperature show the presence of two groups of traps with concentratio
ns strongly dependent on the glass composition. (C) 2001 Elsevier Science L
td. All rights reserved.