Revisiting energy transfer in Tm-doped aluminosilicate glass fiber II: variation of the Tm-doping concentration

We extend our model that aims to quantify energy transfer in the Tm 3+ -doped aluminosilicate glass system to the analysis of a range of Tm 3+ concentrations spanning more than an order of magnitude. We introduce energy migration to the model and find that its rate parameter has a linear dependence on the Tm 3+ concentration, in contrast to energy transfer upconversion and in particular cross relaxation which vary nonlinearly. When we compare our results of the cross relaxation rate with those reported in the literature for other glass and crystal hosts, we find that the functional dependence with the Tm 3+ concentration is markedly different, suggesting that the host composition of aluminosilicate glass presents unique energy transfer properties for Tm 3+ -doped fibers.