Novel approach towards cross-relaxation energy transfer calculation applied on highly thulium doped tellurite glasses

In this paper we calculated, for the first time to the best of our knowledge, the cross relaxation parameter of Tm3+ ions in tellurite glasses over a wide range of concentrations: from 0.36 mol% up to 10 mol%. A new measurement approach based on emission spectra monitoring is proposed. This method is very simple and allows to measure even very highly doped samples. The obtained values of cross-relaxation parameter show a linear dependence with respect to dopant concentration over the full investigated interval, suggesting a dipole-dipole interaction process. The measured slope is 1.81x10^−17 cm^3 s^−1 mol%^−1.