Optical properties of the Tm3+ and energy transfer between Tm3+→Pr3+ ions in P2O5-CaO-SrO-BaO phosphate glass

► The energy transfer between Tm3+ and Pr3+ in phosphate glasses (which exhibit a variety of transfer efficiencies) was studied. ► The experimental quantum efficiencies of the luminescence of Tm3+ η0 and (Tm3+, Pr3+) doped phosphate glasses were measured to give η/η0 = 0.447, 0.305, and 0.179 for (0.4 mol% Pr3+, 1.0 mol% Tm3+), (0.8%Pr3+, 1.0%Tm3+) and (1.6 mol% Pr3+, 1.0 mol% Tm3+), respectively. ► In order to verify the nature of the ion coupling in our phosphate glass system, we applied the Inokuti-Hirayama model. ► The non-radiative energy transfer rate from Tm3+ to Pr3+, transfer efficiencies, and the donor-acceptor distance have been calculated and compared with obtained experimental data.