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

A P 2 O 5 -CaO-SrO-BaO phosphate glass doped with Tm 3+ and glasses doped with (Tm 3+ , Pr 3+ ) were used for this study. The photo-luminescence behaviors of Tm 3+ and Pr 3+ in phosphate glass were investigated by absorption, excitation and emission spectroscopy. The energy transfer between Tm 3+ and Pr 3+ in phosphate glasses (which exhibit a variety of transfer efficiencies) was studied. The experimental quantum efficiencies of the luminescence of Tm 3 + η 0 and (Tm 3+ , Pr 3+ ) doped phosphate glasses were measured to give η/η 0 = 0.447, 0.305, and 0.179 for (0.4 mol% Pr 3+ , 1.0 mol% Tm 3+ ), (0.8%Pr 3+ , 1.0%Tm 3+ ) and (1.6 mol% Pr 3+ , 1.0 mol% Tm 3+ ), 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 Tm 3+ to Pr 3+ , transfer efficiencies, and the donor–acceptor distance have been calculated and compared with obtained experimental data. As usual, the efficiency and the probability of energy transfer increase with the concentration of the acceptor.