Excitation and luminescence of rare earth-doped lead phosphate glasses

Excitation and luminescence properties of Eu 3+ , Tb 3+ and Er 3+ ions in lead phosphate glasses have been studied. From excitation spectra of Eu 3+ ions, the electron–phonon coupling strength and phonon energy of the glass host were calculated and compared to that obtained by Raman spectroscopy. Main intense and long-lived luminescence bands are related to the 5 D 0 – 7 F 2 (red) transition of Eu 3+ , the 5 D 4 – 7 F 5 (green) transition of Tb 3+ and the 4 I 13/2 – 4 I 15/2 (near-infrared) transition of Er 3+ . The critical transfer distances, the donor–acceptor interaction parameters and the energy transfer probabilities were calculated using the fitting of the luminescence decay curves from 5 D 0 (Eu 3+ ), 5 D 4 (Tb 3+ ) and 4 I 13/2 (Er 3+ ) excited states. The energy transfer probabilities for Eu 3+ ( 5 D 0 ), Tb 3+ ( 5 D 4 ) and Er 3+ ( 4 I 13/2 ) are relatively small, which indicates low self-quenching luminescence of rare earth ions in lead phosphate glasses.