EFFECT OF NETWORK MODIFIER ON SPONTANEOUS EMISSION PROBABILITIES OF ER3+ IN OXIDE GLASSES

Compositional dependence of spontaneous emission probabilities of Er3+ was studied for silicate, borate, and phosphate glasses using the Judd-Ofelt theory. Through all of the glass systems, spontaneous emission probabilities of the I-4(3/2) --> I-4(15/2), I-4(9/2) --> I-4(J), and S-4(3/2) --> I-4(J) (J = 9/2, 11/2, 13/2, 15/2) transitions increased with increased ionic packing ratio of the glass host, which varied markedly with the type of network modifier. The effect of Er-O covalency on the transition probabilities was discussed from the spectral profile of the I-4(15/2) --> S-4(3/2) transition in terms of nephelauxetic effect.