LUMINESCENCE OF TERBIUM-ACTIVATED ALKALI RARE-EARTH META-PHOSPHATE GLASSES

Excitation and emission spectra of Tb3+ were measured in alkali yttrium terbium metaphosphate glasses having the general composition n(M2O • P2O5) [(1 - x) Y2O3 • xTb2O3 • 3P2PO5]. The effects of Tb concentration, Ce codoping, and alkali and its concentration on the intensities of Tb3 + emission at the 4f-5d transition bands were investigated. The Tb3+ emission was anomalously enhanced at a Tb concentration where the population of Tb3+-Tb3+ pairs becomes maximum. Sensitization of Tb3+ emission at the f-d bands was found to take place at a very low Ce concentration (<100 ppm), whereas the sensitization via the direct energy transfer from the Ce3 + absorption band occurred at higher Ce concentrations. The intensities of Tb3 + emission was found to increase in the order of Li, Na, K, when n is fixed, and with increasing alkali, when M is fixed. © 1979, The Electrochemical Society, Inc. All rights reserved.