COMPOSITIONAL DEPENDENCE OF JUDD-OFELT PARAMETERS IN SILICATE, BORATE, AND PHOSPHATE CLASSES

Judd-Ofelt parameters Omega(t) with t = 2, 4, 6 for the rare-earth ions pr(3+), Nd3+, Sm3+, Tb3+, Dy3+, Ho3+, Er3+, and Tm3+ in alkali and/or alkaline earth silicate, borate, and phosphate glasses have been determined. The variations of Omega(t) with the number of 4f electrons of the rare-earth ions are demonstrated, and factors affecting the Judd-Ofelt parameter Omega(6) are discussed. The intensity parameter Omega(6) depends on the ionic packing ratio of the glass host by changing modifier type in silicate and borate glasses, and it is independent of that in a series of borate glasses as a function of modifier content and phosphate glasses. The peak wavenumbers of the transitions whose intensities are determined mainly by the Omega(6)[\\U-(6)\\](2) term-where [\\U-(6)\\] is one of the reduced matrix elements-shift systematically with the values of Omega(6) for all the rare-earth ions.