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 ion s pr(3+), Nd3+, Sm3+, Tb3+, Dy3+, Ho3+, Er3+, and Tm3+ in alkali and/o r alkaline earth silicate, berate, and phosphate glasses have been det ermined. 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 mo difier type in silicate and berate glasses, and it is independent of t hat in a series of berate glasses as a function of modifier content an d phosphate glasses. The peak wavenumbers of the transitions whose int ensities are determined mainly by the Omega(6)[\\U-(6)\\](2) term-wher e [\\U-(6)\\] is one of the reduced matrix elements-shift systematical ly with the values of Omega(6) for all the rare-earth ions.