Optical absorption, excitation and emission spectra of Eu3+ ions in lithium
berate and lithium fluoroborate glasses have been investigated. Judd-Ofelt
intensity parameters are derived from the integrated absorption spectra an
d also from the emission spectra under various constraints. The relative me
rits of thermal correction to the oscillator strengths of the transitions o
riginating from the ground state (F-7(0)) Of Eu3+ ion observed in the absor
ption spectra have been discussed. The Judd-Ofelt parameters obtained from
the emission spectra have been used to calculate the total spontaneous emis
sion probabilities (A), lifetimes (tau(R)) and branching ratios (beta(R)) f
or eight excited levels that include, K-5(6), P-3(0), H-5(3), L-5(7), D-5(3
), D-5(2), D-5(1) and D-5(0). The predicted values of tau(R) and beta(R) ar
e compared with the measured values for D-5(0) level. The stimulated emissi
on cross-sections (sigma (lambda(p))) are also evaluated for the D-5(0) -->
F-7(J) and D-5(1) --> F-7(J) transitions. The variation of optical propert
ies with compositional changes of lithium oxide and lithium fluoride conten
ts in the glasses are discussed and compared with similar results. (C) 2000
Elsevier Science B.V. All rights reserved.