The optical absorption spectrum of Nd3+ ions in phosphate glasses of v
arying matrix environments has been recorded in the ultra violet, visi
ble and near infrared region. From the absorption spectra, various spe
ctroscopic parameters such as Slater-Condon (F-2, F-4 and F-6), spin-o
rbit (xi(4f)). Racab (E-1, E-2 and E-3), nephelauxetic (beta), bonding
(delta) and Judd-Ofelt (J-O) (Omega(2), Omega(4) and Omega(6)) intens
ity parameters were evaluated. Electric dipole S-ed and magnetic dipol
e (S-md) line strengths were evaluated with the help of J-O intensity
parameters. The observed and calculated oscillator strengths (f) are f
ound to be in reasonable agreement with one another. Using J-O paramet
ers and calculated matrix U-(lambda) radiative transition probabilitie
s (A), total radiative transition probability (A(T)), radiative lifeti
me (tau(RAD)) branching ratios (beta(R)) and integrated absorption cro
ss-sections for stimulated emission (sigma(a)) between the metastable
F-4(3/2) and terminal (4)J(J) levels were calculated. The analysis sho
ws that the F-4(3/2) --> I-4(11/2) has the potential for a laser trans
ition in the four glasses studied. The results of these investigations
have been confirmed by recording the fluorescence spectrum correspond
ing to the F-4(3/2) --> I-4(11/2) transition. (C) 1997 Elsevier Scienc
e B.V.