The effect of host glass on optical absorption and fluorescence ofNd3+ inxNa2O–(30−x)K2O–70B2O3 glasses

Abstract

The effect of host glass composition on the optical absorption and fluorescence spectra ofNd3+ has been studied in mixed alkali borate glasses of the typexNa2O–(30−x)K2O–69.5B2O3–0.5Nd2O3 (x = 5,10, 15, 20 and 25). Various spectroscopic parameters such as Racah(E1,E2 andE3), spin–orbit(ξ4f) and configurationinteraction (α,β) parameters have been calculated. The Judd–Ofelt intensity parameters(Ωλ) have been calculated and the radiative transition probabilities(Arad),radiative lifetimes(τr), branching ratios(β) and integratedabsorption cross sections (Σ) have been obtained for certain excited states of theNd3+ ion and are discussedwith respect to x.From the fluorescence spectra, the effective fluorescence line widths(Δλeff) and stimulatedemission cross sections (σp) have been obtained for the three transitions , and of Nd3+. The stimulated emissioncross section (σp) values arefound to be in the range (2.0–4.8) × 10−20 cm2 and they are large enough to indicate that the mixed alkali borate glasses could bepotential laser host materials.