The influence of Ba2+ and Sr2+ ions with the Dy3+ ions on the optical properties of lead borate glasses: experimental and Judd–Ofelt comparative study

Two glasses compositions (50B 2 O 3 –30PbO–20SrO–xDy) and (50B 2 O 3 –30PbO–20BaO–xDy) where x = 0.0.5%, and 1.0% in wt.% ratio were prepared using melt quenching technique in order to investigate the effect of Ba 2+ and Sr 2+ ions in Dy 3+ ions doped lead borate glass. The optical properties such as bandgap and the refractive index distribution were examined using UV–vis-NIR absorption spectroscopy. The FTIR absorption spectra of all prepared samples were similar except for the metallic bands in the fingerprint region. The obtained experimental data were compared with theoretical data calculated by Judd–Ofelt framework. The Judd–Ofelt parameters Ωλ ( λ = 2, 4 and 6) were calculated and the trend was Ω 2 < Ω 4 < Ω 6 which is the common trend. The experimental oscillator strength ( f e x p ) , the calculated oscillator strength ( f c a l ) , the estimated refractive indexes (n) at each transition, the lifetime of radiative transitions ( τ ), the branching ratio ( β ), the absorption cross-section ( σ a b s ( λ ) ) and the emission cross-section ( σ e m i s ( λ ) ) were also estimated and discussed. The optical gain coefficient ( G ( λ ) ) was calculated not only for the most intense emission transition but also other emission peaks. The obtained results indicated that the prepared samples are promising materials for laser emission and optical communication applications.