Spectral analysis of Eu 3+:B 2O 3–Al 2O 3– MF 2 ( M = Zn, Ca, Pb) glasses

Abstract

The influence of glass composition on the optical properties of Eu 3+-doped borate glasses modified with Zn 2+, Ca 2+ and Pb 2+ cations has been investigated. These glasses have been prepared by melt quenching technique and characterized through optical absorption, photoluminescence and decay times. An intense red luminescence is observed from the 5D 0 emitting level of Eu 3+ ions in these glasses. The relative luminescence intensity ratio of 5D 0 → 7F 2 to 5D 0 → 7F 1 transitions has been evaluated to estimate the local site symmetry around the Eu 3+ ions. Judd–Ofelt parameters have been evaluated from the absorption spectra. These parameters have been used to derive radiative properties such as transition probabilities, branching ratios, radiative lifetimes and peak stimulated emission cross-sections for the 5D 0 → 7F J ( J = 0, 1, 2, 3 and 4) transitions. Decay curves of the 5D 0 level of Eu 3+ ions in these three glass systems have been measured by monitoring the 5D 0 → 7F 2 transition at room temperature.