Optical spectroscopy and luminescence properties of Sm3+-doped lead-germanate glasses

Glasses of 1-mol% Sm3+ -doped lead germanate glasses 49 PbO-50. GeO2, 49 PbO-30 GeO2-20 Ga2O3 and 49 PbO-30 GeO2-20 B2O3 (in mol%) have been prepared by using the conventional melt quenching method. A Judd-Ofelt (JO) analysis for Sm3+ ions in lead-germanate glasses has been performed on the basis of the absorption spectrum. Fluorescence and lifetime measurements have been carried out using an argon-ion laser. Efficient visible emissions were observed, and the stimulated emission cross sections, branching ratios and quantum efficiencies were determined. In the present work, the relatively high values of the emission cross sections (sigma(e)) suggest that these materials can be considered as interesting candidates for optical applications. A comparison of the lasing properties of these three lead germanate glasses and their utilities as laser active materials are shown and analyzed.