Spectroscopic properties and Judd-Ofelt analysis of Sm3+ doped lead-germanate-tellurite glasses

Spectroscopic properties of Sm3+ (1 mol%) ions in 49 PbO-30 GeO2-20 TeO2 glass have been characterized through optical absorption and temperature dependent fluorescence. The spectroscopic parameters such as oscillator strengths (f), Judd-Ofelt (J-O) intensity parameters (Ωλ), spontaneous emission probability (AR), branching ratios (βR) and radiative lifetimes (τR) of various excited levels have been determined from the absorption spectrum by using J-O analysis. From the fluorescence spectra, four emission transitions have been observed from the 4 G5/2 state to the lower lying states 6H5/2, 6H7/2, 6H9/2 and 6H11/2 upon exciting the sample with a 488 nm line of an argon ion laser. The stimulated emission cross-sections (σe) and branching ratios (βmeas) were estimated from the emission spectra for all emission transitions and decay curve analysis for the 4G5/2 level has also been carried out for different concentrations. Based on these results, the utility of Sm3+ doped lead-germanate-tellurite glasses as laser active materials in the visible region is discussed