The optical absorption and fluorescence properties of Sm³⁺ ions in LiFMO-B₂O₃ (MO= CaO, CdO, BaO and PbO) glasses

Lithium fluoroborate glasses mixed with the four different modifier oxides viz., CaO, CdO, BaO and PbO doped with Sm₂O₃ were prepared. Optical absorption and photoluminescence spectra of these glasses have been studied. From the measured intensities of various absorption bands of these glasses the Judd–Ofelt parameters Ω₂, Ω₄ and Ω₆ have been evaluated and compared with those of other reported glass systems. The Judd–Ofelt theory could be successfully applied to characterise the absorption and luminescence spectra of these glasses. From this theory various radiative properties like transition probability A, branching ratio β_r, the radiative life time τ_R, and the emission cross section σ_E for various emission levels of these glasses have been determined and reported. The comparison of the values the branching ratio, β_r for the transition ⁴G_5/2 → ⁶H_9/2, for the four glasses show the largest value for glass containing PbO indicating these glasses to exhibit better lasing action among the four glasses. (author)