Structural, photoluminescence, and optical characteristics of a Sm 3+ -doped lead borate-strontium-tungsten glass system: Evaluation of Judd-Ofelt intensity parameters and radiative properties.

In this study, the melt quenching approach is used to synthesize a lead borate-strontium-based glass system doped with samarium ions. Modifications in the glass network structure arising from the addition of various concentrations of Sm ³⁺ ions were investigated via Fourier transform infrared (FTIR) spectroscopy. FTIR analysis revealed B-O-B bridges, BO ₃ , and BO ₄ units are present. UV-vis-NIR spectroscopic measurement was performed to study the optical absorption spectra. Optical constants such as optical bandgap energies, refractive indices, and other related parameters were evaluated. The lifetime fluorescence decay was measured and ranged between 1.04 and 1.88 ns. The photoluminescence spectra in the range 500-750 nm revealed four transitions from the ground state ⁶ G _5/2 to the excited states ⁶ H _5/2 , ⁶ H _7/2 , ⁶ H _9/2 and ⁶ H _11/2 and J-O theory was utilized to study these optical transitions for Sm ³⁺ ions. Calculations of the oscillator strengths and J-O intensity parameters were performed and the obtained J-O parameters followed the sequence Ω ₄  > Ω ₆  > Ω ₂ . The ratio O/R indicated a high lattice asymmetry around the samarium ions. The values of lifetimes and branching ratios for the fabricated samples emphasized their suitability to be used in laser applications. The current glass samples are good candidates for orange and red emission devices.
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