Effect of PbO on the B2O3-TeO2-P2O5-BaO-CdO-Sm2O3 glasses - Structural and optical investigations

This paper reports the effect of lead oxide on the optical properties of Sm3 + doped (60-x) B2O3-xPbO-14TeO2-10P2O5-7.5BaO-7.5CdO-1Sm2O3 (SBTXL) glasses. The SBTXL glasses were prepared with different concentrations of PbO, varied from 0 to 40 wt%. The FTIR spectra reveal significant structural changes (e.g., BO3, BO4, PbO4, TeO3 and TeO4) in the glass induced by the inclusion of lead oxide. The UV-Vis-NIR absorption spectra were used to calculate the oscillator strength, bonding parameters (δ), nephelauxetic ratio (β) and Judd-Ofelt parameters. The negative values of bonding parameter (δ) suggest predominant ionic nature of binding of the Sm3 + ions. A deep red luminescence is observed from 4G5/2 → 6H7/2 transition of Sm3 + ions in the title glasses. The luminescence intensity increases with increase in the concentration upto 0 to 20 wt% and beyond that, concentration quenching is observed. Judd-Ofelt parameters follow the trend as Ω4 > Ω6 > Ω2. Higher symmetry is observed for the lower values of Ω2 and Red/Orange ratio. The Ω2 parameter and red-to-orange intensity ratio (R/O) of the Sm3 + emission depend on the PbO content in the SBTXL glasses. The SBT20L glass has higher stimulated cross-section and gain bandwidth. The optical gain parameter (35.4 × 10− 25 cm2 s) of the SBT20L glass is found to be higher than the other Sm2O3 doped glass systems. The CIE colour coordinates fall in the reddish orange region.