Structural and optical study of samarium doped lead zinc phosphate glasses

Samarium doped lead−zinc-phosphate glasses with composition (60−x)P2O5−20PbO−20ZnO−xSm2O3 (x=0, 0.5, 1.0, 3.0 mol%) were prepared by melt quenching technique. Density, refractive index and polaron radius of Sm3+ ions were calculated. The IR spectra reveal significant structural changes only for high concentration of samarium ions. Differential thermal analysis confirms the large structural changes in the glass due to the decrease of thermal stablility in presence of 3 mol% Sm3+ ions. UV-vis-NIR absorption spectroscopy was carried out and Judd-Ofelt analysis was performed. Radiative rates, branching ratio and lifetime of 4G5/2 were calculated by taking into account both electric and magnetic dipole contributions. Absorption spectra consist of seven absorption peaks corresponding to the transitions from the 6H5/2 ground state to various excited energy levels. Photoluminescence spectra show four prominent emission bands centered at 560, 597, 642 and 700 nm corresponding to the 4G5/2−6HJ (J=5/2, 7/2, 9/2, and 11/2) transitions respectively and the intensities of all bands are enhanced by Sm3+ ions content. The calculated values are compared to other reports, available in literature.