Structural influence of yttria, scandia and hafnia on emission features of samarium ions in lead antimonate glass system

Luminescence features of samarium ions in non-conventional antimonate oxide glasses added with HfO₂, Y₂O₃ and Sc₂O₃ were investigated. From absorption and luminescence spectra various radiative parameters (associated with orange emission transition viz.,⁴G_5/2 → ⁶H_7/2) that give the information on luminescence efficiency of Sm³⁺ were calculated. The calculated values of radiative parameters are observed to be the largest for hafnia added glasses when compared with those of other two glasses. The infrared spectra have indicated that the trivalent antimony ions take part glass network forming positions with SbO₃ pyramids. The spectra further suggested the maximum concentration ofstructural defects in hafnia mixed glasses. Due to this reason, the vibrational losses (phonon losses) of PL output are expected to be decreased. The observed highest luminescence efficiency of Sm³⁺ ions in HfO₂ added glasses with respect to that of Y₂O₃ and Sc₂O₃ added antimonate glasses is attributed to this reason.