Radiative properties and luminescence spectra of Sm3+ ion in zinc-aluminum-sodium-phosphate (ZANP) glasses

The fluorescence properties of different concentrations of Sm3+ doped zinc-aluminum-sodium-phosphate (ZANP) glasses were studied by the XRD, SEM, FTIR, TG-DTA, optical absorption, photoluminescence and decay cure analysis. X-ray diffraction profiles and SEM images confirmed the amorphous nature of the glass samples. Structural information of these glass matrices was provided by FTIR spectrum. Judd-Ofelt (J-O) theory was applied to the experimental oscillator strengths to evaluate three phenomenological J-O intensity parameters, Ωλ (λ=2, 4 and 6). Using J-O intensity parameters and emission spectra, various radiative parameters such as radiative transition probabilities (AR), radiative lifetimes (τR), calculated and measured branching ratios (βR and βm), effective bandwidths (Δλeff) and stimulated emission cross-sections (σP) were calculated for observed emission transitions. The intensity of emission transitions with the variation of Sm3+ ion concentration was studied. The nature of decay curves of 4G5/2 level for different Sm3+ ion concentrations in ZANP glass was analyzed and obtained measured lifetimes (τexp). Quantum efficiency of 4G5/2 level was calculated based on experimental and measured radiative lifetimes (τexp and τR).