Spectral, Thermal and Upconversion Properties of Dy3+ Doped Borotellurite Glasses with Large Stability Parameter

Glass sample of yttrium zinc lithium lead sodium alumino borotellurite (25-x) TeO2:10ZnO:10Li2O:10PbO:10Na2O:10Al2O3:10Y2O3:15B2O3:xDy2O3. (wherex=1,1.5 and 2 mol%) have been prepared by melt-quenching technique. The amorphous nature of the prepared glass samples was confirmed by X-ray diffraction. Optical absorption, excitation spectrum and fluorescence spectra were recorded at room temperature for all glass samples. Judd-Ofelt intensity parameters Ωλ (λ=2, 4 and 6) are evaluated from the intensities of various absorption bands of optical absorption spectra. Using these intensity parameters various radiative properties like spontaneous emission probability, branching ratio, radiative life time and stimulated emission cross–section of various emission lines have been evaluated