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Abstract: Glasses having composition 20ZnO·xBi2O3·(79.5− x)B2O3·0.5Pr6O11 were prepared by melt quench technique. The amorphous nature of the prepared glass samples was confirmed by X-ray diffraction. The spectroscopic properties of these glasses were investigated by recording optical absorption and fluorescence spectra. The structural investigations of the glasses were carried out by recording the IR spectra. The optical properties of Pr3+ ions doped zinc borate glasses with varying concentration of bismuth oxide have been studied. The Judd–Ofelt intensity parameters Ω λ (λ =2, 4, 6) and other radiative properties like radiative transition probability, radiative life time, branching ratio and stimulated emission cross-section of the prepared glasses have been calculated. The variation of Ω 2 with Bi2O3 content has been attributed to changes in the asymmetry of the ligand field at the rare earth ion site and to the changes in their rare earth oxygen (RE-O) covalency. The branching ratio for 3P0 → 3F2 transition is 42% and the predicted spontaneous radiative transition probability rates are fairly high (14,347–14,607s−1). This is beneficial for lasing emission. The stimulated emission cross-section for all the emission bands has been calculated. [Copyright &y& Elsevier]

Abstract: This article presents the optical absorption and emission properties of Pr3+ and Nd3+ doped two different mixed alkali chloroborate glass matrices of the type 70B2O3·xLiCl·(30− x)NaCl and 70B2O3·xLiCl·(30− x)KCl (x =5, 10, 15, 20 and 25). The variation of Judd–Ofelt parameters (Ω 2, Ω 4 and Ω 6), total radiative transition probabilities (A T), radiative lifetimes (τ R) and emission cross-sections (σ p) with the variation of alkali contents in the glass matrix have been discussed in detail. The changes in the peak wavelengths of the hypersensitive transition and intensity parameters with x are correlated to the structural changes in the host matrix. The estimated radiative lifetimes of certain excited states of Pr3+ and Nd3+ in these two glass matrices are reported. Peak stimulated emission cross-sections (σ P) are reported for the observed emission transitions of Pr3+ and Nd3+ ions. Branching ratios (β) of the observed emission transitions obtained from the Judd–Ofelt theory are compared with the values obtained from the emission spectra. [Copyright &y& Elsevier]