Optical absorption and emission properties of Pr 3+ and Er 3+ in lithium cesium mixed alkali borate glasses

Abstract

This article presents the optical absorption and emission properties of Pr 3+ and Er 3+ in mixed alkali borate glasses of the type 68B 2O 3· xLi 2O·(32- x)Cs 2O (where x = 8 , 12, 16, 20 and 24). The variation of Judd–Ofelt intensity parameters ( Ω λ ), the peak wavelength of the hypersensitive transitions, radiative transition probabilities ( A rad) and peak emission cross-sections ( σ p) with x in the glass matrix have been discussed in detail. The changes in position of hypersensitive transition and intensity parameters with x are correlated to the structural changes in the host matrix. The estimated radiative lifetimes ( τ R) of certain excited states of both Pr 3+ and Er 3+ in lithium cesium mixed alkali borate glasses are reported. Branching ratios ( β) and integrated absorption cross-sections ( Σ) for certain important transitions are presented. Peak stimulated emission cross-sections ( σ p) are calculated for the observed emission peaks of Pr 3+ and Er 3+ ions in this glass matrix.