Modified Judd–Ofelt analysis of Pr3+ ions in mixed alkali chloroborophosphate glasses

Abstract

Absorption and emission properties of Pr3+ doped mixed alkali chloroborophosphate glasses have been reported in the UV-VIS-NIR region. A modified Judd–Ofelt (JO) approach has been employed to evaluate the intensity parameters Ωλ, from the experimentally determined oscillator strengths. These parameters are compared with those obtained from the standard JO theory. The evaluated JO parameters are utilized for the calculation of various radiative parameters such as radiative transition rates (AR), radiative lifetimes (τR), fluorescence branching ratios (βR) and the integrated absorption cross-section (∑) for stimulated emission from different excited states of Pr3+ ion. From the measured emission spectra, the principal fluorescence transitions of interest are identified and their stimulated emission cross-sections (σe) and branching ratios (βR) were determined. The measured branching ratios are in close agreement to the branching ratios predicted by the modified JO parameters. From these investigations, it is observed that the modified JO theory provides the positive values for the Ω2 parameters and also significant improvement between the measured and calculated oscillator strengths.