Comparative study of Dy3+ doped borate glasses on the basis of luminescence and lasing properties for white-light generation

In this work, a comparative study of Dy3+ activated NMgBiBDy and NBaBiBDy glasses is carried out by investigating the luminescence and lasing properties for the application of white-light generation. By using absorption spectra the oscillator strengths [experimental (fexp) and calculated (fcal)] are measured. The small stimulated emission crossection (sigma rms) values show that they are in good agreement with literature as well as confirm the JO theory. The JO intensity parameters confirm the high asymmetry and the covalence around Dy3+ in the titled glasses. The luminescence emission spectra are carried out by fixing the excitation wavelengths at 388 and 453 nm for NBaBiBDy and NMgBiBDy glasses, respectively. The quenching point is determined at 1.0 mol% for both glasses. The asymmetry nature is confirmed by the yellow/blue (Y/B) ratio. By using the luminescence emission spectra, the important Judd Ofelt (JO) parameters [AR, beta rad, o lambda eff, sigma(lambda p)] are measured. The decay time shows decreasing behavior, confirming the resonance and cross-relaxation energy process in the samples. From the decay times data (tau exp, tau cal) the quantum efficiency and non-radiative relaxation for 4F9/2 level are determined. The chromaticity results suggest that these glasses can be exploited for white-light generation. The NMgBiBDy1.0 glass exhibits better luminescence and lasing properties than the NBaBiBDy1.0, promising for laser and whitelight generation.