Lasing potentialities and white light generation capabilities of Dy3+ doped oxy-fluoroborate glasses

Oxy-fluoroborate (OFB) glasses doped with different concentrations of Dy3+ ions were synthesized through melt quenching technique and characterized by using optical absorption, photoluminescence and decay analysis to understand the lasing potentialities and their utility for white light emitting diodes (LEDs). The XRD spectrum recorded for undoped OFB glass confirms the amorphous nature of the prepared glasses. Judd-Ofelt theory has been applied to the recorded absorption spectra to measure the radiative properties such as transition probability (AR), radiative lifetimes (τR), branching ratios (βR) and spectroscopic quality factor (χ) for the prominent fluorescent levels. The emission spectra recorded for these glasses gives four emission transitions 4F9/2→6H15/2, 6H13/2, 6H11/2 and 6H9/2 for which effective band widths (ΔλP), experimental branching ratios (βexp) and stimulated emission cross-sections (σse) are evaluated. To know the lasing potentialities of these glasses, the quantum efficiency (η) of these glasses are measured by recording the decay curves for the prominent emission levels 4F9/2→6H15/2 and 4F9/2→6H13/2. Among the observed emission transitions, a transition at 575 nm (4F9/2→6H13/2) indicates the lasing potentialities. The CIE chromaticity co-ordinates and the confocal photoluminescence images of these glasses further suggests the near white light generation capabilities in principle.