Luminescence properties of Dy3+ doped zinc–aluminum–sodium–phosphate (ZANP) glasses for white light applications

Abstract

The structural and optical properties of trivalent dysprosium (Dy3+)-doped zinc– aluminum–sodium–phosphate (ZANP) glasses have been investigated using XRD, FTIR, absorption, emission spectra and decay curve. The XRD profiles and SEM images confirm the glassy nature of the investigated glass samples. FTIR spectra reveal the presence of PO4 units along with OH− groups in the glasses. The absorption spectra of Dy3+ showed eight absorption bands with hypersensitive at 1272nm (6H15/2→6F11/2) and three PL emission bands at 485nm (4F9/2→6H15/2), 576nm, (4F9/2→6H13/2) and 665nm (4F9/2→6F11/2). The luminescence intensity ratio of 4F9/2→6H13/2 to 4F9/2→6H15/2 transitions of Dy3+ in ZANP glasses gives feasibility of extracting white light. The experimental branching ratios and stimulated emission cross-sections are higher for 4F9/2→6H13/2 transition. The lifetime of the decay is obtained by taking the first e-folding times of the decay curves and is found to decrease with increase of Dy3+ ions concentration. The decay curves are found to be perfectly single exponential for samples upto1.5mol% Dy3+ ion concentrations. The non-exponential curve is obtained at 2.0mol% of Dy3+ ion concentration, which indicates the energy transfer between the donor and acceptor.