Luminescence studies of Dy3+ doped bismuth zinc borate glasses

Glasses having composition of (100−x) (1Bi2O3-1ZnO-1B2O3)-xDy2O3 (where x=0.1, 0.3, 0.5, 1 and 2 mol%) were prepared by melt quenching method and characterized through optical absorption, emission and decay curve measurements. Optical absorption spectra have been analyzed using Judd-Ofelt theory. Asymmetric ratio, the intensity ratio of yellow to blue transitions, has been calculated from the emission spectra to understand the symmetry around the Dy3+ ions in the glass matrix. The emission spectra have been analyzed in the framework of CIE 1931 chromaticity colour coordinates in order to find out the white light emission characteristics of the glasses. The decay curve measurements exhibit single exponential behaviour up to 1 mol% of Dy3+ ions whereas non exponential behaviour is observed for 2 mol% of Dy3+ ions. The non exponential curve has been fitted to the Inokuti-Hirayama model to understand the nature of energy transfer process.