Multicolor emission in potassium-zinc phosphate glasses activated with Dy3+, Tb3+ and Dy3+/ Tb3+ for photonic device applications

We report the spectroscopy analysis of potassium zinc phosphate glasses activated with Dy3+, Tb3+ and Dy3+/Tb3+. Radiative parameter values (stimulated emission cross section, effective bandwidth, gain bandwidth and optical gain) were obtained for the dysprosium 4F9/2 → 6H15/2 and 4F9/2 → 6H13/2 emissions upon 349 nm excitation. Emission of warm white light can be attained in the KZDy glass upon excitation at 349 nm. The co-doped glass can emit yellowish-green light from Tb3+ and Dy3+ luminescence sensitized by Dy3+ (upon 394 nm excitation) and Tb3+ (upon 377 nm excitation), respectively. The Dy3+ to Tb3+ energy transfer efficiency is higher (38.5%) than that (22.7%) of the Tb3+ to Dy3+ energy transfer.