Optical transitions in Dy3+-doped magnesium zinc sulfophosphate glass

Dy3+-doped magnesium zinc sulfophosphate glasses with composition of (60 − x)P2O5-20MgO-20ZnSO4-xDy2O3 (x = 0.0, 0.5, 1.0, 1.5 and 2.0 mol%) were synthesized using melt-quenching technique and characterized via emission and absorption measurements. The UV-Vis-NIR absorption spectra in the wavelength range of 320-2000 nm revealed eleven absorption peaks which were assigned to the transitions from the ground level (6H15/2) to several excited energy levels of Dy3 + ion. The Judd-Ofelt (JO) intensity parameters (Ω2, Ω4, and Ω6) were evaluated to predict the radiative properties including transition probability, radiative lifetime, and branching ratios. Emission spectra of the prepared glass under 452 nm (6H15/2 → 4I15/2) excitation wavelength consisted of four bands centered at 480, 574, 662 and 752 nm which were originated from 4F9/2 → 6HJ (J = 15/2, 13/2, 11/2 and 9/2) transitions. Emission spectra were further used to determine the effective bandwidth, the stimulated emission cross-section, and branching ratios.