Spectroscopic and photoluminescence properties of Dy3+-doped lead tungsten tellurite glasses for laser materials

Lead tungsten tellurite (LTT) glasses doped with different Dy3+ ion concentrations have been prepared and characterized through optical absorption, photoluminescence and decay measurements. The glassy nature of the LTT host has been confirmed through the XRD measurements. The three phenomelogical intensity parameters Ωλ (λ = 2, 4, 6) have been determined from the absorption spectral intensities using the Judd–Ofelt (J–O) theory. The hypersensitivity of 6H15/2 → 6F11/2 transition based on the magnitude of Ω2 parameter has also been discussed. By using the J–O intensity parameters several radiative properties such as spontaneous transition probabilities (AR), fluorescence branching ratios (βR) and radiative lifetimes (τR) have been determined. The effect of Dy3+ ion concentration on the emission intensities of 4F9/2 → 6HJ′ (J′ = 15/2, 13/2, 11/2 and 9/2) transitions has also been reported.

Research highlights▶ Dy–O covalency increases with increase of yellow-to-blue intensity ratio. ▶ Interaction among Dy3+ ions at higher concentrations causes fluorescence quenching. ▶ Role of energy transfer at higher concentrations results in a decrease in lifetimes. ▶ LTTDy glasses can be used as color displaying devices and optical amplifiers.