Intense yellow luminescence from Dy3+-doped TeO2–WO3–GeO2 glasses: structural and optical characterization

Abstract

Different concentrations of Dy3+-doped oxyfluoride tellurite (TWGDy) glasses of composition (85 − x) TeO2 + 5 WO3 + 10 GeO2 + x DyF3, where x = 0, 0.1, 0.5, 1.0 and 2.0 mol% were prepared by melt quenching method. The Judd–Ofelt theory was applied to study the luminescence properties. Three phenomenological Judd–Ofelt (Ωλ=2,4,6) intensity parameters were obtained as Ω2 = 4.90 × 10−20 cm2, Ω4 = 1.73 × 10−20 cm2 and Ω6 = 1.48 × 10−20 cm2 for 0.5 mol% of Dy3+-doped TWGDy glass. When excited at different wavelengths, the TWGDy glasses exhibit three emission bands due to 4F9/2 → 6H15/2 (blue), 4F9/2 → 6H13/2 (yellow) and 4F9/2 → 6H11/2 (red) transitions. The excitation wavelength was optimized as 453 nm for strong and proficient luminescence from TWGDy glasses. Beyond 0.5 mol% of Dy3+ concentration, the TWGDy glasses show luminescence quenching. The laser characteristic parameters such as effective bandwidth, stimulated emission cross-section, gain bandwidth and optical gain were determined using the emission spectra and radiative parameters. The 0.5 mol% of Dy3+-doped TWGDy glass could be potential to design a new class of yellow laser material.