Optical, emission, and excitation dynamics of Eu³⁺ -doped bismuth-based phosphate glass for visible display laser applications

Eu³⁺ -doped-bismuth-based phosphate glasses with chemical equation (60 - x)P₂ O₅ -20Bi₂ O₃ -10Na₂ CO₃ -10SrF₂ -xEu₂ O₃ (PBNSEu), (where x = 0, 0.1, 0.5, 1.0, 1.5 and 2 mol%) were fabricated using the melt-quenching method. Obtain X-ray diffraction (XRD), energy-dispersive X-ray (EDAX), and Fourier transform infrared (FTIR) spectra were used to characterize the structure of the prepared PBNSEu glass. The J-O (Judd-Ofelt) intensity parameters (Ω₂ , Ω₄ ) were estimated using photoluminescence emission spectra. When excited with a xenon lamp at λ_exc = 394 nm, the most intense red-emission transition occurred at ~612 nm (⁵ D₀ →⁷ F₂ ). J-O intensity parameters were used to calculate radiative properties, whereas the radiative branching ratio (β_R ), radiative transition probability (A_R ), radiative lifetime (τ_R ), and total radiative transition rate (A_τ ) were calculated for the transitions ⁵ D₀ →⁷ F_J (where J = 0-4) and were obtained in the emission spectra for europium ion-doped in the current glass. Using the CIE1931 chromaticity coordinates axes, the colours of various concentrations of Eu³⁺ ion-doped PBNS glass were evaluated using the emission spectra. Temperature-dependent luminescence spectra were recorded for the optimized PBNSEu20 glass to calculate the activation energy. These results strongly suggested red components in w-LEDs and visible display laser applications.