Structural and luminescent investigation of Eu³⁺ doped lead borosilicate glasses

Lead borosilicate (LBS) glasses incorporated with europium (Eu³⁺) ions were synthesized using various chemical constituents. The structure of the glass matrix has been studied by experimental techniques such as X-ray diffraction (XRD), Fourier transform infrared (FTIR), optical absorption (OA) and photoluminescence (PL) spectroscopy. From the XRD spectrum, several crystalline phases of LBS glass host were identified. The FTIR spectrum of the LBS glass host was recorded to investigate the local structural and functional groups. Due to the different characteristic nature of the Eu³⁺ ion, the absorption bands were observed from the ground (⁷F₀) and the first excited (⁷F₁) states. Further, Judd-Ofelt theory has been applied to compute the intensity parameters (Ω_λ, λ = 2, 4 and 6) from the absorption intensities of ⁷F₀ → ⁵D₂ and ⁷F₀ → ⁵L₆ transitions, respectively. Characteristic emission bands are observed at 578, 592, 613,653 and 701 nm corresponding to ⁵D₀ → ⁷F₀, ⁷F₁, ⁷F₂, ⁷F₃ and ⁷F₄ transitions, respectively. The radiative and laser characteristic parameters like stimulated emission cross-section (σ_e) and branching ratios (β_R) of the ⁵D₀ excited level are computed. From the magnitude of stimulated emission cross-section (σ_e) and branching ratios (β_R) obtained for ⁵D₀ → ⁷F² transition revealed that, Eu³⁺: LBS glasses are suitable for good laser action in the visible region.