Physical, Optical and Structural Properties of Er3+ Doped Zinc/Cadmium Bismuth Borate/Silicate Glasses

Glasses with compositions 20MO·xBi₂O₃·(79.5-x)B₂O₃ (15 ≤ x ≤ 35, x in mol%,) and 20MO·xSiO₂·(79.5-x)Bi₂O₃ (10 ≤ x ≤ 50, x in mol%, M = Zn and Cd) containing 0.5 mol% Er³⁺ ions were prepared by normal melt-quench technique (1150°C in air). The effect of host glass composition on the optical absorption and fluorescence spectra of Er³⁺ ions have been observed with varying contents of Bi₂O₃. Judd-Ofelt approach has been applied for f-f transition of Er³⁺ ions to evaluate various intensity parameters viz. Ω_λ (λ = 2, 4, 6). The variation of Ω₂ with Bi₂O₃ content has been attributed to change in the asymmetry of ligand field at the rare earth ion site. The Judd-Ofelt intensity parameters were determined from intensities of absorption bands in order to calculate the radiative properties viz. transition probability (A_rad), and radiative life-time of the excited states (τ_r). From the emission spectra, full width at half maxima (FWHM), stimulated emission crosssection (σ) and figure of merit were evaluated and compared with other hosts. The observed NIR emission (⁴I_13/2→⁴I_15/2 at 1.5μm) in Er³⁺-doped zinc/cadmium bismuth borate/ silicate glasses may be useful in optical communication.

Keywords: Rare-earth ions, Rare-earth doped glasses, Laser Glasses, Oxide glasses, Heavy-metal oxide glasses, Judd-Ofelt theory, Optical material, Optical transition, Absorption spectra, Fluorescence spectra, Physical properties of glasses, FTIR, Radiative transition probability, Radiative lifetime, Stimulated emission crosssection, Figure of merit, Intensity parameters, Melt-quech technique, Matrix elements, Er³⁺ doped glasses.