The effect of SiO₂ content on structural, physical and spectroscopic properties of Er^3 + doped B₂O₃–SiO₂–Na₂O–PbO–ZnO glass systems

Er^3 + doped borosilicate glasses were prepared by standard method with the chemical composition (50 − x) B₂O₃–(10 + x) SiO₂–10 Na₂O–20 PbO–10 ZnO–0.3 Er₂O₃ (where x = 0, 5, 10, 15, 20, 25, 30, 35, 40). The prepared glass samples were characterized by XRD, EDAX, FTIR, SEM and TEM. XRD reveals the amorphous nature of the glass samples. Various band positions are confirmed by the FTIR and borate network is present in the wavelength region 650–1700 cm^− 1. Elemental composition of the glass samples were observed by EDAX. Variation of physical and optical parameters with increasing concentration of SiO₂ affects the glass structure. Decrease in the value of Oxygen Packing Density (OPD) with increasing concentration of SiO₂ shows loosely packed structure of glass samples. Absorption and fluorescence spectra were recorded in Visible and NIR region at room temperature. Judd–Ofelt (JO) intensity parameters were calculated by using oscillator strength and the order of these parameters is Ω₂ > Ω₄ > Ω₆. Radiative properties were obtained by JO parameters and fluorescence spectra. A bright green emission is observed for the transition ²H_11/2, ⁴S_3/2 → ⁴I_15/2 and it is further confirmed by Commission Internationale de l’ Eclairage (CIE) chromaticity diagram. ²H_11/2, ⁴S_3/2 → ⁴I_15/2 is suitable for green lasers. This gives the suitability of the present glass sample for fibre optics amplifier and photonic application.