Concentration-dependence and luminescence studies of erbium doped barium lithium fluoroborate glasses

Abstract

The present spectral investigations on erbium doped barium lithium fluoroborate glasses of the composition (70-x) H3BO3 − 10 Li2CO3 − 10 BaCO3 − 5 CaF2 − 5 ZnO − x Er2O3 (where x = 0.05, 0.1, 0.5, 1, 2 in wt %) were prepared by the conventional melt quenching technique. Dielectric constant, refractive index, electronic susceptibility, reflection loss and interionic distance were calculated for all the glass samples. The X-ray diffraction spectrum confirmed the amorphous nature of the prepared glasses. The optical properties of the prepared glasses were investigated by UV–Vis-NIR absorption and emission spectra. Nephelauxetic ratio and bonding parameters were determined from the absorption spectra and are found to be covalent in nature. Optical bandgap corresponding to the direct and indirect allowed transition were calculated to understand the electronic band structure and the Urbach energy values. Judd-Ofelt (JO) intensity parameters (Ωλ = 2, 4 and 6) were determined from the absorption spectrum. These JO parameters were used to analyse the transition probability (A), branching ratio (βR), and the stimulated emission cross section (σPE) parameter for different emission intensities. The emission of infrared at 1550 nm indicates that the glass material can act as a promising wave guide laser source and is suitable in optical fiber amplifier applications.