GeO2 activated tellurite tungstate glass: A new candidate for solid state lasers and fiber devices

Different amounts of GeO2 activated tellurite tungstate glasses were prepared by melt quenching technique. Thermal stability and glass forming ability were studied using differential scanning calorimetry. The chemical composition, homogeneity and amorphous nature of studied glasses were investigated. The phonon energy was estimated to be 721.34 cm(-1). Experimentally determined refractive indices were compared with those determined from optical band gap (E-g) and optical electronegativity (Delta chi*). The dielectric constant (K) and electronic polarizability (alpha) were determined using refractive index value. The presence of disorder was estimated in terms of Urbach energy (E-U). The average electronegativity (chi(ave)), oxide ion polarizability (ao(2-)) and covalent character (C-cov) were determined. The content of GeO2 was optimized to be 10.0 mol% to design a novel host material for solid state lasers and fiber devices.