Relation among optical, thermal and thermo-optical properties and niobium concentration in tellurite glasses

In this work, optical, thermal, thermo-optical and spectroscopic properties of the 80TeO2-(20 − x)Li2O-xNb2O5 (x = 5, 10 and 15 mol%) glasses were investigated by using the thermal lens spectrometry, X-Ray diffraction, Raman spectroscopy, modulated differential scanning calorimetry and Brewster angle method. The influence of Nb2O5 in the glass structure was interpreted by the thermal diffusivity, specific heat, thermal conductivity, temperature coefficient of the optical path length, refractive index and band gap energy. The calculated optical basicity and polarizability allowed bettering understanding the obtained results, reinforcing the assumption on the glass structural change.