Optical features of novel fluorotellurite glasses based on TeO2- LiNbO3- BaF2- La2O3- (Nb2O5 or TiO2)

New families from fluorotellurite glasses with composition 7.53 TeO2-7.31 LiNbO3-4.16 Nb2O5-10 BaF2-1.0La2O3, 72.53 TeO2-7.31 LiNbO3-10 Nb2O5-10 BaF2-1.0La2O3 and 77.53 TeO2-7.31 LiNbO3-5 TiO2-10 BaF2-1.0La2O3 in mol% were prepared. The thermal characterization and optical properties of these glasses were estimated by using differential scanning calorimetric, DSC, and UV-vis-NIR spectroscopy respectively. The results of thermal analysis indicate that 77.53 TeO2-7.31 LiNbO3-5 TiO2-10 BaF2-1.0La2O3 glasses has high thermal stability and high factor against crystallization. The density and linear refractive index, n, of present glasses were measured. Also, the physical parameters such as; oxygen packing density, molar volumes, oxygen molar volume, molar refraction, metallization criterion, molar polarizability, third-order non-linear susceptibility and two photon absorption coefficients were calculated. It was found that, the linear refractive index increases otherwise decrease in the optical energy gap with increase Nb2O5 concentration. On the basis on thermal and optical results of these glasses it can be concluded that fluorotellurite glasses tested can be used in optical application.