Structural, Thermal, and Optical Properties of GeO₂-La₂O₃-TiO₂ Glasses

La 2 O 3 -TiO 2 glasses show promising application prospect in fields of lenses, optical windows, and optical communication, owing to their high refractive index and excellent performance.However, this glass cannot be prepared into large size because of its weak glass forming ability, which seriously limits its application.In this study, introducing the network former GeO 2 can effectively improve the glass forming ability, so that large-sized GeO 2 -La 2 O 3 -TiO 2 (GLT) glass can be prepared using conventional methods.Differential thermal analysis shows that GLT glasses have high glass transition temperature (T g ) and strong resistance to precipitation, with T g and T (T c-onset -T g ) greater than 833 and 209 , respectively.The refractive index is up to 2.06.The transmittance can reach 78% in the visible and near-infrared wavelength bands.The glass forming ability and thermal stability can be weakened by increasing the content of TiO 2 .The molar volume and oxygen electron polarizability exhibit the same variation trends as the refractive index of the samples.This result is important for developing new devices with high performance, light weight, and small size.