TeO2-TiO2-Bi2O3系统玻璃的热学特性及光学带隙研究

采用熔融淬冷法制备了系列高折射率的TeO2-TiO2-Bi2O3系统玻璃,测试了样品的密度、转变温度、析晶温度、折射率、吸收光谱,利用经典的Tauc方程计算了样品光学带隙允许的直接跃迁、允许的间接跃迁及Urbach能量.讨论了玻璃的热稳定性与组成之间的关系、研究了摩尔折射度、金属标准值、光学带隙、Urbach能量、Bi2O3和TiO2含量及光学碱度对玻璃样品折射率的影响.结果表明TeO2-TiO2-Bi2O3玻璃具有较好的热稳定性、样品的折射率随着摩尔折射度增大而增大,而光学带隙及金属标准值有减小的趋势,此外高的光学碱度对玻璃的高的三阶非线性也有一定的贡献.

Thermal Characteristics and Optical Band Gap Properties of TeO2-TiO2-Bi2O3 Glasses

A series of TeO2-TiO2-Bi2O3 glasses were prepared by using conventional melting and quenching method. Their densities, transition temperatures, crystallization temperatures, refractive indices, absorption spectra were measured. The allowed direct transition and indirect transition, and Urbach energy of samples were calculated according to classical Tauc equation. The relationships between thermal stability and glass compositions were discussed. The effects of molar refraction、 metallization criterion, optical band gap, Urbach energy, contents of TiO2 and Bi2O3, and optical basicity on refractive indices of glass samples were also discussed . The results show that the TeO2-TiO2-Bi2O3 glass system has good stability. With the increase of molar refraction the refractive index increases, optical band gap and metallization criterion shrink. Meanwhile, the high third-order non linearity is associated with high optical basicity.