We explored the structure and physical properties of Ge₁₅Sb₂₀Se_65-xS_x (with x = 0, 16.25, 32.5, 48.75, and 65) glasses in order to screen the best compositions for the applications in photonics, since the laser damage thresholds in Se-based glasses are too low although their optical nonlinearities are high. We found that, linear and nonlinear refractive index of the glasses decreased, but glass transition temperature T_g, optical bandgap E_g and the laser damage threshold increased with increasing S content. We further employed Raman scattering and high-resolution X-ray photoelectron spectra to probe the structure of the glasses. Through the analysis of the evolution of the different structural units in the glasses, it was concluded that, the heteropolar bonds (Ge–Se/S, Sb–Se/S) were dominated in these glasses. With the increase in chalcogen Se/S ratio, the number of the Se-related chemical bonds (Ge–Se, Sb–Se and Se–Se) increased and that of S-related chemical bond (Ge–S, Sb–S and S–S) decreased gradually, and Ge was prior to bond with S rather than Se. The elemental substitution thus had negligible effect on the glass structure. The change of the physical properties was mainly due to the difference of the strength of the chemical bonds between S–Ge(Sb) and Se–Ge(Sb).

中文翻译：

---

Ge15Sb20Se65-xSx玻璃的结构和物理性质

我们探索了Ge ₁₅ Sb ₂₀ Se _{65- x} S _x（x = 0、16.25、32.5、48.75和65）玻璃的结构和物理性质，以便筛选出适用于光子学的最佳成分，因为激光硒基玻璃的损伤阈值过低，尽管它们的光学非线性很高。我们发现，玻璃的线性和非线性折射率降低，但是玻璃化转变温度T _g，光学带隙E _g随着S含量的增加，激光损伤阈值增加。我们进一步采用拉曼散射和高分辨率X射线光电子能谱来探测眼镜的结构。通过分析玻璃中不同结构单元的演变，可以得出结论，这些玻璃中的杂极性键（Ge-Se / S，Sb-Se / S）占主导。随着硫族元素硫/硫比的增加，硒相关化学键（Ge–Se，Sb–Se和Se–Se）的数量增加，而硫相关化学键（Ge–S，Sb–S和S–S）逐渐降低，Ge在与S而不是与Se结合之前。因此，元素取代对玻璃结构的影响可忽略不计。物理性质的变化主要是由于S–Ge（Sb）和Se–Ge（Sb）之间化学键的强度不同所致。