Optical and thermal stability of Ge-as-Se chalcogenide glasses for femtosecond laser writing

Chemically stoichiometric chalcogenide glasses of xGeSe2-(100-x)As2Se3 (x = 0, 20, 40, 60, 80) have been synthesized by using the melt-quenching method, and their optical and thermal stability for femtosecond laser writing have been investigated. It was found that, glass transition temperature increases while thermal expansion coefficient decreases with increasing Ge contents. The laser-induced damage threshold under 800 nm and 4.0 μm fs laser irradiation was also investigated. They are 183.8 and 323.97 mJ/cm2 at 800 nm and 4.0 μm for 80GeSe2-20As2Se3, being 1.61 and 2.02 times higher than the sizes of As2Se3 glasses, respectively. The introduction of Ge can significantly improve the optical and thermal stability of Ge-As-Se glasses that are promising in the application of high-stability photonic device prepared by femtosecond laser writing.