Hybrid ${\rm As}_{2}{\rm S}_{3}$ Mach-Zehnder Interferometer Prepared by Magnetron Sputtering and its Photodarkening Effect

Several hybrid integrated As₂S₃ Mach-Zehnder interferometers with linear tapers and grating couplers have been successfully fabricated using magnetron sputtering on LiNbO₃ substrate. It demonstrated how As₂S₃ waveguide can be integrated with the LiNbO₃ waveguide to create a hybrid interferometer for use in chalcogenide photonics. The photo-induced changes in the group and effective index of the As₂S₃ waveguide were measured and compared to values reported for films prepared by thermal evaporation. These photo-induced phenomena are found to be different from those reported for As₂S₃ bulk glass and thermally evaporated As₂S₃ film.