Chalcogenide optical waveguides with extremely high stimulated brillouin scattering gain for integrated devices

This paper reports on the fabrication details and performance of chalcogenide waveguides consisted of a ridge geometry 2.2-2.6μm wide on a silica substrate with different film thickness (550-950nm) and etching depth (30-50%). A silica cladding layer was also used to improve acoustic confinement compared to previous designs using polymer claddings. Spiral waveguides formed on a 2cm wide chip, with up to 24cm long spirals used in the experiments. The propagation loss of these waveguides were around 0.2dB/cm. Highest on-chip SBS gain of up to 47dB in this As 2 S 3 waveguide platform is reported. This extremely high level of SBS gain means that much better applications can be realized