Narrowband gain in chalcogenide waveguides for low-power RF delay lines

In this paper we present high stimulated Brillouin scattering (SBS) gain in a chip-scale device. Narrowband gain of >50 dB is achieved in a chalcogenide waveguide with a bandwidth of ∼10 MHz. Such a large gain is promising for on-chip amplification for the realization of integrated structures with many optical components, as well as for RF photonic and optical signal processing applications. We harness the highly efficient SBS interaction in the photonic chip to realize low-power RF filters, phase shifters and delay lines. Through the concept of RF interference an enhancement in the delay by almost a factor of 6 compared to pure SBS-based slow light is observed, making this technology promising for lowpower-budget RF photonic systems.The authors acknowledge funding by the Australian Research Council (ARC) for the DECRA Fellowship (DE170100585, DE150101535), Laureate Fellowship (FL120100029), and the CUDOS Center of Excellence (CE110001018) and the U.S. Department of the Air Force through AFOSR/AOARD (grant # FA2386-16-1-4036). K.V, P.M, and S.M acknowledge the ACT node of the Australian National Fabrication Facility (ANFF)