Stimulated Brillouin laser-based carrier recovery in a high-Q microcavity for coherent detection

We demonstrate all-optical carrier recovery exploring a stimulated Brillouin laser (SBL) in a high-Q whispering-gallery-mode microcavity, to achieve coherent data detection without requiring an independent local oscillator laser. An ultra-high optical signal-to-noise ratio better than 70 dB is achieved for the recovered carrier, thanks to the fact that the generated SBL counter-propagates with the incoming data signal and experiences high SBS efficiency. High-frequency stability is obtained between the recovered carrier tone and the original data signal, enabling high-performance coherent detection without the need of electrical frequency drift compensation. This Letter offers a low complexity, high energy efficiency, and high robust carrier recovery solution.