Abstract: The present application relates to a mid-infrared (MIR) optical frequency comb (OFC) generation system and method based on manipulation of the multi-photon absorption (MPA) effect, which can break through the repetition-rate limitation for traditional systems and restricted bandwidth as well as high dependence on high-performance pump sources for microcavity-based frequency combs. The system includes a pump light source unit for providing a pump laser, a microring resonator (MRR) unit for broadband comb generation through nonlinear four-wave-mixing process, and an MPA effect control unit for realizing the MIR soliton-state OFC by controlling the loaded voltage or current on the MRR unit. The proposed system and operation method have advantages of being simple in structure, economic for use, and easy to implement for broadband low-noise frequency comb generation.

Abstract: A system for generating a mid-infrared optical frequency comb based on a lithium niobate microcavity includes pumping units, a beam combining unit, a nonlinear frequency conversion unit and a filtering unit. The pumping units are divided into two paths and are configured to provide two paths of pumping light. The beam combining unit is configured to perform beam combination on the two paths of pumping light The nonlinear frequency conversion unit is configured to receive the beam-combined pumping light and undergo a nonlinear four-wave mixing process to generate a broadband optical frequency comb at a mid-infrared waveband. The filtering unit is configured to filter the remaining pumping light and output a mid-infrared optical frequency comb.