Monolithic piezoelectric control of soliton microcombs

We demonstrate piezoelectric actuators monolithically integrated on ultralow-loss Si 3 N 4 waveguides. Varying the voltage applied on the actuator allows microresonator tuning, and to initiate, switch, stabilize and tightly phase lock the single soliton microcomb. This new capability allows to build a compact soliton-based paralell LiDAR.