Program-controlled single soliton microcomb source

Soliton microcombs (SMCs) are spontaneously formed in a coherently pumped high-quality microresonator, which provides a new tool for use as an on-chip frequency comb for applications of high-precision metrology and spectroscopy. However, generation of SMCs seriously relies on advanced experimental techniques from professional scientists. Here, we experimentally demonstrate a program-controlled single SMC source where the intracavity thermal effect is timely balanced using an auxiliary laser during single SMC generation. The microcomb power is adopted as the criteria for microcomb states discrimination and a forward and backward thermal tuning technique is employed for the deterministic single SMC generation. Further, based on a closed-loop control system, the repetition rate stability of the SMC source improved more than 20 times and the pump frequency can be continuously tuned by simply changing the operation temperature. The reliability of the SMC source is verified by consecutive 200 generation trials and maintaining over 10 h. We believe the proposed SMC source will have significant promising influences in future SMC-based application development. (C) 2020 Chinese Laser Press

Automated summary

Soliton microcombs (SMCs) are spontaneously formed in high-quality microresonators, providing a new tool for on-chip frequency comb applications. The experimental demonstration of a program-controlled single SMC source shows the timely balancing of intracavity thermal effects using an auxiliary laser, leading to deterministic single SMC generation. The proposed SMC source shows improved repetition rate stability and continuous pump frequency tuning.