Research Progress on Full Stabilization Techniques for Soliton Microcombs

To explore the development of high-integration, fully stabilized microcavity optical frequency combs with promising applications in chip-scale quantum metrology standards, recent advancements have demonstrated that dissipative Kerr soliton-based microcombs are well-suited for time-frequency metrology, length metrology, and precision spectroscopy. However, due to the limitations in maintaining long-term stability under external perturbations, free-running soliton microcombs face challenges in practicality and reliability. Achieving a fully phase-locked soliton microcomb is thus essential for chip-scale quantum metrology standards. This research provides an overview of the locking techniques for various degrees of freedom in soliton microcombs, including pump frequency, repetition frequency, and carrier-envelope-offset frequency. In addition, a brief review is provided on full stabilization techniques based on the above three locking methods and their applications in optical metrology. Finally, challenges facing full-stabilization technology for soliton microcombs and future development are discussed.