Abstract: Kerr soliton frequency combs have emerged as a key technology for chip-scale optical atomic clock. However, the intracavity power drop during Kerr soliton formation leads to the cavity frequency drift, which limits the lifetime of the frequency combs. Some active control methods have been reported such as power control, PDH frequency locking, and auxiliary laser mode. But the control systems used for these methods are rarely reported. This work presents an FPGA-based active control system for stabilizing Kerr soliton frequency combs. It can stabilize the Kerr soliton combs in both MgF? and CaF? microresonators by the power control and PDH frequency locking methods. This system can be uesd for other platforms (e.g., Si?N?, AlN, SiO?) for Kerr soliton generation and stabilization.

Key words: Kerr soliton comb, active control, FPGA