High-power, thermally accessible dissipative Kerr soliton generation

Kerr frequency combs, or microcombs, are revolutionizing fields such as precision metrology, optical clocks, and astronomical spectrometer calibration. However, conventional dissipative Kerr soliton (DKS) microcombs often suffer from limited conversion efficiency and low output power, and achieving deterministic single-soliton generation remains a challenge due to limited thermal accessibility arising from the intricate interplay of Kerr and thermal effects. In this work, we present an optimized microresonator design combined with a robust pumping scheme to enhance the thermal accessibility of single-soliton states for deterministic generation. By operating a silicon nitride microresonator with tailored dispersion in the over-coupled regime, we demonstrate a thermally accessible pathway to single solitons with high conversion efficiency (approaching 30%), and high output power (up to 50 mW). Through a pump forward-tuning process with power ramping, followed by backward tuning, we achieve deterministic single-soliton generation across 80 consecutive trials via automated laser tuning, eliminating the need for complex thermal compensation or rapid tuning schemes. Our work provides a straightforward and robust solution for generating high-power solitons, advancing the practicality and accessibility of microcombs for real-world applications.