Thermal Management in AlGaAs-On-Insulator Microresonators: Enabling and Extending Soliton Comb Generation

Dissipative Kerr solitons offer a promising approach for integrated frequency comb sources. Although aluminum gallium arsenide (AlGaAs) exhibits ultrahigh nonlinearity, its strong thermo-optic effect raises significant challenges for stable soliton generation. Triggerring solitons necessitates either cryogenic cooling or resonator engineering, imposing stringent requirements on operational environments, comb spacing, and bandwidth. In this work, thermal management in AlGaAs-on-insulator microresonators is addressed using an auxiliary laser. This approach effectively suppresses the adverse thermal resonance shifts, thus enabling room-temperature soliton comb generation. Simultaneously, the residual thermal effects can be leveraged to expand the soliton existence range up to 37 GHz without active feedback. The scheme imposes no limitations on resonator parameters, facilitating the observation of near-zero-dispersion solitons. This broadens the exploration horizons on the AlGaAsOI platform. The extended soliton existence range ensures a stable and robust soliton operation, which is crucial for fully exploiting the ultra-high effective nonlinearity and high optical quality factors exhibited by this platform. This advancement is poised to accelerate the practical deployment of AlGaAs frequency comb sources.