Two-line-seeded dark-soliton microcomb cloning dynamics in normal-dispersion microresonators

Area of Science:

• Photonics
• Nonlinear optics
• Soliton physics

Background:

• Optical microcombs generate phase-correlated wavelength grids for parallel photonic systems.
• Drift between independent microcomb sources degrades comb-line alignment, hindering applications requiring matched or synchronized combs.

Purpose of the Study:

• To numerically investigate the two-line-seeded cloning of normal-dispersion dark-soliton microcombs.
• To assess the impact of free-spectral-range mismatch on cloned microcombs.
• To explore methods for improving the stability and existence range of cloned dark-soliton microcombs.

Main Methods:

• Numerical simulations using the Lugiato-Lefever equations.
• Generation of a transmitter dark-soliton microcomb via localized pump-mode resonance perturbation.
• Regeneration of a receiver dark-soliton microcomb using the transmitter's pump and μ = -1 comb lines as a two-line seed.

Main Results:

• Free-spectral-range mismatch leads to temporal walk-off, spectral asymmetry, and reduced receiver soliton existence range.
• Independent control of seed-line powers expanded the receiver soliton existence range from ~15 MHz to >1 GHz in the matched case.
• A near-GHz best accessible soliton existence range was maintained over tested mismatches, though the high-performance operating area narrowed.

Conclusions:

• Two-line-seeded cloning is a viable method for regenerating dark-soliton microcombs.
• Independent control of seed-line powers is critical for overcoming spectral mismatch issues and enhancing the robustness of cloned microcombs.
• This technique offers a pathway to improved synchronization and stability in parallel photonic systems.