Numerical investigations of cavity-soliton distillation in Kerr resonators using the nonlinear Fourier transform

Dissipative cavity solitons (CSs) in a Kerr resonator have wide applications from optical communications to spectroscopy due to their broad bandwidth. Although the broadband spectrum ultrashort pulses are easy to be generated in a high-Q microresonator, such kinds of solitons in the macroscopic fiber ring resonator are difficult to be obtained. Dispersion management can be a feasible method to realize soliton compression, but the Kelly-like sidebands in the frequency domain are increased inside the cavity. To achieve a perfect soliton from a macroscopic cavity, an ingenious method of nonlinear Fourier transform (NFT) is utilized here to filter out the sidebands. The CS is mapped to different components in the nonlinear spectrum and a pure soliton can be reconstructed from the resonant continuous-wave background accordingly. Numerical simulations demonstrate NFT can be an effective method for CS analysis both in the time and frequency domains. Our investigations exemplify another application of NFT in a dissipative nonlinear system.