ABSTRACT
Generation and properties of dissipative Kerr solitons and platicons in optical microresonators are studied in the presence of the backscattering using the original analytical model considering a linear forward-backward waves coupling and nonlinear cross-action. We reveal that the backscattering may suppress the generation of the solitonic pulses or destabilize them for both anomalous and normal group velocity dispersion. We also demonstrate the possibility of switching between different soliton states. The influence of the linear and nonlinear coupling is analysed. It is shown that while the impact of the nonlinear coupling on the generation of the bright solitons is rather weak, it is significantly more pronounced for the platicon excitation process.
ABSTRACT
We generalize the coupled mode formalism to study the generation of frequency combs in microresonators with simultaneous Raman and Kerr nonlinearities and investigate an impact of the former on the formation of frequency combs and dynamics of platicons in the regime of the normal group velocity dispersion. We demonstrate that the Raman effect initiates generation of sidebands, which cascade further in four-wave mixing and reshape into the Raman-Kerr frequency combs. We reveal that the Raman scattering induces a strong instability of the platicon pulses associated with the Kerr effect and normal dispersion. This instability results in branching of platicons and complex spatiotemporal dynamics.
