Thermally induced generation of platicons in optical microresonators

We demonstrate a numerically novel mechanism providing generation of the flat-top solitonic pulses, platicons, in optical microresonators at normal group velocity dispersion (GVD) via negative thermal effects. We found that platicon excitation is possible if the ratio of the photon lifetime to the thermal relaxation time is large enough. We show that there are two regimes of the platicon generation depending on the pump amplitude: the smooth one and the oscillatory one. Parameter ranges providing platicon excitation are found and analyzed for different values of the thermal relaxation time, frequency scan rate, and GVD coefficient. Possibility of the turn-key generation regime is also shown.