Zero-dispersion solitons in microresonators with octave-spanning dispersive wave formation

Kerr microresonator frequency comb generation has been concerned mostly with the formation of bright dissipative solitons [1] , pulses existing continuously in driven microresonators having anomalous group-velocity dispersion (GVD). Alternatively in resonators having normal GVD, optical switching waves are able to exist [2] , state-flips between the two CW solutions of the optically bistable Kerr cavity. Here, we report the creation of a novel localised structure, the zero-dispersion soliton (ZDS) [3] , that embodies a hybrid between dissipative solitons and switching waves, physically relating the two to each other. They are found to exist in the regime of (nearly) vanishing GVD, where instead third-order dispersion (TOD) is dominant. The ZDS can be thought of as two switching waves able to lock together, through the interaction of a dispersive wave (DW), forming a solitary bright pulse structure that contains multiple quantized peaks.