Coexistence of bright and dark cavity solitons in microresonators with zero, normal, and anomalous group-velocity dispersion: a switching wave approach

We propose a theoretical study to analyze how both dark and bright Kerr solitons can be generated in whispering-gallery mode resonators with various regimes of the group-velocity dispersion, namely normal, anomalous, and null. The coexistence of these solitonic structures in each regime is shown to appear around a critical value of the laser pump. We also evidence that these solitons build up owing to a mechanism related to oscillation locking of switching waves, which connect the upper and the lower homogenous steady states.