Rotating cavity solitons in semiconductor microresonators.

We predict the existence of a ring-like localized solutions in wide aperture passive semiconductor quantum well microresonators. These dark ring cavity solitons exist for positive cavity detuning in a frequency range where nonlinear dispersive effects prevail against absorptive ones. As a rule, destabilization of these ring solitons leads to the formation of radial asymmetric rotating solitons in externally driven optical cavities.