Multiple soliton regimes enabled by parametric down-conversion in $χ^{(2)}+χ^{(3)}$ microresonators

Half-harmonic generation in microresonators with mixed $χ^{(2)}$ and $χ^{(3)}$ nonlinearities provides access to a rich landscape of two-colour soliton states and frequency combs. We numerically demonstrate the formation of both bright and topological two-colour solitons at relatively modest pump po