Frequency selection by soliton excitation in nondegenerate intracavity down-conversion

We show that soliton excitation in intracavity down-conversion naturally selects a strictly defined frequency difference between the signal and idler fields. In particular, this phenomenon implies that if the signal has smaller losses than the idler then its frequency is pulled away from the cavity resonance and the idler frequency is pulled towards the resonance and vice versa. The frequency selection is shown to be closely linked with the relative energy balance between the idler and signal fields.