Red solitons: evidence of spatiotemporal instability in chi 2 spatial soliton dynamics

In chi(2) three-wave mixing, the noise-seeded spatiotemporal modulational instability has a dramatic impact on the spatial soliton formation and on their stability, leading to the occurrence of a temporal breakup on the 20 fs scale and to the counterintuitive observation of spatial solitons with no apparent participation of the high-frequency field in the self-trapping.