Interpretation of the crossover stability regime

Determine whether the cavity soliton in the most stable region of the saturable-absorber cavity model is best interpreted as a trapped switching wave, a local nonlinear resonance, or a combination of both.

Background

For the saturable-absorber cavity soliton, the paper analyzes perturbation eigenmodes across the stable intensity range. At lower powers, a localized eigenmode supports the local nonlinear resonance interpretation, whereas near the upper stability boundary, other eigenmodes resemble trapped switching waves.

Around the point where these modes cross over, the authors cannot decide which physical interpretation is correct. This leaves unresolved the characterization of the cavity soliton’s nature in the most stable operating region.

References

For applications, one might want to work in the most stable region, where the two modes cross over. At that point, the correct interpretation is far from clear: trapped switching wave? local nonlinear resonance? a bit of both?

— Cavity Solitons  (2608.26985 - Firth et al., 27 Aug 2026) in Section “Stationary Solutions and Stability,” discussion following Fig. 6