Double-flattop half-vortices and self-bound solitary-wave billiards in cubic-quintic media with intermodal attraction
Phys. Rev. A 113, 013501 – Published 2 January, 2026
DOI: https://doi.org/10.1103/2bp1-15wn
Abstract
We consider a bimodal light field envelope propagating in a bulk medium characterized by competing cubic and quintic nonlinearities. The two components are coupled by a cross-phase-modulation term and experience effective attraction. We find dynamically stable stationary states which have two distinct flattop regions with different intensities. These solutions represent half-vortices, where the first and second components are essentially different and in particular carry different topological charges: zero for one component and nonzero for the other. The typical propagation of an unstable half-vortex leads to the splitting of the central vortex core into several fragments which quasielastically interact with the boundary of the flattop region. This behavior is interpreted as a self-bound solitary-wave billiard, where the emerging fragments are the billiard balls and the flattop region is the dynamically deforming table.
