Solitons and Propagating Domain Walls in Topological Resonator Arrays

An array of linear resonators with alternating linear-nonlinear bonds can transition from a topologically trivial to a nontrivial band structure as a function of the applied intensity. Here, we demonstrate that edge modes supported by the topology of the band diagram in such arrays can evolve into solitons, sustained by propagating domain walls induced by the local intensity distribution. The character of the nonlinear response is related to intensity-induced topological transitions in band theory, and it can be successfully captured by a continuum model. Our findings open up opportunities for self-reconfigurable topologically protected signal transport in various wave systems from optics to acoustics.