A mean-field (Gross-Pitaevskii) study, in a periodically modulated optical lattice, of how interaction/nonlinearity strength reshapes the topological (Thouless-type) pumping of edge solitons. Four regimes emerge: weak nonlinearity preserves near-linear bidirectional adiabatic edge transport; moderate nonlinearity breaks spectral symmetry and creates self-crossings that destroy the right-to-left channel, leaving only left-to-right pumping; strong nonlinearity breaks single-cycle pumping but enables hybridized edge-and-bulk soliton transport over multiple cycles; still stronger nonlinearity self-traps the soliton and shuts all pumping channels. The work maps the interplay between nonlinear dynamics and topological phase.
We study how nonlinear strength affects topological pumping of edge solitons by using nonlinear Gross-Pitaevskii equation. For weak nonlinear strength, the introduction of nonlinearity breaks the sym…