Numerical demonstration of the existence of the long-lived localized state in the weakly nonlinear topological insulator. The figure shows the snapshot of the simulation at t = 1. The sites at the left edge show large amplitudes, which indicates the existence of the edge-localized state. The parameters used are u = -1 and = 0.1, and the average amplitude is w = 0.1, which corresponds to the blue circle in b.
