Figure 4. Robustness of the zero mode against structural disorder.

(a) Schematic representation of the randomized coupling strengths t₁, t₂ used in the experiments. The disorder strength W (red bar) is chosen to preserve the topological structure of the chain (t₁>t₂). (b) Zero-mode intensity profiles (normalized to 1) on A sites for the disordered chain without losses for different values of W. The grey-shaded curve follows the exponential profile . (c) Intensity profiles in the presence of losses on the B-sites. The grey-shaded curve is obtained for an effective coupling ratio . The topologically induced interface state is seen to be robust against the structural disorder, both with and without absorption.