Random-walk topological transition revealed via electron counting

Abstract

The appearance of topological effects in systems exhibiting non-trivial topological band structures strongly relies on the coherent wave nature of the equations of motion. Here, we reveal topological dynamics in a classical stochastic random walk version of the Su-Schrieffer-Heeger model with no relation to coherent wave dynamics. We explain that the commonly used topological invariant in the momentum space translates into an invariant in a counting field space. This quantization gives rise to clear signatures of the topological phase in an associated waiting time distribution.