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arXiv · 1707.06096

Random-walk topological transition revealed via electron counting

G. Engelhardt·M. Benito·G. Platero·G. Schaller·T. Brandes
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Abstract

The appearance of topological effects in systems exhibiting a non-trivial topological band structure 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 invariant gives rise to clear signatures of the topological phase in an associated escape time distribution.

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G. Engelhardt, M. Benito, G. Platero, G. Schaller, T. Brandes. 2018-03-07. Random-walk topological transition revealed via electron counting. https://doi.org/10.1103/physrevb.96.241404

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