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arXiv · 1205.4511

Interaction-induced decoherence in non-Hermitian quantum walks of ultracold Bosons

K. Rapedius·H. J. Korsch
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Abstract

We study the influence of particle interaction on a quantum walk on a bipartite one-dimensional lattice with decay from every second site. The corresponding non-interacting (linear) system has been shown to have a topological transition described by the average displacement before decay. Here we use this topological quantity to distinguish coherent quantum dynamics from incoherent classical dynamics caused by a breaking of the translational symmetry. We furthermore analyze the behavior by means of a rate equation providing a quantitative description of the incoherent nonlinear dynamics.

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K. Rapedius, H. J. Korsch. 2012-05-21. Interaction-induced decoherence in non-Hermitian quantum walks of ultracold Bosons. https://doi.org/10.1103/physreva.86.025601

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