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arXiv · 2308.08419

Quantum walk in stochastic environment

Ben Avnit·Doron Cohen
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Abstract

We consider a quantized version of the Sinai-Derrida model for "random walk in random environment". The model is defined in terms of a Lindblad master equation. For a ring geometry (a chain with periodic boundary condition) it features a delocalization-transition as the bias in increased beyond a critical value, indicating that the relaxation becomes under-damped. Counter intuitively, the effective disorder is enhanced due to coherent hopping. We analyze in detail this enhancement and its dependence on the model parameters. The non-monotonic dependence of the Lindbladian spectrum on the rate of the coherent transitions is highlighted.

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Ben Avnit, Doron Cohen. 2023-08-16. Quantum walk in stochastic environment. https://doi.org/10.1103/physreve.108.054111

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