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arXiv · 1812.09050

Continuous-time random walk for a particle in a periodic potential

Andreas Dechant·Farina Kindermann·Artur Widera·Eric Lutz
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Abstract

Continuous-time random walks offer powerful coarse-grained descriptions of transport processes. We here microscopically derive such a model for a Brownian particle diffusing in a deep periodic potential. We determine both the waiting-time and the jump-length distributions in terms of the parameters of the system, from which we analytically deduce the non-Gaussian characteristic function. We apply this continuous-time random walk model to characterize the underdamped diffusion of single Cesium atoms in a one-dimensional optical lattice. We observe excellent agreement between experimental and theoretical characteristic functions, without any free parameter.

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Andreas Dechant, Farina Kindermann, Artur Widera, Eric Lutz. 2018-12-21. Continuous-time random walk for a particle in a periodic potential. https://doi.org/10.1103/physrevlett.123.070602

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