Nonergodic Diffusion of Single Atoms in a Periodic Potential
Abstract
Diffusion is a central phenomenon in almost all fields of natural science revealing microscopic processes from the observation of macroscopic dynamics. Here, we consider the paradigmatic system of a single atom diffusing in a periodic potential. We engineer microscopic particle-environment interaction to control the ensuing diffusion over a broad range of diffusion constants and from normal to subdiffusion. While one- and two-point properties extracted from single particle trajectories, such as variance or position correlations, indicate apparent Brownian motion, the step size distribution, however, shows exponentially decaying tails. Furthermore non-ergodic dynamics is observed on long time scales. We demonstrate excellent agreement with a model of continuous time random walk with exponential distribution, which applies to various transport phenomena in condensed or soft matter with periodic potentials.
Keywords
Cite
@article{arxiv.1601.06663,
title = {Nonergodic Diffusion of Single Atoms in a Periodic Potential},
author = {Farina Kindermann and Andreas Dechant and Michael Hohmann and Tobias Lausch and Daniel Mayer and Felix Schmidt and Eric Lutz and Artur Widera},
journal= {arXiv preprint arXiv:1601.06663},
year = {2017}
}