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arXiv · 1311.1086

Tunable transport with broken space-time symmetries

Sergey Denisov·Sergej Flach·Peter Hanggi
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Abstract

Transport properties of particles and waves in spatially periodic structures that are driven by external time-dependent forces manifestly depend on the space-time symmetries of the corresponding equations of motion. A systematic analysis of these symmetries uncovers the conditions necessary for obtaining directed transport. In this work we give a unified introduction into the symmetry analysis and demonstrate its action on the motion in one-dimensional periodic, both in time and space, potentials. We further generalize the analysis to quasi-periodic drivings, higher space dimensions, and quantum dynamics. Recent experimental results on the transport of cold and ultracold atomic ensembles in ac-driven optical potentials are reviewed as illustrations of theoretical considerations.

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Sergey Denisov, Sergej Flach, Peter Hanggi. 2014-01-22. Tunable transport with broken space-time symmetries. https://doi.org/10.1016/j.physrep.2014.01.003

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