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arXiv · 2003.14350

Current inversion in a periodically driven two-dimensional Brownian ratchet

Nils E. Strand·Rueih-Sheng Fu·Todd R. Gingrich
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Abstract

It is well-known that Brownian ratchets can exhibit current reversals, wherein the sign of the current switches as a function of the driving frequency. We introduce a spatial discretization of such a two-dimensional Brownian ratchet to enable spectral methods that efficiently compute those currents. These discrete-space models provide a convenient way to study the Markovian dynamics conditioned upon generating particular values of the currents. By studying such conditioned processes, we demonstrate that low-frequency negative values of current arise from typical events and high-frequency positive values of current arises from rare events. We demonstrate how these observations can inform the sculpting of time-dependent potential landscapes with a specific frequency response.

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Nils E. Strand, Rueih-Sheng Fu, Todd R. Gingrich. 2020-03-31. Current inversion in a periodically driven two-dimensional Brownian ratchet. https://doi.org/10.1103/physreve.102.012141

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