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arXiv · 0903.2736

Directing Brownian motion on a periodic surface

D. Speer·R. Eichhorn·P. Reimann
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Abstract

We consider an overdamped Brownian particle, exposed to a two-dimensional, square lattice potential and a rectangular ac-drive. Depending on the driving amplitude, the linear response to a weak dc-force along a lattice symmetry axis consist in a mobility in basically any direction. In particular, motion exactly opposite to the applied dc-force may arise. Upon changing the angle of the dc-force relatively to the square lattice, the particle motion remains predominantly opposite to the dc-force. The basic physical mechanism consists in a spontaneous symmetry breaking of the unbiased deterministic particle dynamics.

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D. Speer, R. Eichhorn, P. Reimann. 2009-03-16. Directing Brownian motion on a periodic surface. https://doi.org/10.1103/physrevlett.102.124101

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