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arXiv · 1311.0638

Time asymmetry of the Kramers equation with nonlinear friction: fluctuation-dissipation relation and ratchet effect

A. Sarracino
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Abstract

We show by numerical simulations that the presence of nonlinear velocity-dependent friction forces can induce a finite net drift in the stochastic motion of a particle in contact with an equilibrium thermal bath and in an asymmetric periodic spatial potential. In particular, we study the Kramers equation for a particle subjected to Coulomb friction, namely a constant force acting in the direction opposite to the particle's velocity. We characterize the nonequilibrium irreversible dynamics by studying the generalized fluctuation-dissipation relation for this ratchet model driven by Coulomb friction.

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BibTeXRIS

A. Sarracino. 2013-11-19. Time asymmetry of the Kramers equation with nonlinear friction: fluctuation-dissipation relation and ratchet effect. https://doi.org/10.1103/physreve.88.052124

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