Time asymmetry of the Kramers equation with nonlinear friction: Fluctuationdissipation relation and ratchet effect
Abstract
We show by numerical simulations that the presence of nonlinear velocitydependent 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 fluctuationdissipation relation for this ratchet model driven by Coulomb friction.
 Publication:

Physical Review E
 Pub Date:
 November 2013
 DOI:
 10.1103/PhysRevE.88.052124
 arXiv:
 arXiv:1311.0638
 Bibcode:
 2013PhRvE..88e2124S
 Keywords:

 05.40.a;
 02.50.Ey;
 Fluctuation phenomena random processes noise and Brownian motion;
 Stochastic processes;
 Condensed Matter  Statistical Mechanics
 EPrint:
 6 pages, 4 figures