Ratchetlike devices can rectify symmetric, unbiased nonequilibrium noise resulting in fluctuation-induced currents. We study some simple models to investigate the dependence of a nonequilibrium steady-state current on the characteristic features of the ratchet and the applied noise. It turns out that the magnitude and the direction of the induced current depend not only on the shape of the ratchet, but also on the statistics of the fluctuations.

• Received 8 November 1993

DOI:https://doi.org/10.1103/PhysRevLett.72.2984