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arXiv · 1008.2783

Transport driven by biharmonic forces: impact of correlated thermal noise

Abstract

We study an inertial Brownian particle moving in a symmetric periodic substrate, driven by a zero-mean biharmonic force and correlated thermal noise. The Brownian motion is described in terms of a Generalized Langevin Equation with an exponentially correlated Gaussian noise term, obeying the fluctuation-dissipation theorem. We analyse impact of non-zero correlation time of thermal noise on transport properties of the Brownian particle. We identify regimes where the increase of the correlation time intensifies long-time transport of the Brownian particle. The opposite effect is also found: longer correlation time reduces the stationary velocity of the particle. The correlation time induced multiple current reversal is detected. We reveal that thermal noise of non-zero correlation time can radically enhance long-time velocity of the Brownian particle in regimes where in the white noise limit the velocity is extremely small. All transport properties can be tested in the setup consisting of a resistively and capacitively shunted Josephson junction device.

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BibTeXRIS

Lukasz Machura, Jerzy Luczka. 2010-08-16. Transport driven by biharmonic forces: impact of correlated thermal noise. https://doi.org/10.1103/physreve.82.031133

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