Paradoxical directed diffusion due to temperature anisotropiesR. Eichhorn and P. Reimann
Universität Bielefeld, Fakultät für Physik Universitätsstraße 25, 33615 Bielefeld, Germany
received 29 October 2004; accepted 14 December 2004
published online 14 January 2005
An analytically tractable, but still experimentally realistic model dynamics is investigated, describing the Brownian motion of a particle in a "meandering" periodic potential landscape under the simultaneous influence of two different heat baths. The main characteristics of the resulting far-from-equilibrium environment is an anisotropy of the ambient temperature. When an external static force F is applied, the particle moves in the direction opposite to that force (absolute negative mobility), and this even for arbitrarily large forces |F|. Moreover, even when the "meandering" potential exhibits a broken spatial symmetry, no preferential direction of motion arises for F=0.
05.40.-a - Fluctuation phenomena, random processes, noise, and Brownian motion.
05.60.-k - Transport processes.
02.50.Ey - Stochastic processes.
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