Regensburg 2007 – scientific programme

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DY: Fachverband Dynamik und Statistische Physik

DY 16: Brownian motion and transport I

DY 16.1: Talk

Tuesday, March 27, 2007, 14:30–14:45, H3

Dispersionless transport in a washboard potential — •Igor Sokolov — Institut für physik, Humboldt Universität zu Berlin

Based on extensive numerical simulations of thermally agitated classical particles in a tilted washboard potential we have identified and characterized a transport regime that involves dispersionless motion of particles over several decades of time in appropriate parameter regimes. This remarkably coherent behavior requires the presence of thermal fluctuations, and is restricted to underdamped systems. The associated distribution of the particle positions moves at an essentially constant velocity and is far from Gaussian. This new regime is complementary to, and entirely different from, well-known nonlinear response and large dispersion regimes observed for other values of the external force. We provide a theoretical framework to estimate the times of onset and duration of dispersionless transport and the parameter regimes in which it occurs. A similar regime is also observed in numerical simulations in two dimensions with a tilted separable potential. Our results may be testable on the motion of molecules and clusters on surfaces as well as in Josephson junctions.

K. Lindenberg, J. M. Sancho, A. M. Lacasta, and I. M. Sokolov, Phys. Rev. Lett., in press.