Hidden Symmetries, Instabilities, and Current Suppression in Brownian Ratchets

作者:Cubero David*; Renzoni Ferruccio
来源:Physical Review Letters, 2016, 116(1): 010602.
DOI:10.1103/PhysRevLett.116.010602

摘要

The operation of Brownian motors is usually described in terms of out-of-equilibrium and symmetry-breaking settings, with the relevant spatiotemporal symmetries identified from the analysis of the equations of motion for the system at hand. When the appropriate conditions are satisfied, symmetry-related trajectories with opposite current are thought to balance each other, yielding suppression of transport. The direction of the current can be precisely controlled around these symmetry points by finely tuning the driving parameters. Here we demonstrate, by studying a prototypical Brownian ratchet system, the existence of hidden symmetries, which escape identification by the standard symmetry analysis, and which require different theoretical tools for their revelation. Furthermore, we show that system instabilities may lead to spontaneous symmetry breaking with unexpected generation of directed transport.

  • 出版日期2016-1-7