https://doi.org/10.1140/epjst/e2013-02029-4
Regular Article
How entropy and hydrodynamics cooperate in rectifying particle transport
1 Department of Physics, Humboldt-Universität zu Berlin, Newtonstr. 15, 12489 Berlin, Germany
2 Department of Physics, Universität Augsburg, Universitätsstr. 1, 86135 Augsburg, Germany
a e-mail: steffen.martens@physik.hu-berlin.de
Received: 16 July 2013
Revised: 13 August 2013
Published online: 28 October 2013
Using the analytical Fick-Jacobs approximation formalism and extensive Brownian dynamics simulations we study particle transport through two-dimensional periodic channels with triangularly shaped walls. Directed motion is caused by the interplay of constant bias acting along the channel axis and a pressure-driven flow. In particular, we analyze the particle mobility and the effective diffusion coefficient. The mechanisms of entropic rectification is revealed in channels with a broken spatial reflection symmetry in presence of hydrodynamically enforced entropic trapping. Due to the combined action of the forcing and the pressure-driven flow field, efficient rectification with a drastically reduced diffusivity is achieved.
© EDP Sciences, Springer-Verlag, 2013
