Hydrodynamically enforced entropic trapping of Brownian particles

TL;DR

This paper investigates how combined force fields influence Brownian particle transport in corrugated channels, revealing conditions where hydrodynamic effects cause significant entropic trapping and diffusion suppression.

Contribution

It introduces a generalized Fick-Jacobs model incorporating hydrodynamic effects and demonstrates hydrodynamically enforced entropic trapping in complex force environments.

Findings

Hydrodynamic effects can significantly suppress particle diffusion.

A generalized Fick-Jacobs approach effectively describes particle transport.

Hydrodynamically enforced trapping occurs under specific force parameters.

Abstract

We study the transport of Brownian particles through a corrugated channel caused by a force field containing curl-free (scalar potential) and divergence-free (vector potential) parts. We develop a generalized Fick-Jacobs approach leading to an effective one-dimensional description involving the potential of mean force. As an application, the interplay of a pressure-driven flow and an oppositely oriented constant bias is considered. We show that for certain parameters, the particle diffusion is significantly suppressed via the property of hyrodynamically enforced entropic particle trapping.