Giant enhancement of hydrodynamically enforced entropic trapping in thin channels

Abstract

Using our generalized Fick-Jacobs approach [Martens et al., PRL 110, 010601 (2013); Martens et al., Eur. Phys. J. Spec. Topics 222, 2453-2463 (2013)] and extensive Brownian dynamics simulations, we study particle transport through three-dimensional periodic channels of different height. Directed motion is caused by the interplay of constant bias acting along the channel axis and a pressure-driven flow. The tremendous change of the flow profile shape in channel direction with the channel height is reflected in a crucial dependence of the mean particle velocity and the effective diffusion coefficient on the channel height. In particular, we observe a giant suppression of the effective diffusivity in thin channels; four orders of magnitude compared to the bulk value.

16 pages, 8 figures

References in corpus (12)

• Artificial Brownian motors: Controlling transport on the nanoscale
• Entropic transport: Kinetics, scaling and control mechanisms
• Periodic and Quasiperiodic Motion of an Elongated Microswimmer in Poiseuille Flow
• Entropic particle transport: higher order corrections to the Fick-Jacobs diffusion equation
• Entropic particle transport in periodic channels
• Permeability of porous materials determined from the Euler characteristic
• Hydrodynamically enforced entropic trapping of Brownian particles
• Brownian transport in corrugated channels with inertia
• Local characterization of hindered Brownian motion by using digital video microscopy and 3D particle tracking
• Optimizing the Performance of the Entropic Splitter for Particle Separation
• Accumulating Particles at the Boundaries of a Laminar Flow
• Impact of inertia on biased Brownian transport in confined geometries