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Hydrodynamic Coupling of Two Brownian Spheres to a Planar Surface

Eric R. Dufresne·Todd M. Squires·Michael P. Brenner·David G. Grier
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Abstract

We describe direct imaging measurements of the collective and relative diffusion of two colloidal spheres near a flat plate. The bounding surface modifies the spheres' dynamics, even at separations of tens of radii. This behavior is captured by a stokeslet analysis of fluid flow driven by the spheres' and wall's no-slip boundary conditions. In particular, this analysis reveals surprising asymmetry in the normal modes for pair diffusion near a flat surface.

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Eric R. Dufresne, Todd M. Squires, Michael P. Brenner, David G. Grier. 2000-03-20. Hydrodynamic Coupling of Two Brownian Spheres to a Planar Surface. https://doi.org/10.1103/physrevlett.85.3317

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