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Screened hydrodynamic interaction in a narrow channel

Bianxiao Cui·Haim Diamant·Binhua Lin
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Abstract

We study experimentally and theoretically the hydrodynamic coupling between Brownian colloidal particles diffusing along a linear channel. The quasi-one-dimensional confinement, unlike other constrained geometries, leads to a sharply screened interaction. Consequently, particles move in concert only when their mutual distance is smaller than the channel width, and two-body interactions remain dominant up to high particle densities. The coupling in a cylindrical channel is predicted to reverse sign at a certain distance, yet this unusual effect is too small to be currently detectable.

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Bianxiao Cui, Haim Diamant, Binhua Lin. 2002-10-20. Screened hydrodynamic interaction in a narrow channel. https://doi.org/10.1103/physrevlett.89.188302

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