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arXiv · 1109.2707

Hydrodynamic Pair Attractions Between Driven Colloidal Particles

Yulia Sokolov·Derek Frydel·David G. Grier·Haim Diamant·Yael Roichman
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Abstract

Colloidal spheres driven through water along a circular path by an optical ring trap display unexpected dynamical correlations. We use Stokesian Dynamics simulations and a simple analytical model to demonstrate that the path's curvature breaks the symmetry of the two-body hydrodynamic interaction, resulting in particle pairing. The influence of this effective nonequilibrium attraction diminishes as either the temperature or the stiffness of the radial confinement increases. We find a well defined set of dynamically paired states whose stability relies on hydrodynamic coupling in curving trajectories.

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Yulia Sokolov, Derek Frydel, David G. Grier, Haim Diamant, Yael Roichman. 2011-09-13. Hydrodynamic Pair Attractions Between Driven Colloidal Particles. https://doi.org/10.1103/physrevlett.107.158302

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