Hydrodynamic coupling of two brownian spheres to a planar surface.
نویسندگان
چکیده
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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عنوان ژورنال:
- Physical review letters
دوره 85 15 شماره
صفحات -
تاریخ انتشار 2000