Hydrodynamic coupling of two brownian spheres to a planar surface.
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.
Dufresne
E R
ER
Department of Physics, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA.
Squires
T M
TM
Brenner
M P
MP
Grier
D G
DG
D003102:Colloids / Q000737:chemistry*; D004058:Diffusion; D008956:Models, Chemical; D012822:Silicon Dioxide / Q000737:chemistry; D013499:Surface Properties
D003102:Colloids; D012822:Silicon Dioxide