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Effective forces between colloids at interfaces induced by capillary wave-like fluctuations

H. Lehle·M. Oettel·S. Dietrich
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Abstract

We calculate the effective force mediated by thermally excited capillary waves between spherical or disklike colloids trapped at a fluid interface. This Casimir type interaction is shown to depend sensitively on the boundary conditions imposed at the three-phase contact line. For large distances between the colloids an unexpected cancellation of attractive and repulsive contributions is observed leading to a fluctuation force which decays algebraically very rapidly. For small separations the resulting force is rather strong and it may play an important role in two-dimensional colloid aggregation if direct van der Waals forces are weak.

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H. Lehle, M. Oettel, S. Dietrich. 2006-08-23. Effective forces between colloids at interfaces induced by capillary wave-like fluctuations. https://doi.org/10.1209/epl%2Fi2006-10065-1

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