Surface-mediated attraction between colloids

H Kaïdi (1) , Thomas Bickel (2) , M. Benhamou (1)

1 LPPPC - Laboratoire de Physique des Polymères et Phénomènes Critiques [Casablanca]
2 CPMOH - Centre de physique moléculaire optique et hertzienne

We investigate the equilibrium properties of a colloidal solution in contact with a soft interface. As a result of symmetry breaking, surface effects are generally prevailing in confined colloidal systems. In this Letter, particular emphasis is given to surface fluctuations and their consequences on the local (re)organization of the suspension. It is shown that particles experience a significant effective interaction in the vicinity of the interface. This potential of mean force is always attractive, with range controlled by the surface correlation length. We suggest that, under some circumstances, surface-induced attraction may have a strong influence on the local particle distribution.

Mots clés: colloids; membrane; potential of mean force; Classical statistical mechanics; Disperse systems Complex fluids; Membranes bilayers and vesicles

Domaines: Mécanique statistique [cond-mat.stat-mech]; Matière Molle [cond-mat.soft]

H Kaïdi, Thomas Bickel, M. Benhamou. Surface-mediated attraction between colloids. EPL - Europhysics Letters, 2005, 69 (1), pp.15-21. ⟨10.1209/epl/i2004-10305-4⟩. ⟨hal-00003204⟩