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Weak Long-Ranged Casimir Attraction in Colloidal Crystals

Ajay Gopinathan·Tong Zhou·S. N. Coppersmith·L. P. Kadanoff·David G. Grier
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Abstract

We investigate the influence of geometric confinement on the free energy of an idealized model for charge-stabilized colloidal suspensions. The mean-field Poisson-Boltzmann formulation for this system predicts pure repulsion among macroionic colloidal spheres. Fluctuations in the simple ions' distribution provide a mechanism for the macroions to attract each other at large separations. Although this Casimir interaction is long-ranged, it is too weak to influence colloidal crystals' dynamics.

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Ajay Gopinathan, Tong Zhou, S. N. Coppersmith, L. P. Kadanoff, David G. Grier. 2001-07-12. Weak Long-Ranged Casimir Attraction in Colloidal Crystals. https://doi.org/10.1209/epl%2Fi2002-00481-1

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