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arXiv · 1108.3439

Collective dynamics of colloids at fluid interfaces

J. Bleibel·A. Dominguez·M. Oettel·S. Dietrich
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Abstract

The evolution of an initially prepared distribution of micron sized colloidal particles, trapped at a fluid interface and under the action of their mutual capillary attraction, is analyzed by using Brownian dynamics simulations. At a separation λ given by the capillary length of typically 1 mm, the distance dependence of this attraction exhibits a crossover from a logarithmic decay, formally analogous to two-dimensional gravity, to an exponential decay. We discuss in detail the adaption of a particle-mesh algorithm, as used in cosmological simulations to study structure formation due to gravitational collapse, to the present colloidal problem. These simulations confirm the predictions, as far as available, of a mean-field theory developed previously for this problem. The evolution is monitored by quantitative characteristics which are particularly sensitive to the formation of highly inhomogeneous structures. Upon increasing λ the dynamics show a smooth transition from the spinodal decomposition expected for a simple fluid with short-ranged attraction to the self-gravitational collapse scenario.

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J. Bleibel, A. Dominguez, M. Oettel, S. Dietrich. 2011-10-27. Collective dynamics of colloids at fluid interfaces. https://doi.org/10.1140/epje/i2011-11125-5

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