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arXiv · 1702.00656

Active Brownian particles at interfaces: An effective equilibrium approach

René Wittmann·Joseph M. Brader
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Abstract

A simple theoretical approach is used to investigate active colloids at the free interface and near repulsive substrates. We employ dynamical density functional theory to determine the steady-state density profiles in an effective equilibrium system [Farage et al., Phys. Rev. E, 91 (2015) 042310]. In addition to the known accumulation at surfaces, we predict wetting and drying transitions at a flat repulsive wall and capillary condensation and evaporation in a slit pore. These new phenomena are closely related to the motility-induced phase separation (MIPS) in the bulk.

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René Wittmann, Joseph M. Brader. 2017-02-02. Active Brownian particles at interfaces: An effective equilibrium approach. https://doi.org/10.1209/0295-5075/114/68004

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