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arXiv · 1308.6423

Cooperative Motion of Active Brownian Spheres in Three-Dimensional Dense Suspensions

Adam Wysocki·Roland G. Winkler·Gerhard Gompper
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Abstract

The structural and dynamical properties of suspensions of self-propelled Brownian particles of spherical shape are investigated in three spatial dimensions. Our simulations reveal a phase separation into a dilute and a dense phase, above a certain density and strength of self-propulsion. The packing fraction of the dense phase approaches random close packing at high activity, yet the system remains fluid. Although no alignment mechanism exists in this model, we find long-lived cooperative motion of the particles in the dense regime. This behavior is probably due to an interface-induced sorting process. Spatial displacement correlation functions are nearly scale-free for systems with densities close to or above the glass transition density of passive systems.

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Adam Wysocki, Roland G. Winkler, Gerhard Gompper. 2013-08-29. Cooperative Motion of Active Brownian Spheres in Three-Dimensional Dense Suspensions. https://doi.org/10.1209/0295-5075/105/48004

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