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arXiv · 1403.8114

Motility versus fluctuations in mixtures of self-propelled and passive agents

Denis F. Hinz·Alexander Panchenko·Tae-Yeon Kim·Eliot Fried
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Abstract

Many biological systems consist of self-motile and passive agents both of which contribute to overall functionality. However, there are very few studies of the properties of such mixtures. Here we formulate a model for mixtures of self-motile and passive agents and show that the model gives rise to three different dynamical phases: a disordered mesoturbulent phase, a polar flocking phase, and a vortical phase characterized by large-scale counterrotating vortices. We use numerical simulations to construct a phase diagram and compare the statistical properties of the different phases of the model with self-motile bacterial suspensions. Our findings afford specific insights regarding the interaction of microorganisms and passive particles and provide novel strategic guidance for efficient technological realizations of artificial active matter.

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cond-mat.softphysics.bio-phphysics.comp-phphysics.flu-dyn

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Denis F. Hinz, Alexander Panchenko, Tae-Yeon Kim, Eliot Fried. 2014-03-31. Motility versus fluctuations in mixtures of self-propelled and passive agents. https://doi.org/10.1039/c4sm01562b

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