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arXiv · 1910.06547

From scalar to polar active matter: Connecting simulations with mean-field theory

Ashreya Jayaram·Andreas Fischer·Thomas Speck
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Abstract

We study numerically the phase behavior of self-propelled elliptical particles interacting through the "hard" repulsive Gay-Berne potential at infinite P\'eclet number. Changing a single parameter, the aspect ratio, allows to continuously go from discoid active Brownian particles to elongated polar rods. Discoids show phase separation, which changes to a cluster state of polar domains, which then form polar bands as the aspect ratio is increased. From the simulations, we identify and extract the two effective parameters entering the mean-field description: the force imbalance coefficient and the effective coupling to the local polarization. These two coefficients are sufficient to obtain a complete and consistent picture, unifying the paradigms of scalar and polar active matter.

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BibTeXRIS

Ashreya Jayaram, Andreas Fischer, Thomas Speck. 2019-10-15. From scalar to polar active matter: Connecting simulations with mean-field theory. https://doi.org/10.1103/physreve.101.022602

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