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arXiv · 1611.01054

Phase behavior of active Brownian disks, spheres, and dumbbells

Jonathan Tammo Siebert·Janina Letz·Thomas Speck·Peter Virnau
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Abstract

In this paper we provide high precision estimates of the phase diagram of active Brownian particles. We extract coexisting densities from simulations of phase separated states in an elongated box (slab geometry) which minimizes finite-size effects and allows for precise determination of points on the binodal lines. Using this method, we study the influence of both shape and dimensionality on the two-phase region. Active spheres and dumbbells of active particles are compared to the known phase diagram of active Brownian disks. In the case of dimers, both correlated and uncorrelated propulsion of the two beads are studied. The influence of correlation is discussed through a simple mapping.

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Jonathan Tammo Siebert, Janina Letz, Thomas Speck, Peter Virnau. 2016-11-03. Phase behavior of active Brownian disks, spheres, and dumbbells. https://doi.org/10.1039/c6sm02622b

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