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arXiv · 1801.08790

Isotropic-nematic transition of self-propelled rods in three dimensions

Matthias C. Bott·Felix Winterhalter·Matthieu Marechal·Abhinav Sharma·Joseph M. Brader·René Wittmann
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Abstract

Using overdamped Brownian dynamics simulations we investigate the isotropic-nematic (IN) transition of self-propelled rods in three spatial dimensions. For two well-known model systems (Gay-Berne potential and hard spherocylinders) we find that turning on activity moves to higher densities the phase boundary separating an isotropic phase from a (nonpolar) nematic phase. This active IN phase boundary is distinct from the boundary between isotropic and polar-cluster states previously reported in two-dimensional simulation studies and, unlike the latter, is not sensitive to the system size. We thus identify a generic feature of anisotropic active particles in three dimensions.

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Matthias C. Bott, Felix Winterhalter, Matthieu Marechal, Abhinav Sharma, Joseph M. Brader, René Wittmann. 2018-01-26. Isotropic-nematic transition of self-propelled rods in three dimensions. https://doi.org/10.1103/physreve.98.012601

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