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arXiv · 1110.2479

Spontaneous Segregation of Self-Propelled Particles with Different Motilities

Samuel R. McCandlish·Aparna Baskaran·Michael F. Hagan
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Abstract

We study mixtures of self-propelled and passive rod-like particles in two dimensions using Brownian dynamics simulations. The simulations demonstrate that the two species spontaneously segregate to generate a rich array of dynamical domain structures whose properties depend on the propulsion velocity, density, and composition. In addition to presenting phase diagrams as a function of the system parameters, we investigate the mechanisms driving segregation. We show that the difference in collision frequencies between self-propelled and passive rods provides a driving force for segregation, which is amplified by the tendency of the self-propelled rods to swarm or cluster. Finally, both self-propelled and passive rods exhibit giant number fluctuations for sufficient propulsion velocities.

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Samuel R. McCandlish, Aparna Baskaran, Michael F. Hagan. 2011-10-11. Spontaneous Segregation of Self-Propelled Particles with Different Motilities. https://doi.org/10.1039/c2sm06960a

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