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arXiv · 2005.06893

Motility-Induced Microphase and Macrophase Separation in a Two-Dimensional Active Brownian Particle System

Claudio B. Caporusso·Pasquale Digregorio·Demian Levis·Leticia F. Cugliandolo·Giuseppe Gonnella
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Abstract

As a result of nonequilibrium forces, purely repulsive self-propelled particles undergo macrophase separation between a dense and a dilute phase. We present a thorough study of the ordering kinetics of such motility-induced phase separation (MIPS) in active Brownian particles in two dimensions, and we show that it is generically accompanied by microphase separation. The growth of the dense phase follows a law akin to the one of liquid-gas phase separation. However, it is made of a mosaic of hexatic microdomains whose size does not coarsen indefinitely, leaving behind a network of extended topological defects from which microscopic dilute bubbles arise. The characteristic length of these finite-size structures increases with activity, independently of the choice of initial conditions.

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BibTeXRIS

Claudio B. Caporusso, Pasquale Digregorio, Demian Levis, Leticia F. Cugliandolo, Giuseppe Gonnella. 2020-05-14. Motility-Induced Microphase and Macrophase Separation in a Two-Dimensional Active Brownian Particle System. https://doi.org/10.1103/physrevlett.125.178004

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