2020/05/31 by Claudio B. Caporusso, Pasquale Digregorio, Demian Levis +2 · 1 citation
Physics and Astronomy · #cond-mat.stat-mech #cond-mat.soft
paper · pdf · doi:10.1103/physrevlett.125.178004
published as Phys. Rev. Lett. 125, 178004 (2020) · 5 pages, 5 figures, SM
arxiv created 2021/09/08 · arxiv updated 2021/09/09
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.