Kinetics of motility-induced phase separation and swim pressure

Adam Patch, David Yllanes, M Cristina Marchetti

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Active Brownian particles (ABPs) represent a minimal model of active matter consisting of self-propelled spheres with purely repulsive interactions and rotational noise. Here we examine the pressure of ABPs in two dimensions in both closed boxes and systems with periodic boundary conditions and show that its nonmonotonic behavior with density is a general property of ABPs and is not the result of finite-size effects. We correlate the time evolution of the mean pressure towards its steady-state value with the kinetics of motility-induced phase separation. For parameter values corresponding to phase-separated steady states, we identify two dynamical regimes. The pressure grows monotonically in time during the initial regime of rapid cluster formation, overshooting its steady-state value and then quickly relaxing to it, and remains constant during the subsequent slower period of cluster coalescence and coarsening. The overshoot is a distinctive feature of active systems.

Original languageEnglish (US)
Article number012601
JournalPhysical Review E - Statistical, Nonlinear, and Soft Matter Physics
Volume95
Issue number1
DOIs
StatePublished - Jan 5 2017

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Motility
locomotion
Phase Separation
Kinetics
kinetics
Cluster Formation
Finite Size Effects
Overshoot
Minimal Model
Coalescence
Coarsening
Periodic Boundary Conditions
Correlate
coalescing
boxes
Two Dimensions
boundary conditions
Closed
Interaction
interactions

ASJC Scopus subject areas

  • Statistical and Nonlinear Physics
  • Statistics and Probability
  • Condensed Matter Physics

Cite this

Kinetics of motility-induced phase separation and swim pressure. / Patch, Adam; Yllanes, David; Marchetti, M Cristina.

In: Physical Review E - Statistical, Nonlinear, and Soft Matter Physics, Vol. 95, No. 1, 012601, 05.01.2017.

Research output: Contribution to journalArticle

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