Minimal model of active colloids highlights the role of mechanical interactions in controlling the emergent behavior of active matter

• Published in: Current opinion in colloid & interface science Vol. 21; pp. 34 - 43
• Main Authors: Marchetti, M. Cristina, Fily, Yaouen, Henkes, Silke, Patch, Adam, Yllanes, David
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.02.2016
• Subjects: Active glasses; Active matter; colloids; gases; mechanical properties; Phase separation; separation; Swim pressure; Swim pressure; Active glasses; Active matter; Phase separation
• ISSN: 1359-0294; 1879-0399
• DOI: 10.1016/j.cocis.2016.01.003

Minimal models of active Brownian colloids consisting of self-propelled spherical particles with purely repulsive interactions have recently been identified as excellent quantitative testing grounds for theories of active matter and have been the subject of extensive numerical and analytical investigation. These systems do not exhibit aligned or flocking states but do have a rich phase diagram, forming active gases, liquids, and solids with novel mechanical properties. This article reviews recent advances in the understanding of such models, including the description of the active gas and its swim pressure, the motility-induced phase separation and the high-density crystalline and glassy behavior. [Display omitted] •Describe minimal model of active colloids.•Discuss the behavior of active gasses, emphasizing the role of stress and, in particular, of the swim pressure.•Discuss the motility-induced phase separation in active fluids.•Discuss the physics of active glasses and active solids and their jamming dynamics.