Structure and Dynamics of a Phase-Separating Active Colloidal Fluid

2012/07/31 by Gabriel S. Redner, Michael F. Hagan, Aparna Baskaran · 3 citations
Physics and Astronomy · #cond-mat.soft #physics.bio-ph

paper · pdf · doi:10.1016/j.bpj.2012.11.3534

published as Phys. Rev. Lett. 110, 055701 (2013) · 5 pages, 5 figures

arxiv created 2013/07/29 · arxiv updated 2017/08/23

Abstract

We examine a minimal model for an active colloidal fluid in the form of self-propelled Brownian hard spheres that interact purely through excluded volume. Despite the absence of an aligning interaction, this system shows the signature behaviors of an active fluid, including anomalous number fluctuations and phase separation behavior. Using simulations and analytic modeling, we quantify the phase diagram and separation kinetics. The dense phase is a unique material that we call an active hexatic, which exhibits the structural signatures of a crystalline solid near the crystal-hexatic transition point, but the rheological and transport properties associated with a viscoelastic fluid.

Cited by

• Self-alignment and anti-self-alignment suppress motility-induced phase separation in active systems
• Active Cahn-Hilliard theory for nonequilibrium phase separation: quantitative macroscopic predictions and a microscopic derivation
• Activity drives self-assembly of passive soft inclusions in active nematics
• Competing effect of disorder on phase separation in active systems