12 research outputs found
Structure and Dynamics of a Phase-Separating Active Colloidal Fluid
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.Comment: 5 pages, 5 figure