Events in Physics

Living Cluster in Suspensions of Active Colloids

Active colloids are interesting in view of their unique collective behaviours and because of their relevance in modelling biological systems like the cytoskeleton or the bacterial motility. Recent experiments have shown that self-propelled particles assemble into finite aggregates that merge and split, but have a typical size that remains constant (living clusters). In this contribution we numerically investigate living clusters in suspensions of driven colloids. We use two different systems: self-propelled particles interacting via a generic attractive potential and colloids that can self-displace themselves towards each others by molecular motors. In both cases we rationalise the formation of living clusters in terms of a competition between active forces and thermodynamic equilibrium. When mixed with passive particles self-displacing colloids can also assemble into open aggregates.