Blog

Title: “Collective behaviour in chemically interacting active particles”

Abstract: Systems of chemically interacting active colloids are a paradigmatic system of interest in active matter. Here, we report novel collective behaviour in systems of chain composed by linking up these colloids. These chains, interacting via chemicals deposited from their centers, display a wide range of phenomenology from frustration to correlated large-scale motion to global polarity depending on the aspect ratio, activity parameters, and packing fraction of the system. Moreover, we show that in systems consisting of non-reciprocally interacting constituent units, appropriately designed chains may give rise to a behaviour such as undulatory gaits, reversal of motion, and chirality. These “chiral foldamers” have a straightforwardly tunable rotational frequency, suggesting a simple paradigm for targeted tuning of colloidal dynamics. Collections of monomers display a first-order Vicsek-like transition to a flocking state. Moreover, treating the above chain as a non-equilibrium interface, we report new exponents for the height fluctuations.