Novel Dynamical Features of Chiral Active Particles in Crowded Lattices

Active matter can convert ambient free energy into mechanical work at individual constituent level, giving rise to intriguing phenomena that far from equilibrium systems. On the one hand, chirality is ubiquitous in active matter; many biological and even synthetic active particles exhibit circular locomotion. On the other hand, a better understanding of how chiral active matter interact with complex environments can facilitate the applications of active matter. To this end, we perform particle-based simulations to investigate the transport properties of chiral active particles (CAPs) in a complex, crowded environment. Specifically, we use active Brownian dynamics to simulate CAPs self-propelling within a lattice of hard cylindrical obstacles. By tuning particle chirality and obstacle density, we identify a super-diffusion regime in which the CAPs become sensitive to the lattice configuration. We further study the transport of CAPs when subjected to a global flow. We predict a reentrant directional locking effect in that CAPs of high activities are directionally locked. As such, we demonstrate several novel dynamical features of CAPs that are not found in achiral active particles, paving the way towards designing chirality-based tools for single-cell diagnosis and separation.