Sorting of chiral active particles by a spiral shaped obstacle

Abstract

Sorting of chiral particles by obstacles often relies on the chiral symmetry breaking of the patterns. We proposed a method for the chiral separation of chiral active particles in a two-dimensional square box where exists a spiral shaped obstacle. With the chirality of circular motion coupling to chiral features in the spiral environment, the mixed chiral particles can be separated and selectively trapped by the spiral shaped obstacle. We found that the mixed particles can be completely separated for the optimal angular speed and self-propulsion speed of active particles. Our results can be exploited to capture or sort chiral active particles with specific parameters.