Ratchet transport powered by chiral active particles

TL;DR

This study numerically explores how chiral active particles induce directed ratchet transport in asymmetric channels, revealing mechanisms for particle separation and optimal conditions for transport efficiency.

Contribution

It demonstrates the role of particle chirality in controlling transport direction and efficiency, providing new insights into active matter ratchet systems.

Findings

Chirality determines the direction of active particle transport.

Passive particles exhibit complex transport behavior influenced by multiple factors.

Optimal parameters maximize rectified transport efficiency.

Abstract

We numerically investigate the ratchet transport of mixtures of active and passive particles in a transversal asymmetric channel.A big passive particle is immersed in a 'sea' of active particles. Due to the chirality of active particles, the longitudinal directed transport is induced by the transversal asymmetry. For the active particles, the chirality completely determines the direction of the ratchet transport, the counterclockwise and clockwise particles move to the opposite directions and can be separated. However, for the passive particle, the transport behavior becomes complicated, the direction is determined by competitions among the chirality, the self-propulsion speed, and the packing fraction. Interestingly, within certain parameters, the passive particle moves to the left,while active particles move to the right. In addition, there exist optimal parameters(the chirality, the height of the barrier, the self-propulsion speed and the packing fraction) at which the rectified efficiency takes its maximal value. Our findings could be used for the experimental pursuit of the ratchet transport powered by chiral active particles.