Manipulating chiral microswimmers in a channel.

We numerically simulate the diffusion of overdampd pointlike Janus particles along narrow two-dimensional periodically corrugated channels with reflecting walls. The self-propulsion velocity of the particle is assumed to rotate subject to an intrinsic bias modeled by a torque. Breaking the mirror symmetry of the channel with respect to its axis suffices to generate a directed particle flow with orientation and magnitude which depend on the channel geometry and the particle swimming properties. This means that chiral microswimmers drift autonomously along a narrow channel under more general asymmetry conditions than previously reported, a property of potential impact on their fabrication and technological applications.