Dynamics of a Brownian circle swimmer

TL;DR

This paper investigates the motion of a Brownian circle swimmer in a confining channel, revealing a sliding mode near walls that significantly accelerates the particle, with potential enhancement through optimal torque-to-force ratios.

Contribution

It introduces a combined theoretical and simulation study of Brownian circle swimmers, highlighting the sliding mode and acceleration effects near walls.

Findings

Sliding mode causes significant acceleration near walls

Optimal torque-to-force ratio enhances motion

Wall proximity dramatically affects swimmer dynamics

Abstract

Self-propelled particles move along circles rather than along a straight line when their driving force does not coincide with their propagation direction. Examples include confined bacteria and spermatozoa, catalytically driven nanorods, active, anisotropic colloidal particles and vibrated granulates. Using a non-Hamiltonian rate theory and computer simulations, we study the motion of a Brownian "circle swimmer" in a confining channel. A sliding mode close to the wall leads to a huge acceleration as compared to the bulk motion, which can further be enhanced by an optimal effective torque-to-force ratio.