Escape Kinetics of Self-Propelled Janus Particles from a Cavity: Numerical Simulations

We numerically investigate the escape kinetics of elliptic Janus particles from narrow two-dimensional cavities with reflecting walls. The self-propulsion velocity of the Janus particle is directed along either their major (prolate) or minor axis (oblate). We show that the mean exit time is very sensitive to the cavity geometry, particle shape and self-propulsion strength. The mean exit time is found to be a minimum when the self-propulsion length is equal to the cavity size. We also find the optimum mean escape time as a function of the self-propulsion velocity, translational diffusion, and particle shape. Thus, effective transport control mechanisms for Janus particles in a channel can be implemented.