Spatial heterogeneity can facilitate the target search of self-propelled particles.

A numerical investigation of the target search dynamics of self-propelled particles (SPPs) in heterogeneous environments is presented in this work. We show that the spatial heterogeneity has a dramatic effect on the target search dynamics of SPPs. The relative magnitude of the self-propulsion length l and the radius of the circular domain R determines how the mean search time of SPPs τ depends on the area fraction of fixed obstacles ϕ. For l < R, the target search process is diffusion-dominated so that a monotonic increase in τ with increasing ϕ is observed. For l > R, τ is shown to be a non-monotonic convex function as a function of ϕ due to the interplay of the distribution-dominated and diffusion-dominated dynamic regimes. Furthermore, at fixed ϕ, τ shows a minimum upon increasing the self-propulsion velocity v of a SPP of a slow rotational diffusion when it searches for a target at low ϕ, while it decreases monotonically at high ϕ. The present work highlights that the introduction of spatial heterogeneity causes rich dynamic behaviors of a SPP searching for a target, and deepens our understanding of the transport of active matter in heterogeneous media.