Diffusion-facilitated transport of self-driven particles in polycrystalline structures

Abstract

We study particle transport in a polycrystalline system with mesoscale regular structures, which was inspired by ionic transport in solids. We found a novel type of congestion dynamics in which the density of particles spontaneously became strongly inhomogeneous with increasing driving force field and inverse temperature, leaving strongly localized pathways that allowed for substantial particle current. Consequently, particle current was maximized at a certain driving force strength and inverse temperature, which effectively avoided overcrowding of particles via a moderate level of diffusion. Our findings not only extend the theory of collective transport of self-propelled particles but also provide a baseline for understanding the transport properties of real polycrystalline systems, including superionic materials. Published by the American Physical Society 2024