Curvature-driven wall accumulation in chiral active particles
Abstract
We study a dilute system of non-motile chiral active particles confined in geometries ranging from straight channels to circular enclosures. Activity is introduced through chiral particle-wall interactions, modeled as tangential wall forces that generate the edge currents characteristic of chiral active matter. Remarkably, although the particles lack self-propulsion, these boundary currents induce density inhomogeneities. We show that boundary curvature drives a wall accumulation phenomenon: particles remain uniformly distributed in straight channels but accumulate near the boundaries of circular confinements. Numerical simulations and a hydrodynamic theory for the density and momentum fields consistently capture this curvature-induced wall-accumulation. These results identify boundary curvature as a fundamental control parameter for chiral edge transport and confinement-induced organization, with potential experimental relevance to spinning colloids and granular spinners.
Cite
@article{arxiv.2607.01948,
title = {Curvature-driven wall accumulation in chiral active particles},
author = {Alessandro Petrini and Raphaël Maire and Umberto Marini Bettolo Marconi and Lorenzo Caprini},
journal= {arXiv preprint arXiv:2607.01948},
year = {2026}
}