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arXiv · 2310.16814

Motility-induced clustering of active particles under soft confinement

Timo Knippenberg·Ashreya Jayaram·Thomas Speck·Clemens Bechinger
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Abstract

We investigate the structural and dynamic properties of active Brownian particles (APs) confined within a soft annulus-shaped channel. Depending on the strength of the confinement and the P\'eclet number, we observe a novel re-entrant behavior that is not present in unconfined systems. Our findings are substantiated by numerical simulations and analytical considerations, revealing that this behavior arises from the strong coupling between the P\'eclet number and the effective confining dimensionality of the APs. Beyond highlighting the important influence of soft boundaries on APs, our research holds significance for future applications of micro-robotic systems.

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Timo Knippenberg, Ashreya Jayaram, Thomas Speck, Clemens Bechinger. 2023-10-25. Motility-induced clustering of active particles under soft confinement. https://doi.org/10.1103/physrevlett.133.048301

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