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arXiv · 2508.10483

Jamming of active particles in narrow pores: Implications for ratchet effect and diffusion coefficient

Šimon Pajger·František Slanina
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Abstract

We study the behavior of colloidal active particles interacting via steric repulsion in various quasi-1D geometries. We mainly focus on active particles with high P\'eclet number. We discuss 3 phenomena closely tied to those systems: motility-induced phase separation (or dynamical freezing), ratchet effect (which takes place if the geometry has broken spatial symmetry), and the enhanced diffusion coefficient. We study those particles using numerical simulations employing an ASEP-like model. Besides direct numerical simulations we study the model by mean-field approximation and by solving the coarse-grained hydrodynamic equations.

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Šimon Pajger, František Slanina. 2025-08-14. Jamming of active particles in narrow pores: Implications for ratchet effect and diffusion coefficient. https://doi.org/10.1088/1742-5468%2Fadefb0

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