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arXiv · 2301.01856

Wetting dynamics by mixtures of fast and slow self-propelled particles

Mauricio Rojas-Vega·Pablo de Castro·Rodrigo Soto
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Abstract

We study active surface wetting using a minimal model of bacteria that takes into account the intrinsic motility diversity of living matter. A mixture of "fast" and "slow" self-propelled Brownian particles is considered in the presence of a wall. The evolution of the wetting layer thickness shows an overshoot before stationarity and its composition evolves in two stages, equilibrating after a slow elimination of excess particles. Non-monotonic evolutions are shown to arise from delayed avalanches towards the dilute phase combined with the emergence of a transient particle front.

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Mauricio Rojas-Vega, Pablo de Castro, Rodrigo Soto. 2023-01-05. Wetting dynamics by mixtures of fast and slow self-propelled particles. https://doi.org/10.1103/physreve.107.014608

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