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arXiv · 2201.04091

Intermittent Attractive Interactions Lead to Microphase Separation in Non-motile Active Matter

Henry Alston·Andrew O. Parry·Raphaël Voituriez·Thibault Bertrand
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Abstract

Non-motile active matter exhibits a wide range of non-equilibrium collective phenomena yet examples are crucially lacking in the literature. We present a microscopic model inspired by the bacteria {\it Neisseria Meningitidis} in which diffusive agents feel intermittent attractive forces. Through a formal coarse-graining procedure, we show that this truly scalar model of active matter exhibits the time-reversal-symmetry breaking terms defining the {\it Active Model B+} class. In particular, we confirm the presence of microphase separation by solving the kinetic equations numerically. We show that the switching rate controlling the interactions provides a regulation mechanism tuning the typical cluster size, e.g. in populations of bacteria interacting via type IV pili.

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Henry Alston, Andrew O. Parry, Raphaël Voituriez, Thibault Bertrand. 2022-01-11. Intermittent Attractive Interactions Lead to Microphase Separation in Non-motile Active Matter. https://doi.org/10.1103/physreve.106.034603

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