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arXiv · 2110.02294

Dynamic clustering of passive colloids in dense suspensions of motile bacteria

Shreyas Gokhale·Junang Li·Alexandre Solon·Jeff Gore·Nikta Fakhri
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Abstract

Mixtures of active and passive particles are predicted to exhibit a variety of nonequilibrium phases. Here we report a dynamic clustering phase in mixtures of colloids and motile bacteria. We show that colloidal clustering results from a balance between bond breaking due to persistent active motion and bond stabilization due to torques that align active particle velocity tangentially to the passive particle surface. Furthermore, dynamic clustering spans a broad regime between diffusivity-based and motility-induced phase separation that subsumes typical bacterial motility parameters.

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Shreyas Gokhale, Junang Li, Alexandre Solon, Jeff Gore, Nikta Fakhri. 2021-10-05. Dynamic clustering of passive colloids in dense suspensions of motile bacteria. https://doi.org/10.1103/physreve.105.054605

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