Dynamic clustering of passive colloids in dense suspensions of motile bacteria

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.

16 pages, 16 figures

References in corpus (7)

• Motility-Induced Phase Separation
• Spontaneous motion in hierarchically assembled active matter
• Meso-scale turbulence in living fluids
• Activity-induced phase separation and self-assembly in mixtures of active and passive particles
• Active phase separation by turning toward regions of higher density
• Motile dislocations knead odd crystals into whorls
• Interparticle torques suppress motility-induced phase separation for rodlike particles

Cited by in corpus (5)

• Phase Separation Driven by Active Flows
• Ostwald-like ripening in the two-dimensional clustering of passive particles induced by swimming bacteria
• Phase Ordering in Binary Mixtures of Active Nematic Fluids
• Transient Pattern Formation in an Active Matter Contact Poisoning Model
• Self-organised structures in mixed active-passive suspensions due to hydrodynamic interactions