Photofocusing: Light and flow of phototactic microswimmer suspension

Abstract

We explore in this paper the phenomenon of photofocusing: a coupling between flow vorticity and biased swimming of microalgae toward a light source that produces a focusing of the microswimmer suspension. We combine experiments that investigate the stationary state of this phenomenon as well as the transition regime with analytical and numerical modeling. We show that the experimentally observed scalings on the width of the focalized region and the establishment length as a function of the flow velocity are well described by a simple theoretical model.

References in corpus (6)

• The hydrodynamics of swimming microorganisms
• Effective viscosity of microswimmer suspensions
• Nonlinear dynamics of a microswimmer in Poiseuille flow
• Light control of the flow of phototactic microswimmer suspensions
• Turbulent fluid acceleration generates clusters of gyrotactic microorganisms
• Gyrotactic trapping in laminar and turbulent Kolmogorov flow

Cited by in corpus (11)

• Photo-bioconvection: towards light-control of flows in active suspensions
• Gyrotactic phytoplankton in laminar and turbulent flows: a dynamical systems approach
• Lack of an equation of state for the nonequilibrium chemical potential of gases of active particles in contact
• Deflection of phototactic microswimmers through obstacle arrays
• Asymmetric pattern formation in microswimmer suspensions induced by orienting fields
• Controlling stability and transport of magnetic microswimmers by an external field
• Hydro-chemical interactions in dilute phoretic suspensions: from individual particle properties to collective organization
• Emergent pattern formation of active magnetic suspensions in an external field
• Collective dynamics and rheology of confined phoretic suspensions
• Active dipolar spheroids in shear flow and transverse field: Population splitting, cross-stream migration and orientational pinning
• Kinetic theory of decentralized learning for smart active matter