Directed collective motion of bacteria under channel confinement

  title={Directed collective motion of bacteria under channel confinement},
  author={Hugo Wioland and Enkeleida Lushi and Raymond E. Goldstein},
  journal={New Journal of Physics},
Dense suspensions of swimming bacteria are known to exhibit collective behaviour arising from the interplay of steric and hydrodynamic interactions. Unconfined suspensions exhibit transient, recurring vortices and jets, whereas those confined in circular domains may exhibit order in the form of a spiral vortex. Here we show that confinement into a long and narrow macroscopic ‘racetrack’ geometry stabilises bacterial motion to form a steady unidirectional circulation. This motion is reproduced… 

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