Ising-like Critical Behavior of Vortex Lattices in an Active Fluid.

  title={Ising-like Critical Behavior of Vortex Lattices in an Active Fluid.},
  author={Henning Reinken and Sebastian Heidenreich and Markus B{\"a}r and Sabine H. L. Klapp},
  journal={Physical review letters},
  volume={128 4},
Turbulent vortex structures emerging in bacterial active fluids can be organized into regular vortex lattices by weak geometrical constraints such as obstacles. Here we show, using a continuum-theoretical approach, that the formation and destruction of these patterns exhibit features of a continuous second-order equilibrium phase transition, including long-range correlations, divergent susceptibility, and critical slowing down. The emerging vorticity field can be mapped onto a two-dimensional… 

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