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arXiv · 1511.03790

Velocity condensation for magnetotactic bacteria

Jean-Francois Rupprecht·Nicolas Waisbord·Christophe Ybert·Cécile Cottin-Bizonne·Lydéric Bocquet
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Abstract

Magnetotactic swimmers tend to align along magnetic field lines against stochastic reorientations. We show that the swimming strategy, e.g. active Brownian motion versus run-and-tumble dynamics, strongly affects the orientation statistics. The latter can exhibit a velocity condensation whereby the alignment probability density diverges. As a consequence, we find that the swimming strategy affects the nature of the phase transition to collective motion, indicating that Lévy run-and-tumble walks can outperform active Brownian processes as strategies to trigger collective behavior.

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Jean-Francois Rupprecht, Nicolas Waisbord, Christophe Ybert, Cécile Cottin-Bizonne, Lydéric Bocquet. 2016-07-13. Velocity condensation for magnetotactic bacteria. https://doi.org/10.1103/physrevlett.116.168101

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