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arXiv · 2402.00493

Large scale zigzag pattern emerging from circulating active shakers

Gaspard Junot·Marco De Corato·Pietro Tierno
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Abstract

We report the emergence of large zigzag bands in a population of reversibly actuated magnetic rotors that behave as active shakers, namely squirmers that shake the fluid around them without moving. The shakers collectively organize into dynamic structures displaying self-similar growth, and generate topological defects in form of cusps that connect vortices of rolling particles with alternating chirality. By combining experimental analysis with particle-based simulation, we show that the special flow field created by the shakers is the only ingredient needed to reproduce the observed spatiotemporal pattern. We unveil a self-organization scenario in a collection of driven particles in an viscoelastic medium emerging from the reduced particle degrees of freedom, as here the frozen orientational motion of the shakers.

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Gaspard Junot, Marco De Corato, Pietro Tierno. 2024-02-01. Large scale zigzag pattern emerging from circulating active shakers. https://doi.org/10.1103/physrevlett.131.068301

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