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arXiv · 1904.10855

Active particles powered by Quincke rotation in a bulk fluid

Debasish Das·Eric Lauga
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Abstract

Dielectric particles suspended in a weakly conducting fluid are known to spontaneously start rotating under the action of a sufficiently strong uniform DC electric field due to the Quincke rotation instability. This rotation can be converted into translation when the particles are placed near a surface providing useful model systems for active matter. Using a combination of numerical simulations and theoretical models, we demonstrate that it is possible to convert this spontaneous Quincke rotation into spontaneous translation in a plane perpendicular to the electric field in the absence of surfaces by relying on geometrical asymmetry instead.

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Debasish Das, Eric Lauga. 2019-04-24. Active particles powered by Quincke rotation in a bulk fluid. https://doi.org/10.1103/physrevlett.122.194503

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