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arXiv · 1411.0964

Motion of two micro-wedges in a turbulent bacterial bath

Andreas Kaiser·Andrey Sokolov·Igor S. Aranson·Hartmut Löwen
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Abstract

The motion of a pair of micro-wedges ("carriers") in a turbulent bacterial bath is explored using computer simulations with explicit modeling of the bacteria and experiments. The orientation of the two micro-wedges is parallel and fixed by an applied magnetic field but the translational coordinates can move freely as induced by the bacterial bath. As a result, two carriers of same orientation move such that their mutual distance decreases. Eventually the two carriers stack on each other with no intervening bacteria exhibiting a stable dynamical mode where the two micro-wedges follow each other with the same velocity. These findings are in qualitative agreement with experiments on two micro-wedges in a bacterial bath. Our results provide insight into understanding the self-assembly of many micro-wedges in an active bath.

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Andreas Kaiser, Andrey Sokolov, Igor S. Aranson, Hartmut Löwen. 2015-03-12. Motion of two micro-wedges in a turbulent bacterial bath. https://doi.org/10.1140/epjst%2Fe2015-02459-x

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