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arXiv · 1412.1131

Self-Sustained Density Oscillations of Swimming Bacteria Confined in Microchambers

M. Paoluzzi·R. Di Leonardo·L. Angelani
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Abstract

We numerically study the dynamics of run-and-tumble particles confined in two chambers connected by thin channels. Two dominant dynamical behaviors emerge: (i) an oscillatory pumping state, in which particles periodically fill the two vessels and (ii) a circulating flow state, dynamically maintaining a near constant population level in the containers when connected by two channels. We demonstrate that the oscillatory behaviour arises from the combination of a narrow channel, preventing bacteria reorientation, and a density dependent motility inside the chambers.

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M. Paoluzzi, R. Di Leonardo, L. Angelani. 2014-12-02. Self-Sustained Density Oscillations of Swimming Bacteria Confined in Microchambers. https://doi.org/10.1103/physrevlett.115.188303

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