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arXiv · 1812.08825

Multi-stable free states of an active particle from a coherent memory dynamics

Vincent Bacot·Stéphane Perrard·Matthieu Labousse·Yves Couder·Emmanuel Fort
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Abstract

We investigate the dynamics of a deterministic self-propelled particle endowed with coherent memory. We evidence experimentally and numerically that it exhibits several stable free states. The system is composed of a self-propelled drop bouncing on a vibrated liquid driven by the waves it emits at each bounce. This object possesses a propulsion memory resulting from the coherent interference of the waves accumulated along its path. We investigate here the transitory regime of the build-up of the dynamics which leads to velocity modulations. Experiments and numerical simulations enable us to explore unchartered areas of the phase space and reveal the existence of a self-sustained oscillatory regime. Finally, we show the co-existence of several free states. This feature emerges both from the spatio-temporal non-locality of this path memory dynamics as well as the wave nature of the driving mechanism.

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Vincent Bacot, Stéphane Perrard, Matthieu Labousse, Yves Couder, Emmanuel Fort. 2018-12-20. Multi-stable free states of an active particle from a coherent memory dynamics. https://doi.org/10.1103/physrevlett.122.104303

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