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arXiv · 1701.03270

Wake-mediated propulsion of an upstream particle in two-dimensional plasma crystals

Ingo Laut·Christoph Räth·Sergey K. Zhdanov·Vladimir Nosenko·Gregor E. Morfill·Hubertus M. Thomas
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Abstract

The wake-mediated propulsion of an "extra" particle in a channel of two neighboring rows of a two-dimensional plasma crystal, observed experimentally by Du et al. [Phys. Rev. E 89, 021101(R) (2014)], is explained in simulations and theory. We use the simple model of a pointlike ion wake charge to reproduce this intriguing effect in simulations, allowing for a detailed investigation and a deeper understanding of the underlying dynamics. We show that the nonreciprocity of the particle interaction, owing to the wake charges, is responsible for a broken symmetry of the channel that enables a persistent self-propelled motion of the extra particle. We find good agreement of the terminal extra-particle velocity with our theoretical considerations and with experiments.

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Ingo Laut, Christoph Räth, Sergey K. Zhdanov, Vladimir Nosenko, Gregor E. Morfill, Hubertus M. Thomas. 2017-01-12. Wake-mediated propulsion of an upstream particle in two-dimensional plasma crystals. https://doi.org/10.1103/physrevlett.118.075002

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