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arXiv · 2006.14500

Active Janus particles in a complex plasma

V. Nosenko·F. Luoni·A. Kaouk·M. Rubin-Zuzic·H. Thomas
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Abstract

Active Janus particles suspended in a plasma were studied experimentally. The Janus particles were micron-size plastic microspheres, one half of which was coated with a thin layer of platinum. They were suspended in the plasma sheath of a radio-frequency discharge in argon at low pressure. The Janus particles moved in characteristic looped trajectories suggesting a combination of spinning and circling motion; their interactions led to the emergence of rich dynamics characterized by non-Maxwellian velocity distribution. The particle propulsion mechanism is discussed, the main force driving the particle motion is identified as photophoretic force.

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V. Nosenko, F. Luoni, A. Kaouk, M. Rubin-Zuzic, H. Thomas. 2020-06-25. Active Janus particles in a complex plasma. https://doi.org/10.1103/physrevresearch.2.033226

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