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arXiv · 1507.04480

Synchronization of particle motion in compressed two-dimensional plasma crystals

I. Laut·C. Räth·S. Zhdanov·V. Nosenko·L. Couëdel·H. M. Thomas
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Abstract

The collective motion of dust particles during the mode-coupling induced melting of a two-dimensional plasma crystal is explored in molecular dynamics simulations. The crystal is compressed horizontally by an anisotropic confinement. This compression leads to an asymmetric triggering of the mode-coupling instability which is accompanied by alternating chains of in-phase and anti-phase oscillating particles. A new order parameter is proposed to quantify the synchronization with respect to different directions of the crystal. Depending on the orientation of the confinement anisotropy, mode-coupling instability and synchronized motion are observed in one or two directions. Notably, the synchronization is found to be direction-dependent. The good agreement with experiments suggests that the confinement anisotropy can be used to explain the observed synchronization process.

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I. Laut, C. Räth, S. Zhdanov, V. Nosenko, L. Couëdel, H. M. Thomas. 2015-07-16. Synchronization of particle motion in compressed two-dimensional plasma crystals. https://doi.org/10.1209/0295-5075/110/65001

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