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arXiv · 1201.1711

Ion-Streaming Induced Order Transition in 3D Dust Clusters

Patrick Ludwig·Hanno Kählert·Michael Bonitz
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Abstract

Dust Dynamics Simulations utilizing a dynamical screening approach are performed to study the effect of ion-streaming on the self-organized structures in a three-dimensional spherically confined complex (dusty) plasma. Varying the Mach number M - the ratio of ion drift velocity to the sound velocity, the simulations reproduce the experimentally observed cluster configurations in the two limiting cases: at M=0 strongly correlated crystalline structures consisting of nested spherical shells (Yukawa balls) and, for M\geq1, flow-aligned dust chains, respectively. In addition, our simulations reveal a discontinuous transition between these two limits. It is found that already a moderate ion drift velocity (M\approx0.1) destabilizes the highly ordered Yukawa balls and initiates an abrupt melting transition. The critical value of M is found to be independent of the cluster size.

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Patrick Ludwig, Hanno Kählert, Michael Bonitz. 2012-01-09. Ion-Streaming Induced Order Transition in 3D Dust Clusters. https://doi.org/10.1088/0741-3335%2F54%2F4%2F045011

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