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arXiv · 1104.3779

Identifying anomalous diffusion and melting in dusty plasmas

Yan Feng·J. Goree·Bin Liu
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Abstract

Anomalous diffusion in liquids and the solid-liquid phase transition (melting) are studied in two-dimensional Yukawa systems. The self-intermediate scattering function (self-ISF), calculated from simulation data, exhibits a temporal decay, or relaxation, with a characteristic relaxation time. This decay is found to be useful for distinguishing normal and anomalous diffusion in a liquid, and for identifying the solid-liquid phase transition. For liquids, a scaling of the relaxation time with length scale is found. For the solid-liquid phase transition, the shape of the self-ISF curve is found to be a sensitive indicator of phase. Friction has a significant effect on the timing of relaxation, but not the melting point.

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Yan Feng, J. Goree, Bin Liu. 2011-04-19. Identifying anomalous diffusion and melting in dusty plasmas. https://doi.org/10.1103/physreve.82.036403

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