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Test of the Stokes-Einstein relation in a two-dimensional Yukawa liquid

Bin Liu·J. Goree
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Abstract

The Stokes-Einstein relation, relating the diffusion and viscosity coefficients D and eta, is tested in two dimensions. An equilibrium molecular-dynamics simulation was used with a Yukawa pair potential. Regimes are identified where motion is diffusive and D is meaningful. The Stokes-Einstein relation, D ~ kT, was found to be violated near the disordering transition; under these conditions collective particle motion exhibits dynamical heterogeneity. At slightly higher temperatures, however, the Stokes-Einstein relation is valid. These results may be testable in strongly-coupled dusty plasma experiments.

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Bin Liu, J. Goree. 2005-11-08. Test of the Stokes-Einstein relation in a two-dimensional Yukawa liquid. https://doi.org/10.1103/physrevlett.96.015005

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