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Effective diffusion constant in a two dimensional medium of charged point scatterers

D. S. Dean·I. T. Drummond·R. R. Horgan
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Abstract

We obtain exact results for the effective diffusion constant of a two dimensional Langevin tracer particle in the force field generated by charged point scatterers with quenched positions. We show that if the point scatterers have a screened Coulomb (Yukawa) potential and are uniformly and independently distributed then the effective diffusion constant obeys the Volgel-Fulcher-Tammann law where it vanishes. Exact results are also obtained for pure Coulomb scatterers frozen in an equilibrium configuration of the same temperature as that of the tracer.

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D. S. Dean, I. T. Drummond, R. R. Horgan. 2003-11-06. Effective diffusion constant in a two dimensional medium of charged point scatterers. https://doi.org/10.1088/0305-4470%2F37%2F6%2F005

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