Effective diffusion constant in a two dimensional medium of charged point scatterers
arXiv:cond-mat/0311125 · doi:10.1088/0305-4470/37/6/005
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.
9 pages IOP LaTex, no figures