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arXiv · 0801.0531

Ac hopping conduction at extreme disorder takes place on the percolating cluster

Thomas B. Schrøder·Jeppe C. Dyre
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Abstract

Simulations of the random barrier model show that ac currents at extreme disorder are carried almost entirely by the percolating cluster slightly above threshold; thus contradicting traditional theories contributions from isolated low-activation-energy clusters are negligible. The effective medium approximation in conjunction with the Alexander-Orbach conjecture leads to an excellent analytical fit to the universal ac conductivity with no nontrivial fitting parameters.

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Thomas B. Schrøder, Jeppe C. Dyre. 2008-06-06. Ac hopping conduction at extreme disorder takes place on the percolating cluster. https://doi.org/10.1103/physrevlett.101.025901

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