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arXiv · 1109.6647

Space-time dependence of the anomalous exponent of electric transport in the disorder model

Takeshi Egami·Koshiro Suzuki·Katsuhiro Watanabe
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Abstract

Space-time dependence of the anomalous exponent of electric transport in the disorder model is presented. We show that the anomalous exponent depends on time, according to the time-evolution of the number of the effective neighbouring sites. Transition from subdiffusive to normal transport at long-enough time is recovered. The above result indicates that the spatial structure, specifically the network structure, of the hopping sites might be a novel element which determines the anomalous exponent. This leads to the feature that the scaling property of the electric transport to time is insensitive to other elements, such as the distance of the sites or the spatial dimension of the system. These findings are verified by means of Monte Carlo simulation. The relation of the result to the conventional knowledge of the Multiple Trapping Model is shown by deriving it as a special case of the disorder model.

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Takeshi Egami, Koshiro Suzuki, Katsuhiro Watanabe. 2012-09-28. Space-time dependence of the anomalous exponent of electric transport in the disorder model. https://doi.org/10.1088/1751-8113%2F45%2F46%2F465002

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