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Universality of ac-conduction in anisotropic disordered systems: An effective medium approximation study

Sebastian Bustingorry
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Abstract

Anisotropic disordered system are studied in this work within the random barrier model. In such systems the transition probabilities in different directions have different probability density functions. The frequency-dependent conductivity at low temperatures is obtained using an effective medium approximation. It is shown that the isotropic universal ac-conduction law, $σ\ln σ=u$, is recovered if properly scaled conductivity ($σ$) and frequency ($u$) variables are used.

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BibTeXRIS

Sebastian Bustingorry. 2005-04-12. Universality of ac-conduction in anisotropic disordered systems: An effective medium approximation study. https://doi.org/10.1103/physrevb.71.132201

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