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Universal temperature dependence of the conductivity of a strongly disordered granular metal

A. R. Akhmerov·A. S. Ioselevich
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Abstract

A disordered array of metal grains with large and random intergrain conductances is studied within the one-loop accuracy renormalization group approach. While at low level of disorder the dependence of conductivity on log T is nonuniversal (it depends on details of the array's geometry), for strong disorder this dependence is described by a universal nonlinear function, which depends only on the array's dimensionality. In two dimensions this function is found numerically. The dimensional crossover in granular films is discussed.

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A. R. Akhmerov, A. S. Ioselevich. 2006-02-03. Universal temperature dependence of the conductivity of a strongly disordered granular metal. https://doi.org/10.1134/s0021364006050067

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