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Transition from insulating to a non-insulating temperature dependence of the conductivity in granular metals

K. B. Efetov·A. Tschersich
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Abstract

We consider interaction effects in a granular normal metal at not very low temperatures. Assuming that all weak localization effects are suppressed by the temperature we replace the initial Hamiltonian by a proper functional of phases and study the possibility for a phase transition depending on the tunneling conductance $g$. It is demonstrated for any dimension that, while at small $g$ the conductivity decays with temperature exponentially, its temperature dependence is logarithmic at large $g.$ The formulae obtained are compared with an existing experiment and a good agreement is found.

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K. B. Efetov, A. Tschersich. 2002-04-12. Transition from insulating to a non-insulating temperature dependence of the conductivity in granular metals. https://doi.org/10.1209/epl%2Fi2002-00166-9

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