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Weak Localization in Metallic Granular Media

Ya. M. Blanter·V. M. Vinokur·L. I. Glazman
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Abstract

We investigate the interference correction to the conductivity of a medium consisting of metallic grains connected by tunnel junctions. Tunneling conductance between the grains, $e^2g_{\rm T}/π\hbar$, is assumed to be large, $g_{\rm T}\gg 1$. We demonstrate that the weak localization correction to conductivity exhibits a crossover at temperature $T\sim g^2_{\rm T}δ$, where $δ$ is the mean level spacing in a single grain. At the crossover, the phase relaxation time determined by the electron-electron interaction becomes of the order of the dwell time of an electron in a grain. Below the crossover temperature, the granular array behaves as a continuous medium, while above the crossover the weak localization effect is largely a single-junction phenomenon. We elucidate the signatures of the granular structure in the temperature and magnetic field dependence of the weak localization correction.

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Ya. M. Blanter, V. M. Vinokur, L. I. Glazman. 2006-01-30. Weak Localization in Metallic Granular Media. https://doi.org/10.1103/physrevb.73.165322

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