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arXiv · 0707.4237

Fluctuation spectroscopy of granularity in superconducting structures

I. V. Lerner·A. A. Varlamov·V. M. Vinokur
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Abstract

We suggest to use `fluctuation spectroscopy' as a method to detect granularity in a disordered metal close to a superconducting transition. We show that with lowering temperature $T$ the resistance $R(T)$ of a system of relatively large grains initially grows due to the fluctuation suppression of the one-electron tunneling but decreases with further lowering $T$ due to the coherent charge transfer of the fluctuation Cooper pairs. Under certain conditions, such a maximum in $R(T)$ turns out to be sensitive to weak magnetic fields due to a novel Maki -- Thompson type mechanism.

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I. V. Lerner, A. A. Varlamov, V. M. Vinokur. 2008-03-23. Fluctuation spectroscopy of granularity in superconducting structures. https://doi.org/10.1103/physrevlett.100.117003

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