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Superconducting Fluctuation Corrections to the Thermal Current in Granular Metals

C. Biagini·R. Ferone·Rosario Fazio·F. W. J. Hekking·V. Tognetti
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Abstract

The first-order superconducting fluctuation corrections to the thermal conductivity of a granular metal are calculated. A suppression of thermal conductivity proportional to $T_c/(T-T_c)$ is observed in a region not too close to the critical temperature $T_c$. As $T\simeq T_c$, a saturation of the correction is found, and its sign depends on the ratio between the barrier transparency and the critical temperature. In both regimes, the Wiedemann-Franz law is violated.

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C. Biagini, R. Ferone, Rosario Fazio, F. W. J. Hekking, V. Tognetti. 2006-04-25. Superconducting Fluctuation Corrections to the Thermal Current in Granular Metals. https://doi.org/10.1103/physrevb.72.134510

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