Superconducting Fluctuation Corrections to the Thermal Current in   Granular Metals
  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. 
C. Biagini, R. Ferone, Rosario Fazio, F.W.J. Hekking, V. Tognetti