Superconductivity in Disordered Thin Films: Giant Mesoscopic Fluctuations

Abstract

We discuss the intrinsic inhomogeneities of superconductive properties of uniformly disordered thin films with a large dimensionless conductance $g$. It is shown that mesoscopic fluctuations, which usually contain a small factor $1/g$, are crucially enhanced near the critical conductance $g_{cF}\gg 1$ where superconductivity is destroyed at $T=0$ due to Coulomb suppression of the Cooper attraction. This leads to strong spatial fluctuations of the local transition temperature and thus to the percolative nature of the thermal superconductive transition.