Spin-Glass State of a Randomly Diluted Granular Superconductor

Abstract
A randomly diluted lattice of Josephson tunnel junctions is used as a model to generate a replicated Landau-Ginzburg field theory describing the properties of diluted superconductors near the percolation threshold. The model predicts Meissner and Abrikosov phases and a spin-glass phase with frozen currents, a nonvanishing Edwards-Anderson order parameter, and power-law decay of correlations of the magnetic field.