Proximity effects in quench-condensed granular superconductors and ferromagnets

We report on a study of proximity effects in quench-condensed superconducting (Pb) and ferromagnetic (Ni) granular films in which we are able to deposit sequential layers of material and measure transport and magnetoresistance properties in-situ for different degrees of material coverage. We find that adding a normal (non-superconducting or non-ferromagnetic) overlayer to isolated Pb or Ni grains enhances long-range order in the film. We interpret these results as being due to proximity effects where the grains are coupled via the weak order-parameter induced in the overlayer material. (orig.)