Localisation and superconducting fluctuations in Pb-Cu thin films

Abstract

Thin discontinuous films of lead, of thickness 10-100 AA, were evaporated onto 120 AA copper films in order to examine the superconductivity and localisation effects. The temperature and magnetic field dependences of the resistance were studied. It was found that the addition of lead on the copper film increased the spin-orbit interaction, and that the inelastic scattering time was shortened at 10K due to the additional contribution of phonons of from the lead. Superconducting fluctuations in some films were observed far above Tc (T>or approximately=3Tc). The results are described well by localisation theories and by Larkin's theory of superconducting fluctuations.