Proximity-induced superconductivity in a narrow metallic wire

We present a study of the superconducting proximity effect on electron transport in hybrid metallic nanostructures. The effects of barrier transparency and geometrical confinement in lateral structures are compared. In a long narrow metallic (N) wire in contact with small superconducting (S) islands through mesoscopic normal-superconductor (N-S) junctions, a zero-resistance state is obtained. Experimental behavior diverge to a large extent from the classical models. Critical-current measurements are reported that show an anomalous amplitude and a nonconventional temperature dependence behavior.