SELF-CONSISTENT TRANSPORT-PROPERTIES OF SUPERCONDUCTING NANOSTRUCTURES

By solving the Bogoliubov-de Gennes equation self-consistently, we com pute transport properties of various normal-superconducting mesoscopic structures. Three structures are considered; a single superconducting island, a superconducting island with a delta-function scatterer at o ne interface and a superconducting island with a delta-function scatte rer at tile centre of the island. Tile calculated self-consistent I-V characteristics show significant structure, arising from the competiti on between scattering processes at the boundaries of the island and mo dification of tile order parameter by quasi-particles and superflow. W hen the order parameter is significantly modified by the transport cur rent, it is noted that the magnitude of the differential conductance o f a single-channel conductor can exceed 2e(2)/h.