title: Anomalous behavior of superconducting-normal mesoscopic structures near T(c)
abstract: We observe a maximum in the conductance of Al/n-GaAs junctions at temperatures 20 mK lower than the superconducting transition temperature (T(c)). This is the first observation of a peak in the conductance near the superconducting transition in superconducting-normal (S/N) junctions. To accommodate this effect we calculate the full temperature dependence of the conductance of these structures, invoking quasiclassical Green's functions in the diffusive limit. In addition to the well-known low-temperature peak at temperatures on the order of the Thouless energy, we find a maximum near T(c). This peak has the same origin as the subgap conductance observed in S/N junctions at low temperatures.
authors.affiliation: Cavendish Laboratory, University of Cambridge, Madingley Road CB3 0HE, United Kingdom.
authors.initials: S
authors.lastname: Shapira
authors.initials: EH
authors.lastname: Linfield
authors.initials: CJ
authors.lastname: Lambert
authors.initials: R
authors.lastname: Seviour
authors.initials: AF
authors.lastname: Volkov
authors.initials: AV
authors.lastname: Zaitsev