title: Giant magnetoconductance oscillations in hybrid superconductor-semiconductor core/shell nanowire devices.
abstract: The magnetotransport of GaAs/InAs core/shell nanowires contacted by two superconducting Nb electrodes is investigated, where the InAs shell forms a tube-like conductive channel around the highly resistive GaAs core. By applying a magnetic field along the nanowire axis, regular magnetoconductance oscillations with an amplitude in the order of e(2)/h are observed. The oscillation amplitude is found to be larger by 2 orders of magnitude compared to the measurements of a reference sample with normal metal contacts. For the Nb-contacted core/shell nanowire the oscillation period corresponds to half a flux quantum Φ0/2 = h/2e in contrast to the period of Φ0 of the reference sample. The strongly enhanced magnetoconductance oscillations are explained by phase-coherent resonant Andreev reflections at the Nb-core/shell nanowire interface.
authors.affiliation: Peter Grünberg Institute (PGI-9) and JARA-Fundamentals of Future Information Technology, Forschungszentrum Jülich GmbH , 52425 Jülich, Germany.
authors.forename: Ö
authors.initials: Ö
authors.lastname: Gül
authors.forename: H Y
authors.initials: HY
authors.lastname: Günel
authors.forename: H
authors.initials: H
authors.lastname: Lüth
authors.forename: T
authors.initials: T
authors.lastname: Rieger
authors.forename: T
authors.initials: T
authors.lastname: Wenz
authors.forename: F
authors.initials: F
authors.lastname: Haas
authors.forename: M
authors.initials: M
authors.lastname: Lepsa
authors.forename: G
authors.initials: G
authors.lastname: Panaitov
authors.forename: D
authors.initials: D
authors.lastname: Grützmacher
authors.forename: Th
authors.initials: T
authors.lastname: Schäpers
keywords: Andreev reflection; GaAs/InAs core/shell nanowires; Josephson effect; magnetoconductance oscillations; reflectionless tunneling; superconducting electrodes