title: Superconducting junction of a single-crystalline au nanowire for an ideal Josephson device.
abstract: We report on the fabrication and measurements of a superconducting junction of a single-crystalline Au nanowire, connected to Al electrodes. The current-voltage characteristic curve shows a clear supercurrent branch below the superconducting transition temperature of Al and quantized voltage plateaus on application of microwave radiation, as expected from Josephson relations. Highly transparent (0.95) contacts very close to an ideal limit of 1 are formed at the interface between the normal metal (Au) and the superconductor (Al). The very high transparency is ascribed to the single crystallinity of a Au nanowire and the formation of an oxide-free contact between Au and Al. The subgap structures of the differential conductance are well explained by coherent multiple Andreev reflections (MAR), the hallmark of mesoscopic Josephson junctions. These observations demonstrate that single crystalline Au nanowires can be employed to develop novel quantum devices utilizing coherent electrical transport.
authors.affiliation: Korea Research Institute of Standards and Science, Daejeon 305-600, Korea.
authors.forename: Minkyung
authors.initials: M
authors.lastname: Jung
authors.forename: Hyunho
authors.initials: H
authors.lastname: Noh
authors.forename: Yong-Joo
authors.initials: YJ
authors.lastname: Doh
authors.forename: Woon
authors.initials: W
authors.lastname: Song
authors.forename: Yonuk
authors.initials: Y
authors.lastname: Chong
authors.forename: Mahn-Soo
authors.initials: MS
authors.lastname: Choi
authors.forename: Youngdong
authors.initials: Y
authors.lastname: Yoo
authors.forename: Kwanyong
authors.initials: K
authors.lastname: Seo
authors.forename: Nam
authors.initials: N
authors.lastname: Kim
authors.forename: Byung-Chill
authors.initials: BC
authors.lastname: Woo
authors.forename: Bongsoo
authors.initials: B
authors.lastname: Kim
authors.forename: Jinhee
authors.initials: J
authors.lastname: Kim
mesh_terms: D004553:Electric Conductivity; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008422:Materials Testing; D008670:Metals / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D012666:Semiconductors
chemical_list: D008670:Metals