2012/01/17 by F. Chiodi, M. Ferrier, S. Guéron +7 · 46 citations
Mathematics · Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Computational physics #Computer science #Condensed matter physics #Flux (metallurgy) #Gaussian #Geometry #Integer (computer science) #Magnetic field #Magnetic flux #Materials science #Mathematical analysis #Mathematics #Monotonic function #Physics #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Quantum mechanics #Semiclassical physics #Square (algebra) #cond-mat.mes-hall #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.86.064510
published in Physical Review B 86(6) (American Physical Society) · 5 pages, 4 figures
arxiv created 2012/01/17 · openalex publication_date 2012/08/09 · arxiv updated 2013/05/29 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We have measured the critical current dependence on the magnetic flux of two long SNS junctions differing by the normal wire geometry. The samples are made by a Au wire connected to W contacts, via focused ion beam assisted deposition. We could tune the magnetic pattern from the monotonic Gaussian-like decay of a quasi-one-dimensional (1D) normal wire to the Fraunhofer-like pattern of a square normal wire. We explain the monotonic limit with a semiclassical 1D model, and we fit both field dependencies with numerical simulations of the two-dimensional Usadel equations. Furthermore, we observe both integer and fractional Shapiro steps. The magnetic flux dependence of the integer steps reproduces as expected that of the critical current Ic, while fractional steps decay slower with the flux than Ic.