Print Email Facebook Twitter Two-dimensional Josephson vortex lattice and anomalously slow decay of the Fraunhofer oscillations in a ballistic SNS junction with a warped Fermi surface Title Two-dimensional Josephson vortex lattice and anomalously slow decay of the Fraunhofer oscillations in a ballistic SNS junction with a warped Fermi surface Author Ostroukh, V. P. (Universiteit Leiden) Baxevanis, B. (Universiteit Leiden) Akhmerov, A.R. (TU Delft QN/Akhmerov Group) Beenakker, C.I.M. (Universiteit Leiden) Date 2016-09-16 Abstract The critical current of a Josephson junction is an oscillatory function of the enclosed magnetic flux Φ, because of quantum interference modulated with periodicity h/2e. We calculate these Fraunhofer oscillations in a two-dimensional (2D) ballistic superconductor-normal-metal-superconductor (SNS) junction. For a Fermi circle the amplitude of the oscillations decays as 1/Φ or faster. If the Fermi circle is strongly warped, as it is on a square lattice near the band center, we find that the amplitude decays slower, 1/Φ, when the magnetic length lm=/eB drops below the separation L of the NS interfaces. The crossover to the slow decay of the critical current is accompanied by the appearance of a 2D array of current vortices and antivortices in the normal region, which form a bipartite rectangular lattice with lattice constant ≃lm2/L. The 2D lattice vanishes for a circular Fermi surface, when only the usual single row of Josephson vortices remains. To reference this document use: http://resolver.tudelft.nl/uuid:5bf7bad8-d648-45a9-9ba5-49f595f0c966 DOI https://doi.org/10.1103/PhysRevB.94.094514 ISSN 1098-0121 Source Physical Review B (Condensed Matter and Materials Physics), 94 (9), 1-11 Part of collection Institutional Repository Document type journal article Rights © 2016 V. P. Ostroukh, B. Baxevanis, A.R. Akhmerov, C.I.M. Beenakker Files PDF PhysRevB.94.094514.pdf 3.25 MB Close viewer /islandora/object/uuid:5bf7bad8-d648-45a9-9ba5-49f595f0c966/datastream/OBJ/view