Print Email Facebook Twitter Current-Phase Relation of Ballistic Graphene Josephson Junctions Title Current-Phase Relation of Ballistic Graphene Josephson Junctions Author Nanda, G. (TU Delft QN/Kavli Nanolab Delft; Kavli institute of nanoscience Delft) Aguilera Servin, J.L. (TU Delft QCD/Vandersypen Lab; Institute of Science and Technology Austria; Kavli institute of nanoscience Delft) Rakyta, P. (Eötvös University) Kormányos, A. (Universität Konstanz) Kleiner, Reinhold (Eberhard Karls Universität Tübingen) Koelle, Dieter (Eberhard Karls Universität Tübingen) Watanabe, K. (National Institute for Materials Science) Taniguchi, T. (National Institute for Materials Science) Vandersypen, L.M.K. (TU Delft QCD/Vandersypen Lab; TU Delft QN/Vandersypen Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft) Goswami, S. (TU Delft QN/Quantum Transport; TU Delft QRD/Kouwenhoven Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft) Date 2017 Abstract The current-phase relation (CPR) of a Josephson junction (JJ) determines how the supercurrent evolves with the superconducting phase difference across the junction. Knowledge of the CPR is essential in order to understand the response of a JJ to various external parameters. Despite the rising interest in ultraclean encapsulated graphene JJs, the CPR of such junctions remains unknown. Here, we use a fully gate-tunable graphene superconducting quantum intereference device (SQUID) to determine the CPR of ballistic graphene JJs. Each of the two JJs in the SQUID is made with graphene encapsulated in hexagonal boron nitride. By independently controlling the critical current of the JJs, we can operate the SQUID either in a symmetric or asymmetric configuration. The highly asymmetric SQUID allows us to phase-bias one of the JJs and thereby directly obtain its CPR. The CPR is found to be skewed, deviating significantly from a sinusoidal form. The skewness can be tuned with the gate voltage and oscillates in antiphase with Fabry-Pérot resistance oscillations of the ballistic graphene cavity. We compare our experiments with tight-binding calculations that include realistic graphene-superconductor interfaces and find a good qualitative agreement. Subject current-phase relationGrapheneJosephson junctionsSQUID To reference this document use: http://resolver.tudelft.nl/uuid:c12b41b6-f3a7-46a5-ba40-5409fcbf9b48 DOI https://doi.org/10.1021/acs.nanolett.7b00097 ISSN 1530-6984 Source Nano Letters: a journal dedicated to nanoscience and nanotechnology, 17 (6), 3396-3401 Part of collection Institutional Repository Document type journal article Rights © 2017 G. Nanda, J.L. Aguilera Servin, P. Rakyta, A. Kormányos, Reinhold Kleiner, Dieter Koelle, K. Watanabe, T. Taniguchi, L.M.K. Vandersypen, S. Goswami Files PDF acs.nanolett.7b00097.pdf 2.44 MB Close viewer /islandora/object/uuid:c12b41b6-f3a7-46a5-ba40-5409fcbf9b48/datastream/OBJ/view