Hysteretic Critical State in Coplanar Josephson Junction with Monolayer Graphene Barrier

  • D. Massarotti
  • B. Jouault
  • V. Rouco
  • G. Campagnano
  • D. Giuliano
  • P. Lucignano
  • D. Stornaiuolo
  • G. P. Pepe
  • F. Lombardi
  • F. Tafuri
  • A. Tagliacozzo
Letter

Abstract

Coplanar Al/graphene/Al junctions fabricated on the same graphene sheet deposited on silicon carbide (SiC), show robust Josephson coupling at subKelvin temperature, when the separations between the electrodes is below 400 nm. Remarkably, a hysteretic Critical State sets in when ramping an orthogonal magnetic field, with a sudden collapse of the Josephson critical current Ic when turning the field on, and a revival of Ic when inverting the sweep. Similar hysteresis can be found in granular superconducting films which may undergo the Berezinskii-Kosterlitz-Thouless transition. Here, we give quantitative arguments to prove that this odd behavior of the magnetoconductance gives evidence for an incipient Berezinskii-Kosterlitz-Thouless transition with drift and pinning of fluctuating free vortices induced by the current bias.

Keywords

Graphene Josephson effect Silicon carbide 

Notes

Acknowledgments

The authors thank the Swedish Foundation for Strategic Research (SSF) under the project “Graphene based high frequency electronics” at Chalmers, where the samples were patterned and the collaboration of S. Charpentier and T. Bauch. Discussions with L. Benfatto, V.Bouchiat, P. Brouwer and Ya.V. Kopelevich are gratefully acknowledged. Work supported by PICS CNRS-CNR 2014-2016 “Transport phenomena and Proximity-induced Superconductivity in Graphene junctions,” FIRB “HybridNanoDev” RBFR1236VV (Italy) and by EU FP7, under grant agreement no 604391 Graphene Flagship.

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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • D. Massarotti
    • 1
    • 2
  • B. Jouault
    • 3
  • V. Rouco
    • 4
  • G. Campagnano
    • 2
    • 4
  • D. Giuliano
    • 5
    • 6
  • P. Lucignano
    • 2
    • 4
  • D. Stornaiuolo
    • 2
    • 4
  • G. P. Pepe
    • 2
    • 4
  • F. Lombardi
    • 7
  • F. Tafuri
    • 1
    • 2
  • A. Tagliacozzo
    • 2
    • 4
    • 6
  1. 1.Dipartimento di Ingegneria Industriale e dell’InformazioneSeconda Universitá di NapoliAversaItaly
  2. 2.CNR-SPINNapoliItaly
  3. 3.Laboratoire Charles Coulomb UMR 5221Université Montpellier-CNRSMontpellierFrance
  4. 4.Dipartimento di Fisica “E. Pancini”Università di Napoli “Federico II”NapoliItaly
  5. 5.Dipartimento di FisicaUniversità della Calabria Arcavacata di RendeCosenzaItaly
  6. 6.I.N.F.N., Gruppo collegato di CosenzaCosenzaItaly
  7. 7.Department of Microtechnology and NanoscienceChalmers University of TechnologyGöteborgSweden

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