FisMat2017 - Submission - View

Abstract's title: Incipient Berezinskii-Kosterlitz-Thouless transition in coplanar graphene Josephson junctions
Submitting author: Arturo Tagliacozzo
Affiliation: Dipartimento di Fisica, Universita' di Napoli Federico II
Affiliation Address: Complesso di Monte S.Angelo, Via Cintia, 80126 Napoli
Country: Italy
Oral presentation/Poster (Author's request): Oral presentation
Other authors and affiliations: B.Jouault 1, D.Massarotti 2,3, F.Tafuri 3,4 , and A. Tagliacozzo3,4 1 Laboratoire Charles Coulomb, UMR 5221 CNRS-UM2,Université Montpellier 2,place Eugéne Bataillon - CC074 F-34095 Montpellier, France 2 Dipartimento Ingegneria dell'Informazione, Seconda Università di Napoli, I-81031Aversa, Italy 3 CNR-SPIN, Monte S. Angelo-Via Cintia, I-80126, Napoli, Italy, 4 Dipartimento di Fisica, Università di Napoli Federico II, Via Cintia, I-80126 Napoli, Italy

 Graphene grown on SiC by Chemical Vapor Deposition (CVD) offer centimeter size monolayer areas on top of which contacts can be deposited  with the desired patterning. Various coplanar submicrometer Graphene/Aluminum Josephson Junctions have been tested on the same flake. Josephson coupling and moderate dissipation coexist with a remarkable hysteretic collapse and revival of the Josephson supercurrent when the magnetic field is cycled. Similar hystereses are found in granular systems and are usually justified within the Bean Critical State model (CSM). We provide evidence that the involved vortex dynamics originates from fluctuations due to an incipient Berezinskii -Kosterlitz-Thouless transition. 




       [1]     D. Massarotti, B. Jouault, V. Rouco, S. Charpentier, T. Bauch, A. Michon, A. De Candia, P. Lucignano, F. Lombardi,  F. Tafuri, and A. Tagliacozzo, Phys. Rev. B 94, 054525 (2016). 

[2]  B. Jouault, S. Charpentier, D. Massarotti, A. Michon, M. Paillet, J.-R. Huntzinger, A. Tiberj, A.-A. Zahab, T. Bauch, P. Lucignano, A. Tagliacozzo, F. Lombardi, F. Tafuri, "Josephson coupling in junctions made of monolayer graphene grown on SiC", Journal Superconductivity and Novel Magnetism 29,1145 ( 2016)

[3]  D. Massarotti, B. Jouault, V. Rouco, G. Campagnano, D. Giuliano, P.Lucignano, D. Stornaiuolo, G. P. Pepe, F. Lombardi, F. Tafuri, A. Tagliacozzo,”Hysteretic Critical State in Coplanar Josephson Junction with Monolayer Graphene Barrier”, J Supercond Nov Magn 30: 5 (2017).