Hysteretic Critical State in Coplanar Josephson Junction with Monolayer Graphene Barrier

作者：Massarotti D; Jouault B; Rouco V; Campagnano G; Giuliano D; Lucignano P; Stornaiuolo D; Pepe G P; Lombardi F; Tafuri F; Tagliacozzo A

来源：Journal of Superconductivity and Novel Magnetism, 2017, 30(1): 5-14.

DOI：10.1007/s10948-016-3871-x

• Graphene
• Josephson effect
• Silicon carbide

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 I (c) when turning the field on, and a revival of I (c) 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.

• 出版日期2017-1