High magnetic field stability in a planar graphene-NbSe SQUID
arXiv:2211.01020 · doi:10.1021/acs.nanolett.3c01552
Abstract
Thin NbSe retains superconductivity at high in-plane magnetic field up to 30 T. In this work we construct an atomically thin, all van der Waals SQUID, in which current flows between NbSe contacts through two parallel graphene weak links. This fully planar device remains uniquely stable at high in-plane field. This enables tracing the evolution of the critical current interference patterns as a function of the field up to 4.5 T, allowing nm-scale sensitivity to deviations from a perfect atomic plane. We present numerical methods to retrieve asymmetric current distributions J from measured interference maps, and suggest a new application of the dual junction geometry to probe the current density in the absence of phase information. The interference maps exhibit a striking field-driven transition, indicating a redistribution of supercurrents to narrow channels. Our results suggest the existence of a preferred conductance channel with an exceptional stability to in-plane magnetic field.
References in corpus (8)
- Fast pick up technique for high quality heterostructures of bilayer graphene and hexagonal boron nitride
- Spin-orbit driven band inversion in bilayer graphene by van der Waals proximity effect
- Edge currents shunt the insulating bulk in gapped graphene
- Highly Tunable Junctions and Nonlocal Josephson Effect in Magic Angle Graphene Tunneling Devices
- Anomalous Fraunhofer Interference in Epitaxial Superconductor-Semiconductor Josephson Junctions
- Planar graphene-NbSe Josephson junctions in a parallel magnetic field
- Proximity-induced superconductivity and Josephson critical current in quantum spin Hall systems
- Superconductivity in twisted Graphene heterostructures