High Magnetic Field Stability in a Planar Graphene-NbSe SQUID.

Thin NbSe retains superconductivity at a high in-plane magnetic field up to 30 T. In this work we construct a novel atomically thin, all van der Waals SQUID, in which current flows between NbSe contacts through two parallel graphene weak links. The 2D planar SQUID remains uniquely stable at high in-plane field, which enables tracing critical current interference patterns as a function of the field up to 4.

Quantum-dot assisted spectroscopy of degeneracy-lifted Landau levels in graphene.

Energy spectroscopy of strongly interacting phases requires probes which minimize screening while retaining spectral resolution and local sensitivity. Here, we demonstrate that such probes can be realized using atomic sized quantum dots bound to defects in hexagonal Boron Nitride tunnel barriers, placed at nanometric distance from graphene. With dot energies capacitively tuned by a planar graphite electrode, dot-assisted tunneling becomes highly sensitive to the graphene excitation spectrum.