Supercurrent in Multi-Terminal Ballistic Graphene Josephson Junctions*

We investigated electronic properties of encapsulated graphene samples with multiple superconducting terminals. Clean ballistic devices were fabricated from graphene sandwiched by boron nitride flakes and contacted with superconducting molybdenum-rhenium. These multi-terminal devices were studied at zero magnetic field to first investigate the supercurrent among adjacent and non-adjacent Josephson junctions. We then also measured the samples in the quantum Hall (QH) regime and studied the interplay between edge states and the superconducting contacts. We discuss our results in light of various mechanisms of chiral state propagation along the QH and superconducting interfaces.