Tracking current path in multi-terminal graphene Josephson junctions

Multiterminal Josephson junctions have been predicted to be platforms to observe various exotic phenomena such as new topological phases of matter [1], correlated states [2-5] or the so-called Andreev molecules [6,7]. In order to control the electronic properties of these complex devices, it is important to comprehend and track the supercurrent flow with respect to their geometries and superconducting lead peculiarities.
Here, we investigated the supercurrent in multi-terminal superconductor-graphene-superconductor (SGS) junctions. Together with magnetic interferometry experiments in these multiterminal graphene devices, we clearly observe that the contact transparencies can be very different from one lead to the other which mainly drives the entire transport properties in SGS. Our work provides insights of the supercurrent flow in multiterminal Josephson junctions and paves the way for further investigations in more complex multiterminal devices