Gate-defined Quantum Wires with Superconducting Contacts in Epitaxial Al/InAs Heterostructures

Hybrid semiconductor-superconductor devices offer the exciting opportunity of gate-tunability for Josephson junctions and the search for toplogical superconductivity. We systematically study switching current and Fraunhofer oscillations in gate-tunable Josephson junctions on our epitaxially grown Al/InAs material heterostructure. We study in and out of the gap features of these junctions where we tune the density or area using gate bias. These studies are extended to the case of 1D transport using a gate-defined quantum point contact placed within the Josephson junction, and the nature of proximitized superconductivity in 1D is explored.