Realization of planar Josephson junction devices on a Nb-InAs platform

Superconductor-semiconductor heterostructures are useful platforms for realizing gate-tunable quantum devices and studying topological superconductivity. Here, we report progress towards interfacing near-surface InAs quantum wells with Niobium. We fabricate planar Josephson junction-based devices and characterize their electronic properties. Compared to prototypical Al-based devices, Nb can induce a larger superconducting gap in the semiconductor. This allows for a wider range of operating temperatures and magnetic fields. We present avenues for realizing high temperature, flux-tunable superconducting qubits on this material platform. Lastly, we discuss how we can leverage our planar junction geometry to implement high operating frequency qubits and junction array devices with an enhanced Josephson plasma frequency.