Integration of van der Waals superconductors into 2D-3D Hybrid Superconducting Circuits

van der Waals materials as a field have boomed in the last decade for multiple reasons. Not only are air stable vdW materials comparatively inexpensive and easy to work with, but they can be used to create structures that would have previously been impossible or extremely expensive to fabricate. The vdW superconductors are just as fascinating for their own properties, such as Ising superconductivity and 2D superconductivity, as they are fascinating for their ability to interface seamlessly with other van der Waals materials. Atomically-thin two-dimensional (2D) transitionmetal

dichalcogenide superconductors enable uniform, flat and clean van der Waals tunneling interfaces, motivating their integration into conventional superconducting circuits. We cover the properties and characteristics of the TMD superconductors before turning to focus more on how their properties and characteristics can best be used to build new things. The largest part of this body of work is integrating

2D and 3D superconductors. However, fully superconducting contact must be made between the 2D material and three-dimensional (3D) superconductors to employ standard

microwave drive and readout of qubits in such circuits. We present a method for creating zero-resistance contacts between 2D NbSe2 and 3D aluminum that behave

as Josephson junctions (JJs) with large effective areas compared to 3D-3D JJs. The devices formed from 2D TMD superconductors are strongly influenced by the geometry of the flakes themselves as well as the placement of the contacts to bulk 3D superconducting leads. We present a model for the supercurrent flow in a 2D-3D superconducting

structure by numerical solution of the Ginzburg-Landau equations and find good agreement with experiment. These results demonstrate a crucial step towards a new generation of hybrid superconducting quantum circuits. Lastly, we take

a step into that new generation of hybrid superconducting circuits by integrating 2D superconductors into RF resonant circuits in addition the the prior DC circuits.