Integration of InAs-Al Heterostructures into Microwave Circuit*

Semiconductor-based Josephson junctions provide a platform to study the proximity effect and for the realization of topological superconductivity. Recently our group has demonstrated the possibility of having highly transparent contact between a superconductor and a semiconductor by combining high mobility Indium Arsenide (InAs) surface two dimensional electron gases (2DEGs) with epitaxially grown aluminum (Al) [1]. This allows for gate-tunable superconducting Josephson Junctions and consequently gate-tunable Transmons [2]. Here we present the integration of these InAs-Al heterostructures into microwave circuits such as Gatemon Qubits. The steps needed to fabricate on III-V material platform while mitigating microwave losses and microwave response will be discussed.

[1] W. Mayer, Appl. Phys. Lett. 114, 103104 (2019)
[2] L. Casparis, Nature Nanotechnology, volume 13, pages 915–919 (2018)