Accelerating cryogenic testing and characterization of new materials, designs, and fabrication methods for superconducting quantum devices with a fast and easy-to-use ADR-based cryostat.

The performance of superconducting qubits and their associated devices must be improved to minimize error rates and improve coherence times. This requires comprehensive testing and characterization of new materials, innovative designs, and novel fabrication methods. The systematic evaluation of these factors is cumbersome due to classic cryogenic solutions having long cooldown times, requiring trained engineers to operate, and relying on helium-3, an increasingly expensive resource.

We present novel cryostats¹ developed for the characterization and operation of quantum devices at sub-Kelvin temperatures, based on adiabatic demagnetization refrigeration. We describe how continuous sub-Kelvin cooling and wide-range temperature control can be achieved by combining multiple ADR units and mechanical thermal switches. We also present a novel sample loader mechanism² that allows cooling samples from room temperature to below 100 mK in less than 3 hours, in a fully automated way. Finally, we show how it can be used to study low-temperature characteristics of superconducting films and resonators, with less than 4 hours between successive measurements.

[1] Regnat et al. (2018) Cryogen-free cooling apparatus (EP 3163222). European Patent Office.

[2] Spallek et al. (2022) System and method for inserting a sample into a chamber (EP 3632560). European Patent Office.