Project duration: 06/2023 – 06/2026.
Numerous sensitive electronic and photonic devices require extremely low temperatures for their operation. Application fields benefiting from low-temperature-enabled devices and systems range from material analysis to space technology. Timely examples include different sensors such as X-ray and THz detectors, but also superconductive quantum processors, which all require refrigeration close to the absolute zero of thermodynamic temperature.
Nowadays, superconductive quantum computers and other cryogenic devices requiring sub-1 K operation are typically cooled by so-called dilution refrigerators, which are multi-stage coolers based on pumping of cryogenic liquids. Even though modern dry/cryogen-free dilution refrigerators are commercial technology they are still expensive and large scientific instruments with cryoliquids inside and complex gas handling system [Fig. a)]. The complexity of this refrigerator arises, especially, from the coldest stage, the operation of which is based on pumping of a 3He-4He mixture.
The core technological goal of the project is building a device where continuous refrigeration to pumped 3He temperature range can be achieved without 3He, by designing, fabricating and measuring cascaded SoCool coolers and individual stages for different temperature ranges [Fig. b)].