Josephson Gated Transistors and Electronics

Improving the energy efficiency of densely-integrated electronic is an important goal towards the sustainability of modern digitally connected society, in particular for what concerns high-performance computing datacenters. An important piece of the solution is found in the contacts between metallic leads and the semiconducting channels that constitute the core of transistors, the key active component in integrated circuits. A significant part of increasing the energy efficiency is tied to managing the resistance that appears between metals and semiconductors: the contact resistance. In JOGATE we utilise the unique superconducting properties in hybrid superconductorsemiconductor components to uncover the mechanisms contributing to the contact resistance and thereby improve it. In doing so, not only we contribute to solving a major obstacle for the energy efficiency of established digital electronics, but we obtain the superconducting analogues to the conventional transistors and diodes. These superconducting components are unique in that they enable new avenues for superconducting circuit design, resulting in opportunities in miniaturisation, performance and cost of devices that find application in communication, sensing and detection, signal amplification and routing. In JOGATE we wish to study superconducting transistors and diodes and to upgrade their fabrication processes to be compatible with the methods of large-scale integration, making it possible for Europe to lead their industrial production. In parallel, we contribute to finding ways of improving their performance, to ease practical adoption and impact in areas ranging from cryogenic electronics to demanding environments such as space applications. Finally, to demonstrate the value of the technology and to deliver important outcomes in the short-term, we develop two prototype devices for cryogenic microwave signal management: a radiofrequency switch and an integrated superconducting qubit control chip.