Josephson Junction Field-Effect Transistors for Boolean Logic Cryogenic Applications

Josephson junction FETs (JJ-FETs) share design similarities with MOSFETs, except for the source/drain contacts being replaced by superconductors. Similarly, the super current due to proximity effect is tunable by the gate voltage. In light of recent advances in novel materials and fabrication techniques, we examine here the feasibility of JJ-FET-based Boolean logic and memory elements for cryogenic computing. Using a 2-D ballistic transport JJ-FET model, we implement circuit-level simulations for JJ-FET logic gates and discuss criteria for realizing signal restoration, as well as fan-out. We show that the JJ-FET is a promising candidate for very low-power, clocked voltage-level dynamic logic at cryogenic temperatures.