Josephson junction current-switched logic circuits

A review is given of recent Josephson circuits studies, Emphasis is placed on logic designs employing current-switched gates. These rely on a direct summing of the gate bias current with control current inputs to cause switching from the low-resistance state to the high-resistance state. Present designs are simple, compact and relatively tolerant of fabrication variations. At the same time they retain the advantages of high speed and low power inherent in Josephson devices. Use of these so-called Jaws gates in huffle flip-flops is discussed.