A simple high‐performance current‐switched Josephson gate

A versatile current‐switched gate is described which consists of two Josephson tunnel junctions and a small resistor in a loop. The directly combined bias and control currents flow through one junction in the zero‐voltage state, causing the switching. The second junction and the resistor provide isolation between input and output after switching. The switching speed of a few tens of picoseconds and the microwatt power dissipation are comparable to those of other present designs. The design is particularly simple, compact, and easy to fabricate.