Measurement of current transfer time in a tunneling cryotron flip-flop

This letter reports the operation of a tunneling cryotron flip-flop in which a current transfer rate of 10⁷A/s is achieved. The measured time of 2 ns required to transfer 20 mA is in excellent agreement with predicted values. These measurements imply a junction transition time appreciably smaller than 800 ps, the previously measured upper bound.