Patent ID: 10615783

Abstract:
A reciprocal quantum logic (RQL) phase-mode D flip-flop accepts a data input and a logical clock input. A D flip-flop with an enable input further accepts enable input and further requires that the enable be asserted high to allow the data input to change the output on the logical clock pulse. The flip-flop includes a storage loop and a comparator, each of which includes Josephson junctions (JJs). The storage loop stores the data input, provided as a positive or negative single flux quantum (SFQ) pulse, is stored in the storage loop as positive or negative state, respectively, effectively biasing a JJ shared between the storage loop and the comparator. The data input is captured to the output upon clocking (or enabled clocking), when a clock pulse causes the shared JJ to preferentially trigger over an escape JJ in the comparator, the shared JJ having been biased by storage loop current.