NAND Gate for SFQ Logic Circuits

摘要

We propose a universal NAND logic gate based on single flux quantum (SFQ) logic. The NAND gate enables the con- struction of any logic circuits. In the proposed gate, three su- perconducting loops share two Josephson junctions (JJs). The critical currents of the JJs were desiglled to allow each of any two loops to trap an SFQ at the same time. We simulated dy- namic operation of this NAND gate. The results show that the NAND gate can operate with a delay time of 45 ps, and the power consumption of this circuit is close to 0.06 μW/gate.