MULTIGIGAHERTZ OPERATION OF 3-JUNCTION-INTERFEROMETER-BASED JOSEPHSONLATCHING LOGIC-CIRCUITS

Josephson latching logic gates require am sc power supply for correct operation. Owing to difficulty in fabricating Josephson regulators for targe power currents, multi-phase sinusoidal power supply is the pref erred method for multi-gigahertz operation. However, the inherently va riable sc power reduces device margin far covering process variations. As a result, there exists a strong relationship between circuit size, maximum operating frequency and circuit throughput for a given availa ble margin. The trade-offs between these performance criteria are anal yzed for 3-junction-interferometer-based logic gates. Experimental eva luation of the multigigahertz operation of smalt circuits showed that careful design of power supply networks that reduce power supply fluct uations will be needed to maximize performance. Simulation and experim ental results will be discussed.