Investigation of signal isolation and transient characteristics in quantum-flux-parametron (QFP) circuits

Quantum-Flux-Parametron (QFP) gates whose input and output are inductively coupled with the next gate are proposed. According to the numerical simulation, the degree of signal isolation is improved and the output signal deformation is suppressed compared to the directly connected QFP gates. Majority gates that are capable of handling input signals much greater than three are improved in their functionality. Characteristics of the QFP gates upon application of an activation current are also investigated by the numerical simulation. The minimum time of the signal propagation between adjacent QFP gates is calculated to be 5 ps.