Flux-Driven Josephson Traveling-Wave Parametric Amplifier
A.B. Zorin · Physical Review Applied · 2019
With potentially quantum limited performance and wide frequency bandwidth, traveling-wave Josephson parametric amplifiers (TWJPAs) based on superconducting circuits are in urgent demand for quantum information processing. This study designs a TWJPA in which the interacting pump and signal/idler microwaves propagate with similar phase velocities through two different transmission lines, thereby enabling parametric gain. Such operation is possible due to a chain of SQUIDs that form the signal transmission line, which is magnetically coupled to a separate pump $L\phantom{\rule{0}{0ex}}C$ line. The proposed circuit may greatly simplify the measurement setup and solve the problem of pump depletion.