Resonantly phase-matched Josephson junction traveling wave parametric amplifier

TL;DR

This paper introduces a resonant phase matching technique for Josephson-junction traveling wave parametric amplifiers, enabling high gain and broad bandwidth for cryogenic microwave measurements in quantum and astronomical applications.

Contribution

It presents a novel resonant phase matching method and a compact superconducting device design that significantly improves gain bandwidth product in Josephson parametric amplifiers.

Findings

Achieved 20 dB gain with 3 GHz bandwidth

Demonstrated saturation power of -98 dBm

Enabled broadband cryogenic microwave measurements

Abstract

We develop a technique to overcome phase-mismatch in Josephson-junction traveling wave parametric amplifiers in order to achieve high gain over a broad bandwidth. Using "resonant phase matching," we design a compact superconducting device consisting of a transmission line with subwavelength resonant inclusions that simultaneously achieves a gain of 20 dB, an instantaneous bandwidth of 3 GHz, and a saturation power of -98 dBm. Such an amplifier is well-suited to cryogenic broadband microwave measurements such as the multiplexed readout of quantum coherent circuits based on superconducting, semiconducting, or nano-mechanical elements as well as traditional astronomical detectors.