Resonant and off-resonant microwave signal manipulation in coupled superconducting resonators

TL;DR

This paper demonstrates and models a superconducting circuit capable of manipulating microwave signals at the single-photon level, including swapping fields between coupled resonators via tunable coupling.

Contribution

It introduces a novel integrated superconducting circuit with tunable coupling for microwave field manipulation, supported by both experimental results and theoretical modeling.

Findings

Successful microwave field swapping between resonators

Good agreement between experiments and simulations

Analysis of system behavior based on damping ratio

Abstract

We present an experimental demonstration as well as a theoretical model of an integrated circuit designed for the manipulation of a microwave field down to the single-photon level. The device is made of a superconducting resonator coupled to a transmission line via a second frequency-tunable resonator. The tunable resonator can be used as a tunable coupler between the fixed resonator and the transmission line. Moreover, the manipulation of the microwave field between the two resonators is possible. In particular, we demonstrate the swapping of the field from one resonator to the other by pulsing the frequency detuning between the two resonators. The behavior of the system, which determines how the device can be operated, is analyzed as a function of one key parameter of the system, the damping ratio of the coupled resonators. We show a good agreement between experiments and simulations, realized by solving a set of coupled differential equations.