“…Here, superconducting circuits with Josephson junctions exhibit a solid and scalable technology platform stemming from their mature lithographic fabrication processes [2]. During the recent decades, fascinating superconducting rf components for the toolbox have been demonstrated, such as Josephson parametric amplifiers [3,4], kinetic inductance travelling-wave amplifiers [5,6], switches [7,8], circulators [9,10], isolators [11], beam splitters [12,13], phase shifters [14,15], and photon detectors [16][17][18]. In the future, these may be integrated into monolithic circuits for sophisticated quantum signal processing.…”