Invited Review Article: The Josephson bifurcation amplifier

R. Vijay, M. H. Devoret, I. Siddiqi
2009 Review of Scientific Instruments  
Josephson junction parametric amplifiers are playing a crucial role in the readout chain in superconducting quantum information experiments. However, their integration with current 3D cavity implementations poses the problem of transitioning between waveguide, coax cables, and planar circuits. Moreover, Josephson amplifiers require auxiliary microwave components, like directional couplers and/or hybrids, that are sources of spurious losses and impedance mismatches that limit measurement
more » ... cy and amplifier tunability. We have developed a wireless architecture for these parametric amplifiers that eliminates superfluous microwave components and interconnects. This greatly simplifies their assembly and integration into experiments. We present an experimental realization of such a device operating in the 9-11 GHz band with about 100 MHz of amplitude gain-bandwidth product, on par with devices mounted in conventional sample holders. The simpler impedance environment presented to the amplifier also results in increased amplifier tunability. V C 2014 AIP Publishing LLC. [http://dx.
doi:10.1063/1.3224703 pmid:19947710 fatcat:yoqbwzbeubhwxas2wkf4rke3fu