CfAS scientist Martina Esposito, working in the Leek group, developed a Josephson parametric amplifier (JPA) based on a lumped-element LC resonator which includes an array of superconducting quantum interference devices (SQUIDs). The main figures of merit of the device are a bandwidth BW = 15 MHz, a maximum gain G = 21 dB and a 1-dB compression point of -115 dBm. The characterization of the gain of the amplifier is shown in the figure. The performance of the device is promising for the future use of the JPA as the first stage of amplification for single-shot readout of superconducting qubits. This work has been published as a conference paper in the proceedings of the QTech-2018 conference held in Paris in September 2018.
A new PhD student, Giulio Campanaro, recently joined the CfAS team working on the development of a new superconducting parametric amplifier based on travelling-wave Josephson amplification which has the advantage to provide a larger bandwidth, of the order of few GHz, and can be used for multiplexing qubit readout.