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Development and characterization of a flux-pumped lumped element Josephson parametric amplifier

Martina Esposito, Joseph Rahamim, Andrew Patterson, Matthias Mergenthaler, James Wills, Giulio Campanaro, Takahiro Tsunoda, Peter Spring, Sophia Sosnina, Salha Jebari, Kitty Ratter, Giovanna Tancredi, Brian Vlastakis, Peter Leek

Published Jan 1, 2019• 4 citations

Abstract

Josephson parametric amplification is a tool of paramount importance in circuit-QED especially for the quantum-noise-limited single-shot read-out of superconducting qubits. We developed a Josephson parametric amplifier (JPA) based on a lumped-element LC resonator, in which the inductance L is composed by a geometric inductance and an array of 4 superconducting quantum interference devices (SQUIDs). We characterized the main figures of merit of the device, obtaining a −3 dB bandwidth BW = 15 MHz for a gain G = 21 dB and a 1 dB compression point P1dB = −115 dBm. The obtained results are promising for the future use of such JPA as the first stage of amplification for single-shot readout of superconducting qubits.

DOI: 10.1051/epjconf/201919800008

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