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Josephson parametric amplification is a tool of paramount importance in circuit quantum electrodynamics (circuit-QED), especially for the quantum-noise-limited single-shot readout of superconducting qubits. I will first present the development and characterization of a flux-pumped 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 superconducting quantum interference devices (SQUIDs) [1]. In addition, I will present preliminary experiments where the JPA is used as the first stage of amplification for the readout of a superconducting qubit based on a coaxial architecture recently developed in our lab in Oxford [2]. Finally, I will introduce my future scientific direction based on using JPAs for generation and control of non-classical states in microwave photons. [1] M. Esposito et al. EPJ Web of Conferences 198, 00008 (2019) [2] J. Rahamim et al. Applied Physics Letters 110, 222602 (2017)

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Martina Esposito, University of Oxford
Seminar Room of the Institute of Physics II
Contact: Yoichi Ando