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arXiv · 2406.03063

In-operando microwave scattering-parameter calibrated measurement of a Josephson travelling wave parametric amplifier

S. H. Shin·M. Stanley·W. N. Wong·T. Sweetnam·A. Elarabi·T. Lindström·N. M. Ridler·S. E. de Graaf
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Abstract

Superconducting travelling wave parametric amplifiers (TWPAs) are broadband near-quantum limited microwave amplifiers commonly used for qubit readout and a wide range of other applications in quantum technologies. The performance of these amplifiers depends on achieving impedance matching to minimise reflected signals. Here we apply a microwave calibration technique to extract the S-parameters of a Josephson junction based TWPA in-operando. This enables reflections occurring at the TWPA and its extended network of components to be quantified, and we find that the in-operation performance can be well described by the off-state measured S-parameters.

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S. H. Shin, M. Stanley, W. N. Wong, T. Sweetnam, A. Elarabi, T. Lindström, N. M. Ridler, S. E. de Graaf. 2024-06-05. In-operando microwave scattering-parameter calibrated measurement of a Josephson travelling wave parametric amplifier. https://arxiv.org/abs/2406.03063

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