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arXiv · 2305.17816

Josephson parametric amplifier with Chebyshev gain profile and high saturation

Ryan Kaufman·Theodore White·Mark I. Dykman·Andrea Iorio·George Stirling·Sabrina Hong·Alex Opremcak·Andreas Bengtsson·Lara Faoro·Joseph C. Bardin·Tim Burger·Robert Gasca·Ofer Naaman
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Abstract

We demonstrate a Josephson parametric amplifier design with a band-pass impedance matching network based on a third-order Chebyshev prototype. We measured eight amplifiers operating at 4.6 GHz that exhibit gains of 20 dB with less than 1 dB gain ripple and up to 500 MHz bandwidth. The amplifiers further achieve high output saturation powers around -73 dBm based on the use of rf-SQUID arrays as their nonlinear element. We characterize the system readout efficiency and its signal-to-noise ratio near saturation using a Sycamore processor, finding the data consistent with near quantum limited noise performance of the amplifiers. In addition, we measure the amplifiers' intermodulation distortion in two-tone experiments as a function of input power and inter-tone detuning, and observe excess distortion at small detuning with a pronounced dip as a function of signal power, which we interpret in terms of power-dependent dielectric losses.

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Ryan Kaufman, Theodore White, Mark I. Dykman, Andrea Iorio, George Stirling, Sabrina Hong, Alex Opremcak, Andreas Bengtsson, Lara Faoro, Joseph C. Bardin, Tim Burger, Robert Gasca, Ofer Naaman. 2023-05-28. Josephson parametric amplifier with Chebyshev gain profile and high saturation. https://arxiv.org/abs/2305.17816

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