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arXiv · 2304.04378

Josephson Parametric Amplifier in Axion Experiments

Jinmyeong Kim·Boris I. Ivanov·Çağlar Kutlu·Seongtae Park·Arjan F. Van Loo·Yasunobu Nakamura·Sergey V. Uchaikin·Seonjeong Oh·Violeta Gkika·Andrei Matlashov·Woohyun Chung·Yannis K. Semertzidis
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Abstract

The axion is a hypothetical particle, a promising candidate for dark matter, and a solution to the strong CP problem. Axion haloscope search experiments deal with a signal power comparable to noise uncertainty at millikelvin temperature. We use a flux-driven Josephson parametric amplifier (JPA) with the aim of approaching a noise level near the theoretically allowed limit of half quanta. In our measurements to characterize the JPA we have found the added noise to the system with a JPA as the first-stage amplifier to be lower than 110 mK at the frequencies from 0.938 GHz to 0.963 GHz.

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Jinmyeong Kim, Boris I. Ivanov, Çağlar Kutlu, Seongtae Park, Arjan F. Van Loo, Yasunobu Nakamura, Sergey V. Uchaikin, Seonjeong Oh, Violeta Gkika, Andrei Matlashov, Woohyun Chung, Yannis K. Semertzidis. 2023-04-10. Josephson Parametric Amplifier in Axion Experiments. https://doi.org/10.7566/jpscp.38.011199

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