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arXiv · 2402.19394

Tunable compact on-chip superconducting switch

Julia Zotova·Alexander Semenov·Rui Wang·Yu Zhou·Oleg Astafiev·Jaw-Shen Tsai
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Abstract

We develop a compact four-port superconducting switch with a tunable operating frequency in the range of 4.8 GHz -- 7.3 GHz. Isolation between channel exceeds 20~dB over a bandwidth of several hundred megahertz, exceeding 40 dB at some frequencies. The footprint of the device is $80\times420~\mu$m. The tunability requires only a global flux bias without either permanent magnets or micro-electromechanical structures. As the switch is superconducting, the heat dissipation during operation is negligible. The device can operate at up to -80~dBm, which is equal to $2.5\times 10^6$ photons at 6 GHz per microsecond. The device show a possibility to be operated as a beamsplitter with tunable splitting ratio.

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Julia Zotova, Alexander Semenov, Rui Wang, Yu Zhou, Oleg Astafiev, Jaw-Shen Tsai. 2024-02-29. Tunable compact on-chip superconducting switch. https://doi.org/10.1103/physrevapplied.21.024059

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