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arXiv · 2106.02928

Magnetic-free traveling-wave nonreciprocal superconducting microwave components

Dengke Zhang·Jaw-Shen Tsai
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Abstract

We propose a design to realize integrated broadband nonreciprocal microwave isolators and circulators using superconducting circuit elements without any magnetic materials. To obtain a broadband response, we develop a waveguide-based design by temporal modulations. The corresponding compact traveling-wave structure is implemented with integrated superconducting composite right-/left-handed transmission lines. The calculations show that the bandwidth of 580 MHz can be realized over a nonreciprocal isolation of 20 dB in reflections. Such on-chip isolators and circulators are useful for cryogenic integrated microwave connections and measurements, such as protecting qubits from the amplified reflected signal in multiplexed readout.

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Dengke Zhang, Jaw-Shen Tsai. 2021-06-05. Magnetic-free traveling-wave nonreciprocal superconducting microwave components. https://doi.org/10.1103/physrevapplied.15.064013

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