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arXiv · 2208.13339

Passive superconducting circulator on a chip

Rohit Navarathna·Dat Thanh Le·Andrés Rosario Hamann·Hien Duy Nguyen·Thomas M. Stace·Arkady Fedorov
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Abstract

An on-chip microwave circulator that is compatible with superconducting devices is a key element for scale-up of superconducting circuits. Previous approaches to integrating circulators on chip involve either external driving that requires extra microwave lines or a strong magnetic field that would compromise superconductivity. Here we report the first proof-of-principle realisation of a passive on-chip circulator which is made from a superconducting loop interrupted by three notionally-identical Josephson junctions and is tuned with only DC control fields. Our experimental results shows evidence for nonreciprocal scattering, and excellent agreement with theoretical simulations. We also present a detailed analysis of quasiparticle tunneling in our device using a hidden Markov model. By reducing the junction asymmetry and utilising the known methods of protection from quasiparticles, we anticipate that Josephson-loop circulator will become ubiquitous in superconducting circuits.

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Rohit Navarathna, Dat Thanh Le, Andrés Rosario Hamann, Hien Duy Nguyen, Thomas M. Stace, Arkady Fedorov. 2022-09-05. Passive superconducting circulator on a chip. https://doi.org/10.1103/physrevlett.130.037001

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