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arXiv · 2201.02671

Tuning of Strong Nonlinearity in rf SQUID Meta-Atoms

Ethan Zack·Daimeng Zhang·Melissa Trepanier·Jingnan Cai·Tamin Tai·Nikos Lazarides·Johanne Hizanidis·Steven M. Anlage
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Abstract

Strong nonlinearity of a self-resonant radio frequency superconducting quantum interference device (rf-SQUID) meta-atom is explored via intermodulation (IM) measurements. Previous work in zero dc magnetic flux showed a sharp onset of IM response as the frequency sweeps through the resonance. A second onset at higher frequency was also observed, creating a prominent gap in the IM response. By extending those measurements to nonzero dc flux, new dynamics are revealed, including: dc flux tunabililty of the aforementioned gaps, and enhanced IM response near geometric resonance of the rf-SQUID. These features observed experimentally are understood and analyzed theoretically through a combination of a steady state analytical modeling, and a full numerical treatment of the rf SQUID dynamics. The latter, in addition, predicts the presence of chaos in narrow parameter regimes. The understanding of intermodulation in rf-SQUID metamaterials is important for producing low-noise amplification of microwave signals and tunable filters.

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Ethan Zack, Daimeng Zhang, Melissa Trepanier, Jingnan Cai, Tamin Tai, Nikos Lazarides, Johanne Hizanidis, Steven M. Anlage. 2022-01-07. Tuning of Strong Nonlinearity in rf SQUID Meta-Atoms. https://doi.org/10.1103/physreve.105.044202

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