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arXiv · 2501.09453

Non-reciprocal scattering in a microwave frequency comb

Christoph L. Bock·J. C. Rivera Hernández·Fabio Lingua·David B. Haviland
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Abstract

We investigate nonreciprocal scattering within the modes of a microwave frequency comb. Adjusting the pump frequencies, amplitudes, and phases of a Josephson parametric oscillator, we control constructive interference for the $m \longrightarrow \ell$ scattering processes, while concurrently achieving destructive interference for the inverse process $\ell \longrightarrow m$. We outline the methodology for realizing nonreciprocity in the context of two-mode isolation and a three-mode circulation, which we extend to multiple modes. We find good agreement between the experiments and a linearized theoretical model. Nonreciprocal scattering expands the toolset for parametric control, with the potential to engineer alternative quantum correlations.

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Christoph L. Bock, J. C. Rivera Hernández, Fabio Lingua, David B. Haviland. 2025-01-16. Non-reciprocal scattering in a microwave frequency comb. https://doi.org/10.1103/kz53-dryz

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