Multifrequency Floquet Engineering of Magnon Polaritons

TL;DR

This paper demonstrates Floquet engineering of cavity magnon-polaritons by modulating the microwave cavity frequency with two-frequency drives, revealing new spectral features and offering an alternative control method.

Contribution

It introduces a novel approach to Floquet engineering using cavity frequency modulation and two-frequency drives, expanding control over magnon-photon hybrid systems.

Findings

Spectrum depends on relative amplitude and phase of two drive tones.

New anticrossings appear between previously uncoupled sidebands.

Comparison shows qualitatively different features from single-frequency modulation.

Abstract

Floquet engineering of cavity magnon-polaritons by periodically modulating the magnon frequency has recently attracted much interest as a way to manipulate the energy spectrum of magnon-photon hybrid systems. However, modulating the frequency of magnons by a time-varying bias magnetic field can be challenging. We demonstrate cavity magnon-polariton Floquet engineering by modulating the microwave cavity frequency, allowing large modulation depth and bandwidth. We apply commensurate two-frequency Floquet modulations with the higher frequency at twice and three times the lower frequency, and demonstrate that the resulting spectrum depends on the relative amplitude and phase of the two drive tones. In comparison with single-frequency Floquet modulations, the spectrum has qualitatively different features; in particular, new anticrossings appear between previously uncoupled sidebands. Our platform offers an alternative way to manipulate Floquet quasi-energy levels in hybrid systems.