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arXiv · 2209.14643

Strong to ultra-strong coherent coupling measurements in a YIG/cavity system at room temperature

Guillaume Bourcin·Jeremy Bourhill·Vincent Vlaminck·Vincent Castel
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Abstract

We present an experimental study of the strong to ultra-strong coupling regimes at room temperature in frequency-reconfigurable 3D re-entrant cavities coupled with a YIG slab. The observed coupling rate, defined as the ratio of the coupling strength to the cavity frequency of interest, ranges from 12% to 59%. We show that certain considerations must be taken into account when analyzing the polaritonic branches of a cavity spintronic device where the RF field is highly focused in the magnetic material. Our observations are in excellent agreement with electromagnetic finite element simulations in the frequency domain.

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Guillaume Bourcin, Jeremy Bourhill, Vincent Vlaminck, Vincent Castel. 2022-09-29. Strong to ultra-strong coherent coupling measurements in a YIG/cavity system at room temperature. https://doi.org/10.1103/physrevb.107.214423

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