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arXiv · 2406.19046

Ultrastrongly-coupled and Directionally-nonreciprocal Magnon-polaritons in Magnetochiral Metamolecules

Kentaro Mita·Takahiro Chiba·Toshiyuki Kodama·Tetsuya Ueda·Toshihiro Nakanishi·Kei Sawada·Satoshi Tomita
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Abstract

We experimentally demonstrate magnon-polaritons with ultrastrong coupling and directional nonreciprocity in a metamolecule lacking time-reversal and space-inversion symmetries at room temperature. These experimental results are reproduced well via numerical simulations and theoretical consideration. Ultrastrong coupling is due to a direct interaction of magnons in the magnetic meta-atom with microwave photons confined in the chiral meta-atom as a resonator. Our results reveal a crucial step in identifying deepstrongly-coupled and optically-moving magnon-polaritons for hybrid quantum systems, synthetic gauge fields, and quasi-particle ``chemistry'' using metamaterials.

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Kentaro Mita, Takahiro Chiba, Toshiyuki Kodama, Tetsuya Ueda, Toshihiro Nakanishi, Kei Sawada, Satoshi Tomita. 2024-06-27. Ultrastrongly-coupled and Directionally-nonreciprocal Magnon-polaritons in Magnetochiral Metamolecules. https://doi.org/10.1103/physrevapplied.23.l011004

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