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arXiv · 2303.10925

Meter-scale strong coupling between magnons and photons

Jinwei Rao·C. Y. Wang·Bimu Yao·Z. J. Chen·K. X. Zhao·Wei Lu
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Abstract

We experimentally realize a meter-scale strong coupling effect between magnons and photons at room temperature, with a coherent coupling of 20 m and a dissipative coupling of 7.6 m. To this end, we integrate a saturable gain into a microwave cavity and then couple this active cavity to a magnon mode via a long coaxial cable. The gain compensates for the cavity dissipation, but preserves the cavity radiation that mediates the indirect photon-magnon coupling. It thus enables the long-range strong photon-magnon coupling. With full access to traveling waves, we demonstrate a remote control of photon-magnon coupling by modulating the phase and amplitude of traveling waves, rather than reconfiguring subsystems themselves. Our method for realizing long-range strong coupling in cavity magnonics provides a general idea for other physical systems. Our experimental achievements may promote the construction of information networks based on cavity magnonics.

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Jinwei Rao, C. Y. Wang, Bimu Yao, Z. J. Chen, K. X. Zhao, Wei Lu. 2023-03-20. Meter-scale strong coupling between magnons and photons. https://arxiv.org/abs/2303.10925

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