The tunability of magnons enables their interaction with various other quantum excitations, including photons, paving the route for novel hybrid quantum systems. Here, we study magnon-photon coupling using a high-quality factor split-ring resonator and single-crystal yttrium iron garnet (YIG) sphere at room temperature. We investigate the dependence of the coupling strength on the size of the sphere and find that the coupling is stronger for spheres with a larger diameter as predicted by theory. Furthermore, we demonstrate strong magnon-photon coupling by varying the position of the YIG sphere within the resonator. Our experimental results reveal the expected correlation between the coupling strength and the rf magnetic field. These findings demonstrate the control of coherent magnon-photon coupling through the theoretically predicted square-root dependence on the spin density in the ferromagnetic medium and the magnetic dipolar interaction in a planar resonator.

中文翻译：

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控制平面几何中的磁子-光子耦合

磁振子的可调谐性使其能够与包括光子在内的各种其他量子激发相互作用，为新型混合量子系统铺平了道路。在这里，我们在室温下使用高质量因数开口环谐振器和单晶钇铁石榴石 (YIG) 球体研究磁子-光子耦合。我们研究了耦合强度对球体尺寸的依赖性，发现正如理论预测的那样，直径较大的球体耦合更强。此外，我们通过改变谐振器内 YIG 球的位置来证明强磁子-光子耦合。我们的实验结果揭示了耦合强度和射频磁场之间的预期相关性。这些发现证明了通过理论上预测的平方根对铁磁介质中自旋密度和平面谐振器中磁偶极相互作用的依赖性来控制相干磁子-光子耦合。