We experimentally and theoretically study the coupling between magnons and microwave photons at zero static magnetic field in a system combined by a planar superconducting cavity and a van der Waals antiferromagnetic insulator CrCl₃ crystal. Using high-temperature superconductor DyBaCO, we fabricate a planar superconducting cavity with a high-quality factor. The antiferromagnetic resonance of CrCl₃ has a finite resonance frequency within a microwave electronics range at zero static magnetic field, and this frequency is sensitive to the temperature. Tuning the temperature to make the antiferromagnetic resonance mode of CrCl₃ approaching the cavity mode, we experimentally achieve the coupling between the magnon in CrCl₃ and the microwave photon in cavity. An anticrossing feature of the transmission spectra mapping indicates the coupling of magnons and photons at zero static magnetic field. The cooperativity of the hybrid system is 76, indicating a strong coherent information exchange between photons and magnons in CrCl₃.

中文翻译：

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反铁磁体 CrCl3 中的零场磁振子-光子耦合

我们从实验和理论上研究了在由平面超导腔和范德华反铁磁绝缘体 CrCl ₃晶体组合的系统中零静磁场下磁振子和微波光子之间的耦合。使用高温超导体 DyBaCO，我们制造了具有高质量因子的平面超导腔。CrCl ₃的反铁磁谐振在零静磁场的微波电子范围内具有有限的谐振频率，并且该频率对温度敏感。调节温度使CrCl ₃的反铁磁共振模式接近腔模，我们通过实验实现了CrCl _{3 中}磁振子之间的耦合和腔内的微波光子。透射光谱映射的反交叉特征表明在零静磁场下磁振子和光子的耦合。混合系统的协同性为 76，表明 CrCl _{3 中}光子和磁振子之间的强相干信息交换。