Cavity-Induced Strong Magnon-Magnon Coupling in Altermagnets

• DOI: 10.48550/arxiv.2307.00909
• Publication Date: 2023-01-01
• Authors: Zhejunyu Jin; Huanhuan Yang; Zhaozhuo Zeng; Yunshan Cao; Peng Yan
• Keywords: Magnon; Magnonics

Long-distance strong coupling between short-wavelength magnons remains an outstanding challenge in quantum magnonics, emerging interdiscipline magnonics and information science. Recently, altermagnets are identified as the third elementary class of magnets that break time-reversal symmetry without magnetization thus combine characteristics conventional collinear ferromagnets antiferromagnets. In this work, we show cavity photons can mediate long-distance exchange with opposite chiralities altermagnets, manifesting anticrossing magnon-polariton spectrum extremely dispersive regime. The predicted effective magnon-magnon strongly depends on magnon propagation direction, is highly anisotropic. Our findings intimately connected to intrinsic nature altermagnetic magnons, i.e., chirality-splitting-induced crossing which has no counterpart or antiferromagnets, may open a new path way for magnon-based processing altermagnets.