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arXiv · 2111.05851

Light propagation and magnon-photon coupling in optically dispersive magnetic media

V. A. S. V. Bittencourt·I. Liberal·S. Viola Kusminskiy
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Abstract

Achieving strong coupling between light and matter excitations in hybrid systems is a benchmark for the implementation of quantum technologies. We recently proposed [arXiv:2110.02984] that strong single-particle coupling between magnons and light can be realized in a magnetized epsilon-near-zero (ENZ) medium, in which magneto-optical effects are enhanced. Here we present a detailed derivation of the magnon-photon coupling Hamiltonian in dispersive media both for degenerate and non-degenerate optical modes, and show the enhancement of the coupling near the ENZ frequency. Moreover, we show that the coupling of magnons to plane-wave non-degenerate Voigt modes vanishes at specific frequencies due to polarization selection rules tuned by dispersion. Finally, we present specific results using a Lorentz dispersion model. Our results pave the way for the design of dispersive optomagnonic systems, providing a general theoretical framework for describing engineering ENZ-based optomagnonic systems.

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V. A. S. V. Bittencourt, I. Liberal, S. Viola Kusminskiy. 2021-11-10. Light propagation and magnon-photon coupling in optically dispersive magnetic media. https://doi.org/10.1103/physrevb.105.014409

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