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arXiv · 2506.23497

Photonic Altermagnets: Magnetic Symmetries in Photonic Structures

Andrew Sungwook Kim·Youqiang Huang·Zhipei Sun·Q-Han Park·Hyunyong Choi
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Abstract

The unique physical properties of altermagnets, when transplanted to photonic systems, are anticipated to offer a new degree of freedom for engineering electromagnetic waves. Here, we show that a photonic analogue of altermagnetism can be mimicked in photonic crystals, where engineered photonic crystals can host spin space group symmetries. Our approach allows for the creation of spin-split bands and the corresponding transport properties provide an effective platform for circularly polarized light isolation without the need of geometrodynamic spin-orbit interaction. Beyond the concurrent solid-state materials, we anticipate our work to offer photonic crystals as a versatile platform to test the spin-split band properties and inspire optical designs for photospintronic applications.

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Andrew Sungwook Kim, Youqiang Huang, Zhipei Sun, Q-Han Park, Hyunyong Choi. 2025-06-30. Photonic Altermagnets: Magnetic Symmetries in Photonic Structures. https://arxiv.org/abs/2506.23497

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