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arXiv · 2304.07289

Higher-order exceptional points in loss-free waveguide arrays with negative-index materials

Xin-Zhe Zhang·Li-Ting Wu·Ru-Zhi Luo·Jing Chen
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Abstract

Negative-index materials (NIMs) are shown to support optical anti-parity-time (anti-PT) symmetry even when they are lossless. Here we prove the feasibility in achieving higher-order exceptional points (EPs) in loss-free waveguide arrays by utilizing the anti-$\mathcal{PT}$ symmetry induced by NIM. Numerical simulation about a third-order EP fits well with the coupled-mode theory. A scheme of achieving fourth-order EPs is also discussed. This work highlights the potential of loss-free NIMs in the study of non-Hermitian optics.

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Xin-Zhe Zhang, Li-Ting Wu, Ru-Zhi Luo, Jing Chen. 2023-03-28. Higher-order exceptional points in loss-free waveguide arrays with negative-index materials. https://arxiv.org/abs/2304.07289

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