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arXiv · 2411.04698

Robust multimode interference and conversion in topological unidirectional surface magnetoplasmons

Chao Liu·Ziyang Zhao·Tianjing Guo·Jie Xu·Xiaohua Deng·Kai Yuan·Rongxin Tang·Kosmas L. Tsakmakidis·Lujun Hong
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Abstract

We have theoretically investigated surface magnetoplasmons (SMPs) in a yttrium-iron-garnet (YIG) sandwiched waveguide. The dispersion demonstated that this waveguide can support topological unidirectional SMPs. Based on unidirectional SMPs, magnetically controllable multimode interference (MMI) is verified in both symmetric and asymmetric waveguides. Due to the coupling between the modes along two YIG-air interfaces, the asymmetric waveguide supports a unidirectional even mode within a single-mode frequency range. Moreover, these modes are topological protected when disorder is introduced. Utilizing robust unidirectional SMPs MMI (USMMI), tunable splitters have been achieved. It has been demonstrated that mode conversion between different modes can be realized. These results provide many degrees of freedom to manipulate topological waves.

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Chao Liu, Ziyang Zhao, Tianjing Guo, Jie Xu, Xiaohua Deng, Kai Yuan, Rongxin Tang, Kosmas L. Tsakmakidis, Lujun Hong. 2024-11-07. Robust multimode interference and conversion in topological unidirectional surface magnetoplasmons. https://arxiv.org/abs/2411.04698

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