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arXiv · 2502.17649

Hybridization of Non-Hermitian Topological Interface Modes

Yuhao Wang·Hai-Chau Nguyen·Zhiyi Yuan·T. Thu Ha Do·Vytautas Valuckas·Hai Son Nguyen·Cuong Dang·Son Tung Ha
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Abstract

We propose and experimentally demonstrate the hybridization of radiating topological interface states, analogous to Jackiw-Rebbi states but in gain media with radiation fields. This hybridization not only modifies energy levels under a strong coupling scheme but also significantly reshapes far-field radiation characteristics. The bonding mode exhibits sub-radiant, omnidirectional emission, while the antibonding mode becomes super-radiant and highly unidirectional. Crucially, this non-Hermitian hybridization is tunable, allowing simultaneous control of energy splitting, quality factor, and far-field radiation by varying the distance between the two topological interfaces. Our findings establish hybridized radiating topological interface states as a robust platform for engineering two-level systems with tailored far-field responses, offering new possibilities for applications in beam shaping, nonlinear optics, quantum technologies, and beyond.

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Yuhao Wang, Hai-Chau Nguyen, Zhiyi Yuan, T. Thu Ha Do, Vytautas Valuckas, Hai Son Nguyen, Cuong Dang, Son Tung Ha. 2025-02-24. Hybridization of Non-Hermitian Topological Interface Modes. https://arxiv.org/abs/2502.17649

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