Realization of a three-dimensional photonic higher-order topological insulator
The discovery of photonic higher-order topological insulators (HOTIs) has expanded our understanding of band topology, offering robust lower-dimensional boundary states for photonic devices. However, realizing three-dimensional (3D) photonic HOTIs remains challenging due to the vectorial and leaky nature of electromagnetic waves. Here, we present the experimental realization of a 3D Wannier-type photonic HOTI using a tight-binding-like metal-cage photonic crystal, whose band structures align with a 3D tight-binding model via confined Mie resonances. Microwave near-field measurements reveal coexisting topological surface, hinge, and corner states in a single 3D photonic HOTI, consistent with theoretical predictions. Remarkably, these states are robust and self-guided even within the light cone continuum, functioning without ancillary cladding. This work paves the way for multi-dimensional manipulation of electromagnetic waves on 3D cladding-free photonic bandgap materials, enabling practical applications in 3D topological integrated photonic devices.
Authors
- Zhenxiao Zhu (ORCID: https://orcid.org/0000-0003-3868-2708)
- Biye Xie (ORCID: https://orcid.org/0000-0001-7258-8913)
- Yan Meng (ORCID: https://orcid.org/0000-0002-1387-1644)
- Xiao Tao (ORCID: https://orcid.org/0000-0002-9381-7903)
- Gui-Geng Liu (ORCID: https://orcid.org/0000-0003-4328-9142)
- Zhen Gao (ORCID: https://orcid.org/0000-0001-8284-7958)
- Jingming Chen (ORCID: https://orcid.org/0000-0003-2375-246X)
- Linyun Yang (ORCID: https://orcid.org/0000-0001-8079-5779)
- Perry Ping Shum (ORCID: https://orcid.org/0000-0003-1391-4736)
- Bei Yan (ORCID: https://orcid.org/0000-0002-7571-7810)
- Xiang Xi (ORCID: https://orcid.org/0000-0002-4715-4352)
- Dong Zhao (ORCID: https://orcid.org/0000-0002-7337-9168)
- Ziyao Wang (ORCID: https://orcid.org/0000-0003-0195-1038)
- Hongsheng Chen (ORCID: https://orcid.org/0000-0002-5735-9781)
- Yihao Yang (ORCID: https://orcid.org/0000-0002-4287-0130)
- Minqi Cheng
Institutions
- Chongqing University (CN)
- Dongguan University of Technology (CN)
- Southern University of Science and Technology (CN)
- Westlake University (CN)
- Chinese University of Hong Kong, Shenzhen (CN)
- State Key Laboratory of Chemical Engineering (CN)
- Wuhan University of Science and Technology (CN)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-04-01
- DOI
- https://doi.org/10.1038/s41467-025-58051-7
- Citations
- 16
- Primary Topic
- Topological Materials and Phenomena
- Type
- article
- Field-Weighted Citation Impact
- 19.95
Funders
- National Natural Science Foundation of China
- Science, Technology and Innovation Commission of Shenzhen Municipality
- Basic and Applied Basic Research Foundation of Guangdong Province