Anisotropic strong coupling between two propagating polariton modes
Interface polaritons offer extreme electromagnetic confinement and enhanced light–matter interactions. Although polaritonic strong coupling has been extensively studied, it has largely been confined to isotropic systems with limited coupling strength and tunability. Here, we demonstrate anisotropic strong coupling between hyperbolic volume polaritons and isotropic surface polaritons in cavity-free van der Waals heterostructures. Through near-field nano-imaging and nano-spectroscopy, we directly observe anisotropic strong coupling with normalized coupling strength up to 16.4 ± 1.4, which can be well-described by the multimode Hopfield model. The coupling characteristics are further controlled by adjusting the material thickness and interlayer separation, culminating in epsilon-near-zero strong coupling. These results establish a paradigm for manipulating strong light–matter interactions at the nanoscale, with promising implications for molecular orientation sensing, on-chip optical routing, and directional nanolasing. Various material systems exhibit coupling between distinct classes of polaritons. Here, the authors demonstrate anisotropic strong coupling between hyperbolic volume polaritons and isotropic surface polaritons in α-MoO3/AlN heterostructures.
Authors
- Huaping Wang (ORCID: https://orcid.org/0000-0003-0993-9025)
- Sihao Xia (ORCID: https://orcid.org/0000-0001-7760-8952)
- Bin Zheng (ORCID: https://orcid.org/0000-0002-9636-7311)
- Xingyu Tang
- Zhepeng Zhang (ORCID: https://orcid.org/0000-0002-9870-0720)
- Zelong Fan (ORCID: https://orcid.org/0000-0002-8811-3872)
- Kostya S. Novoselov (ORCID: https://orcid.org/0000-0003-4972-5371)
- Zhiwei He (ORCID: https://orcid.org/0000-0002-3251-8731)
- Honglei Wu (ORCID: https://orcid.org/0000-0002-8852-3951)
- Zhenhua Sun (ORCID: https://orcid.org/0000-0002-9227-6738)
- Youning Gong (ORCID: https://orcid.org/0000-0002-8114-8095)
- Song Han (ORCID: https://orcid.org/0000-0001-7138-4214)
- Wenliang Li (ORCID: https://orcid.org/0000-0001-9452-4347)
- Yupeng Zhang (ORCID: https://orcid.org/0000-0003-2351-5579)
- Hongsheng Chen (ORCID: https://orcid.org/0000-0002-5735-9781)
- Guo Ping Wang (ORCID: https://orcid.org/0000-0002-0607-1323)
- Yingjie Wu (ORCID: https://orcid.org/0000-0001-8326-4973)
- Zhenyang Cui
Institutions
- Zhejiang Normal University (CN)
- National University of Singapore (SG)
- Shenzhen University (CN)
- Zhejiang Lab (CN)
- Zhejiang Academy of Forestry (CN)
- Zhejiang University (CN)
Publication Details
- Journal
- Nature Communications
- Published
- 2026-08-20
- DOI
- https://doi.org/10.1038/s41467-026-77007-z
- Primary Topic
- Strong Light-Matter Interactions
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Ministry of Education - Singapore
- National Natural Science Foundation of China
- Zhejiang University
- Fundamental Research Funds for the Central Universities
- Basic and Applied Basic Research Foundation of Guangdong Province
- Natural Science Foundation of Zhejiang Province