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Photonic exceptional points in engineered materials and their emerging applications

Nature Reviews Materials (2026)Cite this article

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Abstract

Enabled by the coalescence of eigenvalues and eigenstates, exceptional points (EPs) in non-Hermitian photonic systems have revolutionized the control of light–matter interactions and sparked growing interest across diverse material and structural platforms. This Review synthesizes advances in engineered materials that harness EPs across three key domains: band EPs in dielectric photonic crystals, wherein radiation-induced loss transforms Hermitian degeneracies into exceptional rings and bulk Fermi arcs; scattering EPs in hybrid dielectric or lossy metasurfaces, enabling unidirectional reflectionless propagation; and Jones EPs in plasmonic and anisotropic materials, which exploit chiral degeneracies for asymmetric scattering and holographic multiplexing. We highlight emerging phenomena in dynamic EP control using tunable materials such as graphene, phase-change media and micro-electromechanical systems, which enable real-time modulation, topological phase transitions and the direct observation of non-Hermitian braiding. The topological properties of EPs, manifested in phase accumulation and half-integer polarization charges, support key applications in wavefront shaping and singular optics. New frontiers involve the integration of EPs with other concepts, including bound states in the continuum, Dirac points, nonreciprocity and magnetic tunability. Bridging non-Hermitian physics with material-engineered platforms paves the way for adaptive photonic devices, topological meta-architectures and machine learning-driven designs, charting a path towards next-generation nanophotonics.

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Fig. 1: Photonic EPs in engineered materials and their emerging applications.
Fig. 2: Band EPs.
Fig. 3: Scattering EPs.
Fig. 4: Jones EPs.
Fig. 5: Dynamic control and braiding of EP.
Fig. 6: Topological properties and wavefront engineering of EPs.
Fig. 7: Special EPs and new frontiers.

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Acknowledgements

H.Q. and Z.Z. thank J. Wang and Q. Chen for the helpful discussions. C.-W.Q. acknowledges the financial support of the Ministry of Education, Republic of Singapore (grant numbers A-8002152-00-00, A-8002458-00-00 and A-8003643-00-00), and the Competitive Research Program Award (NRF-CRP26-2021-0004 and NRF-CRP30-2023-0003) from the National Research Foundation, Prime Minister’s Office, Singapore. Q.S. acknowledges funding support from the National Natural Science Foundation of China (no. 12474388) and the Guangdong Basic and Applied Basic Research Foundation (no. 2025A1515011483).

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  1. These authors contributed equally: Haoye Qin, Wenjing Lv.

Authors and Affiliations

  1. Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore

    Haoye Qin & Cheng-Wei Qiu

  2. Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, China

    Wenjing Lv, Zijin Yang, Jue Li, Mengyao Li, Bo Li & Qinghua Song

  3. Laboratory of Wave Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland

    Zhe Zhang & Romain Fleury

  4. School of Materials Science and Engineering, Tsinghua University, Beijing, China

    Ji Zhou

  5. Department of Physics, Colorado School of Mines, Golden, CO, USA

    Patrice Genevet

  6. Department of Physics, National University of Singapore, Singapore, Singapore

    Cheng-Wei Qiu

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Contributions

C.-W.Q., P.G., R.F., H.Q., Q.S., B.L. and J.Z. discussed the content of the Review. H.Q., W.L., Z.Z., M.L., Z.Y., J.L. and Q.S. wrote the first draft. All authors reviewed and edited the final manuscript.

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Correspondence to Romain Fleury, Patrice Genevet, Qinghua Song or Cheng-Wei Qiu.

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Qin, H., Lv, W., Zhang, Z. et al. Photonic exceptional points in engineered materials and their emerging applications. Nat Rev Mater (2026). https://doi.org/10.1038/s41578-026-00896-5

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