Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Observation of intrinsic chiral bound states in the continuum

Nature volume 613, pages 474–478 (2023)Cite this article

Subjects

Abstract

Photons with spin angular momentum possess intrinsic chirality, which underpins many phenomena including nonlinear optics1, quantum optics2, topological photonics3 and chiroptics4. Intrinsic chirality is weak in natural materials, and recent theoretical proposals5,6,7 aimed to enlarge circular dichroism by resonant metasurfaces supporting bound states in the continuum that enhance substantially chiral light–matter interactions. Those insightful works resort to three-dimensional sophisticated geometries, which are too challenging to be realized for optical frequencies8. Therefore, most of the experimental attempts9,10,11 showing strong circular dichroism rely on false/extrinsic chirality by using either oblique incidence9,10 or structural anisotropy11. Here we report on the experimental realization of true/intrinsic chiral response with resonant metasurfaces in which the engineered slant geometry breaks both in-plane and out-of-plane symmetries. Our result marks, to our knowledge, the first observation of intrinsic chiral bound states in the continuum with near-unity circular dichroism of 0.93 and a high quality factor exceeding 2,663 for visible frequencies. Our chiral metasurfaces may lead to a plethora of applications in chiral light sources and detectors, chiral sensing, valleytronics and asymmetric photocatalysis.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Origin of intrinsic chirality induced by slant perturbation.
Fig. 2: Design, fabrication and characterization of slant-perturbation metasurfaces.
Fig. 3: Inherent linkage between geometric perturbations for achieving chiral BICs.
Fig. 4: Giant CD and Q-factor enabled by intrinsic chiral BICs.

Similar content being viewed by others

Data availability

The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request. The raw data can be accessed in the repository by the link: https://figshare.com/articles/dataset/Raw_Data_for_Nature_manuscript_2022-05-07139B/21257547.

References

  1. Collins, J. T. et al. First observation of optical activity in hyper-Rayleigh scattering. Phys. Rev. X 9, 011024 (2019).

    CAS  Google Scholar 

  2. Lodahl, P. et al. Chiral quantum optics. Nature 541, 473–480 (2017).

    Article  ADS  CAS  Google Scholar 

  3. Parappurath, N., Alpeggiani, F., Kuipers, L. & Verhagen, E. Direct observation of topological edge states in silicon photonic crystals: spin, dispersion, and chiral routing. Sci. Adv. 6, eaaw4137 (2020).

    Article  ADS  CAS  Google Scholar 

  4. Chen, Y. et al. Multidimensional nanoscopic chiroptics. Nat. Rev. Phys. 4, 113–124 (2021).

    Article  Google Scholar 

  5. Gorkunov, M. V., Antonov, A. A. & Kivshar, Y. S. Metasurfaces with maximum chirality empowered by bound states in the continuum. Phys. Rev. Lett. 125, 093903 (2020).

    Article  ADS  CAS  Google Scholar 

  6. Overvig, A., Yu, N. & Alu, A. Chiral quasi-ound states in the continuum. Phys. Rev. Lett. 126, 073001 (2021).

    Article  ADS  CAS  Google Scholar 

  7. Dixon, J., Lawrence, M., Barton, D. R. & Dionne, J. Self-isolated raman lasing with a chiral dielectric metasurface. Phys. Rev. Lett. 126, 123201 (2021).

    Article  ADS  CAS  Google Scholar 

  8. Gorkunov, M. V., Antonov, A. A., Tuz, V. R., Kupriianov, A. S. & Kivshar, Y. S. Bound states in the continuum underpin near‐lossless maximum chirality in dielectric metasurfaces. Adv. Opt. Mater. 9, 2100797 (2021).

    Article  CAS  Google Scholar 

  9. Liu, W. et al. Circularly polarized states spawning from bound states in the continuum. Phys. Rev. Lett. 123, 116104 (2019).

    Article  ADS  CAS  Google Scholar 

  10. Wu, J. et al. Observation of giant extrinsic chirality empowered by quasi-bound states in the continuum. Phys. Rev. Appl. 16, 064018 (2021).

    Article  ADS  CAS  Google Scholar 

  11. Shi, T. et al. Planar chiral metasurfaces with maximal and tunable chiroptical response driven by bound states in the continuum. Nat. Commun. 13, 4111 (2022).

    Article  ADS  CAS  Google Scholar 

  12. Barron, L. D. Molecular Light Scattering and Optical Activity (Cambridge Univ. Press, 2004).

  13. Fernandez-Corbaton, I., Fruhnert, M. & Rockstuhl, C. Objects of maximum electromagnetic chirality. Phys. Rev. X 6, 031013 (2016).

    Google Scholar 

  14. Wu, C. et al. Spectrally selective chiral silicon metasurfaces based on infrared Fano resonances. Nat. Commun. 5, 3892 (2014).

    Article  ADS  CAS  Google Scholar 

  15. Plum, E., Fedotov, V. A. & Zheludev, N. I. Optical activity in extrinsically chiral metamaterial. Appl. Phys. Lett. 93, 191911 (2008).

    Article  ADS  Google Scholar 

  16. Plum, E. et al. Metamaterials: optical activity without chirality. Phys. Rev. Lett. 102, 113902 (2009).

    Article  ADS  CAS  Google Scholar 

  17. Barron, L. D. True and false chirality and absolute asymmetric synthesis. J. Am. Chem. Soc. 108, 5539–5542 (1986).

    Article  CAS  Google Scholar 

  18. Barron, L. D. True and false chirality and absolute enantioselection. Rend. Lincei 24, 179–189 (2013).

    Article  Google Scholar 

  19. Valev, V. K., Baumberg, J. J., Sibilia, C. & Verbiest, T. Chirality and chiroptical effects in plasmonic nanostructures: fundamentals, recent progress, and outlook. Adv. Mater. 25, 2517–2534 (2013).

    Article  CAS  Google Scholar 

  20. Hentschel, M., Schaferling, M., Duan, X., Giessen, H. & Liu, N. Chiral plasmonics. Sci. Adv. 3, e1602735 (2017).

    Article  ADS  Google Scholar 

  21. Mun, J. et al. Electromagnetic chirality: from fundamentals to nontraditional chiroptical phenomena. Light Sci. Appl. 9, 139 (2020).

    Article  ADS  CAS  Google Scholar 

  22. Hsu, C. W. et al. Observation of trapped light within the radiation continuum. Nature 499, 188–191 (2013).

    Article  ADS  CAS  Google Scholar 

  23. Hsu, C. W., Zhen, B., Stone, A. D., Joannopoulos, J. D. & Soljačić, M. Bound states in the continuum. Nat. Rev. Mater. 1, 16048 (2016).

    Article  ADS  CAS  Google Scholar 

  24. Koshelev, K., Lepeshov, S., Liu, M., Bogdanov, A. & Kivshar, Y. Asymmetric metasurfaces with high-Q resonances governed by bound states in the continuum. Phys. Rev. Lett. 121, 193903 (2018).

    Article  ADS  Google Scholar 

  25. Azzam, S. I., Shalaev, V. M., Boltasseva, A. & Kildishev, A. V. Formation of bound states in the continuum in hybrid plasmonic-photonic systems. Phys. Rev. Lett. 121, 253901 (2018).

    Article  ADS  CAS  Google Scholar 

  26. Liu, Z. et al. High-Q quasibound states in the continuum for nonlinear metasurfaces. Phys. Rev. Lett. 123, 253901 (2019).

    Article  ADS  CAS  Google Scholar 

  27. Yin, X., Jin, J., Soljacic, M., Peng, C. & Zhen, B. Observation of topologically enabled unidirectional guided resonances. Nature 580, 467–471 (2020).

    Article  ADS  CAS  Google Scholar 

  28. Poulikakos, L. V. et al. Optical chirality flux as a useful far-field probe of chiral near fields. ACS Photonics 3, 1619–1625 (2016).

    Article  CAS  Google Scholar 

  29. Cameron, R. P., Barnett, S. M. & Yao, A. M. Optical helicity, optical spin and related quantities in electromagnetic theory. New J. Phys. 14, 053050 (2012).

    Article  ADS  MATH  Google Scholar 

  30. Tang, Y. & Cohen, A. E. Enhanced enantioselectivity in excitation of chiral molecules by superchiral light. Science 332, 333–336 (2011).

    Article  ADS  CAS  Google Scholar 

  31. Taghizadeh, A. & Chung, I. S. Quasi bound states in the continuum with few unit cells of photonic crystal slab. Appl. Phys. Lett. 111, 031114 (2017).

    Article  ADS  Google Scholar 

  32. Hentschel, M. et al. Optical Properties of chiral three-dimensional plasmonic oligomers at the onset of charge-transfer plasmons. ACS Nano 6, 10355–10365 (2012).

    Article  CAS  Google Scholar 

  33. Zhang, S. et al. Photoinduced handedness switching in terahertz chiral metamolecules. Nat. Commun. 3, 942 (2012).

    Article  ADS  Google Scholar 

  34. Cui, Y., Kang, L., Lan, S., Rodrigues, S. & Cai, W. Giant chiral optical response from a twisted-arc metamaterial. Nano Lett. 14, 1021–1025 (2014).

    Article  ADS  CAS  Google Scholar 

  35. Chen, Y., Gao, J. & Yang, X. Chiral metamaterials of plasmonic slanted nanoapertures with symmetry breaking. Nano Lett. 18, 520–527 (2018).

    Article  ADS  CAS  Google Scholar 

  36. Wu, Z., Chen, X., Wang, M., Dong, J. & Zheng, Y. High-performance ultrathin active chiral metamaterials. ACS Nano 12, 5030–5041 (2018).

    Article  CAS  Google Scholar 

  37. Yang, S. et al. Spin-selective transmission in chiral folded metasurfaces. Nano Lett. 19, 3432–3439 (2019).

    Article  ADS  CAS  Google Scholar 

  38. Semnani, B., Flannery, J., Al Maruf, R. & Bajcsy, M. Spin-preserving chiral photonic crystal mirror. Light Sci. Appl. 9, 23 (2020).

    Article  ADS  CAS  Google Scholar 

  39. Zhu, A. Y. et al. Giant intrinsic chiro-optical activity in planar dielectric nanostructures. Light Sci. Appl. 7, 17158 (2018).

    Article  CAS  Google Scholar 

  40. Ji, C.-Y. et al. Artificial propeller chirality and counterintuitive reversal of circular dichroism in twisted meta-molecules. Nano Lett. 21, 6828–6834 (2021).

    Article  ADS  CAS  Google Scholar 

Download references

Acknowledgements

S.X. acknowledges support from the National Key Research and Development Project (grant no. 2021YFA1400802). Y.C. acknowledges support from the National Natural Science Foundation of China (No. 62275241) and the CAS Talents Programme. D.W. acknowledges support from the National Natural Science Foundation of China (grant no. 61927814). C.-W.Q. acknowledges financial support from the National Research Foundation, Prime Minister’s Office, Singapore under the Competitive Research Programme Award NRF-CRP22-2019-0006. C.-W.Q. is also supported by a grant (no. R-261-518-004-720| A-0005947-16-00) from the Advanced Research and Technology Innovation Centre from the National University of Singapore.

Author information

Author notes

  1. These authors contributed equally: Yang Chen, Huachun Deng, Xinbo Sha, Weijin Chen

Authors and Affiliations

  1. Chinese Academy of Sciences Key Laboratory of Mechanical Behavior and Design of Materials, Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, China

    Yang Chen, Ruize Wang, Yu-Hang Chen, Dong Wu & Jiaru Chu

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

    Yang Chen, Weijin Chen & Cheng-Wei Qiu

  3. Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System, Harbin Institute of Technology, Shenzhen, P. R. China

    Huachun Deng, Xinbo Sha & Shumin Xiao

  4. Nonlinear Physics Center, Research School of Physics, Australian National University, Canberra, New South Wales, Australia

    Yuri S. Kivshar

  5. Pengcheng Laboratory, Shenzhen, P. R. China

    Shumin Xiao

Authors
  1. Yang Chen
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Huachun Deng
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Xinbo Sha
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Weijin Chen
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Ruize Wang
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Yu-Hang Chen
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Dong Wu
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Jiaru Chu
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. Yuri S. Kivshar
    View author publications

    You can also search for this author in PubMed Google Scholar

  10. Shumin Xiao
    View author publications

    You can also search for this author in PubMed Google Scholar

  11. Cheng-Wei Qiu
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

Y.C., S.X. and C.-W.Q. conceived the idea and designed the experiments. S.X. and C.-W.Q. supervised the project. Y.C. and W.C. conducted the simulations and theoretical analysis. H.D. and X.S. performed the experiments. Y.C., R.W., Y.-H.C., D.W., J.C., Y.S.K., S.X. and C.-W.Q analysed the data. Y.C. drafted the paper with inputs from all authors.

Corresponding authors

Correspondence to Shumin Xiao or Cheng-Wei Qiu.

Ethics declarations

Competing interests

The authors declare no competing interests.

Peer review

Peer review information

Nature thanks the anonymous reviewers for their contribution to the peer review of this work.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data figures and tables

Supplementary information

Supplementary Information

Supplementary Figs. 1–15 and Sections 1–13.

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Chen, Y., Deng, H., Sha, X. et al. Observation of intrinsic chiral bound states in the continuum. Nature 613, 474–478 (2023). https://doi.org/10.1038/s41586-022-05467-6

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41586-022-05467-6

This article is cited by

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing