Skip to main content

Thank you for visiting 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.

  • Letter
  • Published:

Observation of moiré excitons in WSe2/WS2 heterostructure superlattices

An Author Correction to this article was published on 08 May 2019

This article has been updated


Moiré superlattices enable the generation of new quantum phenomena in two-dimensional heterostructures, in which the interactions between the atomically thin layers qualitatively change the electronic band structure of the superlattice. For example, mini-Dirac points, tunable Mott insulator states and the Hofstadter butterfly pattern can emerge in different types of graphene/boron nitride moiré superlattices, whereas correlated insulating states and superconductivity have been reported in twisted bilayer graphene moiré superlattices1,2,3,4,5,6,7,8,9,10,11,12. In addition to their pronounced effects on single-particle states, moiré superlattices have recently been predicted to host excited states such as moiré exciton bands13,14,15. Here we report the observation of moiré superlattice exciton states in tungsten diselenide/tungsten disulfide (WSe2/WS2) heterostructures in which the layers are closely aligned. These moiré exciton states manifest as multiple emergent peaks around the original WSe2 A exciton resonance in the absorption spectra, and they exhibit gate dependences that are distinct from that of the A exciton in WSe2 monolayers and in WSe2/WS2 heterostructures with large twist angles. These phenomena can be described by a theoretical model in which the periodic moiré potential is much stronger than the exciton kinetic energy and generates multiple flat exciton minibands. The moiré exciton bands provide an attractive platform from which to explore and control excited states of matter, such as topological excitons and a correlated exciton Hubbard model, in transition-metal dichalcogenides.

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

Access options

Buy this article

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

Fig. 1: Moiré superlattice in a WSe2/WS2 heterostructure with a twist angle close to zero.
Fig. 2: Moiré exciton states in a WSe2/WS2 moiré superlattice.
Fig. 3: Doping dependence of the moiré exciton resonances.
Fig. 4: Moiré excitons in the strong-coupling regime.

Similar content being viewed by others

Data availability

The data that support the findings of this study are available from the corresponding author upon reasonable request.

Change history

  • 08 May 2019

    Change history: In this Letter, the following text has been added to the Acknowledgements section: “the scanning transmission electron microscopy measurements at the Molecular Foundry were supported by the Office of Science, Office of Basic Energy Sciences, of the US Department of Energy under contract number DE-AC02-05CH11231”. See accompanying Amendment.


  1. Hunt, B. et al. Massive Dirac fermions and Hofstadter butterfly in a van der Waals heterostructure. Science 340, 1427–1430 (2013).

    Article  ADS  CAS  Google Scholar 

  2. Ponomarenko, L. A. et al. Cloning of Dirac fermions in graphene superlattices. Nature 497, 594–597 (2013).

    Article  ADS  CAS  Google Scholar 

  3. Dean, C. R. et al. Hofstadter’s butterfly and the fractal quantum Hall effect in moiré superlattices. Nature 497, 598–602 (2013).

    Article  ADS  CAS  Google Scholar 

  4. Cao, Y. et al. Unconventional superconductivity in magic-angle graphene superlattices. Nature 556, 43–50 (2018).

    Article  ADS  CAS  Google Scholar 

  5. Cao, Y. et al. Correlated insulator behaviour at half-filling in magic-angle graphene superlattices. Nature 556, 80–84 (2018).

    Article  ADS  CAS  Google Scholar 

  6. Chen, G. et al. Gate-tunable mott insulator in trilayer graphene-boron nitride moiré superlattice. Preprint at (2018).

  7. Shi, Z. W. et al. Gate-dependent pseudospin mixing in graphene/boron nitride moire superlattices. Nat. Phys. 10, 743–747 (2014).

    Article  CAS  Google Scholar 

  8. Spanton, E. M. et al. Observation of fractional Chern insulators in a van der Waals heterostructure. Science 360, 62–66 (2018).

    Article  ADS  CAS  Google Scholar 

  9. Wallbank, J. R., Patel, A. A., Mucha-Kruczynski, M., Geim, A. K. & Falko, V. I. Generic miniband structure of graphene on a hexagonal substrate. Phys. Rev. B 87, 245408 (2013).

    Article  ADS  Google Scholar 

  10. Song, J. C. W., Samutpraphoot, P. & Levitov, L. S. Topological Bloch bands in graphene superlattices. Proc. Natl Acad. Sci. USA 112, 10879–10883 (2015).

    Article  ADS  MathSciNet  CAS  Google Scholar 

  11. Gorbachev, R. V. et al. Detecting topological currents in graphene superlattices. Science 346, 448–451 (2014).

    Article  ADS  CAS  Google Scholar 

  12. Lee, M. et al. Ballistic miniband conduction in a graphene superlattice. Science 353, 1526–1529 (2016).

    Article  ADS  CAS  Google Scholar 

  13. Wu, F., Lovorn, T. & MacDonald, A. H. Topological exciton bands in moiré heterojunctions. Phys. Rev. Lett. 118, 147401 (2017).

    Article  ADS  Google Scholar 

  14. Yu, H., Liu, G. B., Tang, J., Xu, X. & Yao, W. Moiré excitons: From programmable quantum emitter arrays to spin–orbit-coupled artificial lattices. Sci. Adv. 3, e1701696 (2017).

    Article  ADS  Google Scholar 

  15. Wu, F. C., Lovorn, T. & MacDonald, A. H. Theory of optical absorption by interlayer excitons in transition metal dichalcogenide heterobilayers. Phys. Rev. B 97, 035306 (2018).

    Article  ADS  CAS  Google Scholar 

  16. Chernikov, A. et al. Exciton binding energy and nonhydrogenic Rydberg series in monolayer WS2. Phys. Rev. Lett. 113, 076802 (2014).

    Article  ADS  Google Scholar 

  17. Ye, Z. et al. Probing excitonic dark states in single-layer tungsten disulphide. Nature 513, 214–218 (2014).

    Article  ADS  CAS  Google Scholar 

  18. Greiner, M., Mandel, O., Esslinger, T., Hänsch, T. W. & Bloch, I. Quantum phase transition from a superfluid to a Mott insulator in a gas of ultracold atoms. Nature 415, 39–44 (2002).

    Article  ADS  CAS  Google Scholar 

  19. Fisher, M. P. A., Weichman, P. B., Grinstein, G. & Fisher, D. S. Boson localization and the superfluid-insulator transition. Phys. Rev. B 40, 546–570 (1989).

    Article  ADS  CAS  Google Scholar 

  20. Schutte, W. J., Deboer, J. L. & Jellinek, F. Crystal structures of tungsten disulfide and diselenide. J. Solid State Chem. 70, 207–209 (1987).

    Article  ADS  CAS  Google Scholar 

  21. Zhang, C. et al. Interlayer couplings, Moiré patterns, and 2D electronic superlattices in MoS2/WSe2 hetero-bilayers. Sci. Adv. 3, e1601459 (2017).

    Article  ADS  Google Scholar 

  22. Pan, Y. et al. Quantum-confined electronic states arising from the moiré pattern of MoS2–WSe2 heterobilayers. Nano Lett. 18, 1849–1855 (2018).

    Article  ADS  CAS  Google Scholar 

  23. Hong, X. et al. Ultrafast charge transfer in atomically thin MoS2/WS2 heterostructures. Nat. Nanotechnol. 9, 682–686 (2014).

    Article  ADS  CAS  Google Scholar 

  24. Wang, K. et al. Interlayer coupling in twisted WSe2/WS2 bilayer heterostructures revealed by optical spectroscopy. ACS Nano 10, 6612–6622 (2016).

    Article  CAS  Google Scholar 

  25. Kang, J., Tongay, S., Zhou, J., Li, J. B. & Wu, J. Q. Band offsets and heterostructures of two-dimensional semiconductors. Appl. Phys. Lett. 102, 012111 (2013).

    Article  ADS  Google Scholar 

  26. Jin, C. et al. Imaging of pure spin-valley diffusion current in WS2-WSe2 heterostructures. Science 360, 893–896 (2018).

    Article  ADS  CAS  Google Scholar 

  27. Wang, F. et al. Interactions between individual carbon nanotubes studied by Rayleigh scattering spectroscopy. Phys. Rev. Lett. 96, 167401 (2006).

    Article  ADS  Google Scholar 

  28. Raja, A. et al. Coulomb engineering of the bandgap and excitons in two-dimensional materials. Nat. Commun. 8, 15251 (2017).

    Article  ADS  Google Scholar 

  29. Mak, K. F. et al. Tightly bound trions in monolayer MoS2. Nat. Mater. 12, 207–211 (2013).

    Article  ADS  CAS  Google Scholar 

  30. Yu, H., Liu, G. B., Gong, P., Xu, X. & Yao, W. Dirac cones and Dirac saddle points of bright excitons in monolayer transition metal dichalcogenides. Nat. Commun. 5, 3876 (2014).

    Article  CAS  Google Scholar 

  31. Wang, L. et al. One-dimensional electrical contact to a two-dimensional material. Science 342, 614–617 (2013).

    Article  ADS  CAS  Google Scholar 

Download references


We acknowledge helpful discussions with A. Macdonald, F. Wu and S. Kahn, as well as technical support from J. Ciston on scanning transmission electron microscopy measurements. This work was supported primarily by the Director, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division of the US Department of Energy under contract number DE-AC02-05CH11231 (van der Waals heterostructures program, KCWF16). The device fabrication was supported by the NSF EFRI program (EFMA-1542741); photoluminescence excitation spectroscopy of the heterostructure by the US Army Research Office under MURI award W911NF-17-1-0312; the scanning transmission electron microscopy measurements at the Molecular Foundry were supported by the Office of Science, Office of Basic Energy Sciences, of the US Department of Energy under contract number DE-AC02-05CH11231; and the growth of hexagonal boron nitride crystals by the Elemental Strategy Initiative conducted by the MEXT, Japan and JSPS KAKENHI (grant number JP15K21722). S.T. acknowledges support from NSF DMR 1552220 NSF CAREER award for the growth of WS2 and WSe2 crystals, and E.C.R. acknowledges support from the Department of Defense (DoD) through the National Defense Science & Engineering Graduate Fellowship (NDSEG) Program.

Reviewer information

Nature thanks Vladimir Falko and the other anonymous reviewer(s) for their contribution to the peer review of this work.

Author information

Authors and Affiliations



F.W. and C.J. conceived the research. C.J., E.C.R. and D.W. carried out optical measurements. A.Y. and A.Z. performed electron microscopy measurements. C.J., F.W., E.C.R. and D.W. performed theoretical analysis. E.C.R., M.I.B.U., D.W., S.Z., Z.Z. and S.S fabricated van der Waals heterostructures. Y.Q., S.Y. and S.T. grew WSe2 and WS2 crystals. K.W. and T.T. grew hexagonal boron nitride crystals. All authors discussed the results and wrote the manuscript.

Corresponding author

Correspondence to Feng Wang.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

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

Supplementary information

Supplementary Information

This file contains Supplementary Information Sections 1-12, which includes Supplementary Figures 1-10 and additional references.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Jin, C., Regan, E.C., Yan, A. et al. Observation of moiré excitons in WSe2/WS2 heterostructure superlattices. Nature 567, 76–80 (2019).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

This article is cited by


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.


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