Letter | Published:

Correlated fluorescence blinking in two-dimensional semiconductor heterostructures

Nature volume 541, pages 6267 (05 January 2017) | Download Citation

Abstract

‘Blinking’, or ‘fluorescence intermittency’, refers to a random switching between ‘ON’ (bright) and ‘OFF’ (dark) states of an emitter; it has been studied widely in zero-dimensional quantum dots1 and molecules2,3, and scarcely in one-dimensional systems4,5. A generally accepted mechanism for blinking in quantum dots involves random switching between neutral and charged states6,7 (or is accompanied by fluctuations in charge-carrier traps8), which substantially alters the dynamics of radiative and non-radiative decay. Here, we uncover a new type of blinking effect in vertically stacked, two-dimensional semiconductor heterostructures9, which consist of two distinct monolayers of transition metal dichalcogenides (TMDs) that are weakly coupled by van der Waals forces. Unlike zero-dimensional or one-dimensional systems, two-dimensional TMD heterostructures show a correlated blinking effect, comprising randomly switching bright, neutral and dark states. Fluorescence cross-correlation spectroscopy analyses show that a bright state occurring in one monolayer will simultaneously lead to a dark state in the other monolayer, owing to an intermittent interlayer carrier-transfer process. Our findings suggest that bilayer van der Waals heterostructures provide unique platforms for the study of charge-transfer dynamics and non-equilibrium-state physics, and could see application as correlated light emitters in quantum technology.

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References

  1. 1.

    et al. Fluorescence intermittency in single cadmium selenide nanocrystals. Nature 383, 802–804 (1996)

  2. 2.

    , , & On/off blinking and switching behaviour of single molecules of green fluorescent protein. Nature 388, 355–358 (1997)

  3. 3.

    et al. Discrete intensity jumps and intramolecular electronic energy transfer in the spectroscopy of single conjugated polymer molecules. Science 277, 1074–1077 (1997)

  4. 4.

    , , & Universal emission intermittency in quantum dots, nanorods and nanowires. Nat. Phys. 4, 519–522 (2008)

  5. 5.

    , & Spatial and intensity modulation of nanowire emission induced by mobile charges. J. Am. Chem. Soc. 129, 13160–13171 (2007)

  6. 6.

    & Random telegraph signal in the photoluminescence intensity of a single quantum dot. Phys. Rev. Lett. 78, 1110–1113 (1997)

  7. 7.

    & Origin and control of blinking in quantum dots. Nat. Nanotechnol. 11, 661–671 (2016)

  8. 8.

    et al. Two types of luminescence blinking revealed by spectroelectrochemistry of single quantum dots. Nature 479, 203–207 (2011)

  9. 9.

    & Van der Waals heterostructures. Nature 499, 419–425 (2013)

  10. 10.

    et al. Non-blinking quantum dot with a plasmonic nanoshell resonator. Nat. Nanotechnol. 10, 170–175 (2015)

  11. 11.

    , & Transient fluorescence of the off state in blinking CdSe/CdS/ZnS semiconductor nanocrystals is not governed by Auger recombination. Phys. Rev. Lett. 104, 157404 (2010)

  12. 12.

    , , & Challenge to the charging model of semiconductor-nanocrystal fluorescence intermittency from off-state quantum yields and multiexciton blinking. Phys. Rev. Lett. 104, 157403 (2010)

  13. 13.

    , , , & Coupled spin and valley physics in monolayers of MoS2 and other group-VI dichalcogenides. Phys. Rev. Lett. 108, 196802 (2012)

  14. 14.

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

  15. 15.

    et al. Electrical control of neutral and charged excitons in a monolayer semiconductor. Nat. Commun. 4, 1474 (2013)

  16. 16.

    et al. Nonblinking, intense two-dimensional light emitter: monolayer WS2 triangles. ACS Nano 7, 10985–10994 (2013)

  17. 17.

    et al. Field-effect tunneling transistor based on vertical graphene heterostructures. Science 335, 947–950 (2012)

  18. 18.

    et al. Light-emitting diodes by band-structure engineering in van der Waals heterostructures. Nat. Mater. 14, 301–306 (2015)

  19. 19.

    et al. Observation of long-lived interlayer excitons in monolayer MoSe2-WSe2 heterostructures. Nat. Commun. 6, 6242 (2015)

  20. 20.

    et al. Valley-polarized exciton dynamics in a 2D semiconductor heterostructure. Science 351, 688–691 (2016)

  21. 21.

    , , & Auger recombination of biexcitons and negative and positive trions in individual quantum dots. ACS Nano 8, 7288–7296 (2014)

  22. 22.

    et al. Multistate blinking and scaling of recombination rates in individual silica-coated CdSe/CdS nanocrystals. ACS Photonics 2, 1505–1512 (2015)

  23. 23.

    et al. Interlayer breathing and shear modes in few-trilayer MoS2 and WSe2. Nano Lett. 13, 1007–1015 (2013)

  24. 24.

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

  25. 25.

    et al. Observation of interlayer phonon modes in van der Waals heterostructures. Phys. Rev. B 91, 165403 (2015)

  26. 26.

    et al. Tuning interlayer coupling in large-area heterostructures with CVD-grown MoS2 and WS2 monolayers. Nano Lett. 14, 3185–3190 (2014)

  27. 27.

    et al. Equally efficient inter layer exciton relaxation and improved absorption in epitaxial and nonepitaxial MoS2/WS2 heterostructures. Nano Lett. 15, 486–491 (2015)

  28. 28.

    Fluorescence Resonance Energy Transfer (Wiley-VCH, 2008)

  29. 29.

    , & Fluorescence correlation spectroscopy of triplet states in solution: a theoretical and experimental study. J. Phys. Chem. 99, 13368–13379 (1995)

  30. 30.

    , & Model of fluorescence intermittency of single colloidal semiconductor quantum dots using multiple recombination centers. Phys. Rev. Lett. 103, 207402 (2009)

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Acknowledgements

We thank Professor C.-D. Ohl for providing us with a high-speed camera for dynamical fluorescence imaging. Q.X. acknowledges the support of the Singapore National Research Foundation through an Investigatorship award (NRF-NRFI2015-03), and the Singapore Ministry of Education via two AcRF Tier 2 grants (MOE2012-T2-2-086 and MOE2015-T2-1-047). W.L. acknowledges scholarship support from the China Scholarship Council (no. 201506160035).

Author information

Affiliations

  1. Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 637371 Singapore

    • Weigao Xu
    • , Weiwei Liu
    • , Weijie Zhao
    • , Xin Lu
    • , Weibo Gao
    •  & Qihua Xiong
  2. Department of Physics and Center for Applied Photonics, University of Konstanz, D-78457 Konstanz, Germany

    • Jan F. Schmidt
    • , Timo Raab
    •  & Denis V. Seletskiy
  3. Laboratoire Pierre Aigrain, Ecole Normale Supérieure, PSL Research University, CNRS, Université Pierre et Marie Curie, Sorbonne Universités, Université Paris Diderot, Sorbonne Paris-Cité, 24 Rue Lhomond, 75231 Paris Cedex 05, France

    • Carole Diederichs
  4. MajuLab, CNRS–UNS–NUS–NTU International Joint Research Unit, UMI 3654 Singapore

    • Carole Diederichs
    •  & Qihua Xiong
  5. NOVITAS, Nanoelectronics Center of Excellence, School of Electrical and Electronic Engineering, Nanyang Technological University, 639798 Singapore

    • Qihua Xiong

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Contributions

W.X. and Q.X. designed the research; W.X., W.L. and X.L. prepared the heterostructures and carried out steady-state/transient fluorescence spectroscopy measurements and correlation measurements; J.F.S., W.Z., T.R. and D.V.S. performed transient absorption spectroscopy measurements; W.X., W.L., X.L., W.Z., J.F.S., D.V.S., C.D., W.G. and Q.X. analysed the data; and W.X., W.L. and Q.X. wrote the manuscript. All authors commented on the manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Qihua Xiong.

Reviewer Information Nature thanks X. Cui and A. Malko for their contribution to the peer review of this work.

Supplementary information

PDF files

  1. 1.

    Supplementary Information

    This file contains Supplementary Text, Supplementary Figures 1-16 and Supplementary References.

Videos

  1. 1.

    High speed dynamic fluorescence imaging of the WS2 component in the WS2/MoSe2 heterostructure

    High speed dynamic fluorescence imaging of the WS2 component in the WS2/MoSe2 heterostructure.

  2. 2.

    High speed dynamic fluorescence imaging of the MoSe2 component in the WS2/MoSe2 heterostructure

    High speed dynamic fluorescence imaging of the MoSe2 component in the WS2/MoSe2 heterostructure.

  3. 3.

    Dynamic fluorescence imaging of the WS2 component in a MoS2/WS2 heterostructure acquired with a color CCD camera

    Dynamic fluorescence imaging of the WS2 component in a MoS2/WS2 heterostructure acquired with a color CCD camera.

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DOI

https://doi.org/10.1038/nature20601

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