Deterministic coupling of site-controlled quantum emitters in monolayer WSe2 to plasmonic nanocavities


Solid-state single-quantum emitters are crucial resources for on-chip photonic quantum technologies and require efficient cavity–emitter coupling to realize quantum networks beyond the single-node level1,2. Monolayer WSe2, a transition metal dichalcogenide semiconductor, can host randomly located quantum emitters3,4,5,6, while nanobubbles7 as well as lithographically defined arrays of pillars in contact with the transition metal dichalcogenide act as spatially controlled stressors8,9. The induced strain can then create excitons at defined locations. This ability to create zero-dimensional (0D) excitons anywhere within a 2D material is promising for the development of scalable quantum technologies, but so far lacks mature cavity integration and suffers from low emitter quantum yields. Here we demonstrate a deterministic approach to achieve Purcell enhancement at lithographically defined locations using the sharp corners of a metal nanocube for both electric field enhancement and to deform a 2D material. This nanoplasmonic platform allows the study of the same quantum emitter before and after coupling. For a 3 × 4 array of quantum emitters we show Purcell factors of up to 551 (average of 181), single-photon emission rates of up to 42 MHz and a narrow exciton linewidth as low as 55 μeV. Furthermore, the use of flux-grown WSe2 increases the 0D exciton lifetimes to up to 14 ns and the cavity-enhanced quantum yields from an initial value of 1% to up to 65% (average 44%).

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Fig. 1: Overview of sample design enabling deterministic coupling of strain-induced excitons to nanoplasmonic gap modes.
Fig. 2: Optical characterization of strain-induced quantum emitters created by the nanocube array.
Fig. 3: Quantifying Purcell enhancement of plasmonically coupled quantum emitters.
Fig. 4: Exciton emission lifetime and quantum yield comparing CVT-grown with flux-grown WSe2.

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.


  1. 1.

    Senellart, P., Solomon, G. & White, A. High-performance semiconductor quantum-dot single-photon sources. Nat. Nanotech. 12, 1026–1039 (2017).

    CAS  Article  Google Scholar 

  2. 2.

    Aharonovich, I., Englund, D. & Toth, M. Solid-state single-photon emitters. Nat. Photon. 10, 631–641 (2016).

    CAS  Article  Google Scholar 

  3. 3.

    He, Y.-M. et al. Single quantum emitters in monolayer semiconductors. Nat. Nanotech. 10, 497–502 (2015).

    CAS  Article  Google Scholar 

  4. 4.

    Chakraborty, C., Kinnischtzke, L., Goodfellow, K. M., Beams, R. & Vamivakas, A. N. Voltage-controlled quantum light from an atomically thin semiconductor. Nat. Nanotech. 10, 507–511 (2015).

    CAS  Article  Google Scholar 

  5. 5.

    Koperski, M. et al. Single photon emitters in exfoliated WSe2 structures. Nat. Nanotech. 10, 503–506 (2015).

    CAS  Article  Google Scholar 

  6. 6.

    Srivastava, A. et al. Optically active quantum dots in monolayer WSe2. Nat. Nanotech. 10, 491–496 (2015).

    CAS  Article  Google Scholar 

  7. 7.

    Shepard, G. D. et al. Nanobubble induced formation of quantum emitters in monolayer semiconductors. 2D Mater. 4, 021019 (2017).

    Article  Google Scholar 

  8. 8.

    Palacios-Berraquero, C. et al. Large-scale quantum-emitter arrays in atomically thin semiconductors. Nat. Commun. 8, 15093 (2017).

    CAS  Article  Google Scholar 

  9. 9.

    Branny, A., Kumar, S., Proux, R. & Gerardot, B. D. Deterministic strain-induced arrays of quantum emitters in a two-dimensional semiconductor. Nat. Commun. 8, 15053 (2017).

    CAS  Article  Google Scholar 

  10. 10.

    Strauf, S. & Jahnke, F. Single quantum dot nanolaser. Laser Photon. Rev. 5, 607–633 (2011).

    Google Scholar 

  11. 11.

    Sapienza, L., Davanço, M., Badolato, A. & Srinivasan, K. Nanoscale optical positioning of single quantum dots for bright and pure single-photon emission. Nat. Commun. 6, 7833 (2015).

    CAS  Article  Google Scholar 

  12. 12.

    Schnauber, P. et al. Deterministic integration of quantum dots into on-chip multimode interference beamsplitters using in situ electron beam lithography. Nano Lett. 18, 2336–2342 (2018).

    CAS  Article  Google Scholar 

  13. 13.

    Riedel, D. et al. Deterministic enhancement of coherent photon generation from a nitrogen-vacancy center in ultrapure diamond. Phys. Rev. X 7, 031040 (2017).

    Google Scholar 

  14. 14.

    Zhang, J. L. et al. Strongly cavity-enhanced spontaneous emission from silicon-vacancy centers in diamond. Nano Lett. 18, 1360–1365 (2018).

    CAS  Article  Google Scholar 

  15. 15.

    Schneider, C. et al. Single photon emission from a site-controlled quantum dot–micropillar cavity system. Appl. Phys. Lett. 94, 111111 (2009).

    Article  Google Scholar 

  16. 16.

    Kaganskiy, A. et al. Micropillars with a controlled number of site-controlled quantum dots. Appl. Phys. Lett. 112, 071101 (2018).

    Article  Google Scholar 

  17. 17.

    Akselrod, G. M. et al. Probing the mechanisms of large Purcell enhancement in plasmonic nanoantennas. Nat. Photon. 8, 835–840 (2014).

    CAS  Article  Google Scholar 

  18. 18.

    Russell, K. J., Liu, T.-L., Cui, S. & Hu, E. L. Large spontaneous emission enhancement in plasmonic nanocavities. Nat. Photon. 6, 459–462 (2012).

    CAS  Article  Google Scholar 

  19. 19.

    Kongsuwan, N. et al. Suppressed quenching and strong-coupling of Purcell-enhanced single-molecule emission in plasmonic nanocavities. ACS Photon. 5, 186–191 (2017).

    Article  Google Scholar 

  20. 20.

    Luo, Y. et al. Purcell-enhanced quantum yield from carbon nanotube excitons coupled to plasmonic nanocavities. Nat. Commun. 8, 1413 (2017).

    Article  Google Scholar 

  21. 21.

    He, X. et al. Carbon nanotubes as emerging quantum-light sources. Nat. Mater. 17, 663–670 (2018).

    CAS  Article  Google Scholar 

  22. 22.

    Akselrod, G. M. et al. Leveraging nanocavity harmonics for control of optical processes in 2D semiconductors. Nano. Lett. 15, 3578–3584 (2015).

    CAS  Article  Google Scholar 

  23. 23.

    Hoang, T. B., Akselrod, G. M. & Mikkelsen, M. H. Ultrafast room-temperature single photon emission from quantum dots coupled to plasmonic nanocavities. Nano. Lett. 16, 270–275 (2015).

    Article  Google Scholar 

  24. 24.

    Tripathi, L. N. et al. Spontaneous emission enhancement in strain-induced WSe2 monolayer-based quantum light sources on metallic surfaces. ACS Photonics 5, 1919–1926 (2018).

    CAS  Article  Google Scholar 

  25. 25.

    Chikkaraddy, R. et al. Mapping nanoscale hotspots with single-molecule emitters assembled into plasmonic nanocavities using DNA origami. Nano. Lett. 18, 405–411 (2017).

    Article  Google Scholar 

  26. 26.

    Tran, T. T. et al. Deterministic coupling of quantum emitters in 2D materials to plasmonic nanocavity arrays. Nano. Lett. 17, 2634–2639 (2017).

    CAS  Article  Google Scholar 

  27. 27.

    Müller, M., Bounouar, S., Jöns, K. D., Glässl, M. & Michler, P. On-demand generation of indistinguishable polarization-entangled photon pairs. Nat. Photon. 8, 224–228 (2014).

    Article  Google Scholar 

  28. 28.

    Zhang, X.-X. et al. Magnetic brightening and control of dark excitons in monolayer WSe2. Nat. Nanotech. 12, 883–888 (2017).

    CAS  Article  Google Scholar 

  29. 29.

    Edelberg, D. et al. Hundredfold enhancement of light emission via defect control in monolayer transition-metal dichalcogenides. Preprint at (2018).

  30. 30.

    Ajayi, O. A. et al. Approaching the intrinsic photoluminescence linewidth in transition metal dichalcogenide monolayers. 2D Mater. 4, 031011 (2017).

    Article  Google Scholar 

  31. 31.

    Ross, J. S. et al. Electrically tunable excitonic light-emitting diodes based on monolayer WSe2 p–n junctions. Nat. Nanotech. 9, 268–272 (2014).

    CAS  Article  Google Scholar 

  32. 32.

    Baugher, B. W. H., Churchill, H. O. H., Yang, Y. & Jarillo-Herrero, P. Optoelectronic devices based on electrically tunable p–n diodes in a monolayer dichalcogenide. Nat. Nanotech. 9, 262–267 (2014).

    CAS  Article  Google Scholar 

  33. 33.

    Pospischil, A., Furchi, M. M. & Mueller, T. Solar-energy conversion and light emission in an atomic monolayer p–n diode. Nat. Nanotech. 9, 257–261 (2014).

    CAS  Article  Google Scholar 

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The authors thank M. Begliarbekov for supporting the development of the electron-beam lithography process at the City University of New York Advanced Science Research Center (ASRC) nanofabrication facility, and L. Dai for help with designing Fig. 1a. The authors acknowledge financial support to S.S. from the National Science Foundation (NSF) under awards DMR-1506711 and DMR-1809235 and to J.C.H. under awards DMR-1507423 and DMR-1809361. S.S. acknowledges financial support for the attoDRY1100 under NSF award ECCS-MRI-1531237.

Author information




S.S. and Y.L. designed the experiment. Y.L fabricated the plasmonic chips. G.D.S. and J.V.A. performed the layer transfer procedures. Y.L. and G.D.S. performed the optical experiments and analysed the data. D.A.R. and B.K. carried out the flux growth. K.B. and J.C.H. supervised the growth. S.S., G.D.S. and Y.L. co-wrote the paper. All authors discussed the results and commented on the manuscript.

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Correspondence to Stefan Strauf.

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Luo, Y., Shepard, G.D., Ardelean, J.V. et al. Deterministic coupling of site-controlled quantum emitters in monolayer WSe2 to plasmonic nanocavities. Nature Nanotech 13, 1137–1142 (2018).

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