Electrical control of charged carriers and excitons in atomically thin materials

  • Nature Nanotechnologyvolume 13pages128132 (2018)
  • doi:10.1038/s41565-017-0030-x
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Electrical confinement and manipulation of charge carriers in semiconducting nanostructures are essential for realizing functional quantum electronic devices1,2,3. The unique band structure4,5,6,7 of atomically thin transition metal dichalcogenides (TMDs) offers a new route towards realizing novel 2D quantum electronic devices, such as valleytronic devices and valley–spin qubits8. 2D TMDs also provide a platform for novel quantum optoelectronic devices9,10,11 due to their large exciton binding energy12,13. However, controlled confinement and manipulation of electronic and excitonic excitations in TMD nanostructures have been technically challenging due to the prevailing disorder in the material, preventing accurate experimental control of local confinement and tunnel couplings14,15,16. Here we demonstrate a novel method for creating high-quality heterostructures composed of atomically thin materials that allows for efficient electrical control of excitations. Specifically, we demonstrate quantum transport in the gate-defined, quantum-confined region, observing spin–valley locked quantized conductance in quantum point contacts. We also realize gate-controlled Coulomb blockade associated with confinement of electrons and demonstrate electrical control over charged excitons with tunable local confinement potentials and tunnel couplings. Our work provides a basis for novel quantum opto-electronic devices based on manipulation of charged carriers and excitons.

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  1. 1.

    Loss, D. & DiVincenzo, D. P. Quantum computation with quantum dots. Phys. Rev. A 57, 120 (1998).

  2. 2.

    Petta, J. R. et al. Coherent manipulation of coupled electron spins in semiconductor quantum dots. Science 309, 2180–2184 (2005).

  3. 3.

    Hanson, R., Kouwenhoven, L. P., Petta, J. R., Tarucha, S. & Vandersypen, L. M. K. Spin in few-electron quantum dots. Rev. Mod. Phys. 79, 1217 (2007).

  4. 4.

    Jariwala, D., Sangwan, V. K., Lauhon, L. J., Marks, T. J. & Hersam, M. C. Emerging device applications for semiconducting two-dimensional transition metal dichalcogenides. ACS Nano 8, 1102–1120 (2014).

  5. 5.

    Jariwala, D., Marks, T. J. & Hersam, M. C. Mixed-dimensional van der Waals heterostructures. Nat. Mater. 16, 170–181 (2017).

  6. 6.

    Xiao, D., Liu, G., Feng, W., Xu, X. & Yao, W. Coupled spin and valley physics in monolayers of MoS2 and other group-VI dichalcogenides. Phys. Rev. Lett. 108, 196802 (2012).

  7. 7.

    Xu, X., Yao, W., Xiao, D. & Heinz, T. F. Spin and pseudospins in layered transition metal dichalcogenides. Nat. Phys. 10, 343–350 (2014).

  8. 8.

    Kormányos, A., Zólyomi, V., Drummond, N. D. & Burkard, G. Spin-orbit coupling, quantum dots, and qubits in monolayer transition metal dichalcogenides. Phys. Rev. X 4, 011034 (2014).

  9. 9.

    Rivera, P. et al. Valley-polarized exciton dynamics in a 2D semiconductor heterostructure. Science 351, 6274 (2016).

  10. 10.

    Wang, Q. H., Kalantar-Zadeh, K., Kis, A., Coleman, J. N. & Strano, M. S. Electronics and optoelectronics of two-dimensional transition metal dichalcogenides. Nat. Nanotech. 7, 699–712 (2012).

  11. 11.

    Ma, K. F. & Shan, J. Photonics and optoelectronics of 2D semiconductor transition metal dichalcogenides. Nat. Photon. 10, 216–226 (2016).

  12. 12.

    Moody, G. et al. Electronic enhancement of the exciton coherence time in charged quantum dots. Phys. Rev. Lett. 116, 037402 (2016).

  13. 13.

    Pioda, A. et al. Single-shot detection of electrons generated by individual photons in a tunable lateral quantum dot. Phys. Rev. Lett. 106, 146804 (2011).

  14. 14.

    Lee, K., Kulkarnia, G. & Zhong, Z. Coulomb blockade in monolayer MoS2 single electron transistor. Nanoscale 8, 7755–7760 (2016).

  15. 15.

    Song, X.-X. et al. A gate defined quantum dot on the two-dimensional transition metal dichalcogenide semiconductor WSe2. Nanoscale 7, 16867–16873 (2015).

  16. 16.

    Song, X.-X. et al. Temperature dependence of Coulomb oscillations in a few-layer two-dimensional WS2 quantum dot. Sci. Rep. 5, 16113 (2015).

  17. 17.

    Mak, K. F., Lee, C., Hone, J., Shan, J. & Heinz, T. F. Atomically thin MoS2: a new direct-gap semiconductor. Phys. Rev. Lett. 105, 136805 (2010).

  18. 18.

    Radisavljevic, B., Radenovic, A., Brivio, J., Giacometti, V. & Kis, A. Single-layer MoS2 transistors. Nat. Nanotech. 6, 147–150 (2011).

  19. 19.

    Wu, Z. et al. Even–odd layer-dependent magnetotransport of high-mobility Q-valley electrons in transition metal disulfides. Nat. Commun. 7, 12955 (2016).

  20. 20.

    Laroche, D., Gervais, G., Lilly, M. P. & Reno, J. L. 1D–1D Coulomb drag signature of a Luttinger liquid. Science 343, 6171 (2014).

  21. 21.

    Bischoff, D. et al. Measurement back-action in stacked graphene quantum dots. Nano Lett. 15, 6003–6008 (2015).

  22. 22.

    Payette, C. et al. Single charge sensing and transport in double quantum dots fabricated from commercially grown Si/SiGe heterostructures. Appl. Phys. Lett. 100, 043508 (2012).

  23. 23.

    Wang, M. et al. Quantum dot behavior in bilayer graphene nanoribbons. ACS Nano 5, 8769–8773 (2011).

  24. 24.

    Cui, X. et al. Multi-terminal transport measurements of MoS2 using a van der Waals heterostructure device platform. Nat. Nanotech. 10, 534–540 (2015).

  25. 25.

    Kim, K. et al. Shubnikov–de Haas oscillations of high-mobility holes in monolayer and bilayer WSe2: Landau level degeneracy, effective mass, and negative compressibility. Phys. Rev. Lett. 116, 086601 (2016).

  26. 26.

    Kayyalha, M., Maassen, J., Lundstrom, M., Shi, L. & Chen, Y. P. Gate-tunable and thickness-dependent electronic and thermoelectric transport in few-layer MoS2. J. Appl. Phys. 120, 134305 (2016).

  27. 27.

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

  28. 28.

    van Wees, B. J. et al. Quantized conductance of point contacts in a two-dimensional electron gas. Phys. Rev. Lett. 60, 848 (1988).

  29. 29.

    Wang, K., Payette, C., Dovzhenko, Y., Deelman, P. W. & Petta, J. R. Charge relaxation in a single-electron Si/SiGe double quantum dot. Phys. Rev. Lett. 111, 046801 (2013).

  30. 30.

    Sidler, M. et al. Fermi polaron–polaritons in charge tunable atomically thin semiconductors. Nat. Phys. 13, 255–261 (2016).

  31. 31.

    Scharf, B. et al. Probing many-body interactions in monolayer transition metal dichalcogenides. Preprint at https://arxiv.org/abs/1606.07101 (2016).

  32. 32.

    Efemkin, D. K. & MacDonald, A. H. Many-body theory of trion absorption features in two-dimensional semiconductors. Phys. Rev. B 95, 035417 (2017).

  33. 33.

    Umansky, V., de-Picciotto, R. & Heiblum, M. Extremely high-mobility two dimensional electron gas: evaluation of scattering mechanisms. Appl. Phys. Lett. 71, 683 (1997).

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We thank J. Waissman and E. Lee for helpful discussions. The major experimental work was supported by AFOSR (grant FA9550-14-1-0268), DoD Vannevar Bush Faculty Fellowship (grant N00014-16-1-2825), and Samsung Electronics. K.W. acknowledges support from ARO MURI (W911NF-14-1-0247). P.K. acknowledges partial support from ONR MURI (grant N00014-15-1-2761) and the FAME Center. H.P. and M.D.L. acknowledge partial support from AFOSR MURI (FA9550-17-1-0002), NSF (PHY-1506284), and NSF CUA (PHY-1125846). K.W. and T.T. acknowledge support from the Elemental Strategy Initiative conducted by the MEXT, Japan and JSPS KAKENHI grant numbers JP26248061, JP15K21722 and JP25106006. A portion of this work was performed at the National High Magnetic Field Laboratory, which is supported by National Science Foundation Cooperative Agreement No. DMR-1157490 and the State of Florida. Nanofabrication was performed at the Center for Nanoscale Systems at Harvard, supported in part by an NSF NNIN award ECS-00335765.

Author information


  1. Department of Physics, Harvard University, Cambridge, MA, USA

    • Ke Wang
    • , Kristiaan De Greve
    • , Luis A. Jauregui
    • , Andrey Sushko
    • , Alexander High
    • , You Zhou
    • , Giovanni Scuri
    • , Mikhail D. Lukin
    • , Hongkun Park
    •  & Philip Kim
  2. Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA

    • Kristiaan De Greve
    • , Alexander High
    • , You Zhou
    •  & Hongkun Park
  3. National Institute for Materials Science, Namiki 1-1, Ibaraki, Japan

    • Takashi Taniguchi
    •  & Kenji Watanabe


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K.W. performed the experiments and analysed the data. K.D.G., L.J., A.S., A.H., Y.Z. and G.S. performed optical measurements, K.W. and L.J. fabricated devices, K.W. and P.K. conceived the electron transport experiment. K.W., K.D.G., M.L., H.P. and P.K. conceived the optoelectronic experiment. K.W. and T.T. provided hBN crystals.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Philip Kim.

Supplementary information

  1. Supplementary Information

    Supplementary Figs. 1–3 and Supplementary References.