Picosecond photoresponse in van der Waals heterostructures

Abstract

Two-dimensional crystals such as graphene and transition-metal dichalcogenides1 demonstrate a range of unique and complementary optoelectronic properties2,3. Assembling different two-dimensional materials in vertical heterostructures4 enables the combination of these properties in one device, thus creating multifunctional optoelectronic systems with superior performance. Here, we demonstrate that graphene/WSe2/graphene heterostructures ally the high photodetection efficiency of transition-metal dichalcogenides5,6 with a picosecond photoresponse comparable to that of graphene7,8,9, thereby optimizing both speed and efficiency in a single photodetector. We follow the extraction of photoexcited carriers in these devices using time-resolved photocurrent measurements and demonstrate a photoresponse time as short as 5.5 ps, which we tune by applying a bias and by varying the transition-metal dichalcogenide layer thickness. Our study provides direct insight into the physical processes governing the detection speed and quantum efficiency of these van der Waals heterostuctures, such as out-of-plane carrier drift and recombination. The observation and understanding of ultrafast and efficient photodetection demonstrate the potential of hybrid transition-metal dichalcogenide-based heterostructures as a platform for future optoelectronic devices.

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Figure 1: Photocurrent generation in the G/WSe2/G heterostructure.
Figure 2: Extraction of the photoresponse time of a G/2.2 nm WSe2/G heterostructure by time-resolved photocurrent measurements.
Figure 3: Tuning of photoresponse time τ by variation of the WSe2 layer thickness L and bias voltage VB.
Figure 4: Dynamic processes governing the photoresponse of G/WSe2/G heterostructures.

References

  1. 1

    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).

    Article  Google Scholar 

  2. 2

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

    CAS  Article  Google Scholar 

  3. 3

    Bonaccorso, F., Sun, Z., Hasan, T. & Ferrari, A. C. Graphene photonics and optoelectronics. Nature Photon. 4, 611–622 (2010).

    CAS  Article  Google Scholar 

  4. 4

    Geim, A. K. & Grigorieva, I. V. Van der Waals heterostructures. Nature 499, 419–425 (2013).

    CAS  Article  Google Scholar 

  5. 5

    Britnell, L. et al. Strong light–matter interactions in heterostructures of atomically thin films. Science 340, 1311–1314 (2013).

    CAS  Article  Google Scholar 

  6. 6

    Yu, W. J. et al. Highly efficient gate-tunable photocurrent generation in vertical heterostructures of layered materials. Nature Nanotech. 8, 952–958 (2013).

    CAS  Article  Google Scholar 

  7. 7

    Urich, A., Unterrainer, K. & Mueller, T. Intrinsic response time of graphene photodetectors. Nano Lett. 11, 2804–2808 (2011).

    CAS  Article  Google Scholar 

  8. 8

    Koppens, F. H. L. et al. Photodetectors based on graphene, other two-dimensional materials and hybrid systems. Nature Nanotech. 9, 780–793 (2014).

    CAS  Article  Google Scholar 

  9. 9

    Schall, D. et al. 50 GBit/s photodetectors based on wafer-scale graphene for integrated silicon photonic communication systems. ACS Photon. 1, 781–784 (2014).

    CAS  Article  Google Scholar 

  10. 10

    Eda, G. & Maier, S. A. Two-dimensional crystals: managing light for optoelectronics. ACS Nano 7, 5660–5665 (2013).

    CAS  Article  Google Scholar 

  11. 11

    Furchi, M. M., Polyushkin, D. K., Pospischil, A. & Mueller, T. Mechanisms of photoconductivity in atomically thin MoS2 . Nano Lett. 14, 6165–6170 (2014).

    CAS  Article  Google Scholar 

  12. 12

    Klots, A. R. et al. Probing excitonic states in suspended two-dimensional semiconductors by photocurrent spectroscopy. Sci. Rep. 4, 6608 (2014).

    CAS  Article  Google Scholar 

  13. 13

    Lee, C.-H. et al. Atomically thin p–n junctions with van der Waals heterointerfaces. Nature Nanotech. 9, 676–681 (2014).

    CAS  Article  Google Scholar 

  14. 14

    Lopez-Sanchez, O., Lembke, D., Kayci, M., Radenovic, A. & Kis, A. Ultrasensitive photodetectors based on monolayer MoS2 . Nature Nanotech. 8, 497–501 (2013).

    CAS  Article  Google Scholar 

  15. 15

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

    CAS  Article  Google Scholar 

  16. 16

    Youngblood, N., Chen, C., Koester, S. J. & Li, M. Waveguide-integrated black phosphorus photodetector with high responsivity and low dark current. Nature Photon. 9, 1–6 (2015).

    Article  Google Scholar 

  17. 17

    Ferrari, A. C. et al. Science and technology roadmap for graphene, related two-dimensional crystals, and hybrid systems. Nanoscale 7, 4598–4810 (2015).

    CAS  Article  Google Scholar 

  18. 18

    Carvalho, A., Ribeiro, R. M. & Castro Neto, a. H. Band nesting and the optical response of two-dimensional semiconducting transition metal dichalcogenides. Phys. Rev. B 88, 115205 (2013).

    Article  Google Scholar 

  19. 19

    Cui, Q., Ceballos, F., Kumar, N. & Zhao, H. Transient absorption microscopy of monolayer and bulk WSe2 . ACS Nano 8, 2970–2976 (2014).

    CAS  Article  Google Scholar 

  20. 20

    He, J. et al. Electron transfer and coupling in graphene–tungsten disulfide van der Waals heterostructures. Nature Commun. 5, 5622 (2014).

    CAS  Article  Google Scholar 

  21. 21

    Mouri, S. et al. Nonlinear photoluminescence in atomically thin layered WSe2 arising from diffusion-assisted exciton–exciton annihilation. Phys. Rev. B 90, 155449 (2014).

    Article  Google Scholar 

  22. 22

    Nie, Z. et al. Ultrafast carrier thermalization and cooling dynamics in few-layer MoS2 . ACS Nano 8, 10931–10940 (2014).

    CAS  Article  Google Scholar 

  23. 23

    Shi, H. et al. Exciton dynamics in suspended monolayer and few-layer MoS2 2D crystals. ACS Nano 7, 1072–1080 (2013).

    CAS  Article  Google Scholar 

  24. 24

    Strait, J. H., Nene, P. & Rana, F. High intrinsic mobility and ultrafast carrier dynamics in multilayer metal-dichalcogenide MoS2 . Phys. Rev. B 90, 245402 (2014).

    Article  Google Scholar 

  25. 25

    Sun, D. et al. Observation of rapid exciton–exciton annihilation in monolayer molybdenum disulfide. Nano Lett. 14, 5625–5629 (2014).

    CAS  Article  Google Scholar 

  26. 26

    Wang, H., Zhang, C. & Rana, F. Ultrafast dynamics of defect-assisted electron–hole recombination in monolayer MoS2 . Nano Lett. 15, 339–345 (2014).

    Article  Google Scholar 

  27. 27

    Borzda, T. et al. Charge photogeneration in few-layer MoS2 . Adv. Funct. Mater. 25, 3351–3358 (2015).

    CAS  Article  Google Scholar 

  28. 28

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

    CAS  Article  Google Scholar 

  29. 29

    Gabor, N. M., Zhong, Z., Bosnick, K. & McEuen, P. L. Ultrafast photocurrent measurement of the escape time of electrons and holes from carbon nanotube p–i–n photodiodes. Phys. Rev. Lett. 108, 087404 (2012).

    Article  Google Scholar 

  30. 30

    Zhao, W. et al. Evolution of electronic structure in atomically thin sheets of WS2 and WSe2 . ACS Nano 7, 791–797 (2013).

    CAS  Article  Google Scholar 

  31. 31

    Wilson, J. A. & Yoffe, A. D. The transition metal dichalcogenides discussion and interpretation of the observed optical, electrical and structural properties. Adv. Phys. 18, 193–335 (1969).

    CAS  Article  Google Scholar 

  32. 32

    Beal, A. R., Knights, J. C. & Liang, W. Y. Transmission spectra of some transition metal dichalcogenides. II. Group VIA: trigonal prismatic coordination. J. Phys. C 5, 3540–3551 (1972).

    CAS  Article  Google Scholar 

  33. 33

    Wang, K. et al. Ultrafast saturable absorption of two-dimensional MoS2 nanosheets. ACS Nano 7, 9260–9267 (2013).

    CAS  Article  Google Scholar 

  34. 34

    Li, D. et al. Electric-field-induced strong enhancement of electroluminescence in multilayer molybdenum disulfide. Nature Commun. 6, 7509 (2015).

    Article  Google Scholar 

  35. 35

    Kautek, W. Electronic mobility anisotropy of layered semiconductors: transversal photoconductivity measurements at n-MoSe2 . J. Phys. C 15, L519–L525 (1982).

    CAS  Article  Google Scholar 

  36. 36

    Swathi, R. S. & Sebastian, K. L. Resonance energy transfer from a dye molecule to graphene. J. Chem. Phys. 129, 054703 (2008).

    CAS  Article  Google Scholar 

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Acknowledgements

The authors thank Q. Ma and P. Jarillo-Herrero for their instruction on the layer assembly technique, and M. Lundeberg for discussions. M.M. acknowledges support from the Natural Sciences and Engineering Research Council of Canada (PGSD3-426325-2012). F.V. acknowledges financial support from Marie-Curie International Fellowship COFUND and the ICFOnest programme. F.K. acknowledges support by Fundacio Cellex Barcelona, the ERC Career integration grant (294056, GRANOP), the ERC starting grant (307806, CarbonLight), the Mineco grants RYC-2012-12281 and FIS2013-47161-P, and support by the EC under the Graphene Flagship (contract no. CNECT-ICT-604391). P.S. acknowledges financial support from a scholarship from the ‘la Caixa’ Banking Foundation.

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M.M. and F.H.L.K. conceived and designed the experiments. M.M., P.S. and F.V. fabricated the samples, carried out the experiments and performed the data analysis. K.W. and T.T. provided boron nitride crystals. K.G.S. and A.R.P. provided assistance for the photoluminescence measurements. M.M., F.V., K.J.T., P.S. and F.H.L.K co-wrote the manuscript, with the participation of K.G.S. and A.R.P.

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Correspondence to F. H. L. Koppens.

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Massicotte, M., Schmidt, P., Vialla, F. et al. Picosecond photoresponse in van der Waals heterostructures. Nature Nanotech 11, 42–46 (2016). https://doi.org/10.1038/nnano.2015.227

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