Skip to main content

Thank you for visiting nature.com. 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.

Josephson coupled Ising pairing induced in suspended MoS2 bilayers by double-side ionic gating

A Publisher Correction to this article was published on 16 December 2019

This article has been updated

Abstract

Superconductivity in monolayer transition metal dichalcogenides is characterized by Ising-type pairing induced via a strong Zeeman-type spin–orbit coupling. When two transition metal dichalcogenides layers are coupled, more exotic superconducting phases emerge, which depend on the ratio of Ising-type protection and interlayer coupling strength. Here, we induce superconductivity in suspended MoS2 bilayers and unveil a coupled superconducting state with strong Ising-type spin–orbit coupling. Gating the bilayer symmetrically from both sides by ionic liquid gating varies the interlayer interaction and accesses electronic states with broken local inversion symmetry while maintaining the global inversion symmetry. We observe a strong suppression of the Ising protection that evidences a coupled superconducting state. The symmetric gating scheme not only induces superconductivity in both atomic sheets but also controls the Josephson coupling between the layers, which gives rise to a dimensional crossover in the bilayer.

This is a preview of subscription content

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Fig. 1: Crystal and device structure of suspended MoS2 bilayer.
Fig. 2: Superconducting phase diagram.
Fig. 3: Upper critical field measurements for single- and double-side gating on a bilayer MoS2.
Fig. 4: The IV mapping of the double-side gated bilayer MoS2.
Fig. 5: The interplay between SOC and interlayer interaction in superconductors with large in-plane Bc2.

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.

Change history

  • 16 December 2019

    An amendment to this paper has been published and can be accessed via a link at the top of the paper.

References

  1. 1.

    Lu, J. M. et al. Evidence for two-dimensional Ising superconductivity in gated MoS2. Science 350, 1353–1357 (2015).

    CAS  Article  Google Scholar 

  2. 2.

    Xi, X. et al. Ising pairing in superconducting NbSe2 atomic layers. Nat. Phys. 12, 139–143 (2015).

    Article  Google Scholar 

  3. 3.

    Saito, Y. et al. Superconductivity protected by spin–valley locking in ion-gated MoS2. Nat. Phys. 12, 144–149 (2015).

    Article  Google Scholar 

  4. 4.

    Lu, J. et al. Full superconducting dome of strong Ising protection in gated monolayer WS2. Proc. Natl Acad. Sci. USA 115, 3551–3556 (2018).

    CAS  Article  Google Scholar 

  5. 5.

    de la Barrera, S. C. et al. Tuning Ising superconductivity with layer and spin–orbit coupling in two-dimensional transition-metal dichalcogenides. Nat. Commun. 9, 1427 (2018).

    Article  Google Scholar 

  6. 6.

    Nakosai, S., Tanaka, Y. & Nagaosa, N. Topological superconductivity in bilayer Rashba system. Phys. Rev. Lett. 108, 147003 (2012).

    Article  Google Scholar 

  7. 7.

    Liu, C.-X. Unconventional superconductivity in bilayer transition metal dichalcogenides. Phys. Rev. Lett. 118, 087001 (2017).

    Article  Google Scholar 

  8. 8.

    Nakamura, Y. & Yanase, Y. Odd-parity superconductivity in bilayer transition metal dichalcogenides. Phys. Rev. B. 96, 054501 (2017).

    Article  Google Scholar 

  9. 9.

    Mizukami, Y. et al. Extremely strong-coupling superconductivity in artificial two-dimensional Kondo lattices. Nat. Phys. 7, 849–853 (2011).

    CAS  Article  Google Scholar 

  10. 10.

    Liu, Y. et al. Interface-induced zeeman-protected superconductivity in ultrathin crystalline lead films. Phys. Rev. X 8, 021002 (2018).

    CAS  Google Scholar 

  11. 11.

    Zhang, X., Liu, Q., Luo, J.-W., Freeman, A. J. & Zunger, A. Hidden spin polarization in inversion-symmetric bulk crystals. Nat. Phys. 10, 387–393 (2014).

    CAS  Article  Google Scholar 

  12. 12.

    Tombros, N. et al. Large yield production of high mobility freely suspended graphene electronic devices on a polydimethylglutarimide based organic polymer. J. Appl. Phys. 109, 093702 (2011).

    Article  Google Scholar 

  13. 13.

    Wang, F. et al. Ionic liquid gating of suspended MoS2 field-effect transistor devices. Nano Lett. 15, 5284–5288 (2015).

    CAS  Article  Google Scholar 

  14. 14.

    Ye, J. T. et al. Superconducting dome in a gate-tuned band insulator. Science 338, 1193–1196 (2012).

    CAS  Article  Google Scholar 

  15. 15.

    Eknapakul, T. et al. Electronic structure of a Quasi-freestanding MoS2 monolayer. Nano Lett. 14, 1312–1316 (2014).

    CAS  Article  Google Scholar 

  16. 16.

    Kim, B. S., Rhim, J.-W., Kim, B., Kim, C. & Park, S. R. Determination of the band parameters of bulk 2H-MX2 (M = Mo, W; X = S, Se) by angle-resolved photoemission spectroscopy. Sci. Rep. 6, 36389 (2016).

    CAS  Article  Google Scholar 

  17. 17.

    Brumme, T., Calandra, M. & Mauri, F. First-principles theory of field-effect doping in transition-metal dichalcogenides: Structural properties, electronic structure, Hall coefficient, and electrical conductivity. Phys. Rev. B. 91, 155436 (2015).

    Article  Google Scholar 

  18. 18.

    Ovchinnikov, D. et al. Disorder engineering and conductivity dome in ReS2 with electrolyte gating. Nat. Commun. 7, 12391 (2016).

    CAS  Article  Google Scholar 

  19. 19.

    Coleman, R. V., Eiserman, G. K., Hillenius, S. J., Mitchell, A. T. & Vicent, J. L. Dimensional crossover in the superconducting intercalated layer compound 2H-TaS2. Phys. Rev. B. 27, 125–139 (1983).

    CAS  Article  Google Scholar 

  20. 20.

    Yang, Y. et al. Enhanced superconductivity upon weakening of charge density wave transport in 2H-TaS2 in the two-dimensional limit. Phys. Rev. B. 98, 035203 (2018).

    CAS  Article  Google Scholar 

  21. 21.

    Klemm, R. A., Luther, A. & Beasley, M. R. Theory of the upper critical field in layered superconductors. Phys. Rev. B. 12, 877–891 (1975).

    Article  Google Scholar 

  22. 22.

    Klemm, R. A. Layered Superconductors Volume 1 International Series of Monographs on Physics, Vol. 153 (Oxford Univ. Press, 2011).

  23. 23.

    Xia, Y., Xie, W., Ruden, P. P. & Frisbie, C. D. Carrier localization on surfaces of organic semiconductors gated with electrolytes. Phys. Rev. Lett. 105, 036802 (2010).

    Article  Google Scholar 

  24. 24.

    Talantsev, E. F. et al. On the origin of critical temperature enhancement in atomically thin superconductors. 2D Mater. 4, 025072 (2017).

    Article  Google Scholar 

  25. 25.

    Inosov, D. S. et al. Crossover from weak to strong pairing in unconventional superconductors. Phys. Rev. B. 83, 214520 (2011).

    Article  Google Scholar 

  26. 26.

    Devarakonda, A. et al. Evidence for clean 2D superconductivity and field-induced finite-momentum pairing in a bulk vdW superlattice. Preprint at https://arxiv.org/abs/1906.02065 (2019).

  27. 27.

    Ma, Y. et al. Unusual evolution of B c2 and T c with inclined fields in restacked TaS2 nanosheets. NPJ Quantum Mater. 3, 34 (2018).

    Article  Google Scholar 

  28. 28.

    Goh, S. K. et al. Anomalous upper critical field in CeCoIn5/YbCoIn5 superlattices with a Rashba-type heavy Fermion interface. Phys. Rev. Lett. 109, 157006 (2012).

    CAS  Article  Google Scholar 

  29. 29.

    Sekihara, T., Masutomi, R. & Okamoto, T. Two-dimensional superconducting state of monolayer Pb films grown on GaAs(110) in a strong parallel magnetic field. Phys. Rev. Lett. 111, 057005 (2013).

    Article  Google Scholar 

  30. 30.

    Woollam, J. A. & Somoano, R. B. Superconducting critical fields of alkali and alkaline-earth intercalates of MoS2. Phys. Rev. B. 13, 3843–3853 (1976).

    CAS  Article  Google Scholar 

Download references

Acknowledgements

J.T.Y. acknowledges funding from the European Research Council (consolidator grant no. 648855, Ig-QPD). We acknowledge D.-H. Xu for a fruitful discussion on the KLB model.

Author information

Affiliations

Authors

Contributions

O.Z., J.M.L. and J.T.Y. designed the experiment. O.Z. and J.M.L. fabricated the device and performed the measurements. O.Z., J.M.L., Q.H.C., A.A.E.Y., S.G. and J.T.Y analysed and discussed the data. O.Z. and J.T.Y. wrote the manuscript.

Corresponding author

Correspondence to J. T. Ye.

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

Supplementary Figs. 1–6, Tables 1–4 and refs. 1–11.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Zheliuk, O., Lu, J.M., Chen, Q.H. et al. Josephson coupled Ising pairing induced in suspended MoS2 bilayers by double-side ionic gating. Nat. Nanotechnol. 14, 1123–1128 (2019). https://doi.org/10.1038/s41565-019-0564-1

Download citation

Further reading

Search

Quick links

Find nanotechnology articles, nanomaterial data and patents all in one place. Visit Nano by Nature Research