Skip to main content

Thank you for visiting 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.

Spectroscopic evidence for a type II Weyl semimetallic state in MoTe2


In a type I Dirac or Weyl semimetal, the low-energy states are squeezed to a single point in momentum space when the chemical potential μ is tuned precisely to the Dirac/Weyl point1,2,3,4,5,6. Recently, a type II Weyl semimetal was predicted to exist, where the Weyl states connect hole and electron bands, separated by an indirect gap7,8,9,10. This leads to unusual energy states, where hole and electron pockets touch at the Weyl point. Here we present the discovery of a type II topological Weyl semimetal state in pure MoTe2, where two sets of Weyl points (, ) exist at the touching points of electron and hole pockets and are located at different binding energies above EF. Using angle-resolved photoemission spectroscopy, modelling, density functional theory and calculations of Berry curvature, we identify the Weyl points and demonstrate that they are connected by different sets of Fermi arcs for each of the two surface terminations. We also find new surface ‘track states’ that form closed loops and are unique to type II Weyl semimetals. This material provides an exciting, new platform to study the properties of Weyl fermions.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1: A simple model of the type II Weyl semimetal described by a two-band model given by equation (2) that exhibits four Weyl nodes.
Figure 2: Experimental Fermi surface and band structure of MoTe2.
Figure 3: Identification of WPs and Fermi arcs from experimental data.
Figure 4: Results of DFT calculations.


  1. 1

    Weng, H., Fang, C., Fang, Z., Bernevig, B. A. & Dai, X. Weyl semimetal phase in noncentrosymmetric transition-metal monophosphides. Phys. Rev. X 5, 011029 (2015).

    Google Scholar 

  2. 2

    Xu, S.-Y. et al. Discovery of a Weyl fermion semimetal and topological Fermi arcs. Science 349, 613–617 (2015).

    CAS  Article  Google Scholar 

  3. 3

    Yang, L. X. et al. Weyl semimetal phase in the non-centrosymmetric compound TaAs. Nature Phys. 11, 728–733 (2015).

    CAS  Article  Google Scholar 

  4. 4

    Lv, B. Q. et al. Observation of Weyl nodes in TaAs. Nature Phys. 11, 724–728 (2015).

    Article  Google Scholar 

  5. 5

    Xu, S.-Y. et al. Discovery of a Weyl fermion state with Fermi arcs in niobium arsenide. Nature Phys. 11, 748–754 (2015).

    CAS  Article  Google Scholar 

  6. 6

    Liu, Z. K. et al. Evolution of the Fermi surface of Weyl semimetals in the transition metal pnictide family. Nature Mater. 15, 27–32 (2015).

    Article  Google Scholar 

  7. 7

    Sun, Y., Wu, S.-C., Ali, M. N., Felser, C. & Yan, B. Prediction of Weyl semimetal in orthorhombic MoTe2 . Phys. Rev. B 92, 161107 (2015).

    Article  Google Scholar 

  8. 8

    Soluyanov, A. A. et al. Type-II Weyl semimetals. Nature 527, 495–498 (2015).

    CAS  Article  Google Scholar 

  9. 9

    Lv, B. Q. et al. Experimental discovery of Weyl semimetal TaAs. Phys. Rev. X 5, 031013 (2015).

    Google Scholar 

  10. 10

    Huang, S.-M. et al. New type of Weyl semimetal with quadratic double Weyl fermions. Proc. Natl Acad. Sci. USA 113, 1180–1185 (2016).

    CAS  Article  Google Scholar 

  11. 11

    Weyl, H. Gravitation and the electron. Proc. Natl Acad. Sci. USA 15, 323–334 (1929).

    CAS  Article  Google Scholar 

  12. 12

    Hsieh, D. et al. A topological Dirac insulator in a quantum spin Hall phase. Nature 452, 970–974 (2008).

    CAS  Article  Google Scholar 

  13. 13

    Burkov, A. A. & Balents, L. Weyl semimetal in a topological insulator multilayer. Phys. Rev. Lett. 107, 127205 (2011).

    CAS  Article  Google Scholar 

  14. 14

    Liu, Z. K. et al. Discovery of a three-dimensional topological Dirac semimetal, Na3Bi. Science 343, 864–867 (2014).

    CAS  Article  Google Scholar 

  15. 15

    Wan, X., Turner, A. M., Vishwanath, A. & Savrasov, S. Y. Topological semimetal and Fermi-arc surface states in the electronic structure of pyrochlore iridates. Phys. Rev. B 83, 1–9 (2011).

    Google Scholar 

  16. 16

    Chen, Y. et al. Nanostructured carbon allotropes with Weyl-like loops and points. Nano Lett. 15, 6974–6978 (2015).

    CAS  Article  Google Scholar 

  17. 17

    Xu, Y., Zhang, F. & Zhang, C. Structured Weyl points in spin-orbit coupled fermionic superfluids. Phys. Rev. Lett. 115, 265304 (2015).

    Article  Google Scholar 

  18. 18

    Wang, Z. et al. MoTe2: Weyl and line node topological metal. Preprint at (2015).

  19. 19

    Burkov, A. A., Hook, M. D. & Balents, L. Topological nodal semimetals. Phys. Rev. B 84, 235126 (2011).

    Article  Google Scholar 

  20. 20

    Heikkil, T. & Volovik, G. Dimensional crossover in topological matter: evolution of the multiple Dirac point in the layered system to the flat band on the surface. JETP Lett. 93, 59–65 (2011).

    Article  Google Scholar 

  21. 21

    Wu, Y. et al. Dirac node arcs in PtSn4 . Nature Phys. 12, 667–671 (2016).

    CAS  Article  Google Scholar 

  22. 22

    Belopolski, I. et al. Unoccupied electronic structure and signatures of topological Fermi arcs in the Weyl semimetal candidate MoxW1−xTe2. Preprint at (2015).

  23. 23

    Canfield, P. C., Kong, T., Kaluarachchi, U. S. & Jo, N. H. Use of frit-disc crucibles for routine and exploratory solution growth of single crystalline samples. Phil. Mag. 96, 84–92 (2016).

    CAS  Article  Google Scholar 

  24. 24

    Jiang, R. et al. Tunable vacuum ultraviolet laser based spectrometer for angle resolved photoemission spectroscopy. Rev. Sci. Instrum. 85, 033902 (2014).

    Article  Google Scholar 

  25. 25

    Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 3865–3868 (1996).

    CAS  Article  Google Scholar 

  26. 26

    Blaha, P., Schwarz, K., Madsen, G. K. H., Kvasnicka, D. & Luitz, J. WIEN2K, An Augmented Plane Wave + Local Orbitals Program for Calculating Crystal Properties (Karlheinz Schwarz, Techn. Universität Wien, 2001).

    Google Scholar 

  27. 27

    Marzari, N. & Vanderbilt, D. Maximally localized generalized Wannier functions for composite energy bands. Phys. Rev. B 56, 12847–12865 (1997).

    CAS  Article  Google Scholar 

  28. 28

    Souza, I., Marzari, N. & Vanderbilt, D. Maximally localized Wannier functions for entangled energy bands. Phys. Rev. B 65, 035109 (2001).

    Article  Google Scholar 

  29. 29

    Mostofi, A. A. et al. Wannier90: a tool for obtaining maximally-localized Wannier functions. Comput. Phys. Commun. 178, 685–699 (2008).

    CAS  Article  Google Scholar 

  30. 30

    Wang, X., Yates, J. R., Souza, I. & Vanderbilt, D. Ab initio calculation of the anomalous Hall conductivity by Wannier interpolation. Phys. Rev. B 74, 195118 (2006).

    Article  Google Scholar 

Download references


The work at Ames Laboratory was supported by the US Department of Energy, Office of Science, Basic Energy Sciences, Materials Science and Engineering Division (ARPES measurements). Ames Laboratory is operated for the US Department of Energy by Iowa State University under contract No. DE-AC02-07CH11358. Data analysis, theory and modelling was supported by the Center for Emergent Materials, an NSF MRSEC, under grant DMR-1420451. T.M.M. acknowledges funding from NSF-DMR-1309461 and would like to thank the 2015 Princeton Summer School for Condensed Matter Physics for their hospitality. N.T. acknowledges partial support by a grant from the Simons Foundation (no. 343227). Work at ORNL (sample growth) was supported by the US Department of Energy, Office of Science, Basic Energy Sciences, Scientific User Facilities Division (H.C.), and Materials Science and Engineering Division (J.Y.).

Author information




N.T. and T.M.M. provided theoretical modelling and interpretation. J.Y. and Z.Z. grew the samples. M.O., M.-T.S. and R.A. performed DFT and Berry phase calculations. H.C. performed crystal structure determination. L.H., Y.W. and D.M. performed ARPES measurements and support. L.H. analysed ARPES data. The manuscript was drafted by L.H., T.M.M., N.T. and A.K. All authors discussed and commented on the manuscript.

Corresponding author

Correspondence to Adam Kaminski.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Huang, L., McCormick, T., Ochi, M. et al. Spectroscopic evidence for a type II Weyl semimetallic state in MoTe2. Nature Mater 15, 1155–1160 (2016).

Download citation

Further reading


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing