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Evidence for magnetic Weyl fermions in a correlated metal

Abstract

Weyl fermions1,2,3 have been observed as three-dimensional, gapless topological excitations in weakly correlated, inversion-symmetry-breaking semimetals4,5. However, their realization in spontaneously time-reversal-symmetry-breaking phases of strongly correlated materials has so far remained hypothetical2,6,7. Here, we report experimental evidence for magnetic Weyl fermions in Mn3Sn, a non-collinear antiferromagnet that exhibits a large anomalous Hall effect, even at room temperature8. Detailed comparison between angle-resolved photoemission spectroscopy (ARPES) measurements and density functional theory (DFT) calculations reveals significant bandwidth renormalization and damping effects due to the strong correlation among Mn 3d electrons. Magnetotransport measurements provide strong evidence for the chiral anomaly of Weyl fermions—namely, the emergence of positive magnetoconductance only in the presence of parallel electric and magnetic fields. Since weak magnetic fields (approximately 10 mT) are adequate to control the distribution of Weyl points and the large fictitious fields (equivalent to approximately a few hundred T) produced by them in momentum space, our discovery lays the foundation for a new field of science and technology involving the magnetic Weyl excitations of strongly correlated electron systems such as Mn3Sn.

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Figure 1: Magnetic structure and three-dimensional bulk band dispersion in Mn3Sn.
Figure 2: ARPES band mapping near the Fermi level compared to DFT band calculations for Mn3Sn.
Figure 3: Strongly anisotropic magnetoconductance in Mn3Sn.

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References

  1. Nielsen, H. B. & Ninomiya, M. The Adler-Bell-Jackiw anomaly and Weyl fermions in a crystal. Phys. Lett. B 130, 389–396 (1983).

    Article  Google Scholar 

  2. 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, 205101 (2011).

    Article  Google Scholar 

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

    Article  CAS  Google Scholar 

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

    Article  CAS  Google Scholar 

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

    Google Scholar 

  6. Witczak-Krempa, W., Chen, G., Kim, Y. B. & Balents, L. Correlated quantum phenomena in the strong spin-orbit regime. Annu. Rev. Condens. Matter Phys. 5, 57–82 (2014).

    Article  CAS  Google Scholar 

  7. Wang, Z. et al. Time-reversal-breaking Weyl fermions in magnetic Heusler alloys. Phys. Rev. Lett. 117, 236401 (2016).

    Article  Google Scholar 

  8. Nakatsuji, S., Kiyohara, N. & Higo, T. Large anomalous Hall effect in a non-collinear antiferromagnet at room temperature. Nature 527, 212–215 (2015).

    Article  CAS  Google Scholar 

  9. Hasan, M. Z. & Kane, C. L. Colloquium: topological insulators. Rev. Mod. Phys. 82, 3045–3067 (2010).

    Article  CAS  Google Scholar 

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

    Article  CAS  Google Scholar 

  11. Neupane, M. et al. Observation of a three-dimensional topological Dirac semimetal phase in high-mobility Cd3As2 . Nat. Commun. 5, 4786 (2014).

    Article  Google Scholar 

  12. Yang, K.-Y., Lu, Y.-M. & Ran, Y. Quantum Hall effects in a Weyl semimetal: possible application in pyrochlore iridates. Phys. Rev. B 84, 075129 (2011).

    Article  Google Scholar 

  13. Zhong, S., Orenstein, J. & Moore, J. E. Optical gyrotropy from axion electrodynamics in momentum space. Phys. Rev. Lett. 115, 117403 (2015).

    Article  Google Scholar 

  14. Son, D. T. & Spivak, B. Z. Chiral anomaly and classical negative magnetoresistance of Weyl metals. Phys. Rev. B 88, 104412 (2013).

    Article  Google Scholar 

  15. Goswami, P., Pixley, J. H. & Das Sarma, S. Axial anomaly and longitudinal magnetoresistance of a generic three-dimensional metal. Phys. Rev. B 92, 075205 (2015).

    Article  Google Scholar 

  16. Xiong, J. et al. Evidence for the chiral anomaly in the Dirac semimetal Na3Bi. Science 350, 413–416 (2015).

    Article  CAS  Google Scholar 

  17. Huang, X. et al. Observation of the chiral-anomaly-induced negative magnetoresistance in 3D Weyl semimetal TaAs. Phys. Rev. X 5, 031023 (2015).

    Google Scholar 

  18. Zhang, C.-L. et al. Signatures of the Adler-Bell-Jackiw chiral anomaly in a Weyl fermion semimetal. Nat. Commun. 7, 10735 (2016).

    Article  CAS  Google Scholar 

  19. Hirschberger, M. et al. The chiral anomaly and thermopower of Weyl fermions in the half-Heusler GdPtBi. Nat. Mater. 15, 1161–1165 (2016).

    Article  CAS  Google Scholar 

  20. Tomiyoshi, S. Polarized neutron diffraction study of the spin structure of Mn3Sn. J. Phys. Soc. Jpn 51, 803–810 (1982).

    Article  CAS  Google Scholar 

  21. Brown, P., Nunez, V., Tasset, F., Forsyth, J. & Radhakrishna, P. Determination of the magnetic structure of Mn3Sn using generalized neutron polarization analysis. J. Phys. Condens. Matter 2, 9409–9422 (1990).

    Article  CAS  Google Scholar 

  22. Suzuki, M.-T., Koretsune, T., Ochi, M. & Arita, R. Cluster multipole theory for anomalous Hall effect in antiferromagnets. Phys. Rev. B 95, 094406 (2017).

    Article  Google Scholar 

  23. Nagaosa, N., Sinova, J., Onoda, S., MacDonald, A. H. & Ong, N. P. Anomalous Hall effect. Rev. Mod. Phys. 82, 1539–1592 (2010).

    Article  Google Scholar 

  24. Kiyohara, N., Tomita, T. & Nakatsuji, S. Giant anomalous Hall effect in the chiral antiferromagnet Mn3Ge. Phys. Rev. Appl. 5, 064009 (2016).

    Article  Google Scholar 

  25. Yang, H. et al. Topological Weyl semimetals in the chiral antiferromagnetic materials Mn3Ge and Mn3Sn. New J. Phys. 19, 015008 (2017).

    Article  Google Scholar 

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

    Article  CAS  Google Scholar 

  27. McGuire, T. R. & Potter, R. I. Anisotropic magnetoresistance in ferromagnetic 3d alloys. IEEE Trans. Magn. 11, 1018–1038 (1975).

    Article  Google Scholar 

  28. Pippard, A. B. Magnetoresistance in Metals (Cambridge Univ. Press, 1989).

    Google Scholar 

  29. Zyuzin, V. A. Magnetotransport of Weyl semimetals due to the chiral anomaly. Phys. Rev. B 95, 245128 (2017).

    Article  Google Scholar 

  30. Landsteiner, K. Anomalous transport of Weyl fermions in Weyl semimetals. Phys. Rev. B 89, 075124 (2014).

    Article  Google Scholar 

  31. Giannozzi, P. et al. QUANTUM ESPRESSO: a modular and open-source software project for quantum simulations of materials. J. Phys. Condens. Matter 21, 395502 (2009).

    Article  Google Scholar 

Download references

Acknowledgements

This work was supported by CREST (JPMJCR15Q5), Japan Science and Technology Agency, Grants-in-Aid for Scientific Research (Grant Nos. 16H02209, 25707030), by Grants-in-Aid for Scientific Research on Innovative Areas ‘J-Physics’ (Grant Nos. 15H05882 and 15H05883), and ‘Topological Materials Science’ (Grant No. 16H00979), and Grants-in-Aid for Young Scientists A (Grants No. 16H06013) and B (Grants No. 17K14319), and Grant-in-Aid for Exploratory Research (Grants No. 16K13829), and Program for Advancing Strategic International Networks to Accelerate the Circulation of Talented Researchers (Grant No. R2604) from the Japanese Society for the Promotion of Science, and Photon and Quantum Basic Research Coordinated Development Program from the Ministry of Education, Culture, Sports, Science and Technology, Japan. P.G. was supported by JQI-NSF-PFC and LPS-MPO-CMTC. The use of the facilities of the Materials Design and Characterization Laboratory at the Institute for Solid State Physics, The University of Tokyo, is gratefully acknowledged. We thank S. Kunisada, M. Sakano and E. Golias for technical supports to perform ARPES measurements. The soft X-ray synchrotron radiation experiments were performed with the approval of JASRI (Proposal Nos. 2015B2002, 2016A1296, 2016B1262). The vacuum ultraviolet experiments were performed under the approval of the Photon Factory Program Advisory Committee (Proposal No. 2016G622). We thank Helmholtz-Zentrum Berlin (HZB) for the allocation of synchrotron radiation beam time.

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Contributions

S.N. planned the experimental project. K.K. and C.B., conducted the ARPES experiment and analysed the data. M.N., S.A., R.N., S.S., T.Kondo, N.I., K.O., H.K., T.M. and A.V. supported the ARPES experiment. A.A.N., M.I. and S.N. made the Mn3Sn single crystals and carried out their characterization. R.I. performed chemical analyses. T.T., M.I. and S.N. performed transport experiments and collected data. P.G. provided theoretical insights. M.-T.S., T.Koretsune, M.O. and R.A. calculated the band structure. K.K., T.T., P.G., R.A. and S.N. wrote the paper. All the authors discussed the results and commented on the manuscript.

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Correspondence to S. Nakatsuji.

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Kuroda, K., Tomita, T., Suzuki, MT. et al. Evidence for magnetic Weyl fermions in a correlated metal. Nature Mater 16, 1090–1095 (2017). https://doi.org/10.1038/nmat4987

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