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Massive Dirac fermions in a ferromagnetic kagome metal


The kagome lattice is a two-dimensional network of corner-sharing triangles1 that is known to host exotic quantum magnetic states2,3,4. Theoretical work has predicted that kagome lattices may also host Dirac electronic states5 that could lead to topological6 and Chern7 insulating phases, but these states have so far not been detected in experiments. Here we study the d-electron kagome metal Fe3Sn2, which is designed to support bulk massive Dirac fermions in the presence of ferromagnetic order. We observe a temperature-independent intrinsic anomalous Hall conductivity that persists above room temperature, which is suggestive of prominent Berry curvature from the time-reversal-symmetry-breaking electronic bands of the kagome plane. Using angle-resolved photoemission spectroscopy, we observe a pair of quasi-two-dimensional Dirac cones near the Fermi level with a mass gap of 30 millielectronvolts, which correspond to massive Dirac fermions that generate Berry-curvature-induced Hall conductivity. We show that this behaviour is a consequence of the underlying symmetry properties of the bilayer kagome lattice in the ferromagnetic state and the atomic spin–orbit coupling. This work provides evidence for a ferromagnetic kagome metal and an example of emergent topological electronic properties in a correlated electron system. Our results provide insight into the recent discoveries of exotic electronic behaviour in kagome-lattice antiferromagnets8,9,10 and may enable lattice-model realizations of fractional topological quantum states11,12.

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Figure 1: The kagome structure and Fe3Sn2.
Figure 2: Anomalous Hall response of Fe3Sn2.
Figure 3: Massive Dirac fermion at the zone corner of Fe3Sn2.
Figure 4: Tight binding and hall conductivity of a kagome bilayer.


  1. 1

    O’Keeffe, M. & Hyde, B. G. Crystal Structures. I. Patterns and Symmetry Ch. 5 (Mineralogical Society of America, 1996)

  2. 2

    Sachdev, S. Kagome- and triangular-lattice Heisenberg antiferromagnets: ordering from quantum fluctuations and quantum-disordered ground states with unconfined bosonic spinons. Phys. Rev. B 45, 12377–12396 (1992)

    ADS  CAS  Article  Google Scholar 

  3. 3

    Han, T.-H. et al. Fractionalized excitations in the spin-liquid state of a kagome-lattice antiferromagnet. Nature 492, 406–410 (2012)

    ADS  CAS  Article  Google Scholar 

  4. 4

    Zhou, Y., Kanoda, K. & Ng, T.-K. Quantum spin liquid states. Rev. Mod. Phys. 89, 025003 (2017)

    ADS  MathSciNet  Article  Google Scholar 

  5. 5

    Mazin, I. I. et al. Theoretical prediction of a strongly correlated Dirac metal. Nat. Commun. 5, 4261 (2014)

    ADS  CAS  Article  Google Scholar 

  6. 6

    Guo, H.-M. & Franz, M. Topological insulator on the kagome lattice. Phys. Rev. B 80, 113102 (2009)

    ADS  Article  Google Scholar 

  7. 7

    Xu, G., Lian, B. & Zhang, S.-C. Intrinsic quantum anomalous Hall effect in the kagome lattice Cs2LiMn3F12 . Phys. Rev. Lett. 115, 186802 (2015)

    ADS  Article  Google Scholar 

  8. 8

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

    ADS  CAS  Article  Google Scholar 

  9. 9

    Nayak, A. K. et al. Large anomalous Hall effect driven by a nonvanishing Berry curvature in the noncolinear antiferromagnet Mn3Ge. Sci. Adv. 2, e1501870 (2016)

    ADS  Article  Google Scholar 

  10. 10

    Kuroda, K. et al. Evidence for magnetic Weyl fermions in a correlated metal. Nat. Mater. 16, 1090–1095 (2017)

    ADS  CAS  Article  Google Scholar 

  11. 11

    Tang, E. & Wen, X.-G. High-temperature fractional quantum Hall states. Phys. Rev. Lett. 106, 236802 (2011)

    ADS  Article  Google Scholar 

  12. 12

    Bergholtz, E. J., Liu, Z., Trescher, M., Moessner, R. & Udagawa, M. Topology and interactions in a frustrated slab: tuning from Weyl semimetals to C > 1 fractional Chern insulators. Phys. Rev. Lett. 114, 016806 (2015)

    ADS  CAS  Article  Google Scholar 

  13. 13

    Wallace, P. R. The band theory of graphite. Phys. Rev. 71, 622–634 (1947)

    ADS  CAS  Article  Google Scholar 

  14. 14

    Thouless, D. J., Kohmoto, M., Nightingale, M. P. & den Nijs, M. Quantized Hall conductance in a two-dimensional periodic potential. Phys. Rev. Lett. 49, 405–408 (1982)

    ADS  CAS  Article  Google Scholar 

  15. 15

    Chang, C.-Z. et al. Experimental observation of the quantum anomalous Hall effect in a magnetic topological insulator. Science 340, 167–170 (2013)

    ADS  CAS  Article  Google Scholar 

  16. 16

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

    ADS  Article  Google Scholar 

  17. 17

    Giefers, H. & Nicol, M. High pressure X-ray diffraction study of all FeSn intermetallic compounds and one FeSn solid solution. J. Alloys Compd. 422, 132–144 (2006)

    CAS  Article  Google Scholar 

  18. 18

    Le Caër, G., Malaman, B. & Roques, B. Mössbauer effect study of Fe3Sn2 . J. Phys. F 8, 323–336 (1978)

    ADS  Article  Google Scholar 

  19. 19

    Hou, Z. et al. Observation of various and spontaneous magnetic Skyrmionic bubbles at room temperature in a frustrated kagome magnet with uniaxial magnetic anisotropy. Adv. Mater. 29, 1701144 (2017)

    Article  Google Scholar 

  20. 20

    Kida, T. et al. The giant anomalous Hall effect in the ferromagnet Fe3Sn2—a frustrated kagome metal. J. Phys. Condens. Matter 23, 112205 (2011)

    ADS  CAS  Article  Google Scholar 

  21. 21

    Wang, Q., Sun, S., Zhang, X., Pang, F. & Lei, H. Anomalous Hall effect in a ferromagnetic Fe3Sn2 single crystal with a geometrically frustrated Fe bilayer kagome lattice. Phys. Rev. B 94, 075135 (2016)

    ADS  Article  Google Scholar 

  22. 22

    Tian, Y., Ye, L. & Jin, X. Proper scaling of the anomalous Hall effect. Phys. Rev. Lett. 103, 087206 (2009)

    ADS  Article  Google Scholar 

  23. 23

    Shitade, A. & Nagaosa, N. Anomalous Hall effect in ferromagnetic metals: role of phonons at finite temperature. J. Phys. Soc. Jpn 81, 083704 (2012)

    ADS  Article  Google Scholar 

  24. 24

    Kim, K. S. et al. Coexisting massive and massless Dirac fermions in symmetry-broken bilayer graphene. Nat. Mater. 12, 887–892 (2013)

    ADS  CAS  Article  Google Scholar 

  25. 25

    Sales, B. C., Saparov, B., McGuire, M. A., Singh, D. J. & Parker, D. S. Ferromagnetism of Fe3Sn and alloys. Sci. Rep. 4, 7024 (2014)

    ADS  CAS  Article  Google Scholar 

  26. 26

    Chen, Y. L. et al. Massive Dirac fermion on the surface of a magnetically doped topological insulator. Science 329, 659–662 (2010)

    ADS  CAS  Article  Google Scholar 

  27. 27

    Xu, S. Y. et al. Hedgehog spin texture and Berry’s phase tuning in a magnetic topological insulator. Nat. Phys. 8, 616–622 (2012)

    CAS  Article  Google Scholar 

  28. 28

    Balog, R. et al. Bandgap opening in graphene induced by patterned hydrogen adsorption. Nat. Mater. 9, 315–319 (2010)

    ADS  CAS  Article  Google Scholar 

  29. 29

    Ishii, Y., Harima, H., Okamoto, Y., Yamaura, J. & Hiroi, Z. YCr6Ge6 as a candidate compound for a kagome metal. J. Phys. Soc. Jpn 82, 023705 (2013)

    ADS  Article  Google Scholar 

  30. 30

    Kane, C. L. & Mele, E. J. Quantum spin Hall effect in graphene. Phys. Rev. Lett. 95, 226801 (2005)

    ADS  CAS  Article  Google Scholar 

  31. 31

    Haldane, F. D. M. Model for a quantum Hall effect without Landau levels: condensed-matter realization of the “parity anomaly”. Phys. Rev. Lett. 61, 2015–2018 (1988)

    ADS  MathSciNet  CAS  Article  Google Scholar 

  32. 32

    Drijver, J. W., Sinnema, S. G. & van der Woude, F. Magnetic properties of hexagonal and cubic Fe3Ge. J. Phys. F 6, 2165–2177 (1976)

    ADS  CAS  Article  Google Scholar 

  33. 33

    Fenner, L. A., Dee, A. A. & Wills, A. S. Non-collinearity and spin frustration in the itinerant kagome ferromagnet Fe3Sn2 . J. Phys. Condens. Matter 21, 452202 (2009)

    ADS  CAS  Article  Google Scholar 

  34. 34

    Raquet, B., Viret, M., Sondergard, E., Cespedes, O. & Mamy, R. Electron-magnon scattering and magnetic resistivity in 3d ferromagnets. Phys. Rev. B 66, 024433 (2002)

    ADS  Article  Google Scholar 

  35. 35

    Richard, P. et al. Observation of Dirac cone electronic dispersion in BaFe2As2 . Phys. Rev. Lett. 104, 137001 (2010)

    ADS  CAS  Article  Google Scholar 

  36. 36

    Tan, S. Y. et al. Observation of Dirac cone band dispersions in FeSe thin films by photoemission spectroscopy. Phys. Rev. B 93, 104513 (2016)

    ADS  Article  Google Scholar 

  37. 37

    Bostwick, A., Ohta, T., Seyller, T., Horn, K. & Rotenberg, E. Quasiparticle dynamics in graphene. Nat. Phys. 3, 36–40 (2007)

    CAS  Article  Google Scholar 

  38. 38

    Nevius, M. S. et al. Semiconducting graphene from highly ordered substrate interactions. Phys. Rev. Lett. 115, 136802 (2015)

    ADS  CAS  Article  Google Scholar 

  39. 39

    Damascelli, A., Hussain, Z. & Shen, Z.-X. Angle-resolved photoemission studies of the cuprate superconductors. Rev. Mod. Phys. 75, 473–541 (2003)

    ADS  CAS  Article  Google Scholar 

  40. 40

    Onose, Y. et al. Observation of the magnon Hall effect. Science 329, 297–299 (2010)

    ADS  CAS  Article  Google Scholar 

  41. 41

    Chisnell, R. et al. Topological magnon bands in a kagome lattice ferromagnet. Phys. Rev. Lett. 115, 147201 (2015)

    ADS  CAS  Article  Google Scholar 

  42. 42

    Inami, T., Nishiyama, M., Maegawa, S. & Oka, Y. Magnetic structure of the kagome lattice antiferromagnet potassium jarosite KFe3(OH)6(SO4)2 . Phys. Rev. B 61, 12181–12186 (2000)

    ADS  CAS  Article  Google Scholar 

  43. 43

    Hiroi, Z. et al. Spin-1/2 kagome-like lattice in volborthite Cu3V2O7(OH)2 ∙ 2H2O. J. Phys. Soc. Jpn 70, 3377–3384 (2001)

    ADS  CAS  Article  Google Scholar 

  44. 44

    Qi, X. L., Wu, Y.-S. & Zhang, S.-C. Topological quantization of the spin Hall effect in two-dimensional paramagnetic semiconductors. Phys. Rev. B 74, 085308 (2006)

    ADS  Article  Google Scholar 

  45. 45

    Sinitsyn, N. A., MacDonald, A. H., Jungwirth, T., Dugaev, V. K. & Sinova, J. Anomalous Hall effect in a two-dimensional Dirac band: the link between the Kubo-Streda formula and the semiclassical Boltzmann equation approach. Phys. Rev. B 75, 045315 (2007)

    ADS  Article  Google Scholar 

  46. 46

    Haldane, F. D. M. Berry curvature on the Fermi surface: anomalous Hall effect as a topological Fermi-liquid property. Phys. Rev. Lett. 93, 206602 (2004)

    ADS  CAS  Article  Google Scholar 

  47. 47

    Fang, Z. et al. The anomalous Hall effect and magnetic monopoles in momentum space. Science 302, 92–95 (2003)

    ADS  CAS  Article  Google Scholar 

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We are grateful to X.-G. Wen and E. Tang for discussions. This research was funded in part by the Gordon and Betty Moore Foundation EPiQS Initiative, grant GBMF3848 to J.G.C. and NSF grant DMR-1554891. L.Y., J.L. and F.v.C. acknowledge support by the STC Center for Integrated Quantum Materials, NSF grant number DMR-1231319. L.Y. acknowledges support by the Tsinghua Education Foundation. M.K. acknowledges a Samsung Scholarship from the Samsung Foundation of Culture. This research used resources of the Advanced Light Source, which is a DOE Office of Science User Facility under contract number DE-AC02-05CH11231. A portion of this work was performed at the National High Magnetic Field Laboratory, which is supported by NSF cooperative agreement number DMR-1157490, the State of Florida and the US Department of Energy.

Author information




L.Y., T.S. and C.R.W. grew the single crystals. L.Y. characterized the materials, performed the transport and magnetic measurements and analysed the resultant data. M.K., C.J., A.B. and E.R. performed the ARPES experiment and analysed the resultant data. J.L. and L.Y. performed the theoretical calculations. F.v.C. and D.C.B. performed the electron microscopy study. All authors contributed to writing the manuscript. L.F., R.C. and J.G.C. supervised the project.

Corresponding authors

Correspondence to Riccardo Comin or Joseph G. Checkelsky.

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The authors declare no competing financial interests.

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Reviewer Information Nature thanks E. Bergholtz, B. Lake and O. Rader for their contribution to the peer review of this work.

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Extended data figures and tables

Extended Data Figure 1 Metallic transport in Fe3Sn2.

a, Resistivity ρ as a function of temperature T in the kagome plane for Fe3Sn2 sample C1. The inset shows a photograph of Fe3Sn2 single crystals. b, c, Magnetoresistance (defined as MR = [ρxx(B) − ρxx(0)]/ρxx(0)) at selected T with B applied perpendicular (b) or parallel (c) to the kagome plane and B I (schematics of the configurations are shown as insets).

Extended Data Figure 2 Extracting anomalous Hall conductivity and high-field transport.

a, In-plane Hall conductivity σxy as a function of magnetic induction B at selected temperatures. Dashed lines represent the linear fit to . The data at 2 K and 50 K have been scaled by the factors shown for clarity. b, Magnetoresistance (main panel) and Hall effect (inset) of Fe3Sn2 with applied magnetic field μ0H c up to 31 T.

Extended Data Figure 3 Momentum and energy-dependent band structure along high-symmetry directions.

a, e, Fermi surface of Fe3Sn2 obtained from different experimental geometries. bd, f, g, Band dispersion of Fe3Sn2 along high-symmetry directions. The panels correspond to the momentum directions along the red (b), orange (c), green (d), magenta (f) and purple (g) dotted lines in a and e. The inset in d shows the raw data of Fig. 3c (with the same energy and momentum range), highlighting the spectral weight distribution near the Dirac points. h, Energy distribution curves at different K points indicated in c, d, f and g. The curves are shifted along the vertical direction for clarity. The inset shows an example of Gaussian fits; the extracted gap size is Δ = 30 ± 5 meV.

Extended Data Figure 4 Photon-energy dependence of ARPES spectra.

ARPES intensity plot for Fe3Sn2 taken along the Γ–K direction as a function of binding energy k and photon energy.

Extended Data Figure 5 Berry curvature and Hall conductivity for a massive Dirac fermion.

ac, Schematics of 2D Dirac fermions and the corresponding Bloch-sphere representation of the wavefunction of filled states for the gapless case (a) and the gapped case with EF in (b) and out of (c) the gap. d, Fermi energy EF dependence of σxy for the case of a single massive Dirac fermion with gap Δ and Fermi velocity vF.

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Ye, L., Kang, M., Liu, J. et al. Massive Dirac fermions in a ferromagnetic kagome metal. Nature 555, 638–642 (2018).

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