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Nodal-chain metals

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Abstract

The band theory of solids is arguably the most successful theory of condensed-matter physics, providing a description of the electronic energy levels in various materials. Electronic wavefunctions obtained from the band theory enable a topological characterization of metals for which the electronic spectrum may host robust, topologically protected, fermionic quasiparticles. Many of these quasiparticles are analogues of the elementary particles of the Standard Model1,2,3,4,5,6,7,8,9,10, but others do not have a counterpart in relativistic high-energy theories11,12,13,14,15,16,17,18. A complete list of possible quasiparticles in solids is lacking, even in the non-interacting case. Here we describe the possible existence of a hitherto unrecognized type of fermionic excitation in metals. This excitation forms a nodal chain—a chain of connected loops in momentum space—along which conduction and valence bands touch. We prove that the nodal chain is topologically distinct from previously reported excitations. We discuss the symmetry requirements for the appearance of this excitation and predict that it is realized in an existing material, iridium tetrafluoride (IrF4), as well as in other compounds of this class of materials. Using IrF4 as an example, we provide a discussion of the topological surface states associated with the nodal chain. We argue that the presence of the nodal-chain fermions will result in anomalous magnetotransport properties, distinct from those of materials exhibiting previously known excitations.

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Figure 1: Catalogue of nodal-chain metals.
Figure 2: Non-symmorphic nodal loop.
Figure 3: Iridium tetrafluoride (IrF4) and its band structure.
Figure 4: Nodal chain and nodal net of IrF4.

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References

  1. Volovik, G. E. The Universe in a Helium Droplet (Oxford Univ. Press, 2003)

  2. Murakami, S. Phase transition between the quantum spin Hall and insulator phases in 3D: emergence of a topological gapless phase. New J. Phys. 9, 356 (2007)

    Article  ADS  Google Scholar 

  3. 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  ADS  Google Scholar 

  4. Young, S. M. et al. Dirac semimetal in three dimensions. Phys. Rev. Lett. 108, 140405 (2012)

    Article  CAS  ADS  Google Scholar 

  5. Wang, Z. et al. Dirac semimetal and topological phase transitions in A3Bi (A=Na, K, Rb). Phys. Rev. B 85, 195320 (2012)

    Article  ADS  Google Scholar 

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

    Article  CAS  ADS  Google Scholar 

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

    Google Scholar 

  8. Huang, S.-M. et al. A Weyl fermion semimetal with surface Fermi arcs in the transition metal monopnictide TaAs class. Nat. Commun. 6, 7373 (2015)

    Article  CAS  ADS  Google Scholar 

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

    Article  CAS  ADS  Google Scholar 

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

    Google Scholar 

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

    Article  CAS  ADS  Google Scholar 

  12. Wang, Z., Alexandradinata, A., Cava, R. J. & Bernevig, B. A. Hourglass fermions. Nature 532, 189–194 (2016)

    Article  CAS  ADS  Google Scholar 

  13. Chang, P.-Y., Erten, O. & Coleman, P. Mobius Kondo insulators. Preprint at http://arxiv.org/abs/1603.03435 (2016)

  14. Wieder, B. J., Kim, Y., Rappe, A. M. & Kane, C. L. Double Dirac semimetals in three dimensions. Phys. Rev. Lett. 116, 186402 (2016)

    Article  ADS  Google Scholar 

  15. Bradlyn, B. et al. Beyond Dirac and Weyl fermions: unconventional quasiparticles in conventional crystals. Science aaf5037 (2016)

    Article  MathSciNet  Google Scholar 

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

    Article  ADS  Google Scholar 

  17. Fang, C., Chen, Y., Kee, H.-Y. & Fu, L. Topological nodal line semimetals with and without spin-orbital coupling. Phys. Rev. B 92, 081201(R) (2015)

    Article  ADS  Google Scholar 

  18. Weng, H. et al. Topological node-line semimetal in three-dimensional graphene networks. Phys. Rev. B 92, 045108 (2015)

    Article  ADS  Google Scholar 

  19. Yang, B.-J. & Nagaosa, N. Classification of stable three-dimensional Dirac semimetals with nontrivial topology. Nat. Commun. 5, 4898 (2014)

    Article  CAS  ADS  Google Scholar 

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

    Article  ADS  MathSciNet  Google Scholar 

  21. 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 

  22. Heikkilä, T. T., Kopnin, N. B. & Volovik, G. E. Flat bands in topological media. JETP Lett. 94, 233– 239 (2011)

    Article  ADS  Google Scholar 

  23. Heikkilä, T. T. & Volovik, G. E. in Basic Physics of Functionalized Graphite (ed. Esquinazi, P. D. ) 123–143 (Springer, 2016)

  24. Young, S. M. & Kane, C. L. Dirac semimetal in two dimensions. Phys. Rev. Lett. 115, 126803 (2015)

    Article  ADS  Google Scholar 

  25. Rhim, J.-W. & Kim, Y. B. Landau level quantization and almost flat modes in three-dimensional semimetals with nodal ring spectra. Phys. Rev. B 92, 045126 (2015)

    Article  ADS  Google Scholar 

  26. Bradley, C. J. & Cracknell, A. P. The Mathematical Theory of Symmetry in Solids (Clarendon Press, 1972)

  27. Rao, P. R., Tressaud, A. & Bartlett, N. The tetrafluorides of iridium, rhodium and palladium. J. Inorg. Nucl. Chem. 28 (Suppl.), 23–28 (1976)

    Article  Google Scholar 

  28. Yudin, D. et al. Fermi condensation near van Hove singularities within the Hubbard model on the triangular lattice. Phys. Rev. Lett. 112, 070403 (2014)

    Article  ADS  Google Scholar 

  29. Kane, C. L. & Mele, E. J. Z2 topological order and the quantum spin Hall effect. Phys. Rev. Lett. 95, 146802 (2005)

    Article  CAS  ADS  Google Scholar 

  30. Habermehl, K. Neue Untersuchungen an Halogeniden des Niobs und Tantals. PhD thesis, Univ. Köln, http://kups.ub.uni-koeln.de/3103/ (2010)

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Acknowledgements

The crystal structures in Fig. 3 were plotted using VESTA 3. We thank A. Bouhon, C. L. Kane, G. E. Volovik, B. A. Bernevig and R. J. Cava for discussions. T.B., A.R. and M.S. acknowledge financial support through an ETH research grant and the Swiss National Science Foundation. Q.S.W. and A.A.S. acknowledge the support of Microsoft Research and the Swiss National Science Foundation through the National Competence Centres in Research MARVEL and QSIT.

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Contributions

T.B. initiated the project, carried out the theoretical analysis and determined the suitable space groups. Q.S.W. discovered the IrF4 material class and performed the first-principle studies. T.B. and A.A.S. wrote the manuscript. All authors contributed to the theoretical discussion and the final version of the manuscript.

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Correspondence to Tomáš Bzdušek.

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The authors declare no competing financial interests.

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Reviewer Information Nature thanks E. Bergholtz, R. Nandkishore and the other anonymous reviewer(s) for their contribution to the peer review of this work.

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This file contains Supplementary Text and Data, Supplementary Figures 1- 8 Supplementary Tables 1- 5 and Supplementary references. (PDF 2158 kb)

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Bzdušek, T., Wu, Q., Rüegg, A. et al. Nodal-chain metals. Nature 538, 75–78 (2016). https://doi.org/10.1038/nature19099

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