Emergent relativistic quasiparticles in Weyl semimetals are the source of exotic electronic properties such as surface Fermi arcs, the anomalous Hall effect and negative magnetoresistance, all observed in real materials. Whereas these phenomena highlight the effect of Weyl fermions on the electronic transport properties, less is known about what collective phenomena they may support. Here, we report a Weyl semimetal, NdAlSi, that offers an example. Using neutron diffraction, we found a long-wavelength helical magnetic order in NdAlSi, the periodicity of which is linked to the nesting vector between two topologically non-trivial Fermi pockets, which we characterize using density functional theory and quantum oscillation measurements. We further show the chiral transverse component of the spin structure is promoted by bond-oriented Dzyaloshinskii–Moriya interactions associated with Weyl exchange processes. Our work provides a rare example of Weyl fermions driving collective magnetism.
This is a preview of subscription content, access via your institution
Open Access articles citing this article.
Nature Communications Open Access 08 November 2023
Nature Communications Open Access 25 August 2023
Communications Physics Open Access 09 June 2023
Access Nature and 54 other Nature Portfolio journals
Get Nature+, our best-value online-access subscription
$29.99 / 30 days
cancel any time
Subscribe to this journal
Receive 12 print issues and online access
$259.00 per year
only $21.58 per issue
Rent or buy this article
Prices vary by article type
Prices may be subject to local taxes which are calculated during checkout
All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Information. Additional data related to this paper may be requested from the authors.
Armitage, N. P., Mele, E. J. & Ashvin, V. Weyl and Dirac semimetals in three-dimensional solids. Rev. Mod. Phys. 90, 015001 (2018).
Wan, X., Turner, M. A., Vishwanath, A. & Savrasov, S. Y. Topological semimetal and Fermi-arc surface states in the electronic structure of pyrochlore iridates. Phys. Rev. B 83, 205101 (2015).
Lv, B. Q. et al. Experimental discovery of Weyl semimetal TaAs. Phys. Rev. X 5, 031013 (2015).
Yang, L. X. et al. Weyl semimetal phase in the non-centrosymmetric compound TaAs. Nat. Phys. 11, 728–732 (2015).
Xu, S.-Y. et al. Discovery of a Weyl fermion semimetal and topological Fermi arcs. Science 349, 613–617 (2015).
Nakatsuji, S., Kiyohara, N. & Higo, T. Large anomalous Hall effect in a non-collinear antiferromagnet at room temperature. Nature 527, 212–215 (2015).
Kim, K. et al. Large anomalous Hall current induced by topological nodal lines in a ferromagnetic van der Waals semimetal. Nat. Mater. 17, 794–799 (2018).
Sakai, A. et al. Giant anomalous Nernst effect and quantum-critical scaling in a ferromagnetic semimetal. Nat. Phys. 14, 1119–1124 (2018).
Liu, D. F. et al. Magnetic Weyl semimetal phase in a Kagomé crystal. Science 365, 1282–1285 (2019).
Liu, E. et al. Giant anomalous Hall effect in a ferromagnetic kagome-lattice semimetal. Nat. Phys. 14, 1125–1131 (2018).
Belopolski, I. et al. Discovery of topological Weyl fermion lines and drumhead surface states in a room temperature magnet. Science 365, 1278–1281 (2019).
Chang, G. et al. Magnetic and noncentrosymmetric Weyl fermion semimetals in the RAlGe family of compounds (R = rare earth). Phys. Rev. B 97, 041104 (2018).
Suzuki, T. et al. Singular angular magnetoresistance in a magnetic nodal semimetal. Science 365, 377–381 (2019).
Puphal, P. et al. Topological magnetic phase in the candidate Weyl semimetal CeAlGe. Phys. Rev. Lett. 124, 017202 (2020).
Yang, H. Y. et al. Noncollinear ferromagnetic Weyl semimetal with anisotropic anomalous Hall effect. Phys. Rev. B 103, 115143 (2021).
Wei, H. et al. Crystal structural refinement for NdAlSi. Rare Metals 25, 355–358 (2006).
Lin, H., Rebelsky, L., Collins, M. F., Garret, J. D. & Buyers, W. J. L. Magnetic structure of UNi2Si2. Phys. Rev. B 43, 13232 (1991).
Wu, S. et al. Incommensurate magnetism near quantum criticality in CeNiAsO. Phys. Rev. Lett. 122, 197203 (2019).
Rossat-Mignod, J. et al. Phase diagram and magnetic structures of CeSb. Phys. Rev. B 16, 440–461 (1977).
Gignoux, D. & Schmitt, D. Competition between commensurate and incommensurate phases in rare-earth systems: effects on H-T magnetic phase diagrams. Phys. Rev. B 48, 12682 (1993).
Taylor, K. N. R. Intermetallic rare-earth compounds. Adv. Phys. 20, 551–660 (1971).
Jensen, J. & Mackintosh, A. R. Rare Earth Magnetism (Clarendon Press, 1991).
Anisimov, V. I., Aryasetiawan, F. & Lichtenstein, A. I. First-principles calculations of the electronic structure and spectra of strongly correlated systems: the LDA+ U method. J. Phys. Condens. Matter 9, 767 (1997).
Pizzi, G. et al. Wannier90 as a community code: new features and applications. J. Phys. Condens. Matter 31, 165902 (2020).
Hosseini, M. V. & Askari, M. Ruderman-Kittel-Kasuya-Yosida interaction in Weyl semimetals. Phys. Rev. B 92, 224435 (2015).
Chang, H.-R., Zhou, J., Wang, S.-X., Shan, W.-Y. & Di, X. RKKY interaction of magnetic impurities in Dirac and Weyl semimetals. Phys. Rev. B 92, 241103(R) (2015).
Araki, Y. & Nomura, K. Spin textures and spin-wave excitations in doped Dirac-Weyl semimetals. Phys. Rev. B 93, 094438 (2016).
Wang, S.-X., Hao-Ran Chang, H.-R. & Chang, H.-R. RKKY interaction in three-dimensional electron gases with linear spin-orbit coupling. Phys. Rev. B 96, 115204 (2017).
Nikolić, P. Quantum field theory of topological spin dynamics. Phys. Rev. B 102, 075131 (2020).
Nikolić, P. Dynamics of local magnetic moments induced by itinerant Weyl electrons. Phys. Rev. B 103, 155151 (2021).
Schultz, A. J. et al. Integration of neutron time-of-flight single-crystal Bragg peaks in reciprocal space. J. Appl. Crystallogr. 47, 915–921 (2014).
Toby, G. H. & Von Dreele, R. B. GSAS-II: the genesis of a modern open-source all purpose crystallography software package. J. Appl. Crystallogr. 46, 544–549 (2013).
Kresse, G. & Furthmüller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169 (1996).
Kresse, G. & Joubert, D. From ultrasoft pseudopotentials to the projector augmented-wave method. Phys. Rev. B 59, 11758 (1999).
Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 11758 (1996).
Wu, Q., Zhang, S., Song, H.-F., Troyer, M. & Soluyanov, A. A. WannierTools: an open-source software package for novel topological materials. Comput. Phys. Commun. 224, 405–416 (2018).
This work was supported as part of the Institute for Quantum Matter, an Energy Frontier Research Center funded by the US Department of Energy, Office of Science, Basic Energy Sciences under award no. DE-SC0019331. The work at Boston College was funded by the National Science Foundation under award no. DMR-1708929. C.L.B. and J.G. were supported by the Gordon and Betty Moore Foundation through GBMF9456. A portion of this work was performed at the National High Magnetic Field Laboratory, which is supported by the National Science Foundation Cooperative Agreement no. DMR-1644779 and the state of Florida. We also acknowledge the support of the National Institute of Standards and Technology, US Department of Commerce. The identification of any commercial product or trade name does not imply endorsement or recommendation by the National Institute of Standards and Technology. Access to MACS was provided by the Center for High Resolution Neutron Scattering, a partnership between the National Institute of Standards and Technology and the National Science Foundation under agreement no. DMR-1508249. A portion of this research used resources at the Spallation Neutron Source, a Department of Energy Office of Science User Facility operated by the Oak Ridge National Laboratory. S.B. thanks J. Kim for fruitful discussions on the symmetric Wannier function generations from Wannier90. We thank Y. Li for useful discussions. We are also grateful to Y. Chen, Y. Luo, C. Lygouras and Y. Vekhov for their help during neutron scattering experiments.
The authors declare no competing interests.
Peer review information Nature Materials thanks Philippe Bourges and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
About this article
Cite this article
Gaudet, J., Yang, HY., Baidya, S. et al. Weyl-mediated helical magnetism in NdAlSi. Nat. Mater. 20, 1650–1656 (2021). https://doi.org/10.1038/s41563-021-01062-8
This article is cited by
npj Quantum Materials (2023)
Communications Physics (2023)
Nature Communications (2023)
Nature Communications (2023)
Sign-tunable anisotropic magnetoresistance and electrically detectable dual magnetic phases in a helical antiferromagnet
NPG Asia Materials (2022)