Loop-current order in kagome metals

Nature Physics (2026)Cite this article Loop-current states arise when interacting electronic degrees of freedom collectively generate interatomic currents, producing a rare form of magnetic order in which spin does not play the primary role. The recent proposal of loop-current states in kagome superconductors has stimulated renewed interest in this exotic type of magnetism. We provide an overview of the phenomenological and symmetry properties of loop currents, as well as relevant microscopic models and ab initio methods in kagome materials. We then discuss how loop-current order generates a spin density wave through spin–orbit coupling and a charge density wave through anharmonic couplings present in systems with three-fold rotational symmetry. 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R.M.F. was supported by the Air Force Office of Scientific Research under award no. FA9550-21-1-0423. D.V. was supported by NSF grant no. DMR-2421845. T.B. was supported by the NSF CAREER grant no. DMR2046020.Department of Physics, The Grainger College of Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USARafael M. FernandesAnthony J. Leggett Institute for Condensed Matter Theory, The Grainger College of Engineering, University of Illinois Urbana-Champaign, Urbana, IL, USARafael M. FernandesDepartment of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN, USATuran BirolDepartment of Physics and Astronomy, University of Utah, Salt Lake City, UT, USAMengxing YeDepartment of Physics and Astronomy, Rutgers University, Piscataway, NJ, USADavid VanderbiltCenter for Materials Theory, Rutgers University, Piscataway, NJ, USADavid VanderbiltSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarAll authors wrote the manuscript.Correspondence to Rafael M. Fernandes, Turan Birol, Mengxing Ye or David Vanderbilt.The authors declare no competing interests.Nature Physics thanks Dongwook Go 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.Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.Reprints and permissionsFernandes, R.M., Birol, T., Ye, M. et al. Loop-current order in kagome metals. Nat. Phys. (2026). https://doi.org/10.1038/s41567-026-03229-zDownload citationReceived: 10 February 2025Accepted: 25 February 2026Published: 16 April 2026Version of record: 16 April 2026DOI: https://doi.org/10.1038/s41567-026-03229-zAnyone you share the following link with will be able to read this content:Sorry, a shareable link is not currently available for this article. Provided by the Springer Nature SharedIt content-sharing initiative