Spatially anisotropic Kondo resonance coupled with the superconducting gap in a kagome metal

Nature Physics (2026) Cite this article The chromium-based kagome metal CsCr3Sb5 has garnered broad interest owing to its strong electron correlations, intertwined orders and potential for unconventional superconductivity under high pressure. The evolution of magnetic and superconducting interactions as the more frequently studied CsV3Sb5 is doped to CsCr3Sb5 remains poorly understood. Here we demonstrate the emergence of a spatially anisotropic Kondo resonance intertwined with the superconducting gap, enabled by introducing magnetic Cr impurities into the kagome superconductor CsV3Sb5. The addition of dilute Cr impurities not only weakens the long-range charge density wave order but also produces local magnetic moments, which leads to Kondo resonances. We show that the Kondo resonance forms anisotropic, ripple-like spatial patterns around individual Cr atoms, breaking all local mirror symmetries. We further reveal that, with the emergence of Kondo screening, the coherence peak and depth of the superconducting gap with finite zero-energy conductance are enhanced. This suggests that non-superconducting carriers at the Fermi surface in the parent compound participate in the Kondo effect, simultaneously screening Cr magnetic moments and increasing the superfluid density. Our findings offer an opportunity to study the interplay between superconductivity and local magnetism in kagome materials.This is a preview of subscription content, access via your institution Access Nature and 54 other Nature Portfolio journals Get Nature+, our best-value online-access subscription $32.99 / 30 days cancel any timeSubscribe to this journal Receive 12 print issues and online access $259.00 per yearonly $21.58 per issueBuy this articleUSD 39.95Prices may be subject to local taxes which are calculated during checkoutThe data supporting the findings of this study are available via the Science Data Bank at https://doi.org/10.57760/sciencedb.32867. Additional data are available from the corresponding authors upon reasonable request. Source data are provided with this paper.The code used for STM data analysis is available from the corresponding authors upon reasonable request.Stewart, G. R. Unconventional superconductivity. Adv. Phys. 66, 75–196 (2017).Article ADS Google Scholar Scalapino, D. J. A common thread: the pairing interaction for unconventional superconductors. Rev. Mod. Phys. 84, 1383–1417 (2012).Article ADS Google Scholar Ran, S. et al. Nearly ferromagnetic spin-triplet superconductivity. Science 365, 684–687 (2019).Article ADS Google Scholar Ortiz, B. R. et al. New kagome prototype materials: discovery of KV3Sb5, RbV3Sb3, and CsV3Sb5. Phys. Rev. Mater. 3, 094407 (2019).Article Google Scholar Ortiz, B. R. et al. CsV3Sb5: a Z2 topological kagome metal with a superconducting ground state. Phys. Rev. Lett. 125, 247002 (2020).Article ADS Google Scholar Kang, M. et al. Twofold van Hove singularity and origin of charge order in topological kagome superconductor CsV3Sb5. Nat. Phys. 18, 301–308 (2022).Article Google Scholar Hu, Y. et al. Rich nature of van Hove singularities in Kagome superconductor CsV3Sb5. Nat. Commun. 13, 2220 (2022).Article ADS Google Scholar Yang, S.-Y. et al. Giant, unconventional anomalous Hall effect in the metallic frustrated magnet candidate, KV3Sb5. Sci. Adv. 6, eabb6003 (2020).Article ADS Google Scholar Chen, H. et al. Roton pair density wave in a strong-coupling kagome superconductor. Nature 599, 222–228 (2021).Article ADS Google Scholar Deng, H. et al. Chiral kagome superconductivity modulations with residual Fermi arcs. Nature 632, 775–781 (2024).Article ADS Google Scholar Han, X. et al. Atomic manipulation of the emergent quasi-2D superconductivity and pair density wave in a kagome metal. Nat. Nanotechnol. 20, 1017–1025 (2025).Article ADS Google Scholar Nie, L. et al. Charge-density-wave-driven electronic nematicity in a kagome superconductor. Nature 604, 59–64 (2022).Article ADS Google Scholar Wu, P. et al. Unidirectional electron–phonon coupling in the nematic state of a kagome superconductor. Nat. Phys. 19, 1143–1149 (2023).Article Google Scholar Li, H. et al. Unidirectional coherent quasiparticles in the high-temperature rotational symmetry broken phase of AV3Sb5 kagome superconductors. Nat. Phys. 19, 637–643 (2023).

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The work is supported by grants from the National Natural Science Foundation of China (grant nos. 62488201 to H.-J.G., 92580202 to H.C., 92477205 to W.J. and 52461160327 to W.J.), the National Key Research and Development Projects of China (grant nos. 2022YFA1204100 to H.Y. and H.C. and 2023YFA1406500 to W.J.), the CAS Project for Young Scientists in Basic Research (grant no. YSBR-003 to H.C.) and the Innovation Program of Quantum Science and Technology (grant no. 2021ZD0302700 to H.-J.G., H.C. and H.Y.). Z.W. is supported by the US DOE, Basic Energy Sciences (grant no. DE-FG02-99ER45747) and by Research Corporation for Science Advancement (Cottrell SEED award no. 27856). Calculations (W.J.) were performed at the Physics Lab of High-Performance Computing (PLHPC) and the Public Computing Cloud (PCC) of Renmin University of China.These authors contributed equally: Zichen Huang, Hui Chen, Zhongqin Zhang, Hao Zhang.Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, People’s Republic of ChinaZichen Huang, Hui Chen, Hao Zhang, Zhen Zhao, Ruwen Wang, Haitao Yang & Hong-Jun GaoSchool of Physical Sciences, University of Chinese Academy of Sciences, Beijing, People’s Republic of ChinaZichen Huang, Hui Chen, Hao Zhang, Zhen Zhao, Ruwen Wang, Haitao Yang & Hong-Jun GaoHefei National Laboratory, Hefei, People’s Republic of ChinaHui Chen, Haitao Yang & Hong-Jun GaoBeijing Key Laboratory of Optoelectronic Functional Materials and Micro-Nano Devices, School of Physics, Renmin University of China, Beijing, People’s Republic of ChinaZhongqin Zhang & Wei JiDepartment of Physics, Boston College, Chestnut Hill, MA, USAZiqiang WangSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarSearch author on:PubMed Google ScholarH.-J.G. and H.C. designed the experiments. Z.H., H.C. and H.Z. performed the STM/STS experiments and data analysis. Z. Zhao, R.W. and H.Y. prepared the Cr-doped CsV3Sb5 samples. Z.W. did the theoretical consideration. Z. Zhang and W.J. carried out the theoretical calculations and analysis. Z.H., H.C., Z. Zhang, W.J. and H.-J.G. wrote the paper with input from all authors. H.-J.G. supervised the project.Correspondence to Hui Chen, Wei Ji or Hong-Jun Gao.The authors declare no competing interests.Nature Physics thanks the 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.Supplementary Figs. 1–13 and Text.STM images for the Fourier transfer cut.Kondo resonance peaks with temperature and magnetic field.Statistical source data of Kondo resonance and superconducting gap.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 permissionsHuang, Z., Chen, H., Zhang, Z. et al. Spatially anisotropic Kondo resonance coupled with the superconducting gap in a kagome metal. Nat. Phys. (2026). https://doi.org/10.1038/s41567-026-03292-6Download citationReceived: 27 February 2025Accepted: 14 April 2026Published: 15 May 2026Version of record: 15 May 2026DOI: https://doi.org/10.1038/s41567-026-03292-6Anyone 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