Origin of CDW in Kagome AV3Sb5

ORAL

Abstract

Recently, the kagome superconductor family AV3Sb5 (A = K, Rb, Cs) has been heavily investigated due to its interesting lattice and the occurrence of a charge density wave (CDW). Especially, the origin of the instability and its connection to superconductivity is intensely discussed. Among the most common proposed explanations for the CDW is Fermi surface nesting, influence of van-Hove-singularities and matrix element effects [1,2,3]. However, a clear cut identification is still outstanding.

By utilizing phonon fluctuation diagnostics [4] we try to pinpoint the electronic processes behind phonon softening​. This allows us to disentangle fermiology and matrix-element effects and thereby enhance the understanding of the CDW origin.

[1] M. Kang, et al., Nat. Phys. 18, 301–308 (2022)

[2] X. Wu, et al., Phys. Rev. Lett. 127, 177001

[3] H. Luo, et al., Nat Commun 13, 273 (2022)

[4] J. Berges et al., Phys. Rev. B 101, 155107 (2020)​

* We gratefully acknowledge the Gauss Centre for Supercomputing e.V. (https://www.gauss-centre.eu) for funding this project by providing computing time on the GCS Supercomputer SuperMUC-NG at Leibniz Supercomputing Centre (https://www.lrz.de). We are grateful for funding support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy through the W"urzburg-Dresden Cluster of Excellence on Complexity and Topology in Quantum Matter ct.qmat (EXC 2147, Project ID 390858490), through FOR 5249-449872909 (Project P5) as well as through the Collaborative Research Center SFB 1170 ToCoTronics (Project ID 258499086).

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Presenters

  • Stefan Enzner

    University Wuerzburg

Authors

  • Stefan Enzner

    University Wuerzburg