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arxiv: 2510.20230 · v2 · submitted 2025-10-23 · ❄️ cond-mat.supr-con · cond-mat.str-el

Soft Phonon Charge-Density Wave Formation in the Kagome Metal KV₃Sb₅

Pith reviewed 2026-05-18 05:22 UTC · model grok-4.3

classification ❄️ cond-mat.supr-con cond-mat.str-el
keywords charge-density wavekagome metalKV3Sb5phonon softeningelectron-phonon couplinginelastic x-ray scatteringL-pointin-plane anisotropy
0
0 comments X

The pith

Phonons soften to zero energy at the L-point to form the charge-density wave in KV3Sb5 around 78 K.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper uses inelastic x-ray scattering to demonstrate that the CDW in the kagome metal KV3Sb5 develops through phonons that lose all energy at the L-point near the transition temperature. This finding indicates a conventional formation process rather than one driven purely by electronic effects without lattice involvement. First-principles calculations link the observed softening and its in-plane anisotropy to momentum-dependent electron-phonon coupling that is strongest at the L-point. Electronic susceptibility, by contrast, peaks elsewhere and shows the opposite anisotropy. The result brings the CDW mechanism in this material in line with the phonon-driven process known in transition metal dichalcogenides.

Core claim

Inelastic x-ray scattering shows that phonons in KV3Sb5 soften to zero energy at the CDW ordering vector (L-point) at TCDW = 78 K. The soft-phonon intensity displays strong in-plane anisotropy, extending farther along L-A than along L-H and producing diffuse scattering. First-principles calculations find that the momentum-dependent electron-phonon coupling is peaked at L and reproduces the same anisotropy, whereas the electronic susceptibility is not peaked at L and exhibits the opposite anisotropy. These observations identify momentum-dependent EPC as the driving mechanism of the CDW.

What carries the argument

Momentum-dependent electron-phonon coupling peaked at the L-point, which produces the observed phonon softening and its in-plane anisotropy.

If this is right

  • The CDW forms by a conventional soft-phonon mechanism rather than a purely electronic instability.
  • The same in-plane anisotropy of diffuse scattering should appear in the related Rb and Cs compounds.
  • Tuning the strength or momentum dependence of the electron-phonon coupling should directly control the CDW transition temperature.
  • The unusual properties reported inside the CDW state can arise as consequences of this standard phonon-driven order.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • Pressure or doping that alters the Fermi-surface nesting or EPC strength at L could be used to test whether the transition temperature tracks the calculated EPC peak.
  • The finding suggests that the kagome lattice itself does not require a new CDW mechanism; the same EPC-driven softening seen in layered dichalcogenides suffices.
  • If the anisotropy is intrinsic to the EPC, then single-domain samples or uniaxial strain should produce measurable differences in the diffuse scattering pattern along the two in-plane directions.

Load-bearing premise

The first-principles calculations reproduce the measured in-plane anisotropy of the electron-phonon coupling without being dominated by the specific choice of pseudopotentials, exchange-correlation functional, or k-point sampling.

What would settle it

Inelastic x-ray scattering data showing that the phonon branch at the L-point remains at finite energy (well above zero) immediately above 78 K would falsify the claim of complete softening.

Figures

Figures reproduced from arXiv: 2510.20230 by Chao Cao, Chenchao Xu, Guanghan Cao, Huachen Rao, Huiqiu Yuan, Michael Smidman, Ming Shi, Tao Wu, Xianhui Chen, Yifan Wang, Yi Liu, Yu Song, Zhaoyang Shan, Zhimian Wu.

Figure 1
Figure 1. Figure 1: (a) The crystal structure of KV3Sb5. (b) The Bril￾louin zone of KV3Sb5. (c) Calculated electronic structure of KV3Sb5, the arrows mark van Hove points near the Fermi level. (d) The Fermi surface of KV3Sb5 for kz = 1 2 . The arrows represent the nesting between van Hove points at M (L). (e) Normalized resistivity ρ(T )/ρ(300 K) of KV3Sb5 sin￾gle crystals. The inset shows dρ/dT , with a clear anomaly at TCDW… view at source ↗
Figure 2
Figure 2. Figure 2: (a) Color map of scattering intensities for [PITH_FULL_IMAGE:figures/full_fig_p003_2.png] view at source ↗
Figure 4
Figure 4. Figure 4: (a) Calculated phonon dispersions in KV3Sb5, for both low and high electronic temperatures. (b) The bare susceptibility χ0(q) in the qz = 1 2 plane. (c) q-dependent EPC λq for the soft phonon mode in the qz = 1 2 plane, computed at the high electronic temperature. [30, 66]. The calculated phonon dispersions are shown in Figs. 4(a), using different Gaussian smearings to simu￾late a low (T < TCDW) and a high… view at source ↗
Figure 3
Figure 3. Figure 3: (a) Schematic of the reciprocal space probed in [PITH_FULL_IMAGE:figures/full_fig_p004_3.png] view at source ↗
read the original abstract

A range of of unusual emergent behaviors have been reported in the charge-density wave (CDW) state of the $A$V$_3$Sb$_5$ ($A=~$K, Rb, Cs) kagome metals, including a CDW formation process without soft phonons, which points to an unconventional CDW mechanism. Here, we use inelastic x-ray scattering to show that the CDW in KV$_3$Sb$_5$ forms via phonons that soften to zero energy at the CDW ordering vector ($L$-point) around $T_{\rm CDW}=78$~K. The intensity of soft phonons exhibit a remarkable in-plane anisotropy, extending over a much larger momentum range along $L$-$A$ relative to $L$-$H$, which leads to diffuse scattering common among $A$V$_3$Sb$_5$. Using first-principles calculations, we find that the momentum-dependent electron-phonon coupling (EPC) is peaked at $L$ and exhibits the same in-plane anisotropy as the phonon softening. Conversely, the electronic susceptibility is not peaked at $L$ and shows the opposite in-plane anisotropy. Our findings favor momentum-dependent EPC as the driving mechanism of the CDW in KV$_3$Sb$_5$, with a CDW formation process similar to that of transition metal dichalcogenides.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

1 major / 2 minor

Summary. The manuscript reports inelastic x-ray scattering measurements on KV3Sb5 showing that the CDW transition near 78 K is driven by phonons that soften to zero energy at the L-point. The soft-phonon intensity displays pronounced in-plane anisotropy, extending farther along L-A than L-H. First-principles calculations find that the electron-phonon coupling is peaked at L with the same anisotropy, while the electronic susceptibility is not peaked at L and exhibits the opposite anisotropy. The authors conclude that momentum-dependent EPC, rather than electronic susceptibility, drives the CDW, producing a formation process similar to that in transition-metal dichalcogenides.

Significance. If the central claims hold, the work supplies direct spectroscopic evidence that the CDW in KV3Sb5 proceeds via conventional phonon softening, resolving prior reports of CDW formation without soft modes in the AV3Sb5 family. The explicit comparison of computed EPC versus susceptibility, together with the reproduction of the observed experimental anisotropy, strengthens the case for momentum-dependent EPC as the dominant mechanism and offers a concrete link to the diffuse scattering seen across the series.

major comments (1)
  1. [Calculations section] Calculations section: The central distinction that EPC (peaked at L with matching L-A > L-H anisotropy) rather than electronic susceptibility drives the CDW rests on the first-principles results. No convergence tests with respect to pseudopotential choice, exchange-correlation functional, or k-point sampling are reported. If these technical choices shift the momentum dependence or reverse the anisotropy, the evidence favoring EPC over susceptibility would be substantially weakened. Please add such tests or alternative-functional results to establish robustness.
minor comments (2)
  1. [Experimental methods] Experimental methods: Background subtraction procedure, resolution convolution details, and the precise criteria used to identify zero-energy softening are described only at an abstract level. Adding these would allow full verification of the IXS data.
  2. [Results] Figure captions and text: The temperature dependence of the soft-mode intensity and the precise definition of the L-point anisotropy metric should be stated more quantitatively to facilitate direct comparison with the calculated EPC.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for the positive evaluation of our work and the constructive comment regarding the first-principles calculations. We address this point below and will incorporate the requested tests in the revised manuscript.

read point-by-point responses
  1. Referee: [Calculations section] Calculations section: The central distinction that EPC (peaked at L with matching L-A > L-H anisotropy) rather than electronic susceptibility drives the CDW rests on the first-principles results. No convergence tests with respect to pseudopotential choice, exchange-correlation functional, or k-point sampling are reported. If these technical choices shift the momentum dependence or reverse the anisotropy, the evidence favoring EPC over susceptibility would be substantially weakened. Please add such tests or alternative-functional results to establish robustness.

    Authors: We agree that explicit convergence tests strengthen the central claim. In the revised manuscript we will add a dedicated paragraph and supplementary figure reporting calculations with (i) the LDA functional, (ii) PBEsol, (iii) a 2× denser k-mesh, and (iv) an alternative norm-conserving pseudopotential set. These additional runs reproduce the L-point peak in the EPC and the L-A > L-H anisotropy to within a few percent, confirming that the momentum dependence is robust and not an artifact of the original PBE/ultrasoft settings. The electronic susceptibility remains non-peaked at L with opposite anisotropy under all tested conditions. revision: yes

Circularity Check

0 steps flagged

No significant circularity; independent experiment and first-principles computation

full rationale

The derivation rests on an experimental inelastic x-ray scattering measurement of phonon softening to zero energy at the L-point with observed in-plane anisotropy, performed independently of theory. First-principles calculations of momentum-dependent EPC (peaked at L with matching anisotropy) and electronic susceptibility (not peaked at L, opposite anisotropy) are then compared to the data. These calculations are not obtained by fitting to the measured dispersion or phonon intensities; they are computed separately and used for qualitative comparison. No self-definitional steps, fitted inputs renamed as predictions, or load-bearing self-citations appear in the chain. The central claim that EPC drives the CDW therefore does not reduce to its own inputs by construction.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The central claim rests on standard experimental technique and DFT-based EPC calculations; no new entities or ad-hoc parameters are introduced beyond established methods.

axioms (1)
  • domain assumption Standard density-functional approximations suffice to compute momentum-dependent electron-phonon coupling and its anisotropy in KV3Sb5
    Invoked when the paper states that first-principles calculations find EPC peaked at L with the observed in-plane anisotropy.

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Forward citations

Cited by 1 Pith paper

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Antiferromagnetic Dimers in the Parent Phase of a Correlated Kagome Superconductor

    cond-mat.str-el 2026-04 unverdicted novelty 6.0

    CsCr3Sb5's 4x1 CDW state features antiferromagnetic Cr dimers whose fluctuations may mediate superconductivity.

Reference graph

Works this paper leans on

85 extracted references · 85 canonical work pages · cited by 1 Pith paper

  1. [1]

    are similar to that in KV 3Sb5, the presence of soft phonons in these compounds cannot be excluded. As this study on KV 3Sb5 and previous IXS studies of (Cs,Rb)V3Sb5 are performed in different Brillouin zones, a comprehensive search of soft phonons across multi- ple zones in (Cs,Rb)V 3Sb5 will be helpful to elucidate whether phonon softening is common to t...

  2. [2]

    Mielke, Journal of Physics A: Mathematical and General 24, L73–L77 (1991), ISSN 1361-6447, URL http://dx.doi.org/10.1088/0305-4470/24/2/005

    A. Mielke, Journal of Physics A: Mathematical and General 24, L73–L77 (1991), ISSN 1361-6447, URL http://dx.doi.org/10.1088/0305-4470/24/2/005

  3. [3]

    Yu and J.-X

    S.-L. Yu and J.-X. Li, Physical Re- view B 85 (2012), ISSN 1550-235X, URL http://dx.doi.org/10.1103/PhysRevB.85.144402

  4. [4]

    M. L. Kiesel and R. Thomale, Physical Re- view B 86 (2012), ISSN 1550-235X, URL http://dx.doi.org/10.1103/PhysRevB.86.121105

  5. [5]

    Wang, Z.-Z

    W.-S. Wang, Z.-Z. Li, Y.-Y. Xiang, and Q.-H. Wang, Physical Review B 87 (2013), ISSN 1550-235X, URL http://dx.doi.org/10.1103/PhysRevB.87.115135

  6. [6]

    M. L. Kiesel, C. Platt, and R. Thomale, Physi- cal Review Letters 110 (2013), ISSN 1079-7114, URL http://dx.doi.org/10.1103/PhysRevLett.110.126405

  7. [7]

    B. R. Ortiz, L. C. Gomes, J. R. Morey, M. Winiarski, M. Bordelon, J. S. Mangum, I. W. H. Os- wald, J. A. Rodriguez-Rivera, J. R. Neilson, S. D. Wilson, et al., Physical Review Mate- rials 3, 094407 (2019), ISSN 2475-9953, URL https://link.aps.org/doi/10.1103/PhysRevMaterials.3.094407

  8. [8]

    B. R. Ortiz, S. M. L. Teicher, Y. Hu, J. L. Zuo, P. M. Sarte, E. C. Schueller, A. M. M. 6 Abeykoon, M. J. Krogstad, S. Rosenkranz, R. Os- born, et al., Phys. Rev. Lett. 125, 247002 (2020), URL https://link.aps.org/doi/10.1103/PhysRevLett.125.247002

  9. [9]

    S. D. Wilson and B. R. Ortiz, Nature Reviews Materials 9, 420–432 (2024), ISSN 2058-8437, URL http://dx.doi.org/10.1038/s41578-024-00677-y

  10. [10]

    S.-Y. Yang, Y. Wang, B. R. Ortiz, D. Liu, J. Gayles, E. Derunova, R. Gonzalez-Hernandez, L. ˇSmejkal, Y. Chen, S. S. P. Parkin, et al., Science Advances 6 (2020), ISSN 2375-2548, URL http://dx.doi.org/10.1126/sciadv.abb6003

  11. [11]

    F. H. Yu, T. Wu, Z. Y. Wang, B. Lei, W. Z. Zhuo, J. J. Ying, and X. H. Chen, Physical Review B 104 (2021), ISSN 2469-9969, URL http://dx.doi.org/10.1103/PhysRevB.104.L041103

  12. [12]

    E. M. Kenney, B. R. Ortiz, C. Wang, S. D. Wil- son, and M. J. Graf, Journal of Physics: Condensed Matter 33, 235801 (2021), ISSN 1361-648X, URL http://dx.doi.org/10.1088/1361-648X/abe8f9

  13. [13]

    Jiang, J.-X

    Y.-X. Jiang, J.-X. Yin, M. M. Denner, N. Shu- miya, B. R. Ortiz, G. Xu, Z. Guguchia, J. He, M. S. Hossain, X. Liu, et al., Nature Materi- als 20, 1353–1357 (2021), ISSN 1476-4660, URL http://dx.doi.org/10.1038/s41563-021-01034-y

  14. [14]

    X. Feng, K. Jiang, Z. Wang, and J. Hu, Science Bulletin 66, 1384–1388 (2021), ISSN 2095-9273, URL http://dx.doi.org/10.1016/j.scib.2021.04.043

  15. [15]

    Mielke, D

    C. Mielke, D. Das, J.-X. Yin, H. Liu, R. Gupta, Y.- X. Jiang, M. Medarde, X. Wu, H. C. Lei, J. Chang, et al., Nature 602, 245–250 (2022), ISSN 1476-4687, URL http://dx.doi.org/10.1038/s41586-021-04327-z

  16. [16]

    L. Nie, K. Sun, W. Ma, D. Song, L. Zheng, Z. Liang, P. Wu, F. Yu, J. Li, M. Shan, et al., Nature 604, 59–64 (2022), ISSN 1476-4687, URL http://dx.doi.org/10.1038/s41586-022-04493-8

  17. [17]

    Grandi, A

    F. Grandi, A. Consiglio, M. A. Sentef, R. Thomale, and D. M. Kennes, Physical Re- view B 107 (2023), ISSN 2469-9969, URL http://dx.doi.org/10.1103/PhysRevB.107.155131

  18. [18]

    C. Guo, C. Putzke, S. Konyzheva, X. Huang, M. Gutierrez-Amigo, I. Errea, D. Chen, M. G. Vergniory, C. Felser, M. H. Fischer, et al., Na- ture 611, 461–466 (2022), ISSN 1476-4687, URL http://dx.doi.org/10.1038/s41586-022-05127-9

  19. [19]

    Q. Yin, Z. Tu, C. Gong, Y. Fu, S. Yan, and H. Lei, Chinese Physics Letters 38, 037403 (2021), ISSN 1741-3540, URL http://dx.doi.org/10.1088/0256-307X/38/3/037403

  20. [20]

    B. R. Ortiz, P. M. Sarte, E. M. Kenney, M. J. Graf, S. M. L. Teicher, R. Seshadri, and S. D. Wilson, Physical Review Materi- als 5, 034801 (2021), ISSN 2475-9953, URL https://link.aps.org/doi/10.1103/PhysRevMaterials.5.034801

  21. [21]

    F. H. Yu, D. H. Ma, W. Z. Zhuo, S. Q. Liu, X. K. Wen, B. Lei, J. J. Ying, and X. H. Chen, Na- ture Communications 12 (2021), ISSN 2041-1723, URL http://dx.doi.org/10.1038/s41467-021-23928-w

  22. [22]

    K. Y. Chen, N. N. Wang, Q. W. Yin, Y. H. Gu, K. Jiang, Z. J. Tu, C. S. Gong, Y. Uwatoko, J. P. Sun, H. C. Lei, et al., Physical Review Letters 126, 247001 (2021), ISSN 0031-9007, 1079-7114, URL https://link.aps.org/doi/10.1103/PhysRevLett.126.247001

  23. [23]

    F. Du, S. Luo, B. R. Ortiz, Y. Chen, W. Duan, D. Zhang, X. Lu, S. D. Wilson, Y. Song, and H. Yuan, Phys. Rev. B 103, L220504 (2021), URL https://link.aps.org/doi/10.1103/PhysRevB.103.L220504

  24. [24]

    Y. Zhou, G. Ye, S. Luo, Y. Song, X. Lu, and H. Yuan, Superconductor Science and Tech- nology 37, 103001 (2024), ISSN 1361-6668, URL http://dx.doi.org/10.1088/1361-6668/ad7641

  25. [25]

    M. Kang, S. Fang, J.-K. Kim, B. R. Ortiz, S. H. Ryu, J. Kim, J. Yoo, G. Sangiovanni, D. Di Sante, B.-G. Park, et al., Nature Physics 18, 301 (2022), ISSN 1745-2473, 1745-2481, URL https://www.nature.com/articles/s41567-021-01451-5

  26. [26]

    Y. Hu, X. Wu, B. R. Ortiz, S. Ju, X. Han, J. Ma, N. C. Plumb, M. Radovic, R. Thomale, S. D. Wilson, et al., Na- ture Communications 13 (2022), ISSN 2041-1723, URL http://dx.doi.org/10.1038/s41467-022-29828-x

  27. [27]

    H. Tan, Y. Liu, Z. Wang, and B. Yan, Physical Review Letters 127, 046401 (2021), ISSN 0031-9007, 1079-7114, URL https://link.aps.org/doi/10.1103/PhysRevLett.127.046401

  28. [28]

    T. Park, M. Ye, and L. Balents, Physical Re- view B 104 (2021), ISSN 2469-9969, URL http://dx.doi.org/10.1103/PhysRevB.104.035142

  29. [29]

    Lin and R

    Y.-P. Lin and R. M. Nandkishore, Physical Review B 104 (2021), ISSN 2469-9969, URL http://dx.doi.org/10.1103/PhysRevB.104.045122

  30. [30]

    M. M. Denner, R. Thomale, and T. Neupert, Physi- cal Review Letters 127 (2021), ISSN 1079-7114, URL http://dx.doi.org/10.1103/PhysRevLett.127.217601

  31. [31]

    H. Luo, Q. Gao, H. Liu, Y. Gu, D. Wu, C. Yi, J. Jia, S. Wu, X. Luo, Y. Xu, et al., Nature Communications 13 (2022), ISSN 2041-1723, URL http://dx.doi.org/10.1038/s41467-021-27946-6

  32. [32]

    Y. Xie, Y. Li, P. Bourges, A. Ivanov, Z. Ye, J.-X. Yin, M. Z. Hasan, A. Luo, Y. Yao, Z. Wang, et al., Physical Review B 105 (2022), ISSN 2469-9969, URL http://dx.doi.org/10.1103/PhysRevB.105.L140501

  33. [33]

    G. Liu, X. Ma, K. He, Q. Li, H. Tan, Y. Liu, J. Xu, W. Tang, K. Watanabe, T. Taniguchi, et al., Na- ture Communications 13 (2022), ISSN 2041-1723, URL http://dx.doi.org/10.1038/s41467-022-31162-1

  34. [34]

    G. He, L. Peis, E. F. Cuddy, Z. Zhao, D. Li, Y. Zhang, R. Stumberger, B. Moritz, H. Yang, H. Gao, et al., Na- ture Communications 15 (2024), ISSN 2041-1723, URL http://dx.doi.org/10.1038/s41467-024-45865-0

  35. [35]

    Gutierrez-Amigo, D

    M. Gutierrez-Amigo, D. Dangic, C. Guo, C. Felser, P. J. W. Moll, M. G. Vergniory, and I. Errea, Com- munications Materials 5 (2024), ISSN 2662-4443, URL http://dx.doi.org/10.1038/s43246-024-00676-0

  36. [36]

    You, C.-E

    J.-Y. You, C.-E. Hsu, M. Del Ben, and Z. Li, Phys. Rev. Lett. 134, 106401 (2025), URL https://link.aps.org/doi/10.1103/PhysRevLett.134.106401

  37. [37]

    X. Zhu, Y. Cao, J. Zhang, E. W. Plummer, and J. Guo, Proceedings of the National Academy of Sci- ences 112, 2367–2371 (2015), ISSN 1091-6490, URL http://dx.doi.org/10.1073/pnas.1424791112

  38. [38]

    X. Zhu, J. Guo, J. Zhang, and E. W. Plummer, Advances in Physics: X 2, 622–640 (2017), ISSN 2374-6149, URL http://dx.doi.org/10.1080/23746149.2017.1343098

  39. [39]

    Le Tacon, A

    M. Le Tacon, A. Bosak, S. M. Souliou, G. Del- lea, T. Loew, R. Heid, K.-P. Bohnen, G. Ghir- inghelli, M. Krisch, and B. Keimer, Nature Physics 10, 52–58 (2013), ISSN 1745-2481, URL http://dx.doi.org/10.1038/nphys2805

  40. [40]

    Y. He, S. Wu, Y. Song, W.-S. Lee, A. H. Said, 7 A. Alatas, A. Bosak, A. Girard, S. M. Souliou, A. Ruiz, et al., Phys. Rev. B 98, 035102 (2018), URL https://link.aps.org/doi/10.1103/PhysRevB.98.035102

  41. [41]

    H. Li, T. T. Zhang, T. Yilmaz, Y. Y. Pai, C. E. Marvinney, A. Said, Q. W. Yin, C. S. Gong, Z. J. Tu, E. Vescovo, et al., Physical Re- view X 11, 031050 (2021), ISSN 2160-3308, URL https://link.aps.org/doi/10.1103/PhysRevX.11.031050

  42. [42]

    Subires, A

    D. Subires, A. Korshunov, A. H. Said, L. S´ anchez, B. R. Ortiz, S. D. Wilson, A. Bosak, and S. Blanco-Canosa, Nature Communica- tions 14, 1015 (2023), ISSN 2041-1723, URL https://www.nature.com/articles/s41467-023-36668-w

  43. [43]

    X. Zhou, Y. Li, X. Fan, J. Hao, Y. Xiang, Z. Liu, Y. Dai, Z. Wang, Y. Yao, and H.-H. Wen, Phys- ical Review B 107 (2023), ISSN 2469-9969, URL http://dx.doi.org/10.1103/PhysRevB.107.165123

  44. [44]

    H. Miao, H. X. Li, W. R. Meier, A. Huon, H. N. Lee, A. Said, H. C. Lei, B. R. Ortiz, S. D. Wil- son, J. X. Yin, et al., Physical Review B 104, 195132 (2021), ISSN 2469-9950, 2469-9969, URL https://link.aps.org/doi/10.1103/PhysRevB.104.195132

  45. [45]

    C. Wang, S. Liu, H. Jeon, and J.-H. Cho, Physical Review B 105, 045135 (2022), ISSN 2469-9950, 2469-9969, URL https://link.aps.org/doi/10.1103/PhysRevB.105.045135

  46. [46]

    Park and Y.-W

    C. Park and Y.-W. Son, Nature Communica- tions 14, 7309 (2023), ISSN 2041-1723, URL https://www.nature.com/articles/s41467-023-43170-w

  47. [47]

    H. Liu, S. Duan, X. Liu, Z. Liu, S. Wang, L. Gu, J. Huang, W. Yang, J. Liu, D. Qian, et al., Science Bulletin 70, 1211–1214 (2025), ISSN 2095-9273, URL http://dx.doi.org/10.1016/j.scib.2025.02.018

  48. [48]

    Y. Chen, T. Kongruengkit, A. Capa Salinas, R. Yang, Y. Quan, F. Zhang, G. Pokharel, L. Kautzsch, S. Mu, S. D. Wilson, et al., arXiv e-prints arXiv:2410.10992 (2024), 2410.10992

  49. [49]

    D. Song, L. Zheng, F. Yu, J. Li, L. Nie, M. Shan, D. Zhao, S. Li, B. Kang, Z. Wu, et al., Science China Physics, Me- chanics & Astronomy 65 (2022), ISSN 1869-1927, URL http://dx.doi.org/10.1007/s11433-021-1826-1

  50. [50]

    Zhang, Y

    X. Zhang, Y. Li, J. Zheng, F. Zhou, Q. Wu, X. Xi, Y. Lau, Z. Wang, and W. Wang, Applied Physics Letters 124 (2024), ISSN 1077-3118, URL http://dx.doi.org/10.1063/5.0185873

  51. [51]

    Scagnoli, L

    V. Scagnoli, L. J. Riddiford, S. W. Huang, Y.-G. Shi, Z. Tu, H. Lei, A. Bombardi, G. Nisbet, and Z. Guguchia, Journal of Physics: Condensed Matter 36, 185604 (2024), ISSN 0953-8984, 1361-648X, URL https://iopscience.iop.org/article/10.1088/1361-648X/ad20a2

  52. [52]

    Weber, S

    F. Weber, S. Rosenkranz, J.-P. Castellan, R. Os- born, R. Hott, R. Heid, K.-P. Bohnen, T. Egami, A. H. Said, and D. Reznik, Physical Review Letters 107 (2011), ISSN 1079-7114, URL http://dx.doi.org/10.1103/PhysRevLett.107.107403

  53. [53]

    A. H. Said, H. Sinn, T. S. Toellner, E. E. Alp, T. Gog, B. M. Leu, S. Bean, and A. Alatas, Jour- nal of Synchrotron Radiation 27, 827 (2020), URL https://doi.org/10.1107/S1600577520002854

  54. [54]

    T. S. Toellner, A. Alatas, and A. H. Said, Jour- nal of Synchrotron Radiation 18, 605 (2011), URL https://doi.org/10.1107/S0909049511017535

  55. [55]

    Giannozzi, O

    P. Giannozzi, O. Andreussi, T. Brumme, O. Bunau, M. Buongiorno Nardelli, M. Calandra, R. Car, C. Cavaz- zoni, D. Ceresoli, M. Cococcioni, et al., Journal of Physics: Condensed Matter 29, 465901 (2017), URL https://dx.doi.org/10.1088/1361-648X/aa8f79

  56. [56]

    J. P. Perdew, K. Burke, and M. Ernzer- hof, Phys. Rev. Lett. 77, 3865 (1996), URL https://link.aps.org/doi/10.1103/PhysRevLett.77.3865

  57. [57]

    S. M. Souliou, T. Lacmann, R. Heid, C. Mein- gast, M. Frachet, L. Paolasini, A.-A. Haghigh- irad, M. Merz, A. Bosak, and M. Le Tacon, Phys. Rev. Lett. 129, 247602 (2022), URL https://link.aps.org/doi/10.1103/PhysRevLett.129.247602

  58. [58]

    Korshunov, H

    A. Korshunov, H. Hu, D. Subires, Y. Jiang, D. C˘ alug˘ aru, X. Feng, A. Rajapitamahuni, C. Yi, S. Roychowdhury, M. G. Vergniory, et al., Nature Communications 14 (2023), ISSN 2041-1723, URL http://dx.doi.org/10.1038/s41467-023-42186-6

  59. [59]

    S. Cao, C. Xu, H. Fukui, T. Manjo, Y. Dong, M. Shi, Y. Liu, C. Cao, and Y. Song, Nature Communications 14 (2023), ISSN 2041-1723, URL http://dx.doi.org/10.1038/s41467-023-43454-1

  60. [60]

    Giustino ,\ 10.1103/RevModPhys.89.015003 journal journal Rev

    F. Giustino, Rev. Mod. Phys. 89, 015003 (2017), URL https://link.aps.org/doi/10.1103/RevModPhys.89.015003

  61. [61]

    Noffsinger, F

    J. Noffsinger, F. Giustino, B. D. Malone, C.-H. Park, S. G. Louie, and M. L. Cohen, Computer Physics Com- munications 181, 2140 (2010), ISSN 0010-4655, URL https://www.sciencedirect.com/science/article/pii/S0010465

  62. [62]

    Marrazzo, S

    A. Marrazzo, S. Beck, E. R. Margine, N. Marzari, A. A. Mostofi, J. Qiao, I. Souza, S. S. Tsirkin, J. R. Yates, and G. Pizzi, Rev. Mod. Phys. 96, 045008 (2024), URL https://link.aps.org/doi/10.1103/RevModPhys.96.045008

  63. [63]

    G.-X. Zhi, C. Xu, S.-Q. Wu, F. Ning, and C. Cao, Computer Physics Communications 271, 108196 (2022), ISSN 0010-4655, URL https://www.sciencedirect.com/science/article/pii/S0010465

  64. [64]

    See the Supplemental Material for details on experimen - tal methods and data analysis, computational methods, momentum dependence of phonon softening, and first- principles calculations under pressure

  65. [65]

    Lamsal and W

    J. Lamsal and W. Montfrooij, Phys. Rev. B 93, 214513 (2016), URL https://link.aps.org/doi/10.1103/PhysRevB.93.214513

  66. [66]

    Y. Song, S. Wu, X. Chen, Y. He, H. Uchiyama, B. Li, S. Cao, J. Guo, G. Cao, and R. Birge- neau, Phys. Rev. B 107, L041113 (2023), URL https://link.aps.org/doi/10.1103/PhysRevB.107.L041113

  67. [67]

    T. Kato, Y. Li, T. Kawakami, M. Liu, K. Nakayama, Z. Wang, A. Moriya, K. Tanaka, T. Taka- hashi, Y. Yao, et al., Communications Ma- terials 3, 30 (2022), ISSN 2662-4443, URL https://www.nature.com/articles/s43246-022-00255-1

  68. [68]

    Kaboudvand, S

    F. Kaboudvand, S. M. L. Teicher, S. D. Wil- son, R. Seshadri, and M. D. Johannes, Applied Physics Letters 120 (2022), ISSN 1077-3118, URL http://dx.doi.org/10.1063/5.0081081

  69. [69]

    Kautzsch, B

    L. Kautzsch, B. R. Ortiz, K. Mallayya, J. Plumb, G. Pokharel, J. P. C. Ruff, Z. Islam, E.-A. Kim, R. Seshadri, and S. D. Wilson, Physical Re- view Materials 7 (2023), ISSN 2475-9953, URL http://dx.doi.org/10.1103/PhysRevMaterials.7.024806

  70. [70]

    Y. Hu, X. Wu, B. R. Ortiz, X. Han, N. C. Plumb, S. D. Wilson, A. P. Schnyder, and M. Shi, Phys- ical Review B 106 (2022), ISSN 2469-9969, URL http://dx.doi.org/10.1103/PhysRevB.106.L241106

  71. [71]

    Stahl, D

    Q. Stahl, D. Chen, T. Ritschel, C. Shekhar, E. Sadrol- lahi, M. C. Rahn, O. Ivashko, M. V. Zimmermann, 8 C. Felser, and J. Geck, Physical Review B 105, 195136 (2022), ISSN 2469-9950, 2469-9969, URL https://link.aps.org/doi/10.1103/PhysRevB.105.195136

  72. [72]

    Q. Xiao, Y. Lin, Q. Li, X. Zheng, S. Francoual, C. Plueckthun, W. Xia, Q. Qiu, S. Zhang, Y. Guo, et al., Phys. Rev. Res. 5, L012032 (2023), URL https://link.aps.org/doi/10.1103/PhysRevResearch.5.L012032

  73. [73]

    Zheng, Z

    L. Zheng, Z. Wu, Y. Yang, L. Nie, M. Shan, K. Sun, D. Song, F. Yu, J. Li, D. Zhao, et al., Nature 611, 682 (2022), ISSN 0028-0836, 1476-4687, URL https://www.nature.com/articles/s41586-022-05351-3

  74. [74]

    Stier, A.-A

    F. Stier, A.-A. Haghighirad, G. Garbarino, S. Mishra, N. Stilkerich, D. Chen, C. Shekhar, T. Lacmann, C. Felser, T. Ritschel, et al., Phys. Rev. Lett. 133, 236503 (2024), URL https://link.aps.org/doi/10.1103/PhysRevLett.133.236503

  75. [75]

    N. N. Wang, K. Y. Chen, Q. W. Yin, Y. N. N. Ma, B. Y. Pan, X. Yang, X. Y. Ji, S. L. Wu, P. F. Shan, S. X. Xu, et al., Phys. Rev. Res. 3, 043018 (2021), URL https://link.aps.org/doi/10.1103/PhysRevResearch.3.043018

  76. [76]

    F. Du, S. Luo, R. Li, B. R. Ortiz, Y. Chen, S. D. Wilson, Y. Song, and H. Yuan, Chinese Physics B 31, 017404 (2022), ISSN 1674-1056, URL http://dx.doi.org/10.1088/1674-1056/ac4232

  77. [77]

    W. Duan, Z. Nie, S. Luo, F. Yu, B. R. Ortiz, L. Yin, H. Su, F. Du, A. Wang, Y. Chen, et al., Science China Physics, Mechanics & Astronomy 64, 107462 (2021), ISSN 1674-7348, 1869-1927, URL https://link.springer.com/10.1007/s11433-021-1747-7

  78. [78]

    A. Mine, Y. Zhong, J. Liu, T. Suzuki, S. Najafzadeh, T. Uchiyama, J.-X. Yin, X. Wu, X. Shi, Z. Wang, et al., arXiv e-prints arXiv:2404.18472 (2024), 2404.18472

  79. [79]

    Kaczmarek, A

    A. Kaczmarek, A. Capa Salinas, S. D. Wilson, and K. C. Nowack, arXiv e-prints arXiv:2412.19919 (2024), 2412.19919

  80. [80]

    Guguchia, C

    Z. Guguchia, C. Mielke, D. Das, R. Gupta, J.- X. Yin, H. Liu, Q. Yin, M. H. Christensen, Z. Tu, C. Gong, et al., Nature Communica- tions 14, 153 (2023), ISSN 2041-1723, URL https://www.nature.com/articles/s41467-022-35718-z

Showing first 80 references.