Pith. sign in

REVIEW 2 major objections 6 minor 47 references

Phonon scattering mechanisms in WTe$_2$ observed by ultrafast coherent phonon spectroscopy

T0 review · 2 major / 6 minor · reviewed 2026-07-09 · glm-5.2

Pith's one-line read Phonon-electron scattering drives anomalous 2.4 THz mode in WTe₂

desk verdict Coherent phonon spectroscopy identifies the 2.4 THz mode in WTe₂ as a phonon-electron scattering channel, but the model rests on a parallel-band simplification that is not independently validated. read the letter →

arxiv 2607.07087 v1 pith:C3BNVOJ6 submitted 2026-07-08 cond-mat.mtrl-sci

classification cond-mat.mtrl-sci PACS 63.20.kk78.47.J63.20.D71.18.+y
keywords phononscatteringmechanismstemperaturecoherentdependenceopticalspectroscopy
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

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

The reading

The paper claims that in the Weyl semimetal Td-WTe₂, the lowest-frequency intralayer optical phonon (2.4 THz) scatters through a channel absent in higher-frequency modes of the same crystal: direct decay into electron-hole pairs via interband transitions. This phonon-electron scattering produces anomalous, non-monotonic temperature dependence in both the phonon frequency and lifetime, with a critical point near 100 K that may coincide with the Lifshitz transition — a topological reshaping of the Fermi surface. The authors isolate this channel by showing that conventional anharmonic phonon-phonon models fit the two higher-frequency modes (4.9 and 6.3 THz) but fail for the 2.4 THz mode, while a combined phonon-phonon plus phonon-electron model reproduces all data. They further show that the phonon-electron contribution weakens with increasing photoexcited carrier density, consistent with screening of the electron-phonon coupling. The key physical reasoning is that the lowest-frequency phonon has the strongest electron-phonon coupling (scaling as the inverse square root of frequency) and the longest intrinsic lifetime, making phonon-electron scattering the dominant decay channel below the Debye temperature.

What carries the argument

Ultrafast pump-probe coherent phonon spectroscopy (Ti:sapphire oscillator, 830 nm, 30 fs pulses) measuring transient reflectivity changes from 4.6–300 K; damped harmonic oscillator fitting of time-domain phonon signals; Klemens and Balkanski anharmonic phonon-phonon models; a phenomenological phonon-electron scattering model assuming parallel electronic bands, where the scattering rate depends on the difference of two Fermi-Dirac distributions; fluence-dependent measurements from 3–100 µJ/cm² to separate phonon-phonon and phonon-electron contributions.

What would settle it

If the anomalous temperature dependence of the 2.4 THz mode were measured to vanish under conditions where the electronic structure is modified (e.g., by gating, pressure, or chemical doping) without a corresponding change in phonon-phonon scattering, this would support the phonon-electron interpretation. Conversely, if a more realistic band-structure calculation of the phonon-electron scattering rate (without the parallel-band assumption) failed to reproduce the observed critical point near 100 K, the interpretation would be undermined.

Watch

Extended reading notes

Core claim

The 2.4 THz A₁ optical phonon in Td-WTe₂ decays predominantly through phonon-electron scattering — the creation of electron-hole pairs via interband transitions — rather than through the conventional anharmonic phonon-phonon processes that govern higher-frequency modes in the same material. This channel produces anomalous temperature dependence with a critical point near 100 K, possibly linked to the Lifshitz transition, and can be tuned by photoexcited carrier density through screening of the electron-phonon interaction.

Load-bearing premise

The model for phonon-electron scattering assumes that the relevant electronic bands are parallel, so that the phonon energy matches the interband gap for all electron momenta. This simplifies the actual tilted Weyl cone band structure of WTe₂, and the fitted energy parameter is not independently checked against measured band structures. If the bands are not parallel, the extracted phonon-electron scattering contribution could partly reflect the fitting form rather than the真正的

Editorial extensions

If this is right

  • If phonon-electron scattering is the dominant decay channel for low-frequency phonons in WTe₂, then thermal transport and optoelectronic response at low temperatures are governed by electronic structure rather than lattice anharmonicity.
  • The ability to tune the phonon-electron scattering rate by photoexcited carrier density suggests a route to optically controlling phonon lifetimes and, by extension, the dynamical Lifshitz transition in WTe₂.
  • The same methodology — comparing temperature-dependent phonon frequency and decay rate against anharmonic models to isolate phonon-electron contributions — could be applied to other Weyl semimetals and topological materials where electronic structure changes are expected.
  • The critical temperature near 100 K for the phonon anomaly, if confirmed to coincide with the Lifshitz transition in bulk samples, would provide a phonon-spectroscopic signature of Fermi surface topology changes.
Share X Bluesky LinkedIn Reddit HN

Signed reviews

No signed human review yet.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

2 major / 6 minor

Summary. This manuscript reports ultrafast pump-probe coherent phonon spectroscopy on Td-WTe₂ over 4.6–300 K, analyzing the temperature dependence of three intralayer A₁ optical phonon modes (ω₂ ≈ 2.4 THz, ω₆ ≈ 4.9 THz, ω₇ ≈ 6.3 THz). The two high-frequency modes are well described by conventional anharmonic phonon-phonon scattering (Klemens three-phonon and Balkanski three-plus-four-phonon models). The low-frequency ω₂ mode exhibits non-monotonic temperature dependence in both frequency and decay rate, which the authors attribute to phonon-electron scattering via interband transitions, modeled phenomenologically by Eqs. (8)–(9). Fluence-dependent measurements (3–100 µJ/cm²) show that the phonon-electron scattering contribution decreases with increasing fluence, interpreted as carrier screening of the electron-phonon coupling. The critical point near 100 K in the ω₂ decay rate is tentatively associated with a Lifshitz transition.

Significance. The identification of a phonon-electron scattering channel in a type-II Weyl semimetal, distinguished from conventional anharmonic decay by its non-monotonic temperature signature, is a useful contribution to the understanding of electron-phonon coupling in topological semimetals. The fluence-dependent cross-check (Fig. 5), showing opposite trends for phonon-phonon and phonon-electron terms, provides an internally consistent argument that strengthens the screening interpretation. The approach is applicable to other Weyl semimetal systems and the experimental methodology is sound. However, the central claim rests on a phenomenological model whose physical assumptions require further validation, as detailed below.

major comments (2)
  1. The fitted value of ℏωₐ in Eqs. (8)–(9) is not reported or compared to ARPES-measured band energies. This parameter represents the energy of the initial electronic state relative to the Fermi level and is central to interpreting the phonon-electron scattering channel as an interband transition. Without reporting the fitted value and validating it against known electronic structure (e.g., the ARPES data from Refs. [5, 6, 17]), the reader cannot assess whether the extracted energy scale corresponds to a real electronic transition. The authors should report ℏωₐ and discuss its physical plausibility. This is load-bearing because the identification of phonon-electron scattering depends on the fitted term having a physically meaningful energy scale rather than being a flexible fitting parameter.
  2. The reduction from the full Fermi golden rule expression (Eq. 6) to the phenomenological two-Fermi-Dirac-difference form (Eqs. 8–9) assumes parallel electronic bands. For Td-WTe₂, a type-II Weyl semimetal with tilted Weyl cones and separate electron/hole pockets, this is a substantial simplification. The model for ω₂ simultaneously fits frequency and decay rate with 7 free parameters (ω₀, ω₃ph, ω_ph-e, ωₐ, Γ₀, Γ₃ph, Γ_ph-e), which provides considerable flexibility to reproduce non-monotonic behavior. The authors should explicitly discuss the parallel-band assumption, state its limitations for WTe₂'s band structure, and address whether alternative scattering mechanisms or fitting forms could produce comparable agreement. At minimum, an acknowledgment of this assumption's scope and a comparison of ℏωₐ to band structure data would substantially strengthen the claim.
minor comments (6)
  1. In the text following Eq. (9), the fitting parameters are listed as 'ω_ph-ph, ω_ph-e, Γ_ph-ph and Γ_ph-e' but the equations use ω₃ph and Γ₃ph. Please use consistent notation.
  2. The authors note that Figs. 3(e,f) and 5(a,b) show slight deviations in the ω₂ data at 10 µJ/cm² between different measurement runs. It would help to quantify or show the magnitude of this discrepancy, or state whether error bars encompass the run-to-run variation.
  3. The statement that the phonon lifetime of ω₂ is 'extremely long (~34 ps at 4.6 K)' — please clarify whether this refers to the total lifetime or the phonon-phonon contribution, and how it compares to other modes over the temperature range.
  4. The Debye temperature of WTe₂ (≈133 K, Ref. [33]) is cited as relevant to the regime where phonon-electron scattering dominates over phonon-phonon scattering for ω₂. A brief comment on why the Debye temperature is the relevant crossover scale for an optical mode at 2.4 THz would help readers.
  5. Fig. 2(b): the color map shows normalized FT amplitude, but the normalization scheme is not specified. Please state whether normalization is to the peak amplitude at each temperature or globally.
  6. The claim that the critical point near 100 K 'may be induced by the Lifshitz transition' is stated somewhat cautiously. Given that the proposed Lifshitz transition temperature varies with sample thickness and the sample here is bulk (~100 µm), a brief discussion of why the thicker-sample transition temperature applies would clarify the argument.

Circularity Check

0 steps flagged · score 1.0 of 10

No significant circularity; standard phenomenological fitting with externally-sourced models

full rationale

The paper's central claim — that phonon-electron scattering contributes to the anomalous temperature dependence of the 2.4 THz mode — rests on fitting a phenomenological model (Eqs. 8–9) sourced from external work (Ref. [32], Hou et al.) to experimental data. The full Fermi golden rule (Eq. 6) is cited from Ref. [29] (Bonini et al., external). The electron-phonon coupling argument uses external tr-ARPES data (Ref. [17], Hein et al.). The screening interpretation cites external works [42, 43]. No derivation step reduces to its own input by construction: the phonon-electron term has a specific functional form (difference of two Fermi-Dirac distributions) that produces non-monotonic behavior the pure phonon-phonon term cannot, so the good fit carries genuine (if not conclusive) evidential weight. The fluence-dependent cross-check refits the same model at each fluence, which is a mild concern since parameter trends could reflect redistribution between fitting terms rather than cleanly isolating the scattering channel — but the opposite trends of Γ_3ph (increasing) and Γ_ph-e (decreasing) with fluence are non-trivial and consistent with the physical picture. The paper does not claim parameter-free predictions; it presents fitted results as evidence supporting an interpretation, with appropriate hedging ('may be induced by the Lifshitz transition'). The parallel-band simplification and 7-parameter fit flexibility are model-validity concerns (correctness risk), not circularity. Score 1 reflects the minor concern that the fluence cross-check reuses the same fitted functional form, but this does not make the central claim circular by construction.

Assumptions & free parameters 9 free parameters · 4 assumptions · 0 invented entities

No new particles, forces, or entities are postulated. The models use standard phonon-phonon and phonon-electron scattering formalism. The free parameters are all fitted coefficients within these established frameworks. The key concern is that ℏω_a is a fitted energy scale without independent electronic structure validation on the same sample.

free parameters (9)
  • ω_0 (per mode) = varies by mode
    Phonon frequency at 0 K, fitted for each mode in Eqs. (2), (4), (8).
  • ω_3ph (per mode) = e.g. -0.00457 THz for ω7
    Three-phonon scattering frequency shift coefficient, fitted in Eqs. (2), (4), (8).
  • ω_4ph (ω7 mode) = -0.0000320 THz
    Four-phonon scattering frequency shift coefficient, fitted in Eq. (4) for ω7.
  • Γ_0 (per mode) = varies by mode
    Decay rate at 0 K, fitted for each mode in Eqs. (3), (5), (9).
  • Γ_3ph (per mode) = e.g. 0.00138 THz for ω7
    Three-phonon decay rate coefficient, fitted in Eqs. (3), (5), (9).
  • Γ_4ph (ω7 mode) = 0.000176 THz
    Four-phonon decay rate coefficient, fitted in Eq. (5) for ω7.
  • ω_ph-e (ω2 mode) = not numerically stated
    Phonon-electron scattering frequency shift coefficient, fitted in Eq. (8).
  • Γ_ph-e (ω2 mode) = not numerically stated
    Phonon-electron scattering decay rate coefficient, fitted in Eq. (9).
  • ℏω_a (ω2 mode) = not numerically stated
    Energy of initial electron state relative to Fermi energy, fitted in Eqs. (8)-(9). Not independently validated against ARPES.
assumptions (4)
  • domain assumption Parallel electronic band approximation for interband transitions
    Eq. (6) is simplified to the form in Eqs. (8)-(9) by assuming parallel bands so that ℏω_q = ε(k+q)j - ε_ki holds for all k. This is stated in the text between Eqs. (7) and (8).
  • domain assumption Klemens model for three-phonon decay
    Eqs. (2)-(3) assume an optical phonon decays into two acoustic phonons of equal frequency with opposite wave vectors. Standard model from Ref. 20.
  • domain assumption Balkanski model for four-phonon decay
    Eqs. (4)-(5) extend the Klemens model with a four-phonon process. Standard model from Ref. 22.
  • domain assumption Carrier screening suppresses electron-phonon coupling in bulk TMDs
    The fluence-dependent decrease of Γ_ph-e is attributed to screening by photogenerated carriers, supported by Refs. 42-43 which primarily discuss monolayer and bulk MoS₂.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Phonon scattering mechanisms in WTe$_2$ observed by ultrafast coherent phonon spectroscopy." pith.science (2026). https://pith.science/paper/C3BNVOJ6

@misc{pith2026260707087,
  author       = {Pith},
  title        = {Pith review of: Phonon scattering mechanisms in WTe$_2$ observed by ultrafast coherent phonon spectroscopy},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/C3BNVOJ6}},
  note         = {Machine review of arXiv:2607.07087}
}
abstract

Revealing the mechanisms of phonon scattering is crucial for understanding material properties such as transport characteristics and optical responses. It can be discussed by measuring the temperature dependence of the phonon energy and lifetime. To gain insight into these mechanisms in Weyl semimetal T$_d$-WTe$_2$, we investigated coherent phonons using time-resolved pump-probe spectroscopy in a wide temperature range from 4.6 to 300 K. The temperature dependence of the frequency and decay rate of the two high-frequency optical modes was described by the conventional anharmonic phonon-phonon scattering model. In contrast, the low-frequency mode at 2.4 THz exhibited anomalous behavior, which can be interpreted as the contribution of phonon-electron scattering.

Figures

Figures reproduced from arXiv: 2607.07087 by the authors.

Figure 1
Figure 1. FIG. 1. (a) The time-domain coherent phonon signal obtained [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. FIG. 2. (a) The coherent phonon signals of [PITH_FULL_IMAGE:figures/full_fig_p003_2.png] view at source ↗
Figure 4
Figure 4. FIG. 4. Schematic illustration of the interband transition [PITH_FULL_IMAGE:figures/full_fig_p005_4.png] view at source ↗

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

47 extracted references · 47 canonical work pages

  1. [1]

    01 THz, ω 6 = 4

    95 THz, ω 5 = 4 . 01 THz, ω 6 = 4 . 90 THz, and ω 7 =

  2. [2]

    According to previous studies on Raman spec- troscopy, all of these vibrational modes correspond to the A1 optical phonon mode [12–15]

    31 THz. According to previous studies on Raman spec- troscopy, all of these vibrational modes correspond to the A1 optical phonon mode [12–15]. In particular, ω 1 is an interlayer shear mode, while ω 2 ∼ ω 7 are intralayer op- tical phonon modes. These results are consistent with previous studies on coherent phonon spectroscopy [16– 18]. The FT peaks belo...

  3. [3]

    !!! "! ! ! !

    00000896. The fraction of each process obtained indi- cate that a contribution of the four-phonon process plays a minor role of ∼ 10%. One possible reason for the inclu- sion of the four-phonon process is that ω 7 (∼ 6.3 THz) has relatively high energy. Based on phonon dispersion, it would be difficult to distribute its energy only through a three-phonon pr...

  4. [4]

    J. Xiao, Y. Wang, H. Wang, C. Pemmaraju, S. Wang, P. Muscher, E. J. Sie, C. M. Nyby, T. P. Devereaux, X. Qian, et al., Berry curvature memory through elec- trically driven stacking transitions, Nat. Phys. 16, 1028 (2020)

  5. [5]

    A. A. Soluyanov, D. Gresch, Z. Wang, Q. Wu, M. Troyer, X. Dai, and B. A. Bernevig, Type-II Weyl semimetals, Nature 527, 495 (2015)

  6. [6]

    M. N. Ali, J. Xiong, S. Flynn, J. Tao, Q. D. Gib- son, L. M. Schoop, T. Liang, N. Haldolaarachchige, M. Hirschberger, N. P. Ong, et al., Large, non-saturating magnetoresistance in WTe 2, Nature 514, 205 (2014)

  7. [7]

    Thoutam, Y

    L. Thoutam, Y. Wang, Z. Xiao, S. Das, A. Luican-Mayer, R. Divan, G. Crabtree, and W. Kwok, Temperature- dependent three-dimensional anisotropy of the magne- toresistance in WTe 2, Phys. Rev. Lett. 115, 046602 (2015)

  8. [8]

    Y. Wu, N. H. Jo, M. Ochi, L. Huang, D. Mou, S. L. Bud’ko, P. Canfield, N. Trivedi, R. Arita, and A. Kamin- ski, Temperature-induced Lifshitz transition in WTe 2, Phys. Rev. Lett. 115, 166602 (2015)

Show all 47 references
  1. [9]

    Zhang, Z

    Q. Zhang, Z. Liu, Y. Sun, H. Yang, J. Jiang, S.-K. Mo, Z. Hussain, X. Qian, L. Fu, S. Yao, et al., Lifshitz transi- tions induced by temperature and surface doping in type- II Weyl semimetal candidate T d-WTe2, physica status solidi (RRL)–Rapid Research Letters 11, 1700209 (2017)

  2. [10]

    X.-C. Pan, X. Chen, H. Liu, Y. Feng, Z. Wei, Y. Zhou, Z. Chi, L. Pi, F. Yen, F. Song, et al., Pressure-driven dome-shaped superconductivity and electronic structural evolution in tungsten ditelluride, Nat. Commun. 6, 7805 (2015). 7

  3. [11]

    E. J. Sie, C. M. Nyby, C. Pemmaraju, S. J. Park, X. Shen, J. Yang, M. C. Hoffmann, B. Ofori-Okai, R. Li, A. H. Reid, et al., An ultrafast symmetry switch in a Weyl semimetal, Nature 565, 61 (2019)

  4. [12]

    M. Akei, T. Fukuda, Y. Mizukoshi, K. Kikuchi, and M. Hase, Role of interlayer shear phonons on lattice sym- metry switching in the transition metal dichalcogenide WTe2, Phys. Rev. B 112, L140101 (2025)

  5. [13]

    Y. Dai, J. Bowlan, H. Li, H. Miao, S. Wu, W. Kong, P. Richard, Y. Shi, S. A. Trugman, J.-X. Zhu, et al., Ultrafast carrier dynamics in the large-magnetoresistanc e material WTe 2, Phys. Rev. B 92, 161104 (2015)

  6. [14]

    Lifshitz et al., Anomalies of electron characteristics of a metal in the high pressure region, Sov

    I. Lifshitz et al., Anomalies of electron characteristics of a metal in the high pressure region, Sov. Phys. JETP 11, 1130 (1960)

  7. [15]

    Kong, S.-F

    W.-D. Kong, S.-F. Wu, P. Richard, C.-S. Lian, J.-T. Wang, C.-L. Yang, Y.-G. Shi, and H. Ding, Raman scat- tering investigation of large positive magnetoresistance material WTe 2, Appl. Phys. Lett. 106 (2015)

  8. [16]

    X. Ma, P. Guo, C. Yi, Q. Yu, A. Zhang, J. Ji, Y. Tian, F. Jin, Y. Wang, K. Liu, et al., Raman scattering in the transition-metal dichalcogenides of 1T ′-MoTe2, T d- MoTe2, and T d-WTe2, Phys. Rev. B 94, 214105 (2016)

  9. [17]

    Jiang, J

    Y. Jiang, J. Gao, and L. Wang, Raman fingerprint for semi-metal WTe 2 evolving from bulk to monolayer, Sci. Rep. 6, 19624 (2016)

  10. [18]

    Q. Song, X. Pan, H. Wang, K. Zhang, Q. Tan, P. Li, Y. Wan, Y. Wang, X. Xu, M. Lin, et al., The in-plane anisotropy of WTe 2 investigated by angle-dependent and polarized raman spectroscopy, Sci. Rep. 6, 29254 (2016)

  11. [19]

    Soranzio, M

    D. Soranzio, M. Savoini, P. Beaud, F. Cilento, L. Boie, J. Dössegger, V. Ovuka, S. Houver, M. Sander, S. Zer- dane, et al., Strong modulation of carrier effective mass in WTe 2 via coherent lattice manipulation, npj 2D Ma- terials and Applications 6, 71 (2022)

  12. [20]

    P. Hein, S. Jauernik, H. Erk, L. Yang, Y. Qi, Y. Sun, C. Felser, and M. Bauer, Mode-resolved reciprocal space mapping of electron-phonon interaction in the Weyl semimetal candidate T d-WTe2, Nat. Commun. 11, 2613 (2020)

  13. [21]

    Drueke, J

    E. Drueke, J. Yang, and L. Zhao, Observation of strong and anisotropic nonlinear optical effects through polarization-resolved optical spectroscopy in the type-I I Weyl semimetal T d-WTe2, Phys. Rev. B 104, 064304 (2021)

  14. [22]

    B. He, C. Zhang, W. Zhu, Y. Li, S. Liu, X. Zhu, X. Wu, X. Wang, H.-h. Wen, and M. Xiao, Coherent optical phonon oscillation and possible electronic softening in WTe2 crystals, Sci. Rep. 6, 30487 (2016)

  15. [23]

    Klemens, Anharmonic decay of optical phonons, Phys

    P. Klemens, Anharmonic decay of optical phonons, Phys. Rev. 148, 845 (1966)

  16. [24]

    M. Hase, K. Ushida, and M. Kitajima, Anharmonic decay of coherent optical phonons in antimony, J. Phys. Soc. Jpn 84, 024708 (2015)

  17. [25]

    Balkanski, R

    M. Balkanski, R. Wallis, and E. Haro, Anharmonic effects in light scattering due to optical phonons in silicon, Phys. Rev. B 28, 1928 (1983)

  18. [26]

    S. Cao, F. Jin, J. Zhao, Y.-Z. Long, J. Luo, Q. Zhang, and Z.-G. Chen, Enhanced phonon–phonon interactions and weakened electron-phonon coupling in charge den- sity wave topological semimetal EuAl 4 with a possible intermediate electronic state, J. Phys. Chem. Lett. 16, 1909 (2025)

  19. [27]

    Y. Tao, J. A. Schneeloch, A. A. Aczel, and D. Louca, Td to 1T ′ structural phase transition in the WTe 2 Weyl semimetal, Phys. Rev. B 102, 060103 (2020)

  20. [28]

    J. Yu, J. Zhao, Y. Lv, Y. Han, Z. Hang, J. Xu, and J. Hu, Anomalous nonequilibrium phonon scattering in the Weyl semimetal WP 2, Phys. Rev. Research 5, 023137 (2023)

  21. [29]

    G. B. Osterhoudt, Y. Wang, C. A. Garcia, V. M. Plisson, J. Gooth, C. Felser, P. Narang, and K. S. Burch, Evi- dence for dominant phonon-electron scattering in Weyl semimetal WP 2, Phys. Rev. X 11, 011017 (2021)

  22. [30]

    Coulter, G

    J. Coulter, G. B. Osterhoudt, C. A. Garcia, Y. Wang, V. M. Plisson, B. Shen, N. Ni, K. S. Burch, and P. Narang, Uncovering electron-phonon scattering and phonon dynamics in type-I Weyl semimetals, Phys. Rev. B 100, 220301 (2019)

  23. [31]

    H.-Y. Yang, X. Yao, V. Plisson, S. Mozaffari, J. P. Scheifers, A. F. Savvidou, E. S. Choi, G. T. McCand- less, M. F. Padlewski, C. Putzke, et al., Evidence of a coupled electron-phonon liquid in NbGe 2, Nat. Commun. 12, 5292 (2021)

  24. [32]

    Bonini, M

    N. Bonini, M. Lazzeri, N. Marzari, and F. Mauri, Phonon anharmonicities in graphite and graphene, Phys. Rev. Lett. 99, 176802 (2007)

  25. [33]

    Piscanec, M

    S. Piscanec, M. Lazzeri, F. Mauri, A. Ferrari, and J. Robertson, Kohn anomalies and electron-phonon inter- actions in graphite, Phys. Rev. Lett. 93, 185503 (2004)

  26. [34]

    Kohn and L

    W. Kohn and L. J. Sham, Self-consistent equations in- cluding exchange and correlation effects, Phys. Rev. 140, A1133 (1965)

  27. [35]

    Y. Hou, L. Li, S. Sun, G. Liu, H. Zhao, Z. Chen, X. Yan, Y.-Y. Lv, Y. Yang, S.-H. Yao, et al., Probing anisotropic quasiparticle dynamics and topological phase transitions in quasi-1D topological insulator ZrTe 5, Advanced Sci- ence 12, e04798 (2025)

  28. [36]

    J. E. Callanan, G. Hope, R. D. Weir, and E. F. Westrum, Thermodynamic properties of tungsten ditel- luride (WTe 2) I. the preparation and lowtemperature heat capacity at temperatures from 6 K to 326 K, J. Chem. Thermodynamics 24, 627 (1992)

  29. [37]

    Zhang, C

    Y. Zhang, C. Wang, L. Yu, G. Liu, A. Liang, J. Huang, S. Nie, X. Sun, Y. Zhang, B. Shen, et al., Electronic evidence of temperature-induced Lifshitz transition and topological nature in ZrTe 5, Nat. Commun. 8, 15512 (2017)

  30. [38]

    Zhang, C

    Y. Zhang, C. Wang, G. Liu, A. Liang, L. Zhao, J. Huang, Q. Gao, B. Shen, J. Liu, C. Hu, et al., Temperature- induced Lifshitz transition in topological insulator can- didate HfTe 5, Science bulletin 62, 950 (2017)

  31. [39]

    Cheng, F

    L. Cheng, F. Fei, H. Hu, Y. Dai, F. Song, and J. Qi, Ultra- fast carrier and lattice dynamics in the Dirac semimetal NiTe2, Phys. Rev. B 106, 104308 (2022)

  32. [40]

    Beaulieu, S

    S. Beaulieu, S. Dong, N. Tancogne-Dejean, M. Dendzik, T. Pincelli, J. Maklar, R. P. Xian, M. A. Sentef, M. Wolf, A. Rubio, et al., Ultrafast dynamical Lifshitz transition, Sci. Adv. 7, eabd9275 (2021)

  33. [41]

    S. Lu, Y. Zhang, J. Li, Y. Deng, X. Li, Q. Gong, and Y. Liu, Probing Lifshitz shift and topological phase tran- sition of MoTe 2 with photoemission in momentum and real space, J. Phys. Chem. C 129, 18141 (2025)

  34. [42]

    Sruthi, D

    S. Sruthi, D. S. Narang, P. Vishnubhotla, A. Bera, S. Kalimuddin, K. Watanabe, T. Taniguchi, M. Mon- dal, and A. Bid, Interband scattering across the Lifshitz transition in WTe 2, Phys. Rev. B 106, 115421 (2022). 8

  35. [43]

    M. Luo, Z. Zhi, A. Liu, S. Liu, S. Jiao, Q. Kang, and R. Xie, Nonlinear infrared photocurrent driven by Lif- shitz transition, Infrared Physics & Technology 152, 106244 (2026)

  36. [44]

    M. Hase, M. Kitajima, S.-i. Nakashima, and K. Mi- zoguchi, Dynamics of coherent anharmonic phonons in bismuth using high density photoexcitation, Phys. Rev. Lett. 88, 067401 (2002)

  37. [45]

    Sohier, M

    T. Sohier, M. Calandra, and F. Mauri, Two-dimensional fröhlich interaction in transition-metal dichalcogenide monolayers: Theoretical modeling and first-principles calculations, Phys. Rev. B 94, 085415 (2016)

  38. [46]

    Pan, P.-N

    Y. Pan, P.-N. Hildebrandt, D. Zahn, M. Zacharias, Y. W. Windsor, R. Ernstorfer, F. Caruso, and H. Seiler, Momentum-resolved signatures of carrier screening ef- fects on electron–phonon coupling in MoS 2, ACS nano 19, 11381 (2025)

  39. [47]

    Harter, D

    J. Harter, D. Kennes, H. Chu, A. De La Torre, Z. Zhao, J.-Q. Yan, D. Mandrus, A. Millis, and D. Hsieh, Evidence of an improper displacive phase transition in Cd 2Re2O7 via time-resolved coherent phonon spectroscopy, Phys. Rev. Lett. 120, 047601 (2018)

Pith tools

Reviewed July 9, 2026 · model on record in the stance chip above.