Pith. sign in

REVIEW 3 major objections 5 minor 102 references

Electron-Phonon Functional Renormalization Group of Fermi Liquid Instabilities

T0 review · 3 major / 5 minor · reviewed 2026-07-10 · grok-4.5

Pith's one-line read A single FRG flow of the electronic vertex treats phonon- and electron-driven Fermi-liquid instabilities on equal footing, recovering Peierls charge-bond order and its competition with magnetism and superconductivity.

desk verdict Clean, usable FRG that folds dispersive acoustic phonons into the static electronic vertex and recovers Peierls CBOs competing with AFM and s/d-wave SC; the frozen-retarded-vertex choice is the only real soft spot and is already standard. read the letter →

arxiv 2607.07804 v1 pith:YJH4NIHF submitted 2026-07-08 cond-mat.str-el cond-mat.mtrl-scicond-mat.supr-con

classification cond-mat.str-elcond-mat.mtrl-scicond-mat.supr-con PACS 71.10.Fd71.38.-k74.20.Mn71.45.Lr
keywords functionalrenormalizationgroupelectron-phononcouplingPeierlstransitioncharge-bondorderFermi-liquidinstabilitiesHubbardmodelacousticphononstruncated-unityFRG
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 sets out a practical way to put electron-electron repulsion and electron-phonon coupling inside one renormalization-group calculation. Phonons are integrated out once, leaving a retarded density-density interaction that is then fed into the usual all-electronic functional renormalization group for the two-particle vertex. Because every diagrammatic channel is kept, charge-bond order, antiferromagnetism, nematic Pomeranchuk order and both s- and d-wave pairing compete on the same footing. On the square-lattice Hubbard model with acoustic phonons the method recovers the expected Peierls charge-bond orders (and shows they are equivalent to phonon softening), then maps how those orders give way to magnetic and superconducting states once a Hubbard U is turned on or the system is doped. The calculation is designed so that realistic ab-initio band structures and phonon dispersions can be dropped in without changing the numerical cost of ordinary static FRG. A sympathetic reader therefore obtains a single, unbiased tool for deciding which electronic order wins when lattice and correlation effects are intertwined.

What carries the argument

The phonon-mediated retarded interaction V (Eq. 20) projected into the static FRG channels according to Eqs. 29–31, so that the same vertex flow simultaneously generates charge-bond, spin and pairing instabilities.

What would settle it

A frequency-dependent FRG or determinant quantum Monte Carlo calculation on the same square-lattice acoustic model that finds a different leading instability or a substantially shifted critical scale for the same (U,λ,α²) parameters.

Watch

Extended reading notes

Core claim

Integrating out dispersive phonons produces a retarded electron-electron interaction that can be inserted into a static truncated-unity FRG flow of the two-particle vertex; the resulting channel-decomposed flow treats phonon-mediated charge-bond order and purely electronic instabilities on equal footing and, for the square-lattice Hubbard model with acoustic phonons, yields Peierls-type transitions whose competition with AFM and s/d-wave superconductivity is fully mapped.

Load-bearing premise

The phonon-induced retarded piece of the interaction is frozen and never itself renormalized during the flow; if frequency-dependent corrections to the electron-phonon coupling grow large, the phase boundaries can shift.

Editorial extensions

If this is right

  • Peierls charge-bond order and phonon softening become two descriptions of one and the same transition inside a single electronic calculation.
  • Competition between conventional s-wave and unconventional d-wave pairing can be read off directly from the same FRG flow once both U and electron-phonon coupling are present.
  • Ab-initio electronic and phononic Hamiltonians can be fed into the existing static FRG pipeline without extra numerical cost, enabling material-specific phase diagrams for intertwined lattice and correlation instabilities.
  • Cross-channel vertex corrections lift artificial degeneracies (such as the O(4) AFM/sSC/CDW manifold) and generate mixed CDW+CBO order parameters that pure RPA cannot produce.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • The same static-flow construction immediately extends to optical phonons, multi-orbital models and systems with spin-orbit coupling, giving a uniform route to electron-phonon problems that currently require separate Eliashberg or DFPT treatments.
  • Because the method already interfaces to existing ab-initio codes, the first concrete applications are likely to be materials in which DFPT already predicts soft modes while electronic correlations are known to be strong (kagome metals, nickelates, twisted graphene).
  • Holding the retarded interaction fixed is the price paid for numerical scalability; a controlled test that re-introduces selected frequency dependence only in the softest phonon modes would quantify how much the present phase boundaries move.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

3 major / 5 minor

Summary. The manuscript formulates a functional renormalization-group (FRG) scheme for lattice fermions that incorporates both electronic interactions and electron-phonon coupling (EPC) from dispersive phonon bands. Phonons are integrated out to produce a retarded density-density interaction that is inserted into the static truncated-unity FRG flow of the electronic two-particle vertex, with channel-dependent frequency projections that retain retardation effects (Eqs. 20, 29–31). The approach is illustrated on the square-lattice Hubbard model coupled to acoustic phonons, where pure D-channel FRG is shown to be equivalent to leading-order phonon softening (Eqs. 39–43), and full multi-channel FRG yields phase diagrams of Peierls-type charge-bond order competing with antiferromagnetism, d-wave Pomeranchuk order, and s-/d-wave superconductivity as functions of EPC strength, phonon anisotropy, Hubbard U and doping.

Significance. If the approximations hold, the work supplies a computationally practical, channel-unbiased framework that places phonon- and electron-mediated Fermi-liquid instabilities on equal footing and is already interfaced to existing ab-initio FRG codes. The analytic and numerical demonstration that D-channel FRG recovers the RPA phonon self-energy, together with the explicit (λ,α²) and (U,λ) phase diagrams, constitutes a concrete advance over earlier Holstein or SSH treatments limited to local or optical modes. The method’s scalability to multi-orbital, multi-phonon ab-initio Hamiltonians is a genuine strength for materials such as kagome metals and nickelates where charge, spin and lattice orders intertwine.

major comments (3)
  1. [Section III C] Section III C states that the retarded phonon-mediated vertex V_R is held fixed throughout the flow and is never renormalized. This is the central technical approximation that enables computational equivalence to static TUFRG. While the authors cite a full-frequency Hubbard–Holstein study [56] in support, that model has momentum-independent optical phonons; for the acoustic, dispersive, momentum-dependent EPC of the present work the frequency structure of vertex corrections differs. A quantitative estimate (or a limited frequency-dependent check) of the error incurred by freezing V_R is needed before the phase boundaries in Figs. 6 and 8 can be regarded as robust.
  2. [Section III A, Fig. 2] Section III A and Fig. 2 introduce a finite lifetime regulator δ=10^{-7} that forces V(q=0,ω_n=0)=0 in order to remove the directional discontinuity of acoustic phonons. The d-wave Pomeranchuk instability reported in the large-α² FRG phase diagram is an asymptotic q→0 order. The manuscript does not demonstrate that the location or critical scale of this instability is stable under variation of δ (or under a soft infrared cutoff). Such a check is required to confirm that the dPom phase is physical rather than an artifact of the regulator.
  3. [Section III F, Fig. 8] The equivalence between phonon softening and electronic D-RPA is established rigorously only for U=0 (Section III F and Fig. 5). Once a finite Hubbard U is present, the full multi-channel FRG generates additional self-energy and vertex corrections that have no direct counterpart in the phonon Dyson equation used in DFPT. The manuscript should clarify to what extent the “phononic picture” remains valid in the (U,λ) diagrams of Fig. 8, or explicitly restrict the phonon-softening interpretation to the U=0 sector.
minor comments (5)
  1. [Throughout] Several section headings contain spurious spaces (“F unctional Renormalization”, “T runcated Unity FRG”, “RESUL TS”, “SUMMAR Y & OUTLOOK”), presumably from PDF extraction; these should be corrected for the final version.
  2. [Section I] In the Introduction the phrase “charge-bond order from the electronic picture condify the same transition” appears to be a typographical error for “codify” or “confirm”.
  3. [Fig. 1] Figure 1(d) caption refers to “red line thickness corresponding to its strength s(ν)_q”; the definition of s(ν)_q is given only later in Eq. (16). A forward reference would improve readability.
  4. [Eq. (45), Fig. 6] The parameter α² is defined in Eq. (45) as K∥/(K∥+K⊥), yet the phase diagrams of Fig. 6 are plotted versus α² while the text occasionally refers to “α”. Consistent notation would avoid confusion.
  5. [Section V] The outlook lists eight material platforms; a brief remark on which of them already possess publicly available cDFPT or EPC matrix elements would help readers assess immediate applicability.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: phase diagrams and D-channel/phonon-softening equivalence are derived from the microscopic Hamiltonian and diagrammatic identities, not forced by fits or self-referential definitions.

full rationale

The paper constructs an all-electronic FRG by integrating out non-interacting phonons to a retarded density-density vertex (Eq. 20), freezes that retarded piece along the flow (explicit approximation in Sec. III C, justified by comparison to a full-frequency Hubbard-Holstein study), and solves the static TUFRG equations for a square-lattice Hubbard model plus acoustic phonons whose parameters (U, λ, α^{2}, ω) are scanned rather than fitted. The claimed equivalence between phonon softening (Eq. 39) and D-RPA (Eq. 42) is an algebraic identity obtained by solving the restricted flow equation and rewriting it in phonon-propagator language; it is not a prediction that re-uses its own input. Self-citations point only to the authors’ TUFRG library (divERGe) and prior electronic FRG infrastructure; they supply numerical backend, not a uniqueness theorem or load-bearing premise. No step reduces a claimed result to a definition, a fit, or an unverified self-citation chain. The derivation is therefore self-contained against the microscopic model it starts from.

Assumptions & free parameters 5 free parameters · 5 assumptions · 0 invented entities

The central claim rests on standard many-body and FRG machinery plus a small set of modeling and truncation choices that are stated but not independently validated for acoustic phonons. No new particles or forces are invented; free parameters are ordinary model couplings that are scanned rather than fitted to experiment.

free parameters (5)
  • λ (dimensionless EPC strength)
    Scanned over 0–0.4 to produce phase diagrams; defined as g²/(W M ω²). Controls the overall scale of phonon-mediated attraction.
  • α² = K∥/(K∥+K⊥)
    Ratio of spring constants that tunes the relative bare phonon frequencies at X versus M; scanned to select X-type versus M-type bond order.
  • ω (characteristic phonon frequency scale)
    Sets the retardation scale relative to the electronic bandwidth; held at 0.1t in most diagrams and varied in Fig. 7.
  • U (Hubbard repulsion)
    Scanned versus λ in Fig. 8; standard onsite Coulomb strength.
  • δ = 10^{-7} (phonon lifetime regulator)
    Ad-hoc infinitesimal used to remove the q=0 discontinuity of acoustic-phonon-mediated vertices; numerical choice that forces V(q=0,ω=0)=0.
assumptions (5)
  • domain assumption Phonons are non-interacting (harmonic approximation); only bilinear electron-phonon coupling is retained.
    Stated in Sec. II; standard but excludes anharmonic and multi-phonon processes that can matter near structural transitions.
  • ad hoc to paper The retarded phonon-mediated vertex is not renormalized along the FRG flow; only the static electronic vertex flows.
    Explicit approximation in Sec. III C chosen for numerical tractability and ab-initio scalability.
  • domain assumption Static (zero external frequency) projection of the FRG vertex is sufficient to identify the leading instability.
    Standard in electronic FRG; partially supported by a cited full-frequency Holstein study, but not re-validated here for acoustic phonons.
  • domain assumption Truncated-unity form-factor expansion of fermionic bilinears captures the relevant real-space structure of the order parameters.
    Inherited from the TUFRG literature and the divERGe library; accuracy depends on form-factor cutoff (not quantified in the paper).
  • domain assumption Sharp multiplicative frequency cutoff is an adequate RG regulator.
    Used to obtain the loop derivatives in Eq. (26); common but known to introduce cutoff artifacts.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Electron-Phonon Functional Renormalization Group of Fermi Liquid Instabilities." pith.science (2026). https://pith.science/paper/YJH4NIHF

@misc{pith2026260707804,
  author       = {Pith},
  title        = {Pith review of: Electron-Phonon Functional Renormalization Group of Fermi Liquid Instabilities},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/YJH4NIHF}},
  note         = {Machine review of arXiv:2607.07804}
}
read the original abstract

We formulate a functional renormalization group (FRG) ansatz for correlated electron models that incorporates electronic interactions as well as electron-phonon coupling (EPC) stemming from dispersive phonon bands. Particularizing to the RG flow of the electron-electron interaction vertex, we treat phonon- and electron-mediated Fermi liquid instabilities on equal footing as we analyze tentative electronic order parameters related to charge, spin, nematicity, and superconducting pairing. We illustrate the approach at the example of Peierls-type transitions we find for the Hubbard model on the square lattice coupled to acoustic phonon bands. Our method allows to incorporate full electronic and phononic ab initio input, and thus lends itself to the analysis of electronic order from intertwined electronic interactions and EPC at a microscopically most substantiated level.

Figures

Figures reproduced from arXiv: 2607.07804 by the authors.

Figure 1
Figure 1. FIG. 1. The Hubbard model on the square lattice (b) with its band structure (a). We indicate the Fermi level at half filling [PITH_FULL_IMAGE:figures/full_fig_p003_1.png] view at source ↗
Figure 2
Figure 2. FIG. 2. Maximum eigenvalue of the phonon-mediated re [PITH_FULL_IMAGE:figures/full_fig_p004_2.png] view at source ↗
Figure 3
Figure 3. FIG. 3. The flow of the static vertex [PITH_FULL_IMAGE:figures/full_fig_p005_3.png] view at source ↗
Figures from the paper (5 more)
Figure 4
Figure 4. Figure 4: FIG. 4. The lowest order correction to the phonon propagator [PITH_FULL_IMAGE:figures/full_fig_p007_4.png]
Figure 5
Figure 5. Figure 5: FIG. 5. (a,b): Renormalization of the phonon bands accord [PITH_FULL_IMAGE:figures/full_fig_p009_5.png]
Figure 6
Figure 6. Figure 6: FIG. 6. Phase diagram in ( [PITH_FULL_IMAGE:figures/full_fig_p011_6.png]
Figure 7
Figure 7. Figure 7: , where the instantaneous electron-electron inter￾action U acts as the main driver of the AFM instability in the C-channel and teams up with the static part of the electron-phonon interaction. The combined interac￾tion supersedes all retarded electron-phonon driven pro…
Figure 8
Figure 8. Figure 8: FIG. 8. Phase diagram in ( [PITH_FULL_IMAGE:figures/full_fig_p012_8.png]

Discussion (0). Sign in to comment.

Reference graph

Works this paper leans on

102 extracted references · 102 canonical work pages

  1. [56]

    Berges, N

    J. Berges, N. Tetradis, and C. Wetterich, Non- perturbative renormalization flow in quantum field the- ory and statistical physics, Physics Reports Renormal- ization Group Theory in the New Millennium. IV,363, 223 (2002)

  2. [1]

    This fixes the on-site component toC 0 =−2(C ˆx+C ˆy) and the resulting dynamical matrix, M Dq = 2 [cos(qx)−1]C ˆx+ 2 [cos(qy)−1]C ˆy,(11) has only acoustic modes [cf. Fig. 1(d)]. The eigendecom- position yields one out-of-plane mode and two in-plane modes M ω2 z =−2K z [cos(qx) + cos(qy)−2], M ω2 x/y =−2K ∥ cos(qx/y)−1 −2K ⊥ cos(qy/x)−1 , (12) with trivi...

  3. [2]

    (39) by successively lowering the temperature of the system and inspecting the momentum at which the phonon dispersion first becomes imaginary

    Bond orders in the phononic picture ForU= 0, we can obtain the lattice instability from Eq. (39) by successively lowering the temperature of the system and inspecting the momentum at which the phonon dispersion first becomes imaginary. The precise shape of the structural instability can be deduced from the associated phonon mode. Applying this to the mode...

  4. [3]

    Electronic perspective: D-RPA As established in Section III F, the renormalization of the phonon self-energy is formally equivalent with an FRG treatment of the phonon-mediated effective 9 Γ X M Γ −0.4 −0.2 0.0 0.2 0.4 0.6 0.8 1.0 ω2(T ) Γ X M Γ 0 π 2 π qx 0 π 2 πqy 0 π 2 π qx 100 101 102 kBT 0.0 0.5 1.0 λrel max(q) (a) (b) (c) (d) α2 = 0.8 α2 = 0.9 (e) (...

  5. [4]

    Charge orders When turning on thePandC-channels in the FRG and allowing for cross channel projections, the general structure of theD-RPA phase diagram is maintained: TheX-type CBO phase, that is primarily governed by the bare vertex due to large Λ c, persists and is only pushed to lowerα 2 values, since the FRG incorporates more screening effects generica...

  6. [5]

    We hence add an onsite repulsionUaccording to Eq

    Competition with electronic interactions Unlike in most other numerical methods, the inclu- sion of finite Coulomb repulsion in combination with the electron-phonon coupling as well as doping is straightfor- ward in FRG as outlined in Section III. We hence add an onsite repulsionUaccording to Eq. (2) to the electron- phonon coupling Eq. (4) and investigat...

  7. [6]

    Born and R

    M. Born and R. Oppenheimer, Zur Quantentheorie der Molekeln, Annalen der Physik389, 457 (1927)

  8. [7]

    Kohn, Image of the fermi surface in the vibration spectrum of a metal, Phys

    W. Kohn, Image of the fermi surface in the vibration spectrum of a metal, Phys. Rev. Lett.2, 393 (1959)

Show all 102 references
  1. [8]

    H. A. Jahn and E. Teller, Stability of polyatomic molecules in degenerate electronic states - I–orbital de- generacy, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences161, 220 (1937)

  2. [9]

    M. D. Johannes and I. I. Mazin, Fermi surface nesting and the origin of charge density waves in metals, Phys. Rev. B77, 165135 (2008)

  3. [10]

    Jiang, J.-X

    Y.-X. Jiang, J.-X. Yin, M. M. Denner, N. Shumiya, B. R. Ortiz, G. Xu, Z. Guguchia, J. He, M. S. Hossain, X. Liu, J. Ruff, L. Kautzsch, S. S. Zhang, G. Chang, I. Belopol- ski, Q. Zhang, T. A. Cochran, D. Multer, M. Litskevich, Z.-J. Cheng, X. P. Yang, Z. Wang, R. Thomale, T. Ne...

  4. [11]

    H. Zhao, H. Li, B. R. Ortiz, S. M. L. Teicher, T. Park, M. Ye, Z. Wang, L. Balents, S. D. Wilson, and I. Zeljkovic, Cascade of correlated electron states in the kagome superconductor csv3sb5, Nature599, 216 (2021)

  5. [12]

    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, P. Dai, Q. Si, H. Miao, R. Thomale, T. Neupert, Y. Shi, R. Khasanov, M. Z. Hasan, H. Luetkens, and Z. Guguchia, Time-reversal symmetry-breaking charge order in a kagome superc...

  6. [13]

    Di Sante, T

    D. Di Sante, T. Neupert, G. Sangiovanni, R. Thomale, R. Comin, J. G. Checkelsky, I. Zeljkovic, and S. D. Wil- son, Kagome metals, Rev. Mod. Phys.98, 015002 (2026)

  7. [14]

    M. L. Kiesel, C. Platt, and R. Thomale, Unconventional fermi surface instabilities in the kagome hubbard model, Phys. Rev. Lett.110, 126405 (2013)

  8. [15]

    Neupert, M

    T. Neupert, M. M. Denner, J.-X. Yin, R. Thomale, and M. Z. Hasan, Charge order and superconductivity in kagome materials, Nature Physics18, 137 (2022)

  9. [16]

    L. Huai, Z. Wang, H. Rao, Y. Han, B. Liu, S. Yu, Y. Zhang, R. Zang, R. Luan, S. Peng, Z. Qiao, Z. Wang, J. He, T. Wu, and X. Chen, Electron-correlation-assisted charge stripe order in a kagome superconductor, Phys. Rev. X15, 041039 (2025)

  10. [17]

    Wang, Y.-X

    Z. Wang, Y.-X. Jiang, J.-X. Yin, Y. Li, G.-Y. Wang, H.-L. Huang, S. Shao, J. Liu, P. Zhu, N. Shumiya, M. S. Hossain, H. Liu, Y. Shi, J. Duan, X. Li, G. Chang, P. Dai, Z. Ye, G. Xu, Y. Wang, H. Zheng, J. Jia, M. Z. Hasan, and Y. Yao, Electronic nature of chiral charge order in ...

  11. [18]

    J. Zhan, H. Hohmann, M. D¨ urrnagel, R. Fu, S. Zhou, Z. Wang, R. Thomale, X. Wu, and J. Hu, Loop current order on the kagome lattice, arXiv:2506.01648 (2025)

  12. [19]

    Y. Chen, W. Qin, S. Zhang, P. Cui, Q. Niu, and Z. Zhang, Emergence of chiral phonons in two-dimensional kagome lattices harboring electronic chirality, Phys. Rev. Lett. 135, 126608 (2025)

  13. [20]

    D. M. Juraschek and N. A. Spaldin, Orbital magnetic mo- ments of phonons, Phys. Rev. Mater.3, 064405 (2019)

  14. [21]

    J. Luo, T. Lin, J. Zhang, X. Chen, E. R. Blackert, R. Xu, B. I. Yakobson, and H. Zhu, Large effective magnetic fields from chiral phonons in rare-earth halides, Science 382, 698 (2023)

  15. [22]

    Tonacatl-Monez, R

    R.-A. Tonacatl-Monez, R. Heid, and O. De la Pe˜ na- Seaman, Correlation between magnetism and lattice dy- namics for cubic fege under pressure, Journal of Physics: Condensed Matter37, 465801 (2025)

  16. [23]

    Liu, Z.-Y

    Y. Liu, Z.-Y. Liu, J.-K. Bao, P.-T. Yang, L.-W. Ji, S.- Q. Wu, Q.-X. Shen, J. Luo, J. Yang, J.-Y. Liu, C.-C. Xu, W.-Z. Yang, W.-L. Chai, J.-Y. Lu, C.-C. Liu, B.-S. Wang, H. Jiang, Q. Tao, Z. Ren, X.-F. Xu, C. Cao, Z.-A. Xu, R. Zhou, J.-G. Cheng, and G.-H. Cao, Superconduc- tiv...

  17. [24]

    L. Liu, Y. Li, H. Tan, Y. Liu, K. Sun, Y. Shi, Y. Zhai, H. Lin, G. Cao, B. Yan, X. Chen, T. Wu, G.-M. Zhang, and L. Yang, Unraveling intertwined orders in the strongly correlated kagome metal cscr3sb5, National Science Review , nwag044 (2026). 14

  18. [25]

    Zhang, D

    J. Zhang, D. Phelan, A. S. Botana, Y.-S. Chen, H. Zheng, M. Krogstad, S. G. Wang, Y. Qiu, J. A. Rodriguez- Rivera, R. Osborn, S. Rosenkranz, M. R. Norman, and J. F. Mitchell, Intertwined density waves in a metallic nickelate, Nature Communications11, 6003 (2020)

  19. [26]

    Khasanov, V

    R. Khasanov, V. Sazgari, I. Plokhikh, M. Medarde, E. Pomjakushina, T. Klimczuk, S. Kr´ olak, M. J. Winiarski, T. J. Hicken, H. Luetkens, Z. Guguchia, and D. J. Gawryluk, Oxygen-isotope effect on the density wave transitions in la3ni2o7 and la4ni3o10 (2025)

  20. [27]

    G. M. Eliashberg, Interactions between electrons and lat- tice vibrations in a superconductor, Sov. Phys. - JETP (Engl. Transl.); (United States)11:3(1960)

  21. [28]

    Marsiglio, Pairing and charge-density-wave correla- tions in the holstein model at half-filling, Phys

    F. Marsiglio, Pairing and charge-density-wave correla- tions in the holstein model at half-filling, Phys. Rev. B 42, 2416 (1990)

  22. [29]

    Marsiglio, Eliashberg theory: A short review, Annals of Physics Eliashberg Theory at 60: Strong-coupling Su- perconductivity and Beyond,417, 168102 (2020)

    F. Marsiglio, Eliashberg theory: A short review, Annals of Physics Eliashberg Theory at 60: Strong-coupling Su- perconductivity and Beyond,417, 168102 (2020)

  23. [30]

    R. T. Scalettar, N. E. Bickers, and D. J. Scalapino, Com- petition of pairing and peierls–charge-density-wave cor- relations in a two-dimensional electron-phonon model, Phys. Rev. B40, 197 (1989)

  24. [31]

    R. M. Noack, D. J. Scalapino, and R. T. Scalettar, Charge-density-wave and pairing susceptibilities in a two- dimensional electron-phonon model, Phys. Rev. Lett.66, 778 (1991)

  25. [32]

    Sengupta, A

    P. Sengupta, A. W. Sandvik, and D. K. Campbell, Peierls transition in the presence of finite-frequency phonons in the one-dimensional extended peierls-hubbard model at half-filling, Phys. Rev. B67, 245103 (2003)

  26. [33]

    Malkaruge Costa, B

    S. Malkaruge Costa, B. Cohen-Stead, A. T. Ly, J. Neuhaus, and S. Johnston, Comparative determinant quantum monte carlo study of the acoustic and optical variants of the su-schrieffer-heeger model, Phys. Rev. B 108, 165138 (2023)

  27. [34]

    C. Feng, B. Xing, D. Poletti, R. Scalettar, and G. Batrouni, Phase diagram of the su-schrieffer-heeger- hubbard model on a square lattice, Phys. Rev. B106, L081114 (2022)

  28. [35]

    F. F. Assaad and T. C. Lang, Diagrammatic determinan- tal quantum monte carlo methods: Projective schemes and applications to the hubbard-holstein model, Phys. Rev. B76, 035116 (2007)

  29. [36]

    Esterlis, B

    I. Esterlis, B. Nosarzewski, E. W. Huang, B. Moritz, T. P. Devereaux, D. J. Scalapino, and S. A. Kivelson, Break- down of the migdal-eliashberg theory: A determinant quantum monte carlo study, Phys. Rev. B97, 140501 (2018)

  30. [37]

    G¨ otz, S

    A. G¨ otz, S. Beyl, M. Hohenadler, and F. F. Assaad, Valence-bond solid to antiferromagnet transition in the two-dimensional su-schrieffer-heeger model by langevin dynamics, Phys. Rev. B105, 085151 (2022)

  31. [38]

    G¨ otz, M

    A. G¨ otz, M. Hohenadler, and F. F. Assaad, Phases and exotic phase transitions of a two-dimensional su- schrieffer-heeger model, Phys. Rev. B109, 195154 (2024)

  32. [39]

    Cohen-Stead, J

    B. Cohen-Stead, J. Neuhaus, K. Barros, T. A. Maier, and S. Johnston, Smoqyelphqmc.jl: An open-source ju- lia package for efficient and scalable quantum monte carlo simulations of electron-phonon coupled models, arXiv:2606.14425 (2026)

  33. [40]

    Werner and A

    P. Werner and A. J. Millis, Efficient dynamical mean field simulation of the holstein-hubbard model, Phys. Rev. Lett.99, 146404 (2007)

  34. [41]

    Jeckelmann and S

    E. Jeckelmann and S. R. White, Density-matrix renormalization-group study of the polaron problem in the holstein model, Phys. Rev. B57, 6376 (1998)

  35. [42]

    Banerjee, J

    D. Banerjee, J. Thomas, A. Nocera, and S. Johnston, Ground-state and spectral properties of the doped one- dimensional optical hubbard-su-schrieffer-heeger model, Phys. Rev. B107, 235113 (2023)

  36. [43]

    Wang, W.-S

    D. Wang, W.-S. Wang, and Q.-H. Wang, Phonon en- hancement of electronic order and negative isotope effect in the Hubbard-Holstein model on a square lattice, Phys. Rev. B92, 195102 (2015)

  37. [44]

    Q.-G. Yang, D. Wang, and Q.-H. Wang, Functional renormalization group study of the two-dimensional Su- Schrieffer-Heeger-Hubbard model, Phys. Rev. B106, 245136 (2022)

  38. [45]

    N. K. Yirga, K.-M. Tam, and D. K. Campbell, Phonon- induced instabilities in correlated electron hamiltonians, Phys. Rev. B107, 235120 (2023)

  39. [46]

    Holstein, Studies of polaron motion: Part i

    T. Holstein, Studies of polaron motion: Part i. the molecular-crystal model, Annals of Physics8, 325 (1959)

  40. [47]

    W. P. Su, J. R. Schrieffer, and A. J. Heeger, Solitons in polyacetylene, Phys. Rev. Lett.42, 1698 (1979)

  41. [48]

    Metzner, M

    W. Metzner, M. Salmhofer, C. Honerkamp, V. Meden, and K. Sch¨ onhammer, Functional renormalization group approach to correlated fermion systems, Rev. Mod. Phys. 84, 299 (2012)

  42. [49]

    Platt, W

    C. Platt, W. Hanke, and R. Thomale, Functional renor- malization group for multi-orbital fermi surface instabil- ities, Advances in Physics62, 453 (2013)

  43. [50]

    Berges, N

    J. Berges, N. Girotto, T. Wehling, N. Marzari, and S. Ponc´ e, Phonon self-energy corrections: To screen, or not to screen, Phys. Rev. X13, 041009 (2023)

  44. [51]

    Schobert, J

    A. Schobert, J. Berges, E. G. C. P. van Loon, M. A. Sentef, S. Brener, M. Rossi, and T. O. Wehling, Ab ini- tio electron-lattice downfolding: Potential energy land- scapes, anharmonicity, and molecular dynamics in charge density wave materials, SciPost Phys.16, 046 (2024)

  45. [52]

    J. B. Profe, D. M. Kennes, and L. Klebl, divERGe imple- ments various Exact Renormalization Group examples, SciPost Phys. Codebases , 26 (2024)

  46. [53]

    J. B. Profe, D. M. Kennes, and L. Klebl, Codebase release 0.5 for divERGe, SciPost Phys. Codebases , 26 (2024)

  47. [54]

    Berges,Many-body instabilities in two-dimensional materials, Ph.D

    J. Berges,Many-body instabilities in two-dimensional materials, Ph.D. thesis, Universit¨ at Bremen (2020)

  48. [55]

    Giustino, M

    F. Giustino, M. L. Cohen, and S. G. Louie, Electron- phonon interaction using wannier functions, Phys. Rev. B76, 165108 (2007)

  49. [57]

    Dupuis, L

    N. Dupuis, L. Canet, A. Eichhorn, W. Metzner, J. M. Pawlowski, M. Tissier, and N. Wschebor, The nonper- turbative functional renormalization group and its ap- plications, Physics Reports The Nonperturbative Func- tional Renormalization Group and Its Applications,910, 1 (2021)

  50. [58]

    Classen, M

    L. Classen, M. M. Scherer, and C. Honerkamp, Insta- bilities on graphene’s honeycomb lattice with electron- phonon interactions, Phys. Rev. B90, 035122 (2014)

  51. [59]

    Lichtenstein, D

    J. Lichtenstein, D. S´ anchez de la Pe˜ na, D. Rohe, E. Di Napoli, C. Honerkamp, and S. Maier, High-performance 15 functional renormalization group calculations for in- teracting fermions, Computer Physics Communications 213, 100 (2017)

  52. [60]

    J. Zhan, Y. Gu, X. Wu, and J. Hu, Cooperation between electron-phonon coupling and electronic interaction in bi- layer nickelates la 3ni2o7, Phys. Rev. Lett.134, 136002 (2025)

  53. [61]

    Al-Eryani, S

    A. Al-Eryani, S. Andergassen, and M. M. Scherer, Inter- twined fluctuations and isotope effects in the hubbard- holstein model on the square lattice from functional renormalization, Phys. Rev. Res.7, 043052 (2025)

  54. [62]

    Fischer, L

    A. Fischer, L. Klebl, J. B. Profe, A. Rothstein, L. Waldecker, B. Beschoten, T. O. Wehling, and D. M. Kennes, Spin and charge fluctuation induced pairing in abcb tetralayer graphene, Phys. Rev. Res.6, L012003 (2024)

  55. [63]

    Husemann and M

    C. Husemann and M. Salmhofer, Efficient parametriza- tion of the vertex function, Ω scheme, and thet, t ′ hub- bard model at van hove filling, Phys. Rev. B79, 195125 (2009)

  56. [64]

    Beyer, J

    J. Beyer, J. B. Profe, and L. Klebl, Reference results for the momentum space functional renormalization group, The European Physical Journal B95, 65 (2022)

  57. [65]

    J. B. Profe and D. M. Kennes, TU2FRG: A scalable approach for truncated unity functional renormalization group in generic fermionic models, The European Phys- ical Journal B95, 60 (2022)

  58. [66]

    Wang, Z.-Z

    W.-S. Wang, Z.-Z. Li, Y.-Y. Xiang, and Q.-H. Wang, Competing electronic orders on kagome lattices at van hove filling, Phys. Rev. B87, 115135 (2013)

  59. [67]

    S´ anchez de la Pe˜ na,Competing Orders in Honeycomb Hubbard Models with Nonlocal Coulomb Interactions: A Functional Renormalization Group Approach, Ph.D

    D. S´ anchez de la Pe˜ na,Competing Orders in Honeycomb Hubbard Models with Nonlocal Coulomb Interactions: A Functional Renormalization Group Approach, Ph.D. the- sis, RWTH Aachen University (2019)

  60. [68]

    Klebl, Q

    L. Klebl, Q. Xu, A. Fischer, L. Xian, M. Claassen, A. Ru- bio, and D. M. Kennes, Moir´ e engineering of spin–orbit coupling in twisted platinum diselenide, Electronic Struc- ture4, 014004 (2022)

  61. [69]

    J. B. Profe, L. Klebl, F. Grandi, H. Hohmann, M. D¨ urrnagel, T. Schwemmer, R. Thomale, and D. M. Kennes, Kagome hubbard model from a functional renor- malization group perspective, Phys. Rev. Res.6, 043078 (2024)

  62. [70]

    J. B. Profe, L. C. Rhodes, M. D¨ urrnagel, R. Bisset, C. A. Marques, S. Chi, T. Schwemmer, R. Thomale, D. M. Kennes, C. A. Hooley, and P. Wahl, Magic angle of Sr2RuO4: Optimizing correlation-driven superconduc- tivity, Physical Review Research6, 043057 (2024)

  63. [71]

    Fischer, L

    A. Fischer, L. Klebl, V. Cr´ epel, S. Ryee, A. Rubio, L. Xian, T. O. Wehling, A. Georges, D. M. Kennes, and A. J. Millis, Theory of Intervalley-Coherent AFM Order and Topological Superconductivity in tWSe2, Physical Review X15, 041055 (2025)

  64. [72]

    J. Beck, J. Bodky, M. D¨ urrnagel, R. Thomale, J. In- gham, L. Klebl, and H. Hohmann, Kekul´ e order from diffuse nesting near higher-order Van Hove points, arXiv:2505.22725, accepted in Physical Review Letters (2025)

  65. [73]

    D¨ urrnagel, H

    M. D¨ urrnagel, H. Hohmann, A. Maity, J. Seufert, M. Klett, L. Klebl, and R. Thomale, Altermagnetic Phase Transition in a Lieb Metal, Physical Review Letters135, 036502 (2025)

  66. [74]

    C. Bigi, M. D¨ urrnagel, L. Klebl, A. Consiglio, G. Pokharel, M. Zonno, F. Bertran, P. Le F` evre, T. Jaouen, H. C. Tchouekem, P. Turban, A. De Vita, J. A. Miwa, J. W. Wells, D. Oh, R. Comin, R. Thomale, I. Zeljkovic, B. R. Ortiz, S. D. Wilson, G. Sangiovanni, F. Mazzola, and ...

  67. [75]

    Y. Guo, J. Cenker, A. Fischer, D. Mu˜ noz-Segovia, J. Pack, L. Holtzman, L. Klebl, K. Watanabe, T. Taniguchi, K. Barmak, J. Hone, A. Rubio, D. M. Kennes, A. J. Millis, A. Pasupathy, and C. R. Dean, An- gle evolution of the superconducting phase diagram in twisted bilayer WSe2,...

  68. [76]

    Nomura and R

    Y. Nomura and R. Arita, Ab initio downfolding for electron-phonon-coupled systems: Constrained density- functional perturbation theory, Phys. Rev. B92, 245108 (2015)

  69. [77]

    J. Hall, N. Ehlen, J. Berges, E. van Loon, C. van Efferen, C. Murray, M. R¨ osner, J. Li, B. V. Senkovskiy, M. Hell, M. Rolf, T. Heider, M. C. Asensio, J. Avila, L. Plucinski, T. Wehling, A. Gr¨ uneis, and T. Michely, Environmental control of charge density wave order in monol...

  70. [78]

    Giustino, Electron-phonon interactions from first prin- ciples, Rev

    F. Giustino, Electron-phonon interactions from first prin- ciples, Rev. Mod. Phys.89, 015003 (2017)

  71. [79]

    Gonze and C

    X. Gonze and C. Lee, Dynamical matrices, born effective charges, dielectric permittivity tensors, and interatomic force constants from density-functional perturbation the- ory, Phys. Rev. B55, 10355 (1997)

  72. [80]

    Baroni, S

    S. Baroni, S. de Gironcoli, A. Dal Corso, and P. Gi- annozzi, Phonons and related crystal properties from density-functional perturbation theory, Rev. Mod. Phys. 73, 515 (2001)

  73. [81]

    Berges, E

    J. Berges, E. G. C. P. van Loon, A. Schobert, M. R¨ osner, and T. O. Wehling, Ab initio phonon self-energies and fluctuation diagnostics of phonon anomalies: Lattice in- stabilities from dirac pseudospin physics in transition metal dichalcogenides, Phys. Rev. B101, 155107 (2020)

  74. [82]

    Meixner, H

    M. Meixner, H. Eßl, M. Reitner, A. Toschi, and T. Sch¨ afer, On degeneracies of density, magnetic, and pairing responses: How competing orders echo underly- ing symmetries in the hubbard model, arXiv:2606.24755 (2026)

  75. [83]

    C. J. Halboth and W. Metzner, Renormalization-group analysis of the two-dimensional hubbard model, Phys. Rev. B61, 7364 (2000)

  76. [84]

    Salmhofer and C

    M. Salmhofer and C. Honerkamp, Fermionic Renormal- ization Group Flows: Technique and Theory, Progress of Theoretical Physics105, 1 (2001)

  77. [85]

    Berges, A

    J. Berges, A. Schobert, E. G. C. P. van Loon, M. R¨ osner, and T. O. Wehling, Elphmod: Python modules for electron-phonon models, Zenodo (2025)

  78. [86]

    C. Xu, S. Wu, G.-X. Zhi, G. Cao, J. Dai, C. Cao, X. Wang, and H.-Q. Lin, Altermagnetic ground state in distorted Kagome metal CsCr3Sb5, Nature Communica- tions16, 3114 (2025)

  79. [87]

    C. Guo, G. Wagner, C. Putzke, D. Chen, K. Wang, L. Zhang, M. Gutierrez-Amigo, I. Errea, M. G. Vergniory, C. Felser, M. H. Fischer, T. Neupert, and P. J. W. Moll, Correlated order at the tipping point in the kagome metal CsV3Sb5, Nature Physics20, 579 (2024)

  80. [88]

    Enzner, J

    S. Enzner, J. Berges, A. Schobert, D. Oh, M. Kang, R. Comin, R. Thomale, T. O. Wehling, D. D. Sante, and G. Sangiovanni, Phonon fluctuation diagnostics: Origin of charge order in AV3Sb5 kagome metals, 16 arXiv:2504.07883 (2025)

  81. [89]

    Y. Cao, V. Fatemi, S. Fang, K. Watanabe, T. Taniguchi, E. Kaxiras, and P. Jarillo-Herrero, Unconventional super- conductivity in magic-angle graphene superlattices, Na- ture556, 43 (2018)

  82. [90]

    H. Zhou, L. Holleis, Y. Saito, L. Cohen, W. Huynh, C. L. Patterson, F. Yang, T. Taniguchi, K. Watanabe, and A. F. Young, Isospin magnetism and spin-polarized su- perconductivity in Bernal bilayer graphene, Science375, 774 (2022)

  83. [91]

    Y.-Z. Chou, F. Wu, J. D. Sau, and S. Das Sarma, Acoustic-phonon-mediated superconductivity in Bernal bilayer graphene, Physical Review B105, L100503 (2022)

  84. [92]

    Mæland, G

    K. Mæland, G. Sangiovanni, and B. Trauzettel, Mecha- nism for Nodal Topological Superconductivity on PtBi 2 Surface, arXiv:2512.09994 (2025)

  85. [93]

    Mæland, M

    K. Mæland, M. Bahari, and B. Trauzettel, Phonon- mediated intrinsic topological superconductivity in fermi arcs, Phys. Rev. B112, 104507 (2025)

  86. [94]

    Klebl and D

    L. Klebl and D. M. Kennes, Surface functional renormalization group for layered quantum materials, arXiv:2601.11055 (2026)

  87. [95]

    N. Li, J. Guan, L. Yan, X. Yan, M. Li, X. Liu, K. Zhang, F. Li, S. Cai, H. Dong, A. N-Diaye, M. Am- boage, J. Zhang, Y. Cao, H. Guo, Q. Kong, L. Sun, and W. Yang, Crystal and electronic structure studies of la4ni3o10-δunder high-pressure and low-temperature conditions, Journal...

  88. [96]

    Cercellier, C

    H. Cercellier, C. Monney, F. Clerc, C. Battaglia, L. De- spont, M. G. Garnier, H. Beck, P. Aebi, L. Patthey, H. Berger, and L. Forr´ o, Evidence for an excitonic in- sulator phase in 1t−tise 2, Phys. Rev. Lett.99, 146403 (2007)

  89. [97]

    Pashov, R

    D. Pashov, R. E. Larsen, M. D. Watson, S. Acharya, and M. van Schilfgaarde, Tise2 is a band insulator created by lattice fluctuations, not an excitonic insulator, npj Computational Materials11, 152 (2025)

  90. [98]

    M. Ren, F. Cheng, Y. Zhao, M. Gu, Q. Cheng, B. Yan, Q. Liu, X. Ma, Q. Xue, and C.-L. Song, Chiral charge density wave and backscattering-immune orbital texture in monolayer 1t-tite2, Nano Letters23, 10081 (2023)

  91. [99]

    Zhang, K

    S. Zhang, K. Luo, and T. Zhang, Understanding chiral charge-density wave by frozen chiral phonon, npj Com- putational Materials10, 264 (2024)

  92. [100]

    Gariglio, A

    S. Gariglio, A. Fˆ ete, and J.-M. Triscone, Electron con- finement at the LaAlO3/SrTiO3 interface, Journal of Physics: Condensed Matter27, 283201 (2015)

  93. [101]

    M. S. Scheurer and J. Schmalian, Topological supercon- ductivity and unconventional pairing in oxide interfaces, Nature Communications6, 6005 (2015)

  94. [102]

    Diego and M

    J. Diego and M. Calandra, Fermi surface geome- try and momentum dependent electron-phonon cou- pling drive the charge density wave in quasi-1D ZrTe3, arXiv:2602.04534 (2026)

Pith tools

Reviewed July 10, 2026 · model on record in the stance chip above.