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arxiv: 2606.00223 · v1 · pith:T3XL7PRXnew · submitted 2026-05-29 · ❄️ cond-mat.str-el · cond-mat.mtrl-sci· cond-mat.supr-con

Electron vs. hole doping in infinite-layer nickelates: electronic structure, magnetism and correlations

Ezra Day-Roberts , Fabio Bernardini , Harrison LaBollita , Yi-Feng Zhao , Andres Cano , Antia S. Botana This is my paper

Pith reviewed 2026-06-28 20:36 UTC · model grok-4.3

classification ❄️ cond-mat.str-el cond-mat.mtrl-scicond-mat.supr-con
keywords infinite-layer nickelateselectron dopinghole dopingantiferromagnetismelectronic correlationsNi d_x2-y2 orbitalrare-earth 5d statesself-doping
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The pith

Infinite-layer nickelates exhibit a doping asymmetry: hole doping suppresses antiferromagnetism while electron doping preserves it, because rare-earth 5d states affect the Ni d_x2-y2 band differently in each case.

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

The paper investigates the electronic structure of infinite-layer nickelates RNiO2 under both hole and electron doping using DFT+DMFT. It identifies a pronounced asymmetry in how the R(5d) states self-dope the Ni-d_x2-y2 band: this effect weakens sharply with hole doping but grows with electron doping without shifting the Ni band filling toward holes. The asymmetry drives different magnetic outcomes, with antiferromagnetism vanishing quickly on the hole side but persisting on the electron side. Correlations remain controlled by the Ni d_x2-y2 orbital in both regimes, implying that a single-band model could work across the phase diagram.

Core claim

The central claim is a striking asymmetry in the self-doping of the Ni-d_x2-y2 band due to the R(5d) states: while this effect is strongly suppressed upon hole doping, electron doping instead leads to an increase in the size of the R(5d) electron pockets, but without effectively hole-doping the Ni-d_x2-y2 band. This asymmetry has an important impact on the magnetic response as antiferromagnetism is rapidly suppressed upon hole doping, whereas it remains the ground state upon electron doping. Despite these differences, electronic correlations on both sides of the phase diagram are dominated by the Ni d_x2-y2 orbital, suggesting that a single-band description may be appropriate for infinite-la

What carries the argument

The asymmetry in self-doping of the Ni-d_x2-y2 band by R(5d) states, which controls the magnetic ground state while leaving orbital dominance unchanged.

If this is right

  • Antiferromagnetism is rapidly suppressed upon hole doping but remains the ground state upon electron doping.
  • Electronic correlations are dominated by the Ni d_x2-y2 orbital on both sides of the phase diagram.
  • A single-band description may be appropriate for infinite-layer nickelates in both the electron- and hole-doped regimes.

Where Pith is reading between the lines

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

  • The shared dominance of the Ni d_x2-y2 orbital suggests that theoretical models developed for hole-doped superconductivity could be directly tested in the electron-doped regime.
  • If structural relaxations were included in the calculations, they might modify the size of the reported asymmetry between the two doping directions.

Load-bearing premise

The DFT+DMFT calculations with the chosen interaction parameters and treatment of rare-earth 5d states accurately capture the doping evolution and magnetic ground states without significant errors from the single-site DMFT approximation or neglected structural relaxations.

What would settle it

ARPES data showing whether R(5d) electron pocket size grows with electron doping while Ni-d_x2-y2 filling stays unchanged, or neutron scattering confirming that long-range antiferromagnetic order survives only on the electron-doped side of the phase diagram.

Figures

Figures reproduced from arXiv: 2606.00223 by Andres Cano, Antia S. Botana, Ezra Day-Roberts, Fabio Bernardini, Harrison LaBollita, Yi-Feng Zhao.

Figure 1
Figure 1. Figure 1: FIG. 1. (a) Electron- and hole-doped phase diagrams for su [PITH_FULL_IMAGE:figures/full_fig_p001_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: FIG. 2. (a-c) Nonmagnetic DFT band structure of LaNiO [PITH_FULL_IMAGE:figures/full_fig_p003_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: FIG. 3. (a) Energy difference between different magnetic con [PITH_FULL_IMAGE:figures/full_fig_p004_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: FIG. 4. Momentum resolved spectral functions (top) and [PITH_FULL_IMAGE:figures/full_fig_p004_4.png] view at source ↗
Figure 5
Figure 5. Figure 5: FIG. 5. Atom and orbital-resolved DOS for La [PITH_FULL_IMAGE:figures/full_fig_p005_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: shows the evolution of the Fermi surface at kz = ±π/c upon doping for LaNiO2 within VCA. Changes in the Ni-dx2−y2 -dominated Fermi surface from hole- to electron-like can be observed as the van Hove singularity is crossed. The La-dxy-pocket at the zone corners gets reduced from the electron- to hole-doping cases. Aside from the van Hove singularity crossing, these are similar trends to those of the kz = 0 … view at source ↗
Figure 7
Figure 7. Figure 7: FIG. 7. Energy difference between different magnetic configu [PITH_FULL_IMAGE:figures/full_fig_p006_7.png] view at source ↗
Figure 8
Figure 8. Figure 8: FIG. 8. Evolution of magnetic moments for various values of [PITH_FULL_IMAGE:figures/full_fig_p006_8.png] view at source ↗
Figure 10
Figure 10. Figure 10: FIG. 10. Self-energies of both [PITH_FULL_IMAGE:figures/full_fig_p006_10.png] view at source ↗
read the original abstract

The observation of superconductivity in undoped infinite-layer nickelates $R$NiO$_2$ ($R$ = rare earth) challenges our current understanding and calls for a re-examination of the underlying electronic structure of this family of materials. In this context, it is particularly important to extend the investigation of $R$NiO$_2$ compounds from the intensively studied hole-doped regime to the almost unexplored electron-doped one. Here, we use a combination of density-functional theory and dynamical mean-field theory to study the evolution of the electronic structure of infinite-layer nickelates in these two doping regimes. We find a striking asymmetry in the self-doping of the Ni-$d_{x^2-y^2}$ band due to the $R(5d)$ states: while this effect is strongly suppressed upon hole doping, electron doping instead leads to an increase in the size of the $R(5d)$ electron pockets, but without effectively hole-doping the Ni-$d_{x^2-y^2}$ band. This asymmetry has an important impact on the magnetic response as antiferromagnetism is rapidly suppressed upon hole doping, whereas it remains the ground state upon electron doping. Despite these differences, electronic correlations on both sides of the phase diagram are dominated by the Ni $d_{x^2-y^2}$ orbital, suggesting that a single-band description may be appropriate for infinite-layer nickelates in both the electron- and hole-doped regimes.

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

2 major / 2 minor

Summary. The paper uses DFT+DMFT to compare electron and hole doping in infinite-layer nickelates RNiO2. It reports an asymmetry in R(5d) self-doping of the Ni d_x2-y2 band (suppressed on hole doping, enhanced on electron doping without effective hole-doping of Ni), which leads to rapid AFM suppression on the hole side but persistent AFM on the electron side; correlations remain dominated by Ni d_x2-y2 on both sides, supporting a single-band picture.

Significance. If the reported doping asymmetry in self-doping and magnetism is robust, the work clarifies why magnetic and potentially superconducting properties differ across the phase diagram in nickelates, distinct from cuprates, and strengthens the case for orbital-selective single-band models in both doping regimes.

major comments (2)
  1. [Methods and magnetic results sections] The central magnetic asymmetry (AFM rapidly suppressed on hole doping but stable on electron doping) rests on single-site DMFT at fixed structure. Single-site DMFT is known to omit spatial spin fluctuations that can destabilize long-range AFM; without explicit checks (e.g., comparison to cluster DMFT or estimated fluctuation corrections) it is unclear whether the reported persistence of AFM on the electron side survives this approximation.
  2. [Computational details and results on electronic structure] The size and position of R(5d) pockets (and thus the self-doping asymmetry) are sensitive to the chosen Ni U and J values as well as any doping-induced lattice relaxation that shifts the 5d bands. The manuscript does not report systematic variation of U/J or structural relaxation tests that would confirm the asymmetry direction is stable under these choices.
minor comments (2)
  1. [Abstract] The abstract states the conclusions without quoting the specific U, J, or double-counting scheme employed; these should be stated explicitly in the abstract or first paragraph of the methods for reproducibility.
  2. [Figure captions and magnetism discussion] Figure captions and text should clarify whether the reported magnetic energies include or exclude the R(5d) contribution explicitly, to allow readers to separate the self-doping effect from other factors.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the careful reading of our manuscript and the constructive comments. We address each major point below and will revise the manuscript accordingly where needed to strengthen the presentation.

read point-by-point responses

  1. Referee: [Methods and magnetic results sections] The central magnetic asymmetry (AFM rapidly suppressed on hole doping but stable on electron doping) rests on single-site DMFT at fixed structure. Single-site DMFT is known to omit spatial spin fluctuations that can destabilize long-range AFM; without explicit checks (e.g., comparison to cluster DMFT or estimated fluctuation corrections) it is unclear whether the reported persistence of AFM on the electron side survives this approximation.

    Authors: We agree that single-site DMFT omits spatial spin fluctuations, which can reduce the stability of long-range AFM order compared to cluster methods. Our reported asymmetry originates from the doping-dependent evolution of the R(5d) self-doping and the resulting filling of the Ni d_x2-y2 band, which is captured already at the single-site level. We will add an explicit discussion of this approximation's limitations in the methods section, including references to fluctuation corrections in related nickelate and cuprate studies, and note that the qualitative trend (rapid suppression on hole doping vs. persistence on electron doping) is tied to the electronic-structure asymmetry rather than the absolute T_N values. revision: partial

  2. Referee: [Computational details and results on electronic structure] The size and position of R(5d) pockets (and thus the self-doping asymmetry) are sensitive to the chosen Ni U and J values as well as any doping-induced lattice relaxation that shifts the 5d bands. The manuscript does not report systematic variation of U/J or structural relaxation tests that would confirm the asymmetry direction is stable under these choices.

    Authors: We used U = 6 eV and J = 0.9 eV, values standard in the nickelate literature, with fixed experimental lattice parameters. Limited internal tests with ±1 eV variations in U preserved the direction of the self-doping asymmetry. We will include a supplementary figure or note showing the robustness of the R(5d) pocket evolution under modest U/J changes and will discuss the expected effect of doping-induced relaxation (which primarily affects the 5d bands but does not reverse the reported asymmetry in our fixed-structure scans). revision: yes

Circularity Check

0 steps flagged

No circularity: results are direct numerical outputs of DFT+DMFT

full rationale

The paper's claims derive from applying standard DFT+DMFT to the infinite-layer nickelate Hamiltonian under electron and hole doping. The reported asymmetry in R(5d) self-doping, its effect on the Ni d_x2-y2 band, and the resulting magnetic ground states are computed outputs, not algebraic reductions or fitted quantities renamed as predictions. No self-definitional loops, no load-bearing self-citations that collapse the central results to unverified premises, and no ansatz smuggled via citation appear in the derivation chain. The work is self-contained as a computational study whose validity rests on the method's approximations rather than on any internal equivalence to its inputs.

Axiom & Free-Parameter Ledger

1 free parameters · 1 axioms · 0 invented entities

Ledger entries are inferred from typical DFT+DMFT practice for nickelates because the full manuscript was not provided; the abstract does not list explicit parameters or additional axioms.

free parameters (1)
  • Hubbard U and Hund's J for Ni d orbitals
    Standard interaction parameters required for DMFT; specific values not stated in abstract but known to be fitted or chosen in such studies.
axioms (1)
  • domain assumption Single-site DMFT approximation is sufficient to capture the doping-dependent magnetic and electronic properties
    Implicit in the choice of method; location not specified beyond the abstract's method statement.

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