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arxiv: 2312.09014 · v3 · submitted 2023-12-14 · ❄️ cond-mat.str-el · cond-mat.supr-con

Hole doping and electronic correlations in Cr-substituted BaFe₂As₂

Pith reviewed 2026-05-24 04:33 UTC · model grok-4.3

classification ❄️ cond-mat.str-el cond-mat.supr-con
keywords Cr-substituted BaFe2As2Hund's correlationsARPESDFT+DMFThole dopingspin density waveiron pnictideselectronic correlations
0
0 comments X

The pith

Cr substitution in BaFe2As2 adds holes near the Fermi surface and creates Hund's correlations that leave the spin-density-wave suppression mechanism unchanged.

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

The work examines why chromium substitution in BaFe2As2 eliminates superconductivity despite suppressing the spin-density-wave transition temperature in the same way manganese substitution does. ARPES measurements combined with DFT+DMFT calculations show that chromium produces an effective hole doping of states at the Fermi surface that matches the virtual crystal approximation. The imaginary part of the self-energy on the main d_yz bands displays a fractional scaling with binding energy, the hallmark of Hund's correlations. These results establish that the material stays a correlated electron system and that the observed Fermi-surface shifts do not cause the drop in magnetic ordering temperature.

Core claim

Incorporating Cr leads to an effective hole doping of the states near the FS, which is well described within the virtual crystal approximation. The electronic band spectra with main d_yz-orbital character exhibit a fractional scaling of the imaginary part of self-energy as a function of the binding energy, a signature of Hund's correlations. CrBFA is therefore a correlated electron system in which the changes in the FS as a function of Cr are unrelated to the suppression of T_SDW. The absence of SC is primarily due to the competition between Cr local moments and the Fe-derived itinerant spin fluctuations.

What carries the argument

Fractional scaling of the imaginary self-energy versus binding energy on the d_yz bands, which marks Hund's correlations, together with virtual crystal approximation modeling of the hole doping.

If this is right

  • Fermi-surface modifications with Cr content do not drive the observed reduction in spin-density-wave transition temperature.
  • CrBFA remains a correlated electron system controlled by Hund's physics.
  • Superconductivity is absent because chromium local moments compete directly with iron-derived itinerant spin fluctuations.
  • The matching T_SDW suppression curves for Cr and Mn substitutions occur through unrelated microscopic processes.

Where Pith is reading between the lines

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

  • Local moments introduced by substituents can block superconductivity even when they produce doping levels comparable to non-magnetic dopants.
  • Applying the same ARPES and self-energy analysis to other transition-metal substitutions would test whether Hund's correlations routinely decouple Fermi-surface evolution from magnetic ordering.
  • If moment competition dominates, external suppression of the Cr moment size could restore superconductivity at fixed hole doping.

Load-bearing premise

The observed self-energy scaling and Fermi-surface evolution suffice to rule out any Fermi-surface role in suppressing the spin-density-wave order, and moment competition is the main reason superconductivity is missing.

What would settle it

Observation of superconductivity in Cr-substituted samples in which the chromium local moments are quenched (for example by pressure or co-doping) while the hole doping level at the Fermi surface stays the same.

Figures

Figures reproduced from arXiv: 2312.09014 by Bj\"orn Salzmann, C. Adriano, Fernando A. Garcia, G. S. Freitas, K. R. Pakuszewski, Marli R. Cantarino, Pedro H. A. Moya, P. G. Pagliuso, Wagner R. da Silva Neto, Walber H. Brito.

Figure 1
Figure 1. Figure 1: (a)-(c) Overview of the ARPES measured electronic band structure of the BFA, Cr3% and Cr8.5% materials. As indicated, measurements were taken along the ΓX and ΓM directions and for LH and LV polarizations. The dots represent the band positions as obtained from the second derivative of the band maps and MDC analysis. DFT+DMFT spectral functions for the paramagnetic phases at T = 150 K for (d) BFA and (e) Cr… view at source ↗
Figure 2
Figure 2. Figure 2: (a) − (c) Measured Fermi Surface of the BFA, Cr3% and Cr8.5% materials with LV polarization, showing the BZ draw and its high-symmetry points. The red dashed line indicates the XY cut based upon which the electron pockets of 3(h) were reconstructed. (d)−(f) DFT+DMFT paramagnetic (T = 150 K) Fermi Surface for BFA, Cr3% and Cr8.5%. the ARPES band map measurements, it is possible to extract the electronic ban… view at source ↗
Figure 3
Figure 3. Figure 3: (a) and (b) experimentally determined FSs of the Cr8.5% sample with LV polarization at two different geometries. The BZ and high-symmetry points are indicated for reference and the colored dashed lines (green and magenta) are guides to eyes indicating the FS cuts #1 and #2 from which the electron pockets presented in (f) and (h) were reconstructed. (c) − (f) Survey of the band state positions, in the vicin… view at source ↗
Figure 4
Figure 4. Figure 4: (a)-(b) ARPES spectral function analysis for the electronic band with [PITH_FULL_IMAGE:figures/full_fig_p008_4.png] view at source ↗
Figure 5
Figure 5. Figure 5: (a) DFT+DMFT spectral functions for the paramagnetic phases at [PITH_FULL_IMAGE:figures/full_fig_p011_5.png] view at source ↗
read the original abstract

Superconductivity (SC) is absent in Cr-substituted BaFe$_{2}$As$_{2}$ (CrBFA), a well-established but poorly understood topic. Additionally, the suppression of the spin density wave transition temperature ($T_{\text{SDW}}$) in CrBFA and Mn-substituted BaFe$_{2}$As$_{2}$ (MnBFA) coincides as a function of Cr/Mn content, despite the distinct electronic effects of these substitutions. In this work, we employ angle-resolved photoemission spectroscopy (ARPES) and combined density functional theory plus dynamical mean field theory calculations (DFT+DMFT) to address the evolution of the Fermi surface (FS) and electronic correlations in CrBFA. Our findings reveal that incorporating Cr leads to an effective hole doping of the states near the FS, which is well described within the virtual crystal approximation (VCA). We analyzed the electronic band spectra with main $d_{yz}$-orbital character and found a fractional scaling of the imaginary part of self-energy as a function of the binding energy, a signature property of Hund's correlations. We conclude that CrBFA is a correlated electron system and the changes in the FS as a function of Cr are unrelated to the suppression of $T_{\text{SDW}}$. We suggest that the absence of SC is primarily due to the competition between Cr local moments and the Fe-derived itinerant spin fluctuations.

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 / 1 minor

Summary. The manuscript reports ARPES spectra and DFT+DMFT calculations on Cr-substituted BaFe₂As₂. It finds that Cr substitution produces an effective hole doping of states near the Fermi surface that is captured by the virtual crystal approximation, observes a fractional power-law scaling ImΣ(ω) ~ ω^α on the d_yz bands as a signature of Hund's correlations, concludes that the system remains a correlated metal, and states that the observed Fermi-surface evolution is unrelated to the suppression of T_SDW. The authors suggest that the absence of superconductivity is due to competition between Cr local moments and Fe-derived itinerant spin fluctuations.

Significance. The ARPES+DMFT results on the applicability of VCA and the presence of Hund's scaling provide concrete data on how Cr substitution modifies the electronic structure of BaFe₂As₂. If the interpretive link between these observations and the absence of superconductivity can be strengthened, the work would help distinguish local-moment versus Fermi-surface mechanisms in iron pnictides.

major comments (2)
  1. [Abstract / final paragraph] Abstract and final paragraph: the suggestion that absent superconductivity is 'primarily due to the competition between Cr local moments and the Fe-derived itinerant spin fluctuations' is presented without any calculation of moment-fluctuation coupling, scattering rates, or comparison to a model in which local-moment scattering suppresses Tc. The ARPES/DMFT data establish hole doping and self-energy scaling but do not quantitatively test this mechanism.
  2. [Discussion of T_SDW suppression] Discussion of T_SDW(x): the claim that Fermi-surface changes are unrelated to T_SDW suppression rests on the observation that T_SDW(x) tracks MnBFA, yet the manuscript does not show a direct mapping of the VCA hole-doping level onto the doping scale at which T_SDW is suppressed in other series (e.g., K- or Co-doped BaFe₂As₂) or demonstrate that the observed doping shift is too small to account for the measured T_SDW reduction.
minor comments (1)
  1. [Self-energy analysis] The exponent α in the reported ImΣ(ω) ~ ω^α scaling is not stated numerically, nor is its doping dependence or uncertainty shown; adding these values would clarify the strength of the Hund's-correlation claim.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the careful reading and constructive comments on our manuscript. We address each major comment below and indicate the revisions made to the manuscript.

read point-by-point responses
  1. Referee: [Abstract / final paragraph] Abstract and final paragraph: the suggestion that absent superconductivity is 'primarily due to the competition between Cr local moments and the Fe-derived itinerant spin fluctuations' is presented without any calculation of moment-fluctuation coupling, scattering rates, or comparison to a model in which local-moment scattering suppresses Tc. The ARPES/DMFT data establish hole doping and self-energy scaling but do not quantitatively test this mechanism.

    Authors: We agree that the proposed mechanism for the absence of superconductivity is interpretive and lacks a quantitative calculation of moment-fluctuation coupling or scattering rates within this study. The ARPES and DFT+DMFT results establish the hole doping via VCA and the Hund's scaling of the self-energy, while the similarity of T_SDW suppression to Mn substitution (despite different electronic effects) supports that Fermi-surface evolution is not the driver. In the revised manuscript we have rephrased the abstract and final paragraph to present the local-moment competition as a plausible interpretation consistent with our data and prior reports of Cr local moments, while explicitly noting that a microscopic model of the interaction would be required for quantitative confirmation. revision: yes

  2. Referee: [Discussion of T_SDW suppression] Discussion of T_SDW(x): the claim that Fermi-surface changes are unrelated to T_SDW suppression rests on the observation that T_SDW(x) tracks MnBFA, yet the manuscript does not show a direct mapping of the VCA hole-doping level onto the doping scale at which T_SDW is suppressed in other series (e.g., K- or Co-doped BaFe₂As₂) or demonstrate that the observed doping shift is too small to account for the measured T_SDW reduction.

    Authors: The referee is correct that a direct comparison of the VCA-derived hole-doping level to the critical doping scales in K- and Co-substituted series would strengthen the argument. We have added to the revised manuscript an explicit mapping of the effective hole doping obtained from VCA in CrBFA onto the doping axis of K- and Co-doped BaFe₂As₂. This shows that the VCA hole doping remains well below the level at which T_SDW is suppressed in those series, even at Cr concentrations where T_SDW has already dropped substantially. The discussion section has been updated to include this comparison and to clarify why the observed Fermi-surface shift cannot account for the measured T_SDW reduction. revision: yes

Circularity Check

0 steps flagged

No significant circularity; key claims are interpretive inferences from ARPES and DFT+DMFT data

full rationale

The paper's derivation chain consists of ARPES measurements of the Fermi surface and band dispersions in Cr-substituted BaFe2As2, combined with standard DFT+DMFT calculations under the virtual crystal approximation to model effective hole doping. The observed fractional scaling ImΣ(ω) ~ ω^α for d_yz bands is reported as a direct signature of Hund's correlations from the computed self-energy, and the conclusion that FS evolution is unrelated to T_SDW suppression follows as an interpretation of these independent data sets. The suggestion regarding competition between Cr local moments and Fe fluctuations is explicitly labeled as such in the abstract and final paragraph, without any fitted parameter, self-citation chain, or ansatz that reduces the result to its own inputs by construction. No load-bearing steps match the enumerated circularity patterns.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

Abstract-only review; no explicit free parameters, axioms, or invented entities are stated. Standard DMFT assumptions (Hubbard U, Hund's J) and ARPES matrix-element interpretations are implicit but not quantified.

pith-pipeline@v0.9.0 · 5843 in / 1157 out tokens · 22757 ms · 2026-05-24T04:33:34.601665+00:00 · methodology

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Reference graph

Works this paper leans on

67 extracted references · 67 canonical work pages

  1. [1]

    Kamihara, T

    Y. Kamihara, T. Watanabe, M. Hirano and H. Hosono, Iron-Based Layered Superconductor La[O1-xFx]FeAs (x = 0.05-0.12) with Tc = 26 K, J. Am. Chem. Soc. 130(11), 3296 (2008), doi:10.1021/ja800073m

  2. [2]

    Zhi-An, L

    R. Zhi-An, L. Wei, Y. Jie, Y. Wei, S. Xiao-Li, Zheng-Cai, C. Guang-Can, D. Xiao- Li, S. Li-Ling, Z. Fang and Z. Zhong-Xian,Superconductivity at 55 K in Iron-Based F-Doped Layered Quaternary Compound Sm[O1-xFx] FeAs, Chinese Physics Letters 25(6), 2215 (2008), doi:10.1088/0256-307X/25/6/080

  3. [3]

    Hosono and K

    H. Hosono and K. Kuroki, Iron-based superconductors: Current status of materials and pairing mechanism, Physica C: Superconductivity and its Applications514, 399 (2015), doi:https://doi.org/10.1016/j.physc.2015.02.020, Superconducting Materials: Conventional, Unconventional and Undetermined

  4. [4]

    Rotter, M

    M. Rotter, M. Tegel, D. Johrendt, I. Schellenberg, W. Hermes and R. Pöttgen,Spin- density-wave anomaly at 140 k in the ternary iron arsenide bafe2as2, Phys. Rev. B 78, 020503(R) (2008), doi:10.1103/PhysRevB.78.020503

  5. [5]

    M. G. Kim, R. M. Fernandes, A. Kreyssig, J. W. Kim, A. Thaler, S. L. Bud’ko, P. C. Canfield, R. J. McQueeney, J. Schmalian and A. I. Goldman, Character of the structural and magnetic phase transitions in the parent and electron-doped BaFe2As2 compounds, Physical Review B 83(13), 134522 (2011), doi:10.1103/PhysRevB.83.134522

  6. [6]

    N. Ni, A. Thaler, A. Kracher, J. Q. Yan, S. L. Bud’ko and P. C. Canfield,Phase diagrams of Ba(Fe1−xMx)2As2 single crystals (M = Rh and Pd), Physical Review B 80(2), 024511 (2009), doi:10.1103/PhysRevB.80.024511

  7. [7]

    A. S. Sefat, R. Jin, M. A. McGuire, B. C. Sales, D. J. Singh and D. Mandrus, Superconductivity at 22 K in co-doped BaFe2As2 crystals, Phys. Rev. Lett. 101, 117004 (2008), doi:10.1103/PhysRevLett.101.117004

  8. [8]

    L. J. Li, Y. K. Luo, Q. B. Wang, H. Chen, Z. Ren, Q. Tao, Y. K. Li, X. Lin, M. He, Z. W. Zhu, G. H. Cao and Z. A. Xu, Superconductivity induced by Ni doping in BaFe2As2 singlecrystals, New Journal of Physics 11(2), 025008 (2009), doi:10.1088/1367-2630/11/2/025008

  9. [9]

    J.-H. Chu, J. G. Analytis, C. Kucharczyk and I. R. Fisher,Determination of the phase diagram of the electron-doped superconductor Ba(Fe1−xCox)2As2, Phys. Rev. B 79, 014506 (2009), doi:10.1103/PhysRevB.79.014506. 12 REFERENCES REFERENCES

  10. [10]

    Jiang, H

    S. Jiang, H. Xing, G. Xuan, C. Wang, Z. Ren, C. Feng, J. Dai, Z. Xu and G. Cao, Superconductivity up to 30 k in the vicinity of the quantum critical point in BaFe2(As1−xPx)2, Journal of Physics: Condensed Matter21(38), 382203 (2009), doi:10.1088/0953-8984/21/38/382203

  11. [11]

    S. R. Saha, T. Drye, K. Kirshenbaum, N. P. Butch, P. Y. Zavalij and J. Paglione, Superconductivity at 23 K in Pt doped BaFe2As2 single crystals, Journal of Physics: Condensed Matter22(7), 072204 (2010), doi:10.1088/0953-8984/22/7/072204

  12. [12]

    Rotter, M

    M. Rotter, M. Tegel and D. Johrendt, Superconductivity at 38 K in the iron arsenide (Ba1−xKx)Fe2As2, Phys. Rev. Lett. 101, 107006 (2008), doi:10.1103/PhysRevLett.101.107006

  13. [13]

    Sasmal, B

    K. Sasmal, B. Lv, B. Lorenz, A. M. Guloy, F. Chen, Y.-Y. Xue and C.-W. Chu, Superconducting fe-based compounds (A1−xSrx)Fe2As2 with A = K and cs with transition temperatures up to 37 K, Phys. Rev. Lett. 101, 107007 (2008), doi:10.1103/PhysRevLett.101.107007

  14. [15]

    R. M. Fernandes and A. V. Chubukov,Low-energy microscopic models for iron-based superconductors: a review, Rep. Prog. Phys.80(1), 014503 (2016), doi:10.1088/1361- 6633/80/1/014503

  15. [16]

    Chubukov, Pairing Mechanism in Fe-Based Superconductors, Annual Review of Condensed Matter Physics3(1), 57 (2012), doi:10.1146/annurev-conmatphys-020911- 125055

    A. Chubukov, Pairing Mechanism in Fe-Based Superconductors, Annual Review of Condensed Matter Physics3(1), 57 (2012), doi:10.1146/annurev-conmatphys-020911- 125055

  16. [17]

    Haule and G

    K. Haule and G. Kotliar,Coherence–incoherence crossover in the normal state of iron oxypnictides and importance of Hund’s rule coupling, New Journal of Physics11(2), 025021 (2009), doi:10.1088/1367-2630/11/2/025021

  17. [18]

    Z. P. Yin, K. Haule and G. Kotliar,Kinetic frustration and the nature of the magnetic and paramagnetic states in iron pnictides and iron chalcogenides, Nature Materials 10(12), 932 (2011), doi:10.1038/NMAT3120

  18. [19]

    Z. P. Yin, K. Haule and G. Kotliar,Magnetism and charge dynamics in iron pnictides, Nature Physics7(4), 294 (2011), doi:10.1038/NPHYS1923

  19. [20]

    Bascones, B

    E. Bascones, B. Valenzuela and M. Jose Calderon, Magnetic interactions in iron superconductors: A review, Comptes Rendus Physique 17(1-2), 36 (2016), doi:10.1016/j.crhy.2015.05.004

  20. [21]

    R. M. Fernandes, A. I. Coldea, H. Ding, I. R. Fisher, P. J. Hirschfeld and G. Kotliar, Iron pnictides and chalcogenides: a new paradigm for superconductivity, Nature 601(7891), 35 (2022), doi:10.1038/s41586-021-04073-2

  21. [22]

    T.-H. Lee, A. Chubukov, H. Miao and G. Kotliar, Pairing Mechanism in Hund’s Metal Superconductors and the Universality of the Superconducting Gap to Critical Temperature Ratio, Physical Review Letters 121(18), 187003 (2018), doi:10.1103/PhysRevLett.121.187003. 13 REFERENCES REFERENCES

  22. [23]

    A. S. Sefat, D. J. Singh, L. H. VanBebber, Y. Mozharivskyj, M. A. McGuire, R. Jin, B. C. Sales, V. Keppens and D. Mandrus, Absence of superconductivity in hole-doped BaFe2−xCrxAs2 single crystals, Phys. Rev. B 79, 224524 (2009), doi:10.1103/PhysRevB.79.224524

  23. [24]

    Thaler, H

    A. Thaler, H. Hodovanets, M. S. Torikachvili, S. Ran, A. Kracher, W. Straszheim, J. Q. Yan, E. Mun and P. C. Canfield, Physical and magnetic properties of Ba(Fe1−xMnx)2As2 single crystals, Physical Review B 84(14), 144528 (2011), doi:10.1103/PhysRevB.84.144528

  24. [25]

    Spectral analysis of finite-time correlation matrices near equilibrium phase transitions

    X.-G. Li, J.-M. Sheng, C.-K. Tian, Y.-Y. Wang, T.-L. Xia, L. Wang, F. Ye, W. Tian, J.-C. Wang, J.-J. Liu, H.-X. Zhang, W. Baoet al., Effects of vanadium doping on BaFe2As2, Europhysics Letters 122(6), 67006 (2018), doi:10.1209/0295- 5075/122/67006

  25. [26]

    Texier, Y

    Y. Texier, Y. Laplace, P. Mendels, J. T. Park, G. Friemel, D. L. Sun, D. S. Inosov, C. T. Lin and J. Bobroff, Mn local moments prevent superconductivity in iron pnictides Ba(Fe1−xMnx)2As2, EPL (Europhysics Letters)99(1), 17002 (2012), doi:10.1209/0295-5075/99/17002

  26. [27]

    Suzuki, T

    H. Suzuki, T. Yoshida, S. Ideta, G. Shibata, K. Ishigami, T. Kadono, A. Fujimori, M. Hashimoto, D. H. Lu, Z.-X. Shen, K. Ono, E. Sakai et al., Absence of superconductivity in the hole-doped Fe pnictide Ba(Fe1−xMnx)2As2: Photoemission and x-ray absorption spectroscopy studies, Physical Review B 88(10), 100501(R) (2013), doi:10.1103/PhysRevB.88.100501

  27. [28]

    G. S. Tucker, D. K. Pratt, M. G. Kim, S. Ran, A. Thaler, G. E. Granroth, K. Marty, W. Tian, J. L. Zarestky, M. D. Lumsden, S. L. Bud’ko, P. C. Canfield et al., Competition between stripe and checkerboard magnetic instabilities in Mn-doped BaFe2As2, Physical Review B 86(2), 020503(R) (2012), doi:10.1103/PhysRevB.86.020503

  28. [29]

    F. A. Garcia, O. Ivashko, D. E. McNally, L. Das, M. M. Piva, C. Adriano, P. G. Pagliuso, J. Chang, T. Schmitt and C. Monney, Anisotropic magnetic excitations and incipient Néel order in Ba(Fe1−xMnx)2As2, Phys. Rev. B 99, 115118 (2019), doi:10.1103/PhysRevB.99.115118

  29. [30]

    M. R. Cantarino, K. R. Pakuszewski, B. Salzmann, P. H. A. Moya, W. R. d. S. Neto, G. S. Freitas, P. G. Pagliuso, W. H. Brito, C. Monney, C. Adriano and F. A. Garcia, Incoherent electronic band states in Mn-substituted BaFe2As2, Phys. Rev. B 108, 245124 (2023), doi:10.1103/PhysRevB.108.245124

  30. [31]

    R. M. Fernandes and A. J. Millis, Suppression of Superconductivity by Néel-Type Magnetic Fluctuations in the Iron Pnictides, Physical Review Letters110(11), 117004 (2013), doi:10.1103/PhysRevLett.110.117004

  31. [32]

    M. N. Gastiasoro and B. M. Andersen, Enhancement of Magnetic Stripe Order in Iron-Pnictide Superconductors from the Interaction between Conduction Electrons and Magnetic Impurities, Physical Review Letters113(6), 067002 (2014), doi:10.1103/PhysRevLett.113.067002

  32. [33]

    M. N. Gastiasoro, F. Bernardini and B. M. Andersen,Unconventional Disorder Effects in Correlated Superconductors, Physical Review Letters 117(25), 257002 (2016), doi:10.1103/PhysRevLett.117.257002. 14 REFERENCES REFERENCES

  33. [34]

    Kobayashi, M

    T. Kobayashi, M. Nakajima, S. Miyasaka and S. Tajima,Carrier localization due to local magnetic order induced by magnetic impurities in Ba(Fe1−xT Mx)2As2 (T M = Mn and Cr) as seen via optical spectra, Physical Review B 94(22), 224516 (2016), doi:10.1103/PhysRevB.94.224516

  34. [35]

    J. P. Clancy, B. D. Gaulin and A. S. Sefat,High-resolution x-ray scattering studies of structural phase transitions in Ba(Fe1−xCrx)2As2, Physical Review B85(5), 054115 (2012), doi:10.1103/PhysRevB.85.054115

  35. [36]

    Marty, A

    K. Marty, A. D. Christianson, C. H. Wang, M. Matsuda, H. Cao, L. H. VanBebber, J. L. Zarestky, D. J. Singh, A. S. Sefat and M. D. Lumsden, Competing magnetic ground states in nonsuperconducting Ba(Fe1−xCrx)2As2 as seen via neutron diffraction, Phys. Rev. B83, 060509(R) (2011), doi:10.1103/PhysRevB.83.060509

  36. [37]

    K. A. Filsinger, W. Schnelle, P. Adler, G. H. Fecher, M. Reehuis, A. Hoser, J.-U. Hoffmann, P. Werner, M. Greenblatt and C. Felser,Antiferromagnetic structure and electronic properties of BaCr2As2 and BaCrFeAs2, Physical Review B95(18), 184414 (2017), doi:10.1103/PhysRevB.95.184414

  37. [38]

    Q. Zou, M. Fu, Z. Wu, L. Li, D. S. Parker, A. S. Sefat and Z. Gai,Competitive and cooperative electronic states in Ba(Fe1−xTx)2As2 with T = Co, Ni, Cr, npj Quantum Materials 6(1), 1 (2021), doi:10.1038/s41535-021-00385-8

  38. [39]

    D. Gong, T. Xie, R. Zhang, J. Birk, C. Niedermayer, F. Han, S. H. Lapidus, P. Dai, S. Li and H. Luo, Doping effects of cr on the physical properties of BaFe1.9−xNi0.1CrxAs2, Phys. Rev. B 98, 014512 (2018), doi:10.1103/PhysRevB.98.014512

  39. [40]

    Zhang, D

    R. Zhang, D. Gong, X. Lu, S. Li, M. Laver, C. Niedermayer, S. Danilkin, G. Deng, P. Dai and H. Luo,Doping evolution of antiferromagnetism and transport properties in nonsuperconducting BaFe2−2xNixCrxAs2, Phys. Rev. B 91, 094506 (2015), doi:10.1103/PhysRevB.91.094506

  40. [41]

    D. Gong, M. Yi, M. Wang, T. Xie, W. Zhang, S. Danilkin, G. Deng, X. Liu, J. T. Park, K. Ikeuchi, K. Kamazawa, S.-K. Moet al., Nematic fluctuations in the non- superconducting iron pnictide BaFe1.9−xNi0.1CrxAs2, Frontiers in Physics10 (2022), doi:10.3389/fphy.2022.886459

  41. [42]

    Zhang, Y

    W. Zhang, Y. Wei, T. Xie, Z. Liu, D. Gong, X. Ma, D. Hu, P. Čermák, A. Schneidewind, G. Tucker, S. Meng, Z. Huesges et al., Unconventional antiferromagnetic quantum critical point in Ba(Fe0.97Cr0.03)2(As1−xPx)2, Phys. Rev. Lett. 122, 037001 (2019), doi:10.1103/PhysRevLett.122.037001

  42. [43]

    D. S. Inosov, G. Friemel, J. T. Park, A. C. Walters, Y. Texier, Y. Laplace, J. Bobroff, V. Hinkov, D. L. Sun, Y. Liu, R. Khasanov, K. Sedlaket al., Possible realization of an antiferromagnetic griffiths phase in Ba(Fe1−xMnx)2As2, Phys. Rev. B87, 224425 (2013), doi:10.1103/PhysRevB.87.224425

  43. [44]

    S. J. Li, D. Zhao, S. Wang, S. T. Cui, N. Z. Wang, J. Li, D. W. Song, B. L. Kang, L. X. Zheng, L. P. Nie, Z. M. Wu, Y. B. Zhou et al., Emergent spin- glass state in the doped hund’s metal CsFe2As2, Phys. Rev. B 107, 115144 (2023), doi:10.1103/PhysRevB.107.115144. 15 REFERENCES REFERENCES

  44. [45]

    C. Liu, G. D. Samolyuk, Y. Lee, N. Ni, T. Kondo, A. F. Santander-Syro, S. L. Bud’ko, J.L.McChesney, E.Rotenberg, T.Valla, A.V.Fedorov, P.C.Canfield et al., K-doping dependence of the fermi surface of the iron-arsenic Ba1−xKxFe2As2 superconductor using angle-resolved photoemission spectroscopy, Phys. Rev. Lett.101, 177005 (2008), doi:10.1103/PhysRevLett.101.177005

  45. [46]

    K. M. Stadler, G. Kotliar, S.-S. B. Lee, A. Weichselbaum and J. von Delft, Differentiating Hund from Mott physics in a three-band Hubbard-Hund model: Temperature dependence of spectral, transport, and thermodynamic properties , Physical Review B104(11), 115107 (2021), doi:10.1103/PhysRevB.104.115107

  46. [47]

    T. M. Garitezi, C. Adriano, P. F. S. Rosa, E. M. Bittar, L. Bufaiçal, R. L. d. Almeida, E. Granado, T. Grant, Z. Fisk, M. A. Avila, R. A. Ribeiro, P. L. Kuhns et al., Synthesis and Characterization of BaFe2As2 Single Crystals Grown by In-flux Technique, Brazilian Journal of Physics43(4), 223 (2013), doi:10.1007/s13538-013- 0144-z

  47. [48]

    Haule, C.-H

    K. Haule, C.-H. Yee and K. Kim,Dynamical mean-field theory within the full-potential methods: Electronic structure of CeIrIn5, CeCoIn5, and CeRhIn5, Phys. Rev. B81, 195107 (2010), doi:10.1103/PhysRevB.81.195107

  48. [49]

    J. P. Perdew, K. Burke and M. Ernzerhof,Generalized gradient approximation made simple, Phys. Rev. Lett.77, 3865 (1996), doi:10.1103/PhysRevLett.77.3865

  49. [50]

    Blaha, G

    P. Blaha, G. K. H. Madsen, D. Kvasnicka and J. Luitz, WIEN2K, An Augmented Plane Wave + Local Orbitals Program for Calculating Crystal Properties, Karlheinz Schwarz, Techn. Universität Wien, Austria (2001)

  50. [51]

    Haule, Quantum monte carlo impurity solver for cluster dynamical mean-field theory and electronic structure calculations with adjustable cluster base, Phys

    K. Haule, Quantum monte carlo impurity solver for cluster dynamical mean-field theory and electronic structure calculations with adjustable cluster base, Phys. Rev. B 75, 155113 (2007), doi:10.1103/PhysRevB.75.155113

  51. [52]

    V. I. Anisimov, F. Aryasetiawan and A. I. Lichtenstein,First-principles calculations of the electronic structure and spectra of strongly correlated systems: the lda+ u method, Journal of Physics: Condensed Matter9(4), 767 (1997), doi:10.1088/0953- 8984/9/4/002

  52. [53]

    Fuglsang Jensen, V

    M. Fuglsang Jensen, V. Brouet, E. Papalazarou, A. Nicolaou, A. Taleb-Ibrahimi, P. Le Fèvre, F. Bertran, A. Forget and D. Colson,Angle-resolved photoemission study of the role of nesting and orbital orderings in the antiferromagnetic phase of BaFe2As2, Physical Review B84(1), 014509 (2011), doi:10.1103/PhysRevB.84.014509

  53. [54]

    Brouet, M

    V. Brouet, M. F. Jensen, P.-H. Lin, A. Taleb-Ibrahimi, P. Le Fèvre, F. Bertran, C.-H. Lin, W. Ku, A. Forget and D. Colson,Impact of the two Fe unit cell on the electronic structure measured by ARPES in iron pnictides, Physical Review B 86(7), 075123 (2012), doi:10.1103/PhysRevB.86.075123

  54. [55]

    M. Yi, Y. Zhang, Z.-X. Shen and D. Lu,Role of the orbital degree of freedom in iron- based superconductors, npj Quantum Materials2(1), 57 (2017), doi:10.1038/s41535- 017-0059-y

  55. [56]

    H. Pfau, C. R. Rotundu, J. C. Palmstrom, S. D. Chen, M. Hashimoto, D. Lu, A. F. Kemper, I.R.FisherandZ.-X.Shen, Detailed band structure of twinned and detwinned BaFe2As2 studied with angle-resolved photoemission spectroscopy, Phys. Rev. B 99, 035118 (2019), doi:10.1103/PhysRevB.99.035118. 16 REFERENCES REFERENCES

  56. [57]

    Zhang, F

    Y. Zhang, F. Chen, C. He, B. Zhou, B. P. Xie, C. Fang, W. F. Tsai, X. H. Chen, H. Hayashi, J. Jiang, H. Iwasawa, K. Shimadaet al., Orbital characters of bands in the iron-based superconductor BaFe1.85Co0.15As2, Phys. Rev. B83(5), 054510 (2011), doi:10.1103/PhysRevB.83.054510

  57. [58]

    A. G. de Figueiredo, M. R. Cantarino, W. R. da Silva Neto, K. R. Pakuszewski, R. Grossi, D. S. Christovam, J. C. Souza, M. M. Piva, G. S. Freitas, P. G. Pagliuso, C. Adriano and F. A. Garcia, Orbital localization and the role of the fe and as 4p orbitals in BaFe2As2 probed by xanes, Phys. Rev. B 105, 045130 (2022), doi:10.1103/PhysRevB.105.045130

  58. [59]

    J. A. Sobota, Y. He and Z.-X. Shen, Angle-resolved photoemission studies of quantum materials , Reviews of Modern Physics 93(2), 025006 (2021), doi:10.1103/RevModPhys.93.025006

  59. [60]

    Kurleto and J

    R. Kurleto and J. Fink,About two-dimensional fits for the analysis of the scattering rates and renormalization functions from angle-resolved photoelectron spectroscopy data, Journal of Electron Spectroscopy and Related Phenomena253, 147127 (2021), doi:10.1016/j.elspec.2021.147127

  60. [61]

    J. Fink, E. D. L. Rienks, M. Yao, R. Kurleto, J. Bannies, S. Aswartham, I. Morozov, S. Wurmehl, T. Wolf, F. Hardy, C. Meingast, H. S. Jeevanet al., Linkage between scattering rates and superconductivity in doped ferropnictides, Physical Review B 103(15), 155119 (2021), doi:10.1103/PhysRevB.103.155119

  61. [62]

    J. Fink, E. D. L. Rienks, S. Thirupathaiah, J. Nayak, A. van Roekeghem, S. Biermann, T. Wolf, P. Adelmann, H. S. Jeevan, P. Gegenwart, S. Wurmehl, C. Felseret al., Experimental evidence for importance of Hund’s exchange interaction for incoherence of charge carriers in iron-based superconductors, Phys. Rev. B 95, 144513 (2017), doi:10.1103/PhysRevB.95.144513

  62. [63]

    Z. P. Yin, K. Haule and G. Kotliar, Fractional power-law behavior and its origin in iron-chalcogenide and ruthenate superconductors: Insights from first-principles calculations, Physical Review B 86(19), 195141 (2012), doi:10.1103/PhysRevB.86.195141

  63. [64]

    L.FanfarilloandE.Bascones, Electronic correlations in Hund metals, PhysicalReview B 92(7), 075136 (2015), doi:10.1103/PhysRevB.92.075136

  64. [65]

    M. Xu, J. Schmidt, E. Gati, L. Xiang, W. R. Meier, V. G. Kogan, S. L. Bud’ko and P. C. Canfield,Superconductivity and phase diagrams of CaK(Fe1−xMnx)4As4 single crystals, Phys. Rev. B105, 214526 (2022), doi:10.1103/PhysRevB.105.214526

  65. [66]

    M. Xu, J. Schmidt, M. A. Tanatar, R. Prozorov, S. L. Bud’ko and P. C. Canfield, Superconductivity and magnetic and transport properties of single-crystalline CaK (Fe1−xCrx)4As4, Phys. Rev. B 107, 134511 (2023), doi:10.1103/PhysRevB.107.134511

  66. [67]

    Crispino, P

    M. Crispino, P. V. Arribi, A. Shukla, F. Hardy, A.-A. Haghighirad, T. Wolf, R. Heid, C. Meingast, T. Gorni, A. Avella and L. d. Medici,Paradigm for finding d-electron heavy fermions: the case of Cr-doped CsFe2As2, arXiv (arXiv:2312.06511) (2023), doi:10.48550/arXiv.2312.06511, 2312.06511[cond-mat]. 17 REFERENCES REFERENCES

  67. [68]

    Graser, A

    S. Graser, A. F. Kemper, T. A. Maier, H.-P. Cheng, P. J. Hirschfeld and D. J. Scalapino, Spin fluctuations and superconductivity in a three- dimensional tight-binding model for BaFe2As2, Phys. Rev. B 81, 214503 (2010), doi:10.1103/PhysRevB.81.214503. 18