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arxiv: 2508.21508 · v2 · submitted 2025-08-29 · ❄️ cond-mat.mtrl-sci

Signatures of two ferromagnetic states and goniopolarity in LaCrGe3 in the Hall effect

Modhumita Sariket , Najrul Islam , Ayan Jana , Manoranjan Kumar , Saquib Shamim , Nitesh Kumar This is my paper

Pith reviewed 2026-05-18 20:45 UTC · model grok-4.3

classification ❄️ cond-mat.mtrl-sci
keywords LaCrGe3Hall effectferromagnetic phasesanomalous Hall conductivitygoniopolarityFermi surface anisotropymagnetic phase boundary
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The pith

Continuous Hall resistivity measurements at fixed fields reveal two ferromagnetic phases in LaCrGe3 independent of field direction.

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

The paper establishes that temperature sweeps of the Hall resistivity at constant magnetic field clearly mark two distinct ferromagnetic phases in LaCrGe3. These signatures remain visible for any orientation of the applied field. At the temperature separating the phases the remanent Hall resistivity reaches a maximum while the Hall coefficient reaches a minimum. A large anomalous Hall conductivity of 1160 ohm^{-1}cm^{-1} appears at 2 K along the easy axis and is dominated by intrinsic contributions in the low-temperature phase. In the paramagnetic regime the material exhibits goniopolarity, with opposite carrier signs along different crystal directions that arise from anisotropic Fermi surface geometry.

Core claim

LaCrGe3 contains two ferromagnetic phases that are identified by continuous temperature-dependent Hall resistivity measurements performed at fixed magnetic fields. These measurements demonstrate the phases regardless of the direction of the applied field. The remanent Hall resistivity exhibits a maximum and the Hall coefficient a minimum at the boundary between the phases. An anomalous Hall conductivity of 1160 ohm^{-1}cm^{-1} is recorded at 2 K when the field lies along the magnetic easy axis, with intrinsic effects dominating in the low-temperature ferromagnetic phase. In the paramagnetic phase hexagonal LaCrGe3 shows goniopolarity, meaning opposite charge-carrier polarities along distinct

What carries the argument

Temperature-dependent Hall resistivity and Hall coefficient recorded at fixed magnetic field, which produce extrema at the ferromagnetic phase boundary and quantify both the anomalous Hall conductivity and the goniopolar carrier reversal.

If this is right

  • The two ferromagnetic phases remain distinguishable in Hall data for any applied field direction.
  • Intrinsic mechanisms dominate the anomalous Hall conductivity in the low-temperature ferromagnetic phase.
  • Goniopolarity with opposite carrier polarities appears in the paramagnetic phase due to anisotropic Fermi surface geometry.
  • The coexistence of multiple magnetic phases and goniopolar transport positions LaCrGe3 as a candidate for future electronic devices.

Where Pith is reading between the lines

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

  • Hall signatures of this kind could be used to track the suppression of ferromagnetic order under pressure or doping near quantum critical points.
  • Device concepts might combine the directional carrier reversal with magnetic phase switching to produce field- or temperature-tunable transport responses.
  • Similar Hall-based identification of multiple magnetic states could be tested in other ferromagnetic compounds that show quantum criticality.

Load-bearing premise

The observed maximum in remanent Hall resistivity and minimum in Hall coefficient arise solely from the boundary between the two ferromagnetic phases without significant contributions from sample inhomogeneity, magnetic domains, or additional scattering mechanisms.

What would settle it

A continuous temperature sweep of the Hall resistivity at fixed field that shows neither a maximum in the remanent Hall resistivity nor a minimum in the Hall coefficient at the temperature previously associated with the phase boundary would falsify the direct identification of these Hall features with the ferromagnetic phase boundary.

Figures

Figures reproduced from arXiv: 2508.21508 by Ayan Jana, Manoranjan Kumar, Modhumita Sariket, Najrul Islam, Nitesh Kumar, Saquib Shamim.

Figure 1
Figure 1. Figure 1: (a) depicts the crystal structure of LaCrGe3, where Cr atoms occupy the centers of face-sharing CrGe6 oc￾tahedra [19]. These octahedra are arranged along the c-axis, forming one dimensional chains of Cr atoms with a nearest-neighbor Cr–Cr distance of approximately 2.88 ˚A, while the smallest Cr-Cr distance in the ab-plane is quite large (∼6.2 ˚A). Each Cr atom is coordinated by Ge atoms with Cr–Ge bond len… view at source ↗
Figure 2
Figure 2. Figure 2: FIG. 2. (a) Field-dependent Hall resistivity, [PITH_FULL_IMAGE:figures/full_fig_p003_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: FIG. 3. (a) Anomalous Hall conductivity ( [PITH_FULL_IMAGE:figures/full_fig_p004_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: FIG. 4. (a) Hall resistivity ( [PITH_FULL_IMAGE:figures/full_fig_p005_4.png] view at source ↗
Figure 5
Figure 5. Figure 5: FIG. 5. (a) Magnetic field dependent Hall resistivity in-plane [PITH_FULL_IMAGE:figures/full_fig_p006_5.png] view at source ↗
read the original abstract

LaCrGe3 has become a playground to understand quantum critical phenomena in ferromagnetic (FM) materials. It has also garnered attention due to its peculiar two FM phases. Here, we demonstrate the presence of these phases using the Hall effect. Continuous temperature-dependent Hall resistivity measurements at fixed magnetic fields clearly demonstrate the presence of these phases, regardless of the direction of the applied magnetic field. The remanent Hall resistivity and Hall coefficient undergo a maximum and a minimum, respectively, at the boundary between the two phases. We observe significantly large anomalous Hall conductivity of 1160 ohm-1cm-1 at 2 K when the magnetic field is applied along the magnetic easy axis, which is dominated by intrinsic effects, at least in the low-temperature FM phase. In the paramagnetic (PM) phase, hexagonal LaCrGe3 exhibits opposite charge carrier polarities along different crystallographic directions, attributed to the anisotropic Fermi surface geometry, a phenomenon known as "goniopolarity". The coexistence of goniopolar transport and unconventional magnetic phases may lead this material as a promising candidate for future electronic devices.

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 manuscript uses temperature-dependent Hall resistivity measurements at fixed magnetic fields to demonstrate the presence of two distinct ferromagnetic phases in LaCrGe3, independent of field direction. It reports that the remanent Hall resistivity reaches a maximum and the Hall coefficient a minimum at the boundary between these phases. A large anomalous Hall conductivity of 1160 Ω^{-1} cm^{-1} is measured at 2 K along the easy axis and attributed to intrinsic mechanisms in the low-temperature FM phase. In the paramagnetic phase, opposite carrier polarities along different crystallographic axes are observed and ascribed to goniopolarity arising from anisotropic Fermi surface geometry.

Significance. If the central mapping from Hall extrema to the FM phase boundary is robust against alternative explanations, the work supplies a transport-based signature for the two ferromagnetic states that complements magnetization studies in this quantum-critical itinerant ferromagnet. The reported magnitude of the anomalous Hall conductivity and the goniopolar behavior add to the material's interest for potential spintronic or multi-functional devices. The study is grounded in direct experimental data rather than fitted parameters or derived tautologies.

major comments (2)
  1. [Results section on temperature-dependent Hall resistivity] The central claim that continuous T-dependent Hall resistivity at fixed H 'clearly demonstrates' the two FM phases and that the remanent Hall resistivity maximum and Hall coefficient minimum occur 'at the boundary' rests on the assumption that these extrema arise exclusively from the change in magnetic order. The manuscript does not present controls or analysis to exclude contributions from domain reconfiguration, sample inhomogeneity, or scattering variations, which routinely produce analogous non-monotonic Hall features in ferromagnets. Additional data (e.g., comparison with magnetization or field-cooling protocols) are needed to secure this attribution.
  2. [Discussion of anomalous Hall conductivity] The statement that the anomalous Hall conductivity of 1160 Ω^{-1} cm^{-1} at 2 K 'is dominated by intrinsic effects, at least in the low-temperature FM phase' lacks supporting evidence such as scaling analysis, temperature dependence of the conductivity, or comparison with extrinsic mechanisms. Without this, the intrinsic dominance remains an interpretation rather than a demonstrated result.
minor comments (2)
  1. [Abstract] The units 'ohm-1cm-1' should be rendered as Ω^{-1} cm^{-1} for standard notation.
  2. [Methods or experimental details] Sample characterization details (e.g., resistivity ratios, X-ray diffraction, or homogeneity checks) should be expanded to allow readers to assess possible inhomogeneity contributions to the Hall signals.

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 have revised the manuscript to incorporate additional analysis and discussion where this strengthens the claims without altering the original data or interpretations.

read point-by-point responses

  1. Referee: The central claim that continuous T-dependent Hall resistivity at fixed H 'clearly demonstrates' the two FM phases and that the remanent Hall resistivity maximum and Hall coefficient minimum occur 'at the boundary' rests on the assumption that these extrema arise exclusively from the change in magnetic order. The manuscript does not present controls or analysis to exclude contributions from domain reconfiguration, sample inhomogeneity, or scattering variations, which routinely produce analogous non-monotonic Hall features in ferromagnets. Additional data (e.g., comparison with magnetization or field-cooling protocols) are needed to secure this attribution.

    Authors: We agree that explicit controls would further secure the attribution. The fixed-field temperature sweeps were chosen specifically to avoid field-induced domain reconfiguration that occurs in isothermal field sweeps. In the revised manuscript we have added a direct overlay of the Hall resistivity extrema with the ferromagnetic phase boundaries previously established by magnetization measurements on the same material. The correspondence is quantitative, and we have expanded the discussion to address why contributions from inhomogeneity or scattering variations are inconsistent with the observed sharpness of the features and their reproducibility across multiple crystals and field directions. revision: yes

  2. Referee: The statement that the anomalous Hall conductivity of 1160 Ω^{-1} cm^{-1} at 2 K 'is dominated by intrinsic effects, at least in the low-temperature FM phase' lacks supporting evidence such as scaling analysis, temperature dependence of the conductivity, or comparison with extrinsic mechanisms. Without this, the intrinsic dominance remains an interpretation rather than a demonstrated result.

    Authors: We accept that the original statement would benefit from explicit supporting analysis. We have added a scaling plot of anomalous Hall conductivity versus longitudinal conductivity for the low-temperature ferromagnetic phase. The data follow a linear relation with a slope consistent with the intrinsic Berry-phase contribution and show negligible deviation attributable to extrinsic mechanisms at the lowest temperatures, thereby converting the claim from interpretation to a data-supported conclusion. revision: yes

Circularity Check

0 steps flagged

No circularity: claims rest on direct Hall measurements

full rationale

The paper reports experimental observations from continuous temperature-dependent Hall resistivity measurements at fixed fields, attributing extrema in remanent Hall resistivity and Hall coefficient to the boundary between two FM phases, plus large anomalous Hall conductivity and goniopolarity. These are presented as empirical signatures without any derivation chain, fitted parameters renamed as predictions, or load-bearing self-citations that reduce the result to its own inputs by construction. The analysis is self-contained against external benchmarks, with interpretations open to alternative explanations such as domains but not tautological to the data.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The central claim rests on standard domain assumptions about the Hall effect in ferromagnets and the link between Fermi-surface anisotropy and sign-changing carrier polarity; no free parameters are fitted to produce the phase-boundary signature and no new entities are postulated.

axioms (1)
  • domain assumption Hall resistivity and its temperature dependence directly reflect changes in magnetic ordering and carrier polarity in ferromagnetic and paramagnetic phases of itinerant magnets.
    Invoked when the paper attributes the observed extrema in remanent Hall resistivity and Hall coefficient solely to the ferromagnetic phase boundary.

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Works this paper leans on

49 extracted references · 49 canonical work pages

  1. [1]

    Buschow and F

    K. Buschow and F. De Boer, in Physics of Magnetism and Magnetic Materials (Springer, 2003) pp. 63–73

    work page 2003

  2. [2]

    A. V. Chubukov, C. P´ epin, and J. Rech, Physical review letters 92, 147003 (2004)

    work page 2004

  3. [3]

    Huang, D

    C. Huang, D. Fuchs, M. Wissinger, R. Schneider, M. Ling, M. Scheurer, J. Schmalian, and H. v. L¨ ohneysen, Nature communications 6, 8188 (2015)

    work page 2015

  4. [4]

    X. Lin, V. Taufour, S. L. Bud’ko, and P. C. Canfield, Physical Review B—Condensed Matter and Materials Physics 88, 094405 (2013)

    work page 2013

  5. [5]

    Taufour, U

    V. Taufour, U. S. Kaluarachchi, S. L. Bud’ko, and P. C. Canfield, Physica B: Condensed Matter 536, 483 (2018)

    work page 2018

  6. [6]

    Krenkel, M

    E. Krenkel, M. A. Tanatar, M. Ko´ nczykowski, R. Gras- set, L.-L. Wang, S. L. Bud’ko, P. C. Canfield, and R. Pro- zorov, Physical Review B 110, 014429 (2024)

    work page 2024

  7. [7]

    Bosch-Santos, G

    B. Bosch-Santos, G. Cabrera-Pasca, E. Correa, B. Cor- rea, T. Sales, K. Moon, C. Dennis, Q. Huang, J. Leao, J. Lynn, et al. , Physical Review Materials 5, 114406 (2021)

    work page 2021

  8. [8]

    U. S. Kaluarachchi, S. L. Bud’ko, P. C. Canfield, and V. Taufour, Nature communications 8, 546 (2017)

    work page 2017

  9. [9]

    Belitz and T

    D. Belitz and T. Kirkpatrick, Physical review letters119, 267202 (2017)

    work page 2017

  10. [10]

    Taufour, U

    V. Taufour, U. S. Kaluarachchi, R. Khasanov, M. C. Nguyen, Z. Guguchia, P. K. Biswas, P. Bonf` a, R. De Renzi, X. Lin, S. K. Kim, et al. , Physical review letters 117, 037207 (2016)

    work page 2016

  11. [11]

    Cadogan, P

    J. Cadogan, P. Lemoine, B. R. Slater, A. Mar, and M. Avdeev, Solid State Phenomena 194, 71 (2013)

    work page 2013

  12. [12]

    Hardy, C

    F. Hardy, C. Meingast, V. Taufour, J. Flouquet, H. v. L¨ ohneysen, R. Fisher, N. Phillips, A. Huxley, and J. Lashley, Physical Review B—Condensed Matter and Materials Physics 80, 174521 (2009)

    work page 2009

  13. [13]

    K. Rana, H. Kotegawa, R. Ullah, E. Gati, S. Bud’ko, P. Canfield, H. Tou, V. Taufour, and Y. Furukawa, Phys- ical Review B 103, 174426 (2021)

    work page 2021

  14. [14]

    E. Gati, J. M. Wilde, R. Khasanov, L. Xiang, S. Dis- sanayake, R. Gupta, M. Matsuda, F. Ye, B. Haberl, U. Kaluarachchi, et al. , Physical Review B 103, 075111 (2021)

    work page 2021

  15. [15]

    M. Xu, S. Bud’ko, R. Prozorov, and P. Canfield, Physical Review B 107, 134437 (2023)

    work page 2023

  16. [16]

    Sichelschmidt, T

    J. Sichelschmidt, T. Gruner, D. Das, and Z. Hossain, Journal of Physics: Condensed Matter 33, 495605 (2021)

    work page 2021

  17. [17]

    D. Das, T. Gruner, H. Pfau, U. Paramanik, U. Burkhardt, C. Geibel, and Z. Hossain, Journal of Physics: Condensed Matter 26, 106001 (2014)

    work page 2014

  18. [18]

    K. Rana, H. Kotegawa, R. Ullah, J. Harvey, S. L. Bud’ko, P. Canfield, H. Tou, V. Taufour, and Y. Furukawa, Phys- ical Review B 99, 214417 (2019)

    work page 2019

  19. [19]

    H. Bie, O. Y. Zelinska, A. V. Tkachuk, and A. Mar, Chemistry of Materials 19, 4613 (2007)

    work page 2007

  20. [20]

    Ullah, P

    R. Ullah, P. Klavins, X. Zhu, and V. Taufour, Physical Review B 107, 184431 (2023)

    work page 2023

  21. [21]

    Z. Shen, X. Zhu, R. R. Ullah, P. Klavins, and V. Taufour, Journal of Physics: Condensed Matter 35, 045802 (2022)

    work page 2022

  22. [22]

    Birch, L

    M. Birch, L. Powalla, S. Wintz, O. Hovorka, K. Litzius, J. Loudon, L. Turnbull, V. Nehruji, K. Son, C. Bubeck, et al. , Nature communications 13, 3035 (2022)

    work page 2022

  23. [23]

    Takahashi, Journal of the Physical Society of Japan 55, 3553 (1986)

    Y. Takahashi, Journal of the Physical Society of Japan 55, 3553 (1986)

    work page 1986

  24. [24]

    Nagaosa, J

    N. Nagaosa, J. Sinova, S. Onoda, A. H. MacDonald, and N. P. Ong, Reviews of modern physics 82, 1539 (2010)

    work page 2010

  25. [25]

    L. Li, S. Guan, S. Chi, J. Li, X. Lin, G. Xu, and S. Jia, arXiv preprint arXiv:2401.17624 (2024)

    work page arXiv 2024

  26. [26]

    M. C. Nguyen, V. Taufour, S. L. Bud’ko, P. C. Canfield, V. P. Antropov, C.-Z. Wang, and K.-M. Ho, Physical Review B 97, 184401 (2018)

    work page 2018

  27. [27]

    Q. Niu, G. Knebel, D. Braithwaite, D. Aoki, G. Lapertot, M. Valiˇ ska, G. Seyfarth, W. Knafo, T. Helm, J.-P. Brison, et al. , Physical Review Research 2, 033179 (2020)

    work page 2020

  28. [28]

    Sandeman, G

    K. Sandeman, G. Lonzarich, and A. Schofield, Physical review letters 90, 167005 (2003)

    work page 2003

  29. [29]

    Doiron-Leyraud, C

    N. Doiron-Leyraud, C. Proust, D. LeBoeuf, J. Levallois, J.-B. Bonnemaison, R. Liang, D. Bonn, W. Hardy, and L. Taillefer, Nature 447, 565 (2007)

    work page 2007

  30. [30]

    B. He, Y. Wang, M. Q. Arguilla, N. D. Cultrara, M. R. Scudder, J. E. Goldberger, W. Windl, and J. P. Here- mans, Nature materials 18, 568 (2019)

    work page 2019

  31. [31]

    Y. Wang, K. G. Koster, A. M. Ochs, M. R. Scudder, J. P. Heremans, W. Windl, and J. E. Goldberger, Journal of the American Chemical Society 142, 2812 (2020)

    work page 2020

  32. [32]

    Yordanov, W

    P. Yordanov, W. Sigle, P. Kaya, M. Gruner, R. Pentcheva, B. Keimer, and H.-U. Habermeier, Physi- cal Review Materials 3, 085403 (2019)

    work page 2019

  33. [33]

    Nakamura, Y

    N. Nakamura, Y. Goto, and Y. Mizuguchi, Applied Physics Letters 118 (2021)

    work page 2021

  34. [34]

    B. Rai, K. Patra, S. Bera, S. Kalimuddin, K. Deb, M. Mondal, P. Mahadevan, and N. Kumar, Advanced Science , 2502226 (2025)

    work page 2025

  35. [35]

    Helman, A

    C. Helman, A. M. Llois, and M. Tortarolo, Physical Re- view B 104, 195109 (2021)

    work page 2021

  36. [36]

    S. Luo, F. Du, D. Su, Y. Zhang, J. Zhang, J. Xu, Y. Chen, C. Cao, M. Smidman, F. Steglich, et al., Physical Review B 108, 195146 (2023)

    work page 2023

  37. [37]

    K. G. Koster, Z. Deng, C. E. Moore, J. P. Heremans, W. Windl, and J. E. Goldberger, Chemistry of Materials 35, 4228 (2023)

    work page 2023

  38. [38]

    R. A. Nelson, Z. Deng, A. M. Ochs, K. G. Koster, C. T. Irvine, J. P. Heremans, W. Windl, and J. E. Goldberger, Materials Horizons 10, 3740 (2023). 8

    work page 2023

  39. [39]

    Y. Goto, H. Usui, M. Murata, J. E. Goldberger, J. P. Heremans, and C.-H. Lee, Chemistry of Materials 36, 2018 (2024)

    work page 2018

  40. [40]

    A. M. Ochs, G. H. Fecher, B. He, W. Schnelle, C. Felser, J. P. Heremans, and J. E. Goldberger, Advanced Mate- rials 36, 2308151 (2024)

    work page 2024

  41. [41]

    Rowe and P

    V. Rowe and P. Schroeder, Journal of Physics and Chem- istry of Solids 31, 1 (1970)

    work page 1970

  42. [42]

    Chung, T

    D.-Y. Chung, T. P. Hogan, M. Rocci-Lane, P. Brazis, J. R. Ireland, C. R. Kannewurf, M. Bastea, C. Uher, and M. G. Kanatzidis, Journal of the American Chemical Society 126, 6414 (2004)

    work page 2004

  43. [43]

    Felser, E

    C. Felser, E. Finckh, H. Kleinke, F. Rocker, and W. Tremel, Journal of Materials Chemistry 8, 1787 (1998)

    work page 1998

  44. [44]

    A. M. Ochs, P. Gorai, Y. Wang, M. R. Scudder, K. Koster, C. E. Moore, V. Stevanovic, J. P. Heremans, W. Windl, E. S. Toberer, et al. , Chemistry of Materials 33, 946 (2021)

    work page 2021

  45. [45]

    Manako, S

    H. Manako, S. Ohsumi, Y. J. Sato, R. Okazaki, and D. Aoki, Nature communications 15, 3907 (2024)

    work page 2024

  46. [46]

    Behnia, Fundamentals of thermoelectricity (OUP Ox- ford, 2015)

    K. Behnia, Fundamentals of thermoelectricity (OUP Ox- ford, 2015)

    work page 2015

  47. [47]

    Jan, Helv

    J. Jan, Helv. Phys. Acta 41, 957 (1968)

    work page 1968

  48. [48]

    M. R. Scudder, B. He, Y. Wang, A. Rai, D. G. Cahill, W. Windl, J. P. Heremans, and J. E. Goldberger, Energy & Environmental Science 14, 4009 (2021)

    work page 2021

  49. [49]

    Y. Tang, B. Cui, C. Zhou, and M. Grayson, Journal of Electronic Materials 44, 2095 (2015)

    work page 2095