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arxiv: 2605.19445 · v1 · pith:2NPO2AK5new · submitted 2026-05-19 · ❄️ cond-mat.mtrl-sci

Zero-net-magnetization hybrid magnet

San-Dong Guo , Shi-Hao Zhang This is my paper

Pith reviewed 2026-05-20 04:29 UTC · model grok-4.3

classification ❄️ cond-mat.mtrl-sci
keywords zero-net-magnetization magnethybrid magnetheterojunctiontype-II band alignmentdoping-induced magnetizationPT-antiferromagnetcompensated ferrimagnetfirst-principles
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0 comments X

The pith

In zero-net-magnetization hybrid magnets built from heterojunctions, type-II band alignment causes only one carrier type to induce a net magnetic moment.

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

The paper proposes a new class of magnets assembled by stacking monolayers that are each zero-net-magnetization but linked by different symmetry relations in local regions. In the resulting heterojunctions that show type-II band alignment, adding electrons or holes breaks the compensation asymmetrically so that one doping direction produces a net moment while the other leaves the magnetization near zero. A reader would care because the base state carries no stray field yet can be switched into a magnetized state by simple carrier injection, which fits the requirements for dense and fast magnetic applications. The authors support the picture first with a tight-binding model of the PT-antiferromagnet plus fully compensated ferrimagnet case and then with explicit first-principles calculations on the Cr2C2S6/CrMoC2S6 stack under electric-field tuning.

Core claim

The authors establish that when a heterojunction hybrid magnet exhibits type-II band alignment, only one of electron doping and hole doping can induce a net magnetic moment while the other hardly generates any net magnetization. The system is formed by combining a PT-antiferromagnet monolayer with a fully compensated ferrimagnet monolayer so that magnetic atoms of opposite spin are partially coupled by P symmetry, by C/M symmetry, or without symmetry correlation. The proposal is checked first by constructing and solving a tight-binding model and then by performing first-principles calculations together with electric-field modulation on the concrete Cr2C2S6/CrMoC2S6 heterojunction.

What carries the argument

The type-II band alignment at the heterojunction between a PT-antiferromagnet and a fully compensated ferrimagnet that produces an asymmetric doping response.

If this is right

  • Only one carrier type produces a net moment while the opposite carrier type leaves the magnetization essentially zero.
  • The undoped heterojunction retains zero net magnetization from the compensating local moments.
  • The hybrid-magnet construction applies to three distinct classes of zero-net-magnetization monolayers.
  • Electric-field modulation can be used to tune the band alignment and doping response in the example material stack.

Where Pith is reading between the lines

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

  • Gate-voltage polarity could therefore select whether a net moment appears, offering a simple electrical control knob.
  • The same heterojunction strategy might be tried with altermagnet monolayers if type-II alignment can be engineered.
  • Realistic devices would need to test whether interlayer coupling violates the local-region approximation used in the model.

Load-bearing premise

Interactions between local regions can be neglected and the heterojunction reliably forms with type-II band alignment together with the stated symmetry properties of the monolayers.

What would settle it

Fabricate the Cr2C2S6/CrMoC2S6 heterojunction, measure its band alignment, and observe whether both electron and hole doping produce comparable net magnetic moments instead of the predicted strong asymmetry.

Figures

Figures reproduced from arXiv: 2605.19445 by San-Dong Guo, Shi-Hao Zhang.

Figure 2
Figure 2. Figure 2: FIG. 2. (Color online) (a): two zero-net-magnetization mag [PITH_FULL_IMAGE:figures/full_fig_p002_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: FIG. 3. (Color online) The energy bands obtained from min [PITH_FULL_IMAGE:figures/full_fig_p003_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: FIG. 4. (Color online) For Cr [PITH_FULL_IMAGE:figures/full_fig_p004_4.png] view at source ↗
Figure 5
Figure 5. Figure 5: FIG. 5. (Color online)For Cr [PITH_FULL_IMAGE:figures/full_fig_p005_5.png] view at source ↗
read the original abstract

Zero-net-magnetization magnets possess ultradense and ultrafast application potential, benefiting from their intrinsic zero stray field and terahertz dynamics characteristics. Herein, we propose the concept of zero-net-magnetization hybrid magnet, in which magnetic atoms with opposite spin polarization are partially coupled via spatial inversion ($P$) symmetry, partially via rotation/mirror ($C/M$) symmetry or partially without any symmetry correlation. From a local perspective and neglecting the interactions between local regions, hybrid magnet can be regarded as being composed of $PT$-antiferromagnet (possessing the combined symmetry ($PT$) of $P$ and time-reversal ($T$)), altermagnet, or fully compensated ferrimagnet. To realize hybrid magnet, we propose that such system can be constructed by forming heterojunction with three types of zero-net-magnetization magnetic monolayers. We mainly investigate the heterojunction composed of two kinds of zero-net-magnetization magnets, among which one type corresponds to fully compensated ferrimagnet. When heterojunction hybrid magnet exhibits a type-II band alignment, only one of electron doping and hole doping can induce a net magnetic moment, while the other hardly generates any net magnetization. Taking the heterojunction constructed by $PT$-antiferromagnet and fully compensated ferrimagnet as an example, we verify our proposal by means of the tight-binding (TB) model. Finally, taking the $\mathrm{Cr_2C_2S_6}$/$\mathrm{CrMoC_2S_6}$ heterojunction as an example, we perform first-principles calculations combined with electric field modulation to validate our TB model and theoretical proposal.

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 proposes the concept of a zero-net-magnetization hybrid magnet formed by heterojunctions of monolayers including PT-antiferromagnets and fully compensated ferrimagnets. Under type-II band alignment and a local-region approximation that neglects inter-region interactions, only one carrier type (electrons or holes) is predicted to induce a net magnetic moment while the other produces negligible magnetization; this is illustrated with a tight-binding model and validated via DFT plus electric-field modulation on the Cr₂C₂S₆/CrMoC₂S₆ heterojunction.

Significance. If the local approximation and type-II alignment hold in fabricated devices, the selective-doping mechanism would provide an electrically tunable route to net magnetization in zero-stray-field systems, with potential for terahertz spintronics. The explicit TB construction and concrete DFT example on specific monolayers constitute a strength, supplying falsifiable predictions and reproducible numerical support for the asymmetry claim.

major comments (2)
  1. [Abstract and proposal section] Abstract and the proposal section: the claim that 'only one of electron doping and hole doping can induce a net magnetic moment, while the other hardly generates any net magnetization' is load-bearing for the central result yet rests on the explicit assumption that interactions between local regions can be neglected. This is implemented by separate Hamiltonians in the TB model; the manuscript provides no estimate of the hybridization scale at the interface that would be required to preserve the selective localization.
  2. [DFT calculations on Cr₂C₂S₆/CrMoC₂S₆] DFT section on Cr₂C₂S₆/CrMoC₂S₆: the first-principles results assume the heterojunction interface maintains sufficient decoupling for the type-II alignment and symmetry properties to survive; no orbital-projected density of states or layer-resolved band analysis is shown to quantify possible mixing of magnetic-atom orbitals across layers, which could allow both doping signs to generate comparable net moments.
minor comments (2)
  1. [Introduction] The symmetry classification of hybrid magnets (PT-AFM, altermagnet, compensated ferrimagnet components) would benefit from an explicit table or figure summarizing the partial symmetry correlations.
  2. [Figures] Figure captions and axis labels in the TB and DFT plots should explicitly state the doping range and the criterion used to declare 'hardly generates any' net magnetization (e.g., moment threshold).

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the thorough review and valuable feedback on our manuscript proposing the zero-net-magnetization hybrid magnet. We address each major comment in detail below and indicate the revisions we plan to make.

read point-by-point responses

  1. Referee: [Abstract and proposal section] Abstract and the proposal section: the claim that 'only one of electron doping and hole doping can induce a net magnetic moment, while the other hardly generates any net magnetization' is load-bearing for the central result yet rests on the explicit assumption that interactions between local regions can be neglected. This is implemented by separate Hamiltonians in the TB model; the manuscript provides no estimate of the hybridization scale at the interface that would be required to preserve the selective localization.

    Authors: We concur that an estimate of the hybridization scale is necessary to support the validity of the local approximation used in our tight-binding model. The model separates the Hamiltonians for different regions to illustrate the selective doping effect under type-II alignment. In the revised manuscript, we will incorporate an analysis estimating the interface hybridization energy from the DFT results on the Cr₂C₂S₆/CrMoC₂S₆ system. This will show that the relevant hybridization is weak compared to the band offsets and doping energies, justifying the neglect of inter-region interactions for the proposed mechanism. revision: yes

  2. Referee: [DFT calculations on Cr₂C₂S₆/CrMoC₂S₆] DFT section on Cr₂C₂S₆/CrMoC₂S₆: the first-principles results assume the heterojunction interface maintains sufficient decoupling for the type-II alignment and symmetry properties to survive; no orbital-projected density of states or layer-resolved band analysis is shown to quantify possible mixing of magnetic-atom orbitals across layers, which could allow both doping signs to generate comparable net moments.

    Authors: The referee correctly points out that additional evidence for minimal orbital mixing would strengthen the DFT validation. We will revise the manuscript to include orbital-projected density of states and layer-resolved band structures for the heterojunction. These analyses will confirm limited hybridization between the magnetic atoms in different layers, preserving the type-II alignment and the distinct symmetry properties that underpin the asymmetric response to electron and hole doping. revision: yes

Circularity Check

0 steps flagged

No significant circularity; derivation self-contained via explicit modeling

full rationale

The paper proposes the hybrid magnet concept under a local-region approximation that neglects inter-region interactions, then demonstrates the selective doping effect for type-II alignment through an explicit tight-binding model (separate Hamiltonians for each monolayer) and independent first-principles DFT on the concrete Cr2C2S6/CrMoC2S6 heterojunction. The selective net-moment induction follows as a calculable consequence of the band alignment and symmetry properties within those models rather than reducing by definition or by renaming a fitted input. No load-bearing self-citations, uniqueness theorems, or ansatzes imported from prior author work appear in the derivation chain. The verification steps are independent and falsifiable outside the proposal itself.

Axiom & Free-Parameter Ledger

0 free parameters · 2 axioms · 1 invented entities

The central claim rests on standard symmetry classifications of magnets and the assumption of negligible inter-region interactions; no new free parameters are explicitly fitted in the abstract, but the TB model likely introduces hopping or exchange parameters.

axioms (2)
  • domain assumption Magnetic atoms with opposite spin polarization can be partially coupled via P, C/M, or no symmetry.
    Invoked in the definition of the hybrid magnet from a local perspective.
  • ad hoc to paper Interactions between local regions can be neglected.
    Explicitly stated as the basis for treating the hybrid as composed of PT-AFM, altermagnet, or compensated ferrimagnet.
invented entities (1)
  • zero-net-magnetization hybrid magnet no independent evidence
    purpose: New class of magnet combining different symmetry couplings for selective doping response.
    Introduced as the core proposal; no independent experimental evidence provided.

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Reference graph

Works this paper leans on

45 extracted references · 45 canonical work pages · 2 internal anchors

  1. [1]

    Hu, Half-metallic antiferromagnet as a prospective material for spintronics, Adv

    X. Hu, Half-metallic antiferromagnet as a prospective material for spintronics, Adv. Mater.24, 294 (2012)

    work page 2012

  2. [2]

    Jungwirth, J

    T. Jungwirth, J. Sinova, A. Manchon, X. Marti, J. Wun- derlich and C. Felser, The multiple directions of antifer- romagnetic spintronics, Nat. Phys.14, 200 (2018)

    work page 2018

  3. [3]

    Z. Guo, X. Wang, W. Wang, G. Zhang, X. Zhou and Z. Cheng, Spin-Polarized Antiferromagnets for Spintronics, Adv. Mater.37, 2505779 (2025)

    work page 2025

  4. [4]

    ˘Smejkal, J

    L. ˘Smejkal, J. Sinova and T. Jungwirth, Beyond conven- tional ferromagnetism and antiferromagnetism: A phase with nonrelativistic spin and crystal rotation symmetry, Phys. Rev. X12, 031042 (2022)

    work page 2022

  5. [5]

    Mazin, Altermagnetism-a new punch line of fundamen- tal magnetism, Phys

    I. Mazin, Altermagnetism-a new punch line of fundamen- tal magnetism, Phys. Rev. X12, 040002 (2022)

    work page 2022

  6. [6]

    Y. Liu, S. D. Guo, Y. Li and C. C. Liu, Two-dimensional fully-compensated Ferrimagnetism, Phys. Rev. Lett. 134, 116703 (2025)

    work page 2025

  7. [7]

    S. D. Guo, Valley polarization in two-dimensional zero- net-magnetization magnets, Appl. Phys. Lett.126, 080502 (2025)

    work page 2025

  8. [8]

    S. D. Guo, Q. Luo, S. H. Zhang and P. Jiang, Exter- nal field induced transition from altermagnetic metal to fully compensated ferrimagnetic metal in monolayer Cr2O, Phys. Rev. B113, 064408 (2026)

    work page 2026

  9. [9]

    X. Chen, J. Ren, Y. Zhu, Y. Yu, A. Zhang, P. Liu, J. Li, Y. Liu, C. Li and Q. Liu, Enumeration and representa tion theory of spin space groups, Phys. Rev. X14, 031038 (2024)

    work page 2024

  10. [10]

    L. Bai, W. Feng, S. Liu, L. ˘Smejkal, Y. Mokrousov, and Y. Yao, Altermagnetism: Exploring New Frontiers in Magnetism and Spintronics, Adv. Funct. Mater.34, 2409327 (2024)

    work page 2024

  11. [11]

    H.-Y. Ma, M. L. Hu, N. N. Li, J. P. Liu, W. Yao, J. F. Jia and J. W. Liu, Multifunctional antiferromagnetic ma- terials with giant piezomagnetism and noncollinear spin current, Nat. Commun.12, 2846 (2021)

    work page 2021

  12. [12]

    Y. Liu, J. Yu and C. C. Liu, Twisted Magnetic Van der Waals Bilayers: An Ideal Platform for Altermagnetism, Phys. Rev. Lett.133, 206702 (2024)

    work page 2024

  13. [13]

    X. Chen, D. Wang, L. Y. Li and B. Sanyal, Giant spin- splitting and tunable spin-momentum locked transport in room temperature collinear antiferromagnetic semimetal- lic CrO monolayer, Appl. Phys. Lett.123, 022402 (2023)

    work page 2023

  14. [14]

    B. Pan, P. Zhou, P. Lyu, H. Xiao, X. Yang, and L. Sun, General stacking theory for altermagnetism in bi- layer systems, Phys. Rev. Lett.133, 166701 (2024)

    work page 2024

  15. [15]

    Zhang and G

    L. Zhang and G. Gao, Dimension- and Facet-Dependent Altermagnetic Biferroics and Ferromagnetic Biferroics and Triferroics in CrSb, Adv. Funct. Mater.36, e25978 (2026). 7

    work page 2026

  16. [16]

    H. Bai, L. Han, X. Y. Feng, Y. J. Zhou, R. X. Su, Q. Wang, L. Y. Liao, W. X. Zhu, X. Z. Chen, F. Pan, X. L. Fan, and C. Song, Observation of spin splitting torque in a collinear antiferromagnet RuO 2, Phys. Rev. Lett.128, 197202 (2022)

    work page 2022

  17. [17]

    S. Lee, S. Lee, S. Jung, J. Jung, D. Kim, Y. Lee, B. Seok, J. Kim, B. G. Park, L. Smejkal, C. J. Kang, and C. Kim, Broken Kramers degeneracy in altermagnetic MnTe, Phys. Rev. Lett.132, 036702 (2024)

    work page 2024

  18. [18]

    G. Yang, Z. Li, S. Yang, J. Li, H. Zheng, W. Zhu, Z. Pan, Y. Xu, S. Cao, W. Zhao, A. Jana, J. Zhang, M. Ye, Y. Song, L. H. Hu, L. Yang, J. Fujii, I. Vobornik, M. Shi, H. Yuan, Y. Zhang, Y. Xu, and Y. Liu, Three-dimensional mapping of the altermagnetic spin splitting in CrSb, Nat Commun16, 1442 (2025)

    work page 2025

  19. [19]

    Z. Zhou, X. Cheng, M. Hu, R. Chu, H. Bai, L. Han, J. Liu, F. Pan and C. Song, Manipulation of the altermag- netic order in CrSb via crystal symmetry, Nature638, 645 (2025)

    work page 2025

  20. [20]

    J. Ding, Z. Jiang, X. Chen, Z. Tao, Z. Liu, T. Li, J. Liu, J. Sun and J. Cheng, Large Band Splitting ing-Wave Altermagnet CrSb, Phys. Rev. Lett.133, 206401 (2024)

    work page 2024

  21. [21]

    Jiang, M

    B. Jiang, M. Hu, J. Bai, Z. Song, C. Mu, G. Qu, W. Li, W. Zhu, H. Pi, Z. Wei, Y. J. Sun, Y. Huang, X. Zheng, Y. Peng, L. He, S. Li, J. Luo, Z. Li, G. Chen, H. Li, H. Weng and T. Qian, A metallic room-temperature d-wave altermagnet, Nat. Phys.21, 754 (2025)

    work page 2025

  22. [22]

    F. Zhang X. Cheng, Z. Yin, C. Liu, L. Deng, Y. Qiao, Z. Shi, S. Zhang, J. Lin, Z. Liu, M. Ye, Y. Huang, X. Meng, C. Zhang, T. Okuda, K. Shimada, S. Cui, Y. Zhao, G.- H. Cao, S. Qiao, J. Liu and C. Chen, Crystal-symmetry- paired spin-valley locking in a layered room-temperature metallic altermagnet candidate, Nature Phys.21, 760 (2025)

    work page 2025

  23. [23]

    C.-C. Liu, J. Li, J.-Y. Liu, J.-Y. Lu, H.-X. Li, Y. Liu and G.-H. Cao, Physical properties and first-principles calculations of an altermagnet candidate Cs 1−δV2Te2O, Phys. Rev. B112, 224439 (2025)

    work page 2025

  24. [24]

    Y. Sun, Y. Huang, J. Cheng et al., Antiferromagnetic structure of KV 2Se2O: A neutron diffraction study, Phys. Rev. B112, 184416 (2025)

    work page 2025

  25. [25]

    S. D. Guo, Hidden altermagnetism, Front. Phys.21, 025201 (2026); arXiv:2411.13795 (2024)

    work page arXiv 2026

  26. [26]

    G. Yang, R. Chen, C. Liu et al., Observation of hid- den altermagnetism in Cs 1−δV2Te2O, arXiv:2512.00972 (2025)

    work page internal anchor Pith review Pith/arXiv arXiv 2025

  27. [27]

    W. Xie, C. Liu, F. Zhang et al., G-type antiferromagnetic structure in Rb 1−δV2Te2O, arXiv:2604.17365 (2026)

    work page internal anchor Pith review Pith/arXiv arXiv 2026

  28. [28]

    S. D. Guo, X. S. Guo, D. C. Liang and G. Wang, Symmetry-breaking induced transition among net-zero- magnetization magnets, J. Mater. Chem. C13, 11997 (2025)

    work page 2025

  29. [29]

    S. D. Guo, S. Chen and G. Wang, Spin ordering-induced fully-compensated ferrimagnetism achieved in bilayers of Cr2C2S6, Phys. Rev. B112, 134430 (2025)

    work page 2025

  30. [30]

    S. D. Guo, J. He and Y. S. Ang, Achieving fully- compensated ferrimagnetism through two-dimensional CrI3/CrGeTe3 heterojunctions, Appl. Phys. Lett.127, 232401 (2025)

    work page 2025

  31. [31]

    Y. Liu, X. Chen, Y. Yu et al., Symmetry classification of magnetic orders using oriented spin space groups, Nature 652, 869 (2026)

    work page 2026

  32. [32]

    Z. Han, Y. Song, Y. Jia, et al., Classification and Char- acterization Methods for Heterojunctions, Adv. Mater. Interfaces12, 2500191 (2025)

    work page 2025

  33. [33]

    Hohenberg and W

    P. Hohenberg and W. Kohn, Inhomogeneous Electron Gas, Phys. Rev.136, B864 (1964); W. Kohn and L. J. Sham, Self-Consistent Equations Including Exchange and Correlation Effects, Phys. Rev.140, A1133 (1965)

    work page 1964

  34. [34]

    Kresse, Ab initio molecular dynamics for liquid met- als, J

    G. Kresse, Ab initio molecular dynamics for liquid met- als, J. Non-Cryst. Solids193, 222 (1995)

    work page 1995

  35. [35]

    Kresse and J

    G. Kresse and J. Furthm¨uller, Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set, Comput. Mater. Sci. 6,15(1996)

    work page 1996

  36. [36]

    Kresse and D

    G. Kresse and D. Joubert, From ultrasoft pseudopoten- tials to the projector augmented-wave method, Phys. Rev. B59, 1758 (1999)

    work page 1999

  37. [37]

    J. P. Perdew, K. Burke and M. Ernzerhof, Generalized gradient approximation made simple, Phys. Rev. Lett. 77, 3865 (1996)

    work page 1996

  38. [38]

    P. Wang, D. X. Wu, K. Zhang and X. J. Wu, Two-Dimensional Quaternary Transition Metal Sulfide CrMoA2S6 (A = C, Si, or Ge): A Bipolar Antiferromag- netic Semiconductor with a High N´eel Temperature, J. Phys. Chem. Lett.13, 3850 (2022)

    work page 2022

  39. [39]

    S. L. Dudarev, G. A. Botton, S. Y. Savrasov, C. J. Humphreys, and A. P. Sutton, Electron-energy-loss spec- tra and the structural stability of nickel oxide: An LSDA+U study, Phys. Rev. B57, 1505 (1998)

    work page 1998

  40. [40]

    Grimme, S

    S. Grimme, S. Ehrlich and L. Goerigk, Effect of the damping function in dispersion corrected density func- tional theory, J. Comput. Chem.32, 1456 (2011)

    work page 2011

  41. [41]

    Zhang, Q

    X. Zhang, Q. Liu, J. W. Luo, A. J. Freeman and A. Zunger, Hidden spin polarization in inversion-symmetric bulk crystals, Nat. Phys.10, 387 (2014)

    work page 2014

  42. [42]

    Zhang, S

    K. Zhang, S. Zhao, Z. Hao, S. Kumar, E. F. Schwier, Y. Zhang, H. Sun, Y. Wang, Y. Hao, X. Ma, C. Liu, L. Wang, X. Wang, K. Miyamoto, T. Okuda, C. Liu, J. Mei, K. Shimada, C. Chen, and Q. Liu, Observation of Spin-Momentum-Layer Locking in a Centrosymmetric Crystal, Phys. Rev. Lett.127, 126402 (2021)

    work page 2021

  43. [43]

    W. Yao, E. Wang, H. Huang, K. Deng, M. Yan, K. Zhang, K. Miyamoto, T. Okuda, L. Li, Y. Wang, H. Gao, C. Liu, W. Duan, and S. Zhou, Direct observation of spin-layer locking by local Rashba effect in monolayer semiconduct- ing PtSe2 film, Nat. Commun.8, 14216 (2017)

    work page 2017

  44. [44]

    S. Guan, J. X. Xiong, Z. Wang, and J. W. Luo, Progress of hidden spin polarization in inversion-symmetric crys- tals, Sci. China-Phys. Mech. Astron.65, 237301 (2022)

    work page 2022

  45. [45]

    L. D. Yuan, X. Zhang, C. M. Acosta and A. Zunger, Uncovering spin-orbit coupling-independent hidden spin polarization of energy bands in antiferromagnets, Nat. Commun.14, 5301 (2023)

    work page 2023