Pith. sign in

REVIEW 3 major objections 5 minor 54 references

On the Symmetries of Anisotropic Spin Interaction Models

T0 review · 3 major / 5 minor · reviewed 2026-08-02 · deepseek-v4-flash

Pith's one-line read Anisotropic spin interactions do not merely break spin-space symmetries; they twist them through cohomology invariants, producing exact symmetry groups that cannot be embedded in the conventional product of global spin rotations and spatial

desk verdict The tSSG skeleton and Klein-bottle application are novel, but the flagship eC4 example fails the staggered-field check. read the letter →

arxiv 2605.14969 v2 pith:QK3HX2CV submitted 2026-05-14 cond-mat.str-el

classification cond-mat.str-el MSC 81R0582D40
keywords anisotropicspininteractionsspin-spacegroupscohomologyinvariantstwistedgroupextensionsKleinbottlequadrupolarexcitationsflavorwavetheory
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

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

The reading

The paper argues that anisotropic spin interactions such as Dzyaloshinskii-Moriya exchange and single-ion anisotropy can change the type of symmetry realized by a spin model, not just reduce its symmetry group. The load-bearing example is a square-lattice model where a spin-decorated fourfold rotation obeys (eC4)^4 = R_z(pi), a cohomology invariant that cannot be removed by redefining the operation, so the full symmetry group is a third, distinct extension that is not conjugate to any subgroup of O(3) times the space group. The paper then shows that such twisted symmetries are captured by a general theory of twisted spin-space groups, and applies it to a spin-1 model whose quadrupolar excitations live on a Brillouin Klein bottle, with topological edge states sewn by a Möbius relation. A sympathetic reader cares because this recasts the symmetry language for anisotropic magnets and predicts a new class of topological magnetic excitations on nonorientable Brillouin manifolds.

What carries the argument

The central object is the site-dependent centralizer sector Z_g(r): an element of the centralizer of the spin-only group S0 that varies from site to site, encoding the difference between a twisted symmetry and a conventional one. Each tSSG operation is decomposed as g = (Z_g(r) R_g || l_g), where l_g is the lattice operation and R_g is a global normalizer spin rotation; the centralizer sector Z_g(r) produces a two-cocycle omega_2(l_g1, l_g2) in H^2_phi(GL, Z(S0)), and the cohomology class distinguishes tSSGs from subgroups of O(3) x Isom(R^3). In the spin-1 model, the effective mirror fMx = (Z_Mx(r) R_x(pi) || Mx) with Z_Mx(r) = (R_z(pi))^{r_y} is the mechanism that converts a mirror operati

What would settle it

Compute the commutator [H, eC4] on a finite cluster of the square-lattice model (1) with periodic boundary conditions, evaluating every bond and the staggered-field term; if it does not vanish identically for all couplings, the claimed third symmetry group G3 is not realized by this model and the non-embeddable symmetry class would not follow. Alternatively, verify numerically that M1(-kx, ky+pi) = -sigma_z M1(kx, ky) sigma_z holds for all momenta in the spin-1 model, and that the edge-state condition nu(ky)=1 persists under all symmetry-preserving perturbations.

Watch

Extended reading notes

Core claim

The central claim is that a spin operation eC4 = (Z_C4(r) R_x(pi) || C4), with site-dependent spin rotations Z_C4(r), is an exact symmetry of the anisotropic Hamiltonian (1), satisfying eC4 SO(2)_z (eC4)^{-1} = (SO(2)_z)^{-1} and (eC4)^4 = R_z(pi). Because this fourth power is a cohomology invariant, the group G3 generated by SO(2)_z and eC4 is one of exactly three groups with G/SO(2)_z ~= C4, yet it is neither the direct product nor the semidirect product and cannot be conjugated into O(3) x Isom(R^3). The paper generalizes this to a theory of twisted spin-space groups (tSSGs) based on the unitary spin-only group S0, in which every operation decomposes into a lattice part, a global normaliz

Load-bearing premise

The load-bearing premise is that the site-dependent spin rotations defining eC4 and eT are exact symmetries of the full infinite-lattice Hamiltonian (1) on every bond, site, and the staggered field, while the paper only specifies the pattern on a single square and leaves the exhaustive closure check to the reader.

Editorial extensions

If this is right

  • If the claim is correct, anisotropic spin Hamiltonians can possess exact symmetries outside O(3) x Isom(R^3), so the symmetry classification of magnetic materials with spin-orbit coupling must be enlarged to include twisted spin-space groups.
  • The spin-1 model's quadrupolar excitations are defined on a spin Brillouin Klein bottle rather than a torus, implying a Z2 topological classification and edge states with a nonlocal momentum twist omega_L(ky) = omega_R(ky+pi).
  • The cocycle-free construction shows that tSSGs with any chiral spin-only group S0 arise generically from the coexistence of on-site single-ion anisotropy and bond spin interactions, extending the mechanism beyond the specific example.
  • The theory provides a systematic language, with all spin point groups classified for the 11 chiral point groups, so future works on anisotropic magnets can use tSSGs as the symmetry framing.
  • The site-dependent centralizer sector can be interpreted as a spin gauge, suggesting that tSSGs are a magnetically realized form of projective crystalline symmetry.

Reading between the lines

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

  • If the closure of site-dependent rotations is verified on the infinite lattice, existing spin-space-group classifications of altermagnets and topological magnon systems would need to be revisited whenever anisotropic exchange or single-ion terms are present, because those systems could realize twisted rather than conventional symmetry groups.
  • The Klein-bottle spin Brillouin zone suggests a concrete experimental or simulator search: engineer a large-D spin-1 system on a pm wallpaper with the bond patterns of model (13) and look for glide-symmetric spectral intensity in inelastic neutron scattering or momentum-resolved spectroscopy as a fingerprint of the twisted symmetry.
  • A direct extension would compute the dynamical structure factor of model (13) and check whether the glide sewing relation leaves a characteristic spectral signature, which would serve as a falsifiable prediction of the tSSG framework.
  • The cohomology invariant (eC4)^4 = R_z(pi) could manifest as a projective phase in weakly entangled or response measurements, potentially offering a bulk observable that distinguishes G3 from conventional spin point groups.
Share X Bluesky LinkedIn Reddit HN

Signed reviews

No signed human review yet.

Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

3 major / 5 minor

Summary. The paper develops a group-theoretic framework, termed twisted spin-space groups (tSSGs), for anisotropic spin Hamiltonians. The key idea is to take the spin-only group S0 to consist of proper on-site spin rotations that are exact symmetries, and to decompose any symmetry operation into a lattice part, a global normalizer spin rotation, and a site-dependent centralizer sector. The site-dependent sector is argued to encode a two-cocycle in H^2_phi(G_L, Z(S0)), producing groups that cannot be embedded in O(3) x Isom(R^3). The paper claims model (1) realizes a non-embeddable extension G3 with quotient C4 and invariant (eC4)^4 = R_z(pi), and then analyzes a spin-1 model (13) whose {Q_xz, Q_yz} sector is claimed to live on a momentum-space Klein bottle, with glide sewing relation and a Möbius edge-sewing relation. The Supplemental Material provides a reformulation of conventional SSGs, a derivation of the twisted multiplication law, a cocycle-free construction of tSSGs, exact ribbon solutions for the spin-1 model, and an extensive enumeration of spin point groups.

Significance. If correct, the framework would establish that exact symmetries of anisotropic spin models need not be subgroups of O(3) x Isom(R^3), and it would provide a concrete construction of topological quadrupolar bands on nonorientable spin Brillouin zones. The paper has several genuine strengths: the classification of C4 extensions by H^2 is mathematically sound; the spin-1 model is treated analytically rather than numerically, with explicit sewing relations and a winding invariant; and the SM contains a large systematic enumeration with clear algorithmic workflow. The work is not circular or data-fitting: the topological invariants are computed from the stated Hamiltonians, and the models have free real parameters. However, the flagship example based on model (1) has a load-bearing flaw that must be addressed before the paper can be accepted.

major comments (3)
  1. [§2, Eq. (1) and Eq. (3)] The claimed eC4 symmetry is inconsistent with the staggered field H_a for h≠0. The spin part of eC4 = (Z_C4(r) R_x(π) || C4) maps S^z_r to −S^z_r, because Z_C4(r) ∈ SO(2)_z commutes with S^z and R_x(π) reverses it; the spatial C4 preserves (r_x+r_y) mod 2. Hence H_a transforms to −H_a, so Eq. (1) is not invariant under eC4. Consequently the primary demonstration of the non-embeddable group G3 with (eC4)^4 = R_z(π) is not established. If the intended model has h=0, this must be stated and the full lattice consistency checked; as written this is a load-bearing error.
  2. [§2, Fig. 1 and text around Eq. (2)] Z_C4(r) is specified only 'on a single square,' with no formula for its extension to the infinite lattice Z^2. A symmetry of the infinite-lattice Hamiltonian requires a global site-dependent assignment that is consistent with translations, with all x- and y-bonds, and with eT. The paper asserts this without verification. Given that eC4 is the central example of a twisted group, please provide the explicit assignment and a complete check of Eq. (1).
  3. [Abstract and §1] The sentence that anisotropic spin interactions 'do not merely break ... but instead twist them' is supported only by the two engineered models (1) and (13), not by a proof that anisotropy generically produces twisted groups. If the eC4 example is repaired or removed, please temper the generalization to a claim that anisotropic interactions can realize tSSG symmetries, or supply a general argument that the cocycle-free construction of §S3 applies to generic couplings.
minor comments (5)
  1. [§2] Typo: 'Speficifically' should be 'Specifically'.
  2. [§4 and SM S4] Typos: 'lineara=0,b=λ' and 'exactly solvable linea=0,b=λ' should read 'line a=0, b=λ'.
  3. [SM S3] The reference to Serre is unresolved in the SM: 'Serre's book [?]' should be a numbered citation.
  4. [§2, Eqs. (3)-(4)] Notation is overloaded: C4 in Eq. (4) denotes the operation {R_x(π)||C4}, while eC4 includes a site-dependent Z sector. Please use distinct symbols and define the sign conventions for R_x(π) versus −R_x(π) clearly.
  5. [Fig. 1 caption] The caption says 'each θ∈[0,2π)' stands for a local spin rotation, but only the four discrete values ±π/4 and ±3π/4 are used. Please clarify.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity; construction and computations are self-contained.

full rationale

The paper's derivation chain is self-contained rather than circular. The central objects, eC4 in Eq. (3) and fMx in model (13), are explicitly constructed site-dependent spin operations, and the claimed relations are computed from those stated definitions rather than imported as conclusions. The group-extension classification of the three groups with G/SO(2)_z ≅ C4 is argued directly in the text and footnote using standard cohomology, and the tSSG multiplication law is derived in the Supplemental Material (S2). The spin-1 model's predictions — the glide-reflection sewing relation, the Möbius edge relation ω_L(k_y)=ω_R(k_y+π), and the winding ν(k_y) — are analytic results obtained from the explicit Hamiltonian (13) with free real parameters, not fitted quantities. Self-citations such as Ref. [27] appear only as background references in a list of conventional SSG classifications and are not load-bearing for the paper's new claims. Even if the asserted eC4 symmetry of Eq. (1) is questionable due to the staggered field, that would be a correctness issue, not a circularity issue: the paper does not define eC4 in terms of the conclusion it purports to derive. No prediction reduces by construction to its own input.

Assumptions & free parameters 3 free parameters · 6 assumptions · 3 invented entities

The paper introduces no fitted parameters: the Hamiltonian couplings are free inputs and the claims are parameter-independent (topology depends only on the regime ratio |gamma sin k_y| < |lambda|). The axioms are mostly standard domain assumptions; the two definitional choices (S0 proper-rotation-only; O(3)-realized conjugations) are stated but not derived. The invented entities are realizable theoretical structures with concrete spectral handles rather than ad hoc physical objects.

free parameters (3)
  • Solvable-line specialization for the ribbon problem = a = 0, b = lambda
    Chosen in SM S4.D to make the edge recursion triangular and exactly solvable. The glide sewing and winding hold for generic parameters, but the closed-form edge-mode theorem (Theorem 1) is proven only on this line.
  • Single-ion anisotropy D (large-D limit) = D >> 1 (with stability bounds unstated)
    The ferroquadrupolar vacuum and harmonic expansion require D large; the positivity conditions on the bosonic spectrum (e.g., D + 4a cos k_x +/- 4 rho(k) > 0, D +/- 4 beta cos k_y > 0) are never stated.
  • Topological window ratio gamma/lambda = |gamma sin k_y| < |lambda| (example: lambda = 1, gamma = 0.9)
    Regime condition determining where the winding nu = 1 and edge modes exist; an input condition, not fitted to data.
assumptions (6)
  • domain assumption XY-DM gauge equivalence (Shekhtman-Entin-Wohlman-Aharony, refs 47-48): a DM bond is locally gauge-equivalent to an XY bond up to site-dependent z-rotations
    Used to justify that eC4 with site-dependent Z_C4(r) maps the x-bond XY term to the y-bond DM term (main text, 'A minimal model' section, Eqs. 2-3).
  • domain assumption Spin-only group S0 is the group of on-site global proper rotations (S0 subset of SO(3)); the antiunitary effective time-reversal is removed from S0
    Definitional foundation of the whole formalism (Basic Setup); motivated by the model but not derived.
  • ad hoc to paper The conjugation action of any operation in G on S0 must be realized by elements of O(3)
    Explicitly imposed restriction (Basic Setup paragraph) to exclude an 'SU(3) theory'; reasonable for standard spin rotations but stated as a restriction, not derived.
  • domain assumption Harmonic (linear flavor wave) expansion about the large-D ferroquadrupolar vacuum captures the topological content
    The Klein-bottle bands, edge modes, and Z2 claims are established at harmonic order; higher-order stability and anharmonic effects are not analyzed (SM S4.A).
  • standard math Standard group-extension and cohomology machinery (Schreier theory; H^2_phi(G_L, Z(S0)) classifies extensions)
    Used throughout (footnote 49; SM S3). I verified the key computation H^2_phi(C4, SO(2)) = Z2.
  • domain assumption The free action of the glide (k_x, k_y) -> (-k_x, k_y + pi) makes the fundamental domain a Klein bottle, with band classification from refs 44-46, 51-52
    Topological identification used in the 'Topological quadrupolar bands' section.
invented entities (3)
  • Twisted spin-space group (tSSG) - symmetry group G/S0 ~= G_L with nontrivial centralizer sector and cocycle [omega2] in H^2_phi(G_L, Z(S0)) independent evidence
    purpose: Formal object capturing exact symmetries of anisotropic spin models that do not embed in O(3)xIsom(R^3)
    Realized explicitly by Hamiltonians (1) and (13); makes falsifiable predictions (glide sewing Eq. 16, Möbius edge sewing omega_L(k_y) = omega_R(k_y+pi), winding-controlled edge modes) checkable by spectroscopy or simulator experiments.
  • Spin Brillouin Klein-bottle - nonorientable momentum-space fundamental domain for the {Q_xz, Q_yz} sector independent evidence
    purpose: Describes band topology of quadrupolar excitations
    The momentum-space glide (Eq. 15) and the edge-mode sewing (Theorem 1) are concrete, observable signatures; the concept is borrowed from electronic systems (refs 44-46) but its realization in magnetic quadrupolar excitations is new.
  • Site-dependent centralizer sector Z_g(r) as part of a symmetry operation independent evidence
    purpose: Encodes cohomology twists and enables non-embeddable symmetry groups
    Explicitly constructed for C4, T, and Mx in the two models; the (C4)^4 = R_z(pi) relation and the momentum shift k_y -> k_y + pi are its testable consequences.

how reviews work

0 comments
Cite this review

Pith. "Pith review of On the Symmetries of Anisotropic Spin Interaction Models." pith.science (2026). https://pith.science/paper/QK3HX2CV

@misc{pith2026260514969,
  author       = {Pith},
  title        = {Pith review of: On the Symmetries of Anisotropic Spin Interaction Models},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/QK3HX2CV}},
  note         = {Machine review of arXiv:2605.14969}
}
abstract

We show that anisotropic spin interactions do not merely break spin-space group (SSG) symmetries, but instead twist them through cohomology invariants, yielding symmetry classes beyond subgroups of $ O(3)\times \operatorname{Isom}(\mathbb{R}^3) $. This requires redefining the spin-only group $ S_0 $ in terms of proper spin rotations. Based on this unitary $ S_0 $, we formulate a twisted SSG (tSSG) theory that captures the complete set of spin-space symmetries. We then study a spin-1 model with tSSG symmetry using linear flavor wave theory and find $\mathbb{Z}_2$ topological quadrupolar excitations defined on a spin Brillouin Klein bottle. Specifically, the quadrupolar excitations possess a momentum-space glide-reflection symmetry and the edge states exhibit a nonlocal momentum twist. These results establish the symmetry language required for interacting spin systems, whether realized in magnetic materials or on programmable quantum simulators, and open a route to unconventional magnetism.

Figures

Figures reproduced from arXiv: 2605.14969 by the authors.

Figure 1
Figure 1. FIG. 1. Spin model with twisted collinear SSG symmetries [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. In this setting, the group homomorphism Rˆ is fixed by the symmetries of Hsite, while Hbond admits site￾dependent sector valued in ZSO(3)(S0) ⊆ ZSO(3) Z(S0)  . FIG. 2. The Hamiltonian (12) realizing tSSGs with arbitrary S0. The upper layer represents the spin-exchange Hamilto￾nian Hbond, while the lower layer represents the on-site single￾ion anisotropy Hamiltonian Hsite. A Hamiltonian with such tSSG symmetry there… view at source ↗

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

54 extracted references · 6 linked inside Pith

  1. [1]

    Serre , in booktitle Finite Groups: An Introduction ( publisher International Press of Boston , address Somerville, MA , year 2016 ), vol

    author J.-P. Serre , in booktitle Finite Groups: An Introduction ( publisher International Press of Boston , address Somerville, MA , year 2016 ), vol. volume 10 of series Surveys of Modern Mathematics , pp. pages 51--69 , ISBN isbn 978-1-57146-320-3

  2. [2]

    Liu , author J

    author P. Liu , author J. Li , author J. Han , author X. Wan , and author Q. Liu , journal Phys. Rev. X volume 12 , pages 021016 ( year 2022 )

  3. [3]

    Yang , author Z.-X

    author J. Yang , author Z.-X. Liu , and author C. Fang , journal Nat. Commun. volume 15 , pages 10203 ( year 2024 )

  4. [4]

    Guo , author Y.-W

    author P.-J. Guo , author Y.-W. Wei , author K. Liu , author Z.-X. Liu , and author Z.-Y. Lu , journal Phys. Rev. Lett. volume 127 , pages 176401 ( year 2021 )

  5. [5]

    author S. A. A. Ghorashi , author T. L. Hughes , and author J. Cano , journal Phys. Rev. Lett. volume 133 , pages 106601 ( year 2024 ), 2306.09413

  6. [6]

    Katsura , author N

    author H. Katsura , author N. Nagaosa , and author P. A. Lee , journal Phys. Rev. Lett. volume 104 , pages 066403 ( year 2010 )

  7. [7]

    author A. V. Chumak , author V. I. Vasyuchka , author A. A. Serga , and author B. Hillebrands , journal Nat. Phys. volume 11 , pages 453 ( year 2015 )

  8. [8]

    Chisnell , author J

    author R. Chisnell , author J. S. Helton , author D. E. Freedman , author D. K. Singh , author R. I. Bewley , author D. G. Nocera , and author Y. S. Lee , journal Phys. Rev. Lett. volume 115 , pages 147201 ( year 2015 )

Show all 54 references
  1. [9]

    Cheng , author S

    author R. Cheng , author S. Okamoto , and author D. Xiao , journal Phys. Rev. Lett. volume 117 , pages 217202 ( year 2016 )

  2. [10]

    Li , author C

    author K. Li , author C. Li , author J. Hu , author Y. Li , and author C. Fang , journal Phys. Rev. Lett. volume 119 , pages 247202 ( year 2017 )

  3. [11]

    Yao , author C

    author W. Yao , author C. Li , author L. Wang , author S. Xue , author Y. Dan , author K. Iida , author K. Kamazawa , author K. Li , author C. Fang , and author Y. Li , journal Nat. Phys. volume 14 , pages 1011 ( year 2018 )

  4. [12]

    Corticelli , author R

    author A. Corticelli , author R. Moessner , and author P. A. McClarty , journal Phys. Rev. B volume 105 , pages 064430 ( year 2022 )

  5. [13]

    Corticelli , author R

    author A. Corticelli , author R. Moessner , and author P. A. McClarty , journal Phys. Rev. Lett. volume 130 , pages 206702 ( year 2023 )

  6. [14]

    Chen , author Y

    author X. Chen , author Y. Liu , author P. Liu , author Y. Yu , author J. Ren , author J. Li , author A. Zhang , and author Q. Liu , journal Nature volume 640 , pages 349 ( year 2025 )

  7. [15]

    S mejkal , author J

    author L. S mejkal , author J. Sinova , and author T. Jungwirth , journal Phys. Rev. X volume 12 , pages 040501 ( year 2022 a ), 2204.10844

  8. [16]

    Cheong and author X

    author S.-W. Cheong and author X. Xu , journal npj Quantum Mater. volume 7 , pages 40 ( year 2022 )

  9. [17]

    Bose , author N

    author A. Bose , author N. J. Schreiber , author R. Jain , author D.-F. Shao , author H. P. Nair , author J. Sun , author X. S. Zhang , author D. A. Muller , author E. Y. Tsymbal , author D. G. Schlom , et al. , journal Nat. Electron. volume 5 , pages 267 ( year 2022 ), 2108.09150

  10. [18]

    Feng , author X

    author Z. Feng , author X. Zhou , author L. S mejkal , author L. Wu , author Z. Zhu , author H. Guo , author R. Gonz \'a lez-Hern \'a ndez , author X. Wang , author H. Yan , author P. Qin , et al. , journal Nat. Electron. volume 5 , pages 735 ( year 2022 )

  11. [19]

    Karube , author T

    author S. Karube , author T. Tanaka , author D. Sugawara , author N. Kadoguchi , author M. Kohda , and author J. Nitta , journal Phys. Rev. Lett. volume 129 , pages 137201 ( year 2022 ), 2111.07487

  12. [20]

    Bai , author L

    author H. Bai , author L. Han , author X. Y. Feng , author Y. J. Zhou , author R. X. Su , author Q. Wang , author L. Y. Liao , author W. X. Zhu , author X. Z. Chen , author F. Pan , et al. , journal Phys. Rev. Lett. volume 128 , pages 197202 ( year 2022 ), 2109.05933

  13. [21]

    S mejkal , author J

    author L. S mejkal , author J. Sinova , and author T. Jungwirth , journal Phys. Rev. X volume 12 , pages 031042 ( year 2022 b )

  14. [22]

    Mazin , journal Phys

    author I. Mazin , journal Phys. Rev. X volume 12 , pages 040002 ( year 2022 ), 2212.13110

  15. [23]

    author W. F. Brinkman and author R. J. Elliott , journal Proc. R. Soc. London, Ser. A volume 294 , pages 343 ( year 1966 )

  16. [24]

    author D. B. Litvin and author W. Opechowski , journal Physica volume 76 , pages 538 ( year 1974 )

  17. [25]

    Jiang , author Z

    author Y. Jiang , author Z. Song , author T. Zhu , author Z. Fang , author H. Weng , author Z.-X. Liu , author J. Yang , and author C. Fang , journal Phys. Rev. X volume 14 , pages 031039 ( year 2024 )

  18. [26]

    Chen , author J

    author X. Chen , author J. Ren , author Y. Zhu , author Y. Yu , author A. Zhang , author P. Liu , author J. Li , author Y. Liu , author C. Li , and author Q. Liu , journal Phys. Rev. X volume 14 , pages 031038 ( year 2024 )

  19. [27]

    Xiao , author J

    author Z. Xiao , author J. Zhao , author Y. Li , author R. Shindou , and author Z.-D. Song , journal Phys. Rev. X volume 14 , pages 031037 ( year 2024 )

  20. [28]

    Song , author A

    author Z. Song , author A. Z. Yang , author Y. Jiang , author Z. Fang , author J. Yang , author C. Fang , author H. Weng , and author Z.-X. Liu , journal Phys. Rev. B volume 111 , pages 134407 ( year 2025 )

  21. [29]

    author S. V. Halilov , author A. Y. Perlov , author P. M. Oppeneer , author A. N. Yaresko , and author V. N. Antonov , journal Phys. Rev. B volume 57 , pages 9557 ( year 1998 )

  22. [30]

    Nagaosa and author Y

    author N. Nagaosa and author Y. Tokura , journal Nat. Nanotechnol. volume 8 , pages 899 ( year 2013 )

  23. [31]

    Fert , author V

    author A. Fert , author V. Cros , and author J. Sampaio , journal Nat. Nanotechnol. volume 8 , pages 152 ( year 2013 )

  24. [32]

    author H. T. Nembach , author J. M. Shaw , author M. Weiler , author E. Ju \'e , and author T. J. Silva , journal Nat. Phys. volume 11 , pages 825 ( year 2015 )

  25. [33]

    author S. M. Winter , author A. A. Tsirlin , author M. Daghofer , author J. van den Brink , author Y. Singh , author H. O. Jeschke , and author R. Valent \'i , journal J. Phys.: Condens. Matter volume 29 , pages 493002 ( year 2017 )

  26. [34]

    Takagi , author T

    author H. Takagi , author T. Takayama , author G. Jackeli , author G. Khaliullin , and author S. E. Nagler , journal Nat. Rev. Phys. volume 1 , pages 264 ( year 2019 )

  27. [35]

    Dzyaloshinsky , journal J

    author A. Dzyaloshinsky , journal J. Phys. Chem. Solids volume 4 , pages 241 ( year 1958 )

  28. [36]

    Moriya , journal Phys

    author T. Moriya , journal Phys. Rev. volume 120 , pages 91 ( year 1960 )

  29. [37]

    Dorier , author F

    author J. Dorier , author F. Becca , and author F. Mila , journal Phys. Rev. B volume 72 , pages 024448 ( year 2005 )

  30. [38]

    Kitaev , journal Ann

    author A. Kitaev , journal Ann. Phys. (N.Y.) volume 321 , pages 2 ( year 2006 )

  31. [39]

    Jackeli and author G

    author G. Jackeli and author G. Khaliullin , journal Phys. Rev. Lett. volume 102 , pages 017205 ( year 2009 )

  32. [40]

    Nussinov and author J

    author Z. Nussinov and author J. van den Brink , journal Rev. Mod. Phys. volume 87 , pages 1 ( year 2015 )

  33. [41]

    Sachidanandam , author T

    author R. Sachidanandam , author T. Yildirim , author A. B. Harris , author A. Aharony , and author O. Entin-Wohlman , journal Phys. Rev. B volume 56 , pages 260 ( year 1997 )

  34. [42]

    author G. A. Craig and author M. Murrie , journal Chem. Soc. Rev. volume 44 , pages 2135 ( year 2015 )

  35. [43]

    Meng , author S.-D

    author Y.-S. Meng , author S.-D. Jiang , author B.-W. Wang , and author S. Gao , journal Acc. Chem. Res. volume 49 , pages 2381 ( year 2016 )

  36. [44]

    Schiff , author A

    author H. Schiff , author A. Corticelli , author A. Guerreiro , author J. Romh \'a nyi , and author P. A. McClarty , journal SciPost Phys. volume 18 , pages 109 ( year 2025 )

  37. [45]

    Chen , author S

    author Z. Chen , author S. A. Yang , and author Y. Zhao , journal Nat. Commun. volume 13 , pages 2215 ( year 2022 )

  38. [46]

    Zhang , author S

    author C. Zhang , author S. A. Yang , and author Y. Zhao , journal Mater. Today Quantum p. pages 100055 ( year 2025 a )

  39. [47]

    Zhang , author P

    author C. Zhang , author P. Wang , author J. Lyu , and author Y. Zhao , journal Phys. Rev. Lett. volume 135 , pages 136601 ( year 2025 b )

  40. [48]

    Shekhtman , author O

    author L. Shekhtman , author O. Entin-Wohlman , and author A. Aharony , journal Phys. Rev. Lett. volume 69 , pages 836 ( year 1992 )

  41. [49]

    Yildirim , author A

    author T. Yildirim , author A. B. Harris , author A. Aharony , and author O. Entin-Wohlman , journal Phys. Rev. B volume 52 , pages 10239 ( year 1995 )

  42. [50]

    For _0 , the unique solution is the direct product SO(2) Z _4

    note From the perspective of group extensions, Z _4=\ 1,z,z^2,z^3\ admits two distinct actions on SO(2) , corresponding to the trivial homomorphism _0: Z _4 Aut (SO(2)) Z _2 and the nontrivial one _1: Z _4 Aut (SO(2)) . For _0 , the unique solution is the direct product SO(2) ...

  43. [51]

    Segal , journal Publications Math \'e matiques de l'IH \'E S volume 34 , pages 129 ( year 1968 )

    author G. Segal , journal Publications Math \'e matiques de l'IH \'E S volume 34 , pages 129 ( year 1968 )

  44. [52]

    note Mathematically, an equivariant bundle with structure group \( G \) acting freely on a base space \( X \) is equivalent to a bundle over the orbit space \( X/G \)

  45. [53]

    Katsura , author N

    author H. Katsura , author N. Nagaosa , and author A. V. Balatsky , journal Phys. Rev. Lett. volume 95 , pages 057205 ( year 2005 )

  46. [54]

    Zhang , author Z

    author C. Zhang , author Z. Chen , author Z. Zhang , and author Y. Zhao , journal Phys. Rev. Lett. volume 130 , pages 256601 ( year 2023 )

Pith tools

Reviewed August 2, 2026 · model on record in the stance chip above.