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Raman spectroscopic signature of Kitaev magnetism and complex spin-lattice coupling in S = 1/2 antiferromagnet SrLaCoNbO$_6$ double perovskite

T0 review · 1 major / 8 minor · reviewed 2026-07-09 · glm-5.2

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Pith's one-line read Raman signatures suggest Kitaev magnetism in 3d cobaltate

desk verdict First Raman+EXAFS study of a 3d Co2+ double perovskite seeking Kitaev-like signatures; data is solid but the Kitaev interpretation rests on elimination arguments, not direct magnetic evidence. read the letter →

arxiv 2607.07630 v1 pith:5GKP7K3L submitted 2026-07-08 cond-mat.str-el

Ajay Kumar , Clemens Ulrich , Rajendra S. Dhaka This is my paper · ORCID
classification cond-mat.str-el PACS 75.10.Kt75.30.Et63.20.kg78.30.-j
keywords KitaevmagnetismRamanspectroscopyspin-phononcouplingdoubleperovskitecobaltateFanolineshapeEXAFSquantumspinliquid
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

This paper argues that the double perovskite SrLaCoNbO6, a Co2+ (3d7) insulating antiferromagnet with weak spin-orbit coupling, shows spectroscopic evidence for fluctuating bond-directional (Kitaev-type) magnetic correlations persisting well above its ordering temperature of 15 K. The authors combine temperature-dependent Raman spectroscopy with Co K-edge EXAFS to document phonon self-energy anomalies at 60 K and 160-180 K, Fano line shapes in low-energy phonon modes S4-S6, an excitation-energy-independent broad continuum, and quasielastic scattering, alongside local structural distortions around Co. By ruling out luminescence (via excitation-energy independence) and electronic Raman scattering (via the insulating gap), they attribute the Fano coupling and continuum to magnetic fluctuations. The theoretical basis is the prediction that Co2+ in a weak crystal field retains an unquenched orbital moment, yielding a pseudospin-1/2 Kramers doublet ground state that can support bond-directional exchange. If the interpretation is correct, Kitaev physics would not require strong 5d spin-orbit coupling and could be sought in a broader class of 3d transition-metal oxides.

What carries the argument

The mechanism carrying the argument is the coupling between discrete optical phonons and a low-energy fluctuation spectrum of presumed magnetic origin, detected through Fano line shapes, phonon self-energy renormalization, and a broad Raman continuum. The theoretical underpinning is the pseudospin-1/2 Kramers doublet ground state of Co2+ (3d7, 4T1) in a weak crystal field, which retains unquenched orbital angular momentum and can mediate bond-directional exchange interactions, as predicted by Liu and Khaliullin (Ref. 34).

What would settle it

Inelastic neutron scattering or muon spin relaxation measurements that fail to detect short-range magnetic correlations or a magnetic continuum above 15 K in SrLaCoNbO6 would directly falsify the Kitaev interpretation. Alternatively, temperature-dependent EXAFS at the nonmagnetic Nb edge showing the same local structural changes at 60 K and 160 K would shift the explanation from magnetic fluctuations to structural distortions.

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Extended reading notes

Core claim

The central discovery is a set of correlated Raman and EXAFS anomalies in SrLaCoNbO6, appearing at 60 K and 160-180 K, that the authors interpret as fingerprints of spin-lattice coupling driven by fluctuating Kitaev-like magnetic correlations in the paramagnetic regime of a 3d Co2+ system. The key diagnostic signatures are Fano-asymmetric low-energy phonon modes (indicating phonon coupling to a continuum), a broad low-energy Raman continuum that is independent of laser excitation energy (ruling out luminescence), and quasielastic scattering, all of which persist above the antiferromagnetic ordering temperature TN=15 K.

Load-bearing premise

The load-bearing premise is that the observed Fano line shapes, broad continuum, and phonon anomalies originate from coupling to magnetic fluctuations rather than from purely structural effects such as local octahedral distortions or A-site disorder, given that no direct magnetic probe confirms the magnetic origin and no thermodynamic anomaly appears at 60 K.

Editorial extensions

If this is right

  • If Kitaev-like correlations exist in 3d Co2+ systems, the search for proximate quantum spin liquid behavior extends well beyond expensive 5d iridates and ruthenates to more chemically accessible cobalt oxides.
  • Raman spectroscopy combined with EXAFS could serve as a screening protocol for bond-directional exchange in candidate materials where direct magnetic probes like inelastic neutron scattering are not immediately available.
  • The 60 K anomaly, occurring without a corresponding signal in magnetization or specific heat, would imply that short-range magnetic correlations can produce measurable lattice distortions through magnetostriction without leaving a thermodynamic signature.
  • Double perovskites with frustrated fcc sublattices and competing 90-degree superexchange pathways may form a broader family where Kitaev interactions arise from geometry and orbital physics rather than from strong spin-orbit coupling alone.

Reading between the lines

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

  • The attribution of the Raman continuum to magnetic fluctuations rests on elimination of alternative sources (luminescence, electronic scattering) rather than a positive magnetic measurement; inelastic neutron scattering or muSR on SrLaCoNbO6 would be the decisive test and could either confirm or falsify the Kitaev interpretation.
  • If the 60 K anomaly is instead driven by A-site disorder or octahedral tilting rather than magnetic correlations, the Fano line shapes and continuum could still reflect coupling to lattice disorder rather than fractionalized magnetic excitations, weakening the Kitaev claim.
  • The comparison to 5d iridate double perovskites (A2ZnIrO6) that show similar Raman signatures is suggestive, but the spin-orbit coupling in Co2+ is an order of magnitude weaker; the persistence of Kitaev interactions would depend sensitively on how well the 4T1 orbital degeneracy is preserved against Jahn-Teller distortions and crystal-field splitting.
  • Temperature-dependent EXAFS at the nonmagnetic Nb edge, as the authors themselves suggest, could disentangle magnetic from structural contributions to the observed lattice distortions and would be a natural next experiment.
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Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

1 major / 8 minor

Summary. This manuscript reports temperature-dependent Raman spectroscopy (12–300 K) and Co K-edge EXAFS (21–300 K) measurements on the double perovskite SrLaCoNbO$_6$, a Co$^{2+}$ ($3d^7$) system with a Kramers-doublet ground state ($S̃=1/2$) on an fcc sublattice. The authors observe anomalies in phonon frequencies, linewidths, and intensities near 60 K (well above $T_N ≈ 15$ K) and 160–180 K, Fano line shapes in low-energy modes S4–S6, a broad excitation-energy-independent continuum, and quasielastic scattering. EXAFS reveals correlated changes in bond distances and Debye–Waller factors near the same temperatures. The authors interpret these signatures as evidence for spin–lattice coupling and fluctuating magnetic correlations consistent with proximate Kitaev-like physics, as theoretically proposed for $d^7$ cobalt systems by Liu and Khaliullin (Ref. 34). The data collection and fitting procedures (Voigt/Fano profiles, anharmonic decay model, standard EXAFS analysis) are competently executed. However, the central interpretive claim—linking the observed Raman anomalies to Kitaev-type magnetic fluctuations—rests on a chain of elimination that does not adequately rule out alternative explanations, most notably crystal-field excitations of the Co$^{2+}$ $^4T_1$ multiplet.

Significance. The experimental work is carefully carried out, with standard and appropriate methodology for both Raman and EXAFS. The observation of Fano line shapes, excitation-energy-independent continuum, and correlated EXAFS anomalies in a 3d cobaltate is a genuine contribution to the study of spin–lattice coupling in frustrated magnets. The attempt to connect these observations to the Liu–Khaliullin theoretical framework for Kitaev interactions in d7 systems is well motivated. However, the significance is substantially reduced by the absence of any quantitative comparison to the predicted Kitaev Raman response (unlike in 5d iridate analogues) and by the failure to rule out crystal-field excitations as the source of the Fano continuum. The paper does not present falsifiable predictions or machine-checked results; the EXAFS fitting is standard but not reproducible from the manuscript alone (data not publicly available).

major comments (1)
  1. §IV, elimination chain, step (3): The Fano continuum is attributed to magnetic fluctuations by ruling out luminescence (excitation-energy independence) and electronic continuum (insulating nature). However, crystal-field excitations of the Co²⁺ (d⁷) ⁴T₁ multiplet—split by spin-orbit coupling into a Kramers doublet ground state plus excited quartet and sextet states (§I)—are a well-known source of Fano line shapes and broad continua in insulating transition-metal oxides (the authors themselves cite LaTiO₃, Ref. 26, in this context). Phonon coupling to these crystal-field levels is not discussed or ruled out. This is a load-bearing gap: if the continuum originates from crystal-field excitations rather than magnetic fluctuations, the central claim of 'proximate Kitaev-like correlations' does not follow. The authors should either estimate the expected crystal-field excitation energies and R曼
minor comments (8)
  1. Title: 'Raman spectroscopic signature of Kitaev magnetism' overstates the strength of the evidence presented. Consider softening to reflect the suggestive, not definitive, nature of the findings.
  2. Abstract: 'consistent with fluctuating bond-directional interactions and proximate Kitaev-like correlations' could be qualified with 'potentially' or 'suggestive of' to better reflect the elimination-based argument.
  3. §III.A: The statement that mode P3 exhibits 'substantially larger linewidth than P2 and P4 across the entire temperature range' is attributed to 'lattice disorder,' but no quantitative measure of disorder (e.g., antisite disorder percentage, strain) is correlated with the linewidth. A brief comment on the expected disorder level from Refs. 35, 37 would strengthen this point.
  4. Fig. 2, insets: The deviation Δω is plotted on scales that differ by orders of magnitude between panels (e.g., panel (a) shows ~1.4 cm⁻¹ range, panel (c) shows ~0.9 cm⁻¹). A consistent scale or explicit note would aid comparison.
  5. Fig. 7: Several panels (d–m) show temperature-dependent parameters with only 'guides to the eye' (red lines). For the EXAFS Debye–Waller factors, a Debye model or correlated Debye model fit would provide a baseline against which anomalies could be more clearly identified.
  6. §IV: The comparison to A₂ZnIrO₆ (Refs. 6, 7, 19) would benefit from explicitly noting the key difference: in those 5d systems, the Raman continuum was compared quantitatively to the predicted Kitaev Raman response, whereas no such comparison is attempted here.
  7. References: Several arXiv-style formatting issues exist (e.g., 'R.. Moessner' in Ref. 2, 'N. B Perkins' missing period in Ref. 11). A proofreading pass is recommended.
  8. Data availability statement: 'available from the authors upon reasonable request' is acceptable but could be strengthened by depositing raw Raman and EXAFS data in a repository for reproducibility.

Simulated Author's Rebuttal

6 responses · 1 unresolved

We thank the referee for a careful and constructive reading of our manuscript. The experimental methodology is acknowledged as sound, and the referee recognizes the genuine contribution of observing Fano line shapes, excitation-energy-independent continuum, and correlated EXAFS anomalies in a 3d cobaltate. The central concern raised—that crystal-field excitations of the Co²⁺ ⁴T₁ multiplet have not been ruled out as the source of the Fano continuum—is a valid and important point. Below we address this and the other issues raised.

read point-by-point responses

  1. Referee: MAJOR COMMENT — §IV, elimination chain, step (3): Crystal-field excitations of the Co²⁺ (d⁷) ⁴T₁ multiplet, split by spin-orbit coupling into a Kramers doublet ground state plus excited quartet and sextet states, are a well-known source of Fano line shapes and broad continua in insulating transition-metal oxides. Phonon coupling to these crystal-field levels is not discussed or ruled out. This is a load-bearing gap: if the continuum originates from crystal-field excitations rather than magnetic fluctuations, the central claim of 'proximate Kitaev-like correlations' does not follow. The authors should either estimate the expected crystal-field excitation energies and Raman response from these levels, or otherwise address this alternative.

    Authors: We agree with the referee that this is a critical gap in our argument and that crystal-field excitations within the spin-orbit-split ⁴T₁ multiplet of Co²⁺ must be explicitly addressed. We will revise the manuscript to incorporate this discussion. Our response is organized as follows: (i) we estimate the expected crystal-field excitation energies, (ii) we discuss why several features of our data are nevertheless more naturally explained by magnetic fluctuations, and (iii) we acknowledge that crystal-field excitations cannot be definitively excluded without further measurements, and we will adjust our claims accordingly. revision: partial

  2. Referee: (Continuation of above — estimate of crystal-field excitation energies)

    Authors: For Co²⁺ (3d⁷) in an octahedral crystal field with a ⁴T₁ ground term, the effective orbital angular momentum is L̃ = 1 and the spin is S = 3/2. The spin-orbit coupling within the ⁴T₁ term is characterized by an effective coupling constant λ_eff = −λ/2, where λ ≈ −180 cm⁻¹ is the free-ion spin-orbit coupling constant for Co²⁺. This yields λ_eff ≈ 90 cm⁻¹. The ⁴T₁ multiplet then splits into states labeled by J̃ = |L̃ − S|, ..., L̃ + S: a ground-state doublet (J̃ = 1/2), a first excited quartet (J̃ = 3/2) at approximately 3λ_eff ≈ 270 cm⁻¹ above the ground state, and a second excited sextet (J̃ = 5/2) at approximately 5λ_eff ≈ 450 cm⁻¹. These are rough estimates; covalency, the trigonal distortion of the monoclinic P2₁/n structure, and the non-cubic crystal field will modify these values. Nevertheless, the first excited quartet is expected in the range ~150–300 cm⁻¹, which overlaps with the energies of the Fano modes S4–S6 (~140–180 cm⁻¹) and the low-energy continuum. We acknowledge that phonon coupling to these crystal-field levels could in principle produce Fano line shapes and a continuum in the same spectral region we observe. This is a legitimate alternative explanation that our manuscript does not currently address, and we will add a dedicated discussion of this point in the revised manuscript. revision: yes

  3. Referee: (Continuation — arguments favoring magnetic origin despite crystal-field alternative)

    Authors: While we cannot definitively rule out crystal-field excitations, we note several features of our data that are more naturally explained by magnetic fluctuations: (1) The quasielastic scattering centered at ω = 0, which persists from 12 K to 300 K and shows non-monotonic temperature dependence (decreasing from 12 to ~60 K, increasing to ~120 K, then decreasing), is characteristic of relaxational spin dynamics rather than crystal-field excitations, which would produce inelastic scattering at finite energy transfer. (2) The Fano asymmetry parameter q for modes S4 and S6 shows an abrupt jump near 160 K, which correlates with the bifurcation of ZFC/FC magnetization curves and a hump in magnetic susceptibility reported in Ref. [35]. Crystal-field excitations would not be expected to show such a correlation with bulk magnetic anomalies. (3) The broad continuum persists into the magnetically ordered phase at 12 K without evolving into well-defined two-magnon peaks, which is more consistent with fractionalized or short-range magnetic fluctuations than with discrete crystal-field levels that would sharpen at low temperature. (4) The correlated EXAFS anomalies (changes in Debye–Waller factors and bond distances) at the same temperatures where Raman anomalies occur suggest magnetostrictive coupling, which links lattice and spin degrees of freedom rather than lattice and crystal-field levels. We will incorporate these arguments into the revised discussion while being explicit about their qualitative nature. revision: yes

  4. Referee: SIGNIFICANCE — Absence of any quantitative comparison to the predicted Kitaev Raman response (unlike in 5d iridate analogues)

    Authors: The referee is correct that we do not provide a quantitative comparison to the theoretically predicted Kitaev Raman response. This is a limitation of the present work. In 5d iridate analogues such as α-RuCl₃ and A₂ZnIrO₆, such comparisons have been facilitated by the availability of calculated Raman response functions for the Kitaev model on specific lattices. For the d⁷ cobalt system on the fcc sublattice of SrLaCoNbO₆, the theoretical framework of Liu and Khaliullin (Ref. [34]) predicts the possibility of Kitaev-type interactions but does not provide a calculated Raman response function that we could directly compare to. We will add a statement in the revised manuscript acknowledging this limitation explicitly and noting that a quantitative comparison awaits theoretical calculations of the Raman response for the d⁷ fcc case. We will also temper our language from 'consistent with proximate Kitaev-like correlations' to make clear that this is a qualitative consistency, not a quantitative demonstration. revision: yes

  5. Referee: SIGNIFICANCE — Failure to rule out crystal-field excitations as the source of the Fano continuum

    Authors: This is the same issue raised in the major comment above. We agree it must be addressed and will do so as described in our responses above. We will add a paragraph in §IV explicitly discussing crystal-field excitations within the ⁴T₁ multiplet, estimating their expected energies, noting the spectral overlap with our observed features, and explaining why we still favor a magnetic interpretation while acknowledging that crystal-field contributions cannot be excluded without inelastic neutron scattering or other direct probes. revision: yes

  6. Referee: SIGNIFICANCE — No falsifiable predictions or machine-checked results; EXAFS fitting is standard but not reproducible from the manuscript alone (data not publicly available)

    Authors: We agree that the EXAFS data are not currently publicly available. We will deposit the raw and processed EXAFS data (k³χ(k) spectra and Fourier-transformed χ(R) data at all measured temperatures) in a public repository and update the Data Availability statement accordingly. Regarding falsifiable predictions: we will add a statement that inelastic neutron scattering measurements should reveal either (a) a broad continuum of magnetic scattering consistent with fractionalized excitations, or (b) discrete crystal-field excitations at ~150–300 cm⁻¹, which would distinguish between the two scenarios. This makes the central claim testable by a specific experiment. revision: yes

standing simulated objections not resolved
  • We cannot definitively rule out crystal-field excitations of the Co²⁺ ⁴T₁ multiplet as a source of the Fano continuum without inelastic neutron scattering or equivalent direct spectroscopic probes. The estimated crystal-field excitation energies (~150–300 cm⁻¹ for the first excited quartet) overlap with the observed Fano modes and continuum. While we argue that the quasielastic response, correlation with magnetic susceptibility anomalies, and EXAFS evidence for magnetostriction favor a magnetic interpretation, we acknowledge this is not a definitive exclusion.

Circularity Check

0 steps flagged · score 0.0 of 10

No circularity: the paper's argument is inference by elimination and analogy, not a derivation that reduces to its inputs

full rationale

The paper observes Raman anomalies (Fano line shapes, broad continuum, phonon self-energy renormalization) and EXAFS structural changes, then argues by elimination and analogy that these are 'consistent with' Kitaev-like magnetic correlations. No step in this chain reduces to its inputs by construction. The Fano parameters (Eq. 1) and anharmonic model parameters (Eqs. 2-3) are fitted from data and reported as measurements, not predictions. The load-bearing theoretical premise — that d7 Co2+ systems can host Kitaev interactions — comes from Liu & Khaliullin (Ref. 34), an independent theoretical work by authors not on this paper. Self-citations (Refs. 35, 36, 39, 58, 59) provide experimental characterization of the same material (synthesis, magnetization, neutron diffraction, EXAFS), not theoretical premises that would make the argument circular. The paper repeatedly hedges its claims ('consistent with,' 'suggests,' 'cannot be excluded,' 'difficult to ascertain whether... solely drive... or whether... purely structural'). The identified weaknesses — crystal-field excitations not ruled out as Fano continuum source, no quantitative comparison to predicted Kitaev Raman response — are correctness/interpretation risks, not circularity. The derivation is self-contained against external benchmarks (comparison to 5d iridate systems from independent groups, standard EXAFS fitting procedures, standard anharmonic phonon model).

Assumptions & free parameters 7 free parameters · 4 assumptions · 1 invented entities

The paper introduces no new entities. The free parameters are all standard fitting parameters for Raman phonon analysis and EXAFS modeling. The key axioms are domain assumptions about the electronic structure of Co2+ and interpretive choices about the origin of spectroscopic features.

free parameters (7)
  • A (anharmonic frequency coefficient) = varies by mode, listed in Table S2
    Fitting parameter in the three-phonon anharmonic decay model (Eq. 2), used to establish the baseline from which phonon anomalies are identified as deviations.
  • B (anharmonic linewidth coefficient) = varies by mode, listed in Table S2
    Fitting parameter in the anharmonic linewidth model (Eq. 3), used to establish baseline phonon linewidth behavior.
  • ω0 (bare phonon frequency at 0 K) = varies by mode
    Fitting parameter in Eqs. 2 and 3 for each phonon mode.
  • Γ0 (bare linewidth at 0 K) = varies by mode
    Fitting parameter in Eq. 3 for each phonon mode.
  • q (Fano asymmetry parameter) = temperature-dependent, varies by mode S4-S6
    Fitting parameter in the Fano profile (Eq. 1) for low-energy modes; its temperature evolution is a key observational result.
  • S0^2 (EXAFS amplitude reduction factor) = determined at 21 K, then fixed
    EXAFS fitting parameter fixed from lowest-temperature fit and held constant at all other temperatures.
  • E0 (EXAFS energy shift) = determined at 21 K, then fixed
    EXAFS fitting parameter fixed from lowest-temperature fit.
assumptions (4)
  • domain assumption Co2+ in SrLaCoNbO6 has a 4T1 ground term with a Kramers doublet ground state giving pseudospin S̃ = 1/2
    Stated in Introduction and Section IV, based on Refs. 32-36. This is the prerequisite for Kitaev exchange in d7 systems per Liu & Khaliullin (Ref. 34). The crystal field splitting is described as 'relatively weak' preserving 4T1 character.
  • ad hoc to paper The broad low-energy Raman continuum is magnetic in origin
    Section IV: luminescence ruled out by excitation-energy independence, electronic ruled out by insulating nature, magnons ruled out by persistence into ordered phase. Magnetic fluctuations are the remaining explanation by elimination, but no direct magnetic measurement confirms this.
  • ad hoc to paper The 60 K phonon anomalies reflect spin-lattice coupling rather than purely structural effects
    Section IV: 'a purely structural contribution cannot be excluded.' No magnetization or specific heat anomaly at 60 K. Neutron diffraction shows no structural transition. The attribution to magnetic correlations is an inference, not a demonstrated fact.
  • standard math The three-phonon anharmonic model (Eqs. 2-3) is the correct baseline for identifying anomalous phonon behavior
    Standard Balkanski-Wallis-Haro model (Ref. 47), widely used in Raman spectroscopy. Deviations from this model define the 'anomalies' that the paper interprets.
invented entities (1)
  • None
    purpose: N/A
    The paper does not invent new particles, forces, or entities. It interprets existing spectroscopic features within the established Kitaev framework from prior theory (Ref. 34). No new postulated objects.

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Cite this review

Pith. "Pith review of Raman spectroscopic signature of Kitaev magnetism and complex spin-lattice coupling in S = 1/2 antiferromagnet SrLaCoNbO$_6$ double perovskite." pith.science (2026). https://pith.science/paper/5GKP7K3L

@misc{pith2026260707630,
  author       = {Pith},
  title        = {Pith review of: Raman spectroscopic signature of Kitaev magnetism and complex spin-lattice coupling in S = 1/2 antiferromagnet SrLaCoNbO$_6$ double perovskite},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/5GKP7K3L}},
  note         = {Machine review of arXiv:2607.07630}
}
abstract

We report a detailed analysis of temperature-dependent Raman spectroscopy and Co $K$-edge extended x-ray absorption fine structure (EXAFS) for a pseudospin-$\tilde{S}=1/2$ insulating antiferromagnet SrLaCoNbO$_6$, a B-site--ordered double perovskite hosting Co$^{2+}$ ($3d^7$) ions on an {\it f.c.c.} sublattice. Notably, pronounced anomalies in the phonon frequency, linewidth and spectral weight are observed around 60~K, well above the long-range antiferromagnetic transition at $T_{\rm N} \approx 15$~K. These renormalizations indicate a significant coupling between lattice and spin degrees of freedom, although a purely structural contribution cannot be excluded. Additional modifications of both high- and low-energy Raman modes are detected near 160-180 K, including changes in linewidth and intensity, variations of the Fano asymmetry parameter, and the emergence of an additional low-energy feature. The asymmetric Fano line shape of selected low-energy modes, together with a broad low-energy continuum and quasielastic response, suggests coupling between discrete phonons and fluctuating magnetic excitations. Moreover, the EXAFS analysis reveals correlated changes in bond distances and Debye-Waller factors around the Co ions near 60~K and 160~K, evidencing subtle local structural distortions and possible magnetostrictive effects. The persistence of anomalous lattice dynamics far above $T_{\rm N}$, combined with the excitation-energy--independent continuum, is consistent with fluctuating bond-directional interactions and proximate Kitaev-like correlations.

Figures

Figures reproduced from arXiv: 2607.07630 by the authors.

Figure 1
Figure 1. FIG. 1. (a) The Raman spectra of SrLaCoNbO [PITH_FULL_IMAGE:figures/full_fig_p003_1.png] view at source ↗
Figure 2
Figure 2. FIG. 2. Temperature dependence of the (a–c) phonon fre [PITH_FULL_IMAGE:figures/full_fig_p004_2.png] view at source ↗
Figure 3
Figure 3. FIG. 3. (a) Contour plot of the Raman spectra of [PITH_FULL_IMAGE:figures/full_fig_p004_3.png] view at source ↗
Figures from the paper (4 more)
Figure 4
Figure 4. Figure 4: FIG. 4. Fits to the S4-S6 modes of the Raman spectrum at 12 K using the sum of (a) Voigt (b) Fano line shapes. (c–e) [PITH_FULL_IMAGE:figures/full_fig_p005_4.png]
Figure 5
Figure 5. Figure 5: FIG. 5. (a–f) Temperature dependence of the phonon frequencies of modes S4–S7, S14, and S15, respectively. The solid black [PITH_FULL_IMAGE:figures/full_fig_p006_5.png]
Figure 6
Figure 6. Figure 6: FIG. 6. (a–c) Raman spectra of SrLaCoNbO [PITH_FULL_IMAGE:figures/full_fig_p007_6.png]
Figure 7
Figure 7. Figure 7: FIG. 7. (a) Temperature-dependent magnitude of the Fourier-transformed [PITH_FULL_IMAGE:figures/full_fig_p008_7.png]

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Pith tools

Reviewed July 9, 2026 · model on record in the stance chip above.