Temporal and spatial separations between spin glass and short-range order

Feng Ye; Margarita G. Dronova; Yejun Feng; Yishu Wang; Zachary J. Morgan

arxiv: 2507.07783 · v1 · pith:T63KLZJKnew · submitted 2025-07-10 · ❄️ cond-mat.dis-nn · cond-mat.str-el

Temporal and spatial separations between spin glass and short-range order

Margarita G. Dronova , Feng Ye , Zachary J. Morgan , Yishu Wang , Yejun Feng This is my paper

Pith reviewed 2026-05-25 07:36 UTC · model grok-4.3

classification ❄️ cond-mat.dis-nn cond-mat.str-el

keywords spin glassshort-range orderdisorder tuningspinelneutron scatteringheat capacitydomain wallsmagnetic order

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The pith

Spin glass coexists uncorrelated with short- and long-range order in a disorder-tuned spinel, with glass components from spins at cluster domain walls.

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

The paper tunes disorder on a spinel sublattice to create specimens that evolve from long-range magnetic order and then compares their behavior across long (milliseconds to seconds) and short (picosecond) time scales. Neutron magnetic diffuse scattering shows that the dynamics of short- and long-range order formation remain unchanged by disorder, while the spatial ranges of those orders are altered. The inflection point in the temperature dependence of the correlation length matches the heat capacity peak in every specimen, yet spin glass freezing can occur either below or well above this temperature. These observations establish an uncorrelated coexistence between the spin glass and the ordered states, with the glass attributed to individual spins at domain walls between spin clusters.

Core claim

By introducing controlled disorder on the spinel sublattice and cross-referencing long and short time scale measurements, the study shows that the dynamics of short- and long-range order formations are unaffected by disorder while their ranges change, the inflection point of the correlation length temperature dependence matches the heat capacity peak across all specimens, and spin glass can freeze either below or well above this characteristic temperature, identifying an uncorrelated coexistence in which components of the spin glass are attributed to individual spins at domain walls between spin clusters.

What carries the argument

Controlled disorder tuning on the spinel sublattice together with cross-referencing of millisecond-to-second and picosecond measurements that isolates spin glass dynamics from order formation.

If this is right

The spatial ranges of short- and long-range orders change with added disorder while their formation dynamics stay constant.
The temperature at which order forms, marked by the heat capacity peak and correlation length inflection, is independent of the spin glass freezing temperature.
Spin glass freezing can occur either below or well above the characteristic temperature of spin order formation.
Components of the spin glass arise specifically from individual spins located at domain walls between spin clusters.

Where Pith is reading between the lines

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

The same domain-wall mechanism could be tested in other frustrated magnets by applying comparable disorder tuning and time-scale cross-referencing.
Independent control of glassy and ordered phases might be possible in materials where domain walls can be engineered separately from bulk order.
Extending the approach to systems with different lattice geometries could reveal whether uncorrelated coexistence is general or specific to spinel chemistry.

Load-bearing premise

That cross-referencing long and short time scale measurements on a series of disorder-tuned specimens cleanly separates spin glass dynamics from order formations without confounding effects from the specific spinel chemistry or measurement techniques.

What would settle it

A direct observation, such as neutron scattering or susceptibility data on additional samples, showing that spin glass freezing temperature always tracks the heat capacity peak or that domain wall regions carry no distinct glassy signal.

Figures

Figures reproduced from arXiv: 2507.07783 by Feng Ye, Margarita G. Dronova, Yejun Feng, Yishu Wang, Zachary J. Morgan.

**Figure 1.** Figure 1: Disparate phase behaviors of Zn(Fe,Ga)2O4. (A-D) DC magnetic susceptibility 𝜒('(𝑇) and heat capacity 𝐶D(𝑇) of Zn(FexGa1-x)2O4 are plotted in the same panel to illustrate the evolving difference between two characterization techniques. No lattice heat capacity is subtracted from 𝐶D. (E) The respective peak temperatures 𝑇$%& (blue) and 𝑇' (red) of 𝜒('(𝑇) and 𝐶D(𝑇) are plotted as a function of Fe concentratio… view at source ↗

**Figure 2.** Figure 2: Evolution of the imaginary AC magnetic susceptibility. 𝜒"(𝑇) were measured for pure ZnFe2O4 grown from (A) 𝑇)=850 o C and (B) 𝑇)=1000 o C respectively, and Zn(FexGa1- [PITH_FULL_IMAGE:figures/full_fig_p012_2.png] view at source ↗

read the original abstract

Broken-symmetry-induced order parameters account for many phenomena in condensed matter physics. For spin glasses, such a framework dictates its theoretical construction, whereas experiments have only established dynamical behaviors such as frequency dependent magnetic susceptibility and aging but not the thermodynamic phase. Experimental techniques have limitations when the spin glass is probed as an isolated state. To resolve this conundrum, we create an evolution from long-range order using a well-controlled tuning of the disorder on a spinel's sublattice. Cross-referencing a series of specimens at both long (milliseconds to seconds) and short (picosecond) time scales illustrates the relationship between spin glass and long- and short-range orders. The dynamics of short- and long-range order formations are not affected by disorder, as revealed by neutron magnetic diffuse scattering, however the ranges of these orderings are changed by the introduced disorder. Across all specimens, the inflection point of the correlation length's temperature dependence fully matches with the peak in heat capacity, while spin glass can freeze either below or well above this characteristic temperature of spin order formation. Our results identify an uncorrelated coexistence of the two and attribute components of the spin glass to individual spins at domain walls between spin clusters.

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.

Desk Editor's Note private letter to a colleague

Spin glass freezing can sit above or below short-range order formation in disorder-tuned spinels, with the decoupling tied to domain walls, but the time-scale separation needs tighter controls against material-specific effects.

read the letter

The paper's core observation is that across a series of spinel specimens with tuned sublattice disorder, the spin glass transition temperature can land either below or well above the inflection point in correlation length that matches the heat capacity peak. They attribute the glass component to individual spins at domain walls between clusters, arguing for uncorrelated coexistence rather than a single thermodynamic phase. Neutron diffuse scattering on the picosecond scale shows that disorder changes the spatial range of short- and long-range order but leaves the formation dynamics unchanged, while longer-time susceptibility tracks the glass freezing separately. This is the concrete new piece: temperature-independent glass behavior relative to order formation, backed by multiple specimens. The consistent match between correlation length inflection and heat capacity peak is a clean experimental result that holds up across the series. The soft spot is the inference of clean separation. The claim rests on cross-referencing millisecond-to-second susceptibility with picosecond neutron data, but the particular spinel chemistry or probe combination could introduce extra relaxation or pinning channels that the disorder series does not fully control. Without seeing the full error bars, specimen selection criteria, and any checks for technique-specific artifacts, it is hard to judge how general the decoupling is versus specific to this family. This is for condensed matter people working on disordered magnets and spin glasses. It engages the open question of whether spin glasses require an isolated thermodynamic description by trying to separate the phenomena experimentally. The work is straightforward enough that it deserves a serious referee to check the data quality and controls, even if the interpretation may need tightening.

Referee Report

2 major / 1 minor

Summary. The manuscript claims that tuning disorder on the spinel sublattice allows cross-referencing of neutron magnetic diffuse scattering (picosecond scale) with heat capacity and susceptibility (millisecond-to-second scale) across multiple specimens. It reports that order-formation dynamics remain disorder-independent while correlation lengths change, that the inflection in correlation length versus temperature matches the heat-capacity peak in all cases, and that the spin-glass freezing temperature can lie either below or well above this characteristic temperature, implying uncorrelated coexistence with spin-glass components localized to individual spins at domain walls between spin clusters.

Significance. If the experimental separation of timescales and disorder series holds without unaccounted confounds, the result would clarify the relationship between spin-glass dynamics and thermodynamic ordering by demonstrating their independence in a tunable system and linking the glass component to domain-wall spins. The multi-timescale, multi-specimen approach is a methodological strength that directly addresses the experimental limitations noted in the abstract.

major comments (2)

[Abstract] Abstract: the central claim that spin glass 'can freeze either below or well above' the order-formation temperature rests on the observed decoupling, yet the text provides no quantitative values, error bars, or explicit criteria for locating the glass transition in the susceptibility data for each specimen, leaving the 'either below or above' statement unverified.
[Abstract] Abstract: the inference of uncorrelated coexistence without chemistry- or technique-specific confounds assumes the disorder series cleanly isolates the phenomena, but no controls or cross-checks are described to rule out additional relaxation channels introduced by the particular spinel chemistry or the combination of neutron scattering and bulk probes.

minor comments (1)

[Abstract] Abstract: the number of specimens, the range of disorder levels, and the precise definition of 'inflection point' in the correlation length are not stated, which would aid reproducibility.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the careful reading and constructive comments on our manuscript. We address each point below and revise the abstract and discussion to improve quantitative clarity while maintaining that the disorder series and cross-probe consistency already provide strong support for the claims.

read point-by-point responses

Referee: [Abstract] Abstract: the central claim that spin glass 'can freeze either below or well above' the order-formation temperature rests on the observed decoupling, yet the text provides no quantitative values, error bars, or explicit criteria for locating the glass transition in the susceptibility data for each specimen, leaving the 'either below or above' statement unverified.

Authors: We agree that the abstract would be strengthened by explicit quantitative support. In the revised version we will add the specific spin-glass freezing temperatures (defined via the peak position in the imaginary susceptibility χ'' at 1 Hz, with uncertainties from multiple frequency extrapolations) for each specimen alongside the order-formation temperatures obtained from both the heat-capacity peak and the correlation-length inflection point. This will directly illustrate the cases of T_sg below and above the characteristic temperature while preserving the abstract's length. revision: yes
Referee: [Abstract] Abstract: the inference of uncorrelated coexistence without chemistry- or technique-specific confounds assumes the disorder series cleanly isolates the phenomena, but no controls or cross-checks are described to rule out additional relaxation channels introduced by the particular spinel chemistry or the combination of neutron scattering and bulk probes.

Authors: The tunable disorder series on the spinel sublattice, with fixed underlying chemistry, serves as the primary control: order-formation dynamics remain disorder-independent while correlation lengths vary systematically, and the inflection-point/heat-capacity match holds uniformly. The agreement between picosecond neutron diffuse scattering and millisecond-to-second bulk probes further indicates that additional relaxation channels are not dominant. Nevertheless, we will add an explicit paragraph in the discussion section that enumerates potential chemistry- or probe-specific confounds and explains why the observed disorder independence and cross-technique consistency rule them out. revision: partial

Circularity Check

0 steps flagged

No circularity: purely experimental claims from multi-specimen neutron and heat-capacity data

full rationale

The manuscript presents experimental results on disorder-tuned spinel specimens using neutron magnetic diffuse scattering (picosecond scale) and heat capacity/magnetic susceptibility (millisecond-second scale). The central claim of uncorrelated coexistence between spin glass and short-/long-range order is inferred directly from the observed mismatch between correlation-length inflection points and glass-transition temperatures across the disorder series. No equations, fitted parameters renamed as predictions, self-citations invoked as uniqueness theorems, or ansatzes are present in the provided text. The derivation chain consists solely of data comparison and does not reduce to its inputs by construction.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The work is experimental and relies on standard assumptions about magnetic scattering and thermodynamic signatures in disordered systems; no free parameters or invented entities are evident from the abstract.

axioms (1)

domain assumption Tuning disorder on the spinel's sublattice creates a controlled evolution from long-range order without introducing unrelated chemical or structural changes.
Invoked to justify the specimen series as a clean tuning parameter for separating spin glass from order.

pith-pipeline@v0.9.0 · 5752 in / 1229 out tokens · 26041 ms · 2026-05-25T07:36:59.278243+00:00 · methodology

discussion (0)

Reference graph

Works this paper leans on

2 extracted references · 2 canonical work pages · 1 internal anchor

[1]

M. J. P. Gingras, C. V. Stager, N. P. Raju, B. D. Gaulin, and J.E. Greedan, Static critical behavior of the spin-freezing transition in the geometrically frustrated pyrochlore antiferromagnet Y2Mo2O7. Phys. Rev. Lett. 78, 947-950 (1997). [14] A. P. Ramirez, and S. V. Syzranov, Short-range order and hidden energy scale in geometrically frustrated magnets. ...

work page 1997
[2]

Enhanced Performance Neutron Scattering Spectroscopy by Use of Correlation Techniques

F. Mezei, M. T. Caccamo, F. Migliardo, S. Magazù, Enhanced performance neutron scattering spectroscopy by use of correlation techniques, arXiv:1609.03287 (2016). [27] F. Ye, Y. Liu, R. Whitfield, R. Osborn, S. Rosenkranz, implementation of cross correlation for energy discrimination on the time-of-flight spectrometer CORELLI, J. Appl. Cryst. 51, 315-322 (...

work page internal anchor Pith review Pith/arXiv arXiv 2016

[1] [1]

M. J. P. Gingras, C. V. Stager, N. P. Raju, B. D. Gaulin, and J.E. Greedan, Static critical behavior of the spin-freezing transition in the geometrically frustrated pyrochlore antiferromagnet Y2Mo2O7. Phys. Rev. Lett. 78, 947-950 (1997). [14] A. P. Ramirez, and S. V. Syzranov, Short-range order and hidden energy scale in geometrically frustrated magnets. ...

work page 1997

[2] [2]

Enhanced Performance Neutron Scattering Spectroscopy by Use of Correlation Techniques

F. Mezei, M. T. Caccamo, F. Migliardo, S. Magazù, Enhanced performance neutron scattering spectroscopy by use of correlation techniques, arXiv:1609.03287 (2016). [27] F. Ye, Y. Liu, R. Whitfield, R. Osborn, S. Rosenkranz, implementation of cross correlation for energy discrimination on the time-of-flight spectrometer CORELLI, J. Appl. Cryst. 51, 315-322 (...

work page internal anchor Pith review Pith/arXiv arXiv 2016