Pith. sign in

REVIEW 3 major objections 4 minor 56 references

Ultrafast X-ray sonography reveals the spatial heterogeneity of the laser-induced magneto-structural phase transition in FeRh

T0 review · 3 major / 4 minor · reviewed 2026-08-06 · deepseek-v4-flash

Challenge this review Re-run · record.json Download PDF Read on arXiv ↗ Review JSON

Pith's one-line read Strain pulses launched by the driving laser act as an internal sonar probe, showing that FeRh's ferromagnetic phase nucleates at the surface in columnar domains roughly 30 nm wide that coalesce into a layer.

desk verdict A genuinely new spatial claim about FeRh nucleation, but the 30 nm column diameter and the scenario ranking rest on two disjoint models that are never checked in one self-consistent forward calculation. read the letter →

arxiv 2507.16638 v1 pith:6V4JLA5I submitted 2025-07-22 cond-mat.mtrl-sci

Maximilian Mattern , Angel Rodriguez-Fernandez , Roman Shayduk , Jon Ander Arregi , Vojtěch Uhlíř , Ulrike Boesenberg , Jörg Hallmann , Wonhyuk Jo
show 8 more authors
Aliaksandr Leonau Rustam Rysov James Wrigley Alexey Zozulya Stefan Eisebitt Anders Madsen Daniel Schick Jan-Etienne Pudell
This is my paper · ORCID
classification cond-mat.mtrl-sci PACS 61.05.cp75.30.Kz
keywords phasetransitionsheterogeneityultrafastX-raydiffractionsonographyFeRhmagneto-structuraltransitionstrainpulsesdomainnucleation
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 introduces ultrafast X-ray sonography: a propagating strain pulse, launched by the same laser that drives a phase transition, is used as a non-invasive structural probe that locates where in a thin film the new phase appears and how it spreads. Applied to the antiferromagnetic-to-ferromagnetic transition in FeRh, the method shows the ferromagnetic phase nucleating at the surface in narrow, vertically extended columnar domains with a diameter of roughly 30 nm, which then coalesce into a continuous layer. A sympathetic reader should care because this is the kind of three-dimensional, growth-resolved detail that ordinary ultrafast diffraction averages away, and because the picture reconciles the fast structural rise with the slower magnetization rise seen in earlier FeRh experiments. The approach is claimed to be sample-agnostic and applicable to any phase transition whose coexisting phases have distinguishable diffraction signatures.

What carries the argument

The central object is the phase-specific strain response induced by a propagating bipolar strain pulse. Because a layer's average strain is nonzero only while the compressive and expansive halves of the pulse are unbalanced inside it, the layer's Bragg peak shifts in a characteristic timing pattern, and that timing decodes the location of each phase: the phase thickness follows from $d_{\mathrm{phase}} = \Delta t_{\mathrm{phase}} / v_s$, and the volume fraction splits into thickness and in-plane coverage through $V_{\mathrm{phase}}(t) = D_{\mathrm{phase}}(t)\, A_{\mathrm{phase}}(t)$. In the FeRh experiment the optical pump simultaneously drives the phase transition and launches the strain pulse, so no dedicated transducer is needed. The quantitative scenario selection solves the linear one-dimensional elastic wave equation with thermophysical parameters calibrated on earlier measurements of the same sample, feeds the resulting strain into a dynamical X-ray scattering calculation, and averages incoherently over stochastic nucleation delays.

What would settle it

A real-space imaging measurement with nanometre resolution — for example single-shot coherent X-ray imaging or time-resolved X-ray nanodiffraction on the same FeRh film at the same $7.7\,\text{mJ cm}^{-2}$ fluence — that directly shows whether the ferromagnetic phase appears as roughly 30 nm wide columnar domains at the surface that coalesce into a layer, or instead as a uniform surface layer or as full-thickness columns. A second check would vary the film's mosaic grain size and test whether the inferred domain diameter follows the grain size, confirming that the 30 nm value is set by microstructure.

Watch

Extended reading notes

Core claim

On the paper's own terms, the discovery is that the ferromagnetic phase of FeRh created by an intense femtosecond laser pulse does not appear as a uniform surface layer, nor as columns spanning the full film thickness, but as narrow columnar domains about 30 nm in diameter that nucleate in the near-surface region and later merge into a continuous layer. This identification comes from comparing the full experimental sonogram — diffracted X-ray intensity as a function of both delay time and out-of-plane reciprocal coordinate — with simulated sonograms for five distinct nucleation scenarios; a global $\chi^2$ analysis selects the near-surface-column scenario (III) across all pump-probe delays, and the same scenario fits three of the four laser fluences studied, while the lowest fluence leaves the film laterally heterogeneous with partial in-plane coverage. The paper further finds that the depth of the ferromagnetic phase tracks the depth at which the optical excitation overcomes the equilibrium transition threshold, revealing the thermal character of the transition even on its non-equilibrium pathway.

Load-bearing premise

The scenario ranking and the roughly 30 nm column diameter stand on a one-dimensional elastic model whose thermophysical parameters were calibrated in earlier experiments on the same sample — including the choice to ignore the bottommost 5.5 nm of the FeRh layer — and on the assumption that the extra broadening of the ferromagnetic Bragg peak comes entirely from in-plane expansion as captured by a simplified five-site stochastic model.

Editorial extensions

If this is right

  • The conflicting FeRh observations in the literature are reconciled: the structural Bragg signal rises on the 8 ps nucleation timescale because near-surface columnar formation changes lattice volume quickly, while the macroscopic magnetization rises more slowly because the freshly nucleated domains start with magnetization along different magnetic easy axes and only align later through domain-wall
  • Because the pump that drives the transition also launches the probing strain pulse, the method needs no added transducer and almost no sample preparation, and it works for any material whose coexisting phases give distinguishable diffraction signatures.
  • The fluence series shows the non-equilibrium pathway still obeys a thermal logic: the near-surface extent of the ferromagnetic phase equals the depth at which the optical excitation crosses the equilibrium transition threshold, and only the lowest studied fluence leaves the film laterally heterogeneous with partial in-plane coverage.
  • The similar sizes of the nucleating ferromagnetic domains (about 30 nm) and the film's mosaic crystallites (about 25 nm) point to structural granularity as a key factor controlling where and how fast long-range ferromagnetic order emerges.

Reading between the lines

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

  • Because the depth information is carried by the strain-pulse transit time, the technique will discriminate best in films whose thickness is comparable to or larger than the pulse's spatial extent; for a few-nanometre layer the sonogram would essentially collapse, and the surface-versus-bulk distinction that carries the FeRh conclusion would be lost.
  • The match between the 30 nm domain diameter and the 25 nm mosaic grain size suggests a testable prediction the paper does not make: engineering the grain size of FeRh films through substrate choice, annealing, or ion bombardment should move the inferred column diameter, which would show that the value is set by microstructure rather than by intrinsic physics.
  • The broken-in-plane-symmetry argument — heterogeneous nucleation unlocks an in-plane expansion that broadens the out-of-plane Bragg peak — could serve as a general, probe-agnostic indicator of lateral phase coexistence in other materials, even where the coexisting phases have nearly identical out-of-plane lattice constants.
  • If the FeRh picture is correct, reported 'switching speeds' of magnetostructural transitions can differ by an order of magnitude depending on whether the probe reads lattice volume or magnetization; comparing the two signals is itself a diagnostic of near-surface columnar nucleation in other magnetic materials.
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 / 4 minor

Summary. The paper introduces ultrafast X-ray sonography, a pump-probe technique that combines time-resolved hard-X-ray diffraction with laser-launched strain pulses to image the spatial heterogeneity of a laser-induced phase transition. The method is demonstrated on the antiferromagnetic-to-ferromagnetic transition in a 44 nm FeRh film. The authors compare measured sonograms with one-dimensional elastic simulations for five nucleation scenarios and, using a global chi-square residual, select scenario III: the FM phase nucleates as columns in the near-surface region and coalesces into a continuous layer. They then estimate the in-plane domain diameter to be approximately 30 nm from an additional FM Bragg peak broadening that is not captured by their 1D model, using a separate five-site stochastic model. The fluence dependence of the scenario selection is also presented, showing scenario III for fluences above 5.2 mJ/cm2 and scenario IV for the lowest fluence.

Significance. If correct, this work introduces a broadly applicable and minimally invasive method for probing nanoscale phase heterogeneity in ultrafast phase transitions, and it offers a way to reconcile conflicting FeRh results in the literature. The strength of the paper is that the scenario comparison is a genuine model selection against measured intensity maps, not forced by construction, and the fluence-dependent consistency provides a meaningful internal check. The principal weakness is that the quantitative support for the headline 30 nm domain size is obtained from a different forward model than the one used to rank the scenarios, and the model used for ranking is explicitly incomplete in exactly the channel used for the size estimate. This is a load-bearing issue for the central claim, but it is testable and addressable within the scope of the manuscript.

major comments (3)
  1. [Modelling of sonograms / Estimating the in-plane domain dimension] The central claim — FM nucleates in near-surface columns of about 30 nm diameter — is assembled from two disjoint forward models. The sonogram simulations used for the global chi-square ranking (Fig. 4d) are produced by udkm1Dsim, a 1D elastic model in which lateral heterogeneity enters only through incoherent averaging over coverage, not through in-plane lattice expansion; the Methods explicitly state that the additional FM Bragg peak broadening 'is not captured by our modelling.' That same residual broadening is then used to infer the 30 nm diameter in a separate 5-site stochastic model. Consequently, the 30 nm parameter has no effect on the simulated I(t,qz) used to select scenario III, and the unmodeled broadening contributes to the chi-square residual as a missing signal rather than as a model prediction. There is no self-consistent check that the geometry of scenario III plus 30 nm domains reproduces the complete measured I(t,qz). I request that the authors either incorporate the in-plane broadening into the forward model and re-run the scenario comparison, or demonstrate explicitly that the scenario ranking is unchanged when the FM peak broadening is excluded from or added to the residual.
  2. [Ultrafast domain nucleation in FeRh / Fig. 4] The 'global residual χ2' is a sum of squared normalized-intensity differences without an explicit noise model. The measured I(t,qz) is presented as a single train-averaged curve, and no error bars or confidence bands are provided. The paper asserts that the global analysis 'identifies scenario III to optimally describe' the data, but without a statistical measure (e.g., a reduced chi-square with estimated uncertainties or a likelihood-ratio test between scenarios), the separation between scenarios I, III, and IV may not be significant. Given that the distinction hinges on subtle FM-peak position shifts at early delays, please provide an uncertainty estimate for the chi-square values or otherwise quantify whether the scenario ranking is robust to data noise.
  3. [Modelling of sonograms] The scenario ranking relies on a calibrated 1D elastic model whose free choices are not fully sensitivity-tested. The Methods state 'we use essentially the already calibrated parameters [26,34]' and 'only the optical penetration depth is optimised,' while also introducing an ad hoc assumption that the bottom-most 5.5 nm of FeRh does not contribute to the Bragg peak. Other parameters, such as the 0.6% phase-expansion amplitude, the fixed nucleation time τ=8 ps, and the scenario-IV thickness coefficient, enter the simulation. I ask for a sensitivity analysis showing how the scenario ranking and the inferred V*FM values in Fig. 4d and Extended Data Fig. E3 respond to plausible variations of these parameters; without it, the quantitative support for scenario III as the unique optimum is not fully established.
minor comments (4)
  1. [Methods (Sample growth and characterisation)] The sentence 'It is the very same same sample as in a previous publication [18]' contains a duplicated word ('same same') that should be corrected.
  2. [Fig. 4a] The axis label in Fig. 4a reads 'qz (Å)' but should be 'qz (Å⁻¹)' to be consistent with the rest of the text and figures.
  3. [Extended Data Fig. E3 caption] The phrase 'even larger as scenario II' should read 'even larger than scenario II.'
  4. [Estimating the in-plane domain dimension] The estimate of the uncertainty (±10 nm) is based on two stated sources, but the text does not explain how the 0.06 Å⁻¹ broadening value itself is determined from the fitted width in Extended Data Fig. E1c; a brief description of that measurement would aid reproducibility.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity is found: the scenario ranking and the 30 nm domain-size estimate are data-matched forward-model results, not re-statements of the model inputs.

full rationale

The central derivation chain is self-contained in the sense required by the circularity check. Scenario III is selected by a global chi-square comparison of five independently parametrized spatial hypotheses against the measured intensity maps I(t,qz); the scenarios share only the fixed FM volume-fraction rise of Eq. (3), and none of the geometries is defined by the outcome that it is used to establish. The 30 nm domain diameter is not an input to the scenario-selection step: the paper states that the additional FM Bragg-peak broadening of 0.06 Å^-1 is 'not captured by our one-dimensional model', and the size is obtained by matching a separate five-site stochastic in-plane expansion model to that residual broadening. That is parameter estimation from data, not a prediction forced by construction. The paper's reliance on earlier self-citations for calibrated thermophysical parameters [26,34] and the 8 ps nucleation time [18,26,34] is also not circular under the stated rules: those calibrations come from prior weak-excitation experiments and from measurements of the FM volume-fraction rise, not from the phase-heterogeneity result claimed here, and no uniqueness theorem is imported from the authors' prior work. The skeptic's concern that the scenario-ranking model omits the in-plane broadening later used for the domain size is a genuine modeling-completeness and correctness risk, but it is not a circular reduction: the conclusion is not equivalent to its inputs, it is merely conditional on the adequacy of the forward model.

Assumptions & free parameters 6 free parameters · 6 assumptions · 0 invented entities

The central claim rests on a chain of modeling assumptions rather than direct real-space imaging. The only quantities fit or adjusted in this paper are the optical penetration depth, the inactive 5.5 nm layer, the scenario IV coefficient, and the matched domain diameter; the rest are transferred from prior calibrations. No new physical entities are introduced.

free parameters (6)
  • Optical penetration depth = optimized, value not stated
    Adjusted to account for the different incidence angle of the pump; it affects the deposited energy profile and therefore the simulated strain sonogram.
  • Inactive FeRh layer thickness = 5.5 nm
    The bottom 5.5 nm of the nominal 44 nm FeRh layer is assumed not to contribute to the Bragg peak 'for an overall better agreement' in the Methods.
  • Final FM volume fraction V*_FM at 7.7 mJ/cm2 = 0.46
    Determined from the experimental integrated intensities and used to constrain all scenarios through Eq. (3); central to the scenario ranking.
  • Nucleation timescale tau = 8 ps
    Transferred from prior FeRh experiments [18,26,34]; all scenarios assume this rise time, so an error in tau could change early-delay scenario rankings.
  • Scenario IV relative thickness coefficient = 1.3
    Ad hoc choice D_FM = 1.3 V*_FM to represent a laterally incomplete surface layer; it is a modeling choice rather than an optimized fit.
  • FM domain diameter = 30 nm with estimated uncertainty of 10 nm
    Matched to reproduce the additional FM Bragg peak broadening using a 5-site stochastic nucleation model; this is the paper's main spatial result.
assumptions (6)
  • domain assumption The linear 1D elastic wave equation implemented in udkm1Dsim accurately models the spatio-temporal strain in the FeRh/Pt/W/MgO heterostructure.
    All sonogram scenarios are generated by solving this equation in Methods. If nonlinearities, interface reflections, or 2D effects matter, the scenario ranking could change.
  • domain assumption Thermophysical parameters calibrated in prior experiments on the same sample transfer to this measurement.
    Methods states only the optical penetration depth is optimized and the other parameters come from earlier calibrations [18,26,34].
  • ad hoc to paper Neglected effects, such as electronic band structure changes, latent heat, reduced thermal expansion in the FM phase, and altered electron-phonon coupling, are minor.
    Methods explicitly lists these as neglected to reduce free parameters and asserts the identification does not depend decisively on the strain pulse shape. This is an unverified assumption.
  • domain assumption The FM volume fraction follows the single-exponential form V_FM(t) = V*_FM (1 - exp(-t/tau)) with tau = 8 ps.
    Eq. (3) is taken from prior FeRh work [18,26,34] and constrains every scenario in the model comparison.
  • domain assumption The 0.6% out-of-plane expansion associated with FM appearance is known and spatially uniform within nucleated domains.
    Introduced as a stress source in the model based on prior literature [26,32], and it directly shapes the simulated phase-specific strain response.
  • ad hoc to paper The additional FM Bragg peak broadening arises exclusively from in-plane expansion in a periodic 5-site domain network.
    The domain-size estimate uses a fundamental building block of 5 nucleation sites; the paper acknowledges this simplification and gives a 10 nm uncertainty.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Ultrafast X-ray sonography reveals the spatial heterogeneity of the laser-induced magneto-structural phase transition in FeRh." pith.science (2026). https://pith.science/paper/6V4JLA5I

@misc{pith2026250716638,
  author       = {Pith},
  title        = {Pith review of: Ultrafast X-ray sonography reveals the spatial heterogeneity of the laser-induced magneto-structural phase transition in FeRh},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/6V4JLA5I}},
  note         = {Machine review of arXiv:2507.16638}
}
abstract

Phase transitions are governed by both intrinsic and extrinsic heterogeneities, yet capturing their spatio-temporal dynamics remains a challenge. While ultrafast techniques track phase changes on femtosecond timescales, the spatial complexity and stochastic nature of the processes often remain hidden. Here, we present an experimental approach that combines well-established ultrafast hard-X-ray diffraction with a propagating strain pulse as a universal and non-invasive probe. This ultrafast X-ray sonography can capture the spatio-temporal phase heterogeneity in great detail by resolving the phase-specific strain response. We apply this approach to the antiferromagnetic-to-ferromagnetic magneto-structural phase transition in FeRh and identify the ferromagnetic phase to nucleate at the surface as narrow columnar domains of approximately $30\,\text{nm}$ diameter. Besides reconciling the diverse experimental results in the literature on FeRh, X-ray sonography offers a versatile platform for investigating a wide range of phase transitions accompanied by structural changes.

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

56 extracted references · 51 canonical work pages

  1. [1]

    Sci- ence 309(5732), 257–262 (2005) https://doi.org/10.1126/science.1107559

    Dagotto, E.: Complexity in strongly correlated electronic systems. Sci- ence 309(5732), 257–262 (2005) https://doi.org/10.1126/science.1107559

    doi:10.1126/science.1107559 2005

  2. [2]

    Science 267(5197), 476–483 (1995) https://doi.org/10.1126/science.267

    Seul, M., Andelman, D.: Domain shapes and patterns: the phenomenology of mod- ulated phases. Science 267(5197), 476–483 (1995) https://doi.org/10.1126/science.267. 5197.476

    work page doi:10.1126/science.267 1995

  3. [3]

    Nano Letters 18(6), 3449–3453 (2018) https://doi.org/10

    Vidas, L., G¨ unther, C.M., Miller, T.A., Pfau, B., Perez-Salinas, D., Mart ´ ınez, E., Schnei- der, M., G¨ uhrs, E., Gargiani, P., Valvidares, M., et al.: Imaging nanometer phase coexis- tence at defects during the insulator–metal phase transformation in VO 2 thin films by resonant soft x-ray holography. Nano Letters 18(6), 3449–3453 (2018) https://doi.o...

    work page 2018

  4. [4]

    Nature Physics 13(1), 80–86 (2017) https://doi.org/10.1038/ nphys3882

    McLeod, A., Van Heumen, E., Ramirez, J., Wang, S., Saerbeck, T., Guenon, S., Gold- flam, M., Anderegg, L., Kelly, P., Mueller, A., et al.: Nanotextured phase coexistence in the correlated insulator V 2O3. Nature Physics 13(1), 80–86 (2017) https://doi.org/10.1038/ nphys3882

    work page 2017

  5. [5]

    Science 298(5594), 805–807 (2002) https://doi.org/ 10.1126/science.1077346

    Zhang, L., Israel, C., Biswas, A., Greene, R., De Lozanne, A.: Direct observation of per- colation in a manganite thin film. Science 298(5594), 805–807 (2002) https://doi.org/ 10.1126/science.1077346

    work page doi:10.1126/science.1077346 2002

  6. [6]

    Scientific Reports 6(1), 22383 (2016) https://doi.org/10.1038/ srep22383

    Pressacco, F., Uhl ´ιˇ r, V., Gatti, M., Ben- dounan, A., Fullerton, E.E., Sirotti, F.: Sta- ble room-temperature ferromagnetic phase at the FeRh (100) surface. Scientific Reports 6(1), 22383 (2016) https://doi.org/10.1038/ srep22383

    work page 2016

  7. [7]

    Proceedings of the National Academy of Sciences 119(19), 2118597119 (2022) https://doi.org/10.1073/ pnas.2118597119

    Ahn, Y., Cherukara, M.J., Cai, Z., Bartlein, M., Zhou, T., DiChiara, A., Walko, D.A., Holt, M., Fullerton, E.E., Evans, P.G., et al.: X-ray nanodiffraction imaging reveals distinct nanoscopic dynamics of an ultra- fast phase transition. Proceedings of the National Academy of Sciences 119(19), 2118597119 (2022) https://doi.org/10.1073/ pnas.2118597119

    work page 2022

  8. [8]

    : Disentangling hetero- geneity and disorder during ultrafast sur- face melting of orbital order

    Monti, M., Siddiqui, K.M., Perez-Salinas, D., Agarwal, N., Bremholm, M., Li, X., Prabhakaran, D., Liu, X., Babich, D., Sander, M., et al. : Disentangling hetero- geneity and disorder during ultrafast sur- face melting of orbital order. arXiv preprint arXiv:2407.03013 (2024) https://doi.org/10. 48550/arXiv.2407.03013 11

    work page doi:10.48550/arxiv.2407.03013 2024

Show all 56 references
  1. [9]

    Nature Communications 6(1), 6849 (2015) https://doi.org/10.1038/ ncomms7849

    O’Callahan, B.T., Jones, A.C., Hyung Park, J., Cobden, D.H., Atkin, J.M., Raschke, M.B.: Inhomogeneity of the ultrafast insulator-to-metal transition dynamics of VO 2. Nature Communications 6(1), 6849 (2015) https://doi.org/10.1038/ ncomms7849

    2015

  2. [10]

    : Evidence for topological defects in a pho- toinduced phase transition

    Zong, A., Kogar, A., Bie, Y.-Q., Rohwer, T., Lee, C., Baldini, E., Erge¸ cen, E., Yil- maz, M.B., Freelon, B., Sie, E.J., et al. : Evidence for topological defects in a pho- toinduced phase transition. Nature Physics 15(1), 27–31 (2019) https://doi.org/10.1038/ s41567-018-0311-9

    2019

  3. [11]

    Nature Communications 3(1), 838 (2012) https://doi.org/10.1038/ncomms1837

    Lee, W.-S., Chuang, Y., Moore, R., Zhu, Y., Patthey, L., Trigo, M., Lu, D., Kirchmann, P., Krupin, O., Yi, M., et al.: Phase fluctu- ations and the absence of topological defects in a photo-excited charge-ordered nickelate. Nature Communications 3(1), 838 (2012) https://doi.or...

    2012 doi

  4. [12]

    Nature Physics 19(2), 215–220 (2023) https: //doi.org/10.1038/s41567-022-01848-w

    Johnson, A.S., Perez-Salinas, D., Siddiqui, K.M., Kim, S., Choi, S., Volckaert, K., Majchrzak, P.E., Ulstrup, S., Agarwal, N., Hallman, K., et al.: Ultrafast x-ray imaging of the light-induced phase transition in VO 2. Nature Physics 19(2), 215–220 (2023) https: //doi.org/10.1...

    2023 doi

  5. [13]

    Nature Physics, 1–6 (2024) https:// doi.org/10.1038/s41567-024-02474-4

    Johnson, A.S., Pastor, E., Batlle-Porro, S., Benzidi, H., Katayama, T., Pe˜ na Mu˜ noz, G.A., Krapivin, V., Kim, S., L´ opez, N., Trigo, M., et al.: All-optical seeding of a light- induced phase transition with correlated dis- order. Nature Physics, 1–6 (2024) https:// doi.org...

    2024 doi

  6. [14]

    Nature Materi- als 14(9), 883–888 (2015) https://doi.org/10

    F¨ orst, M., Caviglia, A., Scherwitzl, R., Mankowsky, R., Zubko, P., Khanna, V., Bromberger, H., Wilkins, S., Chuang, Y.- D., Lee, W., et al.: Spatially resolved ultra- fast magnetic dynamics initiated at a com- plex oxide heterointerface. Nature Materi- als 14(9), 883–888 (20...

    2015

  7. [15]

    Science 371(6527), 371–374 (2021) https://doi.org/ 10.1126/science.abd2774

    Danz, T., Domr¨ ose, T., Ropers, C.: Ultra- fast nanoimaging of the order parameter in a structural phase transition. Science 371(6527), 371–374 (2021) https://doi.org/ 10.1126/science.abd2774

    2021 doi

  8. [16]

    Nature Physics 20(11), 1778–1785 (2024) https://doi.org/10.1038/ s41567-024-02628-4

    Amano, T., Babich, D., Mandal, R., Guzman- Brambila, J., Volte, A., Trzop, E., Servol, M., Pastor, E., Alashoor, M., Larsson, J., et al.: Propagation of insulator-to-metal tran- sition driven by photoinduced strain waves in a mott material. Nature Physics 20(11), 1778–1785 (20...

    2024

  9. [17]

    Physical Review Letters 108(8), 087201 (2012) https://doi.org/10

    Mariager, S.O., Pressacco, F., Ingold, G., Caviezel, A., M¨ ohr-Vorobeva, E., Beaud, P., Johnson, S., Milne, C., Mancini, E., Moy- erman, S., et al.: Structural and magnetic dynamics of a laser induced phase tran- sition in FeRh. Physical Review Letters 108(8), 087201 (2012) h...

    2012

  10. [18]

    APL Materials 12(5) (2024) https://doi.org/ 10.1063/5.0206095

    Mattern, M., Jarecki, J., Arregi, J.A., Uhl ´ ıˇ r, V., R¨ ossle, M., Bargheer, M.: Speed limits of the laser-induced phase transition in FeRh. APL Materials 12(5) (2024) https://doi.org/ 10.1063/5.0206095

    2024 doi

  11. [19]

    Physical Review B 93, 054305 (2016) https://doi.org/10.1103/ PhysRevB.93.054305

    Randi, F., Vergara, I., Novelli, F., Espos- ito, M., Dell’Angela, M., Brabers, V.A.M., Metcalf, P., Kukreja, R., D¨ urr, H.A., Fausti, D., Gr¨ uninger, M., Parmigiani, F.: Phase separation in the nonequilibrium verwey transition in magnetite. Physical Review B 93, 054305 (2016...

    2016

  12. [20]

    Physical Review Letters 87, 237401 (2001) https://doi.org/10.1103/ PhysRevLett.87.237401

    Cavalleri, A., T´ oth, C., Siders, C.W., Squier, J.A., R´ aksi, F., Forget, P., Kief- fer, J.C.: Femtosecond structural dynam- ics in vo 2 during an ultrafast solid-solid phase transition. Physical Review Letters 87, 237401 (2001) https://doi.org/10.1103/ PhysRevLett.87.237401

    2001

  13. [21]

    Nano Let- ters 17(4), 2460–2466 (2017) https://doi.org/ 10.1021/acs.nanolett.7b00144 12

    Gatel, C., Fu, X., Serin, V., Eddrief, M., Etgens, V., Warot-Fonrose, B.: In depth spa- tially inhomogeneous phase transition in epi- taxial MnAs film on GaAs (001). Nano Let- ters 17(4), 2460–2466 (2017) https://doi.org/ 10.1021/acs.nanolett.7b00144 12

    2017 doi

  14. [22]

    Sci- ence 318(5851), 788–792 (2007) https://doi

    Baum, P., Yang, D.-S., Zewail, A.H.: 4D visu- alization of transitional structures in phase transformations by electron diffraction. Sci- ence 318(5851), 788–792 (2007) https://doi. org/10.1126/science.1147724

    2007 doi

  15. [23]

    Nature Materials 12(10), 882–886 (2013) https://doi.org/10.1038/NMAT3718

    De Jong, S., Kukreja, R., Trabant, C., Pon- tius, N., Chang, C., Kachel, T., Beye, M., Sor- genfrei, F., Back, C., Br¨ auer, B.,et al.: Speed limit of the insulator–metal transition in magnetite. Nature Materials 12(10), 882–886 (2013) https://doi.org/10.1038/NMAT3718

    2013 doi

  16. [24]

    Science 316(5823), 425–429 (2007) https://doi.org/ 10.1126/science.1138834

    Gedik, N., Yang, D.-S., Logvenov, G., Bozovic, I., Zewail, A.H.: Nonequilibrium phase transitions in cuprates observed by ultrafast electron crystallography. Science 316(5823), 425–429 (2007) https://doi.org/ 10.1126/science.1138834

    2007 doi

  17. [25]

    Nature Com- munications 13(1), 2998 (2022) https: //doi.org/10.1038/s41467-022-30591-2

    Li, G., Medapalli, R., Mentink, J., Mikhaylovskiy, R., Blank, T., Patel, S., Zvezdin, A., Rasing, T., Fuller- ton, E., Kimel, A.: Ultrafast kinetics of the antiferromagnetic-ferromagnetic phase transition in FeRh. Nature Com- munications 13(1), 2998 (2022) https: //doi.org/10....

    2022 doi

  18. [26]

    Advanced Functional Materials 34(32), 2313014 (2024) https://doi.org/10.1002/adfm.202313014

    Mattern, M., Pudell, J.-E., Arregi, J.A., Zl´ amal, J., Kalousek, R., Uhl ´ ıˇ r, V., R¨ ossle, M., Bargheer, M.: Accelerating the Laser- Induced Phase Transition in Nanostructured FeRh via Plasmonic Absorption. Advanced Functional Materials 34(32), 2313014 (2024) https://doi....

    2024 doi

  19. [27]

    Photoacoustics, 100503 (2023) https://doi.org/10.1016/j.pacs.2023.100503

    Mattern, M., Reppert, A., Zeuschner, S.P., Herzog, M., Pudell, J.-E., Bargheer, M.: Con- cepts and use cases for picosecond ultrasonics with x-rays. Photoacoustics, 100503 (2023) https://doi.org/10.1016/j.pacs.2023.100503

    2023

  20. [28]

    Applied Physics Letters 120(9), 092401 (2022) https://doi.org/10.1063/5.0080378

    Mattern, M., Reppert, A., Zeuschner, S.P., Pudell, J.-E., K¨ uhne, F., Diesing, D., Herzog, M., Bargheer, M.: Electronic energy trans- port in nanoscale Au/Fe hetero-structures in the perspective of ultrafast lattice dynam- ics. Applied Physics Letters 120(9), 092401 (2022) ht...

    2022 doi

  21. [29]

    Physical Review Letters 108(25), 257208 (2012) https://doi.org/10

    Gray, A., Cooke, D., Kr¨ uger, P., Bordel, C., Kaiser, A., Moyerman, S., Fullerton, E., Ueda, S., Yamashita, Y., Gloskovskii, A., et al.: Electronic structure changes across the metamagnetic transition in FeRh via hard X- ray photoemission. Physical Review Letters 108(25), 257...

    2012

  22. [30]

    Structural Dynamics 5(3), 034501 (2018) https://doi.org/10.1063/ 1.5027809

    Pressacco, F., Uhl ´ ıˇ r, V., Gatti, M., Nicolaou, A., Bendounan, A., Arregi, J.A., Patel, S.K., Fullerton, E.E., Krizmancic, D., Sirotti, F.: Laser induced phase transition in epitaxial FeRh layers studied by pump-probe valence band photoemission. Structural Dynamics 5(3), 0...

    2018

  23. [31]

    Physical Review B 77(18), 184401 (2008) https://doi.org/10

    Stamm, C., Thiele, J.-U., Kachel, T., Radu, I., Ramm, P., Kosuth, M., Min´ ar, J., Ebert, H., D¨ urr, H., Eberhardt, W., et al.: Antiferromagnetic-ferromagnetic phase transition in FeRh probed by x-ray mag- netic circular dichroism. Physical Review B 77(18), 184401 (2008) http...

    2008

  24. [32]

    Physical Review B 101(17), 174413 (2020) https://doi.org/10

    Arregi, J.A., Caha, O., Uhl ´ ıˇ r, V.: Evolu- tion of strain across the magnetostructural phase transition in epitaxial FeRh films on different substrates. Physical Review B 101(17), 174413 (2020) https://doi.org/10. 1103/PhysRevB.101.174413

    2020

  25. [33]

    I Gen- eral theory

    Avrami, M.: Kinetics of phase change. I Gen- eral theory. The Journal of chemical physics 7(12), 1103–1112 (1939) https://doi.org/10. 1063/1.1750380

    1939

  26. [34]

    Communica- tions Physics 8(1), 140 (2025) https: //doi.org/10.1038/s42005-025-02066-5

    Mattern, M., Zeuschner, S.P., R¨ ossle, M., Arregi, J.A., Uhl ´ ıˇ r, V., Bargheer, M.: Non-thermal electrons open the non-equilibrium pathway of the phase transition in FeRh. Communica- tions Physics 8(1), 140 (2025) https: //doi.org/10.1038/s42005-025-02066-5

    2025 doi

  27. [35]

    npj Spintronics 3(1), 5 (2025) https: 13 //doi.org/10.1038/s44306-024-00069-6

    Dolgikh, I., Blank, T., Buzdakov, A., Li, G., Prabhakara, K., Patel, S., Medapalli, R., Fullerton, E., Koplak, O., Mentink, J., et al.: Ultrafast emergence of ferromagnetism in antiferromagnetic FeRh in high magnetic fields. npj Spintronics 3(1), 5 (2025) https: 13 //doi.org/1...

    2025 doi

  28. [36]

    Nature Communications 12(1), 5088 (2021) https://doi.org/10.1038/ s41467-021-25347-3

    Pressacco, F., Sangalli, D., Uhl ´ ıˇ r, V., Kut- nyakhov, D., Arregi, J.A., Agustsson, S.Y., Brenner, G., Redlin, H., Heber, M., Vasilyev, D., et al.: Subpicosecond metamagnetic phase transition in FeRh driven by non-equilibrium electron dynamics. Nature Communications 12(1),...

    2021

  29. [37]

    Nature Communications 15(1), 4958 (2024) https: //doi.org/10.1038/s41467-024-48795-z

    Hamara, D., Strungaru, M., Massey, J.R., Remy, Q., Chen, X., Nava Antonio, G., Alves Santos, O., Hehn, M., Evans, R.F., Chantrell, R.W., et al.: Ultra-high spin emis- sion from antiferromagnetic FeRh. Nature Communications 15(1), 4958 (2024) https: //doi.org/10.1038/s41467-024-48795-z

    2024 doi

  30. [38]

    Nature Communications 14(1), 3619 (2023) https://doi.org/10.1038/ s41467-023-39103-2

    Kang, K., Omura, H., Yesudas, D., Lee, O., Lee, K.-J., Lee, H.-W., Taniyama, T., Choi, G.-M.: Spin current driven by ultrafast mag- netization of FeRh. Nature Communications 14(1), 3619 (2023) https://doi.org/10.1038/ s41467-023-39103-2

    2023

  31. [39]

    Structural Dynamics 8(1), 014302 (2021) https://doi.org/10.1063/4.0000040

    Zeuschner, S.P., Mattern, M., Pudell, J.-E., Reppert, A., R¨ ossle, M., Leitenberger, W., Schwarzkopf, J., Boschker, J.E., Herzog, M., Bargheer, M.: Reciprocal space slicing: A time-efficient approach to femtosecond x-ray diffraction. Structural Dynamics 8(1), 014302 (2021) ht...

    2021 doi

  32. [40]

    Journal of Synchrotron Radiation 28(2), 637–649 (2021) https://doi.org/10

    Madsen, A., Hallmann, J., Ansaldi, G., Roth, T., Lu, W., Kim, C., Boesenberg, U., Zozulya, A., M¨ oller, J., Shayduk, R., Scholz, M., Bartmann, A., Schmidt, A., Lobato, I., Sukharnikov, K., Reiser, M., Kazarian, K., Petrov, I.: Materials Imag- ing and Dynamics (MID) instrument...

    2021

  33. [41]

    Computer Physics Com- munications 266, 108031 (2021) https://doi

    Schick, D.: udkm1Dsim – a Python tool- box for simulating 1D ultrafast dynamics in condensed matter. Computer Physics Com- munications 266, 108031 (2021) https://doi. org/10.1016/j.cpc.2021.108031

    2021

  34. [42]

    Journal of Physics: Condensed Mat- ter 27(25), 256001 (2015) https://doi.org/10

    Baldasseroni, C., Bordel, C., Antonakos, C., Scholl, A., Stone, K., Kortright, J., Hellman, F.: Temperature-driven growth of antiferromagnetic domains in thin-film FeRh. Journal of Physics: Condensed Mat- ter 27(25), 256001 (2015) https://doi.org/10. 1088/0953-8984/27/25/256001

    2015

  35. [43]

    Advanced Optical Materials 12(26), 2400939 (2024) https://doi.org/10.1002/adom.202400939

    Zeuschner, S.P., Pudell, J.-E., Mattern, M., R¨ ossle, M., Herzog, M., Baldi, A., Askes, S.H.C., Bargheer, M.: Unveiling the Nanomorphology of HfN thin Films by Ultra- fast Reciprocal Space Mapping. Advanced Optical Materials 12(26), 2400939 (2024) https://doi.org/10.1002/adom...

    2024 doi

  36. [44]

    arXiv preprint arXiv:2406.06832 (2024) https://doi.org/10

    McClellan, J., Zong, A., Pham, K.H., Liu, H., Iton, Z.W., Guzelturk, B., Walko, D.A., Wen, H., Cushing, S.K., Zuerch, M.W.: Hidden cor- relations in stochastic photoinduced dynam- ics of a solid-state electrolyte. arXiv preprint arXiv:2406.06832 (2024) https://doi.org/10. 4855...

    2024 doi arXiv

  37. [45]

    Nature Communi- cations 12(1), 1239 (2021) https://doi.org/ 10.1038/s41467-021-21316-y

    Mariette, C., Lorenc, M., Cailleau, H., Col- let, E., Gu´ erin, L., Volte, A., Trzop, E., Bertoni, R., Dong, X., L´ epine, B., et al.: Strain wave pathway to semiconductor-to- metal transition revealed by time-resolved x-ray powder diffraction. Nature Communi- cations 12(1), 1...

    2021 doi

  38. [46]

    Nature Photonics 17(11), 984–991 (2023) https:// doi.org/10.1038/s41566-023-01305-x

    Liu, S., Grech, C., Guetg, M., Karabekyan, S., Kocharyan, V., Kujala, N., Lechner, C., Long, T., Mirian, N., Qin, W., et al.: Cas- caded hard X-ray self-seeded free-electron laser at megahertz repetition rate. Nature Photonics 17(11), 984–991 (2023) https:// doi.org/10.1038/s4...

    2023 doi

  39. [47]

    Journal of Modern Optics 58(16), 1391–1403 (2011) https://doi.org/10.1080/ 09500340.2011.586473

    Geloni, G., Kocharyan, V., and, E.S.: A novel self-seeding scheme for hard X-ray FELs. Journal of Modern Optics 58(16), 1391–1403 (2011) https://doi.org/10.1080/ 09500340.2011.586473

    2011

  40. [48]

    Fron- tiers in Physics 11 (2024) https://doi.org/ 10.3389/fphy.2023.1329378

    Sztuk-Dambietz, J., Rovensky, V., Klujev, A., Laurus, T., Trunk, U., Ahmed, K., Meyer, 14 O., M¨ oller, J., Parenti, A., Raab, N., Shay- duk, R., Sikorski, M., Ansaldi, G., B¨ osenberg, U., Luis, L.M., Muenich, A., Preston, T.R., Schmidt, P., Stern, S., Bean, R., Madsen, A., G...

    2024

  41. [49]

    18 4.20 4.22 q002−1 z (Å ) b Extended Data Fig. E1: Comparison of Bragg peak properties in experiment and model: a, The normalised intensity I of the fitted antiferromagnetic (AFM) and ferromagnetic (FM) Bragg peaks (symbols) as a function of delayt. The black solid line denot...

  42. [50]

    1 0.5 0.9 I 0 10 20 30 Delay, (ps)t AFM FMa 3.9 mJcm−2 AFM FMb 5.2 mJcm−2

  43. [51]

    15 4.20 4.25 qz (Å )−1 0 10 20 30 Delay, (ps)t AFM FMc 7.7 mJcm−2

  44. [52]

    E2: Fluence-dependent sonograms:The normalised diffracted X-ray inten- sity I as function of the out-of-plane reciprocal coordinate qz

    15 4.20 4.25 qz (Å )−1 AFM FMd 11.7 mJcm−2 Extended Data Fig. E2: Fluence-dependent sonograms:The normalised diffracted X-ray inten- sity I as function of the out-of-plane reciprocal coordinate qz. The position of the antiferromagnetic (AFM) and ferromagnetic (FM) structural B...

  45. [53]

    10 Global residual, χ 2 a 3.9 mJ cm−2 I II III IV 0.25 0.30 0.35 0.40 Final FM volume fraction, V F * M 0.04 0.07

  46. [54]

    10 Global residual, χ 2 b 5.2 mJ cm−2 0.39 0.43 0.47 0.51 Final FM volume fraction, V F * M 0.08

  47. [55]

    16 Global residual, χ 2 c 7.7 mJ cm−2 0.51 0.57 0.63 0.69 Final FM volume fraction, V F * M

  48. [56]

    16 0.21 0.26 0.31 Global residual, χ 2 d 11.7 mJ cm−2 Scenario: Extended Data Fig. E3: Quantitative analysis deviation model and experiment:The global residual χ2 as function of the final ferromagentic (FM) volume fractionV ∗ FM for the nucleation scenarios I, II, III and IV a...

Pith tools

Reviewed August 6, 2026 · model on record in the stance chip above.