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REVIEW 3 major objections 4 minor 66 references

3D Mapping of Defects and Moir\'e Corrugations via Electron Ptychography Atomic Coordinate Retrieval

T0 review · 3 major / 4 minor · reviewed 2026-08-15 · deepseek-v4-flash

Pith's one-line read The paper claims that a single tilted 30-second 4D-STEM acquisition plus a physics-informed refinement recovers all six atomic planes of twisted bilayer WSe2 with 5.3 pm out-of-plane accuracy.

desk verdict The z-accuracy claim is built from priors, but the qualitative 3D model and the mixed corrugation observation deserve attention and review. read the letter →

arxiv 2509.07140 v1 pith:TTSFDNBK submitted 2025-09-08 cond-mat.mtrl-sci

classification cond-mat.mtrl-sci
keywords electronptychographymultislicetwistedbilayerWSe23Datomiccoordinatesmoirécorrugationinterlayerspacingvacancymappingcoordinaterefinement
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

Twisted bilayer transition-metal dichalcogenides develop out-of-plane deformations that set their electronic properties, but those deformations have been nearly impossible to measure directly. The paper reports a workflow that recovers all six atomic planes of twisted bilayer WSe2 from a single 30-second tilted 4D-STEM acquisition, using multislice electron ptychography followed by a refinement that nudges noisy depth coordinates toward physically plausible positions. In simulated benchmarks the refined coordinates match ground truth with 4.5 pm in-plane error and 5.3 pm out-of-plane error, so the authors claim picometer-scale accuracy in all three dimensions. On experimental data the model exposes individual selenium vacancies, all confined to the outer Se planes, along with sub-angstrom interlayer spacing variations between AA and AB stacking regions and a mix of breathing- and bending-type moiré corrugations that theory had not predicted in close proximity. The payoff of the claim is that atom-by-atom 3D models of buried 2D interfaces become routine from fast, single-orientation data.

What carries the argument

The load-bearing machinery is multislice electron ptychography (MEP), which reconstructs the 3D complex object potential as a stack of slices from 4D-STEM diffraction data. What carries the 3D coordinate claim is the combination of a 15-degree sample tilt, so atoms that share a lateral column are displaced in x,y and can be located with the high lateral precision, and the coordinate-refinement loss of Eq. S1, whose terms keep the x,y positions from ptychography, enforce a fixed W-Se bond length B = 2.5379 Å, weakly hold the z of W atoms near a fixed atom, and use a ReLU penalty to keep Se atoms in the correct layer. A final selection step chooses, among 401 repeated refinements, the model whose mean interlayer spacing is closest to bulk 2H-WSe2, 6.49 Å. The machinery works by letting the precise lateral information compensate for the much poorer depth resolution of ptychography, measured here as 7.5 Å full width at half maximum.

What would settle it

Simulate 4D-STEM datasets from molecular dynamics structures whose mean interlayer spacing is deliberately varied away from 6.49 Å (for example by ±0.3 Å), run the full retrieval pipeline, and check whether the recovered mean spacing is pulled toward 6.49 Å; if the 5.3 pm z error is achieved only when the truth is the bulk value, the claim of absolute picometer z accuracy is falsified. A complementary experiment would image the same area at +15 and -15 degrees of tilt and require the un-tilted 3D coordinates to agree within the claimed precision.

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Extended reading notes

Core claim

On the authors' own terms, the discovery is that augmenting multislice electron ptychography with two simple priors, atomicity plus known W-Se bond lengths and the bulk interlayer spacing as a selector, turns a depth-limited 3D phase volume into a genuine 3D atomic model. Tilting the sample by 15 degrees separates the otherwise-overlapping Se columns in the lateral plane, so each of the six planes can be assigned; a coordinate refinement then uses the highly accurate x,y peaks as anchors and the bond-length constraint to correct z positions. The benchmark claims 4.5 pm rms in-plane error and 5.3 pm rms z error after refinement, and the experimental models show vacancies confined to outer Se layers, interlayer spacings of 6.7 to 6.9 Å in AA regions versus 6.2 to 6.4 Å in AB regions, and curvature maps in which two of three AA regions breathe outward while one bends in-phase, a mixed corrugation pattern the authors describe as a new type of structural disorder.

Load-bearing premise

The refinement assumes the twisted bilayer's internal bond lengths and mean interlayer spacing equal bulk 2H-WSe2 values, fixing the W-Se bond at 2.5379 Å and selecting the refinement whose average interlayer spacing is closest to 6.49 Å; if the sample deviates from bulk in its average geometry, the absolute z coordinates and the 5.3 pm z-accuracy benchmark are biased.

Editorial extensions

If this is right

  • All six atomic planes of a twisted bilayer can be individually resolved from one tilt direction, so layer-resolved defect counts and stacking assignments no longer require tomography.
  • Interlayer spacing maps become directly measurable in experiment, enabling direct comparison with molecular dynamics predictions for moiré reconstructions.
  • The layer assignments of vacancies settle a debate in this sample: the Se vacancies sit only in the two outer planes, pointing to beam or preparation damage rather than intrinsic growth defects.
  • Mixed breathing- and bending-type corrugations at nearby AA regions imply that out-of-plane disorder is spatially non-uniform, a feature that should enter models of moiré electronic structure.
  • Because a single dataset takes about 30 seconds to acquire, the approach opens the door to 3D in situ studies of structural transformations in 2D materials.

Reading between the lines

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

  • The paper's absolute z values inherit the bulk anchor: if the true mean interlayer spacing of the twisted bilayer deviates from 6.49 Å, the reported absolute depths and the 5.3 pm benchmark shift together, while the relative corrugation pattern and layer assignments would survive.
  • A natural extension is to acquire the same area at two opposite tilts and demand consistent un-tilted coordinates; agreement would remove the need for the bulk anchor and give a direct, prior-free check on absolute z.
  • The observation that bending and breathing modes coexist at neighbouring AA regions suggests that local strain history and kinetic trapping, not just equilibrium energetics, set the corrugation; in situ heating or repeated imaging could test whether the bending mode anneals away.
  • The same pipeline should transfer to other 2D stacks whose bond lengths and layer spacings are known, but for heterobilayers with unknown interlayer distance the anchor would need to be replaced by an independent calibration.
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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 manuscript reports a workflow for retrieving 3D atomic coordinates of twisted bilayer WSe2 from a single tilted multislice electron ptychography (MEP) acquisition. The authors simulate a 4D-STEM dataset (Prismatic multislice, frozen phonons, Poisson noise) from MD coordinates, reconstruct with fold_slice, extract peaks from the 3D phase, and refine coordinates by minimizing a loss function that includes lateral fidelity, a fixed W-Se bond length, vertical spacing, and vertical ordering terms. They report in-plane rms error of 4.5 pm and z rms error improving from 81 pm to 5.3 pm after refinement. In experiment, they map Se vacancies exclusively to the outer Se planes, measure interlayer spacing variations (larger in AA than AB regions), and report mixed breathing and bending corrugations at AA regions. The central claim is picometer-scale 3D accuracy from a single orientation in about 30 seconds of acquisition.

Significance. If the accuracy claim were established, the work would be an important advance: single-orientation MEP with priors could provide routine 3D atomic models of 2D heterointerfaces, including buried layers, defects, and sub-angstrom out-of-plane deformations. The simulation benchmark is well constructed (Prismatic multislice, frozen phonons, Poisson noise) and the refinement loss is explicit and reproducible. The layer-resolved vacancy assignment and the relative AA/AB interlayer contrast are likely robust. However, the quantitative z-accuracy benchmark is not independent of the priors: the fixed bond length and the post-hoc selection of the mean interlayer spacing to bulk values determine much of the reported 5.3 pm, so the headline claim overstates what is actually measured. The experimental absolute interlayer spacings should be interpreted as conditional on the bulk anchoring.

major comments (3)
  1. [Supplementary Text, 'Coordinate refinement'; Eq. S1; Fig. 2D; fig. S10] The reported z rms error of 5.3 pm does not independently validate depth retrieval. The refinement enforces every W-Se bond to exactly B = 2.5379 Å with weight 51.0 Å^-2, and among 401 repeated refinements the model whose mean interlayer z spacing is closest to the bulk 2H-WSe2 value of 6.49 Å is selected. Given the in-plane error of 4.5 pm, the bond-length constraint fixes each Se z position relative to its W atom to within a few pm through the geometry of the bond, and the selection removes the dominant systematic error in the interlayer distance, which has a 10th-90th percentile spread of -0.16 to +0.77 Å across refinements (fig. S10A). The MD ground truth is generated from potentials fitted to the same bulk lattice parameters, so the benchmark largely rewards consistency with the priors. The authors should report the z error without the interlayer-spacing selection and quantify how much of the 5.3 pm is attributable to the priors rather than to the ptychographic z information.
  2. [Supplementary Text, 'Rescaling x,y coordinates'; Fig. 2D] The 4.5 pm in-plane rms error is measured after multiplying all x,y coordinates by a global factor 0.991, chosen to align the retrieved coordinates with ground truth. This post-hoc scaling is a fit parameter in the benchmark; without it the raw in-plane error is not reported. The manuscript should report the unscaled in-plane error and justify the rescaling as a calibration procedure rather than an accuracy-enhancing adjustment, or remove the scaling from the headline accuracy claim.
  3. [Results, Fig. 4B,D and Supplementary Text 'Coordinate refinement'] The experimental interlayer spacings of 6.7-6.9 Å in AA regions are produced by a refinement selected to have a mean interlayer spacing equal to the bulk value of 6.49 Å. The absolute values are therefore conditional on the priors being exactly correct; the comparison with MD simulations, which are fitted to the same bulk parameters, is partly by construction. The relative AA-to-AB contrast and the soliton behavior are more robust, and the authors should frame those as the validated experimental results, while presenting the absolute spacings as prior-anchored.
minor comments (4)
  1. [Abstract and Discussion] The abstract states that the workflow 'solve[s] the 3D atomic coordinates ... with picometer-scale accuracy', but the accuracy is measured only on simulated data; the experimental coordinates have no ground truth. Suggest rewording to indicate that simulations indicate picometer-scale accuracy.
  2. [Fig. 2D and Supplementary Text] The histograms in Fig. 2D lack axis labels for the error distributions, and the main text does not mention that the mean interlayer spacing anchor is applied; a brief main-text note would help readers interpret the 5.3 pm value correctly.
  3. [Supplementary Text, 'Rescaling x,y coordinates'] The sentence explaining the 0.991 rescaling should state explicitly that this correction is applied only to the simulation benchmark and not to the experimental coordinates in Fig. 4A.
  4. [Materials and Methods, Coordinate retrieval] The manual steps in coordinate retrieval (labeling Good/Poor/Vacancy, manually adding vacancy sites, and manually shifting misplaced Se atoms) are described in the supplementary but not summarized in the main text; a short paragraph would clarify the degree of human intervention in the reported models.

Circularity Check

2 steps flagged · score 6.0 of 10

The 5.3 pm z-accuracy benchmark and the mean interlayer spacing are enforced by the priors (fixed W-Se bond length plus selection to bulk 6.49 Å), so the headline 3D accuracy claim largely reduces to the 4.5 pm in-plane error propagated through the imposed bond length, not to independent depth retrieval.

  1. fitted input called prediction [Supplementary Text, 'Coordinate refinement' (Eq. S1); main text Fig. 2D]
    "WB = (0.14 Å)^−2 = 51.0 Å^−2 ... B = 2.5379 Å ... 'we ran the coordinate refinement multiple times and used the sets of refined coordinates that produced the average interlayer spacing closest to the value from the crystal structure of bulk 2H-WSe2 (6.49 Å)' ... 'After refinement, the in-plane rms error is 4.5 pm and the z rms error is 5.3 pm.'"

    The z-error benchmark is not an independent measure of depth retrieval. Eq. S1 enforces every W-Se bond to exactly B = 2.5379 Å with a stiff weight, so once the x,y coordinates are fixed to 4.5 pm accuracy, the W-Se vertical separation is algebraically forced to sqrt(B^2 - r_xy^2); this propagates the 4.5 pm in-plane error into roughly 5 pm of z error. The remaining interlayer-spacing degree of freedom is not fitted to the data but selected post hoc among 401 refinements to match bulk 2H-WSe2 (6.49 Å), and the MD ground truth is relaxed with potentials parameterized to the same bulk values. The reported 5.3 pm rms z error is therefore consistency with the priors, whereas the raw ptychographic z error was 81 pm.

  2. fitted input called prediction [Supplementary Text, 'Coordinate refinement'; main text 'Mapping out-of-plane structural reconstruction in twisted bilayer WSe2' (Fig. 4D)]
    "Due to the limited accuracy in retrieving the mean interlayer z spacing through ptychography alone, for the atomic models in Fig. 2 and Fig. 4A, we ran the coordinate refinement multiple times and used the sets of refined coordinates that produced the average interlayer spacing closest to the value from the crystal structure of bulk 2H-WSe2 (6.49 Å) (66)."

    Because the mean interlayer spacing is anchored to the bulk 2H-WSe2 value before the model is reported, the experimental absolute AA spacings (6.7-6.9 Å) and the claimed 'excellent quantitative agreement' with MD are conditional on the assumption that the twisted bilayer's mean spacing equals the bulk value. Any uniform deviation of the true mean interlayer spacing is removed by construction; only the relative AA-versus-AB variation remains data-driven. Thus the mean interlayer spacing is an input selected to match bulk, not an independently predicted quantity.

full rationale

The paper's relative results—layer-by-layer vacancy assignment, the AA/AB/soliton interlayer-spacing contrast, and the mixed bending/breathing curvature modes—have substantial independent content and are not manufactured by the priors. However, the headline quantitative claim of 'picometer-scale accuracy' in all three dimensions is substantially produced by the priors rather than by the ptychographic z information. The fixed W-Se bond length converts the demonstrated 4.5 pm in-plane accuracy into about 5 pm of z accuracy by simple geometry, and the mean interlayer spacing is selected to equal the bulk value, while the simulated ground truth was generated with force fields fitted to the same bulk parameters. This makes the 5.3 pm z rms error a largely self-consistent benchmark rather than an external validation of single-orientation 3D retrieval. The paper's self-citations (e.g., Refs. 25 and 26) are methodological rather than load-bearing for the circularity. The corrugation and vacancy findings, being relative or layer-assignment claims, are not circular. Overall, partial circularity in the central accuracy claim warrants a score of 6.

Assumptions & free parameters 4 free parameters · 5 assumptions · 0 invented entities

The central quantitative claims rest on priors imported from bulk WSe2 (bond length, interlayer spacing) and on simulation as ground truth; these are stated in the SI but limit the independence of the measurements.

free parameters (4)
  • W-Se bond length constraint B = 2.5379 Å
    Taken from bulk 2H-WSe2 and imposed as a harmonic prior in the refinement loss (Eq. S1, bond length loss). If the twisted bilayer bond lengths deviate from bulk, the refined z coordinates are biased.
  • Average interlayer spacing anchor = 6.49 Å
    Bulk 2H-WSe2 spacing used to select among repeated refinements; anchors the absolute interlayer spacing map and contributes to the 5.3 pm z accuracy benchmark.
  • x,y rescaling factor = 0.991
    Applied to simulated ptychography coordinates before comparing to ground truth; fitted to the benchmark data to correct for probe position correction miscalibration.
  • Refinement loss weights = WLD=120 Å^-2, WB=51.0 Å^-2, WVS=0.14 Å^-2, WVO=50 Å^-1, d1=2.0 Å, d2=4.5 Å
    Hand-chosen weights in Eq. S1 that set the balance between data fidelity and priors; they influence the final coordinates and are not derived from data.
assumptions (5)
  • domain assumption Peaks in the 3D phase of the multislice ptychographic reconstruction correspond to atomic positions
    Stated in 'Coordinate retrieval': 'Generally, the peaks in the phase of the 3D object function produced by multislice ptychography correspond to atoms.' This underlies peak finding; overlapping atoms and edge artifacts require manual handling.
  • domain assumption The sample is composed of discrete atoms with known mean W-Se bond length and bulk-like average interlayer spacing
    Invoked in the introduction ('atomicity') and in the refinement loss function (Eq. S1) with B=2.5379 Å; also the bulk 6.49 Å spacing is used to select refinements. These priors are load-bearing for the z coordinate claims.
  • domain assumption Classical MD with Stillinger-Weber and Kolmogorov-Crespi potentials gives the correct relaxed ground truth for twisted bilayer WSe2
    MD coordinates serve as ground truth for the simulation benchmark (Fig. 2, fig. S12) and as the comparison for experimental interlayer spacing and curvature (Fig. 4E-G). Force-field accuracy is assumed.
  • domain assumption The multislice forward model and maximum-likelihood ptychographic reconstruction accurately recover the 3D object
    Used throughout (fold slice, Prismatic); depth resolution and phase fidelity depend on the accuracy of these models and the chosen parameters (probe modes, slices, regularization gamma=0.1).
  • domain assumption Tricubic interpolation of the phase and the FWHM-based depth resolution assignment correctly localize atoms in z
    Used in coordinate retrieval and in the 7.5 Å depth resolution estimate (fig. S5); assumes the phase near an atom is a smooth single-maximum function of z.

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Cite this review

Pith. "Pith review of 3D Mapping of Defects and Moir\'e Corrugations via Electron Ptychography Atomic Coordinate Retrieval." pith.science (2026). https://pith.science/paper/TTSFDNBK

@misc{pith2026250907140,
  author       = {Pith},
  title        = {Pith review of: 3D Mapping of Defects and Moir\'e Corrugations via Electron Ptychography Atomic Coordinate Retrieval},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/TTSFDNBK}},
  note         = {Machine review of arXiv:2509.07140}
}
abstract

Defects and reconstructions in 2D moir\'e materials cause out-of-plane deformations which strongly modify their electronic properties but are difficult to experimentally access. Here, we solve the 3D atomic coordinates of twisted bilayer WSe$_2$ with picometer-scale accuracy using multislice electron ptychography (MEP) acquired from a single orientation. The resulting atomic models individually visualize each of the six atomic planes, revealing the curvature of each WSe$_2$ layer, variations in the interlayer spacing, and the 3D locations of individual vacancies -- which lie exclusively in the outer Se planes. We also observe a new, unexpected type of structural disorder consisting of mixed bending -- and breathing-type moir\'e-induced corrugations that should strongly impact the emergent electronic properties. Broadly, our methods generate 3D atom-by-atom models of a 2D heterointerface from data acquired in about 30 seconds, methods that should unlock routine access to 3D atomic information in 2D systems and catalyze design methods to control out-of-plane deformations.

Figures

Figures reproduced from arXiv: 2509.07140 by the authors.

Figure 3
Figure 3. Diffraction patterns padded to 192 [PITH_FULL_IMAGE:figures/full_fig_p012_3.png] view at source ↗

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Works this paper leans on

66 extracted references · 28 canonical work pages

  1. [2]

    Yoo, et al

    H. Yoo, et al. , Atomic and electronic reconstruction at the van der Waals interface in twisted bilayer graphene. Nature Materials 18 (5), 448–453 (2019), doi:10.1038/ s41563-019-0346-z, https://doi.org/10.1038/s41563-019-0346-z

  2. [3]

    Weston, et al., Atomic reconstruction in twisted bilayers of transition metal dichalco- genides

    A. Weston, et al., Atomic reconstruction in twisted bilayers of transition metal dichalco- genides. Nature Nanotechnology 15 (7), 592–597 (2020), doi:10.1038/s41565-020-0682-9, https://doi.org/10.1038/s41565-020-0682-9

  3. [4]

    N. P. Kazmierczak, et al. , Strain fields in twisted bilayer graphene. Nature Materials 20 (7), 956–963 (2021), doi:10.1038/s41563-021-00973-w, https://doi.org/10.1038/ s41563-021-00973-w

  4. [5]

    Edelberg, H

    D. Edelberg, H. Kumar, V. Shenoy, H. Ochoa, A. N. Pasupathy, Tunable strain soliton networks confine electrons in van der Waals materials. Nature Physics 16 (11), 1097–1102 (2020), doi:10.1038/s41567-020-0953-2, https://doi.org/10.1038/ s41567-020-0953-2

  5. [6]

    Butz, et al

    B. Butz, et al. , Dislocations in bilayer graphene. Nature 505 (7484), 533–537 (2014), doi:10.1038/nature12780, https://doi.org/10.1038/nature12780

  6. [7]

    M. H. Naik, M. Jain, Ultraflatbands and Shear Solitons in Moir´ e Patterns of Twisted Bilayer Transition Metal Dichalcogenides. Phys. Rev. Lett. 121, 266401 (2018), doi:10.1103/PhysRevLett.121.266401, https://link.aps.org/doi/10.1103/ PhysRevLett.121.266401

  7. [8]

    K. P. Nuckolls, A. Yazdani, A microscopic perspective on moir´ e materials. Nature Re- views Materials 9 (7), 460–480 (2024), doi:10.1038/s41578-024-00682-1, https://doi. org/10.1038/s41578-024-00682-1

  8. [9]

    Cao, et al

    Y. Cao, et al. , Unconventional superconductivity in magic-angle graphene superlat- tices. Nature 556 (7699), 43–50 (2018), doi:10.1038/nature26160, https://doi.org/ 10.1038/nature26160

Show all 66 references
  1. [10]

    Guo, et al

    Y. Guo, et al. , Superconductivity in 5.0 ° twisted bilayer WSe 2. Nature 637 (8047), 839–845 (2025), doi:10.1038/s41586-024-08381-1, https://doi.org/10.1038/ s41586-024-08381-1. 15

  2. [11]

    Xia, et al

    Y. Xia, et al. , Superconductivity in twisted bilayer WSe 2. Nature 637 (8047), 833–838 (2025), doi:10.1038/s41586-024-08116-2, https://doi.org/10.1038/ s41586-024-08116-2

  3. [12]

    Tillotson, et al

    E. Tillotson, et al. , Scanning Electron Microscopy Imaging of Twist Domains in Tran- sition Metal Dichalcogenide Heterostructures. ACS Nano 18 (50), 34023–34033 (2024), pMID: 39642004, doi:10.1021/acsnano.4c09364, https://doi.org/10.1021/acsnano. 4c09364

  4. [13]

    Ochoa, R

    H. Ochoa, R. M. Fernandes, Degradation of Phonons in Disordered Moir´ e Superlattices. Phys. Rev. Lett. 128, 065901 (2022), doi:10.1103/PhysRevLett.128.065901, https:// link.aps.org/doi/10.1103/PhysRevLett.128.065901

  5. [14]

    Maity, M

    I. Maity, M. H. Naik, P. K. Maiti, H. R. Krishnamurthy, M. Jain, Phonons in twisted transition-metal dichalcogenide bilayers: Ultrasoft phasons and a transition from a superlubric to a pinned phase. Phys. Rev. Res. 2, 013335 (2020), doi:10.1103/ PhysRevResearch.2.013335, https...

  6. [15]

    Zhang, et al

    X.-W. Zhang, et al. , Polarization-driven band topology evolution in twisted MoTe 2 and WSe2. Nature Communications 15 (1), 4223 (2024), doi:10.1038/s41467-024-48511-x, https://doi.org/10.1038/s41467-024-48511-x

  7. [16]

    Maity, P

    I. Maity, P. K. Maiti, H. R. Krishnamurthy, M. Jain, Reconstruction of moir´ e lattices in twisted transition metal dichalcogenide bilayers. Phys. Rev. B 103, L121102 (2021), doi:10.1103/PhysRevB.103.L121102, https://link.aps.org/doi/10.1103/PhysRevB. 103.L121102

  8. [17]

    Zhang, W

    B. Zhang, W. Qiu, X. Liao, L. He, Y. Ni, Impact of out-of-plane deformation on atomic reconstruction in twisted van der Waals bilayers. Journal of the Mechanics and Physics of Solids 189, 105693 (2024), doi:https://doi.org/10.1016/j.jmps.2024.105693, https: //www.sciencedirect...

  9. [18]

    Brihuega, et al

    I. Brihuega, et al. , Unraveling the Intrinsic and Robust Nature of van Hove Singular- ities in Twisted Bilayer Graphene by Scanning Tunneling Microscopy and Theoretical Analysis. Phys. Rev. Lett. 109, 196802 (2012), doi:10.1103/PhysRevLett.109.196802, https://link.aps.org/doi...

  10. [19]

    Molino, et al., Influence of Atomic Relaxations on the Moir´ e Flat Band Wave Functions in Antiparallel Twisted Bilayer WS 2

    L. Molino, et al., Influence of Atomic Relaxations on the Moir´ e Flat Band Wave Functions in Antiparallel Twisted Bilayer WS 2. Nano Letters 23 (24), 11778–11784 (2023), doi: 10.1021/acs.nanolett.3c03735, https://doi.org/10.1021/acs.nanolett.3c03735. 16

  11. [20]

    J. Miao, P. Ercius, S. J. L. Billinge, Atomic electron tomography: 3D structures without crystals. Science 353 (6306), aaf2157 (2016), doi:10.1126/science.aaf2157, https://www. science.org/doi/abs/10.1126/science.aaf2157

  12. [21]

    M. C. Scott, et al., Electron tomography at 2.4-˚ angstr¨ om resolution.Nature 483 (7390), 444–447 (2012), doi:10.1038/nature10934, https://doi.org/10.1038/nature10934

  13. [22]

    Tian, et al

    X. Tian, et al. , Correlating the three-dimensional atomic defects and electronic properties of two-dimensional transition metal dichalcogenides. Nature Materials 19 (8), 867–873 (2020), doi:10.1038/s41563-020-0636-5, https://doi.org/10.1038/ s41563-020-0636-5

  14. [23]

    Tian, et al

    X. Tian, et al. , Capturing 3D atomic defects and phonon localization at the 2D het- erostructure interface. Science Advances 7 (38), eabi6699 (2021), doi:10.1126/sciadv. abi6699, https://www.science.org/doi/abs/10.1126/sciadv.abi6699

  15. [24]

    Ercius, O

    P. Ercius, O. Alaidi, M. J. Rames, G. Ren, Electron Tomography: A Three-Dimensional Analytic Tool for Hard and Soft Materials Research. Advanced Materials 27 (38), 5638–5663 (2015), doi:https://doi.org/10.1002/adma.201501015, https://advanced. onlinelibrary.wiley.com/doi/abs/1...

  16. [25]

    Chen, et al

    Z. Chen, et al. , Electron ptychography achieves atomic-resolution limits set by lattice vibrations. Science 372 (6544), 826–831 (2021), doi:10.1126/science.abg2533, https: //www.science.org/doi/abs/10.1126/science.abg2533

  17. [26]

    Zhang, et al

    Y. Zhang, et al. , Atom-by-atom imaging of moir´ e phasons with electron ptychogra- phy. Science 389 (6758), 423–428 (2025), doi:10.1126/science.adw7751, https://www. science.org/doi/abs/10.1126/science.adw7751

  18. [27]

    C. M. O’Leary, et al. , Three-dimensional structure of buried heterointerfaces re- vealed by multislice ptychography. Phys. Rev. Appl. 22, 014016 (2024), doi:10.1103/ PhysRevApplied.22.014016, https://link.aps.org/doi/10.1103/PhysRevApplied. 22.014016

  19. [28]

    S. M. Ribet, et al., Uncovering the three-dimensional structure of upconverting core–shell nanoparticles with multislice electron ptychography. Applied Physics Letters 124 (24), 240601 (2024), doi:10.1063/5.0206814, https://doi.org/10.1063/5.0206814

  20. [29]

    Zhu, et al

    M. Zhu, et al. , Insights into Chemical and Structural Order at Planar Defects in Pb2MgWO6 Using Multislice Electron Ptychography. ACS Nano 19 (5), 5568–5576 (2025), pMID: 39871489, doi:10.1021/acsnano.4c14833, https://doi.org/10.1021/ acsnano.4c14833. 17

  21. [30]

    E. H. R. Tsai, I. Usov, A. Diaz, A. Menzel, M. Guizar-Sicairos, X-ray ptychography with extended depth of field. Opt. Express 24 (25), 29089–29108 (2016), doi:10.1364/OE.24. 029089, https://opg.optica.org/oe/abstract.cfm?URI=oe-24-25-29089

  22. [31]

    K. X. Nguyen, et al. , Achieving sub-0.5-angstrom–resolution ptychography in an un- corrected electron microscope. Science 383 (6685), 865–870 (2024), doi:10.1126/science. adl2029, https://www.science.org/doi/abs/10.1126/science.adl2029

  23. [32]

    Jiang, et al., Electron ptychography of 2D materials to deep sub-˚ angstr¨ om resolution

    Y. Jiang, et al., Electron ptychography of 2D materials to deep sub-˚ angstr¨ om resolution. Nature 559 (7714), 343–349 (2018), doi:10.1038/s41586-018-0298-5, https://doi.org/ 10.1038/s41586-018-0298-5

  24. [33]

    Chen, et al., Imaging interstitial atoms with multislice electron ptychography (2024), https://arxiv.org/abs/2407.18063

    Z. Chen, et al., Imaging interstitial atoms with multislice electron ptychography (2024), https://arxiv.org/abs/2407.18063

  25. [34]

    H. L. Xin, D. A. Muller, Three-Dimensional Imaging in Aberration-Corrected Elec- tron Microscopes. Microscopy and Microanalysis 16 (4), 445–455 (2010), doi:10.1017/ S1431927610093360, https://doi.org/10.1017/S1431927610093360

  26. [35]

    Van Dyck, J

    D. Van Dyck, J. R. Jinschek, F.-R. Chen, ‘Big Bang’ tomography as a new route to atomic-resolution electron tomography. Nature 486 (7402), 243–246 (2012), doi:10.1038/ nature11074, https://doi.org/10.1038/nature11074

  27. [36]

    Rhodes, S

    D. Rhodes, S. H. Chae, R. Ribeiro-Palau, J. Hone, Disorder in van der Waals het- erostructures of 2D materials. Nature Materials 18 (6), 541–549 (2019), doi:10.1038/ s41563-019-0366-8, https://doi.org/10.1038/s41563-019-0366-8

  28. [37]

    S. M. Hus, et al. , Observation of single-defect memristor in an MoS 2 atomic sheet. Nature Nanotechnology 16 (1), 58–62 (2021), doi:10.1038/s41565-020-00789-w, https: //doi.org/10.1038/s41565-020-00789-w

  29. [38]

    Lee, et al

    C.-H. Lee, et al. , Deep Learning Enabled Strain Mapping of Single-Atom Defects in Two-Dimensional Transition Metal Dichalcogenides with Sub-Picometer Precision.Nano Letters 20 (5), 3369–3377 (2020), pMID: 32243178, doi:10.1021/acs.nanolett.0c00269, https://doi.org/10.1021/acs...

  30. [39]

    S. Ding, F. Lin, C. Jin, Quantify point defects in monolayer tungsten diselenide. Nan- otechnology 32 (25), 255701 (2021), doi:10.1088/1361-6528/abeeb2, https://dx.doi. org/10.1088/1361-6528/abeeb2

  31. [40]

    Zhou, et al., Intrinsic Structural Defects in Monolayer Molybdenum Disulfide

    W. Zhou, et al., Intrinsic Structural Defects in Monolayer Molybdenum Disulfide. Nano Letters 13 (6), 2615–2622 (2013), pMID: 23659662, doi:10.1021/nl4007479, https:// doi.org/10.1021/nl4007479. 18

  32. [41]

    Edelberg, et al

    D. Edelberg, et al. , Approaching the Intrinsic Limit in Transition Metal Diselenides via Point Defect Control. Nano Letters 19 (7), 4371–4379 (2019), pMID: 31180688, doi: 10.1021/acs.nanolett.9b00985, https://doi.org/10.1021/acs.nanolett.9b00985

  33. [42]

    Bampoulis, et al

    P. Bampoulis, et al. , Defect Dominated Charge Transport and Fermi Level Pin- ning in MoS 2/Metal Contacts. ACS Applied Materials & Interfaces 9 (22), 19278– 19286 (2017), pMID: 28508628, doi:10.1021/acsami.7b02739, https://doi.org/10. 1021/acsami.7b02739

  34. [43]

    Nowakowski, H

    K. Nowakowski, H. J. W. Zandvliet, P. Bampoulis, Barrier Inhomogeneities in Atomic Contacts on WS 2. Nano Letters 19 (2), 1190–1196 (2019), doi:10.1021/acs.nanolett. 8b04636, https://doi.org/10.1021/acs.nanolett.8b04636

  35. [44]

    Quincke, M

    M. Quincke, M. Mundszinger, J. Biskupek, U. Kaiser, Defect Density and Atomic Defect Recognition in the Middle Layer of a Trilayer MoS2 Stack. Nano Letters 24 (34), 10496– 10503 (2024), pMID: 38950105, doi:10.1021/acs.nanolett.4c02391, https://doi.org/ 10.1021/acs.nanolett.4c02391

  36. [45]

    Leiter, Y

    R. Leiter, Y. Li, U. Kaiser, In-situ formation and evolution of atomic defects in monolayer WSe2 under electron irradiation. Nanotechnology 31 (49), 495704 (2020), doi:10.1088/ 1361-6528/abb335, https://dx.doi.org/10.1088/1361-6528/abb335

  37. [46]

    W. Li, T. Brumme, T. Heine, Relaxation effects in transition metal dichalcogenide bilayer heterostructures. npj 2D Materials and Applications 8 (1), 43 (2024), doi: 10.1038/s41699-024-00477-6, https://doi.org/10.1038/s41699-024-00477-6

  38. [47]

    M. H. Naik, I. Maity, P. K. Maiti, M. Jain, Kolmogorov–Crespi Potential For Multi- layer Transition-Metal Dichalcogenides: Capturing Structural Transformations in Moir´ e Superlattices. The Journal of Physical Chemistry C 123 (15), 9770–9778 (2019), doi: 10.1021/acs.jpcc.8b103...

  39. [48]

    Rakib, P

    T. Rakib, P. Pochet, E. Ertekin, H. T. Johnson, Corrugation-driven symmetry breaking in magic-angle twisted bilayer graphene. Communications Physics 5 (1), 242 (2022), doi:10.1038/s42005-022-01013-y, https://doi.org/10.1038/s42005-022-01013-y

  40. [49]

    J. Wang, E. Tosatti, Universal moir´ e buckling of freestanding 2D bilayers. Proceedings of the National Academy of Sciences 121 (49), e2418390121 (2024), doi:10.1073/pnas. 2418390121, https://www.pnas.org/doi/abs/10.1073/pnas.2418390121

  41. [50]

    F. M. Arnold, A. Ghasemifard, A. Kuc, J. Kunstmann, T. Heine, Relaxation effects in twisted bilayer molybdenum disulfide: structure, stability, and electronic properties. 2D 19 Materials 10 (4), 045010 (2023), doi:10.1088/2053-1583/aceb75, https://dx.doi.org/ 10.1088/2053-1583/aceb75

  42. [51]

    Y. Huang, et al., Universal mechanical exfoliation of large-area 2D crystals.Nature Com- munications 11 (1), 2453 (2020), doi:10.1038/s41467-020-16266-w, https://doi.org/ 10.1038/s41467-020-16266-w

  43. [52]

    Heyl, et al

    M. Heyl, et al. , Thermally Activated Gold-Mediated Transition Metal Dichalcogenide Exfoliation and a Unique Gold-Mediated Transfer. Physica Status Solidi (RRL) – Rapid Research Letters 14 (11), 2000408 (2020), doi:https://doi.org/10.1002/pssr.202000408, https://onlinelibrary....

  44. [53]

    M. W. Tate, et al., High Dynamic Range Pixel Array Detector for Scanning Transmission Electron Microscopy. Microscopy and Microanalysis 22 (1), 237–249 (2016), doi:10.1017/ S1431927615015664

  45. [54]

    Jiang, fold slice: Electron/X-ray ptychography and tomography/laminography, https://github.com/yijiang1/fold_slice, accessed: 2023-07-26

    Y. Jiang, fold slice: Electron/X-ray ptychography and tomography/laminography, https://github.com/yijiang1/fold_slice, accessed: 2023-07-26

  46. [55]

    Wakonig, et al

    K. Wakonig, et al. , PtychoShelves, a versatile high-level framework for high- performance analysis of ptychographic data. Journal of Applied Crystallography 53 (2), 574–586 (2020), doi:10.1107/S1600576720001776, https://doi.org/10.1107/ S1600576720001776

  47. [56]

    Thibault, M

    P. Thibault, M. Guizar-Sicairos, Maximum-likelihood refinement for coherent diffractive imaging. New Journal of Physics 14 (2012), doi:10.1088/1367-2630/14/6/063004

  48. [57]

    Thibault, A

    P. Thibault, A. Menzel, Reconstructing state mixtures from diffraction measurements. Nature 494 (7435), 68–71 (2013), doi:10.1038/nature11806, https://doi.org/10. 1038/nature11806

  49. [58]

    Q.-Y. Zhou, J. Park, V. Koltun, Open3D: A Modern Library for 3D Data Processing (2018), https://arxiv.org/abs/1801.09847

  50. [59]

    Rusinkiewicz, Estimating curvatures and their derivatives on triangle meshes, in Pro- ceedings

    S. Rusinkiewicz, Estimating curvatures and their derivatives on triangle meshes, in Pro- ceedings. 2nd International Symposium on 3D Data Processing, Visualization and Trans- mission, 2004. 3DPVT 2004. , Y. Aloimonos, G. Taubin, Eds. (IEEE) (2004), pp. 486– 493, doi:10.1109/TD...

  51. [60]

    A. P. Thompson, et al. , LAMMPS - a flexible simulation tool for particle-based ma- terials modeling at the atomic, meso, and continuum scales. Computer Physics Com- munications 271, 108171 (2022), doi:https://doi.org/10.1016/j.cpc.2021.108171, https: //www.sciencedirect.com/s...

  52. [61]

    S. C. Harvey, R. K.-Z. Tan, T. E. Cheatham III, The flying ice cube: Velocity rescaling in molecular dynamics leads to violation of energy equipartition. Journal of Computational Chemistry 19 (7), 726–740 (1998), https://doi.org/10.1002/(SICI) 1096-987X(199805)19:7<726::AID-JC...

  53. [62]

    Kim, et al

    K. Kim, et al. , van der Waals Heterostructures with High Accuracy Rotational Align- ment. Nano Letters 16 (3), 1989–1995 (2016), doi:10.1021/acs.nanolett.5b05263, https: //doi.org/10.1021/acs.nanolett.5b05263

  54. [63]

    Lekien, J

    F. Lekien, J. Marsden, Tricubic interpolation in three dimensions. International Journal for Numerical Methods in Engineering 63 (3), 455–471 (2005), doi:https://doi.org/10. 1002/nme.1296, https://onlinelibrary.wiley.com/doi/abs/10.1002/nme.1296

  55. [64]

    Walker, U

    P. Walker, U. Krohn, D. Carty, ARBTools: A Tricubic Spline Interpolator for Three- Dimensional Scalar or Vector Fields. Journal of Open Research Software (2019), doi: 10.5334/jors.258

  56. [65]

    D. P. Kingma, J. Ba, Adam: A Method for Stochastic Optimization, in 3rd International Conference on Learning Representations, ICLR 2015, San Diego, CA, USA, May 7-9, 2015, Conference Track Proceedings, Y. Bengio, Y. LeCun, Eds. (2015), http://arxiv. org/abs/1412.6980

  57. [66]

    B. F. Mentzen, M. J. Sienko, Preparation and X-Ray Study of Mixed-Anion Tung- sten Dichalcogenides. Inorganic Chemistry 15 (9), 2198–2202 (1976), doi:10.1021/ ic50163a040, https://doi.org/10.1021/ic50163a040

  58. [67]

    opposite

    L. Rangel DaCosta, et al. , Prismatic 2.0 – Simulation software for scanning and high resolution transmission electron microscopy (STEM and HRTEM). Micron 151, 103141 (2021), doi:10.1016/j.micron.2021.103141, https://www.sciencedirect.com/ science/article/pii/S0968432821001323...

Pith tools

Reviewed August 15, 2026 · model on record in the stance chip above.