Ultramicroscopy最新文献

Corrigendum to "Structure-preserving Gaussian denoising of FIB-SEM volumes" [Ultramicroscopy Volume 246, 113674]. 对 "FIB-SEM 体积的结构保留高斯去噪 "的更正 [Ultramicroscopy Volume 246, 113674]。

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-12-01 Epub Date: 2024-10-26 DOI: 10.1016/j.ultramic.2024.114065

V González-Ruiz, M R Fernández-Fernández, J J Fernández

引用次数: 0

Toward quantitative thermoelectric characterization of (nano)materials by in-situ transmission electron microscopy 利用原位透射电子显微镜对（纳米）材料进行定量热电表征。

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-11-06 DOI: 10.1016/j.ultramic.2024.114071

Simon Hettler , Mohammad Furqan , Andrés Sotelo , Raul Arenal

We explore the possibility to perform an in-situ transmission electron microscopy (TEM) thermoelectric characterization of materials. A differential heating element on a custom in-situ TEM microchip allows to generate a temperature gradient across the studied materials, which are simultaneously measured electrically. A thermovoltage was induced in all studied devices, whose sign corresponds to the sign of the Seebeck coefficient of the tested materials. The results indicate that in-situ thermoelectric TEM studies can help to profoundly understand fundamental aspects of thermoelectricity, which is exemplary demonstrated by tracking the thermovoltage during in-situ crystallization of an amorphous Ge thin film. We propose an improved in-situ TEM microchip design, which should facilitate a full quantitative measurement of the induced temperature gradient, the electrical and thermal conductivities, as well as the Seebeck coefficient. The benefit of the in-situ approach is the possibility to directly correlate the thermoelectric properties with the structure and chemical composition of the entire studied device down to the atomic level, including grain boundaries, dopants or crystal defects, and to trace its dynamic evolution upon heating or during the application of electrical currents.

我们探索了对材料进行原位透射电子显微镜（TEM）热电特性分析的可能性。在定制的原位 TEM 微芯片上安装一个差分加热元件，可以在所研究的材料上产生温度梯度，并同时进行电学测量。在所有研究装置中都会产生热电压，其符号与被测材料塞贝克系数的符号相对应。结果表明，原位热电 TEM 研究有助于深刻理解热电的基本方面，非晶态 Ge 薄膜原位结晶过程中的热电压跟踪就是一个很好的例子。我们提出了一种改进的原位 TEM 微芯片设计，它有助于对诱导温度梯度、电导率和热导率以及塞贝克系数进行全面的定量测量。原位方法的优势在于可以直接将热电性能与整个被研究器件的结构和化学成分（包括晶界、掺杂物或晶体缺陷）关联到原子水平，并跟踪其在加热或施加电流时的动态演变。

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引用次数: 0

New experimental methodology for determining the second crossover energy in insulators under stationary e-irradiation in a SEM 在扫描电子显微镜中确定静态电子辐照下绝缘体第二交叉能的新实验方法。

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-11-01 DOI: 10.1016/j.ultramic.2024.114069

H. Hammami, S. Fakhfakh

A new experimental methodology is proposed which uses the electrostatic influence method (EIM) in scanning electron microscope (SEM) in order to estimate the second crossover energy E_C2 for uncharged insulators. This experimental methodology based on simultaneous time measurement of the displacement and leakage currents, is approached to the short pulse irradiation technique but under stationary e-irradiation and allows determining the intrinsic secondary electron emission yield, σ₀ (σ₀ is the value of the total secondary electron yield just at the beginning of the irradiation before significant charge accumulation or before the formation of a surface potential). The obtained value of E_C2 for soda-lime glass is confirmed by two additional experiments based on secondary electron imaging. This value is in good agreement with those previously obtained by other studies based on the surface potential measurement or the pulsed irradiation technique.

本文提出了一种新的实验方法，利用扫描电子显微镜（SEM）中的静电影响法（EIM）来估算不带电绝缘体的二次交叉能 EC2。这种实验方法基于对位移电流和泄漏电流的同步时间测量，接近于短脉冲辐照技术，但需要在静态电子辐照条件下进行，可以确定固有的二次电子发射率σ0（σ0 是辐照刚开始时在电荷大量积累或表面电势形成之前的总二次电子发射率值）。钠钙玻璃的 EC2 值通过另外两次基于二次电子成像的实验得到了证实。该值与之前其他基于表面电位测量或脉冲辐照技术的研究得出的值十分吻合。

引用次数: 0

Beyond the random phase approximation (RPA): First principles calculation of the valence EELS spectrum for KBr including local field, quasiparticle, excitonic and spin orbit coupling effects 超越随机相近似 (RPA)：KBr 价电子能谱的第一性原理计算，包括局部场、准粒子、激子和自旋轨道耦合效应。

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-30 DOI: 10.1016/j.ultramic.2024.114070

V.J. Keast

The low energy region (< 50 eV) of the electron energy loss spectrum (EELS) can contain a great deal of spectral detail associated with excitations of the valence electrons. Calculation of the spectra from first principles can assist with interpretation and the most widely used method is the random phase approximation (RPA), usually neglecting local field effects (LFE). For KBr this approach is insufficient due to the importance of quasiparticle and excitonic effects. Calculations including these multi-electron effects are shown to give much improved agreement with the experimental spectra, and the inclusion of spin-orbit coupling (SOC) reproduces the excitonic doublet just above band-edge onset. A review of the complex theory behind these methods is given along with practical guidance on performing these calculations.

电子能量损失谱（EELS）的低能区（< 50 eV）包含大量与价电子激发有关的光谱细节。根据第一原理计算光谱有助于对光谱进行解释，最广泛使用的方法是随机相近似法（RPA），通常忽略局部场效应（LFE）。对于 KBr 来说，由于准粒子和激子效应的重要性，这种方法是不够的。包括这些多电子效应在内的计算与实验光谱的一致性大大提高，而自旋轨道耦合（SOC）的加入则重现了带边起始点上方的激子双音。本文回顾了这些方法背后的复杂理论，并提供了进行这些计算的实用指导。

引用次数: 0

A high-performance reconstruction method for partially coherent ptychography 部分相干层析成像的高性能重建方法

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-28 DOI: 10.1016/j.ultramic.2024.114068

Wenhui Xu , Shoucong Ning , Pengju Sheng , Huixiang Lin , Angus I Kirkland , Yong Peng , Fucai Zhang

Ptychography is now integrated as a tool in mainstream microscopy allowing quantitative and high-resolution imaging capabilities over a wide field of view. However, its ultimate performance is inevitably limited by the available coherent flux when implemented using electrons or laboratory X-ray sources. We present a universal reconstruction algorithm with high tolerance to low coherence for both far-field and near-field ptychography. The approach is practical for partial temporal and spatial coherence and requires no prior knowledge of the source properties. Our initial visible-light and electron data show that the method can dramatically improve the reconstruction quality and accelerate the convergence rate of the reconstruction. The approach also integrates well into existing ptychographic engines. It can also improve mixed-state and numerical monochromatisation methods, requiring a smaller number of coherent modes or lower dimensionality of Krylov subspace while providing more stable and faster convergence. We propose that this approach could have significant impact on ptychography of weakly scattering samples.

目前，层析成像技术已成为主流显微镜技术的一种工具，可在宽视场范围内进行定量和高分辨率成像。然而，在使用电子或实验室 X 射线源时，其最终性能不可避免地受到可用相干通量的限制。我们提出了一种通用的重建算法，对远场和近场层析成像的低相干性具有很高的容忍度。这种方法适用于部分时间和空间相干性，而且不需要事先了解光源特性。我们最初的可见光和电子数据表明，该方法能显著提高重建质量，并加快重建的收敛速度。这种方法还能很好地集成到现有的分色引擎中。它还能改进混合状态和数值单色化方法，需要更少的相干模式或更低维度的克雷洛夫子空间，同时提供更稳定和更快的收敛速度。我们认为，这种方法可以对弱散射样本的层析成像产生重大影响。

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引用次数: 0

A simple circularity-based approach for nanoparticle size histograms beyond the spherical approximation 超越球面近似的基于圆度的纳米粒子尺寸直方图简单方法。

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-28 DOI: 10.1016/j.ultramic.2024.114067

Florent Tournus

Conventional Transmission Electron Microscopy (TEM) is widely used for routine characterization of the size and shape of an assembly of (nano)particles. While the most basic approach only uses the projected area of each particle to infer its size (the “circular equivalent diameter” corresponding to the so-called “spherical approximation”), other shape descriptors can be determined and used for more elaborate analyses. In this article we present a generic model of particles, considered to be made of a few individual grains, and show how the equivalent size (i.e. a particle volume information) can be reliably deduced using only two basic parameters: the projected area and the perimeter of a particle. We compare this simple model to the spherical and ellipsoidal approximations and discuss its benefits. Then, partial coalescence of grains in a particle is also considered and we show how a simple analytical approximation, based on the circularity parameter of each particle, can improve the experimental determination of a particle size histogram. The analysis of experimental observations on nanoparticles assemblies obtained by mass-selected cluster deposition is presented, to illustrate the efficiency of the proposed approach for the determination of particle size just from conventional TEM images. We show how the presence of multimers offers an excellent opportunity to validate our improved and simple procedure. In addition, since the circularity plays a central role in this approach, attention is attracted on the perimeter determination in a pixelated image.

传统的透射电子显微镜（TEM）被广泛用于对（纳米）颗粒组件的尺寸和形状进行常规表征。虽然最基本的方法只是利用每个颗粒的投影面积来推断其大小（即所谓 "球面近似 "的 "圆形等效直径"），但也可以确定其他形状描述符，并用于更精细的分析。在这篇文章中，我们提出了一个通用的颗粒模型，认为它是由一些单独的颗粒组成的，并展示了如何仅使用两个基本参数就能可靠地推导出等效尺寸（即颗粒体积信息）：颗粒的投影面积和周长。我们将这一简单模型与球形和椭圆形近似模型进行了比较，并讨论了其优点。然后，我们还考虑了颗粒中颗粒的部分凝聚，并展示了基于每个颗粒的圆度参数的简单分析近似值如何改进粒度直方图的实验测定。我们介绍了对通过质量选择簇沉积获得的纳米粒子集合体的实验观察分析，以说明所提出的方法在仅从传统 TEM 图像确定粒度方面的效率。我们展示了多聚物的存在如何为验证我们改进的简单程序提供了绝佳的机会。此外，由于圆形在这种方法中起着核心作用，因此像素化图像中的周长测定也备受关注。

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引用次数: 0

Towards atom counting from first moment STEM images: Methodology and possibilities 根据第一时刻 STEM 图像进行原子计数：方法与可能性。

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-26 DOI: 10.1016/j.ultramic.2024.114066

Yansong Hao , Annick De Backer , Scott David Findlay , Sandra Van Aert

Through a simulation-based study we develop a statistical model-based quantification method for atomic resolution first moment scanning transmission electron microscopy (STEM) images. This method uses the uniformly weighted least squares estimator to determine the unknown structure parameters of the images and to isolate contributions from individual atomic columns. In this way, a quantification of the projected potential per atomic column is achieved. Since the integrated projected potential of an atomic column scales linearly with the number of atoms it contains, it can serve as a basis for atom counting. The performance of atom counting from first moment STEM imaging is compared to that from traditional HAADF STEM in the presence of noise. Through this comparison, we demonstrate the advantage of first moment STEM images to attain more precise atom counts. Finally, we compare the integrated potential extracted from first-moment images of a wedge-shaped sample to those values from the bulk crystal. The excellent agreement found between these values proves the robustness of using bulk crystal simulations as a reference library. This enables atom counting for samples with different shapes by comparison with these library values.

通过模拟研究，我们开发出一种基于统计模型的原子分辨率第一矩扫描透射电子显微镜（STEM）图像量化方法。该方法使用均匀加权最小二乘估计器来确定图像的未知结构参数，并分离出单个原子柱的贡献。通过这种方法，可以量化每个原子柱的投影电势。由于原子柱的综合投影电势与其包含的原子数量成线性关系，因此可以作为原子计数的基础。我们将第一矩 STEM 成像的原子计数性能与传统 HAADF STEM 在存在噪声的情况下的原子计数性能进行了比较。通过比较，我们证明了第一矩 STEM 图像在实现更精确原子计数方面的优势。最后，我们将从楔形样品的第一矩图像中提取的积分电势与块状晶体的积分电势值进行了比较。这些值之间的极佳一致性证明了使用块晶模拟作为参考库的稳健性。通过与这些库值进行比较，我们可以对不同形状的样品进行原子计数。

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引用次数: 0

On the instrument-dependent appearance of ion dissociation events in atom probe tomography mass spectra 原子探针断层扫描质谱中离子解离事件的出现与仪器有关

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-25 DOI: 10.1016/j.ultramic.2024.114061

Benjamin W. Caplins , Ann N. Chiaramonti , Jacob M. Garcia , Luis Miaja-Avila , Kayla H. Yano , Daniel K. Schreiber , Joseph H. Bunton

The successful application of atom probe tomography (APT) relies on the accurate interpretation of the mass spectrum (i.e.

m / z

histogram) from a sample. Some materials yield mass spectra that are amenable to a straightforward peak assignment/ranging, however, there are many materials that produce mass spectra with features that defy simple interpretation. One such example is Ga

_{2}

O

_{3}

which yields mass spectra containing several broad and difficult to interpret features. Herein, we study the GaO

^{2 +}

\to

O

^{1 +} +

Ga

^{1 +}

dissociation and we explain how this dissociation process gives rise to broad and previously unassigned features in the mass spectrum. Trajectory simulations are performed for the dissociation reaction utilizing realistic electrostatic models and compared to experiments using commercially available straight flight and reflectron based local electrode (LE) APT instruments. It is shown that the appearance of these features is strongly dependent on the specific design of the time-of-flight (ToF) mass analyzer. We explore how various experimental parameters can affect the appearance of the dissociation process in the one-dimensional (1D) mass spectrum and in the two-dimensional (2D) correlation histogram. While the focus of this work is on a particular dissociation process related to Ga

_{2}

O

_{3}

, the understanding gained in the course of these simulations and experiments should be applicable to the interpretation of dissociation processes in other materials.

原子探针层析技术（APT）的成功应用有赖于对样品质谱（即 m/z 直方图）的准确解读。有些材料产生的质谱可以直接进行峰值分配/范围划分，但也有许多材料产生的质谱具有无法简单解释的特征。其中一个例子是 Ga2O3，它产生的质谱包含几个宽泛而难以解释的特征。在此，我们研究了 GaO2+ → O1++ Ga1+ 的解离过程，并解释了这一解离过程是如何在质谱中产生宽泛且以前未确定的特征的。我们利用现实的静电模型对解离反应进行了轨迹模拟，并与使用市售的直飞和基于反射电子的局部电极（LE）APT 仪器进行的实验进行了比较。结果表明，这些特征的出现在很大程度上取决于飞行时间（ToF）质量分析仪的具体设计。我们探讨了各种实验参数如何影响解离过程在一维（1D）质谱和二维（2D）相关直方图中的表现。虽然这项工作的重点是与 Ga2O3 有关的特定解离过程，但在这些模拟和实验过程中获得的理解应适用于解释其他材料的解离过程。

{"title":"On the instrument-dependent appearance of ion dissociation events in atom probe tomography mass spectra","authors":"Benjamin W. Caplins , Ann N. Chiaramonti , Jacob M. Garcia , Luis Miaja-Avila , Kayla H. Yano , Daniel K. Schreiber , Joseph H. Bunton","doi":"10.1016/j.ultramic.2024.114061","DOIUrl":"10.1016/j.ultramic.2024.114061","url":null,"abstract":"<div><div>The successful application of atom probe tomography (APT) relies on the accurate interpretation of the mass spectrum (<em>i.e.</em> <span><math><mrow><mi>m</mi><mo>/</mo><mi>z</mi></mrow></math></span> histogram) from a sample. Some materials yield mass spectra that are amenable to a straightforward peak assignment/ranging, however, there are many materials that produce mass spectra with features that defy simple interpretation. One such example is Ga<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> which yields mass spectra containing several broad and difficult to interpret features. Herein, we study the GaO<span><math><msup><mrow></mrow><mrow><mn>2</mn><mo>+</mo></mrow></msup></math></span> <span><math><mo>→</mo></math></span> O<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn><mo>+</mo></mrow></msup><mo>+</mo></mrow></math></span> Ga<span><math><msup><mrow></mrow><mrow><mn>1</mn><mo>+</mo></mrow></msup></math></span> dissociation and we explain how this dissociation process gives rise to broad and previously unassigned features in the mass spectrum. Trajectory simulations are performed for the dissociation reaction utilizing realistic electrostatic models and compared to experiments using commercially available straight flight and reflectron based local electrode (LE) APT instruments. It is shown that the appearance of these features is strongly dependent on the specific design of the time-of-flight (ToF) mass analyzer. We explore how various experimental parameters can affect the appearance of the dissociation process in the one-dimensional (1D) mass spectrum and in the two-dimensional (2D) correlation histogram. While the focus of this work is on a particular dissociation process related to Ga<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>, the understanding gained in the course of these simulations and experiments should be applicable to the interpretation of dissociation processes in other materials.</div></div>","PeriodicalId":23439,"journal":{"name":"Ultramicroscopy","volume":"267 ","pages":"Article 114061"},"PeriodicalIF":2.1,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142578087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A refined plan-view specimen preparation technique for high-quality electron microscopy studies of epitaxially grown atomically thin 2D layers 用于对外延生长的原子级二维薄层进行高质量电子显微镜研究的精细平面视图试样制备技术

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-18 DOI: 10.1016/j.ultramic.2024.114063

A.S. Prikhodko , E. Zallo , R. Calarco , N.I. Borgardt

The structural studies of two-dimensional (2D) van der Waals heterostructures and understanding of their relationship with the orientation of crystalline substrates using transmission electron microscopy (TEM) presents a challenge in developing an easy-to-use plan-view specimen preparation technique. In this report, we introduce a simple approach for high-quality plan-view specimen preparation utilizing a dual beam system comprising focused ion beam and scanning electron microscopy.

To protect the atomically thin 2D heterostructure during the preparation process, we employ an epoxy layer. This layer serves as a protective barrier and enables the creation of a TEM specimen comprising a thin substrate fragment with an overgrown 2D structure covered by a thin, electron-transparent epoxy layer. The coexistence of both 2D layers and substrate is essential for investigating the relative crystallographic orientations between the grown 2D structures and the substrates. The thickness of the specimen is monitored using low-voltage scanning electron microscopy.

We apply this technique to prepare plan-view specimens of 2D germanium-antimony-telluride (GST) on Si and hexagonal boron nitride (h-BN)/epitaxial graphene (EG) heterostructures grown on 6H-SiC substrates. The grain-like atomic structure observed in the 2.2 nm thick GST layer on Si substrate provides evidence of the mosaicity of GST during the early stages of epitaxial growth. H-BN/EG on 6H-SiC structural studies indicate a rotation of h-BN/EG around the 6H-SiC[0001] axis by an angle of 30°. The observed BN particles with sizes in the nanometer range on top of the sample have the wurtzite lattice type and random orientation.

The developed specimen preparation technique offers a powerful tool for TEM studies of atomically thin layers on crystals. Its simplicity and ability to provide valuable insights into the in-plane relationships between 2D structures and crystalline substrates make it a promising complement to grazing incident X-ray diffraction.

利用透射电子显微镜（TEM）对二维（2D）范德华异质结构进行结构研究，并了解它们与晶体基底取向的关系，这对开发一种易于使用的平面视图试样制备技术提出了挑战。在本报告中，我们介绍了一种利用双光束系统（包括聚焦离子束和扫描电子显微镜）制备高质量平面视图试样的简单方法。为了在制备过程中保护原子级较薄的二维异质结构，我们采用了环氧树脂层，该层可作为保护屏障，并可制作 TEM 试样，试样由薄基片和生长过的二维结构组成，基片上覆盖着一层薄的电子透明环氧树脂层。二维层和基底的共存对于研究生长的二维结构和基底之间的相对晶体学取向至关重要。我们采用这种技术制备了硅基二维锗锑碲化物 (GST) 和 6H-SiC 基底上生长的六方氮化硼 (h-BN) / 外延石墨烯 (EG) 异质结构的平面视图试样。在硅衬底上 2.2 nm 厚的 GST 层中观察到的晶粒状原子结构证明了 GST 在外延生长早期阶段的镶嵌性。6H-SiC 上的 H-BN/EG 结构研究表明，h-BN/EG 围绕 6H-SiC[0001] 轴旋转了 30°。在样品顶部观察到的尺寸在纳米范围内的 BN 粒子具有渥兹晶格类型和随机取向。所开发的试样制备技术为晶体上原子薄层的 TEM 研究提供了强有力的工具，其简便性和对二维结构与晶体基底之间的面内关系提供有价值见解的能力，使其成为掠入射 X 射线衍射的有力补充。

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引用次数: 0

Development of ultrafast four-dimensional precession electron diffraction 开发超快四维前驱电子衍射。

IF 2.1 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2024-10-18 DOI: 10.1016/j.ultramic.2024.114064

Toshiya Shiratori , Jumpei Koga , Takahiro Shimojima , Kyoko Ishizaka , Asuka Nakamura

Ultrafast electron diffraction/microscopy technique enables us to investigate the nonequilibrium dynamics of crystal structures in the femtosecond-nanosecond time domain. However, the electron diffraction intensities are in general extremely sensitive to the excitation errors (i.e., deviation from the Bragg condition) and the dynamical effects, which had prevented us from quantitatively discussing the crystal structure dynamics particularly in thick samples. Here, we develop a four-dimensional precession electron diffraction (4D-PED) system by which time (t) and electron-incident-angle

(ϕ)

dependences of electron diffraction patterns

(q_{x}, q_{y})

are recorded. Nonequilibrium crystal structure refinement on VTe₂ demonstrates that the ultrafast change in the crystal structure can be quantitatively determined from 4D-PED. We further perform the analysis of the

ϕ

dependence, from which we can qualitatively estimate the change in the reciprocal lattice vector parallel to the optical axis. These results show the capability of the 4D-PED method for the quantitative investigation of ultrafast crystal structural dynamics.

超快电子衍射/显微技术使我们能够在飞秒-纳秒时域内研究晶体结构的非平衡动力学。然而，电子衍射强度通常对激发误差（即偏离布拉格条件）和动力学效应极为敏感，这阻碍了我们定量讨论晶体结构动力学，尤其是厚样品中的晶体结构动力学。在这里，我们开发了一种四维前驱电子衍射（4D-PED）系统，通过它可以记录电子衍射图案（qx,qy）的时间（t）和电子入射角（j）相关性。VTe2 的非平衡晶体结构细化表明，晶体结构的超快变化可以通过 4D-PED 进行定量测定。我们还进一步分析了 ϕ 的相关性，从中可以定性地估计出平行于光轴的倒易点阵矢量的变化。这些结果表明了 4D-PED 方法在定量研究超快晶体结构动力学方面的能力。

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引用次数: 0