Ultramicroscopy最新文献_第2页

Mode-dependent phonon relaxation in time-resolved electron diffraction pattern simulations 时间分辨电子衍射图样模拟中模式依赖声子弛豫

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2026-01-20 DOI: 10.1016/j.ultramic.2026.114320

Wojciech Marciniak , Joanna Marciniak , José Ángel Castellanos-Reyes , Ján Rusz

Time-resolved pump-probe experiments offer unique possibilities for studying ultrafast processes; however, simulation tools for interpreting phonon dynamics in electron diffraction patterns at the sub-picosecond scale remain limited. We introduce the frozen trajectory excitation (FTE) method of exciting phonons beyond their thermal equilibrium population by modifying a molecular dynamics trajectory in the (

\vec{q}, ω

)-space, and couple it with a new approach to ensemble sampling that extends frozen phonon multislice simulations into the time domain. In this approach, phonons with a certain natural frequency (

ω

) and located within an arbitrarily selected range of phonon wave vector (

\vec{q}

) are first selectively excited within a single molecular dynamics trajectory. Subsequently, several parallel relaxation runs are started at random points, and snapshots from these trajectories serve as inputs for multislice simulations at defined time delays.

We apply this framework to fcc Ni with relaxation time resolution of 10 fs. The simulations reveal multi-phonon scattering processes as well as strong mode dependence in phonon relaxation, highlighting the importance of considering phonon-specific behavior in ultrafast dynamics. Our results show that mode-dependent relaxation leaves measurable signatures in diffraction patterns, providing predictive guidance for future time-resolved TEM studies.

时间分辨泵浦-探针实验为研究超快过程提供了独特的可能性；然而，在亚皮秒尺度上解释电子衍射模式中的声子动力学的模拟工具仍然有限。我们引入了冻结轨迹激发（FTE）方法，通过改变（q→，ω）空间中的分子动力学轨迹来激发声子超越其热平衡种群，并将其与一种新的集成采样方法相结合，将冻结声子多片模拟扩展到时域。在该方法中，首先在单个分子动力学轨迹内选择性地激发具有一定固有频率（ω）且位于任意选择声子波矢量（q→）范围内的声子。随后，在随机点开始几个平行的松弛运行，这些轨迹的快照作为多片模拟的输入，在定义的延迟时间。我们将该框架应用于弛豫时间分辨率为10fs的fcc Ni。模拟揭示了多声子散射过程以及声子弛豫的强模式依赖性，突出了在超快动力学中考虑声子特异性行为的重要性。我们的研究结果表明，模式相关的弛豫在衍射模式中留下了可测量的特征，为未来的时间分辨TEM研究提供了预测指导。

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引用次数: 0

Towards large-area EELS mapping of precipitates in a steel matrix: Comparing low loss and high loss quantification 对钢基体中析出物的大面积EELS映射：比较低损耗和高损耗量化

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2026-01-17 DOI: 10.1016/j.ultramic.2026.114322

Alan J. Craven, Bianca Sala , Ian MacLaren

It is demonstrated that the low loss region of the electron energy loss spectrum can successfully map (V,Ti,Nb)C precipitates in the matrix of a steel including determining their thicknesses, volume, number density, volume fraction and size distribution. A comparison is made of the results obtained using both the low loss (mainly plasmon-type losses and low-lying semi-core-loss edges) and high loss signals (principally more classic core-loss edges) from the same dataset. The agreement between the two sets of results is excellent. While the high loss results are more element specific, the data takes much longer to acquire. When acquiring only the low loss data, the acquisition time is much shorter and would therefore allow mapping of much larger areas of a specimen, with obvious potential for making statistically significant measurements of precipitate size distributions and volume fractions. Provided that an initial study which includes high loss data is made, such large area maps can be quantified. The residual diffraction contrast in the low loss signal also provides a link connecting the precipitates and the microstructure of the matrix. While the approach here is applied to steels, it has potential for much wider applicability.

结果表明，电子能量损失谱的低损失区可以成功地映射钢基体中的（V,Ti,Nb）C析出物，包括确定它们的厚度、体积、数量密度、体积分数和尺寸分布。对来自同一数据集的低损耗信号（主要是等离子体型损耗和低洼半核心损耗边）和高损耗信号（主要是更经典的核心损耗边）的结果进行了比较。两组结果之间的一致性非常好。虽然高损耗结果是更具体的元素，数据需要更长的时间来获取。当只获取低损耗数据时，获取时间要短得多，因此可以绘制试样的更大区域，具有明显的潜力，可以对沉淀尺寸分布和体积分数进行统计上有意义的测量。如果进行了包括高损失数据在内的初步研究，就可以对这种大面积地图进行量化。低损耗信号中的残余衍射对比也提供了连接析出相和基体微观结构的纽带。虽然这里的方法适用于钢，但它具有更广泛的适用性。

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引用次数: 0

Single photon emitters in hBN: Limitations of atomic resolution imaging and potential sources of error hBN中的单光子发射器：原子分辨率成像的限制和潜在的误差来源。

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2026-01-16 DOI: 10.1016/j.ultramic.2026.114318

David Lamprecht , Shrirang Chokappa , Alissa M. Freilinger , Barbara Maria Mayer , Maximilian Melchior , Jana Dzíbelová , Darwin Lorber , Luiz H.G. Tizei , Mathieu Kociak , Clemens Mangler , Lado Filipovic , Jani Kotakoski

There is a growing interest in identifying the origin of single-photon emission in hexagonal boron nitride (hBN), with proposed candidates including boron and nitrogen vacancies as well as carbon substitutional dopants. Because photon emission intensity often increases with sample thickness, hBN flakes used in these studies commonly exceed 30 atomic layers. To identify potential emitters at the atomic scale, annular dark-field scanning transmission electron microscopy (ADF-STEM) is frequently employed. However, due to the intrinsic AA’ stacking of hBN with vertically alternating boron and nitrogen atoms, this approach is complicated even in few-layer systems. Here, we demonstrate using STEM image simulations and experiments that, even under idealized conditions, the intensity differences between boron- and nitrogen-dominated columns and carbon substitutions become indistinguishable at thicknesses beyond 17 atomic layers (ca. 6 nm). While vacancy-type defects can remain detectable at somewhat larger thicknesses, also their detection becomes unreliable at thicknesses typically used in photonic studies. We further show that common residual aberrations, particularly threefold astigmatism, can lead to artificial contrast differences between columns, which may result in misidentification of atomic defects. We systematically study the effects of non-radially symmetric aberrations on multilayer hBN and demonstrate that even small residual threefold astigmatism can significantly distort the STEM contrast, leading to misleading interpretations.

人们对确定六方氮化硼（hBN）中单光子发射的来源越来越感兴趣，提出的候选物质包括硼和氮空位以及碳取代掺杂剂。由于光子发射强度通常随样品厚度的增加而增加，这些研究中使用的hBN薄片通常超过30个原子层。为了在原子尺度上识别潜在的发射体，环形暗场扫描透射电子显微镜（ADF-STEM）经常被使用。然而，由于hBN与垂直交替的硼和氮原子的固有AA'堆叠，即使在少数层体系中，这种方法也很复杂。在这里，我们使用STEM图像模拟和实验证明，即使在理想条件下，硼和氮主导柱和碳取代之间的强度差异在超过17原子层（约6 nm）的厚度上变得难以区分。虽然空缺型缺陷在较大的厚度下仍然可以检测到，但在光子研究中通常使用的厚度下，它们的检测也变得不可靠。我们进一步表明，常见的残余像差，特别是三倍散光，可以导致人为的柱之间的对比度差异，这可能导致原子缺陷的错误识别。我们系统地研究了非径向对称像差对多层hBN的影响，并证明即使很小的残余三倍像差也会显著扭曲STEM对比度，导致误导性解释。

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引用次数: 0

A universal FIB approach for contamination- and damage-free plan-view TEM lamellae using NaCl sacrificial layers 使用NaCl牺牲层对无污染和无损伤的平面透射电镜片层进行FIB分析

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2026-01-13 DOI: 10.1016/j.ultramic.2026.114319

Chen Liu , Jingkai Xu , Qingxiao Wang , Tianchao Guo , Maolin Chen , Dongxing Zheng , Husam N. Alshareef , Xixiang Zhang

The preparation of high-quality plan-view transmission electron microscopy (TEM) lamellae is essential for investigating the in-plane properties of thin films. However, current focused ion beam (FIB) techniques are limited by ion-beam damage, surface contamination, and time-consuming workflows. Here, we introduce NaCl microcrystals as a sacrificial protective layer, which effectively shields the surface from ion irradiation and can be completely removed by simple dissolution in water, leaving a pristine surface. Building on this, we established a universal and streamlined FIB workflow for plan-view lamellae fabrication from thin films that eliminates the need for conventional Pt/C deposition and avoids custom hardware, relying solely on standard commercial components. Using a classic metal multilayer and an ultrathin epitaxial oxide film as representative model systems, we demonstrate that the prepared plan-view lamellae exhibit large uniform areas, preserved film structures, and contamination-free surfaces, enabling reliable surface-sensitive TEM analyses. This time-efficient and user-friendly approach offers a powerful solution for the contamination- and damage-free preparation of plan-view TEM lamellae across diverse thin-film systems, paving the way for in-depth investigations of their in-plane properties.

制备高质量的平面透射电子显微镜（TEM）薄片对于研究薄膜的平面内性质至关重要。然而，目前的聚焦离子束（FIB）技术受到离子束损伤、表面污染和耗时工作流程的限制。在这里，我们引入了NaCl微晶体作为牺牲保护层，它可以有效地保护表面免受离子照射，并且可以通过简单的溶解在水中完全去除，留下原始的表面。在此基础上，我们建立了一个通用的、简化的FIB工作流程，用于从薄膜中制造平面视图片层，消除了传统Pt/C沉积的需要，避免了定制硬件，完全依赖于标准的商业组件。使用经典的金属多层和超薄外延氧化膜作为代表性模型系统，我们证明了制备的平面视图片层具有大的均匀区域，保留了薄膜结构和无污染表面，从而实现了可靠的表面敏感TEM分析。这种时间效率高、用户友好的方法为跨不同薄膜系统的平面视图透射电镜片的无污染和无损伤制备提供了强有力的解决方案，为深入研究其平面内特性铺平了道路。

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引用次数: 0

STEM-EELS study of beam damage in polymers and extra-terrestrial organic matter using direct electron detectors 利用直接电子探测器对聚合物和地外有机物中的光束损伤进行STEM-EELS研究

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2026-01-03 DOI: 10.1016/j.ultramic.2026.114309

Sylvain Laforet , Corentin Le Guillou , Adrien Teurtrie , Maya Marinova , Francisco de la Peña , Anne-Marie Blanchenet , Sylvain Bernard , Hugues Leroux

Characterizing organic compounds using STEM-EELS at high spatial resolution is crucial in materials science and geosciences, especially for organics intricately mixed with minerals at the nanoscale, as is the case in carbonaceous meteorites. However, the high spatial resolution provided by TEM comes with the challenge of electron beam sensitivity, which has long hindered the study of these fragile compounds. Here, we take advantage of direct electron detectors to revisit analytical strategies, searching for the best compromise to prevent beam damage and reach the highest spatial resolution. Our STEM-EELS parametric survey focuses on two reference polymers (PEEK and PES) which differ in their molecular structures and susceptibility to radiation-induced damage. We sequentially acquire low loss and carbon K-edge spectra at low dwell time using a multi-frame protocol, possible thanks to noiseless direct electron detectors. Results show that PES is much more sensitive than PEEK and that the main damage mechanism is radiolysis coupled to recombination. Damage rates are lower when working at an accelerating voltage of 200 keV rather than at 80 keV. Cooling the sample (- 100 °C) helps reducing mass loss and amorphization, but can also lead to the formation of undesired functional groups through recombination. The pixel size affects beam damage independently of the electron dose. Using the fastest dwell-time permitted by the detectors (80 µs) and pixel sizes of 1.5, 7.5, 15 and 30 nm, we show that PEEK resists at 15 nm pixel but is rapidly amorphized at 1 nm while PES is already unstable at 30 nm pixel size. We understand this as damage delocalization effect on successive pixels. The insoluble organic matter extracted from the Orgueil meteorite also appears to better resist damages at 200 keV, but its aliphatic groups are nevertheless affected at pixel size of 15 nm. A reasonable spectral agreement is found between STEM-EELS and synchrotron-based XANES-STXM, paving the road for investigating extra-terrestrial samples such as those returned by space mission from carbonaceous asteroids Ryugu and Bennu.

利用STEM-EELS在高空间分辨率下表征有机化合物在材料科学和地球科学中是至关重要的，特别是在纳米尺度上与矿物复杂混合的有机物，如碳质陨石。然而，TEM提供的高空间分辨率带来了电子束灵敏度的挑战，这长期阻碍了这些易碎化合物的研究。在这里，我们利用直接电子探测器来重新审视分析策略，寻找防止光束损伤和达到最高空间分辨率的最佳折衷方案。我们的STEM-EELS参数调查侧重于两种参考聚合物（PEEK和PES），它们的分子结构和对辐射诱导损伤的易感性不同。我们使用多帧协议在低停留时间下依次获得低损耗和碳k边光谱，这可能要归功于无噪声直接电子探测器。结果表明，聚醚砜（PES）的损伤敏感性明显高于聚醚砜（PEEK），其主要的损伤机制是辐射分解与复合耦合。在200 keV的加速电压下工作比在80 keV的加速电压下工作损坏率更低。冷却样品（- 100°C）有助于减少质量损失和非晶化，但也可能导致通过重组形成不希望的官能团。像素大小对电子束损伤的影响与电子剂量无关。使用检测器允许的最快停留时间（80µs）和1.5、7.5、15和30 nm的像素尺寸，我们发现PEEK在15 nm像素处具有抗蚀性，但在1 nm像素处迅速非晶化，而PES在30 nm像素尺寸时已经不稳定。我们将其理解为对连续像素的损伤脱域效应。从Orgueil陨石中提取的不溶性有机物似乎也能更好地抵抗200 keV的损伤，但其脂肪基团在15 nm像素尺寸下仍然受到影响。在STEM-EELS和基于同步加速器的XANES-STXM之间发现了合理的光谱一致性，为研究诸如从碳质小行星Ryugu和Bennu返回的太空任务等地外样本铺平了道路。

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引用次数: 0

Evaluation of the reproducibility and crystal tracking precision of TEM goniometers in tomography experiments 层析成像实验中TEM测角仪的再现性和晶体跟踪精度评价

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2026-01-03 DOI: 10.1016/j.ultramic.2026.114308

Marco Santucci, Ute Kolb

Nanocrystalline materials are the basis of many novel engineered systems, including batteries, nanocomposites, and glass ceramics. Three-dimensional electron diffraction (3D ED) has become a key technique for structural analysis of such materials, offering clear advantages over conventional X-ray diffraction. Commercial routine 3D ED acquisition allowing for measurements of crystals down to ∼750 nm is now standard, but pushing the measurable size towards a few tens of nanometers introduces new challenges, requiring robust crystal-tracking methods. At this scale, TEM automation, reliable object detection, and high mechanical precision of the goniometer are essential.

PyFast-ADT is introduced as a modular automation framework for 3D ED data collection, extending the measurable size range through improved crystal tracking routines. Its Python architecture enhances shareability and promotes facility automation within the 3D ED and Cryo-EM communities. The PatchworkCC algorithm combines Cross-Correlation with Kalman Filtering to achieve fully automatic crystal tracking with improved accuracy and minimal user supervision. Characterization of goniometer reproducibility revealed a rapid decrease behaviour degrading precision, addressed by the HiPerGonio procedure, which stabilizes performance and supports optimal TEM/sample holder choices.

Together, these developments enable fully automated 3D ED data collection on 25 nm nanocrystals embedded in a glass-ceramic matrix, increasing throughput up to sixfold and advancing reproducible, high-throughput structure determination at the nanometer scale.

纳米晶体材料是许多新型工程系统的基础，包括电池、纳米复合材料和玻璃陶瓷。三维电子衍射（3D ED）已成为这类材料结构分析的关键技术，与传统的x射线衍射相比具有明显的优势。商业常规3D ED采集允许测量低至~ 750nm的晶体现在是标准的，但是将可测量尺寸推向几十纳米引入了新的挑战，需要强大的晶体跟踪方法。在这种规模下，TEM自动化、可靠的目标检测和高机械精度的测角仪是必不可少的。PyFast-ADT是一个用于3D ED数据收集的模块化自动化框架，通过改进的晶体跟踪程序扩展了可测量的尺寸范围。它的Python架构增强了可共享性，并促进了3D ED和Cryo-EM社区的设施自动化。PatchworkCC算法结合了卡尔曼滤波的相互关联，以提高精度和最小的用户监督实现全自动晶体跟踪。对测角仪再现性的表征表明，通过HiPerGonio程序解决了测量精度快速下降的问题，该程序稳定了测量性能，并支持最佳的TEM/样品夹选择。总之，这些发展使嵌入在玻璃陶瓷基体中的25纳米纳米晶体上的全自动3D ED数据收集成为可能，将吞吐量提高了六倍，并在纳米尺度上推进了可重复的高通量结构测定。

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引用次数: 0

Fabrication and characterization of boron-terminated tetravacancies in monolayer hBN using STEM, EELS and electron ptychography 利用STEM、EELS和电子型图技术在单层hBN中制备和表征硼端四空位

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2025-12-26 DOI: 10.1016/j.ultramic.2025.114305

Dana O. Byrne , Stephanie M. Ribet , Demie Kepaptsoglou , Quentin M. Ramasse , Colin Ophus , Frances I. Allen

Tetravacancies in monolayer hexagonal boron nitride (hBN) with consistent edge termination (boron or nitrogen) form triangular nanopores with electrostatic potentials that can be leveraged for applications such as selective ion transport and neuromorphic computing. In order to quantitatively predict the properties of these structures, an atomic-level understanding of their local electronic and chemical environments is required. Moreover, robust methods for their precision manufacture are needed. Here we use electron irradiation in a scanning transmission electron microscope (STEM) at a high dose rate to drive the formation of boron-terminated tetravacancies in monolayer hBN. Characterization of the defects is achieved using aberration-corrected STEM, monochromated electron energy-loss spectroscopy (EELS), and electron ptychography. Z-contrast in STEM and chemical fingerprinting by core-loss EELS enable identification of the edge terminations, while electron ptychography gives insight into structural relaxation of the tetravacancies and provides evidence of enhanced electron density around the defect perimeters indicative of bonding effects.

具有一致边缘终止（硼或氮）的单层六方氮化硼（hBN）中的四空位形成具有静电电位的三角形纳米孔，可用于选择性离子传输和神经形态计算等应用。为了定量地预测这些结构的性质，需要对它们的局部电子和化学环境有一个原子水平的了解。此外，还需要可靠的精密制造方法。在这里，我们在扫描透射电子显微镜（STEM）中使用高剂量率的电子照射来驱动单层hBN中硼端四空位的形成。缺陷的表征是使用像差校正的STEM，单色电子能量损失谱（EELS）和电子型图实现的。STEM中的z对比和核心损耗EELS的化学指纹识别可以识别边缘末端，而电子型图可以深入了解四空位的结构松弛，并提供缺陷周围电子密度增强的证据，表明键合效应。

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引用次数: 0

A correlation-based optimization model to recover lost and distorted data from scanning tunneling microscopy images based on density functional theory 基于密度泛函理论的扫描隧道显微图像丢失和畸变数据恢复相关优化模型

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2025-12-25 DOI: 10.1016/j.ultramic.2025.114306

Ehsan Moradpur-Tari , Andreas Kyritsakis , Mohadeseh Karimkhah , Veronika Zadin

Scanning tunneling microscopy (STM) has significantly influenced the fields of nanoscience and nanotechnology. However, the tip effect and thermal drift cause loss and distortion of data in the STM images. Here, we propose a physics-guided optimization model for extracting STM imaging parameters, including tip shape, thermal drift, depth of field, current, and height. The model uses partial charge densities from density functional theory (DFT) simulation and works based on the mass comparison of experimental and simulated images using a two-dimensional Pearson correlation. Testing the model on Si(111)-7 × 7 reconstruction images provided higher than 96 % correlations for both biases. The fitting showed the highest correlation for only two bands in each image instead of the integration of all bands. Gaussian functions were used in the model to simulate the tip effect, which could recover 1.5-6 % of the lost data due to the blurring effect. Additionally, thermal drift was detected and corrected in the negative bias image, which could linearly distort the data by about 19 %. An important advantage of using this model is increasing the microscopy speed because there is no need to slow down the scanning process in microscopy experiments to evade thermal drift.

扫描隧道显微镜（STM）对纳米科学和纳米技术领域产生了重大影响。然而，尖端效应和热漂移会导致STM图像中的数据丢失和失真。在这里，我们提出了一个物理导向的优化模型，用于提取STM成像参数，包括尖端形状，热漂移，景深，电流和高度。该模型使用密度泛函理论（DFT）模拟的部分电荷密度，并基于使用二维Pearson相关的实验和模拟图像的质量比较。在Si(111)-7 × 7重建图像上测试模型，两种偏差的相关性均高于96%。拟合显示，每张图像中只有两个波段的相关性最高，而不是所有波段的整合。模型中采用高斯函数模拟尖端效应，可以恢复因模糊效应而丢失的1.5- 6%的数据。此外，在负偏置图像中检测并校正了热漂移，这可能使数据线性扭曲约19%。使用该模型的一个重要优点是提高了显微镜速度，因为在显微镜实验中不需要放慢扫描过程来逃避热漂移。

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引用次数: 0

Assessing the electric field sensitivity measured by pixelated differential phase contrast imaging in vacuum both in the absence of external fields and under field-bound conditions 评估在没有外场和场边界条件下真空中像素化差相衬成像测量的电场灵敏度

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2025-12-25 DOI: 10.1016/j.ultramic.2025.114307

Pierpaolo Ranieri , Reinis Ignatans , Victor Boureau , Vasiliki Tileli

Pixelated differential phase contrast (DPC) is a four-dimensional scanning transmission electron microscopy (4D-STEM) technique in which the position of the transmitted beam is tracked to reconstruct the electromagnetic fields of a sample. Although it can provide (semi-) quantitative information for a range of different applications, the measurements are greatly affected by the microscope’s optical and acquisition settings in terms of sensitivity, accuracy, and spatial resolution, particularly when measuring weak electric fields. Herein, we focus on the nano-beam 4D-STEM configuration and systematically study the way in which all the parameters typically selected by users for pixelated-DPC experiments influence the lowest achievable electric field sensitivity. First, we define the metric by which the sensitivity is assessed, discussing the optimal ranges for parameters including convergence semi-angle, electron dose, and camera length in absence of external field, while also evaluating the effect of the scanning system. Next, the sensitivity and its error are assessed under field-bound conditions, realized by a coplanar capacitor that allows the position of the transmitted beam to be shifted controllably using an external bias. Comparison of the experimental results with finite element method calculations yields quantitative information about the accuracy that can be attained for these measurements, while the effects of microscope drift and sample charging are also discussed. Our findings provide a platform for the quantitative assessment of weak electric fields as calculated by pixelated-DPC experiments, while highlighting the challenges associated with these measurements.

像素化差相对比（DPC）是一种四维扫描透射电子显微镜（4D-STEM）技术，通过跟踪透射光束的位置来重建样品的电磁场。虽然它可以为一系列不同的应用提供（半）定量信息，但在灵敏度、精度和空间分辨率方面，测量结果受到显微镜光学和采集设置的极大影响，特别是在测量弱电场时。本文以纳米束4D-STEM结构为研究对象，系统地研究了像素化dpc实验中用户通常选择的所有参数对可实现的最低电场灵敏度的影响。首先，我们定义了评估灵敏度的度量，讨论了在没有外场的情况下，会聚半角、电子剂量和相机长度等参数的最佳范围，同时还评估了扫描系统的效果。接下来，在场界条件下评估灵敏度及其误差，通过共面电容器实现，该共面电容器允许使用外部偏压可控地移动发射光束的位置。将实验结果与有限元法计算结果进行比较，可以获得有关这些测量精度的定量信息，同时还讨论了显微镜漂移和样品充电的影响。我们的研究结果为通过像素化dpc实验计算的弱电场的定量评估提供了一个平台，同时强调了与这些测量相关的挑战。

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引用次数: 0

Angular resolution enhancement of electron backscatter diffraction patterns 电子后向散射衍射图的角分辨率增强。

IF 2 3区工程技术 Q2 MICROSCOPY

Ultramicroscopy

Pub Date : 2025-12-21 DOI: 10.1016/j.ultramic.2025.114304

T. Ben Britton, Tianbi Zhang

We present a simple ‘shift and add’ based improvement in the angular resolution of single electron backscatter diffraction (EBSD) patterns. Sub-pixel image registration is used to measure the (sub-pixel) difference in projection parameters for patterns collected within a map, and then the pattern is shifted and added together. The resultant EBSD-pattern is shown to contain more angular information than a long-exposure single pattern, via 2D Fast Fourier Transform (FFT)-based analysis. In particular, this method has the potential to enhance the scope of small compact direct electron detectors (DEDs).

我们提出了一种简单的基于“移位和添加”的方法来提高单电子背散射衍射（EBSD）图的角分辨率。采用亚像素配准的方法，对地图中采集到的图案进行投影参数（亚像素）差的测量，然后对图案进行平移和叠加。通过基于二维快速傅里叶变换（FFT）的分析，结果显示ebsd模式比长时间曝光的单一模式包含更多的角度信息。特别是，这种方法有可能提高小型紧凑型直接电子探测器（DEDs）的范围。

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