Article
Optics
Chengcheng Chang, Xingchen Pan, Hua Tao, Cheng Liu, Suhas P. Veetil, Jianqiang Zhu
Summary: The proposed method utilizes highly tilted illumination and non-paraxial iterative computation to improve image quality of single-shot 3D ptychography. By accurately reconstructing the 3D structure of a thick sample from recorded diffraction patterns using a modified multi-slice algorithm, the fidelity of reconstruction is significantly enhanced. The feasibility of the method is demonstrated through experimental observations guided by numerical simulations.
Article
Nanoscience & Nanotechnology
Mehrdad Abbasi, Yutao Dong, Jun Meng, Dane Morgan, Xudong Wang, Jinwoo Hwang
Summary: The evolution of medium range ordering (MRO) and crystallization behavior of amorphous TiO2 films grown by atomic layer deposition were investigated using in situ four-dimensional scanning transmission electron microscopy. The degree of MRO increases with temperature and reaches the maximum when crystallization starts to occur. In addition, post-annealing only develops a small portion of MRO into crystal nuclei, while the remaining MRO regions undergo structural relaxation. Crystallographic defects within crystal phases were observed, which may affect the corrosion resistance of the film. Understanding and controlling MRO is important for optimizing ALD-grown amorphous films for future functional devices and renewable energy applications.
Article
Materials Science, Multidisciplinary
Drazen Radic, Martin Peterlechner, Matthias Posselt, Hartmut Bracht
Summary: Variable resolution fluctuation electron microscopy experiments were conducted to analyze the medium-range order in self-ion implanted amorphous silicon and amorphous germanium. The commonly used pair-persistence analysis was found to be influenced by experimental conditions. The evaluation of the structural correlation length ξ, a metric for the medium-range order length scale, showed variations depending on the use of energy filtering and sample thickness. Instead, plotting the normalized variance peak magnitude over the electron beam size yielded more reliable results. The evaluated medium-range order extents were approximately (1.50 +/- 0.50) nm for amorphous germanium and (1.10 +/- 0.20) nm for amorphous silicon.
MICROSCOPY AND MICROANALYSIS
(2023)
News Item
Optics
Yuya Morimoto
Summary: A transmission electron microscopy technique allows the recording of movies capturing the dynamic behavior of optical near-fields with a temporal resolution surpassing the oscillation of optical electric fields.
Article
Biochemical Research Methods
Nikita Vladimirov, Friedrich Preusser, Jan Wisniewski, Ziv Yaniv, Ravi Anand Desai, Andrew Woehler, Stephan Preibisch
Summary: Light-sheet fluorescence microscopy has become an essential tool for imaging live developing organisms due to its low toxicity and high resolution, especially when combined with multi-view imaging and microfluidics for precise control experiments and high-content screening.
BIOMEDICAL OPTICS EXPRESS
(2021)
Article
Chemistry, Physical
Jin-Hu Dou, Maxx Q. Arguilla, Yi Luo, Jian Li, Weizhe Zhang, Lei Sun, Jenna L. Mancuso, Luming Yang, Tianyang Chen, Lucas R. Parent, Grigorii Skorupskii, Nicole J. Libretto, Chenyue Sun, Min Chieh Yang, Phat Vinh Dip, Edward J. Brignole, Jeffrey T. Miller, Jing Kong, Christopher H. Hendon, Junliang Sun, Mircea Dinca
Summary: Researchers have successfully grown single crystals of 2D metal-organic frameworks up to 200 µm in size by balancing in-plane and out-of-plane interactions, revealing anisotropic transport and a clear correlation between conductivity and the nature of the metal cation in the sheets.
Editorial Material
Biochemistry & Molecular Biology
Yang Zhang, Hao Jiang, Taoyu Ye, Mario Juhas
Summary: Despite the significant interest in deep learning in microbiology, its full potential is yet to be realized. Deep-learning-based systems are believed to play a crucial role in monitoring and investigating microorganisms in the future.
TRENDS IN MICROBIOLOGY
(2021)
Article
Materials Science, Multidisciplinary
Keita Nomoto, Anna Ceguerra, Christoph Gammer, Bosong Li, Huma Bilal, Anton Hohenwarter, Bernd Gludovatz, Jurgen Eckert, Simon P. Ringer, Jamie J. Kruzic
Summary: The study revealed the hierarchical structure of BMGs through nanobeam electron diffraction experiments, showing that the local hardness of microscale domains decreases with the size and volume fraction of atomic clusters with higher local MRO. A model of ductile phase softening was proposed to enable the design of BMGs in the future by tuning the MRO size and distribution in the nanostructure.
Article
Geosciences, Multidisciplinary
K. Jiang, S. Y. Huang, Z. G. Yuan, Q. Y. Xiong, Y. Y. Wei
Summary: With high-resolution data from the MMS mission, a tilted ion-scale flux rope is observed in the tailward outflow of a magnetic reconnection in the terrestrial magnetotail, indicating the extension of the X-line in the dawn-dusk direction. The observed electron vortex embedded in the flux rope generates an induced magnetic field with the same direction as the axial component, contributing to the enhancement of the magnetic flux carried by the flux rope.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Editorial Material
Chemistry, Physical
Igor A. Pasti, Slavko V. Mentus
Summary: The authors present a new bottom-up strategy for studying the structural evolution of individual nanoparticles and their relationship to structure-stability properties, highlighting the limitations of the standard top-down approach in understanding electrocatalyst stability.
Article
Multidisciplinary Sciences
Tatiana Latychevskaia, Alice Kohli
Summary: A low-dose imaging technique is proposed, where recognition is used instead of recording high-resolution images to verify structural hypotheses. By detecting only a few scattered particles, a structural hypothesis can be confirmed with a probability exceeding 95%. This technique can be applied to optical character recognition and minimizing radiation damage in sensitive materials.
SCIENTIFIC REPORTS
(2022)
Article
Multidisciplinary Sciences
L. Gierz, K. Przybyl
Summary: This study analyzes and evaluates samples of rape, barley, and wheat seeds and creates neural models using machine learning techniques for identification. The results demonstrate that the method can accurately classify seed types and their transportation methods.
SCIENTIFIC REPORTS
(2022)
Article
Physics, Multidisciplinary
Zhongwei Dai, Zhaoli Gao, Sergey S. Pershoguba, Nikhil Tiwale, Ashwanth Subramanian, Qicheng Zhang, Calley Eads, Samuel A. Tenney, Richard M. Osgood, Chang-Yong Nam, Jiadong Zang, A. T. Charlie Johnson, Jerzy T. Sadowski
Summary: The study presents experimental evidence of electronic and optical interlayer resonances in graphene van der Waals heterostructure interfaces. Using spectroscopic mode of a low-energy electron microscope (LEEM) and Raman spectroscopy, researchers found an increase in the interlayer spacing of 30 degrees twisted bilayer graphene and observed a unique type of Fano resonance around the D and G modes of the graphene lattice vibrations. This robust Fano resonance is a direct result of quantum confinement and the interplay between discrete phonon states and the excitonic continuum.
PHYSICAL REVIEW LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Drazen Radic, Martin Peterlechner, Matthias Posselt, Hartmut Bracht
Summary: Fluctuation electron microscopy (FEM) is used to analyze intensity fluctuations in diffraction patterns for studying the structure of amorphous materials. Energy filtered FEM experiments on amorphous germanium show that energy filtering greatly improves the quality of the FEM data by removing unwanted inelastic background intensity. The narrower the energy filter, the closer the energy filtered FEM data is to the ideal conditions.
MICROSCOPY AND MICROANALYSIS
(2023)
Article
Materials Science, Multidisciplinary
Drazen Radic, Martin Peterlechner, Matthias Posselt, Hartmut Bracht
Summary: This study investigates how knock-on displacements influence fluctuation electron microscopy experiments, showing that energy filtering can greatly enhance data quality. By conducting experiments with different cameras and acceleration voltages, the impact of knock-on displacements on the data can be controlled.
MICROSCOPY AND MICROANALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Jenna A. A. Tan, Jordan T. T. Dull, Steven E. E. Zeltmann, Jakhangirkhodja A. A. Tulyagankhodjaev, Holly M. M. Johnson, Alex Liebman-Pelaez, Brendan D. D. Folie, Sven A. A. Donges, Omar Khatib, Jonathan G. G. Raybin, Trevor D. D. Roberts, Leo M. M. Hamerlynck, Christian P. N. Tanner, Jina Lee, Colin Ophus, Karen C. C. Bustillo, Markus B. B. Raschke, Hendrik Ohldag, Andrew M. M. Minor, Barry P. P. Rand, Naomi S. S. Ginsberg
Summary: Multimodal multiscale characterization techniques are used to study organic semiconducting thin films and reveal crystallization mechanisms of different microstructures. The observations show the hybrid crystalline structures in rubrene thin films and the transition to a spherulite morphology. The importance of considering the initial temperature increase during thermal annealing is discovered, and it is found that thermal conditions can significantly affect the crystallization of organic thin films.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
T. W. J. Kwok, T. P. McAuliffe, A. K. Ackerman, B. H. Savitzky, M. Danaie, C. Ophus, D. Dye
Summary: A TWIP steel with a specific composition was deformed to 6% strain and analyzed using 4D-STEM technique. It was found that the average elastic strain parallel and perpendicular to the twinning direction was about 6%, but there were hot spots with even larger strains up to 12%. These hot spots were attributed to a high density of Frank dislocations on the twin boundary. The strain fields in the TWIP steel were significantly larger than other twinning materials, and could explain the early thickness saturation of nanotwins.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Stephanie M. Ribet, Colin Ophus, Roberto dos Reis, Vinayak P. Dravid
Summary: Material properties are affected by defects, and their characterization requires nano- to atomic-scale resolution. 4D-STEM is a versatile technique that uses diffraction patterns to highlight and map defect signals. In this study, virtual detectors were used with multislice simulations to explore different ways of analyzing diffraction patterns. By applying these detectors to graphene and lead titanate samples, local order and defects were effectively studied. Moreover, modifying the electron beam can enhance image contrast and characterize local symmetry.
MICROSCOPY AND MICROANALYSIS
(2023)
Article
Multidisciplinary Sciences
Zezhou Li, Zhiheng Xie, Yao Zhang, Xilong Mu, Jisheng Xie, Hai-Jing Yin, Ya-Wen Zhang, Colin Ophus, Jihan Zhou
Summary: Deciphering the three-dimensional atomic structure of solid-solid interfaces in core-shell nanomaterials is key to understanding their catalytical, optical, and electronic properties. In this study, the authors used atomic resolution electron tomography to investigate the atomic structures of palladium-platinum core-shell nanoparticles at the single-atom level. They found that the core-shell interface is atomically diffuse with an average thickness of 4.2 angstrom, regardless of the particle's morphology or crystallographic texture. The high concentration of Pd in the diffusive interface is related to the dissolution of free Pd atoms from the Pd seeds, as confirmed by cryogenic electron microscopy.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Xuyang Zhou, Ali Ahmadian, Baptiste Gault, Colin Ophus, Christian H. Liebscher, Gerhard Dehm, Dierk Raabe
Summary: Grain boundaries, the defects between differently oriented crystals, play an important role in solute segregation and material properties. The interplay of structure and composition of grain boundaries at the atomic level remains unclear. Through charge-density imaging and atom probe tomography, the authors reveal that the atomic motifs control the chemical properties of grain boundaries and enable the targeted design and passivation for various applications.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Madeline Van Winkle, Isaac M. Craig, Stephen Carr, Medha Dandu, Karen C. Bustillo, Jim Ciston, Colin Ophus, Takashi Taniguchi, Kenji Watanabe, Archana Raja, Sinead M. Griffin, D. Kwabena Bediako
Summary: The authors quantitatively characterized the mechanical deformations of small-angle twisted bilayers and heterobilayers of 2D semiconductors using interferometric 4D scanning transmission electron microscopy. They found that lattice reconstruction and strain accumulation are crucial for defining the electronic structure of two-dimensional moire superlattices. Local rotations dominate relaxation in twisted homobilayers, while local dilations are prominent in heterobilayers with large lattice mismatch. Encapsulation of the moire layers in hBN further enhances and localizes the in-plane reconstruction pathways.
NATURE COMMUNICATIONS
(2023)
Article
Physics, Applied
Juhyeok Lee, Moosung Lee, YongKeun Park, Colin Ophus, Yongsoo Yang
Summary: Electron tomography provides valuable three-dimensional structural information that cannot be observed by two-dimensional imaging. A new method called multislice electron tomography (MSET) based on four-dimensional scanning transmission electron microscopy (STEM) tilt series is developed to overcome the limitations of the annular dark-field (ADF) STEM-based tomography. The MSET method effectively reduces undesirable reconstruction artifacts and allows precise determination of atomic structures with improved sensitivity for low-Z elements at considerably low electron-dose conditions.
PHYSICAL REVIEW APPLIED
(2023)
Article
Materials Science, Multidisciplinary
Kevin J. A. Franke, Colin Ophus, Andreas K. Schmid, Christopher H. Marrows
Summary: We used spin-polarized low-energy electron microscopy to study domain pattern transfer in a multiferroic heterostructure consisting of a (111)-oriented BaTiO3 substrate and an epitaxial Ni film. Interfacial strain transfer and inverse magnetostriction induce a uniaxial in-plane magnetic anisotropy that rotates between alternating stripe regions. Two types of magnetic domain walls can be initialized, and the competition between exchange and magnetostatic energies influences the magnetic domain configuration.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
E. W. C. Terzoudis-Lumsden, T. C. Petersen, H. G. Brown, P. M. Pelz, C. Ophus, S. D. Findlay
Summary: This study proposes a parallax method for three-dimensional structure determination using four-dimensional scanning transmission electron microscopy (STEM) and a wealth of scattering data. The method synthesizes a virtual depth-sectioning reconstruction of the sample structure by determining the scattering matrix. The study explores the use of dark field signal to improve depth resolution and discusses the challenges and limitations of the parallax reconstruction.
MICROSCOPY AND MICROANALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Matthew J. Coupin, Yi Wen, Sungwoo Lee, Anshul Saxena, Colin Ophus, Christopher S. Allen, Angus I. Kirkland, Narayana R. Aluru, Gun-Do Lee, Jamie H. Warner
Summary: Defects in crystalline lattices cause modulation of the atomic density, leading to variations in the associated electrostatics at the nanoscale. Four-dimensional scanning transmission electron microscopy (4D-STEM) was used to measure electric fields near point dislocations in a monolayer, overcoming the challenges of traditional phase contrast imaging. The increased electric field magnitude near the (1,0) edge dislocation core in graphene is shown to arise from long-range interactions beyond the nearest atomic neighbor. These results provide insights into using 4D-STEM for quantifying electrostatics and mapping potential variations in thin materials.
Article
Microscopy
Steven E. Zeltmann, Shang-Lin Hsu, Hamish G. Brown, Sandhya Susarla, Ramamoorthy Ramesh, Andrew M. Minor, Colin Ophus
Summary: Nanobeam electron diffraction is used to probe the local structural properties of complex crystalline materials. A stacked Bloch wave method is developed to model the diffracted intensities from thick samples with varying structure. The method is successfully applied to extract material properties and elucidate complex vortex topologies in multilayer samples.
Article
Multidisciplinary Sciences
Sandhya Susarla, Shanglin Hsu, Fernando Gomez-Ortiz, Pablo Garcia-Fernandez, Benjamin H. Savitzky, Sujit Das, Piush Behera, Javier Junquera, Peter Ercius, Ramamoorthy Ramesh, Colin Ophus
Summary: By using atomic-scale symmetry-breaking operations, the handedness of a material can be engineered in a topological polar vortex ferroelectric/dielectric system. The mapping of the topology-driven three-dimensional domain walls reveals the interplay between perpendicular and parallel polarization, resulting in the formation of triple point topologies. This research is significant for understanding emergent electronic properties and potential applications in quantum sensing.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Samra Husremovic, Berit H. Goodge, Matthew P. Erodici, Katherine Inzani, Alberto Mier, Stephanie M. Ribet, Karen C. Bustillo, Takashi Taniguchi, Kenji Watanabe, Colin Ophus, Sinead M. Griffin, D. Kwabena Bediako
Summary: In this study, researchers demonstrate high-density phase change memory based on phase transition materials. By fabricating H-TaS2/1T-TaS2 heterostructures, they observe optically active heterochirality and correlate it with resistivity steps in the CDW superlattice structure. They also show the role of strain engineering in promoting multi-level switching.
NATURE COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Kevin J. A. Franke, Colin Ophus, Andreas K. Schmid, Christopher H. Marrows
Summary: We present a study on the transfer of domain patterns from a (111)-oriented ferroelectric BaTiO3 substrate to an epitaxial Co film grown on a Pd buffer layer. The transfer is achieved through interfacial strain transfer and inverse magnetostriction, resulting in stripe regions with modulated in-plane uniaxial magnetic anisotropy direction. The formation of two distinct anisotropy configurations between stripe regions is observed, leading to different angles between adjacent domain magnetizations. The study also explores the initialization of different magnetization configurations by applying a magnetic field parallel or perpendicular to the stripes.
Article
Materials Science, Multidisciplinary
Zixuan Guo, Colin Ophus, Karen C. Bustillo, Ryan Fair, Stefan C. B. Mannsfeld, Alejandro L. Briseno, Enrique D. Gomez
Summary: Organic semiconductor materials have versatile applications in electrical devices such as solar cells and transistors. However, controlling the molecular packing at organic-organic interfaces and characterizing buried interlayer morphology is challenging. In this study, we demonstrate the growth of single-crystalline bilayer organic semiconductors on graphene using two small molecules, ZnPc and PTCDA, through vertical physical vapor transport. We use 4D-scanning transmission electron diffraction (4D-STEM) to directly observe the orientation distribution of ZnPc and PTCDA crystallites on graphene, elucidating different growth mechanisms and predicting the morphology of stacked ZnPc/PTCDA heterojunctions.
MRS COMMUNICATIONS
(2023)
