1
|
Nordahl G, Nord M. Improving Magnetic STEM- Differential Phase Contrast Imaging using Precession. Microsc Microanal 2023; 29:574-579. [PMID: 37749725 DOI: 10.1093/micmic/ozad001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 11/18/2022] [Accepted: 01/01/2023] [Indexed: 09/27/2023]
Abstract
Differential phase contrast in scanning transmission electron microscopy (STEM-DPC) is a technique used to image electromagnetic fields in materials. STEM-DPC is based on tracking the minute changes in the position of the bright-field disk, so any effects which cause inhomogeneities in the intensity or geometry of the disk can lead to the contrast from the electromagnetic fields to be obscured. Structural changes, like grain boundaries, thickness variations, or local crystallographic orientation, are a major cause of these inhomogeneities. In this paper, we present how precession of the STEM probe with the objective lens turned off, providing a near field-free environment for magnetic imaging, can average out nonsystematic inhomogeneities in the electron beam. The methodology was tested on a polycrystalline Fe60Al40 thin film with embedded ferromagnetic structures. The effect of precession was assessed on magnetic induction maps created by three different processing algorithms. Results demonstrate that precessed STEM-DPC with the objective lens turned off shows an improvement in the form of smoothing of the variations found in the DPC signal arising from the underlying polycrystalline background.
Collapse
Affiliation(s)
- Gregory Nordahl
- Department of Physics, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway
| | | |
Collapse
|
2
|
Quinn PD, Cacho-Nerin F, Gomez-Gonzalez MA, Parker JE, Poon T, Walker JM. Differential phase contrast for quantitative imaging and spectro-microscopy at a nanoprobe beamline. J Synchrotron Radiat 2023; 30:200-207. [PMID: 36601938 PMCID: PMC9814065 DOI: 10.1107/s1600577522010633] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 11/04/2022] [Indexed: 06/13/2023]
Abstract
The interaction of a focused X-ray beam with a sample in a scanning probe experiment can provide a variety of information about the interaction volume. In many scanning probe experiments X-ray fluorescence (XRF) is supplemented with measurements of the transmitted or scattered intensity using a pixelated detector. The automated extraction of different signals from an area pixelated detector is described, in particular the methodology for extracting differential phase contrast (DPC) is demonstrated and different processing methods are compared across a range of samples. The phase shift of the transmitted X-ray beam by the sample, extracted from DPC, is also compared with ptychography measurements to provide a qualitative and quantitative comparison. While ptychography produces a superior image, DPC can offer a simple, flexible method for phase contrast imaging which can provide fast results and feedback during an experiment; furthermore, for many science problems, such as registration of XRF in a lighter matrix, DPC can provide sufficient information to meet the experimental aims. As the DPC technique is a quantitative measurement, it can be expanded to spectroscopic studies and a demonstration of DPC for spectro-microscopy measurements is presented. Where ptychography can separate the absorption and phase shifts by the sample, quantitative interpretation of a DPC image or spectro-microscopy signal can only be performed directly when absorption is negligible or where the absorption contribution is known and the contributions can be fitted.
Collapse
Affiliation(s)
- Paul D. Quinn
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Fernando Cacho-Nerin
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Miguel A. Gomez-Gonzalez
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Julia E. Parker
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Timothy Poon
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| | - Jessica M. Walker
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, United Kingdom
| |
Collapse
|
3
|
He L, Shao M, Yang X, Si L, Jiang M, Wang T, Ke Z, Peng T, Fang S, Zhang S, Ouyang X, Zhao G, Zhou J. Morphology Analysis of Unlabeled Red Blood Cells based on Quantitative Differential Phase Contrast Microscopy. Cytometry A 2022; 101:648-657. [PMID: 35243761 DOI: 10.1002/cyto.a.24546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 02/06/2022] [Accepted: 02/25/2022] [Indexed: 11/10/2022]
Abstract
The current classical blood smear technique to observe the morphology of single red blood cells (RBCs) for classification is a laborious and error-prone process. To objectively evaluate the morphology of blood cells, we established a method of computational imaging based on a programmable light emitting diode (LED) array. By using quantitative differential phase contrast (qDPC), we characterized the morphology of unlabeled RBCs as well as blood smears. By focusing on comparing the difference of imaging between unlabeled RBCs and stained RBCs under multi-mode microscopic imaging technology, we demonstrated that qDPC could clearly differentiate discocytes and spherocytes in both unlabeled RBCs and blood smears. The phase map provided by QPI further enhanced the classification accuracy. According to statistical analysis from morphological indexes, the qDPC imaging has a significantly improvement in non-circularity, texture inhomogeneity and equivalent diameters of cells. Thus, this method has a significant superiority in the capability to analyze the morphology of RBCs and could be applied to clinical assays for determining morphological, functional, and structural deterioration of RBCs.
Collapse
Affiliation(s)
- Linna He
- Anhui Medical University, Research and Engineering Center of Biomedical Materials, School of Biomedical Engineering, Hefei, Anhui, China
| | - Meng Shao
- Anhui Medical University, Research and Engineering Center of Biomedical Materials, School of Biomedical Engineering, Hefei, Anhui, China
| | - Xiao Yang
- Anhui Medical University, Research and Engineering Center of Biomedical Materials, School of Biomedical Engineering, Hefei, Anhui, China
| | - Li Si
- The first Affiliated Hospital of Anhui Medical University, Clinical Laboratory Department, Hefei, Anhui, China
| | - Mengduo Jiang
- Anhui Medical University, Research and Engineering Center of Biomedical Materials, School of Biomedical Engineering, Hefei, Anhui, China
| | - Tao Wang
- Anhui Medical University, Research and Engineering Center of Biomedical Materials, School of Biomedical Engineering, Hefei, Anhui, China
| | - Zeyu Ke
- Anhui Medical University, Research and Engineering Center of Biomedical Materials, School of Biomedical Engineering, Hefei, Anhui, China
| | - Tao Peng
- Anhui Medical University, Research and Engineering Center of Biomedical Materials, School of Biomedical Engineering, Hefei, Anhui, China
| | - Shu Fang
- Anhui Medical University, Research and Engineering Center of Biomedical Materials, School of Biomedical Engineering, Hefei, Anhui, China
| | - Shengzhao Zhang
- Anhui Medical University, Research and Engineering Center of Biomedical Materials, School of Biomedical Engineering, Hefei, Anhui, China
| | - Xilin Ouyang
- The Fourth Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Gang Zhao
- University of Science and Technology of China, Department of Electronic Science and Technology, Hefei, Anhui, China
| | - Jinhua Zhou
- Anhui Medical University, Research and Engineering Center of Biomedical Materials, School of Biomedical Engineering, Hefei, Anhui, China
| |
Collapse
|
4
|
Zachman MJ, Yang Z, Du Y, Chi M. Robust Atomic-Resolution Imaging of Lithium in Battery Materials by Center-of-Mass Scanning Transmission Electron Microscopy. ACS Nano 2022; 16:1358-1367. [PMID: 35000379 DOI: 10.1021/acsnano.1c09374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The performance of energy storage materials is often governed by their structure at the atomic scale. Conventional electron microscopy can provide detailed information about materials at these length scales, but direct imaging of light elements such as lithium presents a challenge. While several recent techniques allow lithium columns to be distinguished, these typically either involve complex contrast mechanisms that make image interpretation difficult or require significant expertise to perform. Here, we demonstrate how center-of-mass scanning transmission electron microscopy (CoM-STEM) provides an enhanced ability for simultaneous imaging of lithium and heavier element columns in lithium ion conductors. Through a combination of experiments and multislice electron scattering calculations, we show that CoM-STEM is straightforward to perform and produces directly interpretable contrast for thin samples, while being more robust to variations in experimental parameters than previously demonstrated techniques. As a result, CoM-STEM is positioned to become a reliable and facile method for directly probing all elements within energy storage materials at the atomic scale.
Collapse
Affiliation(s)
- Michael J Zachman
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Zhenzhong Yang
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Yingge Du
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Miaofang Chi
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| |
Collapse
|
5
|
Calderon V S, Ferreira RV, Taneja D, Jayanth RT, Zhou L, Ribeiro RM, Akinwande D, Ferreira PJ. Atomic Electrostatic Maps of Point Defects in MoS 2. Nano Lett 2021; 21:10157-10164. [PMID: 34846155 DOI: 10.1021/acs.nanolett.1c02334] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
In this study, we use differential phase contrast images obtained by scanning transmission electron microscopy combined with computer simulations to map the atomic electrostatic fields of MoS2 monolayers and investigate the effect of sulfur monovacancies and divancancies on the atomic electric field and total charge distribution. A significant redistribution of the electric field in the regions containing defects is observed, with a progressive decrease in the strength of the projected electric field for each sulfur atom removed from its position. The electric field strength at the sulfur monovacancy sites is reduced by approximately 50% and nearly vanishes at the divacancy sites, where it drops to around 15% of the original value, demonstrating the tendency of these defects to attract positively charged ions or particles. In addition, the absence of the sulfur atoms leads to an inversion in the polarity of the total charge distribution in these regions.
Collapse
Affiliation(s)
- Sebastian Calderon V
- INL, International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga s/n, 4715-330 Braga, Portugal
| | - Rafael V Ferreira
- INL, International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga s/n, 4715-330 Braga, Portugal
- Mechanical Engineering Department and IDMEC, Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Deepyanti Taneja
- Microelectronics Research Center, Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas 78758, United States
| | - R T Jayanth
- Microelectronics Research Center, Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas 78758, United States
| | - Langyan Zhou
- Microelectronics Research Center, Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas 78758, United States
| | - Ricardo M Ribeiro
- INL, International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga s/n, 4715-330 Braga, Portugal
- Department and Centre of Physics, University of Minho, Campus of Gualtar, 4710-057 Braga, Portugal
| | - Deji Akinwande
- Microelectronics Research Center, Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas 78758, United States
- Materials Science and Engineering Program, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Paulo J Ferreira
- INL, International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga s/n, 4715-330 Braga, Portugal
- Materials Science and Engineering Program, The University of Texas at Austin, Austin, Texas 78712, United States
- Mechanical Engineering Department and IDMEC, Instituto Superior Técnico, University of Lisbon, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| |
Collapse
|
6
|
Abstract
Recent advances in scanning transmission electron microscopy (STEM) have rekindled interest in multi-channel detectors and prompted the exploration of unconventional scan patterns. These emerging needs are not yet addressed by standard commercial hardware. The system described here incorporates a flexible scan generator that enables exploration of low-acceleration scan patterns, while data are recorded by a scalable eight-channel array of nonmultiplexed analog-to-digital converters. System integration with SerialEM provides a flexible route for automated acquisition protocols including tomography. Using a solid-state quadrant detector with additional annular rings, we explore the generation and detection of various STEM contrast modes. Through-focus bright-field scans relate to phase contrast, similarly to wide-field TEM. More strikingly, comparing images acquired from different off-axis detector elements reveals lateral shifts dependent on defocus. Compensation of this parallax effect leads to decomposition of integrated differential phase contrast (iDPC) to separable contributions relating to projected electric potential and to defocus. Thus, a single scan provides both a computationally refocused phase contrast image and a second image in which the signed intensity, bright or dark, represents the degree of defocus.
Collapse
Affiliation(s)
- Shahar Seifer
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot7610001, Israel
| | - Lothar Houben
- Chemical Research Support Department, Weizmann Institute of Science, Rehovot7610001, Israel
| | - Michael Elbaum
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot7610001, Israel
| |
Collapse
|
7
|
Murthy AA, Ribet SM, Stanev TK, Liu P, Watanabe K, Taniguchi T, Stern NP, Reis RD, Dravid VP. Spatial Mapping of Electrostatic Fields in 2D Heterostructures. Nano Lett 2021; 21:7131-7137. [PMID: 34448396 PMCID: PMC9416602 DOI: 10.1021/acs.nanolett.1c01636] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
In situ electron microscopy is an effective tool for understanding the mechanisms driving novel phenomena in 2D structures. However, due to practical challenges, it is difficult to address these technologically relevant 2D heterostructures with electron microscopy. Here, we use the differential phase contrast (DPC) imaging technique to build a methodology for probing local electrostatic fields during electrical operation with nanoscale spatial resolution in such materials. We find that, by combining a traditional DPC setup with a high-pass filter, we can largely eliminate electric fluctuations emanating from short-range atomic potentials. Using a method based on this filtering algorithm, a priori electric field expectations can be directly compared with experimentally derived values to readily identify inhomogeneities and potentially problematic regions. We use this platform to analyze the electric field and charge density distribution across layers of hBN and MoS2.
Collapse
Affiliation(s)
- Akshay A Murthy
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
- International Institute of Nanotechnology, Northwestern University, Evanston, Illinois 60208, United States
| | - Stephanie M Ribet
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
- International Institute of Nanotechnology, Northwestern University, Evanston, Illinois 60208, United States
| | - Teodor K Stanev
- Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208, United States
| | - Pufan Liu
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Kenji Watanabe
- Research Center for Functional Materials, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Nathaniel P Stern
- Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208, United States
| | - Roberto Dos Reis
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
- The NUANCE Center, Northwestern University, Evanston, Illinois 60208, United States
| | - Vinayak P Dravid
- Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, United States
- International Institute of Nanotechnology, Northwestern University, Evanston, Illinois 60208, United States
- The NUANCE Center, Northwestern University, Evanston, Illinois 60208, United States
| |
Collapse
|
8
|
Elangovan H, Barzilay M, Huang J, Liu S, Cohen S, Ivry Y. Engineering Individual Oxygen Vacancies: Domain-Wall Conductivity and Controllable Topological Solitons. ACS Nano 2021; 15:13380-13388. [PMID: 34355902 PMCID: PMC8631733 DOI: 10.1021/acsnano.1c03623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 08/03/2021] [Indexed: 06/13/2023]
Abstract
Nanoscale devices that utilize oxygen vacancies in two-dimensional metal-oxide structures garner much attention due to conductive, magnetic, and even superconductive functionalities they exhibit. Ferroelectric domain walls have been a prominent recent example because they serve as a hub for topological defects and hence are attractive for next-generation data technologies. However, owing to the light weight of oxygen atoms and localized effects of their vacancies, the atomic-scale electrical and mechanical influence of individual oxygen vacancies has remained elusive. Here, stable individual oxygen vacancies were engineered in situ at domain walls of seminal titanate perovskite ferroics. The atomic-scale electric-field, charge, dipole-moment, and strain distribution around these vacancies were characterized by combining advanced transmission electron microscopy and first-principle methodologies. The engineered vacancies were used to form quasi-linear quadrupole topological defects. Significant intraband states were found in the unit cell of the engineered vacancies, proposing a meaningful domain-wall conductivity for miniaturized data-storage applications. Reduction of the Ti ion as well as enhanced charging and electric-field concentration were demonstrated near the vacancy. A 3-5% tensile strain was observed at the immediate surrounding unit cells of the vacancies. Engineering individual oxygen vacancies and topological solitons thus offers a platform for predetermining both atomic-scale and global functional properties of device miniaturization in metal oxides.
Collapse
Affiliation(s)
- Hemaprabha Elangovan
- Department
of Materials Science and Engineering, Technion−Israel
Institute of Technology, Haifa 3200003, Israel
- Solid
State Institute, Technion−Israel
Institute of Technology, Haifa 3200003, Israel
| | - Maya Barzilay
- Department
of Materials Science and Engineering, Technion−Israel
Institute of Technology, Haifa 3200003, Israel
- Solid
State Institute, Technion−Israel
Institute of Technology, Haifa 3200003, Israel
| | - Jiawei Huang
- School
of Science, Westlake University, Hangzhou, Zhejiang 310024, China
- Institute
of Natural Sciences, Westlake Institute
for Advanced Study, Hangzhou, Zhejiang 310024, China
- Key
Laboratory for Quantum Materials of Zhejiang Province, Hangzhou, Zhejiang 310024, China
| | - Shi Liu
- School
of Science, Westlake University, Hangzhou, Zhejiang 310024, China
- Institute
of Natural Sciences, Westlake Institute
for Advanced Study, Hangzhou, Zhejiang 310024, China
- Key
Laboratory for Quantum Materials of Zhejiang Province, Hangzhou, Zhejiang 310024, China
| | - Shai Cohen
- Nuclear
Research Centre-Negev, Beer-Sheva 84190, Israel
| | - Yachin Ivry
- Department
of Materials Science and Engineering, Technion−Israel
Institute of Technology, Haifa 3200003, Israel
- Solid
State Institute, Technion−Israel
Institute of Technology, Haifa 3200003, Israel
| |
Collapse
|
9
|
Vogel A, Sarott MF, Campanini M, Trassin M, Rossell MD. Monitoring Electrical Biasing of Pb(Zr 0.2Ti 0.8)O 3 Ferroelectric Thin Films In Situ by DPC-STEM Imaging. Materials (Basel) 2021; 14:4749. [PMID: 34443272 PMCID: PMC8400982 DOI: 10.3390/ma14164749] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 08/18/2021] [Accepted: 08/19/2021] [Indexed: 11/17/2022]
Abstract
Increased data storage densities are required for the next generation of nonvolatile random access memories and data storage devices based on ferroelectric materials. Yet, with intensified miniaturization, these devices face a loss of their ferroelectric properties. Therefore, a full microscopic understanding of the impact of the nanoscale defects on the ferroelectric switching dynamics is crucial. However, collecting real-time data at the atomic and nanoscale remains very challenging. In this work, we explore the ferroelectric response of a Pb(Zr0.2Ti0.8)O3 thin film ferroelectric capacitor to electrical biasing in situ in the transmission electron microscope. Using a combination of high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and differential phase contrast (DPC)-STEM imaging we unveil the structural and polarization state of the ferroelectric thin film, integrated into a capacitor architecture, before and during biasing. Thus, we can correlate real-time changes in the DPC signal with the presence of misfit dislocations and ferroelastic domains. A reduction in the domain wall velocity of 24% is measured in defective regions of the film when compared to predominantly defect-free regions.
Collapse
Affiliation(s)
- Alexander Vogel
- Electron Microscopy Center, Empa, Swiss Federal Laboratories for Material Science and Technology, 8600 Dübendorf, Switzerland;
| | - Martin F. Sarott
- Department of Materials, Eidgenössische Technische Hochschule Zürich, 8093 Zürich, Switzerland; (M.F.S.); (M.T.)
| | - Marco Campanini
- Electron Microscopy Center, Empa, Swiss Federal Laboratories for Material Science and Technology, 8600 Dübendorf, Switzerland;
| | - Morgan Trassin
- Department of Materials, Eidgenössische Technische Hochschule Zürich, 8093 Zürich, Switzerland; (M.F.S.); (M.T.)
| | - Marta D. Rossell
- Electron Microscopy Center, Empa, Swiss Federal Laboratories for Material Science and Technology, 8600 Dübendorf, Switzerland;
| |
Collapse
|
10
|
Inamoto S, Shimomura S, Otsuka Y. Electrostatic potential imaging of phase-separated structures in organic materials via differential phase contrast scanning transmission electron microscopy. Microscopy (Oxf) 2020. [PMID: 32453389 DOI: 10.1093/jmicro/dfaa027.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Electron staining is generally performed prior to observing organic materials via transmission electron microscopy (TEM) to enhance image contrast. However, electron staining can deteriorate organic materials. Here, we demonstrate electrostatic potential imaging of organic materials via differential phase contrast (DPC) scanning transmission electron microscopy (STEM) without electron staining. Electrostatic potential imaging drastically increases the contrast between different materials. Phase-separated structures in a poly (3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) blend that are impossible to observe using conventional STEM are clearly visualized. Furthermore, annealing behavior of the phase-separated structures is directly observed. The morphological transformations in the samples are consistent with their physical parameters, including their glass transition and melting temperatures. Our results indicate that electrostatic potential imaging is highly effective for observing organic materials.
Collapse
Affiliation(s)
- Shin Inamoto
- Morphological Research Laboratory, Toray Research Center, Inc., 3-7, Sonoyama 3-chome, Otsu, Shiga 520-8567, Japan
| | - Satoru Shimomura
- Advanced Materials Research Laboratories, Toray Industries, Inc., 2-1, Sonoyama 3-chome, Otsu, Shiga 520-0842, Japan
| | - Yuji Otsuka
- Morphological Research Laboratory, Toray Research Center, Inc., 3-7, Sonoyama 3-chome, Otsu, Shiga 520-8567, Japan
| |
Collapse
|
11
|
Murakami YO, Seki T, Kinoshita A, Shoji T, Ikuhara Y, Shibata N. Magnetic-structure imaging in polycrystalline materials by specimen-tilt series averaged DPC STEM. ACTA ACUST UNITED AC 2020; 69:312-320. [PMID: 32455425 DOI: 10.1093/jmicro/dfaa029] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 05/12/2020] [Accepted: 05/14/2020] [Indexed: 11/15/2022]
Abstract
Differential phase contrast (DPC) imaging in scanning transmission electron microscopy is a technique to visualize electromagnetic field distribution inside specimens at high spatial resolution. However, diffraction contrast strongly hampers electromagnetic contrast in DPC images especially in polycrystalline samples. In this paper, we develop an imaging technique to effectively suppress diffraction contrast in DPC images. It is shown that a magnetic structure in a Nd-Fe-B permanent magnet was clearly visualized by averaging 64 DPC images with various specimen-tilt conditions. This is because the diffraction contrast in DPC images sensitively and randomly varies with crystal orientation and thus almost vanishes by averaging specimen-tilt image series. We further investigated two types of residual diffraction contrast in the tilt-series averaged DPC images: weak contrast inside grains and strong contrast at grain boundaries. We found that the former can be suppressed by averaging more DPC images, whereas the latter can be suppressed by the tilt-series averaging with wider range of specimen tilt. The tilt-series averaging method enables DPC to visualize electromagnetic structures even inside polycrystalline materials.
Collapse
Affiliation(s)
- Yoshiki O Murakami
- Institute of Engineering Innovation, The University of Tokyo, 2-11-16, Yayoi, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Takehito Seki
- Institute of Engineering Innovation, The University of Tokyo, 2-11-16, Yayoi, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Akihito Kinoshita
- Advanced Material Engineering Division, Toyota Motor Corporation, 1200, Mishuku, Susono, Shizuoka 410-1193, Japan
| | - Tetsuya Shoji
- Advanced Material Engineering Division, Toyota Motor Corporation, 1200, Mishuku, Susono, Shizuoka 410-1193, Japan
| | - Yuichi Ikuhara
- Nano Structures Research Laboratory, Japan Fine Ceramics Center, 2-4-1 Matsuno, Atsuta-ku, Nagoya 456-8587, Japan
| | - Naoya Shibata
- Institute of Engineering Innovation, The University of Tokyo, 2-11-16, Yayoi, Bunkyo-ku, Tokyo 113-8656, Japan
| |
Collapse
|
12
|
Murakami YO, Seki T, Kinoshita A, Shoji T, Ikuhara Y, Shibata N. Magnetic-structure imaging in polycrystalline materials by specimen-tilt series averaged DPC STEM. Microscopy (Oxf) 2020. [PMID: 32455425 DOI: 10.1093/jmicro/dfaa029.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Differential phase contrast (DPC) imaging in scanning transmission electron microscopy is a technique to visualize electromagnetic field distribution inside specimens at high spatial resolution. However, diffraction contrast strongly hampers electromagnetic contrast in DPC images especially in polycrystalline samples. In this paper, we develop an imaging technique to effectively suppress diffraction contrast in DPC images. It is shown that a magnetic structure in a Nd-Fe-B permanent magnet was clearly visualized by averaging 64 DPC images with various specimen-tilt conditions. This is because the diffraction contrast in DPC images sensitively and randomly varies with crystal orientation and thus almost vanishes by averaging specimen-tilt image series. We further investigated two types of residual diffraction contrast in the tilt-series averaged DPC images: weak contrast inside grains and strong contrast at grain boundaries. We found that the former can be suppressed by averaging more DPC images, whereas the latter can be suppressed by the tilt-series averaging with wider range of specimen tilt. The tilt-series averaging method enables DPC to visualize electromagnetic structures even inside polycrystalline materials.
Collapse
Affiliation(s)
- Yoshiki O Murakami
- Institute of Engineering Innovation, The University of Tokyo, 2-11-16, Yayoi, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Takehito Seki
- Institute of Engineering Innovation, The University of Tokyo, 2-11-16, Yayoi, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Akihito Kinoshita
- Advanced Material Engineering Division, Toyota Motor Corporation, 1200, Mishuku, Susono, Shizuoka 410-1193, Japan
| | - Tetsuya Shoji
- Advanced Material Engineering Division, Toyota Motor Corporation, 1200, Mishuku, Susono, Shizuoka 410-1193, Japan
| | - Yuichi Ikuhara
- Nano Structures Research Laboratory, Japan Fine Ceramics Center, 2-4-1 Matsuno, Atsuta-ku, Nagoya 456-8587, Japan
| | - Naoya Shibata
- Institute of Engineering Innovation, The University of Tokyo, 2-11-16, Yayoi, Bunkyo-ku, Tokyo 113-8656, Japan
| |
Collapse
|
13
|
Inamoto S, Shimomura S, Otsuka Y. Electrostatic potential imaging of phase-separated structures in organic materials via differential phase contrast scanning transmission electron microscopy. ACTA ACUST UNITED AC 2020; 69:304-311. [PMID: 32453389 DOI: 10.1093/jmicro/dfaa027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 05/12/2020] [Accepted: 05/14/2020] [Indexed: 11/13/2022]
Abstract
Electron staining is generally performed prior to observing organic materials via transmission electron microscopy (TEM) to enhance image contrast. However, electron staining can deteriorate organic materials. Here, we demonstrate electrostatic potential imaging of organic materials via differential phase contrast (DPC) scanning transmission electron microscopy (STEM) without electron staining. Electrostatic potential imaging drastically increases the contrast between different materials. Phase-separated structures in a poly (3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) blend that are impossible to observe using conventional STEM are clearly visualized. Furthermore, annealing behavior of the phase-separated structures is directly observed. The morphological transformations in the samples are consistent with their physical parameters, including their glass transition and melting temperatures. Our results indicate that electrostatic potential imaging is highly effective for observing organic materials.
Collapse
Affiliation(s)
- Shin Inamoto
- Morphological Research Laboratory, Toray Research Center, Inc., 3-7, Sonoyama 3-chome, Otsu, Shiga 520-8567, Japan
| | - Satoru Shimomura
- Advanced Materials Research Laboratories, Toray Industries, Inc., 2-1, Sonoyama 3-chome, Otsu, Shiga 520-0842, Japan
| | - Yuji Otsuka
- Morphological Research Laboratory, Toray Research Center, Inc., 3-7, Sonoyama 3-chome, Otsu, Shiga 520-8567, Japan
| |
Collapse
|
14
|
Sánchez-Santolino G, Lugg NR, Seki T, Ishikawa R, Findlay SD, Kohno Y, Kanitani Y, Tanaka S, Tomiya S, Ikuhara Y, Shibata N. Probing the Internal Atomic Charge Density Distributions in Real Space. ACS Nano 2018; 12:8875-8881. [PMID: 30074756 DOI: 10.1021/acsnano.8b03712] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Probing the charge density distributions in materials at atomic scale remains an extremely demanding task, particularly in real space. However, recent advances in differential phase contrast-scanning transmission electron microscopy (DPC-STEM) bring this possibility closer by directly visualizing the atomic electric field. DPC-STEM at atomic resolutions measures how a sub-angstrom electron probe passing through a material is affected by the atomic electric field, the field between the nucleus and the surrounding electrons. Here, we perform a fully quantitative analysis which allows us to probe the charge density distributions inside atoms, including both the positive nuclear and the screening electronic charges, with subatomic resolution and in real space. By combining state-of-the-art DPC-STEM experiments with advanced electron scattering simulations we are able to map the spatial distribution of the electron cloud within individual atomic columns. This work constitutes a crucial step toward the direct atomic scale determination of the local charge redistributions and modulations taking place in materials systems.
Collapse
Affiliation(s)
- Gabriel Sánchez-Santolino
- Institute of Engineering Innovation, School of Engineering , The University of Tokyo , 2-11-16 Yayoi , Bunkyo-ku, Tokyo 113-8656 , Japan
| | - Nathan R Lugg
- Institute of Engineering Innovation, School of Engineering , The University of Tokyo , 2-11-16 Yayoi , Bunkyo-ku, Tokyo 113-8656 , Japan
| | - Takehito Seki
- Institute of Engineering Innovation, School of Engineering , The University of Tokyo , 2-11-16 Yayoi , Bunkyo-ku, Tokyo 113-8656 , Japan
| | - Ryo Ishikawa
- Institute of Engineering Innovation, School of Engineering , The University of Tokyo , 2-11-16 Yayoi , Bunkyo-ku, Tokyo 113-8656 , Japan
| | - Scott D Findlay
- School of Physics and Astronomy , Monash University , Clayton , Victoria 3800 , Australia
| | - Yuji Kohno
- Electron Optics Division JEOL Limited, Tokyo 196-8558 , Japan
| | - Yuya Kanitani
- Advanced Technology Research Division, SONY Corporation, 4-14-1, Asahi , Atsugi-shi , Kanagawa 243-0014 , Japan
| | - Shinji Tanaka
- Advanced Technology Research Division, SONY Corporation, 4-14-1, Asahi , Atsugi-shi , Kanagawa 243-0014 , Japan
| | - Shigetaka Tomiya
- Advanced Technology Research Division, SONY Corporation, 4-14-1, Asahi , Atsugi-shi , Kanagawa 243-0014 , Japan
| | - Yuichi Ikuhara
- Institute of Engineering Innovation, School of Engineering , The University of Tokyo , 2-11-16 Yayoi , Bunkyo-ku, Tokyo 113-8656 , Japan
- Nanostructures Research Laboratory, Japan Fine Ceramic Center, 2-4-1 Mutsuno , Atsuta-ku, Nagoya 456-8587 , Japan
| | - Naoya Shibata
- Institute of Engineering Innovation, School of Engineering , The University of Tokyo , 2-11-16 Yayoi , Bunkyo-ku, Tokyo 113-8656 , Japan
- Nanostructures Research Laboratory, Japan Fine Ceramic Center, 2-4-1 Mutsuno , Atsuta-ku, Nagoya 456-8587 , Japan
| |
Collapse
|
15
|
Chen C, Li H, Seki T, Yin D, Sanchez-Santolino G, Inoue K, Shibata N, Ikuhara Y. Direct Determination of Atomic Structure and Magnetic Coupling of Magnetite Twin Boundaries. ACS Nano 2018; 12:2662-2668. [PMID: 29480718 DOI: 10.1021/acsnano.7b08802] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Clarifying how the atomic structure of interfaces/boundaries in materials affects the magnetic coupling nature across them is of significant academic value and will facilitate the development of state-of-the-art magnetic devices. Here, by combining atomic-resolution transmission electron microscopy, atomistic spin-polarized first-principles calculations, and differential phase contrast imaging, we conduct a systematic investigation of the atomic and electronic structures of individual Fe3O4 twin boundaries (TBs) and determine their concomitant magnetic couplings. We demonstrate that the magnetic coupling across the Fe3O4 TBs can be either antiferromagnetic or ferromagnetic, which directly depends on the TB atomic core structures and resultant electronic structures within a few atomic layers. Revealing the one-to-one correspondence between local atomic structures and magnetic properties of individual grain boundaries will shed light on in-depth understanding of many interesting magnetic behaviors of widely used polycrystalline magnetic materials, which will surely promote the development of advanced magnetic materials and devices.
Collapse
Affiliation(s)
- Chunlin Chen
- Shenyang National Laboratory for Materials Science , Institute of Metal Research, Chinese Academy of Sciences , Shenyang 110016 , China
- Advanced Institute for Materials Research , Tohoku University , 2-1-1 Katahira , Aoba-ku, Sendai 980-8577 , Japan
| | - Hongping Li
- Advanced Institute for Materials Research , Tohoku University , 2-1-1 Katahira , Aoba-ku, Sendai 980-8577 , Japan
- Institute for Advanced Materials, School of Materials Science and Engineering , Jiangsu University , Zhenjiang 212013 , China
| | - Takehito Seki
- Institute of Engineering Innovation , The University of Tokyo , 2-11-16 Yayoi , Bunkyo-ku, Tokyo 113-8656 , Japan
| | - Deqiang Yin
- Advanced Institute for Materials Research , Tohoku University , 2-1-1 Katahira , Aoba-ku, Sendai 980-8577 , Japan
- College of Aerospace Engineering , Chongqing University , Chongqing 400044 , China
| | - Gabriel Sanchez-Santolino
- Institute of Engineering Innovation , The University of Tokyo , 2-11-16 Yayoi , Bunkyo-ku, Tokyo 113-8656 , Japan
| | - Kazutoshi Inoue
- Advanced Institute for Materials Research , Tohoku University , 2-1-1 Katahira , Aoba-ku, Sendai 980-8577 , Japan
| | - Naoya Shibata
- Institute of Engineering Innovation , The University of Tokyo , 2-11-16 Yayoi , Bunkyo-ku, Tokyo 113-8656 , Japan
| | - Yuichi Ikuhara
- Advanced Institute for Materials Research , Tohoku University , 2-1-1 Katahira , Aoba-ku, Sendai 980-8577 , Japan
- Institute of Engineering Innovation , The University of Tokyo , 2-11-16 Yayoi , Bunkyo-ku, Tokyo 113-8656 , Japan
- Nanostructures Research Laboratory , Japan Fine Ceramics Center , 2-4-1 Mutsuno , Atsuta, Nagoya 456-8587 , Japan
| |
Collapse
|
16
|
Ishizuka A, Oka M, Seki T, Shibata N, Ishizuka K. Boundary-artifact-free determination of potential distribution from differential phase contrast signals. Microscopy (Oxf) 2017; 66:397-405. [PMID: 28992233 DOI: 10.1093/jmicro/dfx032] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 08/08/2017] [Indexed: 06/07/2023] Open
Abstract
The differential phase contrast (DPC) imaging in STEM was mainly used for a study of magnetic material in a medium resolution. An ideal DPC signals give the center of mass of the diffraction pattern, which is proportional to an electric field. Recently, the possibility of the DPC imaging at atomic resolution was demonstrated. Thus, the DPC imaging opens up the possibility to observe the object phase that is proportional to the electrostatic potential.In this report we investigate the numerical procedures to obtain the object phase from the two perpendicular DPC signals. Specifically, we demonstrate that the discrete cosine transform (DCT) is the method to solve the Poisson equation, since we can use the Neumann boundary condition directly specified by the DPC signals. Furthermore, based on the fast Fourier transform (FFT) of an extended DPC signal we introduce the scheme that gives an equivalent result that is obtained with the DCT. The results obtained with the DCT and extended FFT method are superior to the results obtained with commonly used FFT. In addition, we develop real-time integration schemes that update the result with the progress of the scan. Our real-time integration gives the reasonable result, and can be used in a view mode. We demonstrate that our numerical procedures work excellently with the experimental DPC signals obtained from SrTiO3 single crystal.
Collapse
Affiliation(s)
| | - Masaaki Oka
- HREM Research Inc., Higashimatsuyama 355-0055,Japan
| | - Takehito Seki
- Institute of Engineering Innovation, The University of Tokyo, Yayoi 2-11-16, Bunkyo, Japan
| | - Naoya Shibata
- Institute of Engineering Innovation, The University of Tokyo, Yayoi 2-11-16, Bunkyo, Japan
| | | |
Collapse
|
17
|
O'Brien K, Zhao M, Nolte D. Height Resolution of Antibody Spots Measured by Spinning-Disk Interferometry on the BioCD. Micromachines (Basel) 2016; 7:mi7020031. [PMID: 30407404 PMCID: PMC6190026 DOI: 10.3390/mi7020031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 01/20/2016] [Accepted: 02/04/2016] [Indexed: 06/08/2023]
Abstract
Spinning-disc interferometry (SDI) is a high-speed laser scanning approach to surface metrology that uses common-path interferometry to measure protein spots on a BioCD disk. The measurement sensitivity depends on the scanning pitch and on the time-base. Based on high-resolution laser scanning images of printed antibody spots, we quantify the protein sensitivity as a function of the scan parameters. For smoothly printed antibody spots scanned with a transverse spatial resolution of 1 μm, the surface height precision for a single 100 μm diameter protein spot is approximately 1 pm. This detection sensitivity sets the fundamental limit of detection for label-free BioCD biosensors performing immunoassays.
Collapse
Affiliation(s)
- Kevin O'Brien
- Department of Physics, University of California Berkeley, Berkeley, CA 94720-7300, USA.
| | - Ming Zhao
- Department of Physics, Purdue University, West Lafayette, IN 47907, USA.
| | - David Nolte
- Department of Physics, Purdue University, West Lafayette, IN 47907, USA.
| |
Collapse
|
18
|
Matsumoto T, So YG, Kohno Y, Sawada H, Ikuhara Y, Shibata N. Direct observation of Σ7 domain boundary core structure in magnetic skyrmion lattice. Sci Adv 2016; 2:e1501280. [PMID: 26933690 PMCID: PMC4758740 DOI: 10.1126/sciadv.1501280] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 12/02/2015] [Indexed: 05/15/2023]
Abstract
Skyrmions are topologically protected nanoscale magnetic spin entities in helical magnets. They behave like particles and tend to form hexagonal close-packed lattices, like atoms, as their stable structure. Domain boundaries in skyrmion lattices are considered to be important as they affect the dynamic properties of magnetic skyrmions. However, little is known about the fine structure of such skyrmion domain boundaries. We use differential phase contrast scanning transmission electron microscopy to directly visualize skyrmion domain boundaries in FeGe1-x Si x induced by the influence of an "edge" of a crystal grain. Similar to hexagonal close-packed atomic lattices, we find the formation of skyrmion "Σ7" domain boundary, whose orientation relationship is predicted by the coincidence site lattice theory to be geometrically stable. On the contrary, the skyrmion domain boundary core structure shows a very different structure relaxation mode. Individual skyrmions can flexibly change their size and shape to accommodate local coordination changes and free volumes formed at the domain boundary cores. Although atomic rearrangement is a common structural relaxation mode in crystalline grain boundaries, skyrmions show very unique and thus different responses to such local lattice disorders.
Collapse
Affiliation(s)
- Takao Matsumoto
- Institute of Engineering Innovation, School of Engineering, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656, Japan
- Corresponding author. E-mail:
| | - Yeong-Gi So
- Department of Materials Science and Engineering, Graduate School of Engineering and Resource Science, Akita University, 1-1 Tegata Gakuen-machi, Akita, Akita 010-8502, Japan
| | - Yuji Kohno
- JEOL Ltd., 1-2, Musashino 3-chome, Akishima, Tokyo 196-8558, Japan
| | - Hidetaka Sawada
- JEOL Ltd., 1-2, Musashino 3-chome, Akishima, Tokyo 196-8558, Japan
| | - Yuichi Ikuhara
- Institute of Engineering Innovation, School of Engineering, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Naoya Shibata
- Institute of Engineering Innovation, School of Engineering, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656, Japan
| |
Collapse
|
19
|
Albertin F, Astolfo A, Stampanoni M, Peccenini E, Hwu Y, Kaplan F, Margaritondo G. Ancient administrative handwritten documents: X-ray analysis and imaging. J Synchrotron Radiat 2015; 22:446-451. [PMID: 25723946 PMCID: PMC4786057 DOI: 10.1107/s1600577515000314] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Accepted: 01/07/2015] [Indexed: 06/04/2023]
Abstract
Handwritten characters in administrative antique documents from three centuries have been detected using different synchrotron X-ray imaging techniques. Heavy elements in ancient inks, present even for everyday administrative manuscripts as shown by X-ray fluorescence spectra, produce attenuation contrast. In most cases the image quality is good enough for tomography reconstruction in view of future applications to virtual page-by-page `reading'. When attenuation is too low, differential phase contrast imaging can reveal the characters from refractive index effects. The results are potentially important for new information harvesting strategies, for example from the huge Archivio di Stato collection, objective of the Venice Time Machine project.
Collapse
Affiliation(s)
- F. Albertin
- Faculté des Sciences de Base, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - A. Astolfo
- Swiss Light Source, Paul Scherrer Institut (PSI), Villigen, Switzerland
| | - M. Stampanoni
- Swiss Light Source, Paul Scherrer Institut (PSI), Villigen, Switzerland
- Institute for Biomedical Engineering, ETHZ, Zürich, Switzerland
| | - Eva Peccenini
- Department of Physics and Earth Sciences, University of Ferrara, Italy
- Laboratory TekneHub, Technopole of Ferrara, Italy
| | - Y. Hwu
- Institute of Physics, Academia Sinica, Taipei, Taiwan
| | - F. Kaplan
- Laboratoire d’Humanités Digitales, Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland
| | - G. Margaritondo
- Faculté des Sciences de Base, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| |
Collapse
|
20
|
Munro PRT, Endrizzi M, Diemoz PC, Hagen CK, Szafraniec MB, Millard TP, Zapata CE, Speller RD, Olivo A. Medicine, material science and security: the versatility of the coded-aperture approach. Philos Trans A Math Phys Eng Sci 2014; 372:20130029. [PMID: 24470413 PMCID: PMC3900034 DOI: 10.1098/rsta.2013.0029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The principal limitation to the widespread deployment of X-ray phase imaging in a variety of applications is probably versatility. A versatile X-ray phase imaging system must be able to work with polychromatic and non-microfocus sources (for example, those currently used in medical and industrial applications), have physical dimensions sufficiently large to accommodate samples of interest, be insensitive to environmental disturbances (such as vibrations and temperature variations), require only simple system set-up and maintenance, and be able to perform quantitative imaging. The coded-aperture technique, based upon the edge illumination principle, satisfies each of these criteria. To date, we have applied the technique to mammography, materials science, small-animal imaging, non-destructive testing and security. In this paper, we outline the theory of coded-aperture phase imaging and show an example of how the technique may be applied to imaging samples with a practically important scale.
Collapse
Affiliation(s)
- P. R. T. Munro
- Optical and Biomedical Engineering Laboratory, School of Electrical, Electronic and Computer Engineering, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
- Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - M. Endrizzi
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
| | - P. C. Diemoz
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
| | - C. K. Hagen
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
| | - M. B. Szafraniec
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
| | - T. P. Millard
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
| | - C. E. Zapata
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
| | - R. D. Speller
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
| | - A. Olivo
- Department of Medical Physics and Bioengineering, University College London, Malet Place, Gower St., London WC1E 6BT, UK
| |
Collapse
|
21
|
Hong YP, Gleber SC, O’Halloran TV, Que EL, Bleher R, Vogt S, Woodruff TK, Jacobsen C. Alignment of low-dose X-ray fluorescence tomography images using differential phase contrast. J Synchrotron Radiat 2014; 21:229-34. [PMID: 24365941 PMCID: PMC3874022 DOI: 10.1107/s1600577513029512] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 10/25/2013] [Indexed: 05/09/2023]
Abstract
X-ray fluorescence nanotomography provides unprecedented sensitivity for studies of trace metal distributions in whole biological cells. Dose fractionation, in which one acquires very low dose individual projections and then obtains high statistics reconstructions as signal from a voxel is brought together (Hegerl & Hoppe, 1976), requires accurate alignment of these individual projections so as to correct for rotation stage runout. It is shown here that differential phase contrast at 10.2 keV beam energy offers the potential for accurate cross-correlation alignment of successive projections, by demonstrating that successive low dose, 3 ms per pixel, images acquired at the same specimen position and rotation angle have a narrower and smoother cross-correlation function (1.5 pixels FWHM at 300 nm pixel size) than that obtained from zinc fluorescence images (25 pixels FWHM). The differential phase contrast alignment resolution is thus well below the 700 nm × 500 nm beam spot size used in this demonstration, so that dose fractionation should be possible for reduced-dose, more rapidly acquired, fluorescence nanotomography experiments.
Collapse
Affiliation(s)
- Young Pyo Hong
- Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
- Correspondence e-mail:
| | - Sophie-Charlotte Gleber
- Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA
| | - Thomas V. O’Halloran
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Emily L. Que
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - Reiner Bleher
- Department of Materials Science and Engineering, 2220 Campus Drive, Evanston, IL 60208, USA
| | - Stefan Vogt
- Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA
| | - Teresa K. Woodruff
- Department of Obstetrics and Gynecology, Northwestern University, 303 East Superior Street, Chicago, IL 60611, USA
| | - Chris Jacobsen
- Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
- Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439, USA
| |
Collapse
|
22
|
Takeuchi A, Uesugi K, Suzuki Y. Three-dimensional phase-contrast X-ray microtomography with scanning-imaging X-ray microscope optics. J Synchrotron Radiat 2013; 20:793-800. [PMID: 23955044 PMCID: PMC4032070 DOI: 10.1107/s0909049513018876] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Accepted: 07/08/2013] [Indexed: 05/30/2023]
Abstract
A three-dimensional (3D) X-ray tomographic micro-imaging system has been developed. The optical system is based on a scanning-imaging X-ray microscope (SIXM) optics, which is a hybrid system consisting of a scanning microscope optics with a one-dimensional (1D) focusing (line-focusing) device and an imaging microscope optics with a 1D objective. In the SIXM system, each 1D dataset of a two-dimensional (2D) image is recorded independently. An object is illuminated with a line-focused beam. Positional information of the region illuminated by the line-focused beam is recorded with the 1D imaging microscope optics as line-profile data. By scanning the object with the line focus, 2D image data are obtained. In the same manner as for a scanning microscope optics with a multi-pixel detector, imaging modes such as phase contrast and absorption contrast can be arbitrarily configured after the image data acquisition. By combining a tomographic scan method and the SIXM system, quantitative 3D imaging is performed. Results of a feasibility study of the SIXM for 3D imaging are shown.
Collapse
Affiliation(s)
- Akihisa Takeuchi
- Research and Utilization Division, Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Sayo-gun, Hyogo 679-5198, Japan.
| | | | | |
Collapse
|
23
|
Medjoubi K, Leclercq N, Langlois F, Buteau A, Lé S, Poirier S, Mercère P, Sforna MC, Kewish CM, Somogyi A. Development of fast, simultaneous and multi-technique scanning hard X-ray microscopy at Synchrotron Soleil. J Synchrotron Radiat 2013; 20:293-299. [PMID: 23412486 DOI: 10.1107/s0909049512052119] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 12/31/2012] [Indexed: 06/01/2023]
Abstract
A distributed fast-acquisition system for synchronized multi-technique experiments is presented, in which the collection of metadata and the asynchronous merging of large data volumes from multiple detectors are managed as part of the data collection process. This fast continuous scanning scheme, named FLYSCAN, enables measurement of microscopy data on a timescale of milliseconds per pixel. Proof-of-principle multi-technique experiments, namely scanning X-ray fluorescence spectrometry combined with absorption, differential phase contrast and dark-field imaging, have been performed on biological and geological samples.
Collapse
Affiliation(s)
- Kadda Medjoubi
- Synchrotron Soleil, Saint-Aubin, Gif sur Yvette, France.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Hornberger B, de Jonge MD, Feser M, Holl P, Holzner C, Jacobsen C, Legnini D, Paterson D, Rehak P, Strüder L, Vogt S. Differential phase contrast with a segmented detector in a scanning X-ray microprobe. J Synchrotron Radiat 2008; 15:355-62. [PMID: 18552427 PMCID: PMC3089014 DOI: 10.1107/s0909049508008509] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2008] [Accepted: 03/29/2008] [Indexed: 05/09/2023]
Abstract
Scanning X-ray microprobes are unique tools for the nanoscale investigation of specimens from the life, environmental, materials and other fields of sciences. Typically they utilize absorption and fluorescence as contrast mechanisms. Phase contrast is a complementary technique that can provide strong contrast with reduced radiation dose for weakly absorbing structures in the multi-keV range. In this paper the development of a segmented charge-integrating silicon detector which provides simultaneous absorption and differential phase contrast is reported. The detector can be used together with a fluorescence detector for the simultaneous acquisition of transmission and fluorescence data. It can be used over a wide range of photon energies, photon rates and exposure times at third-generation synchrotron radiation sources, and is currently operating at two beamlines at the Advanced Photon Source. Images obtained at around 2 keV and 10 keV demonstrate the superiority of phase contrast over absorption for specimens composed of light elements.
Collapse
Affiliation(s)
- B Hornberger
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
de Jonge MD, Vogt S, Legnini D, McNulty I, Rau C, Paterson D, Hornberger B, Holzner C, Jacobsen C. A method for phase reconstruction from measurements obtained using a configured detector with a scanning transmission X-ray microscope. Nucl Instrum Methods Phys Res A 2007; 582:218-220. [PMID: 18843383 PMCID: PMC2562734 DOI: 10.1016/j.nima.2007.08.111] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
We developed a technique for performing quantitative phase reconstructions from differential phase contrast images obtained using a configured detector in a scanning transmission X-ray microscope geometry. The technique uses geometric optics to describe the interaction of the X-ray beam with the specimen, which allows interpretation of the measured intensities in terms of the derivative of the phase thickness. Integration of the resulting directional derivatives is performed using a Fourier integration technique. We demonstrate the approach by reconstructing simulated measurements of a 0.5-µm-diameter gold sphere at 7-keV photon energy.
Collapse
Affiliation(s)
- Martin D. de Jonge
- Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439-4856, USA
- Corresponding author. E-mail address: (M.D. de Jonge)
| | - Stefan Vogt
- Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439-4856, USA
| | - Daniel Legnini
- Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439-4856, USA
| | - Ian McNulty
- Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439-4856, USA
| | - Christoph Rau
- Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX 11 0DE, United Kingdom
| | - David Paterson
- Australian Synchrotron, 800 Blackburn Road, Clayton, Vic. 3168, Australia
| | - Benjamin Hornberger
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800, USA
| | - Christian Holzner
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800, USA
| | - Chris Jacobsen
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800, USA
| |
Collapse
|