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| Author | van den Bos, K.H.W.; Krause, F.F.; Béché, A.; Verbeeck, J.; Rosenauer, A.; Van Aert, S. | ||||
| Title | Locating light and heavy atomic column positions with picometer precision using ISTEM | Type | A1 Journal article | ||
| Year | 2016 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 172 | Issue | 172 | Pages | 75-81 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Recently, imaging scanning transmission electron microscopy (ISTEM) has been proposed as a promising new technique combining the advantages of conventional TEM (CTEM) and STEM [1]. The ability to visualize light and heavy elements together makes it a particularly interesting new, spatially incoherent imaging mode. Here, we evaluate this technique in term of precision with which atomic column locations can be measured. By using statistical parameter estimation theory, we will show that these locations can be accurately measured with a precision in the picometer range. Furthermore, a quantitative comparison is made with HAADF STEM imaging to investigate the advantages of ISTEM. | ||||
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| Language | Wos | 000390600200009 | Publication Date | 2016-10-09 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 8 | Open Access | |
| Notes | The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0368.15N, G.0369.15N), and by a Ph.D. grant to K.H.W. van den Bos. The research leading to these results has received funding from the Deutsche Forschungsgemeinschaft under Contract No. RO 2057/4-2 and the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2. We thank Prof. G. Koster from the University of Twente for kindly providing us with the PbTiO3 test sample. | Approved  |
Most recent IF: 2.843 | ||
| Call Number | EMAT @ emat @ c:irua:136109UA @ admin @ c:irua:136109 | Serial | 4288 | ||
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| Author | Gauquelin, N.; van den Bos, K.H.W.; Béché, A.; Krause, F.F.; Lobato, I.; Lazar, S.; Rosenauer, A.; Van Aert, S.; Verbeeck, J. | ||||
| Title | Determining oxygen relaxations at an interface: A comparative study between transmission electron microscopy techniques | Type | A1 Journal article | ||
| Year | 2017 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 181 | Issue | 181 | Pages | 178-190 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Nowadays, aberration corrected transmission electron microscopy (TEM) is a popular method to characterise nanomaterials at the atomic scale. Here, atomically resolved images of nanomaterials are acquired, where the contrast depends on the illumination, imaging and detector conditions of the microscope. Visualization of light elements is possible when using low angle annular dark field (LAADF) STEM, annular bright field (ABF) STEM, integrated differential phase contrast (iDPC) STEM, negative spherical aberration imaging (NCSI) and imaging STEM (ISTEM). In this work, images of a NdGaO3-La0.67Sr0.33MnO3 (NGO-LSMO) interface are quantitatively evaluated by using statistical parameter estimation theory. For imaging light elements, all techniques are providing reliable results, while the techniques based on interference contrast, NCSI and ISTEM, are less robust in terms of accuracy for extracting heavy column locations. In term of precision, sample drift and scan distortions mainly limits the STEM based techniques as compared to NCSI. Post processing techniques can, however, partially compensate for this. In order to provide an outlook to the future, simulated images of NGO, in which the unavoidable presence of Poisson noise is taken into account, are used to determine the ultimate precision. In this future counting noise limited scenario, NCSI and ISTEM imaging will provide more precise values as compared to the other techniques, which can be related to the mechanisms behind the image recording. | ||||
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| Language | Wos | 000411170800022 | Publication Date | 2017-06-03 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 34 | Open Access | OpenAccess |
| Notes | The authors acknowledge financial support from Flanders (FWO, Belgium) through project fundings (G.0044.13N, G.0374.13N, G.0368.15N, G.0369.15N), and by a Ph.D. grant to K.H.W.v.d.B. The Qu-Ant-EM microscope used for this study was partly funded by the Hercules fund from the Flemish Government. A.B. and N.G. acknowledge the EUROTAPES project (FP7-NMP.2011.2.2-1 Grant no.280432) which partly funded this study. N.G., A.B. and J.V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. The research leading to these results has received funding from the Deutsche Forschungsgemeinschaft under Contract No. RO 2057/4-2 and the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2. We thank Prof. G. Koster from the University of Twente for kindly providing us with the LSMO-NGO test sample. | Approved |
Most recent IF: 2.843 | ||
| Call Number | EMAT @ emat @ c:irua:144435UA @ admin @ c:irua:144435 | Serial | 4620 | ||
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| Author | Verbeeck, J.; Béché, A.; Müller-Caspary, K.; Guzzinati, G.; Luong, M.A.; Den Hertog, M. | ||||
| Title | Demonstration of a 2 × 2 programmable phase plate for electrons | Type | A1 Journal article | ||
| Year | 2018 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 190 | Issue | Pages | 58-65 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | First results on the experimental realisation of a 2 × 2 programmable phase plate for electrons are presented. The design consists of an array of electrostatic elements that influence the phase of electron waves passing through 4 separately controllable aperture holes. This functionality is demonstrated in a conventional transmission electron microscope operating at 300 kV and results are in very close agreement with theoretical predictions. The dynamic creation of a set of electron probes with different phase symmetry is demonstrated, thereby bringing adaptive optics in TEM one step closer to reality. The limitations of the current design and how to overcome these in the future are discussed. Simulations show how further evolved versions of the current proof of concept might open new and exciting application prospects for beam shaping and aberration correction. | ||||
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| Language | Wos | 000432868800007 | Publication Date | 2018-04-18 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 73 | Open Access | Not_Open_Access: Available from 19.04.2020 |
| Notes | J.V. and A.B. acknowledge funding from the Fund for Scientific Research Flanders FWO project G093417N and the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX and ERC proof of concept project DLV-789598 ADAPTEM. The Qu-Ant-EM microscope used in this work was partly funded by the Hercules fund from the Flemish Government. MdH acknowledges financial support from the ANRCOSMOS (ANR-12-JS10-0002). MdH and ML acknowledge funding from the Laboratoire d’excellence LANEF in Grenoble (ANR-10-LABX-51-01). | Approved |
Most recent IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:150459UA @ admin @ c:irua:150459 | Serial | 4920 | ||
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| Author | Müller-Caspary, K.; Krause, F.F.; Winkler, F.; Béché, A.; Verbeeck, J.; Van Aert, S.; Rosenauer, A. | ||||
| Title | Comparison of first moment STEM with conventional differential phase contrast and the dependence on electron dose | Type | A1 Journal article | ||
| Year | 2019 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 203 | Issue | 203 | Pages | 95-104 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | This study addresses the comparison of scanning transmission electron microscopy (STEM) measurements of momentum transfers using the first moment approach and the established method that uses segmented annular detectors. Using an ultrafast pixelated detector to acquire four-dimensional, momentum-resolved STEM signals, both the first moment calculation and the calculation of the differential phase contrast (DPC) signals are done for the same experimental data. In particular, we investigate the ability to correct the segment-based signal to yield a suitable approximation of the first moment for cases beyond the weak phase object approximation. It is found that the measurement of momentum transfers using segmented detectors can approach the first moment measurement as close as 0.13 h/nm in terms of a root mean square (rms) difference in 10 nm thick SrTiO3 for a detector with 16 segments. This amounts to 35% of the rms of the momentum transfers. In addition, we present a statistical analysis of the precision of first moment STEM as a function of dose. For typical experimental settings with recent hardware such as a Medipix3 Merlin camera attached to a probe-corrected STEM, we find that the precision of the measurement of momentum transfers stagnates above certain doses. This means that other instabilities such as specimen drift or scan noise have to be taken into account seriously for measurements that target, e.g., the detection of bonding effects in the charge density. | ||||
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| Language | Wos | 000465021000013 | Publication Date | 2018-12-30 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 25 | Open Access | OpenAccess |
| Notes | ; The direct electron detector (Medipix3 Merlin) was funded by the Hercules fund from the Flemish Government. K. Muller-Caspary acknowledges funding from the Initiative and Network Fund of the Helmholtz Association within the framework of the Helmholtz Young Investigator Group moreSTEM (VH-NG-1317) at Forschungszentrum Julich, Germany. F. F. Krause acknowledges funding from the Central Research Development Fund of the University of Bremen, Germany. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant Agreement No. 770887). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) and the Research Fund of the University of Antwerp. ; | Approved |
Most recent IF: 2.843 | ||
| Call Number | UA @ admin @ c:irua:160213 | Serial | 5242 | ||
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| Author | Vanrompay, H.; Skorikov, A.; Bladt, E.; Béché, A.; Freitag, B.; Verbeeck, J.; Bals, S. | ||||
| Title | Fast versus conventional HAADF-STEM tomography of nanoparticles: advantages and challenges | Type | A1 Journal article | ||
| Year | 2021 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 221 | Issue | Pages | 113191 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | HAADF-STEM tomography is a widely used experimental technique for analyzing nanometer-scale crystalline structures of a large variety of materials in three dimensions. Unfortunately, the acquisition of conventional HAADF-STEM tilt series can easily take up one hour or more, depending on the complexity of the experiment. It is therefore far from straightforward to investigate samples that do not withstand long acquisition or to acquire large amounts of tilt series during a single TEM experiment. The latter would lead to the ability to obtain statistically meaningful 3D data, or to perform in situ 3D characterizations with a much shorter time resolution. Various HAADF-STEM acquisition strategies have been proposed to accelerate the tomographic acquisition and reduce the required electron dose. These methods include tilting the holder continuously while acquiring a projection “movie” and a hybrid, incremental, methodology which combines the benefits of the conventional and continuous technique. However, until now an experimental evaluation has been lacking. In this paper, the different acquisition strategies will be experimentally compared in terms of speed, resolution and electron dose. This evaluation will be performed based on experimental tilt series acquired for various metallic nanoparticles with different shapes and sizes. We discuss the data processing involved with the fast HAADF-STEM tilt series and provide a general guideline when which acquisition strategy should be preferentially used. | ||||
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| Language | Wos | 000612539600003 | Publication Date | 2020-12-08 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 15 | Open Access | OpenAccess |
| Notes | We acknowledge Prof. Luis M. Liz-Marzán and co-workers of the Bionanoplasmonics Laboratory, CIC biomaGUNE, Spain for providing the Au@Ag nanoparticles, Prof. Sara. E. Skrabalak and co-workers of Indiana University, United States for the provision of the Au octopods and Prof. Teri W. Odom of Northwestern University, United States for the provision of the Au nanostars. H.V. acknowledges financial support by the Research Foundation Flanders (FWO grant 1S32617N). S.B acknowledges financial support by the Research Foundation Flanders (FWO grant G.0381.16N). This project received funding as well from the European Union’s Horizon 2020 research and innovation program under grant agreement No 731019 (EUSMI) and No 815128 (REALNANO). The authors acknowledge the entire EMAT technical staff for their support.; sygma | Approved |
Most recent IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:174551 | Serial | 6660 | ||
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| Author | Béché, A.; Rouvière, J.L.; Barnes, J.P.; Cooper, D. | ||||
| Title | Dark field electron holography for strain measurement | Type | A1 Journal article | ||
| Year | 2011 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 111 | Issue | 3 | Pages | 227-238 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Dark field electron holography is a new TEM-based technique for measuring strain with nanometer scale resolution. Here we present the procedure to align a transmission electron microscope and obtain dark field holograms as well as the theoretical background necessary to reconstruct strain maps from holograms. A series of experimental parameters such as biprism voltage, sample thickness, exposure time, tilt angle and choice of diffracted beam are then investigated on a silicon-germanium layer epitaxially embedded in a silicon matrix in order to obtain optimal dark field holograms over a large field of view with good spatial resolution and strain sensitivity. | ||||
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| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000288638200007 | Publication Date | 2010-12-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 31 | Open Access | |
| Notes | Approved |
Most recent IF: 2.843; 2011 IF: 2.471 | |||
| Call Number | UA @ lucian @ c:irua:136368 | Serial | 4496 | ||
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| Author | Verbeeck, J.; Béché, A.; van den Broek, W. | ||||
| Title | A holographic method to measure the source size broadening in STEM | Type | A1 Journal article | ||
| Year | 2012 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 120 | Issue | Pages | 35-40 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Source size broadening is an important resolution limiting effect in modern STEM experiments. Here, we propose an alternative method to measure the source size broadening making use of a holographic biprism to create interference patterns in an empty Ronchigram. This allows us to measure the exact shape of the source size broadening with a much better sampling than previously possible. We find that the shape of the demagnified source deviates considerably from a Gaussian profile that is often assumed. We fit the profile with a linear combination of a Gaussian and a bivariate Cauchy distribution showing that even though the full width at half maximum is similar to previously reported measurements, the tails of the profile are considerable wider. This is of fundamental importance for quantitative comparison of STEM simulations with experiments as these tails make the image contrast dependent on the interatomic distance, an effect that cannot be reproduced by a single Gaussian profile of fixed width alone. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000308082600005 | Publication Date | 2012-06-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 29 | Open Access | |
| Notes | This work was supported by funding from the European Research Council under the 7th Framework Program (FP7), ERC Grant no. 246791 COUNTATOMS and ERC Starting Grant 278510 VORTEX. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. W. Van den Broek acknowledges funding from the Condor project, a project under the supervision of the Embedded Systems Institute (ESI) and FEI. This project is partially supported by the Dutch Ministry of Economic Affairs under the BSIK program. ECASJO_; | Approved |
Most recent IF: 2.843; 2012 IF: 2.470 | ||
| Call Number | UA @ lucian @ c:irua:100466UA @ admin @ c:irua:100466 | Serial | 1483 | ||
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| Author | Verbeeck, J.; Tian, H.; Béché, A. | ||||
| Title | A new way of producing electron vortex probes for STEM | Type | A1 Journal article | ||
| Year | 2012 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 113 | Issue | Pages | 83-87 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | A spiral holographic aperture is used in the condensor plane of a scanning transmission electron microscope to produce a focussed electron vortex probe carrying a topological charge of either −1, 0 or +1. The spiral aperture design has a major advantage over the previously used forked aperture in that the three beams with topological charge m=−1, 0, and 1 are not side by side in the specimen plane, but rather on top of each other, focussed at different heights. This allows us to have only one selected beam in focus on the sample while the others contribute only to a background signal. In this paper we describe the working principle as well as first experimental results demonstrating atomic resolution HAADF STEM images obtained with electron vortex probes. These results pave the way for atomic resolution magnetic information when combined with electron energy loss spectroscopy. | ||||
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| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000300554400002 | Publication Date | 2011-10-31 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 62 | Open Access | |
| Notes | J.V. wants to thank Miles Padgett for suggesting this setup and pointing to the relevant optics literature. Peter Schattschneider is acknowledged for in depth discussions on related topics. J.V acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Grant no. 46791-COUN-TATOMS and ERC Starting Grant no. 278510 VORTEX. The Qu-Ant-EM microscope is partially funded by the Hercules fund of the Flemish Government. ECASJO_; | Approved |
Most recent IF: 2.843; 2012 IF: 2.470 | ||
| Call Number | UA @ lucian @ c:irua:93624UA @ admin @ c:irua:93624 | Serial | 2336 | ||
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| Author | Béché, A.; Rouviere, J.L.; Barnes, J.P.; Cooper, D. | ||||
| Title | Strain measurement at the nanoscale : comparison between convergent beam electron diffraction, nano-beam electron diffraction, high resolution imaging and dark field electron holography | Type | A1 Journal article | ||
| Year | 2013 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 131 | Issue | Pages | 10-23 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Convergent beam electron diffraction (CBED), nano-beam electron diffraction (NBED or NBD), high resolution imaging (HRTEM and HRSTEM) and dark field electron holography (DFEH or HoloDark) are five TEM based techniques able to quantitatively measure strain at the nanometer scale. In order to demonstrate the advantages and disadvantages of each technique, two samples composed of epitaxial silicon-germanium layers embedded in a silicon matrix have been investigated. The five techniques are then compared in terms of strain precision and accuracy, spatial resolution, field of view, mapping abilities and ease of performance and analysis. (C) 2013 Elsevier By. All rights reserved. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000322631200002 | Publication Date | 2013-04-06 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 73 | Open Access | |
| Notes | Approved |
Most recent IF: 2.843; 2013 IF: 2.745 | |||
| Call Number | UA @ lucian @ c:irua:109774 | Serial | 3171 | ||
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| Author | de Backer, A.; Martinez, G.T.; MacArthur, K.E.; Jones, L.; Béché, A.; Nellist, P.D.; Van Aert, S. | ||||
| Title | Dose limited reliability of quantitative annular dark field scanning transmission electron microscopy for nano-particle atom-counting | Type | A1 Journal article | ||
| Year | 2015 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 151 | Issue | 151 | Pages | 56-61 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Quantitative annular dark field scanning transmission electron microscopy (ADF STEM) has become a powerful technique to characterise nano-particles on an atomic scale. Because of their limited size and beam sensitivity, the atomic structure of such particles may become extremely challenging to determine. Therefore keeping the incoming electron dose to a minimum is important. However, this may reduce the reliability of quantitative ADF STEM which will here be demonstrated for nano-particle atom-counting. Based on experimental ADF STEM images of a real industrial catalyst, we discuss the limits for counting the number of atoms in a projected atomic column with single atom sensitivity. We diagnose these limits by combining a thorough statistical method and detailed image simulations. | ||||
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| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000351237800008 | Publication Date | 2014-12-03 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 29 | Open Access | |
| Notes | 312483 Esteem2; 278510 Vortex; Fwo G039311; G006410; G037413; esteem2ta; ECASJO; | Approved |
Most recent IF: 2.843; 2015 IF: 2.436 | ||
| Call Number | c:irua:123927 c:irua:123927 | Serial | 753 | ||
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| Author | Guzzinati, G.; Clark, L.; Béché, A.; Juchtmans, R.; Van Boxem, R.; Mazilu, M.; Verbeeck, J. | ||||
| Title | Prospects for versatile phase manipulation in the TEM : beyond aberration correction | Type | A1 Journal article | ||
| Year | 2015 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 151 | Issue | 151 | Pages | 85-93 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In this paper we explore the desirability of a transmission electron microscope in which the phase of the electron wave can be freely controlled. We discuss different existing methods to manipulate the phase of the electron wave and their limitations. We show how with the help of current techniques the electron wave can already be crafted into specific classes of waves each having their own peculiar properties. Assuming a versatile phase modulation device is feasible, we explore possible benefits and methods that could come into existence borrowing from light optics where the so-called spatial light modulators provide programmable phase plates for quite some time now. We demonstrate that a fully controllable phase plate building on Harald Rose׳s legacy in aberration correction and electron optics in general would open an exciting field of research and applications. | ||||
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| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000351237800012 | Publication Date | 2014-10-22 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 19 | Open Access | |
| Notes | 278510 Vortex; Fwo; 312483 Esteem2; esteem2jra2; esteem2jra3 ECASJO_; | Approved |
Most recent IF: 2.843; 2015 IF: 2.436 | ||
| Call Number | c:irua:121405 c:irua:121405UA @ admin @ c:irua:121405 | Serial | 2731 | ||
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| Author | Martinez, G.T.; Jones, L.; de Backer, A.; Béché, A.; Verbeeck, J.; Van Aert, S.; Nellist, P.D. | ||||
| Title | Quantitative STEM normalisation : the importance of the electron flux | Type | A1 Journal article | ||
| Year | 2015 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 159 | Issue | 159 | Pages | 46-58 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Annular dark-field (ADF) scanning transmission electron microscopy (STEM) has become widely used in quantitative studies based on the opportunity to directly compare experimental and simulated images. This comparison merely requires the experimental data to be normalised and expressed in units of fractional beam-current. However, inhomogeneities in the response of electron detectors can complicate this normalisation. The quantification procedure becomes both experiment and instrument specific, requiring new simulations for the particular response of each instrument's detector, and for every camera-length used. This not only impedes the comparison between different instruments and research groups, but can also be computationally very time consuming. Furthermore, not all image simulation methods allow for the inclusion of an inhomogeneous detector response. In this work, we propose an alternative method for normalising experimental data in order to compare these with simulations that consider a homogeneous detector response. To achieve this, we determine the electron flux distribution reaching the detector by means of a camera-length series or a so-called atomic column cross-section averaged convergent beam electron diffraction (XSACBED) pattern. The result is then used to determine the relative weighting of the detector response. Here we show that the results obtained by this new electron flux weighted (EFW) method are comparable to the currently used method, while considerably simplifying the needed simulation libraries. The proposed method also allows one to obtain a metric that describes the quality of the detector response in comparison with the ideal detector response. | ||||
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| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000366220000006 | Publication Date | 2015-08-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 27 | Open Access | |
| Notes | 246791 Countatoms; 278510 Vortex; 312483 Esteem2; Fwo G036815; G036915; G037413; G004413; esteem2ta ECASJO; | Approved |
Most recent IF: 2.843; 2015 IF: 2.436 | ||
| Call Number | c:irua:127293 c:irua:127293UA @ admin @ c:irua:127293 | Serial | 2762 | ||
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| Author | Clark, L.; Guzzinati, G.; Béché, A.; Lubk, A.; Verbeeck, J. | ||||
| Title | Symmetry-constrained electron vortex propagation | Type | A1 Journal article | ||
| Year | 2016 | Publication | Physical review A | Abbreviated Journal | Phys Rev A |
| Volume | 93 | Issue | 93 | Pages | 063840 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Electron vortex beams hold great promise for development in transmission electron microscopy but have yet to be widely adopted. This is partly due to the complex set of interactions that occur between a beam carrying orbital angular momentum (OAM) and a sample. Herein, the system is simplified to focus on the interaction between geometrical symmetries, OAM, and topology. We present multiple simulations alongside experimental data to study the behavior of a variety of electron vortex beams after interacting with apertures of different symmetries and investigate the effect on their OAM and vortex structure, both in the far field and under free-space propagation. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000378197200006 | Publication Date | 2016-06-23 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9926 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.925 | Times cited | 7 | Open Access | |
| Notes | L.C., A.B., G.G., and J.V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant No. 278510—VORTEX. J.V. and A.L. acknowledge financial support from the European Union through the 7th Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative (Reference No. 312483 ESTEEM2). The Qu-Ant-EM microscope was partly funded by the Hercules fund of the Flemish Government.; esteem2jra3; ECASJO; | Approved |
Most recent IF: 2.925 | ||
| Call Number | c:irua:134086 c:irua:134086 | Serial | 4090 | ||
| Permanent link to this record | |||||
| Author | Guzzinati, G.; Clark, L.; Béché, A.; Verbeeck, J. | ||||
| Title | Measuring the orbital angular momentum of electron beams | Type | A1 Journal article | ||
| Year | 2014 | Publication | Physical review : A : atomic, molecular and optical physics | Abbreviated Journal | Phys Rev A |
| Volume | 89 | Issue | Pages | 025803 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The recent demonstration of electron vortex beams has opened up the new possibility of studying orbital angular momentum (OAM) in the interaction between electron beams and matter. To this aim, methods to analyze the OAM of an electron beam are fundamentally important and a necessary next step. We demonstrate the measurement of electron beam OAM through a variety of techniques. The use of forked holographic masks, diffraction from geometric apertures, and diffraction from a knife edge and the application of an astigmatic lens are all experimentally demonstrated. The viability and limitations of each are discussed with supporting numerical simulations. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000332224100014 | Publication Date | 2014-02-13 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1050-2947;1094-1622; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.925 | Times cited | 42 | Open Access | |
| Notes | Vortex; FP7; Countatoms; ESTEEM2; esteem2jra3 ECASJO; | Approved |
Most recent IF: 2.925; 2014 IF: 2.808 | ||
| Call Number | UA @ lucian @ c:irua:114577UA @ admin @ c:irua:114577 | Serial | 1972 | ||
| Permanent link to this record | |||||
| Author | Clark, L.; Béché, A.; Guzzinati, G.; Verbeeck, J. | ||||
| Title | Quantitative measurement of orbital angular momentum in electron microscopy | Type | A1 Journal article | ||
| Year | 2014 | Publication | Physical review : A : atomic, molecular and optical physics | Abbreviated Journal | Phys Rev A |
| Volume | 89 | Issue | 5 | Pages | 053818 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Electron vortex beams have been predicted to enable atomic scale magnetic information measurement, via transfer of orbital angular momentum. Research so far has focused on developing production techniques and applications of these beams. However, methods to measure the outgoing orbital angular momentum distribution are also a crucial requirement towards this goal. Here, we use a method to obtain the orbital angular momentum decomposition of an electron beam, using a multipinhole interferometer. We demonstrate both its ability to accurately measure orbital angular momentum distribution, and its experimental limitations when used in a transmission electron microscope. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000335826300012 | Publication Date | 2014-05-13 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1050-2947;1094-1622; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.925 | Times cited | 23 | Open Access | |
| Notes | 7th Framework Program (FP7); ERC Starting Grant No. 278510- VORTEX 7th Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative (Reference No. 312483 ESTEEM2). 7th Framework Program (FP7), ERC Grant No. 246791- COUNTATOMS. SP – 053818-1; esteem2jra3 ECASJO; | Approved |
Most recent IF: 2.925; 2014 IF: 2.808 | ||
| Call Number | UA @ lucian @ c:irua:117093UA @ admin @ c:irua:117093 | Serial | 2758 | ||
| Permanent link to this record | |||||
| Author | Béché, A.; Van Boxem, R.; Van Tendeloo, G.; Verbeeck, J. | ||||
| Title | Magnetic monopole field exposed by electrons | Type | A1 Journal article | ||
| Year | 2014 | Publication | Nature physics | Abbreviated Journal | Nat Phys |
| Volume | 10 | Issue | 1 | Pages | 26-29 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The experimental search for magnetic monopole particles(1-3) has, so far, been in vain. Nevertheless, these elusive particles of magnetic charge have fuelled a rich field of theoretical study(4-10). Here, we created an approximation of a magnetic monopole in free space at the end of a long, nanoscopically thin magnetic needle(11). We experimentally demonstrate that the interaction of this approximate magnetic monopole field with a beam of electrons produces an electron vortex state, as theoretically predicted for a true magnetic monopole(3,11-18). This fundamental quantum mechanical scattering experiment is independent of the speed of the electrons and has consequences for all situations where electrons meet such monopole magnetic fields, as, for example, in solids. The set-up not only shows an attractive way to produce electron vortex states but also provides a unique insight into monopole fields and shows that electron vortices might well occur in unexplored solid-state physics situations. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000328940100012 | Publication Date | 2013-11-29 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1745-2473;1745-2481; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 22.806 | Times cited | 131 | Open Access | |
| Notes | Vortex; Countatoms; Fwo ECASJO_; | Approved |
Most recent IF: 22.806; 2014 IF: 20.147 | ||
| Call Number | UA @ lucian @ c:irua:113740UA @ admin @ c:irua:113740 | Serial | 1885 | ||
| Permanent link to this record | |||||
| Author | Béché, A.; Goris, B.; Freitag, B.; Verbeeck, J. | ||||
| Title | Development of a fast electromagnetic beam blanker for compressed sensing in scanning transmission electron microscopy | Type | A1 Journal article | ||
| Year | 2016 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
| Volume | 108 | Issue | 108 | Pages | 093103 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The concept of compressed sensing was recently proposed to significantly reduce the electron dose in scanning transmission electron microscopy (STEM) while still maintaining the main features in the image. Here, an experimental setup based on an electromagnetic beam blanker placed in the condenser plane of a STEM is proposed. The beam blanker deflects the beam with a random pattern, while the scanning coils are moving the beam in the usual scan pattern. Experimental images at both the medium scale and high resolution are acquired and reconstructed based on a discrete cosine algorithm. The obtained results confirm that compressed sensing is highly attractive to limit beam damage in experimental STEM even though some remaining artifacts need to be resolved. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000375329200043 | Publication Date | 2016-03-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-6951 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.411 | Times cited | 40 | Open Access | |
| Notes | A.B and J.V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant No. 278510 VORTEX and under a contract for an Integrated Infrastructure Initiative (Reference No. 312483 ESTEEM2), from the GOA project SOLARPAINT and the POC project I13/009 from the University of Antwerp. B.G. acknowledges the Research Foundation Flanders (FWO Vlaanderen) for a postdoctoral research grant. The QuAnTem microscope was partially funded by the Hercules Foundation. We thank Zhaoliang Liao from the Mesa+ laboratory at the University of Twente for the perovskite test sample.; esteem2jra3 ECASJO; | Approved |
Most recent IF: 3.411 | ||
| Call Number | c:irua:131895 c:irua:131895UA @ admin @ c:irua:131895 | Serial | 4023 | ||
| Permanent link to this record | |||||
| Author | Jannis, D.; Müller-Caspary, K.; Béché, A.; Oelsner, A.; Verbeeck, J. | ||||
| Title | Spectroscopic coincidence experiments in transmission electron microscopy | Type | A1 Journal article | ||
| Year | 2019 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
| Volume | 114 | Issue | 14 | Pages | 143101 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | We demonstrate the feasibility of coincidence measurements on a conventional transmission electron microscope, revealing the temporal correlation between electron energy loss spectroscopy (EELS) and energy dispersive X-ray (EDX) spectroscopy events. We make use of a delay line detector with ps-range time resolution attached to a modified EELS spectrometer. We demonstrate that coincidence between both events, related to the excitation and deexcitation of atoms in a crystal, provides added information not present in the individual EELS or EDX spectra. In particular, the method provides EELS with a significantly suppressed or even removed background, overcoming the many difficulties with conventional parametric background fitting as it uses no assumptions on the shape of the background, requires no user input and does not suffer from counting noise originating from the background signal. This is highly attractive, especially when low concentrations of elements need to be detected in a matrix of other elements. |
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| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000464450200022 | Publication Date | 2019-04-08 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-6951 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.411 | Times cited | 18 | Open Access | OpenAccess |
| Notes | Fonds Wetenschappelijk Onderzoek, G093417 ; Horizon 2020 Framework Programme, 823717 ESTEEM3 ; Helmholtz Association, VH-NG-1327 ; | Approved |
Most recent IF: 3.411 | ||
| Call Number | EMAT @ emat @UA @ admin @ c:irua:159155 | Serial | 5168 | ||
| Permanent link to this record | |||||
| Author | Guzzinati, G.; Ghielens, W.; Mahr, C.; Béché, A.; Rosenauer, A.; Calders, T.; Verbeeck, J. | ||||
| Title | Electron Bessel beam diffraction for precise and accurate nanoscale strain mapping | Type | A1 Journal article | ||
| Year | 2019 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
| Volume | 114 | Issue | 24 | Pages | 243501 |
| Keywords | A1 Journal article; ADReM Data Lab (ADReM); Electron microscopy for materials research (EMAT) | ||||
| Abstract | Strain has a strong effect on the properties of materials and the performance of electronic devices. Their ever shrinking size translates into a constant demand for accurate and precise measurement methods with a very high spatial resolution. In this regard, transmission electron microscopes are key instruments thanks to their ability to map strain with a subnanometer resolution. Here, we present a method to measure strain at the nanometer scale based on the diffraction of electron Bessel beams. We demonstrate that our method offers a strain sensitivity better than 2.5 × 10−4 and an accuracy of 1.5 × 10−3, competing with, or outperforming, the best existing methods with a simple and easy to use experimental setup. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000472599100019 | Publication Date | 2019-06-17 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-6951 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.411 | Times cited | 17 | Open Access | OpenAccess |
| Notes | Deutsche Forschungsgemeinschaft, RO2057/12-2 ; Fonds Wetenschappelijk Onderzoek, G.0934.17N ; | Approved |
Most recent IF: 3.411 | ||
| Call Number | EMAT @ emat @UA @ admin @ c:irua:160119 | Serial | 5181 | ||
| Permanent link to this record | |||||
| Author | Cooper, D.; Rouvière, J.-L.; Béché, A.; Kadkhodazadeh, S.; Semenova, E.S.; Dunin-Borkowsk, R. | ||||
| Title | Quantitative strain mapping of InAs/InP quantum dots with 1 nm spatial resolution using dark field electron holography | Type | A1 Journal article | ||
| Year | 2011 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
| Volume | 99 | Issue | Pages | 261911-261913 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The optical properties of semiconductor quantum dots are greatly influenced by their strain state. Dark field electron holography has been used to measure the strain in InAsquantum dotsgrown in InP with a spatial resolution of 1 nm. A strain value of 5.4% ± 0.1% has been determined which is consistent with both measurements made by geometrical phase analysis of high angle annular dark field scanning transmission electron microscopy images and with simulations. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
| Language | Wos | 000298638500027 | Publication Date | 2012-01-03 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-6951; 1077-3118 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.411 | Times cited | 26 | Open Access | |
| Notes | Approved |
Most recent IF: 3.411; 2011 IF: 3.844 | |||
| Call Number | UA @ lucian @ c:irua:136428 | Serial | 4507 | ||
| Permanent link to this record | |||||
| Author | Cooper, D.; Le Royer, C.; Béché, A.; Rouvière, J.-L. | ||||
| Title | Strain mapping for the silicon-on-insulator generation of semiconductor devices by high-angle annular dark field scanning electron transmission microscopy | Type | A1 Journal article | ||
| Year | 2012 | Publication | Applied Physics Letters | Abbreviated Journal | Appl Phys Lett |
| Volume | 100 | Issue | Pages | 233121 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The strain in pMOS p-type metal-oxide-semiconductor devicesgrown on silicon-on-insulator substrates has been measured by using the geometrical phase analysis of high angle annular dark field scanning electron microscopy. We show that by using the latest generations of electron microscopes, the strain can now be quantitatively measured with a large field of view, a spatial resolution as low as 1 nm with a sensitivity as good as 0.15%. This technique is extremely flexible, provides both structural and strain information, and can be applied to all types of nanoscale materials both quickly and easily. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
| Language | Wos | Publication Date | 2012-06-08 | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-6951; 1077-3118 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.411 | Times cited | Open Access | ||
| Notes | Approved |
Most recent IF: 3.411; 2012 IF: 3.794 | |||
| Call Number | UA @ lucian @ c:irua:136432 | Serial | 4509 | ||
| Permanent link to this record | |||||
| Author | Cooper, D.; Denneulin, T.; Barnes, J.-P.; Hartmann, J.-M.; Hutin, L.; Le Royer, C.; Béché, A.; Rouvière, J.-L. | ||||
| Title | Strain mapping with nm-scale resolution for the silicon-on-insulator generation of semiconductor devices by advanced electron microscopy | Type | A1 Journal article | ||
| Year | 2012 | Publication | Applied Physics Letters | Abbreviated Journal | Appl Phys Lett |
| Volume | 112 | Issue | Pages | 124505 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Strain engineering in the conduction channel is a cost effective method of boosting the performance in state-of-the-art semiconductor devices. However, given the small dimensions of these devices, it is difficult to quantitatively measure the strain with the required spatial resolution. Three different transmission electron microscopy techniques, high-angle annular dark field scanning transmission electron microscopy, dark field electron holography, and nanobeam electron diffraction have been applied to measure the strain in simple bulk and SOI calibration specimens. These techniques are then applied to different gate length SiGe SOI pFET devices in order to measure the strain in the conduction channel. For these devices, improved spatial resolution is required, and strain maps with spatial resolutions as good as 1 nm have been achieved. Finally, we discuss the relative advantages and disadvantages of using these three different techniques when used for strain measurement. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
| Language | Wos | 000312829400128 | Publication Date | 2012-12-19 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-6951; 1077-3118 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.411 | Times cited | 14 | Open Access | |
| Notes | Approved |
Most recent IF: 3.411; 2012 IF: 3.794 | |||
| Call Number | UA @ lucian @ c:irua:136433 | Serial | 4510 | ||
| Permanent link to this record | |||||
| Author | Jones, E.; Cooper, D.; Rouvière, J.-L.; Béché, A.; Azize, M.; Palacios, T.; Gradecak, S. | ||||
| Title | Towards rapid nanoscale measurement of strain in III-nitride heterostructures | Type | A1 Journal article | ||
| Year | 2013 | Publication | Applied Physics Letters | Abbreviated Journal | Appl Phys Lett |
| Volume | 103 | Issue | Pages | 231904 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | We report the structural and compositional nanoscale characterization of InAlN/GaN nanoribbon-structured high electron mobility transistors (HEMTs) through the use of geometric phase analysis (GPA) and nanobeam electron diffraction (NBED). The strain distribution in the HEMT layer is quantified and compared to the expected strain profile for the nominal structure predicted by finite element analysis (FEA). Using the experimental strain results, the actual structure is determined and used to modify the FEA model. The improved fit of the model demonstrates that GPA and NBED provide a powerful platform for routine and rapid characterization of strain in III-V semiconducting device systems leading to insights into device evolution during processing and future device optimization. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
| Language | Wos | 000328634900025 | Publication Date | 2013-12-03 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-6951; 1077-3118 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.411 | Times cited | 6 | Open Access | |
| Notes | Approved |
Most recent IF: 3.411; 2013 IF: 3.515 | |||
| Call Number | UA @ lucian @ c:irua:136443 | Serial | 4513 | ||
| Permanent link to this record | |||||
| Author | Rouvière, J.-L.; Béché, A.; Martin, Y.; Denneulin, T.; Cooper, D. | ||||
| Title | Improved strain precision with high spatial resolution using nanobeam precession electron diffraction | Type | A1 Journal article | ||
| Year | 2013 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
| Volume | 103 | Issue | Pages | 241913 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | NanoBeam Electron Diffraction is a simple and efficient technique to measure strain in nanostructures. Here, we show that improved results can be obtained by precessing the electron beam while maintaining a few nanometer probe size, i.e., by doing Nanobeam Precession Electron Diffraction (N-PED). The precession of the beam makes the diffraction spots more uniform and numerous, making N-PED more robust and precise. In N-PED, smaller probe size and better precision are achieved by having diffraction disks instead of diffraction dots. Precision in the strain measurement better than 2 × 10−4 is obtained with a probe size approaching 1 nm in diameter. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
| Language | Wos | 000328706500031 | Publication Date | 2013-12-14 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-6951; 1077-3118 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.411 | Times cited | 53 | Open Access | |
| Notes | Approved |
Most recent IF: 3.411; 2013 IF: 3.515 | |||
| Call Number | UA @ lucian @ c:irua:136442 | Serial | 4502 | ||
| Permanent link to this record | |||||
| Author | Li, K.; Béché, A.; Song, M.; Sha, G.; Lu, X.; Zhang, K.; Du, Y.; Ringer, S.P.; Schryvers, D. | ||||
| Title | Atomistic structure of Cu-containing \beta" precipitates in an Al-Mg-Si-Cu alloy | Type | A1 Journal article | ||
| Year | 2014 | Publication | Scripta materialia | Abbreviated Journal | Scripta Mater |
| Volume | 75 | Issue | Pages | 86-89 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The beta '' precipitates in a peak-aged Al-Mg-Si-Cu alloy were measured with an average composition of 28.6Al-38.7Mg-26.5Si-5.17Cu (at.%) using atom probe tomography. High-angle annular dark-field observations revealed that Cu incompletely substitutes for the Mg-1 and Si-3 columns, preferentially for one column in each pair of Si-3. Cu-free Si columns form a parallelogram-shaped network that constitutes the basis of subsequent precipitates in the system, with a = 0.37 nm, b = 0.38 nm, gamma = 113 degrees and c = 0.405 nm. (C) 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | 000331025200022 | Publication Date | 2013-12-07 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1359-6462; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.747 | Times cited | 22 | Open Access | |
| Notes | Approved |
Most recent IF: 3.747; 2014 IF: 3.224 | |||
| Call Number | UA @ lucian @ c:irua:115749 | Serial | 201 | ||
| Permanent link to this record | |||||
| Author | Savchenko, T.M.; Buzzi, M.; Howald, L.; Ruta, S.; Vijayakumar, J.; Timm, M.; Bracher, D.; Saha, S.; Derlet, P.M.; Béché, A.; Verbeeck, J.; Chantrell, R.W.; Vaz, C.A.F.; Nolting, F.; Kleibert, A. | ||||
| Title | Single femtosecond laser pulse excitation of individual cobalt nanoparticles | Type | A1 Journal article | ||
| Year | 2020 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 102 | Issue | 20 | Pages | 205418 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Laser-induced manipulation of magnetism at the nanoscale is a rapidly growing research topic with potential for applications in spintronics. In this work, we address the role of the scattering cross section, thermal effects, and laser fluence on the magnetic, structural, and chemical stability of individual magnetic nanoparticles excited by single femtosecond laser pulses. We find that the energy transfer from the fs laser pulse to the nanoparticles is limited by the Rayleigh scattering cross section, which in combination with the light absorption of the supporting substrate and protective layers determines the increase in the nanoparticle temperature. We investigate individual Co nanoparticles (8 to 20 nm in size) as a prototypical model system, using x-ray photoemission electron microscopy and scanning electron microscopy upon excitation with single femtosecond laser pulses of varying intensity and polarization. In agreement with calculations, we find no deterministic or stochastic reversal of the magnetization in the nanoparticles up to intensities where ultrafast demagnetization or all-optical switching is typically reported in thin films. Instead, at higher fluences, the laser pulse excitation leads to photo-chemical reactions of the nanoparticles with the protective layer, which results in an irreversible change in the magnetic properties. Based on our findings, we discuss the conditions required for achieving laser-induced switching in isolated nanomagnets. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000589602000005 | Publication Date | 2020-11-16 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9950 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 3.7 | Times cited | 1 | Open Access | OpenAccess |
| Notes | This work received funding by the Swiss National Foundation (SNF) (Grants No. 200021160186 and No. 2002153540), the Swiss Nanoscience Institute (SNI) (Grant No. SNI P1502), the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No. 737093 (FEMTOTERABYTE), and the COST Action CA17123 (MAGNETOFON). Part of this work was performed at the SIM beamline of the Swiss Light Source (SLS), Paul Scherrer Institut, Villigen, Switzerland. Part of the simulations were undertaken on the VIKING cluster, which is a high-performance compute facility provided by the University of York. We kindly acknowledge Anja Weber from PSI for preparation of substrates with marker structures. A.B. and Jo Verbeeck acknowledge funding through FWO Project No. G093417N (“Compressed sensing enabling low dose imaging in transmission electron microscopy”) from the Flanders Research Fund. Jo Verbeeck acknowledges funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 823717 – ESTEEM3. S.S. acknowledges ETH Zurich Post-Doctoral fellowship and Marie Curie actions for people COFUND program.; esteem3JRA; esteem3reported | Approved |
Most recent IF: 3.7; 2020 IF: 3.836 | ||
| Call Number | EMAT @ emat @c:irua:174273 | Serial | 6669 | ||
| Permanent link to this record | |||||
| Author | Kleibert, A.; Balan, A.; Yanes, R.; Derlet, P.M.; Vaz, C.A.F.; Timm, M.; Fraile Rodríguez, A.; Béché, A.; Verbeeck, J.; Dhaka, R.S.; Radovic, M.; Nowak, U.; Nolting, F. | ||||
| Title | Direct observation of enhanced magnetism in individual size- and shape-selected 3d transition metal nanoparticles | Type | A1 Journal article | ||
| Year | 2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 95 | Issue | 95 | Pages | 195404 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Magnetic nanoparticles are critical building blocks for future technologies ranging from nanomedicine to spintronics. Many related applications require nanoparticles with tailored magnetic properties. However, despite significant efforts undertaken towards this goal, a broad and poorly understood dispersion of magnetic properties is reported, even within monodisperse samples of the canonical ferromagnetic 3d transition metals. We address this issue by investigating the magnetism of a large number of size- and shape-selected, individual nanoparticles of Fe, Co, and Ni using a unique set of complementary characterization techniques. At room temperature, only superparamagnetic behavior is observed in our experiments for all Ni nanoparticles within the investigated sizes, which range from 8 to 20 nm. However, Fe and Co nanoparticles can exist in two distinct magnetic states at any size in this range: (i) a superparamagnetic state, as expected from the bulk and surface anisotropies known for the respective materials and as observed for Ni, and (ii) a state with unexpected stable magnetization at room temperature. This striking state is assigned to significant modifications of the magnetic properties arising from metastable lattice defects in the core of the nanoparticles, as concluded by calculations and atomic structural characterization. Also related with the structural defects, we find that the magnetic state of Fe and Co nanoparticles can be tuned by thermal treatment enabling one to tailor their magnetic properties for applications. This paper demonstrates the importance of complementary single particle investigations for a better understanding of nanoparticle magnetism and for full exploration of their potential for applications. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000400665300002 | Publication Date | 2017-05-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 21 | Open Access | OpenAccess |
| Notes | We thank A. Weber, R. Schelldorfer, and J. Krbanjevic (Paul Scherrer Institut) for technical assistance. This paper was supported by the Swiss Nanoscience Institute, University of Basel. A.F.R. acknowledges support from the MICIIN “Ramón y Cajal” Programme. A.B. and J.V. acknowledge funding from the European Union under the European Research Council (ERC) Starting Grant No. 278510 VORTEX and under a contract for Integrated Infrastructure Initiative ESTEEM2 No. 312483. R.Y. and U.N. thank the Deutsche Forschungsgemeinschaft for financial support via Sonderforschungsbereich 1214. Part of this work was performed at the Surface/Interface: Microscopy (SIM) beamline of the Swiss Light Source, Paul Scherrer Institut, Villigen, Switzerland. | Approved |
Most recent IF: 3.836 | ||
| Call Number | EMAT @ emat @ c:irua:143634UA @ admin @ c:irua:143634 | Serial | 4575 | ||
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| Author | Tan, H.; Egoavil, R.; Béché, A.; Martinez, G.T.; Van Aert, S.; Verbeeck, J.; Van Tendeloo, G.; Rotella, H.; Boullay, P.; Pautrat, A.; Prellier, W. | ||||
| Title | Mapping electronic reconstruction at the metal-insulator interface in LaVO3/SrVO3 heterostructures | Type | A1 Journal article | ||
| Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 88 | Issue | 15 | Pages | 155123-155126 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | A (LaVO3)6/(SrVO3)(3) superlattice is studied with a combination of sub-A resolved scanning transmission electron microscopy and monochromated electron energy-loss spectroscopy. The V oxidation state is mapped with atomic spatial resolution enabling us to investigate electronic reconstruction at the LaVO3/SrVO3 interfaces. Surprisingly, asymmetric charge distribution is found at adjacent chemically symmetric interfaces. The local structure is proposed and simulated with a double channeling calculation which agrees qualitatively with our experiment. We demonstrate that local strain asymmetry is the likely cause of the electronic asymmetry of the interfaces. The electronic reconstruction at the interfaces extends much further than the chemical composition, varying from 0.5 to 1.2 nm. This distance corresponds to the length of charge transfer previously found in the (LaVO3)./(SrVO3). metal/insulating and the (LaAlO3)./(SrTiO3). insulating/insulating interfaces. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000326087100003 | Publication Date | 2013-10-21 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 15 | Open Access | |
| Notes | Hercules; 246791 COUNTATOMS; 278510 VORTEX; 246102 IFOX; 312483 ESTEEM2; FWO; GOA XANES meets ELNES; esteem2jra3 ECASJO; | Approved |
Most recent IF: 3.836; 2013 IF: 3.664 | ||
| Call Number | UA @ lucian @ c:irua:112733UA @ admin @ c:irua:112733 | Serial | 1944 | ||
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| Author | Juchtmans, R.; Béché, A.; Abakumov, A.; Batuk, M.; Verbeeck, J. | ||||
| Title | Using electron vortex beams to determine chirality of crystals in transmission electron microscopy | Type | A1 Journal article | ||
| Year | 2015 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 91 | Issue | 91 | Pages | 094112 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | We investigate electron vortex beams elastically scattered on chiral crystals. After deriving a general expression for the scattering amplitude of a vortex electron, we study its diffraction on point scatterers arranged on a helix. We derive a relation between the handedness of the helix and the topological charge of the electron vortex on one hand and the symmetry of the higher-order Laue zones in the diffraction pattern on the other for kinematically and dynamically scattered electrons. We then extend this to atoms arranged on a helix as found in crystals which belong to chiral space groups and propose a method to determine the handedness of such crystals by looking at the symmetry of the diffraction pattern. In contrast to alternative methods, our technique does not require multiple scattering, which makes it possible to also investigate extremely thin samples in which multiple scattering is suppressed. In order to verify the model, elastic scattering simulations are performed, and an experimental demonstration on Mn2Sb2O7 is given in which we find the sample to belong to the right-handed variant of its enantiomorphic pair. This demonstrates the usefulness of electron vortex beams to reveal the chirality of crystals in a transmission electron microscope and provides the required theoretical basis for further developments in this field. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000352017000002 | Publication Date | 2015-03-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 54 | Open Access | |
| Notes | Fwo; 312483 Esteem2; 278510 Vortex; esteem2jra1; esteem2jra2 ECASJO_; | Approved |
Most recent IF: 3.836; 2015 IF: 3.736 | ||
| Call Number | c:irua:125512 c:irua:125512 | Serial | 3825 | ||
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| Author | Parastaev, A.; Muravev, V.; Osta, E.H.; Kimpel, T.F.; Simons, J.F.M.; van Hoof, A.J.F.; Uslamin, E.; Zhang, L.; Struijs, J.J.C.; Burueva, D.B.; Pokochueva, E.V.; Kovtunov, K.V.; Koptyug, I.V.; Villar-Garcia, I.J.; Escudero, C.; Altantzis, T.; Liu, P.; Béché, A.; Bals, S.; Kosinov, N.; Hensen, E.J.M. | ||||
| Title | Breaking structure sensitivity in CO2 hydrogenation by tuning metal–oxide interfaces in supported cobalt nanoparticles | Type | A1 Journal article | ||
| Year | 2022 | Publication | Nature Catalysis | Abbreviated Journal | Nat Catal |
| Volume | 5 | Issue | 11 | Pages | 1051-1060 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) | ||||
| Abstract | A high dispersion of the active metal phase of transition metals on oxide supports is important when designing efficient heterogeneous catalysts. Besides nanoparticles, clusters and even single metal atoms can be attractive for a wide range of reactions. However, many industrially relevant catalytic transformations suffer from structure sensitivity, where reducing the size of the metal particles below a certain size substantially lowers catalytic performance. A case in point is the low activity of small cobalt nanoparticles in the hydrogenation of CO and CO2. Here we show how engineering of catalytic sites at the metal–oxide interface in cerium oxide–zirconium dioxide (ceria–zirconia)-supported cobalt can overcome this structure sensitivity. Few-atom cobalt clusters dispersed on 3 nm cobalt(II)-oxide particles stabilized by ceria–zirconia yielded a highly active CO2 methanation catalyst with a specific activity higher than that of larger particles under the same conditions. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000884939300006 | Publication Date | 2022-11-17 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2520-1158 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 37.8 | Times cited | 32 | Open Access | OpenAccess |
| Notes | This research was supported by the Applied and Engineering Sciences division of the Netherlands Organization for Scientific Research through the Alliander (now Qirion) Perspective program on Plasma Conversion of CO2. We acknowledge Diamond Light Source for time on beamline B18 under proposal SP20715-1. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. S.B. acknowledges support from the European Research Council (ERC Consolidator Grant #815128 REALNANO) and T.A. acknowledges funding from the University of Antwerp Research fund (BOF). A.B. received funding from the European Union under grant agreement No 823717 – ESTEEM3. The authors acknowledge funding through the Hercules grant (FWO, University of Antwerp) I003218N “Infrastructure for imaging nanoscale processes in gas/vapour or liquid environments”. I.V.K., D.B.B., and E.V.P. acknowledge the Russian Ministry of Science and Higher Education (contract 075-15-2021-580) for financial support of parahydrogen-based studies. Experiments using synchrotron radiation XPS were performed at the CIRCE beamline at ALBA Synchrotron with the collaboration of ALBA staff. F. Oropeza Palacio and Rim C.J. van de Poll are acknowledged for the help with RPES measurements.; esteem3reported; esteem3jra | Approved |
Most recent IF: 37.8 | ||
| Call Number | EMAT @ emat @c:irua:192068 | Serial | 7230 | ||
| Permanent link to this record | |||||