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| Author | Van den Broek, W.; Reed, B.W.; Béché, A.; Velazco, A.; Verbeeck, J.; Koch, C.T. | ||||
| Title | Various compressed sensing setups evaluated against Shannon sampling under constraint of constant illumination | Type | A1 Journal article | ||
| Year | 2019 | Publication | IEEE transactions on computational imaging | Abbreviated Journal | |
| Volume | 5 | Issue | 3 | Pages  |
502-514 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Under the constraint of constant illumination, an information criterion is formulated for the Fisher information that compressed sensing measurements in optical and transmission electron microscopy contain about the underlying parameters. Since this approach requires prior knowledge of the signal's support in the sparse basis, we develop a heuristic quantity, the detective quantum efficiency (DQE), that tracks this information criterion well without this knowledge. In this paper, it is shown that for the investigated choice of sensing matrices, and in the absence of read-out noise, i.e., with only Poisson noise present, compressed sensing does not raise the amount of Fisher information in the recordings above that of Shannon sampling. Furthermore, enabled by the DQE's analytical tractability, the experimental designs are optimized by finding out the optimal fraction of on pixels as a function of dose and read-out noise. Finally, we introduce a regularization and demonstrate, through simulations and experiment, that it yields reconstructions attaining minimum mean squared error at experimental settings predicted by the DQE as optimal. | ||||
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| Language | Wos | 000480352600013 | Publication Date | 2019-01-24 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2333-9403 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.546 | Times cited | 7 | Open Access | |
| Notes | ; This work was supported by the Hercules fund from the Flemish Government (Qu-Ant-EM microscope used for the experimental data). The work of W. Van den Broek was supported by the DFG under Grant BR 5095/2-1 (Compressed sensing in ptychography and transmission electron microscopy). The work of A. Beche, A. Velazco, and J. Verbeeck was supported by the FWO under Grant G093417N (Compressed sensing enabling low dose imaging in transmission electron microscopy). The work of Christoph T. Koch was supported by the DFG under Grant CRC 951. The associate editor coordinating the review of this manuscript and approving it for publication was Dr. Chrysanthe Preza. ; | Approved | Most recent IF: NA | ||
| Call Number | UA @ admin @ c:irua:161792 | Serial | 5368 | ||
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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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| 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 | ||
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| Author | Becker, M.; Guzzinati, G.; Béché, A.; Verbeeck, J.; Batelaan, H. | ||||
| Title | Asymmetry and non-dispersivity in the Aharonov-Bohm effect | Type | A1 Journal article | ||
| Year | 2019 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
| Volume | 10 | Issue | 10 | Pages |
1700 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Decades ago, Aharonov and Bohm showed that electrons are affected by electromagnetic potentials in the absence of forces due to fields. Zeilinger's theorem describes this absence of classical force in quantum terms as the “dispersionless” nature of the Aharonov-Bohm effect. Shelankov predicted the presence of a quantum “force” for the same Aharonov-Bohm physical system as elucidated by Berry. Here, we report an experiment designed to test Shelankov's prediction and we provide a theoretical analysis that is intended to elucidate the relation between Shelankov's prediction and Zeilinger's theorem. The experiment consists of the Aharonov-Bohm physical system; free electrons pass a magnetized nanorod and far-field electron diffraction is observed. The diffraction pattern is asymmetric confirming one of Shelankov's predictions and giving indirect experimental evidence for the presence of a quantum “force”. Our theoretical analysis shows that Zeilinger's theorem and Shelankov's result are both special cases of one theorem. | ||||
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| Language | Wos | 000464338100011 | Publication Date | 2019-04-12 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.124 | Times cited | 12 | Open Access | OpenAccess |
| Notes | ; H.B. would like to thank Michael Berry for bringing the presence of a quantum “force” to our attention. A.B., G.G. and J.V. acknowledge support from the European Research Council under the 7th Framework Program (FP7) ERC Starting Grant 278510 VORTEX. G.G. acknowledges support from the Fonds Wetenschappelijk Onderzoek -Vlaanderen (FWO). M.B. and H.B. acknowledge support by the U.S. National Science Foundation under Grant No. 1602755. ; | Approved | Most recent IF: 12.124 | ||
| Call Number | UA @ admin @ c:irua:159341 | Serial | 5241 | ||
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| Author | Liu, P.; Arslan Irmak, E.; De Backer, A.; De wael, A.; Lobato, I.; Béché, A.; Van Aert, S.; Bals, S. | ||||
| Title | Three-dimensional atomic structure of supported Au nanoparticles at high temperature | Type | A1 Journal article | ||
| Year | 2021 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
| Volume | 13 | Issue | Pages |
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| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Au nanoparticles (NPs) deposited on CeO2 are extensively used as thermal catalysts since the morphology of the NPs is expected to be stable at elevated temperatures. Although it is well known that the activity of Au NPs depends on their size and surface structure, their three-dimensional (3D) structure at the atomic scale has not been completely characterized as a function of temperature. In this paper, we overcome the limitations of conventional electron tomography by combining atom counting applied to aberration-corrected scanning transmission electron microscopy images and molecular dynamics relaxation. In this manner, we are able to perform an atomic resolution 3D investigation of supported Au NPs. Our results enable us to characterize the 3D equilibrium structure of single NPs as a function of temperature. Moreover, the dynamic 3D structural evolution of the NPs at high temperatures, including surface layer jumping and crystalline transformations, has been studied. | ||||
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| Language | Wos | 000612999200029 | Publication Date | 2020-12-29 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2040-3364 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 7.367 | Times cited | 13 | Open Access | OpenAccess |
| Notes | This work was supported by the European Research Council (Grant 815128 REALNANO to SB, Grant 770887 PICOMETRICS to SVA, Grant 823717 ESTEEM3). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through grants to A. D. w. and A. D. B. and project funding G.0267.18N.; sygma; esteem3JRA; esteem3reported | Approved | Most recent IF: 7.367 | ||
| Call Number | EMAT @ emat @c:irua:174858 | Serial | 6665 | ||
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| Author | Esteban, D.A.; Vanrompay, H.; Skorikov, A.; Béché, A.; Verbeeck, J.; Freitag, B.; Bals, S. | ||||
| Title | Fast electron low dose tomography for beam sensitive materials | Type | A1 Journal article | ||
| Year | 2021 | Publication | Microscopy And Microanalysis | Abbreviated Journal | Microsc Microanal |
| Volume | 27 | Issue | S1 | Pages |
2116-2118 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | Publication Date | 2021-07-30 | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1431-9276 | ISBN | Additional Links | UA library record | |
| Impact Factor | 1.891 | Times cited | Open Access | OpenAccess | |
| Notes | Approved | Most recent IF: 1.891 | |||
| Call Number | EMAT @ emat @c:irua:183278 | Serial | 6813 | ||
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| Author | van Huis, M.A.; Figuerola, A.; Fang, C.; Béché, A.; Zandbergen, H.W.; Manna, L. | ||||
| Title | Letter Chemical transformation of Au-tipped CdS nanorods into AuS/Cd core/shell particles by electron beam irradiation | Type | A1 Journal article | ||
| Year | 2011 | Publication | Nano letters | Abbreviated Journal | Nano Lett |
| Volume | 11 | Issue | 11 | Pages |
4555-4561 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | We demonstrate that electron irradiation of colloidal CdS nanorods carrying Au domains causes their evolution into AuS/Cd core/shell nanoparticles as a result of a concurrent chemical and morphological transformation. The shrinkage of the CdS nanorods and the growth of the Cd shell around the Au tips are imaged in real time, while the displacement of S atoms from the CdS nanorod to the Au domains is evidenced by high-sensitivity energy-dispersive X-ray (EDX) spectroscopy. The various nanodomains display different susceptibility to the irradiation, which results in nanoconfigurations that are very different from those obtained after thermal annealing. Such physical manipulations of colloidal nanocrystals can be exploited as a tool to access novel nanocrystal heterostructures. | ||||
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| Publisher | Place of Publication | Washington | Editor | ||
| Language | Wos | 000296674700009 | Publication Date | 2011-10-13 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1530-6984;1530-6992; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.712 | Times cited | 25 | Open Access | |
| Notes | Approved | Most recent IF: 12.712; 2011 IF: 13.198 | |||
| Call Number | UA @ lucian @ c:irua:93710 | Serial | 1814 | ||
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| Author | Cooper, D.; de la Peña, F.; Béché, A.; Rouvière, J.-L.; Servanton, G.; Pantel, R.; Morin, P. | ||||
| Title | Field mapping with nanometer-scale resolution for the next generation of electronic devices | Type | A1 Journal article | ||
| Year | 2011 | Publication | Nano letters | Abbreviated Journal | Nano Lett |
| Volume | 11 | Issue | 11 | Pages |
4585-4590 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In order to improve the performance of todays nanoscaled semiconductor devices, characterization techniques that can provide information about the position and activity of dopant atoms and the strain fields are essential. Here we demonstrate that by using a modern transmission electron microscope it is possible to apply multiple techniques to advanced materials systems in order to provide information about the structure, fields, and composition with nanometer-scale resolution. Off-axis electron holography has been used to map the active dopant potentials in state-of-the-art semiconductor devices with 1 nm resolution. These dopant maps have been compared to electron energy loss spectroscopy maps that show the positions of the dopant atoms. The strain fields in the devices have been measured by both dark field electron holography and nanobeam electron diffraction. | ||||
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| Publisher | Place of Publication | Washington | Editor | ||
| Language | Wos | 000296674700014 | Publication Date | 2011-10-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1530-6984 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.712 | Times cited | 12 | Open Access | |
| Notes | Approved | Most recent IF: 12.712; 2011 IF: 13.198 | |||
| Call Number | UA @ lucian @ c:irua:136369 | Serial | 4499 | ||
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| Author | Mueller, K.; Krause, F.F.; Béché, A.; Schowalter, M.; Galioit, V.; Loeffler, S.; Verbeeck, J.; Zweck, J.; Schattschneider, P.; Rosenauer, A. | ||||
| Title | Atomic electric fields revealed by a quantum mechanical approach to electron picodiffraction | Type | A1 Journal article | ||
| Year | 2014 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
| Volume | 5 | Issue | Pages |
5653 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | By focusing electrons on probes with a diameter of 50 pm, aberration-corrected scanning transmission electron microscopy (STEM) is currently crossing the border to probing subatomic details. A major challenge is the measurement of atomic electric fields using differential phase contrast (DPC) microscopy, traditionally exploiting the concept of a field- induced shift of diffraction patterns. Here we present a simplified quantum theoretical interpretation of DPC. This enables us to calculate the momentum transferred to the STEM probe from diffracted intensities recorded on a pixel array instead of conventional segmented bright- field detectors. The methodical development yielding atomic electric field, charge and electron density is performed using simulations for binary GaN as an ideal model system. We then present a detailed experimental study of SrTiO3 yielding atomic electric fields, validated by comprehensive simulations. With this interpretation and upgraded instrumentation, STEM is capable of quantifying atomic electric fields and high-contrast imaging of light atoms. | ||||
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| Language | Wos | 000347227700003 | Publication Date | 2014-12-15 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2041-1723; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.124 | Times cited | 197 | Open Access | |
| Notes | 246791 COUNTATOMS; 278510 VORTEX; Hercules; 312483 ESTEEM2; esteem2ta; ECASJO; | Approved | Most recent IF: 12.124; 2014 IF: 11.470 | ||
| Call Number | UA @ lucian @ c:irua:122835UA @ admin @ c:irua:122835 | Serial | 166 | ||
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| Author | Wolf, D.; Rodriguez, L.A.; Béché, A.; Javon, E.; Serrano, L.; Magen, C.; Gatel, C.; Lubk, A.; Lichte, H.; Bals, S.; Van Tendeloo, G.; Fernández-Pacheco, A.; De Teresa, J.M.; Snoeck, E. | ||||
| Title | 3D Magnetic Induction Maps of Nanoscale Materials Revealed by Electron Holographic Tomography | Type | A1 Journal article | ||
| Year | 2015 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
| Volume | 27 | Issue | 27 | Pages |
6771-6778 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The investigation of three-dimensional (3D) ferromagnetic nanoscale materials constitutes one of the key research areas of the current magnetism roadmap, and carries great potential to impact areas such as data storage, sensing and biomagnetism. The properties of such nanostructures are closely connected with their 3D magnetic nanostructure, making their determination highly valuable. Up to now, quantitative 3D maps providing both the internal magnetic and electric configuration of the same specimen with high spatial resolution are missing. Here, we demonstrate the quantitative 3D reconstruction of the dominant axial component of the magnetic induction and electrostatic potential within a cobalt nanowire (NW) of 100 nm in diameter with spatial resolution below 10 nanometers by applying electron holographic tomography. The tomogram was obtained using a dedicated TEM sample holder for acquisition, in combination with advanced alignment and tomographic reconstruction routines. The powerful approach presented here is widely applicable to a broad range of 3D magnetic nanostructures and may trigger the progress of novel spintronic non-planar nanodevices. | ||||
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| Language | Wos | 000362920700037 | Publication Date | 2015-09-08 | |
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| ISSN | 0897-4756;1520-5002; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 9.466 | Times cited | 50 | Open Access | OpenAccess |
| Notes | This work was supported by the European Union under the Seventh Framework Program under a contract for an Inte-grated Infrastructure Initiative Reference 312483-ESTEEM2. S.B. and A.B. gratefully acknowledge funding by ERC Starting grants number 335078 COLOURATOMS and number 278510 VORTEX. AF-P acknowledges an EPSRC Early Career fellowship and support from the Winton Foundation. E.S., C.G. and L.A. R. acknowledge the French ANR program for support though the project EMMA.; esteem2jra4; ECASJO;; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); | Approved | Most recent IF: 9.466; 2015 IF: 8.354 | ||
| Call Number | c:irua:129180 c:irua:129180 c:irua:129180 | Serial | 3950 | ||
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| Author | Jannis, D.; Müller-Caspary, K.; Béché, A.; Verbeeck, J. | ||||
| Title | Coincidence Detection of EELS and EDX Spectral Events in the Electron Microscope | Type | A1 Journal article | ||
| Year | 2021 | Publication | Applied Sciences-Basel | Abbreviated Journal | Appl Sci-Basel |
| Volume | 11 | Issue | 19 | Pages |
9058 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Recent advances in the development of electron and X-ray detectors have opened up the possibility to detect single events from which its time of arrival can be determined with nanosecond resolution. This allows observing time correlations between electrons and X-rays in the transmission electron microscope. In this work, a novel setup is described which measures individual events using a silicon drift detector and digital pulse processor for the X-rays and a Timepix3 detector for the electrons. This setup enables recording time correlation between both event streams while at the same time preserving the complete conventional electron energy loss (EELS) and energy dispersive X-ray (EDX) signal. We show that the added coincidence information improves the sensitivity for detecting trace elements in a matrix as compared to conventional EELS and EDX. Furthermore, the method allows the determination of the collection efficiencies without the use of a reference sample and can subtract the background signal for EELS and EDX without any prior knowledge of the background shape and without pre-edge fitting region. We discuss limitations in time resolution arising due to specificities of the silicon drift detector and discuss ways to further improve this aspect. | ||||
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| Language | Wos | 000710160300001 | Publication Date | 2021-09-28 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2076-3417 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.679 | Times cited | 9 | Open Access | OpenAccess |
| Notes | Fonds Wetenschappelijk Onderzoek, G042920 ; Horizon 2020 Framework Programme, 101017720 ; Helmholtz-Fonds, VH-NG-1317 ; | Approved | Most recent IF: 1.679 | ||
| Call Number | EMAT @ emat @c:irua:183336 | Serial | 6821 | ||
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| Author | Egoavil, R.; Huehn, S.; Jungbauer, M.; Gauquelin, N.; Béché, A.; Van Tendeloo, G.; Verbeeck; Moshnyaga, V. | ||||
| Title | Phase problem in the B-site ordering of La2CoMnO6 : impact on structure and magnetism | Type | A1 Journal article | ||
| Year | 2015 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
| Volume | 7 | Issue | 7 | Pages |
9835-9843 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Epitaxial double perovskite La2CoMnO6 (LCMO) films were grown by metalorganic aerosol deposition on SrTiO3(111) substrates. A high Curie temperature, T-C = 226 K, and large magnetization close to saturation, M-S(5 K) = 5.8 mu(B)/f.u., indicate a 97% degree of B-site (Co,Mn) ordering within the film. The Co/Mn ordering was directly imaged at the atomic scale by scanning transmission electron microscopy with energy-dispersive X-ray spectroscopy (STEM-EDX). Local electron-energy-loss spectroscopy (EELS) measurements reveal that the B-sites are predominantly occupied by Co2+ and Mn4+ ions in quantitative agreement with magnetic data. Relatively small values of the (1/2 1/2 1/2) superstructure peak intensity, obtained by X-ray diffraction (XRD), point out the existence of ordered domains with an arbitrary phase relationship across the domain boundary. The size of these domains is estimated to be in the range 35-170 nm according to TEM observations and modelling the magnetization data. These observations provide important information towards the complexity of the cation ordering phenomenon and its implications on magnetism in double perovskites, and similar materials. | ||||
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| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos | 000354983100060 | Publication Date | 2015-05-05 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 2040-3364;2040-3372; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 7.367 | Times cited | 37 | Open Access | |
| Notes | 312483 ESTEEM2; FWO G004413N; 246102 IFOX; Hercules; esteem2_jra3 | Approved | Most recent IF: 7.367; 2015 IF: 7.394 | ||
| Call Number | c:irua:126423 c:irua:126423 | Serial | 2586 | ||
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| Author | De Backer, A.; De Wael, A.; Gonnissen, J.; Martinez, G.T.; Béché, A.; MacArthur, K.E.; Jones, L.; Nellist, P.D.; Van Aert, S. | ||||
| Title | Quantitative annular dark field scanning transmission electron microscopy for nanoparticle atom-counting: What are the limits? | Type | P1 Proceeding | ||
| Year | 2015 | Publication | Journal of physics : conference series | Abbreviated Journal | |
| Volume | 644 | Issue | 644 | Pages |
012034 |
| Keywords | P1 Proceeding; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Quantitative atomic resolution annular dark field scanning transmission electron microscopy (ADF STEM) has become a powerful technique for nanoparticle atom-counting. However, a lot of nanoparticles provide a severe characterisation challenge because of their limited size and beam sensitivity. Therefore, quantitative ADF STEM may greatly benefit from statistical detection theory in order to optimise the instrumental microscope settings such that the incoming electron dose can be kept as low as possible whilst still retaining single-atom precision. The principles of detection theory are used to quantify the probability of error for atom-counting. This enables us to decide between different image performance measures and to optimise the experimental detector settings for atom-counting in ADF STEM in an objective manner. To demonstrate this, ADF STEM imaging of an industrial catalyst has been conducted using the near-optimal detector settings. For this experiment, we discussed the limits for atom-counting diagnosed by combining a thorough statistical method and detailed image simulations. | ||||
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| Language | Wos | 000366826200034 | Publication Date | 2015-10-13 | |
| Series Editor | Series Title | Abbreviated Series Title | Electron Microscopy and Analysis Group Conference (EMAG), JUN 02-JUL 02, 2015, Manchester, ENGLAND | ||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1742-6588 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | Times cited | Open Access | |||
| Notes | The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project funding (G.0368.15N, G.0369.15N, and G.0374.15N) and a PhD research grant to A De Backer. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative-I3), ERC Starting Grant 278510 Vortex, and the UK Engineering and Physical Sciences Research Council (EP/K032518/1). The authors acknowledge Johnson-Matthey for providing the sample and PhD funding to K E MacArthur. A Rosenauer is acknowledged for providing the STEMsim program.; esteem2jra2; ECASJO; | Approved | Most recent IF: NA | ||
| Call Number | c:irua:130314 c:irua:130314 | Serial | 4050 | ||
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| Author | de Backer, A.; De wael, A.; Gonnissen, J.; Martinez, G.T.; Béché, A.; MacArthur, K.E.; Jones, L.; Nellist, P.D.; Van Aert, S. | ||||
| Title | Quantitative annular dark field scanning transmission electron microscopy for nanoparticle atom-counting : what are the limits? | Type | A1 Journal article | ||
| Year | 2015 | Publication | Journal of physics : conference series | Abbreviated Journal | |
| Volume | 644 | Issue | Pages |
012034-4 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Quantitative atomic resolution annular dark field scanning transmission electron microscopy (ADF STEM) has become a powerful technique for nanoparticle atom-counting. However, a lot of nanoparticles provide a severe characterisation challenge because of their limited size and beam sensitivity. Therefore, quantitative ADF STEM may greatly benefit from statistical detection theory in order to optimise the instrumental microscope settings such that the incoming electron dose can be kept as low as possible whilst still retaining single-atom precision. The principles of detection theory are used to quantify the probability of error for atom-counting. This enables us to decide between different image performance measures and to optimise the experimental detector settings for atom-counting in ADF STEM in an objective manner. To demonstrate this, ADF STEM imaging of an industrial catalyst has been conducted using the near-optimal detector settings. For this experiment, we discussed the limits for atomcounting diagnosed by combining a thorough statistical method and detailed image simulations. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Bristol | Editor | ||
| Language | Wos | Publication Date | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1742-6588; 1742-6596 | ISBN | Additional Links | UA library record | |
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ lucian @ c:irua:129198 | Serial | 4506 | ||
| Permanent link to this record | |||||
| Author | Idrissi, H.; Ghidelli, M.; Béché, A.; Turner, S.; Gravier, S.; Blandin, J.-J.; Raskin, J.-P.; Schryvers, D.; Pardoen, T. | ||||
| Title | Atomic-scale viscoplasticity mechanisms revealed in high ductility metallic glass films | Type | A1 Journal article | ||
| Year | 2019 | Publication | Scientific reports | Abbreviated Journal | Sci Rep-Uk |
| Volume | 9 | Issue | 1 | Pages |
13426 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The fundamental plasticity mechanisms in thin freestanding Zr65Ni35 metallic glass films are investigated in order to unravel the origin of an outstanding strength/ductility balance. The deformation process is homogenous until fracture with no evidence of catastrophic shear banding. The creep/relaxation behaviour of the films was characterized by on-chip tensile testing, revealing an activation volume in the range 100–200 Å3. Advanced high-resolution transmission electron microscopy imaging and spectroscopy exhibit a very fine glassy nanostructure with well-defined dense Ni-rich clusters embedded in Zr-rich clusters of lower atomic density and a ~2–3 nm characteristic length scale. Nanobeam electron diffraction analysis reveals that the accumulation of plastic deformation at roomtemperature correlates with monotonously increasing disruption of the local atomic order. These results provide experimental evidences of the dynamics of shear transformation zones activation in metallic glasses. The impact of the nanoscale structural heterogeneities on the mechanical properties including the rate dependent behaviour is discussed, shedding new light on the governing plasticity mechanisms in metallic glasses with initially heterogeneous atomic arrangement. |
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| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000486139700008 | Publication Date | 2019-09-17 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2045-2322 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.259 | Times cited | Open Access | ||
| Notes | H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). This work was supported by the FNRS under Grant PDR – T.0178.19. FWO project G093417N (‘Compressed sensing enabling low dose imaging in transmission electron microscopy’) and Hercules fund ‘Direct electron detector for soft matter TEM’ from Flemish Government are acknowledged. | Approved | Most recent IF: 4.259 | ||
| Call Number | EMAT @ emat @c:irua:162786 | Serial | 5375 | ||
| Permanent link to this record | |||||
| Author | Lepot, K.; Addad, A.; Knoll, A.H.; Wang, J.; Troadec, D.; Béché, A.; Javaux, E.J. | ||||
| Title | Iron minerals within specific microfossil morphospecies of the 1.88 Ga Gunflint Formation | Type | A1 Journal article | ||
| Year | 2017 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
| Volume | 8 | Issue | 8 | Pages |
14890 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Problematic microfossils dominate the palaeontological record between the Great Oxidation Event 2.4 billion years ago (Ga) and the last Palaeoproterozoic iron formations, deposited 500–600 million years later. These fossils are often associated with iron-rich sedimentary rocks, but their affinities, metabolism, and, hence, their contributions to Earth surface oxidation and Fe deposition remain unknown. Here we show that specific microfossil populations of the 1.88 Ga Gunflint Iron Formation contain Fe-silicate and Fe-carbonate nanocrystal concentrations in cell interiors. Fe minerals are absent in/on all organically preserved cell walls. These features are consistent with in vivo intracellular Fe biomineralization, with subsequent in situ recrystallization, but contrast with known patterns of post-mortem Fe mineralization. The Gunflint populations that display relatively large cells (thick-walled spheres, filament-forming rods) and intra-microfossil Fe minerals are consistent with oxygenic photosynthesizers but not with other Fe-mineralizing microorganisms studied so far. Fe biomineralization may have protected oxygenic photosynthesizers against Fe2+ toxicity during the Palaeoproterozoic. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000397129900001 | Publication Date | 2017-03-23 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.124 | Times cited | 20 | Open Access | OpenAccess |
| Notes | We thank J.-P. Cullus (thin sections), G. Spronck and C. Henrist (TEM), M. Cabié and C. Dominici (FIB), S. Bernard and C. Karunakaran (STXM), F. Bourdelle and G. Ji (EELS), P. Recourt (SEM). This study was co-funded by FRFC Grant no. 2.4558.09F (E.J.J.), CNRS-INSU (K.L.), FNRS (K.L.), ERC StG ELiTE Grant no. 308074 (E.J.J.), BELSPO IAP PLANET TOPERS (E.J.J.), NASA Astrobiology Institute (A.H.K.), Conseil Régional du Nord-Pas de Calais+European Regional Development Fund+CNRS-INSU (TEM in Lille), FP7-ESMI no. 262348 (TEM at EMAT Antwerp) and ANR-15-CE31-0003-01 (M6fossils, K.L.). We thank Noah Planavsky and two anonymous reviewers for thorough reviews that helped improve the paper. | Approved | Most recent IF: 12.124 | ||
| Call Number | EMAT @ emat @ c:irua:141919 | Serial | 4536 | ||
| Permanent link to this record | |||||
| Author | Guzzinati, G.; Béché, A.; Lourenço-Martins, H.; Martin, J.; Kociak, M.; Verbeeck, J. | ||||
| Title | Probing the symmetry of the potential of localized surface plasmon resonances with phase-shaped electron beams | Type | A1 Journal article | ||
| Year | 2017 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
| Volume | 8 | Issue | 8 | Pages |
14999 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Plasmonics, the science and technology of the interaction of light with metallic objects, is fundamentally changing the way we can detect, generate and manipulate light. Although the field is progressing swiftly, thanks to the availability of nanoscale manufacturing and analysis methods, fundamental properties such as the plasmonic excitations’ symmetries cannot be accessed directly, leading to a partial, sometimes incorrect, understanding of their properties. Here we overcome this limitation by deliberately shaping the wave function of an electron beam to match a plasmonic excitations’ symmetry in a modified transmission electron microscope. We show experimentally and theoretically that this offers selective detection of specific plasmon modes within metallic nanoparticles, while excluding modes with other symmetries. This method resembles the widespread use of polarized light for the selective excitation of plasmon modes with the advantage of locally probing the response of individual plasmonic objects and a far wider range of symmetry selection criteria. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000399084300001 | Publication Date | 2017-04-12 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.124 | Times cited | 84 | Open Access | OpenAccess |
| Notes | ; We thank F.J. Garcia de Abajo and D.M. Ugarte for interesting and fruitful discussion. This work was supported by funding from the European Research Council under the 7th Framework Program (FP7) ERC Starting Grant 278510 VORTEX. Financial support from the European Union under the Framework 7 program under a contract for an Integrated Infrastructure Initiative (Reference number 312483 ESTEEM2) is also gratefully acknowledged. Aluminum nanostructures were fabricated using the Nanomat nanofabrication facility. ; | Approved | Most recent IF: 12.124 | ||
| Call Number | EMAT @ emat @ c:irua:142205UA @ admin @ c:irua:142205 | Serial | 4548 | ||
| Permanent link to this record | |||||
| Author | Vanrompay, H.; Bladt, E.; Albrecht, W.; Béché, A.; Zakhozheva, M.; Sánchez-Iglesias, A.; Liz-Marzán, L.M.; Bals, S. | ||||
| Title | 3D characterization of heat-induced morphological changes of Au nanostars by fast in situ electron tomography | Type | A1 Journal article | ||
| Year | 2018 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
| Volume | 10 | Issue | 10 | Pages |
22792-22801 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | A thorough understanding of the thermal stability and potential reshaping of anisotropic gold nanostars is required for various potential applications. Combination of a tomographic heating holder with fast tilt series acquisition has been used to monitor temperature-induced morphological changes of Au nanostars. The outcome of our 3D investigations can be used as an input for boundary element method simulations, enabling us to investigate the influence of reshaping on the nanostars’ plasmonic properties. Our work leads to a better understanding of the mechanism behind thermal reshaping. In addition, the approach presented here is generic and can hence be applied to a wide variety of nanoparticles made of different materials and with arbitrary morphology. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000453248100010 | Publication Date | 2018-11-28 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2040-3364 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 7.367 | Times cited | 55 | Open Access | OpenAccess |
| Notes | H.V. acknowledges financial support by the Research Foundation Flanders (FWO grant 1S32617N). E.B. acknowledges a post-doctoral grant from the Research Foundation Flanders (FWO, Belgium). W.A. acknowledges an Individual Fellowship funded by the Marie Sklodowska-Curie Actions (MSCA) in Horizon 2020. The authors acknowledge funding from European Commission Grant (EUSMI 731019 to S.B., L.M.L.-M. and M.Z. and MUMMERING 765604 to S.B. and M.Z.). S.B. acknowledges financial support from European Research Council (ERC Starting Grant #335078- COLOURATOMS).; Ecas_sara | Approved | Most recent IF: 7.367 | ||
| Call Number | EMAT @ emat @c:irua:155718UA @ admin @ c:irua:155718 | Serial | 5071 | ||
| 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 | Bhat, S.G.; Gauquelin, N.; Sebastian, N.K.; Sil, A.; Béché, A.; Verbeeck, J.; Samal, D.; Kumar, P.S.A. | ||||
| Title | Orthorhombic vs. hexagonal epitaxial SrIrO3 thin films : structural stability and related electrical transport properties | Type | A1 Journal article | ||
| Year | 2018 | Publication | Europhysics letters | Abbreviated Journal | Epl-Europhys Lett |
| Volume | 122 | Issue | 2 | Pages |
28003 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Metastable orthorhombic SrIrO3 (SIO) is an arch-type spin-orbit coupled material. We demonstrate here a controlled growth of relatively thick (200 nm) SIO films that transform from bulk “6H-type” structure with monoclinic distortion to an orthorhombic lattice by controlling growth temperature. Extensive studies based on high-resolution X-ray diffraction and transmission electron microscopy infer a two distinct structural phases of SIO. Electrical transport reveals a weak temperature-dependent semi-metallic character for both phases. However, the temperature-dependent Hall-coefficient for the orthorhombic SIO exhibits a prominent sign change, suggesting a multiband character in the vicinity of E-F. Our findings thus unravel the subtle structure-property relation in SIO epitaxial thin films. Copyright (C) EPLA, 2018 | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Paris | Editor | ||
| Language | Wos | 000435517300001 | Publication Date | 2018-06-18 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0295-5075 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.957 | Times cited | 4 | Open Access | Not_Open_Access |
| Notes | ; SGB and DS acknowledge useful discussions with E. P. Houwman, University of Twente, on X-ray diffraction. DS would like to thank H. Takagi, Max-Planck Institute for Solid State Research, Stuttgart, for the fruitful discussion on the transport properties of SIO thin films. SGB and NKS thank A. Aravind, Bishop Moore College, Mavelikara, for his valuable inputs while depositing the thin films of SIO. SGB, NKS and PSAK acknowledge Nano Mission Council, Department of Science & Technology, India, for the funding. DS acknowledges the financial support from Max-Planck Society through MaxPlanck Partner Group. NG, AB and JV acknowledge funding from GOA project “Solarpaint” of the University of Antwerp and FWO project G093417N. ; | Approved | Most recent IF: 1.957 | ||
| Call Number | UA @ lucian @ c:irua:152074UA @ admin @ c:irua:152074 | Serial | 5034 | ||
| Permanent link to this record | |||||
| Author | Prabhakara, V.; Jannis, D.; Béché, A.; Bender, H.; Verbeeck, J. | ||||
| Title | Strain measurement in semiconductor FinFET devices using a novel moiré demodulation technique | Type | A1 Journal article | ||
| Year | 2019 | Publication | Semiconductor science and technology | Abbreviated Journal | Semicond Sci Tech |
| Volume | Issue | Pages |
|||
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Moiré fringes are used throughout a wide variety of applications in physics and engineering to bring out small variations in an underlying lattice by comparing with another reference lattice. This method was recently demonstrated in Scanning Transmission Electron Microscopy imaging to provide local strain measurement in crystals by comparing the crystal lattice with the scanning raster that then serves as the reference. The images obtained in this way contain a beating fringe pattern with a local period that represents the deviation of the lattice from the reference. In order to obtain the actual strain value, a region containing a full period of the fringe is required, which results in a compromise between strain sensitivity and spatial resolution. In this paper we propose an advanced setup making use of an optimised scanning pattern and a novel phase stepping demodulation scheme. We demonstrate the novel method on a series of 16 nm Si-Ge semiconductor FinFET devices in which strain plays a crucial role in modulating the charge carrier mobility. The obtained results are compared with both Nano-beam diffraction and the recently proposed Bessel beam diffraction technique. The setup provides a much improved spatial resolution over conventional moiré imaging in STEM while at the same time being fast and requiring no specialised diffraction camera as opposed to the diffraction techniques we compare to. |
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| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000537721200002 | Publication Date | 2019-11-29 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0268-1242 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.305 | Times cited | 8 | Open Access | |
| Notes | The Qu-Ant-EM microscope and the direct electron detector used in the diffraction experiments was partly funded by the Hercules fund from the Flemish Government. This project has received funding from the GOA project “Solarpaint” of the University of Antwerp. We would also like to thank Dr. Thomas Nuytten and Prof. Dr. Wilfried Vandervorst from IMEC, Leuven for their continuous support and collaboration with the project. | Approved | Most recent IF: 2.305 | ||
| Call Number | EMAT @ emat @c:irua:165794 | Serial | 5445 | ||
| 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 | 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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| 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 | Clark, L.; Béché, A.; Guzzinati, G.; Lubk, A.; Mazilu, M.; Van Boxem, R.; Verbeeck, J. | ||||
| Title | Exploiting lens aberrations to create electron-vortex beams | Type | A1 Journal article | ||
| Year | 2013 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
| Volume | 111 | Issue | 6 | Pages |
064801-64805 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | A model for a new electron-vortex beam production method is proposed and experimentally demonstrated. The technique calls on the controlled manipulation of the degrees of freedom of the lens aberrations to achieve a helical phase front. These degrees of freedom are accessible by using the corrector lenses of a transmission electron microscope. The vortex beam is produced through a particular alignment of these lenses into a specifically designed astigmatic state and applying an annular aperture in the condenser plane. Experimental results are found to be in good agreement with simulations. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | New York, N.Y. | Editor | ||
| Language | Wos | 000322921200009 | Publication Date | 2013-08-08 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0031-9007;1079-7114; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 8.462 | Times cited | 66 | Open Access | |
| Notes | Vortex; Esteem2; Countatoms; FWO; Esteem2jra3 ECASJO; | Approved | Most recent IF: 8.462; 2013 IF: 7.728 | ||
| Call Number | UA @ lucian @ c:irua:109340UA @ admin @ c:irua:109340 | Serial | 1148 | ||
| Permanent link to this record | |||||
| Author | Van Aert, S.; De Backer, A.; Jones, L.; Martinez, G.T.; Béché, A.; Nellist, P.D. | ||||
| Title | Control of Knock-On Damage for 3D Atomic Scale Quantification of Nanostructures: Making Every Electron Count in Scanning Transmission Electron Microscopy | Type | A1 Journal article | ||
| Year | 2019 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
| Volume | 122 | Issue | 6 | Pages |
066101 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Understanding nanostructures down to the atomic level is the key to optimizing the design of advancedmaterials with revolutionary novel properties. This requires characterization methods capable of quantifying the three-dimensional (3D) atomic structure with the highest possible precision. A successful approach to reach this goal is to count the number of atoms in each atomic column from 2D annular dark field scanning transmission electron microscopy images. To count atoms with single atom sensitivity, a minimum electron dose has been shown to be necessary, while on the other hand beam damage, induced by the high energy electrons, puts a limit on the tolerable dose. An important challenge is therefore to develop experimental strategies to optimize the electron dose by balancing atom-counting fidelity vs the risk of knock-on damage. To achieve this goal, a statistical framework combined with physics-based modeling of the dose-dependent processes is here proposed and experimentally verified. This model enables an investigator to theoretically predict, in advance of an experimental measurement, the optimal electron dose resulting in an unambiguous quantification of nanostructures in their native state with the highest attainable precision. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000458824200008 | Publication Date | 2019-02-13 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0031-9007 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 8.462 | Times cited | 3 | Open Access | OpenAccess |
| Notes | 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) through project fundings (WO.010.16N, G.0934.17N, G.0502.18N, G.0267.18N), and a grant to A. D. B. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement No. 312483— ESTEEM2 (Integrated Infrastructure Initiative-I3) and the UK EPSRC (Grant No. EP/M010708/1). | Approved | Most recent IF: 8.462 | ||
| Call Number | EMAT @ emat @UA @ admin @ c:irua:157175 | Serial | 5156 | ||
| Permanent link to this record | |||||
| Author | Gao, C.; Hofer, C.; Jannis, D.; Béché, A.; Verbeeck, J.; Pennycook, T.J. | ||||
| Title | Overcoming contrast reversals in focused probe ptychography of thick materials: An optimal pipeline for efficiently determining local atomic structure in materials science | Type | A1 Journal article | ||
| Year | 2022 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
| Volume | 121 | Issue | 8 | Pages |
081906 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Ptychography provides highly efficient imaging in scanning transmission electron microscopy (STEM), but questions have remained over its applicability to strongly scattering samples such as those most commonly seen in materials science. Although contrast reversals can appear in ptychographic phase images as the projected potentials of the sample increase, we show here how these can be easily overcome by a small amount of defocus. The amount of defocus is small enough that it not only can exist naturally when focusing using the annular dark field (ADF) signal but can also be adjusted post acquisition. The ptychographic images of strongly scattering materials are clearer at finite doses than other STEM techniques and can better reveal light atomic columns within heavy lattices. In addition, data for ptychography can now be collected simultaneously with the fastest of ADF scans. This combination of sensitivity and interpretability presents an ideal workflow for materials science. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000844403300006 | Publication Date | 2022-08-22 | |
| 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 | 4 | Times cited | 9 | Open Access | OpenAccess |
| Notes | European Research Council, 802123-HDEM ; HORIZON EUROPE European Research Council, 823717-ESTEEM3 ; Fonds Wetenschappelijk Onderzoek, G042920N ; Fonds Wetenschappelijk Onderzoek, G042820N ; Horizon 2020 Framework Programme, 101017720 ; Fonds Wetenschappelijk Onderzoek, G013122N ; esteem3reported; esteem3jra | Approved | Most recent IF: 4 | ||
| Call Number | EMAT @ emat @c:irua:190670 | Serial | 7120 | ||
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| 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. | ||||
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| 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 | ||
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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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| Corporate Author | Thesis | ||||
| 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 | Velazco, A.; Nord, M.; Béché, A.; Verbeeck, J. | ||||
| Title | Evaluation of different rectangular scan strategies for STEM imaging | Type | A1 Journal article | ||
| Year | 2020 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | Issue | Pages |
113021 | ||
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | STEM imaging is typically performed by raster scanning a focused electron probe over a sample. Here we investigate and compare three different scan patterns, making use of a programmable scan engine that allows to arbitrarily set the sequence of probe positions that are consecutively visited on the sample. We compare the typical raster scan with a so-called ‘snake’ pattern where the scan direction is reversed after each row and a novel Hilbert scan pattern that changes scan direction rapidly and provides an homogeneous treatment of both scan directions. We experimentally evaluate the imaging performance on a single crystal test sample by varying dwell time and evaluating behaviour with respect to sample drift. We demonstrate the ability of the Hilbert scan pattern to more faithfully represent the high frequency content of the image in the presence of sample drift. It is also shown that Hilbert scanning provides reduced bias when measuring lattice parameters from the obtained scanned images while maintaining similar precision in both scan directions which is especially important when e.g. performing strain analysis. Compared to raster scanning with flyback correction, both snake and Hilbert scanning benefit from dose reduction as only small probe movement steps occur. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000544042800007 | Publication Date | 2020-05-21 | |
| 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 | 2.2 | Times cited | 13 | Open Access | OpenAccess |
| Notes | A.V., A.B. and J.V. acknowledge funding through FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy') from the Flanders Research Fund. M.N. received support for this work from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 838001. J.V acknowledges funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. | Approved | Most recent IF: 2.2; 2020 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:169225 | Serial | 6369 | ||
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| Author | Prabhakara, V.; Jannis, D.; Guzzinati, G.; Béché, A.; Bender, H.; Verbeeck, J. | ||||
| Title | HAADF-STEM block-scanning strategy for local measurement of strain at the nanoscale | Type | A1 Journal article | ||
| Year | 2020 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 219 | Issue | Pages |
113099 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Lattice strain measurement of nanoscale semiconductor devices is crucial for the semiconductor industry as strain substantially improves the electrical performance of transistors. High resolution scanning transmission electron microscopy (HR-STEM) imaging is an excellent tool that provides spatial resolution at the atomic scale and strain information by applying Geometric Phase Analysis or image fitting procedures. However, HR-STEM images regularly suffer from scanning distortions and sample drift during image acquisition. In this paper, we propose a new scanning strategy that drastically reduces artefacts due to drift and scanning distortion, along with extending the field of view. It consists of the acquisition of a series of independent small subimages containing an atomic resolution image of the local lattice. All subimages are then analysed individually for strain by fitting a nonlinear model to the lattice images. The method allows flexible tuning of spatial resolution and the field of view within the limits of the dynamic range of the scan engine while maintaining atomic resolution sampling within the subimages. The obtained experimental strain maps are quantitatively benchmarked against the Bessel diffraction technique. We demonstrate that the proposed scanning strategy approaches the performance of the diffraction technique while having the advantage that it does not require specialized diffraction cameras. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000594768500006 | Publication Date | 2020-09-01 | |
| 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 | 2.2 | Times cited | 4 | Open Access | OpenAccess |
| Notes | A.B. D.J. and J.V. acknowledge funding through FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy') from the Flanders Research Fund. J.V acknowledges funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. The Qu-Ant-EM microscope and the direct electron detector used in the diffraction experiments was partly funded by the Hercules fund from the Flemish Government. This project has received funding from the GOA project “Solarpaint” of the University of Antwerp. GG acknowledges support from a postdoctoral fellowship grant from the Fonds Wetenschappelijk Onderzoek – Vlaanderen (FWO). Special thanks to Dr. Thomas Nuytten, Prof. Dr. Wilfried Vandervorst, Dr. Paola Favia, Dr. Olivier Richard from IMEC, Leuven and Prof. Dr. Sara Bals from EMAT, Antwerp for their continuous support and collaboration with the project and to the IMEC processing group for the device fabrication. | Approved | Most recent IF: 2.2; 2020 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:172485 | Serial | 6404 | ||
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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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| Publisher | Place of Publication | Editor | |||
| 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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