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Author | Schattschneider, P.; Stöger-Pollach, M.; Löffler, S.; Steiger-Thirsfeld, A.; Hell, J.; Verbeeck, J. | ||||
Title | Sub-nanometer free electrons with topological charge | Type | A1 Journal article | ||
Year | 2012 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 115 | Issue | Pages | 21-25 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The holographic mask technique is used to create freely moving electrons with quantized angular momentum. With electron optical elements they can be focused to vortices with diameters below the nanometer range. The understanding of these vortex beams is important for many applications. Here, we produce electron vortex beams and compare them to a theory of electrons with topological charge. The experimental results show excellent agreement with simulations. As an immediate application, fundamental experimental parameters like spherical aberration and partial coherence are determined. (C) 2012 Elsevier B.V. All rights reserved. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000302962400004 | Publication Date | 2012-01-30 | |
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 | 24 | Open Access | |
Notes | vortex ECASJO_; | Approved | Most recent IF: 2.843; 2012 IF: 2.470 | ||
Call Number | UA @ lucian @ c:irua:98279 | Serial | 3344 | ||
Permanent link to this record | |||||
Author | Ke, X.; Bals, S.; Romo Negreira, A.; Hantschel, T.; Bender, H.; Van Tendeloo, G. | ||||
Title | TEM sample preparation by FIB for carbon nanotube interconnects | Type | A1 Journal article | ||
Year | 2009 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 109 | Issue | 11 | Pages | 1353-1359 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A powerful method to study carbon nanotubes (CNTs) grown in patterned substrates for potential interconnects applications is transmission electron microscopy (TEM). However, high-quality TEM samples are necessary for such a study. Here, TEM specimen preparation by focused ion beam (FIB) has been used to obtain lamellae of patterned samples containing CNTs grown inside contact holes. A dual-cap Pt protection layer and an extensive 5 kV cleaning procedure are applied in order to preserve the CNTs and avoid deterioration during milling. TEM results show that the inner shell structure of the carbon nanotubes has been preserved, which proves that focused ion beam is a useful technique to prepare TEM samples of CNT interconnects. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000270765800006 | Publication Date | 2009-07-11 | |
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 | 21 | Open Access | |
Notes | Esteem 026019; Iap | Approved | Most recent IF: 2.843; 2009 IF: 2.067 | ||
Call Number | UA @ lucian @ c:irua:79074 | Serial | 3485 | ||
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Author | van Landuyt, J. | ||||
Title | The evolution of HVEM application in antwerp | Type | A1 Journal article | ||
Year | 1991 | Publication | Ultramicroscopy T2 – 2nd Osaka International Symp.on High-Voltage Electron Microscopy : New Directions and Future Aspects of High Voltage Electron Microscopy, November 8-10, 1990, Osaka University, Osaka, Japan | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 39 | Issue | 1-4 | Pages | 287-298 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The evolution of the use of the 1250 keV high-voltage electron microscope in Antwerp is sketched by illustrating a non-exhaustive set of examples in various fields. One of the main present fields of application gets some more attention, i.e. the defect studies as produced by processing steps in microelectronic devices: (i) strain-induced dislocations at the edges of various device isolation interlayers, (ii) morphologies resulting from high-energy ion implantation creating buried layers for silicon on insulator (SOI) and other implantation technologies. | ||||
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Corporate Author | Thesis | ||||
Publisher | Elsevier | Place of Publication | Amsterdam | Editor | |
Language | Wos | A1991GY23100034 | Publication Date | 2002-10-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 2.436 | Times cited | Open Access | ||
Notes | Approved | PHYSICS, APPLIED 47/145 Q2 # | |||
Call Number | UA @ lucian @ c:irua:95973 | Serial | 3579 | ||
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Author | Verbeeck, J.; Bertoni, G.; Schattschneider, P. | ||||
Title | The Fresnel effect of a defocused biprism on the fringes in inelastic holography | Type | A1 Journal article | ||
Year | 2008 | Publication | Ultramicroscopy T2 – 16th International Microscopy Congress, SEP 03-08, 2006, Sapporo, JAPAN | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 108 | Issue | 3 | Pages | 263-269 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We present energy filtered holography experiments on a thin foil of Al. By propagating the reduced density matrix of the probe electron through the microscope, we quantitatively predict the fringe contrast as a function of energy loss. Fringe contrast simulations include the effect of Fresnel fringes created at the edges of the defocused biprism, the effect of partial coherence in combination with inelastic scattering, and the effect of a finite energy distribution of the incoming beam. (c) 2007 Elsevier B.V. All rights reserved. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000253389100011 | Publication Date | 2007-11-02 | |
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 | |
Notes | Fwo G.0147.06; Esteem 026019 | Approved | Most recent IF: 2.843; 2008 IF: 2.629 | ||
Call Number | UA @ lucian @ c:irua:104035 | Serial | 3582 | ||
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Author | Schattschneider, P.; Verbeeck, J. | ||||
Title | Theory of free electron vortices | Type | A1 Journal article | ||
Year | 2011 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 111 | Issue | 9/10 | Pages | 1461-1468 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The recent creation of electron vortex beams and their first practical application motivates a better understanding of their properties. Here, we develop the theory of free electron vortices with quantized angular momentum, based on solutions of the Schrödinger equation for cylindrical boundary conditions. The principle of transformation of a plane wave into vortices with quantized angular momentum, their paraxial propagation through round magnetic lenses, and the effect of partial coherence are discussed. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000300461200002 | Publication Date | 2011-07-26 | |
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 | 57 | Open Access | |
Notes | Esteem 026019 | Approved | Most recent IF: 2.843; 2011 IF: 2.471 | ||
Call Number | UA @ lucian @ c:irua:91882 | Serial | 3617 | ||
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Author | van den Broek, W.; Van Aert, S.; Goos, P.; van Dyck, D. | ||||
Title | Throughput maximization of particle radius measurements by balancing size and current of the electron probe | Type | A1 Journal article | ||
Year | 2011 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 111 | Issue | 7 | Pages | 940-947 |
Keywords | A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT); Vision lab | ||||
Abstract | In thispaperweinvestigatewhichprobesizemaximizesthethroughputwhenmeasuringtheradiusof nanoparticlesinhighangleannulardarkfieldscanningtransmissionelectronmicroscopy(HAADFSTEM). The sizeandthecorrespondingcurrentoftheelectronprobedeterminetheprecisionoftheestimateofa particlesradius.Maximizingthroughputmeansthatamaximumnumberofparticlesshouldbeimaged withinagiventimeframe,sothataprespecifiedprecisionisattained.WeshowthatBayesianstatistical experimentaldesignisaveryusefulapproachtodeterminetheoptimalprobesizeusingacertainamount of priorknowledgeaboutthesample.Thedependenceoftheoptimalprobesizeonthedetectorgeometry and thediameter,variabilityandatomicnumberoftheparticlesisinvestigated.Anexpressionforthe optimalprobesizeintheabsenceofanykindofpriorknowledgeaboutthespecimenisderivedaswell. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000300461000026 | Publication Date | 2010-11-25 | |
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 | 7 | Open Access | |
Notes | Approved | Most recent IF: 2.843; 2011 IF: 2.471 | |||
Call Number | UA @ lucian @ c:irua:89657 | Serial | 3659 | ||
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Author | van den Broek, W.; Verbeeck, J.; Schryvers, D.; de Backer, S.; Scheunders, P. | ||||
Title | Tomographic spectroscopic imaging; an experimental proof of concept | Type | A1 Journal article | ||
Year | 2009 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 109 | Issue | 4 | Pages | 296-303 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
Abstract | Recording the electron energy loss spectroscopy data cube with a series of energy filtered images is a dose inefficient process because the energy slit blocks most of the electrons. When recording the data cube by scanning an electron probe over the sample, perfect dose efficiency is attained; but due to the low current in nanoprobes, this often is slower, with a smaller field of view. In W. Van den Broek et al. [Ultramicroscopy, 106 (2006) 269], we proposed a new method to record the data cube, which is more dose efficient than an energy filtered series. It produces a set of projections of the data cube and then tomographically reconstructs it. In this article, we demonstrate these projections in practice, we present a simple geometrical model that allows for quantification of the projection angles and we present the first successful experimental reconstruction, all on a standard post-column instrument. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000265345400003 | Publication Date | 2008-12-10 | |
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 | 1 | Open Access | |
Notes | Esteem 026019 | Approved | Most recent IF: 2.843; 2009 IF: 2.067 | ||
Call Number | UA @ lucian @ c:irua:77271 | Serial | 3671 | ||
Permanent link to this record | |||||
Author | van Aarle, W.; Palenstijn, W.J.; De Beenhouwer, J.; Altantzis, T.; Bals, S.; Batenburg, K.J.; Sijbers, J. | ||||
Title | The ASTRA Toolbox: A platform for advanced algorithm development in electron tomography | Type | A1 Journal article | ||
Year | 2015 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 157 | Issue | 157 | Pages | 35-47 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
Abstract | We present the ASTRA Toolbox as an open platform for 3D image reconstruction in tomography. Most of the software tools that are currently used in electron tomography offer limited flexibility with respect to the geometrical parameters of the acquisition model and the algorithms used for reconstruction. The ASTRA Toolbox provides an extensive set of fast and flexible building blocks that can be used to develop advanced reconstruction algorithms, effectively removing these limitations. We demonstrate this flexibility, the resulting reconstruction quality, and the computational efficiency of this toolbox by a series of experiments, based on experimental dual-axis tilt series. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000361002400005 | Publication Date | 2015-05-06 |
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 | 562 | Open Access | OpenAccess |
Notes | The authors acknowledge financial support from the iMinds ICONMetroCT project,the IWT SBO Tom Food project and from the Netherlands Organisation for Scientific Research (NWO),Project no. 639.072.005. Networking support was provided by the EXTREMA COST Action MP 1207. Sara Bals acknowledges financial support from the European Research Council (ERC Starting Grant #335078 COLOURATOMS).; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); | Approved | Most recent IF: 2.843; 2015 IF: 2.436 | ||
Call Number | c:irua:127834 | Serial | 3974 | ||
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Author | Zanaga, D.; Altantzis, T.; Sanctorum, J.; Freitag, B.; Bals, S. | ||||
Title | An alternative approach for ζ-factor measurement using pure element nanoparticles | Type | A1 Journal article | ||
Year | 2016 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 164 | Issue | 164 | Pages | 11-16 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | It is very challenging to measure the chemical composition of hetero nanostructures in a reliable and quantitative manner. Here, we propose a novel and straightforward approach that can be used to quantify energy dispersive X-ray spectra acquired in a transmission electron microscope. Our method is based on a combination of electron tomography and the so-called ζ-factor technique. We will demonstrate the reliability of our approach as well as its applicability by investigating Au-Ag and Au-Pt hetero nanostructures. Given its simplicity, we expect that the method could become a new standard in the field of chemical characterization using electron microscopy. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000373526200002 | Publication Date | 2016-03-10 | |
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 | 19 | Open Access | OpenAccess |
Notes | The authors acknowledge financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS) and the European Union under the FP7 (Integrated Infrastructure Initiative N. 312483 – ESTEEM2). The authors would also like to thank Luis M. Liz-Marzán, Ana Sánchez-Iglesias, Stefanos Mourdikoudis and Cristina Fernández-López for sample provision and useful discussions.; esteem2jra4; ECASSara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @ | Serial | 4019 | ||
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Author | Lobato, I.; Van Aert, S.; Verbeeck, J. | ||||
Title | Progress and new advances in simulating electron microscopy datasets using MULTEM | Type | A1 Journal article | ||
Year | 2016 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 168 | Issue | 168 | Pages | 17-27 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A new version of the open source program MULTEM is presented here. It includes a graphical user interface, tapering truncation of the atomic potential, CPU multithreading functionality, single/double precision calculations, scanning transmission electron microscopy (STEM) simulations using experimental detector sensitivities, imaging STEM (ISTEM) simulations, energy filtered transmission electron microscopy (EFTEM) simulations, STEM electron energy loss spectroscopy (EELS) simulations along with other improvements in the algorithms. We also present a mixed channeling approach for the calculation of inelastic excitations, which allows one to considerably speed up time consuming EFTEM/STEM-EELS calculations. | ||||
Address | EMAT, University of Antwerp, Department of Physics, Groenenborgerlaan 171, B-2020 Antwerp, Belgium | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000380754100003 | Publication Date | 2016-06-11 |
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 | 43 | Open Access | |
Notes | The authors acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative. Reference No. 312483- ESTEEM2. The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0369.15N and G.0368.15N).; esteem2jra3; esteem2na3; esteem2_jra2 | Approved | Most recent IF: 2.843 | ||
Call Number | c:irua:134088 c:irua:134088UA @ admin @ c:irua:134088 | Serial | 4093 | ||
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Author | Béché, A.; Juchtmans, R.; Verbeeck, J. | ||||
Title | Efficient creation of electron vortex beams for high resolution STEM imaging | Type | A1 Journal article | ||
Year | 2017 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 178 | Issue | 178 | Pages | 12-19 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The recent discovery of electron vortex beams carrying quantised angular momentum in the TEM has led to an active field of research, exploring a variety of potential applications including the possibility of mapping magnetic states at the atomic scale. A prerequisite for this is the availability of atomic sized electron vortex beams at high beam current and mode purity. In this paper we present recent progress showing that by making use of the Aharonov-Bohm effect near the tip of a long single domain ferromagnetic Nickel needle, a very efficient aperture for the production of electron vortex beams can be realised. The aperture transmits more than 99% of all electrons and provides a vortex mode purity of up to 92%. Placing this aperture in the condenser plane of a state of the art Cs corrected microscope allows us to demonstrate atomic resolution HAADF STEM images with spatial resolution better than 1 Angstrom, in agreement with theoretical expectations and only slightly inferior to the performance of a non-vortex probe on the same instrument. | ||||
Address | EMAT, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000403862900003 | Publication Date | 2016-05-10 |
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 | 30 | Open Access | OpenAccess |
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. J.V. acknowledges funding from FWO project G.0044.13N ('Charge ordering').; ECASJO_; | Approved | Most recent IF: 2.843 | ||
Call Number | c:irua:134085 c:irua:134085UA @ admin @ c:irua:134085 | Serial | 4094 | ||
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Author | Muller-Caspary, K.; Krause, F.F.; Grieb, T.; Loffler, S.; Schowalter, M.; Béché, A.; Galioit, V.; Marquardt, D.; Zweck, J.; Schattschneider, P.; Verbeeck, J.; Rosenauer, A. | ||||
Title | Measurement of atomic electric fields and charge densities from average momentum transfers using scanning transmission electron microscopy | Type | A1 Journal article | ||
Year | 2016 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 178 | Issue | 178 | Pages | 62-80 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | This study sheds light on the prerequisites, possibilities, limitations and interpretation of high-resolution differential phase contrast (DPC) imaging in scanning transmission electron microscopy (STEM). We draw particular attention to the well-established DPC technique based on segmented annular detectors and its relation to recent developments based on pixelated detectors. These employ the expectation value of the momentum transfer as a reliable measure of the angular deflection of the STEM beam induced by an electric field in the specimen. The influence of scattering and propagation of electrons within the specimen is initially discussed separately and then treated in terms of a two-state channeling theory. A detailed simulation study of GaN is presented as a function of specimen thickness and bonding. It is found that bonding effects are rather detectable implicitly, e.g., by characteristics of the momentum flux in areas between the atoms than by directly mapping electric fields and charge densities. For strontium titanate, experimental charge densities are compared with simulations and discussed with respect to experimental artifacts such as scan noise. Finally, we consider practical issues such as figures of merit for spatial and momentum resolution, minimum electron dose, and the mapping of larger-scale, built-in electric fields by virtue of data averaged over a crystal unit cell. We find that the latter is possible for crystals with an inversion center. Concerning the optimal detector design, this study indicates that a sampling of 5mrad per pixel is sufficient in typical applications, corresponding to approximately 10x10 available pixels. | ||||
Address | Institut fur Festkr perphysik, Universitat Bremen, Otto-Hahn-Allee 1, 28359 Bremen, Germany | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000403862900009 | Publication Date | 2016-05-12 |
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 | 93 | Open Access | |
Notes | K.M.-C. acknowledges support from the Deutsche Forschungsgemeinschaft (DFG) under contract MU3660/1-1. This work was further supported by the DFG under contract RO2057/4-2 and O2057/11-1. J.V. and A.B. acknowledge funding from the European Research Council (ERC) under the 7th Framework Program (FP7), and ERC Starting Grant No. 278510-VORTEX. Experimental results are obtained on the Qu-Ant-EM microscope partly funded by the Hercules fund from the Flemish government. J.V. also acknowledges funding through a GOA project “Solarpaint” of the University of Antwerp. SL and PS acknowledge financial support by the Austrian Science Fund (FWF) under grants No. I543-N20 and J3732-N27. ECASJO_; | Approved | Most recent IF: 2.843 | ||
Call Number | c:irua:134125UA @ admin @ c:irua:134125 | Serial | 4098 | ||
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Author | Goris, B.; Meledina, M.; Turner, S.; Zhong, Z.; Batenburg, K.J.; Bals, S. | ||||
Title | Three dimensional mapping of Fe dopants in ceria nanocrystals using direct spectroscopic electron tomography | Type | A1 Journal article | ||
Year | 2016 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 171 | Issue | 171 | Pages | 55-62 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Electron tomography is a powerful technique for the 3D characterization of the morphology of nanostructures. Nevertheless, resolving the chemical composition of complex nanostructures in 3D remains challenging and the number of studies in which electron energy loss spectroscopy (EELS) is combined with tomography is limited. During the last decade, dedicated reconstruction algorithms have been developed for HAADF-STEM tomography using prior knowledge about the investigated sample. Here, we will use the prior knowledge that the experimental spectrum of each reconstructed voxel is a linear combination of a well-known set of references spectra in a so-called direct spectroscopic tomography technique. Based on a simulation experiment, it is shown that this technique provides superior results in comparison to conventional reconstruction methods for spectroscopic data, especially for spectrum images containing a relatively low signal to noise ratio. Next, this technique is used to investigate the spatial distribution of Fe dopants in Fe:Ceria nanoparticles in 3D. It is shown that the presence of the Fe2+ dopants is correlated with a reduction of the Ce atoms from Ce4+ towards Ce3+. In addition, it is demonstrated that most of the Fe dopants are located near the voids inside the nanoparticle. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000389106200007 | Publication Date | 2016-09-06 | |
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 | 13 | Open Access | OpenAccess |
Notes | The work was supported by the Research Foundation Flanders (FWO Vlaanderen) by project funding (G038116N, 3G004613) and by a post-doctoral research grants to B.G. S.B. acknowledges funding from the European Research Council (Starting Grant no. COLOURATOMS 335078). K.J.B. acknowledges funding from The Netherlands Organization for Scientific Research (NWO) (program 639.072.005.). We would like to thank Dr. Hilde Poelman, Dr. Vladimir Galvita and Prof. Dr. Guy B. Marin for the synthesis of the investigated sample.; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); | Approved | Most recent IF: 2.843 | ||
Call Number | c:irua:135185 c:irua:135185 | Serial | 4123 | ||
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Author | Kirilenko, D.A.; Brunkov, P.N. | ||||
Title | Measuring the height-to-height correlation function of corrugation in suspended graphene | Type | A1 Journal article | ||
Year | 2016 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 165 | Issue | 165 | Pages | 1-7 |
Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
Abstract | Nanocorrugation of 2D crystals is an important phenomenon since it affects their electronic and mechanical properties. The corrugation may have various sources; one of them is flexural phonons that, in particular, are responsible for the thermal conductivity of graphene. A study of corrugation of just the suspended graphene can reveal much of valuable information on the physics of this complicated phenomenon. At the same time, the suspended crystal nanorelief can hardly be measured directly because of high flexibility of the 2D crystal. Moreover, the relief portion related to rapid out-of-plane oscillations (flexural phonons) is also inaccessible by such measurements. Here we present a technique for measuring the Fourier components of the height-height correlation function H(q) of suspended graphene which includes the effect of flexural phonons. The technique is based on the analysis of electron diffraction patterns. The H(q) is measured in the range of wavevectors q approximately 0.4-4.5nm(-1). At the upper limit of this range H(q) does follow the T/kappaq(4) law. So, we measured the value of suspended graphene bending rigidity kappa=1.2+/-0.4eV at ambient temperature T approximately 300K. At intermediate wave vectors, H(q) follows a slightly weaker exponent than theoretically predicted q(-3.15) but is closer to the results of the molecular dynamics simulation. At low wave vectors, the dependence becomes even weaker, which may be a sign of influence of charge carriers on the dynamics of undulations longer than 10nm. The technique presented can be used for studying physics of flexural phonons in other 2D materials. | ||||
Address | Ioffe Institute, Politekhnicheskaya ul. 26, 194021 St-Petersburg, Russia; ITMO University, Kronverksky pr. 49, 197101 St. Petersburg, Russia | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000375946200001 | Publication Date | 2016-03-28 |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | ||
Impact Factor | 2.843 | Times cited | 3 | Open Access | |
Notes | D.K. thanks the RFBR (Grant no. 16-32-60165) for the partial support of this research. The work was carried out in part at the Joint Research Center “Material Science and Characterization in Advanced Technologies” (St-Petersburg, Russia) under the financial support from the Ministry of Education and Science of the Russian Federation (Agreement 14.621.21.0007, 04.12.2014, id RFMEFI62114X0007, the use of the Jeol JEM-2100F microscope) and at EMAT, Universiteit Antwerpen (Antwerpen, Belgium), (the use of the FEI Tecnai G2 microscope). | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @ | Serial | 4124 | ||
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Author | Gonnissen, J.; De Backer, A.; den Dekker, A.J.; Sijbers, J.; Van Aert, S. | ||||
Title | Detecting and locating light atoms from high-resolution STEM images: The quest for a single optimal design | Type | A1 Journal article | ||
Year | 2016 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 170 | Issue | 170 | Pages | 128-138 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
Abstract | In the present paper, the optimal detector design is investigated for both detecting and locating light atoms from high resolution scanning transmission electron microscopy (HR STEM) images. The principles of detection theory are used to quantify the probability of error for the detection of light atoms from HR STEM images. To determine the optimal experiment design for locating light atoms, use is made of the so-called Cramer-Rao Lower Bound (CRLB). It is investigated if a single optimal design can be found for both the detection and location problem of light atoms. Furthermore, the incoming electron dose is optimised for both research goals and it is shown that picometre range precision is feasible for the estimation of the atom positions when using an appropriate incoming electron dose under the optimal detector settings to detect light atoms. | ||||
Address | Electron Microscopy for Materials Science (EMAT), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. Electronic address: sandra.vanaert@uantwerpen.be | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000386925500014 | Publication Date | 2016-07-26 |
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 | 6 | Open Access | |
Notes | The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0368.15, G.0369.15 and G.0374.13) and a postdoctoral research grant to A. De Backer. The research leading to these results has also received funding from the European Union Seventh Framework Programme [FP7/2007-2013] under Grant agreement no. 312483 (ESTEEM2). The authors would also like to thank A. Rosenauer for providing access to the STEMsim software and Gerardo T. Martinez for fruitful discussions.; esteem2_jra2 | Approved | Most recent IF: 2.843 | ||
Call Number | c:irua:135337 c:irua:135337 | Serial | 4128 | ||
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Author | De Backer, A.; van den Bos, K.H.W.; Van den Broek, W.; Sijbers, J.; Van Aert, S. | ||||
Title | StatSTEM: An efficient approach for accurate and precise model-based quantification of atomic resolution electron microscopy images | Type | A1 Journal article | ||
Year | 2016 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 171 | Issue | 171 | Pages | 104-116 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
Abstract | An efficient model-based estimation algorithm is introduced to quantify the atomic column positions and intensities from atomic resolution (scanning) transmission electron microscopy ((S)TEM) images. This algorithm uses the least squares estimator on image segments containing individual columns fully accounting for overlap between neighbouring columns, enabling the analysis of a large field of view. For this algorithm, the accuracy and precision with which measurements for the atomic column positions and scattering cross-sections from annular dark field (ADF) STEM images can be estimated, has been investigated. The highest attainable precision is reached even for low dose images. Furthermore, the advantages of the model-based approach taking into account overlap between neighbouring columns are highlighted. This is done for the estimation of the distance between two neighbouring columns as a function of their distance and for the estimation of the scattering cross-section which is compared to the integrated intensity from a Voronoi cell. To provide end-users this well-established quantification method, a user friendly program, StatSTEM, is developed which is freely available under a GNU public license. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000389106200014 | Publication Date | 2016-09-09 | |
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 | 43 | Open Access | |
Notes | The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0393.11, G.0064.10 and G.0374.13), a Ph.D. research grant to K.H.W. van den Bos, and a postdoctoral 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). A. Rosenauer is acknowledged for providing the STEMsim program.; esteem2_jra2 | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @ c:irua:135516 | Serial | 4280 | ||
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Author | Martinez, G.T.; van den Bos, K.H.W.; Alania, M.; Nellist, P.D.; Van Aert, S. | ||||
Title | Thickness dependence of scattering cross-sections in quantitative scanning transmission electron microscopy | Type | A1 Journal article | ||
Year | 2018 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 187 | Issue | Pages | 84-92 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | In quantitative scanning transmission electron microscopy (STEM), scattering cross-sections have been shown to be very sensitive to the number of atoms in a column and its composition. They correspond to the integrated intensity over the atomic column and they outperform other measures. As compared to atomic column peak intensities, which saturate at a given thickness, scattering cross-sections increase monotonically. A study of the electron wave propagation is presented to explain the sensitivity of the scattering cross-sections. Based on the multislice algorithm, we analyse the wave propagation inside the crystal and its link to the scattered signal for the different probe positions contained in the scattering cross-section for detector collection in the low-, middle- and high-angle regimes. The influence to the signal from scattering of neighbouring columns is also discussed. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000428131200011 | Publication Date | 2018-01-31 | |
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 | 4 | Open Access | Not_Open_Access: Available from 01.02.2020 |
Notes | The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings ( G.0374.13N , G.0369.15N , G.0368.15N and WO.010.16N ) and a PhD grant to K.H.W.v.d.B. The research leading to these results has received funding from the European Union 7th Framework Programme [ FP7 /2007-2013] under Grant agreement no. 312483 (ESTEEM2). The authors are grateful to A. Rosenauer for providing access to the StemSim software. | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @c:irua:149384 | Serial | 4809 | ||
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Author | Lobato, I.; Van Dyck, D. | ||||
Title | MULTEM : a new multislice program to perform accurate and fast electron diffraction and imaging simulations using graphics processing units with CUDA | Type | A1 Journal article | ||
Year | 2015 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 156 | Issue | 156 | Pages | 9-17 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
Abstract | The main features and the GPU implementation of the MULTEM program are presented and described. This new program performs accurate and fast multislice simulations by including higher order expansion of the multislice solution of the high energy Schrodinger equation, the correct subslicing of the three-dimensional potential and top-bottom surfaces. The program implements different kinds of simulation for CTEM, STEM, ED, PED, CBED, ADF-TEM and ABF-HC with proper treatment of the spatial and temporal incoherences. The multislice approach described here treats the specimen as amorphous material which allows a straightforward implementation of the frozen phonon approximation. The generalized transmission function for each slice is calculated when is needed and then discarded. This allows us to perform large simulations that can include millions of atoms and keep the computer memory requirements to a reasonable level. (C) 2015 Elsevier B.V. All rights reserved. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000361001800003 | Publication Date | 2015-04-28 | |
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 | 32 | Open Access | |
Notes | Approved | Most recent IF: 2.843; 2015 IF: 2.436 | |||
Call Number | UA @ lucian @ c:irua:127848 | Serial | 4209 | ||
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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. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
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 | Gonnissen, J.; De Backer, A.; den Dekker, A.J.; Sijbers, J.; Van Aert, S. | ||||
Title | Atom-counting in High Resolution Electron Microscopy: TEM or STEM – that's the question | Type | A1 Journal article | ||
Year | 2016 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 174 | Issue | 174 | Pages | 112-120 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
Abstract | In this work, a recently developed quantitative approach based on the principles of detection theory is used in order to determine the possibilities and limitations of High Resolution Scanning Transmission Electron Microscopy (HR STEM) and HR TEM for atom-counting. So far, HR STEM has been shown to be an appropriate imaging mode to count the number of atoms in a projected atomic column. Recently, it has been demonstrated that HR TEM, when using negative spherical aberration imaging, is suitable for atom-counting as well. The capabilities of both imaging techniques are investigated and compared using the probability of error as a criterion. It is shown that for the same incoming electron dose, HR STEM outperforms HR TEM under common practice standards, i.e. when the decision is based on the probability function of the peak intensities in HR TEM and of the scattering cross-sections in HR STEM. If the atom-counting decision is based on the joint probability function of the image pixel values, the dependence of all image pixel intensities as a function of thickness should be known accurately. Under this assumption, the probability of error may decrease significantly for atom-counting in HR TEM and may, in theory, become lower as compared to HR STEM under the predicted optimal experimental settings. However, the commonly used standard for atom-counting in HR STEM leads to a high performance and has been shown to work in practice. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000403342200013 | Publication Date | 2016-10-27 | |
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 | 2 | Open Access | |
Notes | The authors gratefully acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0368.15N, G.0369.15N, G.0374.13N, and WO.010.16N) and a postdoctoral grant to A. De Backer. The research leading to these results has received funding from the European Union Seventh Framework Programme [FP7/2007-2013] under Grant agreement no. 312483 (ESTEEM2). | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @ c:irua:137102 | Serial | 4315 | ||
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Author | Alania, M.; Altantzis, T.; De Backer, A.; Lobato, I.; Bals, S.; Van Aert, S. | ||||
Title | Depth sectioning combined with atom-counting in HAADF STEM to retrieve the 3D atomic structure | Type | A1 Journal article | ||
Year | 2016 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 177 | Issue | 177 | Pages | 36-42 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Aberration correction in scanning transmission electron microscopy (STEM) has greatly improved the lateral and depth resolution. When using depth sectioning, a technique during which a series of images is recorded at different defocus values, single impurity atoms can be visualised in three dimensions. In this paper, we investigate new possibilities emerging when combining depth sectioning and precise atom-counting in order to reconstruct nanosized particles in three dimensions. Although the depth resolution does not allow one to precisely locate each atom within an atomic column, it will be shown that the depth location of an atomic column as a whole can be measured precisely. In this manner, the morphology of a nanoparticle can be reconstructed in three dimensions. This will be demonstrated using simulations and experimental data of a gold nanorod. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000401219800006 | Publication Date | 2016-11-09 | |
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 | 13 | Open Access | OpenAccess |
Notes | The authors acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative. Reference No. 312483-ESTEEM2. S. Bals acknowledges funding from the European Research Council (Starting Grant No. COLOURATOMS 335078). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0369.15N and G.0368.15N) and a post-doctoral grant to A. De Backer and T. Altantzis. The authors are grateful to Professor Luis M. Liz-Marzán for providing the sample.; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @ c:irua:138015UA @ admin @ c:irua:138015 | Serial | 4316 | ||
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Author | Zanaga, D.; Altantzis, T.; Sanctorum, J.; Freitag, B.; Bals, S. | ||||
Title | An alternative approach for \zeta-factor measurement using pure element nanoparticles | Type | A1 Journal article | ||
Year | 2016 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 164 | Issue | Pages | 11-16 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | It is very challenging to measure the chemical composition of hetero nanostructures in a reliable and quantitative manner. Here, we propose a novel and straightforward approach that can be used to quantify energy dispersive X-ray spectra acquired in a transmission electron microscope. Our method is based on a combination of electron tomography and the so-called zeta-factor technique. We will demonstrate the reliability of our approach as well as its applicability by investigating Au-Ag and Au-Pt hetero nanostructures. Given its simplicity, we expect that the method could become a new standard in the field of chemical characterization using electron microscopy. (C) 2016 Elsevier B.V. All rights reserved. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000373526200002 | Publication Date | 2016-03-10 | |
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 | 19 | Open Access | OpenAccess |
Notes | ; The authors acknowledge financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS) and the European Union under the FP7 (Integrated Infrastructure Initiative N. 312483 – ESTEEM2). ; ecas_Sara | Approved | Most recent IF: 2.843 | ||
Call Number | UA @ lucian @ c:irua:133259 | Serial | 4439 | ||
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Author | Zhong, Z.; Goris, B.; Schoenmakers, R.; Bals, S.; Batenburg, K.J. | ||||
Title | A bimodal tomographic reconstruction technique combining EDS-STEM and HAADF-STEM | Type | A1 Journal article | ||
Year | 2017 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 174 | Issue | 174 | Pages | 35-45 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A three-dimensional (3D) chemical characterization of nanomaterials can be obtained using tomography based on high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) or energy dispersive X-ray spectroscopy (EDS) STEM. These two complementary techniques have both advantages and disadvantages. The Z-contrast images have good image quality but lack robustness in the compositional analysis, while the elemental maps give more element-specific information, but at a low signal-to-noise ratio and a longer exposure time. Our aim is to combine these two types of complementary information in one single tomographic reconstruction process. Therefore, an imaging model is proposed combining both HAADF-STEM and EDS-STEM. Based on this model, the elemental distributions can be reconstructed using both types of information simultaneously during the reconstruction process. The performance of the new technique is evaluated using simulated data and real experimental data. The results demonstrate that combining two imaging modalities leads to tomographic reconstructions with suppressed noise and enhanced contrast. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000403342200005 | Publication Date | 2016-12-11 | |
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 | 26 | Open Access | OpenAccess |
Notes | This research is supported by the Dutch Technology Foundation STW (http://www.stw.nl/), which is part of the Netherlands Organization for Scientific Research (NWO), and which is partly funded by the Ministry of Economic Affairs, Agriculture and Innovation under project number 13314. It is also supported by the Flemish research foundation (FWO Vlaanderen) by project funding (G038116N) and a postdoctoral research grant to B.G. Funding from the European Research Council (Starting Grant No. COLOURATOMS 335078) is acknowledged by S.B. The authors would like to thank Dr. Bernd Rieger and Dr. Richard Aveyard for useful discussions, and Prof. Dr. Luis M. Liz-Marzan for providing the investigated samples. We also acknowledge COST Action MP1207 for networking support. (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); saraecas; ECAS_Sara; | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @ c:irua:141719UA @ admin @ c:irua:141719 | Serial | 4484 | ||
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Author | Zhuge, X.; Jinnai, H.; Dunin-Borkowski, R.E.; Migunov, V.; Bals, S.; Cool, P.; Bons, A.-J.; Batenburg, K.J. | ||||
Title | Automated discrete electron tomography – Towards routine high-fidelity reconstruction of nanomaterials | Type | A1 Journal article | ||
Year | 2017 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 175 | Issue | 175 | Pages | 87-96 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) | ||||
Abstract | Electron tomography is an essential imaging technique for the investigation of morphology and 3D structure of nanomaterials. This method, however, suffers from well-known missing wedge artifacts due to a restricted tilt range, which limits the objectiveness, repeatability and efficiency of quantitative structural analysis. Discrete tomography represents one of the promising reconstruction techniques for materials science, potentially capable of delivering higher fidelity reconstructions by exploiting the prior knowledge of the limited number of material compositions in a specimen. However, the application of discrete tomography to practical datasets remains a difficult task due to the underlying challenging mathematical problem. In practice, it is often hard to obtain consistent reconstructions from experimental datasets. In addition, numerous parameters need to be tuned manually, which can lead to bias and non-repeatability. In this paper, we present the application of a new iterative reconstruction technique, named TVR-DART, for discrete electron tomography. The technique is capable of consistently delivering reconstructions with significantly reduced missing wedge artifacts for a variety of challenging data and imaging conditions, and can automatically estimate its key parameters. We describe the principles of the technique and apply it to datasets from three different types of samples acquired under diverse imaging modes. By further reducing the available tilt range and number of projections, we show that the proposed technique can still produce consistent reconstructions with minimized missing wedge artifacts. This new development promises to provide the electron microscopy community with an easy-to-use and robust tool for high-fidelity 3D characterization of nanomaterials. |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000403342500008 | Publication Date | 2017-01-24 | |
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 | 22 | Open Access | OpenAccess |
Notes | This work has been supported in part by the Stichting voor de Technische Wetenschappen (STW) through a personal grant (Veni,13610), and was in part by ExxonMobil Chemical Europe Inc. The authors further acknowledge financial support from the University of Antwerp through BOF GOA funding. S.B. acknowledges financial support from the European Research Council (ERC Starting Grant #335078-COLOURATOMS). R.D.B. is grateful for funding from the European Research Council under the European Union's Seventh Framework Programme (FP7/2007–2013)/ ERC grant agreement number 320832. Thomas Altantzis is gratefully acknowledged for acquiring the Anatase nanosheets dataset. (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); saraecas; ECAS_Sara; | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @ c:irua:141218UA @ admin @ c:irua:141218 | Serial | 4485 | ||
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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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Corporate Author | Thesis | ||||
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 | Stefan Löffler; Matthieu Bugnet; Nicolas Gauquelin; Sorin Lazar; Elias Assmann; Karsten Held; Gianluigi A. Botton; Peter Schattschneider | ||||
Title | Real-space mapping of electronic orbitals | Type | A1 Journal article | ||
Year | 2017 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 177 | Issue | 177 | Pages | 26-29 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Electronic states are responsible for most material properties, including chemical bonds, electrical and thermal conductivity, as well as optical and magnetic properties. Experimentally, however, they remain mostly elusive. Here, we report the real-space mapping of selected transitions between p and d states on the Ångström scale in bulk rutile (TiO2) using electron energy-loss spectrometry (EELS), revealing information on individual bonds between atoms. On the one hand, this enables the experimental verification of theoretical predictions about electronic states. On the other hand, it paves the way for directly investigating electronic states under conditions that are at the limit of the current capabilities of numerical simulations such as, e.g., the electronic states at defects, interfaces, and quantum dots. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000401219800004 | Publication Date | 2017-01-31 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record | |
Impact Factor | 2.843 | Times cited | Open Access | Not_Open_Access | |
Notes | ; St.L. thanks Walid Hetaba for discussions about WIEN2k. St.L. and P.S. thank Ralf Hambach and Ute Kaiser for many valuable discussions. M.B. thanks Vienna University of Technology for travel support. St.L. and P.S. acknowledge financial support by the Austrian Science Fund (FWF) under grant number 1543-N20, SFB F45 FOXSI; St.L. also acknowledges financial support by the Austrian Science Fund (FWF) under grant number J3732-N27. M.B., N.G., S.L. and G.A.B. performed the experimental work at the Canadian Center for Electron Microscopy, a national facility supported by McMaster University and the Natural Sciences and Engineering Research Council of Canada (NSERC). G.A.B. is grateful to NSERC for supporting this work. ; | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @ c:irua:142201 | Serial | 4539 | ||
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Author | Alania, M.; De Backer, A.; Lobato, I.; Krause, F.F.; Van Dyck, D.; Rosenauer, A.; Van Aert, S. | ||||
Title | How precise can atoms of a nanocluster be located in 3D using a tilt series of scanning transmission electron microscopy images? | Type | A1 Journal article | ||
Year | 2017 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 181 | Issue | 181 | Pages | 134-143 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
Abstract | In this paper, we investigate how precise atoms of a small nanocluster can ultimately be located in three dimensions (3D) from a tilt series of images acquired using annular dark field (ADF) scanning transmission electron microscopy (STEM). Therefore, we derive an expression for the statistical precision with which the 3D atomic position coordinates can be estimated in a quantitative analysis. Evaluating this statistical precision as a function of the microscope settings also allows us to derive the optimal experimental design. In this manner, the optimal angular tilt range, required electron dose, optimal detector angles, and number of projection images can be determined. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000411170800016 | Publication Date | 2016-12-15 | |
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 | 3 | Open Access | OpenAccess |
Notes | The authors acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative. Reference No. 312483-ESTEEM2. The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0369.15N, G.0368.15N, and WO.010.16N) and a post-doctoral grant to A. De Backer, and from the DFG under contract No. RO-2057/4-2. | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @ c:irua:144432 | Serial | 4618 | ||
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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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Publisher | Place of Publication | Editor | |||
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 | De wael, A.; De Backer, A.; Jones, L.; Nellist, P.D.; Van Aert, S. | ||||
Title | Hybrid statistics-simulations based method for atom-counting from ADF STEM images | Type | A1 Journal article | ||
Year | 2017 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 177 | Issue | 177 | Pages | 69-77 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A hybrid statistics-simulations based method for atom-counting from annular dark field scanning transmission electron microscopy (ADF STEM) images of monotype crystalline nanostructures is presented. Different atom-counting methods already exist for model-like systems. However, the increasing relevance of radiation damage in the study of nanostructures demands a method that allows atom-counting from low dose images with a low signal-to-noise ratio. Therefore, the hybrid method directly includes prior knowledge from image simulations into the existing statistics-based method for atom-counting, and accounts in this manner for possible discrepancies between actual and simulated experimental conditions. It is shown by means of simulations and experiments that this hybrid method outperforms the statistics-based method, especially for low electron doses and small nanoparticles. The analysis of a simulated low dose image of a small nanoparticle suggests that this method allows for far more reliable quantitative analysis of beam-sensitive materials. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000401219800010 | Publication Date | 2017-01-25 | |
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 | OpenAccess |
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 WO.010.16N), and a postdoctoral 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). The authors are grateful to G.T. Martinez for providing image simulations. | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @ c:irua:141718 | Serial | 4486 | ||
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Author | Vatanparast, M.; Egoavil, R.; Reenaas, T.W.; Verbeeck, J.; Holmestad, R.; Vullum, P.E. | ||||
Title | Bandgap measurement of high refractive index materials by off-axis EELS | Type | A1 Journal article | ||
Year | 2017 | Publication | Ultramicroscopy | Abbreviated Journal ![]() |
Ultramicroscopy |
Volume | 182 | Issue | Pages | 92-98 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | In the present work Cs aberration corrected and monochromated scanning transmission electron microscopy electron energy loss spectroscopy (STEM-EELS) has been used to explore experimental setups that allow bandgaps of high refractive index materials to be determined. Semi-convergence and collection angles in the mu rad range were combined with off-axis or dark field EELS to avoid relativistic losses and guided light modes in the low loss range to contribute to the acquired EEL spectra. Off-axis EELS further supressed the zero loss peak and the tail of the zero loss peak. The bandgap of several GaAs-based materials were successfully determined by simple regression analyses of the background subtracted EEL spectra. The presented set-up does not require that the acceleration voltage is set to below the. Cerenkov limit and can be applied over the entire acceleration voltage range of modern TEMs and for a wide range of specimen thicknesses. (C) 2017 Elsevier B.V. All rights reserved. | ||||
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Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000413436500013 | Publication Date | 2017-06-21 | |
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 | 2.843 | Times cited | 3 | Open Access | Not_Open_Access |
Notes | ; The authors would like to thank Professor Shu Min Wang and Mahdad Sadeghi at the Nanofabrication Laboratory at Chalmers University, Sweden for providing the samples. The Norwegian Research Council is acknowledged for funding the HighQ-IB project under contract no. 10415201. M.V. and T.W.R. acknowledge funding from the EEA Financial Mechanism 2009-2014 under the project contract no 23SEE/30.06.2014. 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) through the system of transnational access. R.E. and J.V. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp. ; | Approved | Most recent IF: 2.843 | ||
Call Number | UA @ lucian @ c:irua:146639UA @ admin @ c:irua:146639 | Serial | 4778 | ||
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