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Author Drijkoningen, S.; Pobedinskas, P.; Korneychuk, S.; Momot, A.; Balasubramaniam, Y.; Van Bael, M.K.; Turner, S.; Verbeeck, J.; Nesladekt, M.; Haenen, K.
Title On the Origin of Diamond Plates Deposited at Low Temperature Type A1 Journal article
Year 2017 Publication Crystal growth & design Abbreviated Journal Cryst Growth Des
Volume 17 Issue 8 Pages 4306-4314
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The crucial requirement for diamond growth at low temperatures, enabling a wide range of new applications, is a high plasma density at a low gas pressure, which leads to a low thermal load onto sensitive substrate materials. While these conditions are not within reach for resonance cavity plasma systems, linear antenna microwave delivery systems allow the deposition of high quality diamond films at temperatures around 400 degrees C and at pressures below 1 mbar. In this work the codeposition of high quality plates and octahedral diamond grains in nanocrystalline films is reported. In contrast to previous reports claiming the need for high temperatures (T >= 850 degrees C), low temperatures (320 degrees C <= T <= 410 degrees C) were sufficient to deposit diamond plate structures. Cross-sectional high resolution transmission electron microscopy studies show that these plates are faulty cubic diamond terminated by large {111} surface facets with very little sp(2) bonded carbon in the grain boundaries. Raman and electron energy loss spectroscopy studies confirm a high diamond quality, above 93% sp(3) carbon content. Three potential mechanisms, that can account for the initial development of the observed plates rich with stacking faults, and are based on the presence of impurities, are proposed.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000407089600031 Publication Date 2017-06-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1528-7483 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.055 Times cited 23 Open Access Not_Open_Access
Notes (up) ; The Research Foundation – Flanders (FWO) is gratefully acknowledged for financial support in the form of the Postdoctoral Fellowships of P.P. and S.T., contract G.0044.13N “Charge ordering” (S.K., J.V.), the Methusalem “Nano” network, and the Hercules-linear antenna and Raman equipment. ; Approved Most recent IF: 4.055
Call Number UA @ lucian @ c:irua:145735UA @ admin @ c:irua:145735 Serial 4746
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Author Das, S.; Rata, A.D.; Maznichenko, I., V; Agrestini, I.S.; Pippel, E.; Gauquelin, N.; Verbeeck, J.; Chen, K.; Valvidares, S.M.; Vasili, H.B.; Herrero-Martin, J.; Pellegrin, E.; Nenkov, K.; Herklotz, A.; Ernst, A.; Mertig, I.; Hu, Z.; Doerr, K.
Title Low-field switching of noncollinear spin texture at La0.7Sr0.3MnO3-SrRuO3interfaces Type A1 Journal article
Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 99 Issue 2 Pages 024416
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Interfaces of ferroic oxides can show complex magnetic textures which have strong impact on spintronics devices. This has been demonstrated recently for interfaces with insulating antiferromagnets such as BiFeO3. Here, noncollinear spin textures which can be switched in very low magnetic field are reported for conducting ferromagnetic bilayers of La0.7Sr0.3MnO3-SrRuO3 (LSMO-SRO). The magnetic order and switching are fundamentally different for bilayers coherently grown in reversed stacking sequence. The SRO top layer forms a persistent exchange spring which is antiferromagnetically coupled to LSMO and drives switching in low fields of a few milliteslas. Density functional theory reveals the crucial impact of the interface termination on the strength of Mn-Ru exchange coupling across the interface. The observation of an exchange spring agrees with ultrastrong coupling for the MnO2/SrO termination. Our results demonstrate low-field switching of noncollinear spin textures at an interface between conducting oxides, opening a pathway for manipulating and utilizing electron transport phenomena in controlled spin textures at oxide interfaces.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000455821400005 Publication Date 2019-01-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 19 Open Access OpenAccess
Notes (up) ; The research in Halle was supported by Deutsche Forschungsgemeinschaft (DFG), SFB 762 Functional Oxide Interfaces (Projects No. A9 and No. B1). K.C. benefited from support of the DFG (Project 600575). Discussions with M. Trassin, M. Ziese, H. M. Christen, E.-J. Guo, F. Grcondciel, M. Bibes, and H. N. Lee are gratefully acknowledged. N. G. and J. V. acknowledge funding under the GOA project “Solarpaint” of the University of Antwerp. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. ; Approved Most recent IF: 3.836
Call Number UA @ admin @ c:irua:156717 Serial 5255
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Author Spreitzer, M.; Klement, D.; Egoavil, R.; Verbeeck, J.; Kovac, J.; Zaloznik, A.; Koster, G.; Van Tendeloo, G.; Suvorov, D.; Rijnders, G.
Title Growth mechanism of epitaxial SrTiO3 on a (1 x 2) + (2 x 1) reconstructed Sr(1/2 ML)/Si(001) surface Type A1 Journal article
Year 2020 Publication Journal Of Materials Chemistry C Abbreviated Journal J Mater Chem C
Volume 8 Issue 2 Pages 518-527
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Sub-monolayer control over the growth at silicon-oxide interfaces is a prerequisite for epitaxial integration of complex oxides with the Si platform, enriching it with a variety of functionalities. However, the control over this integration is hindered by the intense reaction of the constituents. The most suitable buffer material for Si passivation is metallic strontium. When it is overgrown with a layer of SrTiO3 (STO) it can serve as a pseudo-substrate for the integration with functional oxides. In our study we determined a mechanism for epitaxial integration of STO with a (1 x 2) + (2 x 1) reconstructed Sr(1/2 ML)/Si(001) surface using all-pulsed laser deposition (PLD) technology. A detailed analysis of the initial deposition parameters was performed, which enabled us to develop a complete protocol for integration, taking into account the peculiarities of the PLD growth, STO critical thickness, and process thermal budget, in order to kinetically trap the reaction between STO and Si and thus to minimize the thickness of the interface layer. The as-prepared oxide layer exhibits STO(001)8Si(001) out-of-plane and STO[110]8Si[100] in-plane orientation and together with recent advances in large-scale PLD tools these results represent a new technological solution for the implementation of oxide electronics on demand.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000506852400036 Publication Date 2019-10-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7526; 2050-7534 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.4 Times cited 12 Open Access OpenAccess
Notes (up) ; The research was financially supported by the Slovenian Research Agency (Project No. P2-0091, J2-9237) and Ministry of Education, Science and Sport of the Republic of Slovenia (SIOX projects). This work was also funded by the European Union Council under the 7th Framework Program grant no. NMP3-LA-2010-246102 IFOX. J. V. and G. V. T. acknowledge funding from the Fund for Scientific Research Flanders under project no. G.0044.13N. ; Approved Most recent IF: 6.4; 2020 IF: 5.256
Call Number UA @ admin @ c:irua:165672 Serial 6298
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Author Bigiani, L.; Gasparotto, A.; Maccato, C.; Sada, C.; Verbeeck, J.; Andreu, T.; Morante, J.R.; Barreca, D.
Title Dual improvement of beta-MnO₂ oxygen evolution electrocatalysts via combined substrate control and surface engineering Type A1 Journal article
Year 2020 Publication Chemcatchem Abbreviated Journal Chemcatchem
Volume Issue Pages 1-10
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The development of catalysts with high intrinsic activity towards the oxygen evolution reaction (OER) plays a critical role in sustainable energy conversion and storage. Herein, we report on the development of efficient (photo)electrocatalysts based on functionalized MnO(2)systems. Specifically,beta-MnO(2)nanostructures grown by plasma enhanced-chemical vapor deposition on fluorine-doped tin oxide (FTO) or Ni foams were decorated with Co(3)O(4)or Fe(2)O(3)nanoparticles by radio frequency sputtering. Upon functionalization, FTO-supported materials yielded a performance increase with respect to bare MnO2, with current densities at 1.65 Vvs. the reversible hydrogen electrode (RHE) up to 3.0 and 3.5 mA/cm(2)in the dark and under simulated sunlight, respectively. On the other hand, the use of highly porous and conductive Ni foam substrates enabled to maximize cooperative interfacial effects between catalyst components. The best performing Fe2O3/MnO(2)system provided a current density of 17.9 mA/cm(2)at 1.65 Vvs. RHE, an overpotential as low as 390 mV, and a Tafel slope of 69 mV/decade under dark conditions, comparing favorably with IrO(2)and RuO(2)benchmarks. Overall, the control of beta-MnO2/substrate interactions and the simultaneous surface property engineering pave the way to an efficient energy generation from abundant natural resources.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000571229000001 Publication Date 2020-09-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1867-3880; 1867-3899 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.5 Times cited 5 Open Access Not_Open_Access
Notes (up) ; This work has been financially supported by Padova University DOR 2017-2019, P-DiSC #03BIRD2016-UNIPD and #03BIRD2018-UNIPD projects. A.G. acknowledges AMGA Foundation and INSTM Consortium. J.V. gratefully acknowledges funding from the GOA project “Solarpaint” of the University of Antwerp and the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717-ESTEEM3. ; esteem3TA; esteem3reported Approved Most recent IF: 4.5; 2020 IF: 4.803
Call Number UA @ admin @ c:irua:171949 Serial 6493
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Author Chen, B.; Gauquelin, N.; Jannis, D.; Cunha, D.M.; Halisdemir, U.; Piamonteze, C.; Lee, J.H.; Belhadi, J.; Eltes, F.; Abel, S.; Jovanovic, Z.; Spreitzer, M.; Fompeyrine, J.; Verbeeck, J.; Bibes, M.; Huijben, M.; Rijnders, G.; Koster, G.
Title Strain-engineered metal-to-insulator transition and orbital polarization in nickelate superlattices integrated on silicon Type A1 Journal article
Year 2020 Publication Advanced Materials Abbreviated Journal Adv Mater
Volume Issue Pages 2004995
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Epitaxial growth of SrTiO3 (STO) on silicon greatly accelerates the monolithic integration of multifunctional oxides into the mainstream semiconductor electronics. However, oxide superlattices (SLs), the birthplace of many exciting discoveries, remain largely unexplored on silicon. In this work, LaNiO3/LaFeO3 SLs are synthesized on STO-buffered silicon (Si/STO) and STO single-crystal substrates, and their electronic properties are compared using dc transport and X-ray absorption spectroscopy. Both sets of SLs show a similar thickness-driven metal-to-insulator transition, albeit with resistivity and transition temperature modified by the different amounts of strain. In particular, the large tensile strain promotes a pronounced Ni 3dx2-y2 orbital polarization for the SL grown on Si/STO, comparable to that reported for LaNiO3 SL epitaxially strained to DyScO3 substrate. Those results illustrate the ability to integrate oxide SLs on silicon with structure and property approaching their counterparts grown on STO single crystal, and also open up new prospects of strain engineering in functional oxides based on the Si platform.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000588146500001 Publication Date 2020-11-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0935-9648 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 29.4 Times cited 18 Open Access OpenAccess
Notes (up) ; This work is supported by the international M-ERA.NET project SIOX (project 4288) and H2020 project ULPEC (project 732642). M.S. acknowledges funding from Slovenian Research Agency (Grants No. J2-9237 and No. P2-0091). This work received support from the ERC CoG MINT (#615759) and from a PHC Van Gogh grant. M.B. thanks the French Academy of Science and the Royal Netherlands Academy of Arts and Sciences for supporting his stays in the Netherlands. This project has received funding as a transnational access project from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. N.G. and J.V. acknowledge GOA project “Solarpaint” of the University of Antwerp. ; esteem3TA; esteem3reported Approved Most recent IF: 29.4; 2020 IF: 19.791
Call Number UA @ admin @ c:irua:173516 Serial 6617
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Author Bigiani, L.; Andreu, T.; Maccato, C.; Fois, E.; Gasparotto, A.; Sada, C.; Tabacchi, G.; Krishnan, D.; Verbeeck, J.; Ramon Morante, J.; Barreca, D.
Title Engineering Au/MnO₂ hierarchical nanoarchitectures for ethanol electrochemical valorization Type A1 Journal article
Year 2020 Publication Journal Of Materials Chemistry A Abbreviated Journal J Mater Chem A
Volume 8 Issue 33 Pages 16902-16907
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The design of eco-friendly electrocatalysts for ethanol valorization is an open challenge towards sustainable hydrogen production. Herein we present an original fabrication route to effective electrocatalysts for the ethanol oxidation reaction (EOR). In particular, hierarchical MnO(2)nanostructures are grown on high-area nickel foam scaffolds by a plasma-assisted strategy and functionalized with low amounts of optimally dispersed Au nanoparticles. This strategy leads to catalysts with a unique morphology, designed to enhance reactant-surface contacts and maximize active site utilization. The developed nanoarchitectures show superior performances for ethanol oxidation in alkaline media. We reveal that Au decoration boosts MnO(2)catalytic activity by inducing pre-dissociation and pre-oxidation of the adsorbed ethanol molecules. This evidence validates our strategy as an effective route for the development of green electrocatalysts for efficient electrical-to-chemical energy conversion.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000562931300008 Publication Date 2020-07-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7488; 2050-7496 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 11.9 Times cited 16 Open Access OpenAccess
Notes (up) ; This work was financially supported by Padova University DOR 2016-2019 and P-DiSC #03BIRD2018-UNIPD OXYGENA projects, as well as by the INSTM Consortium (INSTMPD004 – NETTUNO), AMGA Foundation Mn4Energy project and Insubria University FAR2018. J. V. and D. K. acknowledge funding from the Flemish Government (Hercules), GOA project “Solarpaint” (Antwerp University) and European Union's H2020 programme under grant agreement no. 823717 ESTEEM3. The authors are grateful to Dr Gianluca Corr for skillful technical support. ; esteem3TA; esteem3reported Approved Most recent IF: 11.9; 2020 IF: 8.867
Call Number UA @ admin @ c:irua:171989 Serial 6506
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Author Wang, J.; Nguyen, M.D.; Gauquelin, N.; Verbeeck, J.; Do, M.T.; Koster, G.; Rijnders, G.; Houwman, E.
Title On the importance of the work function and electron carrier density of oxide electrodes for the functional properties of ferroelectric capacitors Type A1 Journal article
Year 2020 Publication Physica Status Solidi-Rapid Research Letters Abbreviated Journal Phys Status Solidi-R
Volume 14 Issue 14 Pages 1900520
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract It is important to understand the effect of the interfaces between the oxide electrode layers and the ferroelectric layer on the polarization response for optimizing the device performance of all-oxide ferroelectric devices. Herein, the effects of the oxide La0.07Ba0.93SnO3 (LBSO) as an electrode material in an PbZr0.52Ti0.48O3 (PZT) ferroelectric capacitor are compared with those of the more commonly used SrRuO3 (SRO) electrode. SRO (top)/PZT/SRO (bottom), SRO/PZT/LBSO, and SRO/PZT/2 nm SRO/LBSO devices are fabricated. Only marginal differences in crystalline properties, determined by X-ray diffraction and scanning transmission electron microscopy, are found. High-quality polarization loops are obtained, but with a much larger coercive field for the SRO/PZT/LBSO device. In contrast to the SRO/PZT/SRO device, the polarization decreases strongly with increasing field cycling. This fatigue problem can be remedied by inserting a 2 nm SRO layer between PZT and LBSO. It is argued that strongly increased charge injection into the PZT occurs at the bottom interface, because of the low PZT/LBSO interfacial barrier and the much lower carrier density in LBSO, as compared with that in SRO, causing a low dielectric constant, depleted layer in LBSO. The charge injection creates a trapped space charge in the PZT, causing the difference in fatigue behavior.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000506195600001 Publication Date 2019-12-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1862-6254 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.8 Times cited 6 Open Access OpenAccess
Notes (up) ; This work was supported by Nederlandse Organisatie voor Wetenschappelijk Onderzoek through grant no.13HTSM01. ; Approved Most recent IF: 2.8; 2020 IF: 3.032
Call Number UA @ admin @ c:irua:165681 Serial 6316
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Author O'Donnell, D.; Hassan, S.; Du, Y.; Gauquelin, N.; Krishnan, D.; Verbeeck, J.; Fan, R.; Steadman, P.; Bencok, P.; Dobrynin, A.N.
Title Etching induced formation of interfacial FeMn in IrMn/CoFe bilayers Type A1 Journal article
Year 2019 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 52 Issue 16 Pages 165002
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The effect of ion etching on exchange bias in IrMn3/Co70Fe30 bilayers is investigated. In spite of the reduction of saturation magnetization caused by the embedding of Tr from the capping layer into the Co70Fe30 layer during the etching process, the exchange bias in samples with the same thickness of the Co70Fe30 layer is reducing in proportion to the etching power. X-ray magnetic circular dichroism measurements revealed the emergence of an uncompensated Mn magnetization after etching, which is antiferromagnetically coupled to the ferromagnetic layer. This suggests etching induced formation of small interfacial FeMn regions which leads to the decrease of effective exchange coupling between ferromagnetic and antiferromagnetic layers.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000458524800001 Publication Date 2019-01-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727 ISBN Additional Links UA library record; WoS full record
Impact Factor 2.588 Times cited Open Access OpenAccess
Notes (up) ; This work was supported by Seagate Technology (Ireland). Beamline I10, Diamond Light Source, is acknowledged for provided beamtime. ; Approved Most recent IF: 2.588
Call Number UA @ admin @ c:irua:157458 Serial 5247
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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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Corporate Author Thesis
Publisher Place of Publication Editor
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 (up) ; 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 Groenendijk, D.J.; Autieri, C.; Girovsky, J.; Martinez-Velarte, M.C.; Manca, N.; Mattoni, G.; Monteiro, A.M.R.V.L.; Gauquelin, N.; Verbeeck, J.; Otte, A.F.; Gabay, M.; Picozzi, S.; Caviglia, A.D.
Title Spin-orbit semimetal SrIrO3 in the two-dimensional limit Type A1 Journal article
Year 2017 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 119 Issue 25 Pages 256403
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract <script type='text/javascript'>document.write(unpmarked('We investigate the thickness-dependent electronic properties of ultrathin SrIrO3 and discover a transition from a semimetallic to a correlated insulating state below 4 unit cells. Low-temperature magnetoconductance measurements show that spin fluctuations in the semimetallic state are significantly enhanced while approaching the transition point. The electronic properties are further studied by scanning tunneling spectroscopy, showing that 4 unit cell SrIrO(3)d is on the verge of a gap opening. Our density functional theory calculations reproduce the critical thickness of the transition and show that the opening of a gap in ultrathin SrIrO3 requires antiferromagnetic order.'));
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Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000418619100014 Publication Date 2017-12-22
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 79 Open Access OpenAccess
Notes (up) ; This work was supported by The Netherlands Organisation for Scientific Research (NWO/OCW) as part of the Frontiers of Nanoscience program (NanoFront), by the Dutch Foundation for Fundamental Research on Matter (FOM), and by the European Research Council under the European Union's H2020 programme/ERC Grant Agreement No. [677458]. The authors thank R. Claessen, P. Schutz, D. Di Sante, G. Sangiovanni, and A. Santander Syro for useful discussions. M. G. gratefully acknowledges support from the French National Research Agency (ANR) (Project LACUNES No. ANR-13-BS04-0006-01). C. A. and S. P. acknowledge financial support from Fondazione Cariplo via the project Magister (Project No. 2013-0726) and from CNR-SPIN via the Seed Project “CAMEO”. N. G. and J. V. acknowledge support from the GOA project “Solarpaint” of the University of Antwerp. The Qu-AntEM microscope was partly funded by the Hercules fund from the Flemish Government. ; Approved Most recent IF: 8.462
Call Number UA @ lucian @ c:irua:148510 Serial 4897
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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.
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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 (up) ; 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
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Author Lin, S.-C.; Kuo, C.-T.; Shao, Y.-C.; Chuang, Y.-D.; Geessinck, J.; Huijben, M.; Rueff, J.-P.; Graff, I.L.; Conti, G.; Peng, Y.; Bostwick, A.; Gullikson, E.; Nemsak, S.; Vailionis, A.; Gauquelin, N.; Verbeeck, J.; Ghiringhelli, G.; Schneider, C.M.; Fadley, C.S.
Title Two-dimensional electron systems in perovskite oxide heterostructures : role of the polarity-induced substitutional defects Type A1 Journal article
Year 2020 Publication Physical review materials Abbreviated Journal
Volume 4 Issue 11 Pages 115002
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The discovery of a two-dimensional electron system (2DES) at the interfaces of perovskite oxides such as LaAlO3 and SrTiO3 has motivated enormous efforts in engineering interfacial functionalities with this type of oxide heterostructures. However, the fundamental origins of the 2DES are still not understood, e.g., the microscopic mechanisms of coexisting interface conductivity and magnetism. Here we report a comprehensive spectroscopic investigation on the depth profile of 2DES-relevant Ti 3d interface carriers using depthand element-specific techniques like standing-wave excited photoemission and resonant inelastic scattering. We found that one type of Ti 3d interface carriers, which give rise to the 2DES are located within three unit cells from the n-type interface in the SrTiO3 layer. Unexpectedly, another type of interface carriers, which are polarity-induced Ti-on-Al antisite defects, reside in the first three unit cells of the opposing LaAlO3 layer (similar to 10 angstrom). Our findings provide a microscopic picture of how the localized and mobile Ti 3d interface carriers distribute across the interface and suggest that the 2DES and 2D magnetism at the LaAlO3/SrTiO3 interface have disparate explanations as originating from different types of interface carriers.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000592432200004 Publication Date 2020-11-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.4 Times cited 7 Open Access OpenAccess
Notes (up) ; We thank G. M. De Luca and L. Braicovich for discussions. Charles S. Fadley was deceased on August 1, 2019. We are grateful for his significant contributions to this work. We thank Advanced Light Source for the access to Beamline 8.0.3 (qRIXS) via Proposal No. 09892 and beamline 7.0.2 (MAESTRO) via Proposal No. RA-00291 that contributed to the results presented here. We thank synchrotron SOLEIL (via Proposal No. 99180118) for the access to Beamline GALAXIES. This work was supported by the U.S. Department of Energy (DOE) under Contract No. DE-AC02-05CH11231 (Advanced Light Source), and by DOE Contract No. DE-SC0014697 through the University of California, Davis (S.-C.L., C.-T.K, and C.S.F.), and from the Julich Research Center, Peter Grunberg Institute, PGI-6. I. L. G. wishes to thank Brazilian scientific agencies CNPQ (Project No. 200789/2017-1) and CAPES (CAPES-PrInt-UFPR) for their financial support. J.V. and N.G. acknowledge funding from the Geconcentreerde Onderzoekacties (GOA) project “Solarpaint” of the University of Antwerp and the European Union's horizon 2020 research and innovation program ES-TEEM3 under grant agreement no 823717. The Qu-Ant-EM microscope used in this study was partly funded by the Hercules fund from the Flemish Government. ; esteem3TA; esteem3reported Approved Most recent IF: 3.4; 2020 IF: NA
Call Number UA @ admin @ c:irua:174316 Serial 6713
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Author Yin, C.; Krishnan, D.; Gauquelin, N.; Verbeeck, J.; Aarts, J.
Title Controlling the interfacial conductance in LaAlO3/SrTiO3 in 90 degrees off-axis sputter deposition Type A1 Journal article
Year 2019 Publication Physical review materials Abbreviated Journal
Volume 3 Issue 3 Pages 034002
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report on the fabrication of conducting interfaces between LaAlO3 and SrTiO3 by 90 degrees off-axis sputtering in an Ar atmosphere. At a growth pressure of 0.04 mbar the interface is metallic, with a carrier density of the order of 1 x 10(13) cm(-2) at 3 K. By increasing the growth pressure, we observe an increase of the out-of-plane lattice constants of the LaAlO3 films while the in-plane lattice constants do not change. Also, the low-temperature sheet resistance increases with increasing growth pressure, leading to an insulating interface when the growth pressure reaches 0.10 mbar. We attribute the structural variations to an increase of the La/Al ratio, which also explains the transition from metallic behavior to insulating behavior of the interfaces. Our research shows that the control which is furnished by the Ar pressure makes sputtering as versatile a process as pulsed laser deposition, and emphasizes the key role of the cation stoichiometry of LaAlO3 in the formation of the conducting interface.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000461077100002 Publication Date 2019-03-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.926 Times cited 4 Open Access Not_Open_Access
Notes (up) ; We thank Nikita Lebedev, Aymen Ben Hamida, and Prateek Kumar for useful discussions and Giordano Mattoni, Jun Wang, Vincent Joly, and Hozanna Miro for their technical assistance. We also thank Jean-Marc Triscone and his group for sharing their design of the sputtering system with us. This work is part of the FOM research programme DESCO with Project No. 149, which is (partly) financed by the Netherlands Organisation for Scientific Research (NWO). C.Y. is supported by China Scholarship Council (CSC) with Grant No. 201508110214. N.G., D.K., and J.V. acknowledge financial support from the GOA project “Solarpaint” of the University of Antwerp. ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:158547 Serial 5243
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Author Zhang, G.; Zhou, Y.; Korneychuk, S.; Samuely, T.; Liu, L.; May, P.W.; Xu, Z.; Onufriienko, O.; Zhang, X.; Verbeeck, J.; Samuely, P.; Moshchalkov, V.V.; Yang, Z.; Rubahn, H.-G.
Title Superconductor-insulator transition driven by pressure-tuned intergrain coupling in nanodiamond films Type A1 Journal article
Year 2019 Publication Physical review materials Abbreviated Journal
Volume 3 Issue 3 Pages 034801
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report on the pressure-driven superconductor-insulator transition in heavily boron-doped nanodiamond films. By systematically increasing the pressure, we suppress the Josephson coupling between the superconducting nanodiamond grains. The diminished intergrain coupling gives rise to an overall insulating state in the films, which is interpreted in the framework of a parallel-series circuit model to be the result of bosonic insulators with preserved localized intragrain superconducting order parameters. Our investigation opens up perspectives for the application of high pressure in research on quantum confinement and coherence. Our data unveil the percolative nature of the electrical transport in nanodiamond films, and highlight the essential role of grain boundaries in determining the electronic properties of this material.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000460684600002 Publication Date 2019-03-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.926 Times cited 5 Open Access Not_Open_Access
Notes (up) ; Y.Z. and Z.Y. acknowledge support from the National Key Research and Development Program of China (Grants No. 2018YFA0305700 and No. 2016YFA0401804), the National Natural Science Foundation of China (Grants No. 11574323, No. 11704387, and No. U1632275), the Natural Science Foundation of Anhui Province (Grants No. 1708085QA19 and No. 1808085MA06), and the Director's Fund of Hefei Institutes of Physical Science, Chinese Academy of Sciences (YZJJ201621). J.V. and S.K. acknowledge funding from the GOA project “Solarpaint” of the University of Antwerp, and thank the FWO (Research Foundation-Flanders) for financial support under Contract No. G.0044.13N “Charge ordering”. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. T.S., O.O., and P.S. are supported by APVV-0036-11, APVV-0605-14, VEGA 1/0409/15, VEGA 2/0149/16, and EU ERDF-ITMS 26220120005. L.L. acknowledges the financial support of a FWO postdoctoral research fellowship (12V4419N) and the KU Leuven C1 project OPTIPROBE (C14/16/ 063). ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:158561 Serial 5260
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Author Janssens, K.; van der Snickt, G.; Vanmeert, F.; Legrand, S.; Nuyts, G.; Alfeld, M.; Monico, L.; Anaf, W.; de Nolf, W.; Vermeulen, M.; Verbeeck, J.; De Wael, K.
Title Non-invasive and non-destructive examination of artistic pigments, paints, and paintings by means of X-Ray methods Type A1 Journal article
Year 2016 Publication Topics in Current Chemistry Abbreviated Journal Topics Curr Chem
Volume 374 Issue 374 Pages 81
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Recent studies are concisely reviewed, in which X-ray beams of (sub)micrometre to millimetre dimensions have been used for non-destructive analysis and characterization of pigments, minute paint samples, and/or entire paintings from the seventeenth to the early twentieth century painters. The overview presented encompasses the use of laboratory and synchrotron radiation-based instrumentation and deals with the use of several variants of X-ray fluorescence (XRF) as a method of elemental analysis and imaging, as well as with the combined use of X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS). Microscopic XRF is a variant of the method that is well suited to visualize the elemental distribution of key elements, mostly metals, present in paint multi-layers, on the length scale from 1 to 100 μm inside micro-samples taken from paintings. In the context of the characterization of artists pigments subjected to natural degradation, the use of methods limited to elemental analysis or imaging usually is not sufficient to elucidate the chemical transformations that have taken place. However, at synchrotron facilities, combinations of μ-XRF with related methods such as μ-XAS and μ-XRD have proven themselves to be very suitable for such studies. Their use is often combined with microscopic Fourier transform infra-red spectroscopy and/or Raman microscopy since these methods deliver complementary information of high molecular specificity at more or less the same length scale as the X-ray microprobe techniques. Since microscopic investigation of a relatively limited number of minute paint samples, taken from a given work of art, may not yield representative information about the entire artefact, several methods for macroscopic, non-invasive imaging have recently been developed. Those based on XRF scanning and full-field hyperspectral imaging appear very promising; some recent published results are discussed.
Address
Corporate Author Thesis
Publisher Springer international publishing ag Place of Publication Cham Editor
Language Wos 000391178900006 Publication Date 2016-11-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2365-0869;2364-8961; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.033 Times cited 50 Open Access
Notes (up) ; ; Approved Most recent IF: 4.033
Call Number UA @ lucian @ c:irua:139930UA @ admin @ c:irua:139930 Serial 4443
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Author Annys, A.; Jannis, D.; Verbeeck, J.; Annys, A.; Jannis, D.; Verbeeck, J.
Title Deep learning for automated materials characterisation in core-loss electron energy loss spectroscopy Type A1 Journal article
Year 2023 Publication Scientific reports Abbreviated Journal
Volume 13 Issue 1 Pages 13724
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Electron energy loss spectroscopy (EELS) is a well established technique in electron microscopy that yields information on the elemental content of a sample in a very direct manner. One of the persisting limitations of EELS is the requirement for manual identification of core-loss edges and their corresponding elements. This can be especially bothersome in spectrum imaging, where a large amount of spectra are recorded when spatially scanning over a sample area. This paper introduces a synthetic dataset with 736,000 labeled EELS spectra, computed from available generalized oscillator strength tables, that represents 107 K, L, M or N core-loss edges and 80 chemical elements. Generic lifetime broadened peaks are used to mimic the fine structure due to band structure effects present in experimental core-loss edges. The proposed dataset is used to train and evaluate a series of neural network architectures, being a multilayer perceptron, a convolutional neural network, a U-Net, a residual neural network, a vision transformer and a compact convolutional transformer. An ensemble of neural networks is used to further increase performance. The ensemble network is used to demonstrate fully automated elemental mapping in a spectrum image, both by directly mapping the predicted elemental content and by using the predicted content as input for a physical model-based mapping.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001052937600046 Publication Date 2023-08-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record
Impact Factor 4.6 Times cited Open Access OpenAccess
Notes (up) A.A. would like to acknowledge the resources and services used in this work provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government. J.V. acknowledges the IMPRESS project. The IMPRESS project has received funding from the HORIZON EUROPE framework program for research and innovation under grant agreement n. 101094299. Approved Most recent IF: 4.6; 2023 IF: 4.259
Call Number UA @ admin @ c:irua:198647 Serial 8846
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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.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000375329200043 Publication Date 2016-03-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 40 Open Access
Notes (up) 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 Béché, A.; Winkler, R.; Plank, H.; Hofer, F.; Verbeeck, J.
Title Focused electron beam induced deposition as a tool to create electron vortices Type A1 Journal article
Year 2015 Publication Micron Abbreviated Journal Micron
Volume 80 Issue 80 Pages 34-38
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Focused electron beam induced deposition (FEBID) is a microscopic technique that allows geometrically controlled material deposition with very high spatial resolution. This technique was used to create a spiral aperture capable of generating electron vortex beams in a transmission electron microscope (TEM). The vortex was then fully characterized using different TEM techniques, estimating the average orbital angular momentum to be approximately 0.8variant Planck's over 2pi per electron with almost 60% of the beam ending up in the l=1 state.
Address EMAT, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000366770100006 Publication Date 2015-09-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0968-4328; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.98 Times cited 21 Open Access
Notes (up) 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., R.W., H.P. and F.H. acknowledge financial support from the European Union under the 7th Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative (Reference No. 312483 ESTEEM2). R.W and H.P also acknowledge financial support by the COST action CELINA (Nr. CM1301) and the EUROSTARS project TRIPLE-S (Nr. E!8213). The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government.; esteem2jra3 ECASJO; Approved Most recent IF: 1.98; 2015 IF: 1.988
Call Number c:irua:129203 c:irua:129203UA @ admin @ c:irua:129203 Serial 3946
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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 (up) 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 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.
Address
Corporate Author Thesis
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 (up) 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 Turner, S.; Verbeeck, J.; Ramezanipour, F.; Greedan, J.E.; Van Tendeloo, G.; Botton, G.A.
Title Atomic resolution coordination mapping in Ca2FeCoO5 brownmillerite by spatially resolved electron energy-loss spectroscopy Type A1 Journal article
Year 2012 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 24 Issue 10 Pages 1904-1909
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Using a combination of high-angle annular dark field scanning transmission electron microscopy and atomically resolved electron energy-loss spectroscopy at high energy resolution in an aberration-corrected electron microscope, we demonstrate the capability of coordination mapping in complex oxides. Brownmillerite compound Ca2FeCoO5, consisting of repetitive octahedral and tetrahedral coordination layers with Fe and Co in a fixed 3+ valency, is selected to demonstrate the principle of atomic resolution coordination mapping. Analysis of the Co-L2,3 and the Fe-L2,3 edges shows small variations in the fine structure that can be specifically attributed to Co/Fe in tetrahedral or in octahedral coordination. Using internal reference spectra, we show that the coordination of the Fe and Co atoms in the compound can be mapped at atomic resolution.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000304237500024 Publication Date 2012-04-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 33 Open Access
Notes (up) A.M. Abakumov is thanked for fruitful discussions. S.T. gratefully acknowledges the Fund for Scientific Research Flanders (FWO). J.E.G. and GAB. acknowledge the support of the NSERC of Canada through Discovery Grants. The Canadian Centre for Electron Microscopy is a National Facility supported by NSERC and McMaster University and was funded by the Canada Foundation for Innovation and the Ontario Government. Part of this work was supported by funding from the European Research Council under the FP7, ERC Grant N 246791 COUNTATOMS and ERC Starting Grant N 278510 VORTEX. The EMAT microscope is partially funded by the Hercules fund of the Flemish Government. ECASJO_; Approved Most recent IF: 9.466; 2012 IF: 8.238
Call Number UA @ lucian @ c:irua:98379UA @ admin @ c:irua:98379 Serial 175
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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.
Address
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 (up) 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 Velazco, A.; Béché, A.; Jannis, D.; Verbeeck, J.
Title Reducing electron beam damage through alternative STEM scanning strategies, Part I: Experimental findings Type A1 Journal article
Year 2022 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 232 Issue Pages 113398
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The highly energetic electrons in a transmission electron microscope (TEM) can alter or even completely destroy the structure of samples before sufficient information can be obtained. This is especially problematic in the case of zeolites, organic and biological materials. As this effect depends on both the electron beam and the sample and can involve multiple damage pathways, its study remained difficult and is plagued with irreproducibility issues, circumstantial evidence, rumors, and a general lack of solid data. Here we take on the experimental challenge to investigate the role of the STEM scan pattern on the damage behavior of a commercially available zeolite sample with the clear aim to make our observations as reproducible as possible. We make use of a freely programmable scan engine that gives full control over the tempospatial distribution of the electron probe on the sample and we use its flexibility to obtain multiple repeated experiments under identical conditions comparing the difference in beam damage between a conventional raster scan pattern and a newly proposed interleaved scan pattern that provides exactly the same dose and dose rate and visits exactly the same scan points. We observe a significant difference in beam damage for both patterns with up to 11 % reduction in damage (measured from mass loss). These observations demonstrate without doubt that electron dose, dose rate and acceleration voltage are not the only parameters affecting beam damage in (S)TEM experiments and invite the community to rethink beam damage as an unavoidable consequence of applied electron dose.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000714819200002 Publication Date 2021-10-02
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 2.2 Times cited 18 Open Access OpenAccess
Notes (up) A.V., D.J., A.B. and J.V. acknowledge funding from FWO project G093417N (’Compressed sensing enabling low dose imaging in transmission electron microscopy’) and G042920N (’Coincident event detection for advanced spectroscopy in transmission electron microscopy’). This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 823717 ESTEEM3. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. J.V. acknowledges funding from GOA project “Solarpaint” of the University of Antwerp.; JRA; reported Approved Most recent IF: 2.2
Call Number EMAT @ emat @c:irua:183282 Serial 6818
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Author Bliokh, K.Y.; Ivanov, I.P.; Guzzinati, G.; Clark, L.; Van Boxem, R.; Béché, A.; Juchtmans, R.; Alonso, M.A.; Schattschneider, P.; Nori, F.; Verbeeck, J.
Title Theory and applications of free-electron vortex states Type A1 Journal article
Year 2017 Publication Physics reports Abbreviated Journal Phys Rep
Volume 690 Issue 690 Pages 1-70
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Both classical and quantum waves can form vortices: with helical phase fronts and azimuthal current densities. These features determine the intrinsic orbital angular momentum carried by localized vortex states. In the past 25 years, optical vortex beams have become an inherent part of modern optics, with many remarkable achievements and applications. In the past decade, it has been realized and demonstrated that such vortex beams or wavepackets can also appear in free electron waves, in particular, in electron microscopy. Interest in free-electron vortex states quickly spread over different areas of physics: from basic aspects of quantum mechanics, via applications for fine probing of matter (including individual atoms), to high-energy particle collision and radiation processes. Here we provide a comprehensive review of theoretical and experimental studies in this emerging field of research. We describe the main properties of electron vortex states, experimental achievements and possible applications within transmission electron microscopy, as well as the possible role of vortex electrons in relativistic and high-energy processes. We aim to provide a balanced description including a pedagogical introduction, solid theoretical basis, and a wide range of practical details. Special attention is paid to translate theoretical insights into suggestions for future experiments, in electron microscopy and beyond, in any situation where free electrons occur.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000406169900001 Publication Date 2017-05-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-1573 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 17.425 Times cited 210 Open Access OpenAccess
Notes (up) AFOSR, FA9550-14-1-0040 ; CREST, JPMJCR1676 ; Portuguese Fundação para a Ciência e a Tecnologia (FCT), IF/00989/2014/CP1214/CT0004 ; Austrian Science Fund, I543-N20 ; ERC, 278510 VORTEX ; We acknowledge discussions with Mark R. Dennis and Andrei Afanasev. This work was supported by the RIKEN Interdisciplinary Theoretical Science Research Group (iTHES) Project, the Multi-University Research Initiative (MURI) Center for Dynamic Magneto-Optics via the Air Force Office of Scientific Research (AFOSR) (Grant No. FA9550-14-1-0040), Grant-in-Aid for Scientific Research (A), Core Research for Evolutionary Science and Technology (CREST), the John Templeton Foundation, the Australian Research Council, the Portuguese Funda¸c˜ao para a Ciˆencia e a Tecnologia (FCT) (contract IF/00989/2014/CP1214/CT0004 under the IF2014 Program), contracts UID/FIS/00777/2013 and CERN/FIS-NUC/0010/2015 (partially funded through POCTI, COMPETE, QREN, and the European Union), Austrian Science Fund Grant No. I543-N20, the European Research Council under the 7th Framework Program (FP7) (ERC Starting Grant No. 278510 VORTEX), and FWO PhD Fellowship grants (Aspirant Fonds Wetenschappelijk OnderzoekVlaanderen). Approved Most recent IF: 17.425
Call Number EMAT @ emat @ c:irua:143262 Serial 4574
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Author Samal, D.; Gauquelin, N.; Takamura, Y.; Lobato, I.; Arenholz, E.; Van Aert, S.; Huijben, M.; Zhong, Z.; Verbeeck, J.; Van Tendeloo, G.; Koster, G.
Title Unusual structural rearrangement and superconductivity in infinite layer cuprate superlattices Type A1 Journal article
Year 2023 Publication Physical review materials Abbreviated Journal
Volume 7 Issue 5 Pages 054803
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001041792100007 Publication Date 2023-05-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record
Impact Factor 3.4 Times cited Open Access OpenAccess
Notes (up) Air Force Office of Scientific Research; European Office of Aerospace Research and Development, FA8655-10-1-3077 ; Office of Science, DE-AC02-05CH11231 ; National Science Foundation, DMR-1745450 ; Seventh Framework Programme, 278510 ; Bijzonder Onderzoeksfonds UGent; Approved Most recent IF: 3.4; 2023 IF: NA
Call Number EMAT @ emat @c:irua:196973 Serial 8790
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Author Vega Ibañez, F.; Béché, A.; Verbeeck, J.
Title Can a programmable phase plate serve as an aberration corrector in the transmission electron microscope (TEM)? Type A1 Journal article
Year 2022 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal
Volume Issue Pages Pii S1431927622012260-10
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Current progress in programmable electrostatic phase plates raises questions about their usefulness for specific applications. Here, we explore different designs for such phase plates with the specific goal of correcting spherical aberration in the transmission electron microscope (TEM). We numerically investigate whether a phase plate could provide down to 1 angstrom ngstrom spatial resolution on a conventional uncorrected TEM. Different design aspects (fill factor, pixel pattern, symmetry) were evaluated to understand their effect on the electron probe size and current density. Some proposed designs show a probe size () down to 0.66 angstrom, proving that it should be possible to correct spherical aberration well past the 1 angstrom limit using a programmable phase plate consisting of an array of electrostatic phase-shifting elements.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000849975400001 Publication Date 2022-09-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1431-9276 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.8 Times cited 3 Open Access OpenAccess
Notes (up) All authors acknowledge funding from the Flemish Research Fund under contract G042820N “Exploring adaptive optics in transmission electron microscopy”. J.V. acknowledges funding from the European Union’s Horizon 2020 Research Infrastructure – Integrating Activities for Advanced Communities under grant agreement No 823717 – ESTEEM3 and from the University of Antwerp through a TOP BOF project.; esteem3reported; esteem3jra Approved Most recent IF: 2.8
Call Number UA @ admin @ c:irua:190627 Serial 7134
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Author Yu, C.-P.; Friedrich, T.; Jannis, D.; Van Aert, S.; Verbeeck, J.
Title Real-Time Integration Center of Mass (riCOM) Reconstruction for 4D STEM Type A1 Journal article
Year 2022 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal
Volume Issue Pages 1-12
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract A real-time image reconstruction method for scanning transmission electron microscopy (STEM) is proposed. With an algorithm requiring only the center of mass of the diffraction pattern at one probe position at a time, it is able to update the resulting image each time a new probe position is visited without storing any intermediate diffraction patterns. The results show clear features at high spatial frequency, such as atomic column positions. It is also demonstrated that some common post-processing methods, such as band-pass filtering, can be directly integrated in the real-time processing flow. Compared with other reconstruction methods, the proposed method produces high-quality reconstructions with good noise robustness at extremely low memory and computational requirements. An efficient, interactive open source implementation of the concept is further presented, which is compatible with frame-based, as well as event-based camera/file types. This method provides the attractive feature of immediate feedback that microscope operators have become used to, for example, conventional high-angle annular dark field STEM imaging, allowing for rapid decision-making and fine-tuning to obtain the best possible images for beam-sensitive samples at the lowest possible dose.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000792176100001 Publication Date 2022-04-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1431-9276 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.8 Times cited 7 Open Access OpenAccess
Notes (up) Bijzonder Onderzoeksfonds UGent; H2020 European Research Council, 770887 ; H2020 European Research Council, 823717 ; H2020 European Research Council, ESTEEM3 / 823717 ; H2020 European Research Council, PICOMETRICS / 770887 ; Fonds Wetenschappelijk Onderzoek, 30489208 ; Herculesstichting; esteem3reported; esteem3jra Approved Most recent IF: 2.8
Call Number EMAT @ emat @c:irua:188538 Serial 7068
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Author Das, P.P.; Guzzinati, G.; Coll, C.; Gomez Perez, A.; Nicolopoulos, S.; Estrade, S.; Peiro, F.; Verbeeck, J.; Zompra, A.A.; Galanis, A.S.
Title Reliable Characterization of Organic & Pharmaceutical Compounds with High Resolution Monochromated EEL Spectroscopy Type A1 Journal article
Year 2020 Publication Polymers Abbreviated Journal Polymers-Basel
Volume 12 Issue 7 Pages 1434
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Organic and biological compounds (especially those related to the pharmaceutical industry) have always been of great interest for researchers due to their importance for the development of new drugs to diagnose, cure, treat or prevent disease. As many new API (active pharmaceutical ingredients) and their polymorphs are in nanocrystalline or in amorphous form blended with amorphous polymeric matrix (known as amorphous solid dispersion—ASD), their structural identification and characterization at nm scale with conventional X-Ray/Raman/IR techniques becomes difficult. During any API synthesis/production or in the formulated drug product, impurities must be identified and characterized. Electron energy loss spectroscopy (EELS) at high energy resolution by transmission electron microscope (TEM) is expected to be a promising technique to screen and identify the different (organic) compounds used in a typical pharmaceutical or biological system and to detect any impurities present, if any, during the synthesis or formulation process. In this work, we propose the use of monochromated TEM-EELS, to analyze selected peptides and organic compounds and their polymorphs. In order to validate EELS for fingerprinting (in low loss/optical region) and by further correlation with advanced DFT, simulations were utilized.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000556786700001 Publication Date 2020-06-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2073-4360 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.364 Times cited 6 Open Access OpenAccess
Notes (up) C.C., F.P., S.E. acknowledges the Spanish government for projects MAT2016-79455-P, Research Network RED2018-102609-T and the FPI (BES-2017-080045) grant of Ministerio de Ciència, Innovación y Universidades. G.G. acknowledges support from a postdoctoral fellowship grant from the Fonds Wetenschappelijk Onderzoek—Vlaanderen (FWO). P.P.D., A.G.P., S.N. gratefully acknowledge much helpful discussion on EELS study for organic compounds with Dr. Andrey Chuvilin (CIC NANOGUNE, Donostia—San Sebastian, Spain). The authors also acknowledge Raúl Arenal (University de Zaragoza, Spain) for useful discussion on EELS. The authors acknowledge also Ulises Julio Amador Elizondo (Universidad CEU San Pablo, Spain) for kindly provide the aripiprazole and piroxicam samples for EELS study.; EUSMI_TA; Approved Most recent IF: NA
Call Number EMAT @ emat @c:irua:170603 Serial 6400
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Author Schattschneider, P.; Stoeger-Pollach, M.; Verbeeck, J.
Title Novel vortex generator and mode converter for electron beams Type A1 Journal article
Year 2012 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 109 Issue 8 Pages 084801-1
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A mode converter for electron vortex beams is described. Numerical simulations, confirmed by experiment, show that the converter transforms a vortex beam with a topological charge m = +/- 1 into beams closely resembling Hermite-Gaussian HG(10) and HG(01) modes. The converter can be used as a mode discriminator or filter for electron vortex beams. Combining the converter with a phase plate turns a plane wave into modes with topological charge m = +/- 1. This combination serves as a generator of electron vortex beams of high brilliance.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000307790900004 Publication Date 2012-08-22
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 74 Open Access
Notes (up) Countatoms; Vortex ECASJO_; Approved Most recent IF: 8.462; 2012 IF: 7.943
Call Number UA @ lucian @ c:irua:101103UA @ admin @ c:irua:101103 Serial 2384
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Author Schattschneider, P.; Löffler, S.; Verbeeck, J.
Title Comment on “Quantized orbital angular momentum transfer and magnetic dichroism in the interaction of electron vortices with matter” Type Editorial
Year 2013 Publication Physical review letters Abbreviated Journal Phys Rev Lett
Volume 110 Issue 18 Pages 189501-189502
Keywords Editorial; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000319019300019 Publication Date 2013-05-02
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 8 Open Access
Notes (up) Countatoms; Vortex; Esteem2; esteem2jra3 ECASJO; Approved Most recent IF: 8.462; 2013 IF: 7.728
Call Number UA @ lucian @ c:irua:109014UA @ admin @ c:irua:109014 Serial 410
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