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| Author | Mary Joy, R.; Pobedinskas, P.; Baule, N.; Bai, S.; Jannis, D.; Gauquelin, N.; Pinault-Thaury, M.-A.; Jomard, F.; Sankaran, K.J.; Rouzbahani, R.; Lloret, F.; Desta, D.; D’Haen, J.; Verbeeck, J.; Becker, M.F.; Haenen, K. | ||||
| Title | The effect of microstructure and film composition on the mechanical properties of linear antenna CVD diamond thin films | Type | A1 Journal article | ||
| Year | 2024 | Publication | Acta materialia | Abbreviated Journal | Acta Materialia |
| Volume | 264 | Issue | Pages | 119548 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | This study reports the impact of film microstructure and composition on the Young’s modulus and residual stress in nanocrystalline diamond (NCD) thin films ( thick) grown on silicon substrates using a linear antenna microwave plasma-enhanced chemical vapor deposition (CVD) system. Combining laser acoustic wave spectroscopy to determine the elastic properties with simple wafer curvature measurements, a straightforward method to determine the intrinsic stress in NCD films is presented. Two deposition parameters are varied: (1) the substrate temperature from 400 °C to 900 °C, and (2) the [P]/[C] ratio from 0 ppm to 8090 ppm in the H2/CH4/CO2/PH3 diamond CVD plasma. The introduction of PH3 induces a transition in the morphology of the diamond film, shifting from NCD with larger grains to ultra-NCD with a smaller grain size, concurrently resulting in a decrease in Young’s modulus. Results show that the highest Young’s modulus of (113050) GPa for the undoped NCD deposited at 800 °C is comparable to single crystal diamond, indicating that NCD with excellent mechanical properties is achievable with our process for thin diamond films. Based on the film stress results, we propose the origins of tensile intrinsic stress in the diamond films. In NCD, the tensile intrinsic stress is attributed to larger grain size, while in ultra-NCD films the tensile intrinsic stress is due to grain boundaries and impurities. | ||||
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| Language | Wos | 001126632800001 | Publication Date | 2023-11-23 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1359-6454 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 9.4 | Times cited | Open Access  |
Not_Open_Access | |
| Notes | This work was financially supported by the Special Research Fund (BOF) via Methusalem NANO network, the Research Foundation – Flanders (FWO) via Project G0D4920N, and the CORNET project nr 263-EN “ULTRAHARD: Ultrahard optical diamond coatings” (2020–2021). | Approved | Most recent IF: 9.4; 2024 IF: 5.301 | ||
| Call Number | EMAT @ emat @c:irua:202169 | Serial | 8989 | ||
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| Author | Van den Broek, W.; Jannis, D.; Verbeeck, J. | ||||
| Title | Convexity constraints on linear background models for electron energy-loss spectra | Type | A1 Journal Article | ||
| Year | 2023 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 254 | Issue | Pages | 113830 | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | In this paper convexity constraints are derived for a background model of electron energy loss spectra (EELS) that is linear in the fitting parameters. The model outperforms a power-law both on experimental and simulated backgrounds, especially for wide energy ranges, and thus improves elemental quantification results. Owing to the model’s linearity, the constraints can be imposed through fitting by quadratic programming. This has important advantages over conventional nonlinear power-law fitting such as high speed and a guaranteed unique solution without need for initial parameters. As such, the need for user input is significantly reduced, which is essential for unsupervised treatment of large datasets. This is demonstrated on a demanding spectrum image of a semiconductor device sample with a high number of elements over a wide energy range. | ||||
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| Language | Wos | Publication Date | 2023-08-15 | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record | |
| Impact Factor | 2.2 | Times cited | Open Access |
Not_Open_Access | |
| Notes | ECSEL, 875999 ; Horizon 2020; Horizon 2020 Framework Programme; Electronic Components and Systems for European Leadership; | Approved | Most recent IF: 2.2; 2023 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:200588 | Serial | 8961 | ||
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| Author | Zhang, Z.; Lobato, I.; Brown, H.; Jannis, D.; Verbeeck, J.; Van Aert, S.; Nellist, P. | ||||
| Title | Generalised oscillator strength for core-shell electron excitation by fast electrons based on Dirac solutions | Type | Dataset | ||
| Year | 2023 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
| Keywords | Dataset; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Inelastic excitation as exploited in Electron Energy Loss Spectroscopy (EELS) contains a rich source of information that is revealed in the scattering process. To accurately quantify core-loss EELS, it is common practice to fit the observed spectrum with scattering cross-sections calculated using experimental parameters and a Generalized Oscillator Strength (GOS) database [1]. The GOS is computed using Fermi’s Golden Rule and orbitals of bound and excited states. Previously, the GOS was based on Hartree-Fock solutions [2], but more recently Density Functional Theory (DFT) has been used [3]. In this work, we have chosen to use the Dirac equation to incorporate relativistic effects and have performed calculations using Flexible Atomic Code (FAC) [4]. This repository contains a tabulated GOS database based on Dirac solutions for computing double differential cross-sections under experimental conditions. We hope the Dirac-based GOS database can benefit the EELS community for both academic use and industry integration. Database Details: – Covers all elements (Z: 1-108) and all edges – Large energy range: 0.01 – 4000 eV – Large momentum range: 0.05 -50 Å-1 – Fine log sampling: 128 points for energy and 256 points for momentum – Data format: GOSH [3] Calculation Details: – Single atoms only; solid-state effects are not considered – Unoccupied states before continuum states of ionization are not considered; no fine structure – Plane Wave Born Approximation – Frozen Core Approximation is employed; electrostatic potential remains unchanged for orthogonal states when – core-shell electron is excited – Self-consistent Dirac–Fock–Slater iteration is used for Dirac calculations; Local Density Approximation is assumed for electron exchange interactions; continuum states are normalized against asymptotic form at large distances – Both large and small component contributions of Dirac solutions are included in GOS – Final state contributions are included until the contribution of the previous three states falls below 0.1%. A convergence log is provided for reference. Version 1.1 release note: – Update to be consistent with GOSH data format [3], all the edges are now within a single hdf5 file. A notable change in particular, the sampling in momentum is in 1/m, instead of previously in 1/Å. Great thanks to Gulio Guzzinati for his suggestions and sending conversion script. Version 1.2 release note: – Add “File Type / File version” information [1] Verbeeck, J., and S. Van Aert. Ultramicroscopy 101.2-4 (2004): 207-224. [2] Leapman, R. D., P. Rez, and D. F. Mayers. The Journal of Chemical Physics 72.2 (1980): 1232-1243. [3] Segger, L, Guzzinati, G, & Kohl, H. Zenodo (2023). doi:10.5281/zenodo.7645765 [4] Gu, M. F. Canadian Journal of Physics 86(5) (2008): 675-689. | ||||
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| Language | Wos | Publication Date | |||
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| ISSN | ISBN | Additional Links | UA library record | ||
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| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ admin @ c:irua:203392 | Serial | 9042 | ||
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| Author | Hugenschmidt, M.; Jannis, D.; Kadu, A.A.; Grünewald, L.; De Marchi, S.; Perez-Juste, J.; Verbeeck, J.; Van Aert, S.; Bals, S. | ||||
| Title | Low-dose 4D-STEM tomography for beam-sensitive nanocomposites | Type | A1 Journal article | ||
| Year | 2023 | Publication | ACS materials letters | Abbreviated Journal | |
| Volume | 6 | Issue | 1 | Pages | 165-173 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Electron tomography is essential for investigating the three-dimensional (3D) structure of nanomaterials. However, many of these materials, such as metal-organic frameworks (MOFs), are extremely sensitive to electron radiation, making it difficult to acquire a series of projection images for electron tomography without inducing electron-beam damage. Another significant challenge is the high contrast in high-angle annular dark field scanning transmission electron microscopy that can be expected for nanocomposites composed of a metal nanoparticle and an MOF. This strong contrast leads to so-called metal artifacts in the 3D reconstruction. To overcome these limitations, we here present low-dose electron tomography based on four-dimensional scanning transmission electron microscopy (4D-STEM) data sets, collected using an ultrafast and highly sensitive direct electron detector. As a proof of concept, we demonstrate the applicability of the method for an Au nanostar embedded in a ZIF-8 MOF, which is of great interest for applications in various fields, including drug delivery. | ||||
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| Language | Wos | 001141178500001 | Publication Date | 2023-12-11 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 2639-4979 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | Times cited | Open Access |
Not_Open_Access | ||
| Notes | This work was supported by the European Research Council (Grant 815128 REALNANO to S.B., Grant 770887 PICOMETRICS to S.V.A.). J.P.-J. and S.M. acknowledge financial support from the MCIN/AEI/10.13039/501100011033 (Grants No. PID2019-108954RB-I00) and EU Horizon 2020 research and innovation program under grant agreement no. 883390 (SERSing). J.V., S.B., S.V.A., and L.G. acknowledge funding from the Flemish government (iBOF-21-085 PERsist). | Approved | Most recent IF: NA | ||
| Call Number | UA @ admin @ c:irua:202771 | Serial | 9053 | ||
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| Author | Grünewald, L.; Chezganov, D.; De Meyer, R.; Orekhov, A.; Van Aert, S.; Bogaerts, A.; Bals, S.; Verbeeck, J. | ||||
| Title | Supplementary Information for “In-situ Plasma Studies using a Direct Current Microplasma in a Scanning Electron Microscope” | Type | Dataset | ||
| Year | 2023 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
| Keywords | Dataset; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | Supplementary information for the article “In-situ Plasma Studies using a Direct Current Microplasma in a Scanning Electron Microscope” containing the videos of in-situ SEM imaging (mp4 files), raw data/images, and Jupyter notebooks (ipynb files) for data treatment and plots. Link to the preprint: https://doi.org/10.48550/arXiv.2308.15123 Explanation of the data files can be found in the Information.pdf file. The Videos folder contains the in-situ SEM image series mentioned in the paper. If there are any questions/bugs, feel free to contact me at lukas.grunewaldatuantwerpen.be | ||||
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| ISSN | ISBN | Additional Links | UA library record | ||
| Impact Factor | Times cited | Open Access |
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| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ admin @ c:irua:203389 | Serial | 9100 | ||
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| Author | Verbeeck, J.; Béché, A.; Müller-Caspary, K.; Guzzinati, G.; Luong, M.A.; Den Hertog, M. | ||||
| Title | Demonstration of a 2 × 2 programmable phase plate for electrons | Type | A1 Journal article | ||
| Year | 2018 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 190 | Issue | Pages | 58-65 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | First results on the experimental realisation of a 2 × 2 programmable phase plate for electrons are presented. The design consists of an array of electrostatic elements that influence the phase of electron waves passing through 4 separately controllable aperture holes. This functionality is demonstrated in a conventional transmission electron microscope operating at 300 kV and results are in very close agreement with theoretical predictions. The dynamic creation of a set of electron probes with different phase symmetry is demonstrated, thereby bringing adaptive optics in TEM one step closer to reality. The limitations of the current design and how to overcome these in the future are discussed. Simulations show how further evolved versions of the current proof of concept might open new and exciting application prospects for beam shaping and aberration correction. | ||||
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| Language | Wos | 000432868800007 | Publication Date | 2018-04-18 | |
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| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 73 | Open Access |
Not_Open_Access: Available from 19.04.2020 |
| Notes | J.V. and A.B. acknowledge funding from the Fund for Scientific Research Flanders FWO project G093417N and the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX and ERC proof of concept project DLV-789598 ADAPTEM. The Qu-Ant-EM microscope used in this work was partly funded by the Hercules fund from the Flemish Government. MdH acknowledges financial support from the ANRCOSMOS (ANR-12-JS10-0002). MdH and ML acknowledge funding from the Laboratoire d’excellence LANEF in Grenoble (ANR-10-LABX-51-01). | Approved | Most recent IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:150459UA @ admin @ c:irua:150459 | Serial | 4920 | ||
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| Author | Godet, M.; Vergès-Belmin, V.; Gauquelin, N.; Saheb, M.; Monnier, J.; Leroy, E.; Bourgon, J.; Verbeeck, J.; Andraud, C. | ||||
| Title | Nanoscale investigation by TEM and STEM-EELS of the laser induced yellowing | Type | A1 Journal article | ||
| Year | 2018 | Publication | Micron | Abbreviated Journal | Micron |
| Volume | 115 | Issue | Pages | 25-31 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Nd-YAG QS laser cleaning of soiled stone at 1064 nm can sometimes result in a more yellow appearance compared to other cleaning techniques. Especially in France, this yellowing effect is still considered as a major aesthetic issue by the architects and conservators. One explanation states that the yellowing is linked to the formation of iron-rich nanophase(s) through the laser beam interaction with black crusts that would re-deposit on the cleaned substrate after irradiation. To characterize these nanophases, a model crust containing hematite was elaborated and laser irradiated using a Nd-YAG QS laser. The color of the sample shifted instantaneously from red to a bright yellow and numerous particles were ablated in a visible smoke. Transmission electron microscopy (TEM) was used to examine the morphology and the crystallinity of the neo-formed compounds, both on the surface of the samples and in the ablated materials. In addition, an investigation of the chemical and structural properties of the nanophases was conducted by X-ray dispersive energy (EDX) and electron energy loss (EELS) spectroscopies. It was found that both the surface of the sample and the ablated materials are covered by crystallized nano-spheres and nano-residues, all containing iron and oxygen, sometimes along with calcium and sulfur. In particular an interfacial area containing the four elements was evidenced between some nanostructures and the substrate. Magnetite Fe3O4 was also identified at the nanoscale. This study demonstrates that the laser yellowing of a model crust is linked to the presence of iron-rich nanophases including CaxFeySzOδ nanostructures and magnetite Fe3O4 at the surface after irradiation. | ||||
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| Language | Wos | 000449125600004 | Publication Date | 2018-08-18 | |
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| ISSN | 0968-4328 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.98 | Times cited | 9 | Open Access |
Not_Open_Access: Available from 19.08.2020 |
| Notes | The authors wish to thank Valérie Lalanne for the sample preparation for TEM and Stijn Van den Broeck for the FIB cut elaboration. 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). | Approved | Most recent IF: 1.98 | ||
| Call Number | EMAT @ emat @c:irua:154356UA @ admin @ c:irua:154356 | Serial | 5056 | ||
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| Author | Bliokh, K.Y.; Karimi, E.; Padgett, M.J.; Alonso, M.A.; Dennis, M.R.; Dudley, A.; Forbes, A.; Zahedpour, S.; Hancock, S.W.; Milchberg, H.M.; Rotter, S.; Nori, F.; Ozdemir, S.K.; Bender, N.; Cao, H.; Corkum, P.B.; Hernandez-Garcia, C.; Ren, H.; Kivshar, Y.; Silveirinha, M.G.; Engheta, N.; Rauschenbeutel, A.; Schneeweiss, P.; Volz, J.; Leykam, D.; Smirnova, D.A.; Rong, K.; Wang, B.; Hasman, E.; Picardi, M.F.; Zayats, A.V.; Rodriguez-Fortuno, F.J.; Yang, C.; Ren, J.; Khanikaev, A.B.; Alu, A.; Brasselet, E.; Shats, M.; Verbeeck, J.; Schattschneider, P.; Sarenac, D.; Cory, D.G.; Pushin, D.A.; Birk, M.; Gorlach, A.; Kaminer, I.; Cardano, F.; Marrucci, L.; Krenn, M.; Marquardt, F. | ||||
| Title | Roadmap on structured waves | Type | A1 Journal article | ||
| Year | 2023 | Publication | Journal of optics | Abbreviated Journal | |
| Volume | 25 | Issue | 10 | Pages | 103001-103079 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Structured waves are ubiquitous for all areas of wave physics, both classical and quantum, where the wavefields are inhomogeneous and cannot be approximated by a single plane wave. Even the interference of two plane waves, or of a single inhomogeneous (evanescent) wave, provides a number of nontrivial phenomena and additional functionalities as compared to a single plane wave. Complex wavefields with inhomogeneities in the amplitude, phase, and polarization, including topological----- structures and singularities, underpin modern nanooptics and photonics, yet they are equally important, e.g. for quantum matter waves, acoustics, water waves, etc. Structured waves are crucial in optical and electron microscopy, wave propagation and scattering, imaging, communications, quantum optics, topological and non-Hermitian wave systems, quantum condensed-matter systems, optomechanics, plasmonics and metamaterials, optical and acoustic manipulation, and so forth. This Roadmap is written collectively by prominent researchers and aims to survey the role of structured waves in various areas of wave physics. Providing background, current research, and anticipating future developments, it will be of interest to a wide cross-disciplinary audience. | ||||
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| Language | Wos | 001061350200001 | Publication Date | 2023-07-26 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 2040-8978 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.1 | Times cited | 7 | Open Access |
Not_Open_Access: Available from 30.03.2024 |
| Notes | This work is funded by the Royal Society and EPSRC under the Grant Number EP/M01326X/1.M A A acknowledges funding from the Excellence Initiative of Aix Marseille University-A*MIDEX, a French Investissements d'Avenir' programme, and from the Agence Nationale de Recherche (ANR) through project ANR-21-CE24-0014-01.M R D acknowledges support from the EPSRC Centre for Doctoral Training in Topological Design(EP/S02297X/1).S R acknowledges support by the Austrian Science Fund (FWF, Grant P32300 WAVELAND) and by the European Commission (Grant MSCA-RISE 691209 NHQWAVE). FN is supported in part by NTT Research, and S K OE by the Air Force Office of Scientific Research (AFOSR) Multidisciplinary University Research Initiative (MURI) Award No. FA9550-21-1-0202.The authors thank their co-workers Yaron Bromberg, Hasan Yilmaz, and collaborators Joerg Bewersdorf and Mengyuan Sun for their contributions to the works presented here. They also acknowledge financial support from the Office of Naval Research (N00014-20-1-2197) and the National Science Foundation (DMR-1905465).H R acknowledges a support from the Australian Research Council DECRA Fellowship DE220101085. Y K acknowledges a support from the Australian Research Council (Grant DP210101292).M G S acknowledges partial support from Simons Foundation/Collaboration on Extreme Wave Phenomena Based on Symmetries, from the Institution of Engineering and Technology (IET) under the A F Harvey Research Prize 2018, and from Instituto de Telecomunicacoes under project UIDB/50008/2020. N E acknowledges partial support from Simons Foundation/Collaboration on Extreme Wave Phenomena Based on Symmetries, and from the US Air Force Office of Scientific Research (AFOSR) Multidisciplinary University Research Initiative (MURI) grant number FA9550-21-1-0312.We acknowledge funding by the Alexander von Humboldt Foundation in the framework of the Alexander von Humboldt Professorship endowed by the Federal Ministry of Education and Research. Moreover, financial support from the European Union's Horizon 2020 research and innovation program under Grant Agreement No. 899275 (DAALI) is gratefully acknowledged.D L acknowledges a support from the National Research Foundation, Singapore and A*STAR under its CQT Bridging Grant. D A S acknowledges support from the Australian Research Council (FT230100058).The authors gratefully acknowledge financial support from the Israel Science Foundation (ISF), the U.S. Air Force Office of Scientific Research (FA9550-18-1-0208) through their program on Photonic Metamaterials, the Israel Ministry of Science, Technology and Space. The fabrication was performed at the Micro-Nano Fabrication & Printing Unit(MNF & PU), Technion.This work was supported by the European Research Council projects iCOMM (789340) and Starting Grant ERC-2016-STG-714151-PSINFONI.Our work in this area has been funded by the National Science Foundation, the Office of Naval Research, and the Simons Foundation.This work was supported by the Australian Research Council Discovery Project DP190100406.J V acknowledges funding from the eBEAM Project supported by the European Union's Horizon 2020 research and innovation programme under Grant Agreement No. 101017720 (FET-Proactive EBEAM), FWO Project G042820N Exploring adaptive optics in transmission electron microscopy' and European Union's Horizon 2020 Research Infrastructure-Integrating Activities for Advanced Communities Grant Agreement No. 823717-ESTEEM3. P S acknowledges the support of the Austrian Science Fund under Project Nr. P29687-N36.; The authors would like to thank their many collaborators including Wangchun Chen, Charles W Clark, Lisa DeBeer-Schmitt, Huseyin Ekinci, Melissa Henderson, Michael Huber, Connor Kapahi, Ivar Taminiau, and Kirill Zhernenkov. The authors would also like to acknowledge their funding sources: the Canadian Excellence Research Chairs (CERC) program, the Natural Sciences and Engineering Research Council of Canada (NSERC), the Canada First Research Excellence Fund (CFREF).E K acknowledges the support of Canada Research Chairs, Ontario's Early Research Award, and NRC-uOttawa Joint Centre for Extreme Quantum Photonics (JCEP) via the High Throughput and Secure Networks Challenge Program at the National Research Council of Canada. | Approved | Most recent IF: 2.1; 2023 IF: 1.741 | ||
| Call Number | UA @ admin @ c:irua:199327 | Serial | 8925 | ||
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| Author | Goris, B.; Guzzinati, G.; Fernández-López, C.; Pérez-Juste, J.; Liz-Marzán, L.M.; Trügler, A.; Hohenester, U.; Verbeeck, J.; Bals, S.; Van Tendeloo, G. | ||||
| Title | Plasmon mapping in Au@Ag nanocube assemblies | Type | A1 Journal article | ||
| Year | 2014 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
| Volume | 118 | Issue | 28 | Pages | 15356-15362 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Surface plasmon modes in metallic nanostructures largely determine their optoelectronic properties. Such plasmon modes can be manipulated by changing the morphology of the nanoparticles or by bringing plasmonic nanoparticle building blocks close to each other within organized assemblies. We report the EELS mapping of such plasmon modes in pure Ag nanocubes, Au@Ag coreshell nanocubes, and arrays of Au@Ag nanocubes. We show that these arrays enable the creation of interesting plasmonic structures starting from elementary building blocks. Special attention will be dedicated to the plasmon modes in a triangular array formed by three nanocubes. Because of hybridization, a combination of such nanotriangles is shown to provide an antenna effect, resulting in strong electrical field enhancement at the narrow gap between the nanotriangles. | ||||
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| Publisher | Place of Publication | Washington, D.C. | Editor | ||
| Language | Wos | 000339368700031 | Publication Date | 2014-06-27 | |
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| ISSN | 1932-7447;1932-7455; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.536 | Times cited | 41 | Open Access |
OpenAccess |
| Notes | Fwo; 246791 Countatoms; 278510 Vortex; 335078 Colouratom; 262348 Esmi ECASJO;; ECASSara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); | Approved | Most recent IF: 4.536; 2014 IF: 4.772 | ||
| Call Number | UA @ lucian @ c:irua:118099UA @ admin @ c:irua:118099 | Serial | 2644 | ||
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| Author | Kurttepeli, M.; Deng, S.; Verbruggen, S.W.; Guzzinati, G.; Cott, D.J.; Lenaerts, S.; Verbeeck, J.; Van Tendeloo, G.; Detavernier, C.; Bals, S. | ||||
| Title | Synthesis and characterization of photoreactive TiO2carbon nanosheet composites | Type | A1 Journal article | ||
| Year | 2014 | Publication | The journal of physical chemistry: C : nanomaterials and interfaces | Abbreviated Journal | J Phys Chem C |
| Volume | 118 | Issue | 36 | Pages | 21031-21037 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL) | ||||
| Abstract | We report the atomic layer deposition of titanium dioxide on carbon nanosheet templates and investigate the effects of postdeposition annealing in a helium environment using different characterization techniques. The crystallization of the titanium dioxide coating upon annealing is observed using in situ X-ray diffraction. The (micro)structural characterization of the films is carried out by scanning electron microscopy and advanced transmission electron microscopy techniques. Our study shows that the annealing of the atomic layer deposition processed and carbon nanosheets templated titanium dioxide layers in helium environment resulting in the formation of a porous, nanocrystalline and photocatalytically active titanium dioxide-carbon nanosheet composite film. Such composites are suitable for photocatalysis and dye-sensitized solar cells applications. | ||||
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| Publisher | Place of Publication | Washington, D.C. | Editor | ||
| Language | Wos | 000341619500034 | Publication Date | 2014-08-23 | |
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| ISSN | 1932-7447;1932-7455; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.536 | Times cited | 9 | Open Access |
OpenAccess |
| Notes | This research was funded by the Flemish research foundation FWO-Vlaanderen, by the European Research Council (Starting Grant No. 239865) and by the Special Research Fund BOF of Ghent University (GOA-01G01513). G.G, M.K., J.V., S.B., and G.V.T. acknowledge funding from the European Research Council under the seventh Framework Program (FP7), ERC Starting Grant No. 278510 VORTEX and No. 335078 COLOURATOMS. ECASJO;; ECASSara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); | Approved | Most recent IF: 4.536; 2014 IF: 4.772 | ||
| Call Number | UA @ lucian @ c:irua:119085 | Serial | 3416 | ||
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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 | ||
| Permanent link to this record | |||||
| Author | Conings, B.; Bretschneider, S.A.; Babayigit, A.; Gauquelin, N.; Cardinaletti, I.; Manca, J.V.; Verbeeck, J.; Snaith, H.J.; Boyen, H.-G. | ||||
| Title | Structure-property relations of methylamine vapor treated hybrid perovskite CH3NH3PbI3 films and solar cells | Type | A1 Journal article | ||
| Year | 2017 | Publication | ACS applied materials and interfaces | Abbreviated Journal | Acs Appl Mater Inter |
| Volume | 9 | Issue | 9 | Pages | 8092-8099 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The power conversion efficiency of halide perovskite solar cells is heavily dependent on the perovskite layer being sufficiently smooth and pinhole-free. It has been shown that these features can be obtained even when starting out from rough and discontinuous perovskite film, by briefly exposing it to methylamine (MA) vapor. The exact underlying physical mechanisms of this phenomenon are, however, still unclear. By investigating smooth, MA treated films, based on very rough and discontinuous reference films of methylammonium triiode (MAPbI3), considering their morphology, crystalline features, local conductive properties, and charge carrier lifetime, we unravel the relation between their characteristic physical qualities and their performance in corresponding solar cells. We discover that the extensive improvement in photovoltaic performance upon MA treatment is a consequence of the induced morphological enhancement of the perovskite layer, together with improved electron injection into TiO2, which in fact compensates for an otherwise compromised bulk electronic quality, simultaneously caused by the MA treatment. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000396186000025 | Publication Date | 2017-02-10 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1944-8244 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 7.504 | Times cited | 43 | Open Access |
OpenAccess |
| Notes | This work was financially supported by BOF (Hasselt University) and the Research Fund Flanders (FWO). B.C. is a postdoctoral research fellow of the FWO. A.B. is financially supported by FWO and Imec. J.V. and N.G. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp and FWO project G.0044.13N “Charge ordering”. The Qu-Ant-EM microscope used for this study was partly funded by the Hercules fund from the Flemish Government. The authors thank Tim Vangerven for Urbach energy determination, and Johnny Baccus and Jan Mertens for technical support. | Approved | Most recent IF: 7.504 | ||
| Call Number | EMAT @ emat @ c:irua:140849 | Serial | 4422 | ||
| Permanent link to this record | |||||
| Author | Jany, B.R.; Gauquelin, N.; Willhammar, T.; Nikiel, M.; van den Bos, K.H.W.; Janas, A.; Szajna, K.; Verbeeck, J.; Van Aert, S.; Van Tendeloo, G.; Krok, F. | ||||
| Title | Controlled growth of hexagonal gold nanostructures during thermally induced self-assembling on Ge(001) surface | Type | A1 Journal article | ||
| Year | 2017 | Publication | Scientific reports | Abbreviated Journal | Sci Rep-Uk |
| Volume | 7 | Issue | 7 | Pages | 42420 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Nano-sized gold has become an important material in various fields of science and technology, where control over the size and crystallography is desired to tailor the functionality. Gold crystallizes in the face-centered cubic (fcc) phase, and its hexagonal closed packed (hcp) structure is a very unusual and rare phase. Stable Au hcp phase has been reported to form in nanoparticles at the tips of some Ge nanowires. It has also recently been synthesized in the form of thin graphene-supported sheets which are unstable under electron beam irradiation. Here, we show that stable hcp Au 3D nanostructures with well-defined crystallographic orientation and size can be systematically created in a process of thermally induced self-assembly of thin Au layer on Ge(001) monocrystal. The Au hcp crystallite is present in each Au nanostructure and has been characterized by different electron microscopy techniques. We report that a careful heat treatment above the eutectic melting temperature and a controlled cooling is required to form the hcp phase of Au on a Ge single crystal. This new method gives scientific prospects to obtain stable Au hcp phase for future applications in a rather simple manner as well as redefine the phase diagram of Gold with Germanium. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000393940700001 | Publication Date | 2017-02-14 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2045-2322 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.259 | Times cited | 25 | Open Access |
OpenAccess |
| Notes | The authors gratefully acknowledge the financial support from the Polish National Science Center, grant no. DEC-2012/07/B/ST5/00906. N.G., G.V.T. and J.V. acknowledge the European Union (EU) Council under the 7th Framework Program (FP7) ERC Starting Grant 278510 VORTEX for support. The Research Foundation Flanders is acknowledged through project fundings (G.0374.13N, G.0368.15N, G.0369.15N) and for a Ph.D. research grant to K.H.W.v.d.B. The microscope was partly funded by the Hercules Fund from the Flemish Government. T.W. acknowledges the Swedish Research Council for an international postdoc grant. 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). Part of the research was carried out with equipment purchased with financial support from the European Regional Development Fund in the framework of the Polish Innovation Economy Operational Program (Contract No. POIG.02.01.00-12-023/08). | Approved | Most recent IF: 4.259 | ||
| Call Number | EMAT @ emat @ c:irua:140846UA @ admin @ c:irua:140846 | Serial | 4423 | ||
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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. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000399084300001 | Publication Date | 2017-04-12 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.124 | Times cited | 84 | Open Access |
OpenAccess |
| Notes | ; We thank F.J. Garcia de Abajo and D.M. Ugarte for interesting and fruitful discussion. This work was supported by funding from the European Research Council under the 7th Framework Program (FP7) ERC Starting Grant 278510 VORTEX. Financial support from the European Union under the Framework 7 program under a contract for an Integrated Infrastructure Initiative (Reference number 312483 ESTEEM2) is also gratefully acknowledged. Aluminum nanostructures were fabricated using the Nanomat nanofabrication facility. ; | Approved | Most recent IF: 12.124 | ||
| Call Number | EMAT @ emat @ c:irua:142205UA @ admin @ c:irua:142205 | Serial | 4548 | ||
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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 | 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 | 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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| Corporate Author | Thesis | ||||
| 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 | Pullini, D.; Sgroi, M.; Mahmoud, A.; Gauquelin, N.; Maschio, L.; Lorenzo-Ferrari, A.M.; Groenen, R.; Damen, C.; Rijnders, G.; van den Bos, K.H.W.; Van Aert, S.; Verbeeck, J. | ||||
| Title | One step toward a new generation of C-MOS compatible oxide p-n junctions: Structure of the LSMO/ZnO interface elucidated by an experimental and theoretical synergic work | Type | A1 Journal article | ||
| Year | 2017 | Publication | ACS applied materials and interfaces | Abbreviated Journal | Acs Appl Mater Inter |
| Volume | 9 | Issue | 9 | Pages | 20974-20980 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Heterostructures formed by La0.7Sr0.3MnO3/ZnO (LSMO/ZnO) interfaces exhibit extremely interesting electronic properties making them promising candidates for novel oxide p–n junctions, with multifunctional features. In this work, the structure of the interface is studied through a combined experimental/theoretical approach. Heterostructures were grown epitaxially and homogeneously on 4″ silicon wafers, characterized by advanced electron microscopy imaging and spectroscopy and simulated by ab initio density functional theory calculations. The simulation results suggest that the most stable interface configuration is composed of the (001) face of LSMO, with the LaO planes exposed, in contact with the (112̅0) face of ZnO. The ab initio predictions agree well with experimental high-angle annular dark field scanning transmission electron microscopy images and confirm the validity of the suggested structural model. Electron energy loss spectroscopy confirms the atomic sharpness of the interface. From statistical parameter estimation theory, it has been found that the distances between the interfacial planes are displaced from the respective ones of the bulk material. This can be ascribed to the strain induced by the mismatch between the lattices of the two materials employed | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000404090000079 | Publication Date | 2017-05-25 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1944-8244 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 7.504 | Times cited | 4 | Open Access |
OpenAccess |
| Notes | Financial support is acknowledged from the European Commission – DG research and innovation to the collaborative research project named Interfacing oxides (IFOX, Contract No. NMP3-LA-2010-246102). N.G. and J.V. acknowledge the European Union (EU) Council under the 7th Framework Program (FP7) ERC Starting Grant 278510 VORTEX for support. S.V.A. and K.H.W.B. acknowledge financial support from the Research Foundation Flanders through project fundings (G.0374.13N , G.0368.15N, and G.0369.15N) and a Ph.D. research grant to K.H.W.B. The microscope was partly funded by the Hercules Fund from the Flemish Government. The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. CINECA is acknowledged for computational facilities (Iscra project HP10CMO1UP). | Approved | Most recent IF: 7.504 | ||
| Call Number | EMAT @ emat @ c:irua:144431UA @ admin @ c:irua:144431 | Serial | 4621 | ||
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| Author | Hoang, D.-Q.; Korneychuk, S.; Sankaran, K.J.; Pobedinskas, P.; Drijkoningen, S.; Turner, S.; Van Bael, M.K.; Verbeeck, J.; Nicley, S.S.; Haenen, K. | ||||
| Title | Direct nucleation of hexagonal boron nitride on diamond : crystalline properties of hBN nanowalls | Type | A1 Journal article | ||
| Year | 2017 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
| Volume | 127 | Issue | Pages | 17-24 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Hexagonal boron nitride (hBN) nanowalls were deposited by unbalanced radio frequency sputtering on (100)-oriented silicon, nanocrystalline diamond films, and amorphous silicon nitride (Si3N4) membranes. The hBN nanowall structures were found to grow vertically with respect to the surface of all of the substrates. To provide further insight into the nucleation phase and possible lattice distortion of the deposited films, the structural properties of the different interfaces were characterized by transmission electron microscopy. For Si and Si3N4 substrates, turbostratic and amorphous BN phases form a clear transition zone between the substrate and the actual hBN phase of the bulk nanowalls. However, surprisingly, the presence of these phases was suppressed at the interface with a nanocrystalline diamond film, leading to a direct coupling of hBN with the diamond surface, independent of the vertical orientation of the diamond grain. To explain these observations, a growth mechanism is proposed in which the hydrogen terminated surface of the nanocrystalline diamond film leads to a rapid formation of the hBN phase during the initial stages of growth, contrary to the case of Si and Si3N4 substrates. (C) 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. | ||||
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| Publisher | Place of Publication | Oxford | Editor | ||
| Language | Wos | Publication Date | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1359-6454 | ISBN | Additional Links | UA library record; ; WoS full record; WoS citing articles | |
| Impact Factor | 5.301 | Times cited | Open Access |
OpenAccess | |
| Notes | Approved | Most recent IF: 5.301 | |||
| Call Number | UA @ lucian @ c:irua:142398 | Serial | 4645 | ||
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| Author | Kleibert, A.; Balan, A.; Yanes, R.; Derlet, P.M.; Vaz, C.A.F.; Timm, M.; Fraile Rodríguez, A.; Béché, A.; Verbeeck, J.; Dhaka, R.S.; Radovic, M.; Nowak, U.; Nolting, F. | ||||
| Title | Direct observation of enhanced magnetism in individual size- and shape-selected 3d transition metal nanoparticles | Type | A1 Journal article | ||
| Year | 2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 95 | Issue | 95 | Pages | 195404 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Magnetic nanoparticles are critical building blocks for future technologies ranging from nanomedicine to spintronics. Many related applications require nanoparticles with tailored magnetic properties. However, despite significant efforts undertaken towards this goal, a broad and poorly understood dispersion of magnetic properties is reported, even within monodisperse samples of the canonical ferromagnetic 3d transition metals. We address this issue by investigating the magnetism of a large number of size- and shape-selected, individual nanoparticles of Fe, Co, and Ni using a unique set of complementary characterization techniques. At room temperature, only superparamagnetic behavior is observed in our experiments for all Ni nanoparticles within the investigated sizes, which range from 8 to 20 nm. However, Fe and Co nanoparticles can exist in two distinct magnetic states at any size in this range: (i) a superparamagnetic state, as expected from the bulk and surface anisotropies known for the respective materials and as observed for Ni, and (ii) a state with unexpected stable magnetization at room temperature. This striking state is assigned to significant modifications of the magnetic properties arising from metastable lattice defects in the core of the nanoparticles, as concluded by calculations and atomic structural characterization. Also related with the structural defects, we find that the magnetic state of Fe and Co nanoparticles can be tuned by thermal treatment enabling one to tailor their magnetic properties for applications. This paper demonstrates the importance of complementary single particle investigations for a better understanding of nanoparticle magnetism and for full exploration of their potential for applications. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000400665300002 | Publication Date | 2017-05-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 21 | Open Access |
OpenAccess |
| Notes | We thank A. Weber, R. Schelldorfer, and J. Krbanjevic (Paul Scherrer Institut) for technical assistance. This paper was supported by the Swiss Nanoscience Institute, University of Basel. A.F.R. acknowledges support from the MICIIN “Ramón y Cajal” Programme. A.B. and J.V. acknowledge funding from the European Union under the European Research Council (ERC) Starting Grant No. 278510 VORTEX and under a contract for Integrated Infrastructure Initiative ESTEEM2 No. 312483. R.Y. and U.N. thank the Deutsche Forschungsgemeinschaft for financial support via Sonderforschungsbereich 1214. Part of this work was performed at the Surface/Interface: Microscopy (SIM) beamline of the Swiss Light Source, Paul Scherrer Institut, Villigen, Switzerland. | Approved | Most recent IF: 3.836 | ||
| Call Number | EMAT @ emat @ c:irua:143634UA @ admin @ c:irua:143634 | Serial | 4575 | ||
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| Author | 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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| 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 | ; 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 | ||
| Permanent link to this record | |||||
| Author | Korneychuk, S.; Partoens, B.; Guzzinati, G.; Ramaneti, R.; Derluyn, J.; Haenen, K.; Verbeeck, J. | ||||
| Title | Exploring possibilities of band gap measurement with off-axis EELS in TEM | Type | A1 Journal article | ||
| Year | 2018 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 189 | Issue | 189 | Pages | 76-84 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract | A technique to measure the band gap of dielectric materials with high refractive index by means of energy electron loss spectroscopy (EELS) is presented. The technique relies on the use of a circular (Bessel) aperture and suppresses Cherenkov losses and surface-guided light modes by enforcing a momentum transfer selection. The technique also strongly suppresses the elastic zero loss peak, making the acquisition, interpretation and signal to noise ratio of low loss spectra considerably better, especially for excitations in the first few eV of the EELS spectrum. Simulations of the low loss inelastic electron scattering probabilities demonstrate the beneficial influence of the Bessel aperture in this setup even for high accelerating voltages. The importance of selecting the optimal experimental convergence and collection angles is highlighted. The effect of the created off-axis acquisition conditions on the selection of the transitions from valence to conduction bands is discussed in detail on a simplified isotropic two band model. This opens the opportunity for deliberately selecting certain transitions by carefully tuning the microscope parameters. The suggested approach is experimentally demonstrated and provides good signal to noise ratio and interpretable band gap signals on reference samples of diamond, GaN and AlN while offering spatial resolution in the nm range. (C) 2018 Elsevier B.V. All rights reserved. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000432868500008 | Publication Date | 2018-03-29 | |
| 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 |
OpenAccess |
| Notes | ; S.K., B.P. and J.V. acknowledge funding from the “Geconcentreerde Onderzoekacties” (GOA) project “Solarpaint” of the University of Antwerp. S.K. and J.V. also acknowledge the FWO-Vlaanderen for financial support under contract G.0044.13N 'Charge ordering'. Financial support via the Methusalem “NANO” network is acknowledged. GG acknowledges support from a postdoctoral fellowship grant from the Fonds Wetenschappelijk Onderzoek-Vlaanderen (FWO). ; | Approved | Most recent IF: 2.843 | ||
| Call Number | UA @ lucian @ c:irua:151472UA @ admin @ c:irua:151472 | Serial | 5026 | ||
| Permanent link to this record | |||||
| Author | Guzzinati, G.; Altantzis, T.; Batuk, M.; De Backer, A.; Lumbeeck, G.; Samaee, V.; Batuk, D.; Idrissi, H.; Hadermann, J.; Van Aert, S.; Schryvers, D.; Verbeeck, J.; Bals, S. | ||||
| Title | Recent Advances in Transmission Electron Microscopy for Materials Science at the EMAT Lab of the University of Antwerp | Type | A1 Journal article | ||
| Year | 2018 | Publication | Materials | Abbreviated Journal | Materials |
| Volume | 11 | Issue | 11 | Pages | 1304 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | The rapid progress in materials science that enables the design of materials down to the nanoscale also demands characterization techniques able to analyze the materials down to the same scale, such as transmission electron microscopy. As Belgium’s foremost electron microscopy group, among the largest in the world, EMAT is continuously contributing to the development of TEM techniques, such as high-resolution imaging, diffraction, electron tomography, and spectroscopies, with an emphasis on quantification and reproducibility, as well as employing TEM methodology at the highest level to solve real-world materials science problems. The lab’s recent contributions are presented here together with specific case studies in order to highlight the usefulness of TEM to the advancement of materials science. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000444112800041 | Publication Date | 2018-07-28 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1996-1944 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.654 | Times cited | 15 | Open Access |
OpenAccess |
| Notes | Fonds Wetenschappelijk Onderzoek, G.0502.18N, G.0267.18N, G.0120.12N, G.0365.15N, G.0934.17N, S.0100.18N AUHA13009 ; European Research Council, COLOURATOM 335078 ; Universiteit Antwerpen, GOA Solarpaint ; G. Guzzinati, T. Altantzis and A. De Backer have been supported by postdoctoral fellowship grants from the Research Foundation Flanders (FWO). Funding was also received from the European Research Council (starting grant no. COLOURATOM 335078), the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 770887), the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0502.18N, G.0267.18N, G.0120.12N, G.0365.15N, G.0934.17N, S.0100.18N, G.0401.16N) and from the University of Antwerp through GOA project Solarpaint. Funding for the TopSPIN precession system under grant AUHA13009, as well as for the Qu-Ant-EM microscope, is acknowledged from the HERCULES Foundation. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (F.R.S.-FNRS). (ROMEO:green; preprint:; postprint:can ; pdfversion:can); saraecas; ECAS_Sara; | Approved | Most recent IF: 2.654 | ||
| Call Number | EMAT @ emat @c:irua:153737UA @ admin @ c:irua:153737 | Serial | 5064 | ||
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| Author | Liao, Z.; Gauquelin, N.; Green, R.J.; Müller-Caspary, K.; Lobato, I.; Li, L.; Van Aert, S.; Verbeeck, J.; Huijben, M.; Grisolia, M.N.; Rouco, V.; El Hage, R.; Villegas, J.E.; Mercy, A.; Bibes, M.; Ghosez, P.; Sawatzky, G.A.; Rijnders, G.; Koster, G. | ||||
| Title | Metal–insulator-transition engineering by modulation tilt-control in perovskite nickelates for room temperature optical switching | Type | A1 Journal article | ||
| Year | 2018 | Publication | America | Abbreviated Journal | P Natl Acad Sci Usa |
| Volume | 115 | Issue | 38 | Pages | 9515-9520 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In transition metal perovskites ABO3 the physical properties are largely driven by the rotations of the BO6 octahedra, which can be tuned in thin films through strain and dimensionality control. However, both approaches have fundamental and practical limitations due to discrete and indirect variations in bond angles, bond lengths and film symmetry by using commercially available substrates. Here, we introduce modulation tilt control as a new approach to tune the ground state of perovskite oxide thin films by acting explicitly on the oxygen octahedra rotation modes, i.e. directly on the bond angles. By intercalating the prototype SmNiO3 target material with a tilt-control layer, we cause the system to change the natural amplitude of a given rotation mode without affecting the interactions. In contrast to strain and dimensionality engineering, our method enables a continuous fine-tuning of the materials properties. This is achieved through two independent adjustable parameters: the nature of the tilt-control material (through its symmetry, elastic constants and oxygen rotation angles) and the relative thicknesses of the target and tilt-control materials. As a result, a magnetic and electronic phase diagram can be obtained, normally only accessible by A-site element substitution, within the single SmNiO3 compound. With this unique approach, we successfully adjusted the metal-insulator transition (MIT) to room temperature to fulfill the desired conditions for optical switching applications. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000447224900057 | Publication Date | 2018-09-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0027-8424 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 9.661 | Times cited | 50 | Open Access |
OpenAccess |
| Notes | We would like to acknowledge Prof. Z. Zhong for stimulated discussion. M.H., G.K. and G.R. acknowledge funding from DESCO program of the Dutch Foundation for Fundamental Research on Matter (FOM) with financial support from the Netherlands Organization for Scientific Research (NWO). This work was funded by the European Union Council under the 7th Framework Program (FP7) grant nr NMP3-LA-2010-246102 IFOX. J.V., S.V.A, N.G. and K.M.C. acknowledge funding from FWO projects G.0044.13N, G.0374.13N, G. 0368.15N, and G.0369.15N. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. N.G. and J.V. 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 Canadian work was supported by NSERC and the Max Planck-UBC Centre for Quantum Materials. Some experiments for this work were performed at the Canadian Light Source, which is funded by the Canada Foundation for Innovation, NSERC, the National Research Council of Canada, the Canadian Institutes of Health Research, the Government of Saskatchewan, Western Economic Diversification Canada, and the University of Saskatchewan. MB acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC CoG grant MINT #615759. A.M. and Ph.G. were supported by the ARC project AIMED and F.R.S-FNRS PDR project HiT4FiT and acknowledge access to Céci computing facilities funded by F.R.S-FNRS (Grant No 2.5020.1), Tier-1 supercomputer of the Fédération Wallonie-Bruxelles funded by the Walloon Region (Grant No 1117545) and HPC resources from the PRACE project Megapasta. | Approved | Most recent IF: 9.661 | ||
| Call Number | EMAT @ emat @c:irua:154784UA @ admin @ c:irua:154784 | Serial | 5059 | ||
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| Author | Krehl, J.; Guzzinati, G.; Schultz, J.; Potapov, P.; Pohl, D.; Martin, J.; Verbeeck, J.; Fery, A.; Büchner, B.; Lubk, A. | ||||
| Title | Spectral field mapping in plasmonic nanostructures with nanometer resolution | Type | A1 Journal article | ||
| Year | 2018 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
| Volume | 9 | Issue | 1 | Pages | 4207 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Plasmonic nanostructures and -devices are rapidly transforming light manipulation technology by allowing to modify and enhance optical fields on sub-wavelength scales. Advances in this field rely heavily on the development of new characterization methods for the fundamental nanoscale interactions. However, the direct and quantitative mapping of transient electric and magnetic fields characterizing the plasmonic coupling has been proven elusive to date. Here we demonstrate how to directly measure the inelastic momentum transfer of surface plasmon modes via the energy-loss filtered deflection of a focused electron beam in a transmission electron microscope. By scanning the beam over the sample we obtain a spatially and spectrally resolved deflection map and we further show how this deflection is related quantitatively to the spectral component of the induced electric and magnetic fields pertaining to the mode. In some regards this technique is an extension to the established differential phase contrast into the dynamic regime. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000447074200005 | Publication Date | 2018-10-11 | |
| 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 | 15 | Open Access |
OpenAccess |
| Notes | G.G. acknowledges support from a postdoctoral fellowship grant from the Fonds Wetenschappelijk Onderzoke-Vlaanderen (FWO). A.L. and J.K. have received funding from the European Research Council (ERC) under the Horizon 2020 research and innovation program of the European Union (grant agreement no. 715620). | Approved | Most recent IF: 12.124 | ||
| Call Number | EMAT @ emat @c:irua:154355 | Serial | 5058 | ||
| Permanent link to this record | |||||
| Author | Müller-Caspary, K.; Grieb, T.; Müßener, J.; Gauquelin, N.; Hille, P.; Schörmann, J.; Verbeeck, J.; Van Aert, S.; Eickhoff, M.; Rosenauer, A. | ||||
| Title | Electrical Polarization in AlN/GaN Nanodisks Measured by Momentum-Resolved 4D Scanning Transmission Electron Microscopy | Type | A1 Journal article | ||
| Year | 2019 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
| Volume | 122 | Issue | 10 | Pages | 106102 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | We report the mapping of polarization-induced internal electric fields in AlN/GaN nanowire heterostructures at unit cell resolution as a key for the correlation of optical and structural phenomena in semiconductor optoelectronics. Momentum-resolved aberration-corrected scanning transmission electron microscopy is employed as a new imaging mode that simultaneously provides four-dimensional data in real and reciprocal space. We demonstrate how internal mesoscale and atomic electric fields can be separated in an experiment, which is verified by comprehensive dynamical simulations of multiple electron scattering. A mean difference of 5.3 +- 1.5 MV/cm is found for the polarization-induced electric fields in AlN and GaN, being in accordance with dedicated simulations and photoluminescence measurements in previous publications. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000461067700007 | Publication Date | 2019-03-11 | |
| 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 | 26 | Open Access |
OpenAccess |
| Notes | The authors gratefully acknowledge the help of Natalie Claes for analyzing the EDX data. K. M.-C. acknowledges funding from the Initiative and Network Fund of the Helmholtz Association within the Helmholtz Young Investigator Group moreSTEM under Contract No. VHNG- 1317 at Forschungszentrum Jülich in Germany. The direct electron detector (Medipix3, Quantum Detectors) was funded by the Hercules fund from the Flemish Government. N. G. and J. V. acknowledge funding from the Geconcentreerde Onderzoekacties project Solarpaint of the University of Antwerp. T. G. and A. R. acknowledge support from the Deutsche Forschungsgemeinschaft (Germany) under Contract No. RO2057/8-3. This work also received funding from the European Research Council under the European Union’s Horizon 2020 research and innovation programme (Contract No. 770887). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project funding (G.0368.15N).; Helmholtz Association, VH-NG-1317 ; Forschungszentrum Jülich; Flemish Government; Universiteit Antwerpen; Deutsche Forschungsgemeinschaft, RO2057/8-3 ; H2020 European Research Council, 770887 ; Fonds Wetenschappelijk Onderzoek, G.0368.15N ; | Approved | Most recent IF: 8.462 | ||
| Call Number | UA @ lucian @UA @ admin @ c:irua:158120 | Serial | 5157 | ||
| Permanent link to this record | |||||
| Author | Jannis, D.; Müller-Caspary, K.; Béché, A.; Oelsner, A.; Verbeeck, J. | ||||
| Title | Spectroscopic coincidence experiments in transmission electron microscopy | Type | A1 Journal article | ||
| Year | 2019 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
| Volume | 114 | Issue | 14 | Pages | 143101 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | We demonstrate the feasibility of coincidence measurements on a conventional transmission electron microscope, revealing the temporal correlation between electron energy loss spectroscopy (EELS) and energy dispersive X-ray (EDX) spectroscopy events. We make use of a delay line detector with ps-range time resolution attached to a modified EELS spectrometer. We demonstrate that coincidence between both events, related to the excitation and deexcitation of atoms in a crystal, provides added information not present in the individual EELS or EDX spectra. In particular, the method provides EELS with a significantly suppressed or even removed background, overcoming the many difficulties with conventional parametric background fitting as it uses no assumptions on the shape of the background, requires no user input and does not suffer from counting noise originating from the background signal. This is highly attractive, especially when low concentrations of elements need to be detected in a matrix of other elements. |
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000464450200022 | Publication Date | 2019-04-08 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-6951 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.411 | Times cited | 18 | Open Access |
OpenAccess |
| Notes | Fonds Wetenschappelijk Onderzoek, G093417 ; Horizon 2020 Framework Programme, 823717 ESTEEM3 ; Helmholtz Association, VH-NG-1327 ; | Approved | Most recent IF: 3.411 | ||
| Call Number | EMAT @ emat @UA @ admin @ c:irua:159155 | Serial | 5168 | ||
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| Author | Guzzinati, G.; Ghielens, W.; Mahr, C.; Béché, A.; Rosenauer, A.; Calders, T.; Verbeeck, J. | ||||
| Title | Electron Bessel beam diffraction for precise and accurate nanoscale strain mapping | Type | A1 Journal article | ||
| Year | 2019 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
| Volume | 114 | Issue | 24 | Pages | 243501 |
| Keywords | A1 Journal article; ADReM Data Lab (ADReM); Electron microscopy for materials research (EMAT) | ||||
| Abstract | Strain has a strong effect on the properties of materials and the performance of electronic devices. Their ever shrinking size translates into a constant demand for accurate and precise measurement methods with a very high spatial resolution. In this regard, transmission electron microscopes are key instruments thanks to their ability to map strain with a subnanometer resolution. Here, we present a method to measure strain at the nanometer scale based on the diffraction of electron Bessel beams. We demonstrate that our method offers a strain sensitivity better than 2.5 × 10−4 and an accuracy of 1.5 × 10−3, competing with, or outperforming, the best existing methods with a simple and easy to use experimental setup. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000472599100019 | Publication Date | 2019-06-17 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0003-6951 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.411 | Times cited | 17 | Open Access |
OpenAccess |
| Notes | Deutsche Forschungsgemeinschaft, RO2057/12-2 ; Fonds Wetenschappelijk Onderzoek, G.0934.17N ; | Approved | Most recent IF: 3.411 | ||
| Call Number | EMAT @ emat @UA @ admin @ c:irua:160119 | Serial | 5181 | ||
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| Author | Becker, M.; Guzzinati, G.; Béché, A.; Verbeeck, J.; Batelaan, H. | ||||
| Title | Asymmetry and non-dispersivity in the Aharonov-Bohm effect | Type | A1 Journal article | ||
| Year | 2019 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
| Volume | 10 | Issue | 10 | Pages | 1700 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Decades ago, Aharonov and Bohm showed that electrons are affected by electromagnetic potentials in the absence of forces due to fields. Zeilinger's theorem describes this absence of classical force in quantum terms as the “dispersionless” nature of the Aharonov-Bohm effect. Shelankov predicted the presence of a quantum “force” for the same Aharonov-Bohm physical system as elucidated by Berry. Here, we report an experiment designed to test Shelankov's prediction and we provide a theoretical analysis that is intended to elucidate the relation between Shelankov's prediction and Zeilinger's theorem. The experiment consists of the Aharonov-Bohm physical system; free electrons pass a magnetized nanorod and far-field electron diffraction is observed. The diffraction pattern is asymmetric confirming one of Shelankov's predictions and giving indirect experimental evidence for the presence of a quantum “force”. Our theoretical analysis shows that Zeilinger's theorem and Shelankov's result are both special cases of one theorem. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000464338100011 | Publication Date | 2019-04-12 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.124 | Times cited | 12 | Open Access |
OpenAccess |
| Notes | ; H.B. would like to thank Michael Berry for bringing the presence of a quantum “force” to our attention. A.B., G.G. and J.V. acknowledge support from the European Research Council under the 7th Framework Program (FP7) ERC Starting Grant 278510 VORTEX. G.G. acknowledges support from the Fonds Wetenschappelijk Onderzoek -Vlaanderen (FWO). M.B. and H.B. acknowledge support by the U.S. National Science Foundation under Grant No. 1602755. ; | Approved | Most recent IF: 12.124 | ||
| Call Number | UA @ admin @ c:irua:159341 | Serial | 5241 | ||
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| Author | Müller-Caspary, K.; Krause, F.F.; Winkler, F.; Béché, A.; Verbeeck, J.; Van Aert, S.; Rosenauer, A. | ||||
| Title | Comparison of first moment STEM with conventional differential phase contrast and the dependence on electron dose | Type | A1 Journal article | ||
| Year | 2019 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 203 | Issue | 203 | Pages | 95-104 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | This study addresses the comparison of scanning transmission electron microscopy (STEM) measurements of momentum transfers using the first moment approach and the established method that uses segmented annular detectors. Using an ultrafast pixelated detector to acquire four-dimensional, momentum-resolved STEM signals, both the first moment calculation and the calculation of the differential phase contrast (DPC) signals are done for the same experimental data. In particular, we investigate the ability to correct the segment-based signal to yield a suitable approximation of the first moment for cases beyond the weak phase object approximation. It is found that the measurement of momentum transfers using segmented detectors can approach the first moment measurement as close as 0.13 h/nm in terms of a root mean square (rms) difference in 10 nm thick SrTiO3 for a detector with 16 segments. This amounts to 35% of the rms of the momentum transfers. In addition, we present a statistical analysis of the precision of first moment STEM as a function of dose. For typical experimental settings with recent hardware such as a Medipix3 Merlin camera attached to a probe-corrected STEM, we find that the precision of the measurement of momentum transfers stagnates above certain doses. This means that other instabilities such as specimen drift or scan noise have to be taken into account seriously for measurements that target, e.g., the detection of bonding effects in the charge density. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000465021000013 | Publication Date | 2018-12-30 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 25 | Open Access |
OpenAccess |
| Notes | ; The direct electron detector (Medipix3 Merlin) was funded by the Hercules fund from the Flemish Government. K. Muller-Caspary acknowledges funding from the Initiative and Network Fund of the Helmholtz Association within the framework of the Helmholtz Young Investigator Group moreSTEM (VH-NG-1317) at Forschungszentrum Julich, Germany. F. F. Krause acknowledges funding from the Central Research Development Fund of the University of Bremen, Germany. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant Agreement No. 770887). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) and the Research Fund of the University of Antwerp. ; | Approved | Most recent IF: 2.843 | ||
| Call Number | UA @ admin @ c:irua:160213 | Serial | 5242 | ||
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| Author | 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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| 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 | ; 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 | ||
| Permanent link to this record | |||||