| Records |
| Author |
Schattschneider, P.; Schachinger, T.; Verbeeck, J. |
| Title |
Ein Whirlpool aus Elektronen: Transmissions-Elektronenmikroskopie mit Elektronenwirbeln |
Type |
A1 Journal article |
Year  |
2018 |
Publication |
Physik in unserer Zeit |
Abbreviated Journal |
Phys. Unserer Zeit |
| Volume |
49 |
Issue |
1 |
Pages |
22-28 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Elektronen bewegen sich im feldfreien Raum immer gleichförmig geradlinig, so steht es in den Lehrbüchern. Falsch, sagen wir. Elektronen lassen sich zu Tornados formen, die theoretisch Nanopartikel zerreißen können. In der Elektronenmikroskopie eingesetzt, versprechen sie neue Erkenntnisse in der Festkörperphysik. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
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Publication Date |
2018-01-02 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0031-9252 |
ISBN |
|
Additional Links |
UA library record |
| Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
| Notes |
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Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @c:irua:148159 |
Serial |
4806 |
| Permanent link to this record |
| |
|
| |
| Author |
Li, L.; Liao, Z.; Gauquelin, N.; Minh Duc Nguyen; Hueting, R.J.E.; Gravesteijn, D.J.; Lobato, I.; Houwman, E.P.; Lazar, S.; Verbeeck, J.; Koster, G.; Rijnders, G. |
| Title |
Epitaxial stress-free growth of high crystallinity ferroelectric PbZr0.52Ti0.48O3 on GaN/AlGaN/Si(111) substrate |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Advanced Materials Interfaces |
Abbreviated Journal |
Adv Mater Interfaces |
| Volume |
5 |
Issue |
2 |
Pages |
1700921 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
<script type='text/javascript'>document.write(unpmarked('Due to its physical properties gallium-nitride (GaN) is gaining a lot of attention as an emerging semiconductor material in the field of high-power and high-frequency electronics applications. Therefore, the improvement in the performance and/or perhaps even extension in functionality of GaN based devices would be highly desirable. The integration of ferroelectric materials such as lead-zirconate-titanate (PbZrxTi1-xO3) with GaN has a strong potential to offer such an improvement. However, the large lattice mismatch between PZT and GaN makes the epitaxial growth of Pb(Zr1-xTix)O-3 on GaN a formidable challenge. This work discusses a novel strain relaxation mechanism observed when MgO is used as a buffer layer, with thicknesses down to a single unit cell, inducing epitaxial growth of high crystallinity Pb(Zr0.52Ti0.48)O-3 (PZT) thin films. The epitaxial PZT films exhibit good ferroelectric properties, showing great promise for future GaN device applications.')); |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000423173800005 |
Publication Date |
2017-11-27 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2196-7350 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.279 |
Times cited |
15 |
Open Access |
Not_Open_Access |
| Notes |
; L.L., Z.L.L., and N.G. contributed equally to this work. L.L. acknowledges financial support from Nano Next NL (Grant no. 7B 04). The authors acknowledge NXP for providing the GaN/AlGaN/Si (111) wafer. N.G. acknowledges funding from the Geconcentreerde Onderzoekacties (GOA) project “Solarpaint” of the University of Antwerp and J.V. acknowledges funding from the Research Foundation Flanders (FWO, Belgium) project 42/FA070100/6088 “nieuwe eigenschappen in complexe Oxides.” N.G. acknowledges the EUROTAPES project (FP7-NMP.2011.2.2-1 Grant no. 280432) which partly funded this study. ; |
Approved |
Most recent IF: 4.279 |
| Call Number |
UA @ lucian @ c:irua:148427UA @ admin @ c:irua:148427 |
Serial |
4872 |
| Permanent link to this record |
| |
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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.')); |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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| Language |
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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 |
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| |
| Author |
Zhou, Y.; Ramaneti, R.; Anaya, J.; Korneychuk, S.; Derluyn, J.; Sun, H.; Pomeroy, J.; Verbeeck, J.; Haenen, K.; Kuball, M. |
| Title |
Thermal characterization of polycrystalline diamond thin film heat spreaders grown on GaN HEMTs |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
111 |
Issue |
4 |
Pages |
041901 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Polycrystalline diamond (PCD) was grown onto high-k dielectric passivated AlGaN/GaN-on-Si high electron mobility transistor (HEMT) structures, with film thicknesses ranging from 155 to 1000 nm. Transient thermoreflectance results were combined with device thermal simulations to investigate the heat spreading benefit of the diamond layer. The observed thermal conductivity (k(Dia)) of PCD films is one-to-two orders of magnitude lower than that of bulk PCD and exhibits a strong layer thickness dependence, which is attributed to the grain size evolution. The films exhibit a weak temperature dependence of k(Dia) in the measured 25-225 degrees C range. Device simulation using the experimental jDia and thermal boundary resistance values predicts at best a 15% reduction in peak temperature when the source-drain opening of a passivated AlGaN/GaN-on-Si HEMT is overgrown with PCD. Published by AIP Publishing. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
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Wos |
000406779700008 |
Publication Date |
2017-07-24 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.411 |
Times cited |
78 |
Open Access |
Not_Open_Access |
| Notes |
; The authors are grateful to Professor Michael Uren and Dr. Roland B. Simon (University of Bristol) for helpful discussions and to Dr. Sien Drijkoningen (Hasselt University) for taking the SEM micrographs. This work was in part supported by DARPA under Contract No. FA8650-15-C-7517, monitored by Dr. Avram Bar Cohen and Dr. John Blevins, and supported by Dr. Joseph Maurer and Dr. Abirami Sivananthan. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of DARPA. Y.Z. acknowledges China Scholarship Council for the financial support. S.K. and J.V. acknowledge the FWO-Vlaanderen for financial support under contract G.0044.13N “Charge ordering.” ; |
Approved |
Most recent IF: 3.411 |
| Call Number |
UA @ lucian @ c:irua:145203 |
Serial |
4728 |
| Permanent link to this record |
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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. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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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 |
; 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 |
| Permanent link to this record |
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| |
| Author |
Vatanparast, M.; Egoavil, R.; Reenaas, T.W.; Verbeeck, J.; Holmestad, R.; Vullum, P.E. |
| Title |
Bandgap measurement of high refractive index materials by off-axis EELS |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
| Volume |
182 |
Issue |
|
Pages |
92-98 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
In the present work Cs aberration corrected and monochromated scanning transmission electron microscopy electron energy loss spectroscopy (STEM-EELS) has been used to explore experimental setups that allow bandgaps of high refractive index materials to be determined. Semi-convergence and collection angles in the mu rad range were combined with off-axis or dark field EELS to avoid relativistic losses and guided light modes in the low loss range to contribute to the acquired EEL spectra. Off-axis EELS further supressed the zero loss peak and the tail of the zero loss peak. The bandgap of several GaAs-based materials were successfully determined by simple regression analyses of the background subtracted EEL spectra. The presented set-up does not require that the acceleration voltage is set to below the. Cerenkov limit and can be applied over the entire acceleration voltage range of modern TEMs and for a wide range of specimen thicknesses. (C) 2017 Elsevier B.V. All rights reserved. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Amsterdam |
Editor |
|
| Language |
|
Wos |
000413436500013 |
Publication Date |
2017-06-21 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.843 |
Times cited |
3 |
Open Access |
Not_Open_Access |
| Notes |
; The authors would like to thank Professor Shu Min Wang and Mahdad Sadeghi at the Nanofabrication Laboratory at Chalmers University, Sweden for providing the samples. The Norwegian Research Council is acknowledged for funding the HighQ-IB project under contract no. 10415201. M.V. and T.W.R. acknowledge funding from the EEA Financial Mechanism 2009-2014 under the project contract no 23SEE/30.06.2014. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2(Integrated Infrastructure Initiative-I3) through the system of transnational access. R.E. and J.V. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp. ; |
Approved |
Most recent IF: 2.843 |
| Call Number |
UA @ lucian @ c:irua:146639UA @ admin @ c:irua:146639 |
Serial |
4778 |
| Permanent link to this record |
| |
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| |
| Author |
Ramaneti, R.; Sankaran, K.J.; Korneychuk, S.; Yeh, C.J.; Degutis, G.; Leou, K.C.; Verbeeck, J.; Van Bael, M.K.; Lin, I.N.; Haenen, K. |
| Title |
Vertically aligned diamond-graphite hybrid nanorod arrays with superior field electron emission properties |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
APL materials |
Abbreviated Journal |
Apl Mater |
| Volume |
5 |
Issue |
6 |
Pages |
066102 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| Abstract |
A “patterned-seeding technique” in combination with a “nanodiamond masked reactive ion etching process” is demonstrated for fabricating vertically aligned diamond-graphite hybrid (DGH) nanorod arrays. The DGH nanorod arrays possess superior field electron emission (FEE) behavior with a low turn-on field, long lifetime stability, and large field enhancement factor. Such an enhanced FEE is attributed to the nanocomposite nature of theDGHnanorods, which contain sp(2)-graphitic phases in the boundaries of nano-sized diamond grains. The simplicity in the nanorod fabrication process renders the DGH nanorods of greater potential for the applications as cathodes in field emission displays and microplasma display devices. (C) 2017 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000404623000002 |
Publication Date |
2017-06-08 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2166-532x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.335 |
Times cited |
16 |
Open Access |
|
| Notes |
The authors would like to thank the Methusalem “NANO” network for financial support and Mr. B. Ruttens and Professor Jan D'Haen for technical and experimental assistance. K.J. Sankaran is a Postdoctoral Fellow of the Research Foundation-Flanders (FWO). |
Approved |
Most recent IF: 4.335 |
| Call Number |
UA @ admin @ c:irua:152633 |
Serial |
5369 |
| Permanent link to this record |
| |
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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. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000411170800022 |
Publication Date |
2017-06-03 |
| Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.843 |
Times cited |
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 |
| Permanent link to this record |
| |
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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 |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000406169900001 |
Publication Date |
2017-05-29 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| 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 |
| Permanent link to this record |
| |
|
| |
| 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 |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000404090000079 |
Publication Date |
2017-05-25 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| 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 |
| Permanent link to this record |
| |
|
| |
| Author |
Kleibert, A.; Balan, A.; Yanes, R.; Derlet, P.M.; Vaz, C.A.F.; Timm, M.; Fraile Rodríguez, A.; Béché, A.; Verbeeck, J.; Dhaka, R.S.; Radovic, M.; Nowak, U.; Nolting, F. |
| Title |
Direct observation of enhanced magnetism in individual size- and shape-selected 3d transition metal nanoparticles |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
95 |
Issue |
95 |
Pages |
195404 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Magnetic nanoparticles are critical building blocks for future technologies ranging from nanomedicine to spintronics. Many related applications require nanoparticles with tailored magnetic properties. However, despite significant efforts undertaken towards this goal, a broad and poorly understood dispersion of magnetic properties is reported, even within monodisperse samples of the canonical ferromagnetic 3d transition metals. We address this issue by investigating the magnetism of a large number of size- and shape-selected, individual nanoparticles of Fe, Co, and Ni using a unique set of complementary characterization techniques. At room temperature, only superparamagnetic behavior is observed in our experiments for all Ni nanoparticles within the investigated sizes, which range from 8 to 20 nm. However, Fe and Co nanoparticles can exist in two distinct magnetic states at any size in this range: (i) a superparamagnetic state, as expected from the bulk and surface anisotropies known for the respective materials and as observed for Ni, and (ii) a state with unexpected stable magnetization at room temperature. This striking state is assigned to significant modifications of the magnetic properties arising from metastable lattice defects in the core of the nanoparticles, as concluded by calculations and atomic structural characterization. Also related with the structural defects, we find that the magnetic state of Fe and Co nanoparticles can be tuned by thermal treatment enabling one to tailor their magnetic properties for applications. This paper demonstrates the importance of complementary single particle investigations for a better understanding of nanoparticle magnetism and for full exploration of their potential for applications. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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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 |
| Permanent link to this record |
| |
|
| |
| Author |
Smolin, S.Y.; Choquette, A.K.; Wilks, R.G.; Gauquelin, N.; Félix, R.; Gerlach, D.; Ueda, S.; Krick, A.L.; Verbeeck, J.; Bär, M.; Baxter, J.B.; May, S.J. |
| Title |
Energy Level Alignment and Cation Charge States at the LaFeO3/LaMnO3(001) Heterointerface |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Advanced Materials Interfaces |
Abbreviated Journal |
Adv Mater Interfaces |
| Volume |
4 |
Issue |
4 |
Pages |
1700183 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The electronic properties of LaFeO 3 /LaMnO 3 epitaxial heterojunctions are investigated to determine the valence and conduction band offsets and the nominal Mn and Fe valence states at the interface. Studying a systematic series of (LaFeO 3 ) n /(LaMnO 3 ) m bilayers (m ≈ 50) epitaxially grown in the (001) orientation using molecular beam epitaxy, layer-resolved electron energy loss spectroscopy reveals a lack of significant interfacial charge transfer, with a nominal 3+ valence state observed for both Mn and Fe across the interface. Through a combination of variable angle spectroscopic ellipsometry and hard X-ray photoelectron spectroscopy, type I energy level alignments are obtained at the LaFeO 3 /LaMnO 3 interface with positive valence and conduction band offsets of (1.20 ± 0.07) eV and (0.5–0.7 ± 0.3) eV, respectively, with minimal band bending. Variable temperature resistivity measurements reveal that the bilayers remain insulating and that the presence of the heterojunction does not result in a conducting interface. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Wos |
000406068400011 |
Publication Date |
2017-04-26 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2196-7350 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.279 |
Times cited |
14 |
Open Access |
Not_Open_Access |
| Notes |
The authors thank Dmytro Nykypanchuk for assistance with the near- infrared ellipsometry measurement of the LaMnO 3 film. S.Y.S., A.K.C., J.B.B, and S.J.M. acknowledge funding from the National Science Foundation under grant number ECCS-1201957. S.Y.S. acknowledges additional funding from the German Academic Exchange Service (DAAD) through the Research Internships in Science and Engineering (RISE) professional program 2015 ID 5708457. A.L.K. was funded by the National Science Foundation under grant number DMR-1151649. J.V. and N.G. acknowledge funding through the GOA project “Solarpaint” of the University of Antwerp and from the FWO project G.0044.13N (Charge ordering). The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. Ellipsometry measurements of the LaMnO 3 film were carried out at the Center for Functional Nanomaterials, Brookhaven National Laboratory, which is supported by the U.S. Department of Energy, Office of Basic Energy Sciences, under Contract No. DE-ACO2-98CH10886. S.U. would like to thank the staff of HiSOR, Hiroshima University, and JAEA/Spring-8 for the development of HAXPES at BL15XU of SPring-8. The HAXPES measurements were performed with approval of NIMS Synchrotron X-ray Station (Proposal No. 2015B4601), and were partly supported by the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan. The authors also thank HZB for the allocation of synchrotron radiation beamtime for HAXPES/XANES measurements. R.G.W., R.F, and M.B. are grateful to the Impuls- und Vernetzungsfonds of the Helmholtz Association (VH-NG-423).; National Science Foundation, ECCS-1201957 DMR-1151649 ; Deutscher Akademischer Austauschdienst, 2015 ID 5708457 ; GOA project; Fonds Wetenschappelijk Onderzoek, G.0044.13N ; Flemish Government; U.S. Department of Energy, DE-ACO2-98CH10886 ; Vernetzungsfonds of the Helmholtz Association, VH-NG-423 ; |
Approved |
Most recent IF: 4.279 |
| Call Number |
EMAT @ emat @ c:irua:142346UA @ admin @ c:irua:142346 |
Serial |
4553 |
| Permanent link to this record |
| |
|
| |
| Author |
Guzzinati, G.; Béché, A.; Lourenço-Martins, H.; Martin, J.; Kociak, M.; Verbeeck, J. |
| Title |
Probing the symmetry of the potential of localized surface plasmon resonances with phase-shaped electron beams |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
| Volume |
8 |
Issue |
8 |
Pages |
14999 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| Abstract |
Plasmonics, the science and technology of the interaction of light with metallic objects, is fundamentally changing the way we can detect, generate and manipulate light. Although the field is progressing swiftly, thanks to the availability of nanoscale manufacturing and analysis methods, fundamental properties such as the plasmonic excitations’ symmetries cannot be accessed directly, leading to a partial, sometimes incorrect, understanding of their properties. Here we overcome this limitation by deliberately shaping the wave function of an electron beam to match a plasmonic excitations’ symmetry in a modified transmission electron microscope. We show experimentally and theoretically that this offers selective detection of specific plasmon modes within metallic nanoparticles, while excluding modes with other symmetries. This method resembles the widespread use of polarized light for the selective excitation of plasmon modes with the advantage of locally probing the response of individual plasmonic objects and a far wider range of symmetry selection criteria. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000399084300001 |
Publication Date |
2017-04-12 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
12.124 |
Times cited |
84 |
Open Access |
OpenAccess |
| Notes |
; We thank F.J. Garcia de Abajo and D.M. Ugarte for interesting and fruitful discussion. This work was supported by funding from the European Research Council under the 7th Framework Program (FP7) ERC Starting Grant 278510 VORTEX. Financial support from the European Union under the Framework 7 program under a contract for an Integrated Infrastructure Initiative (Reference number 312483 ESTEEM2) is also gratefully acknowledged. Aluminum nanostructures were fabricated using the Nanomat nanofabrication facility. ; |
Approved |
Most recent IF: 12.124 |
| Call Number |
EMAT @ emat @ c:irua:142205UA @ admin @ c:irua:142205 |
Serial |
4548 |
| Permanent link to this record |
| |
|
| |
| Author |
Liao, Z.; Gauquelin, N.; Green, R.J.; Macke, S.; Gonnissen, J.; Thomas, S.; Zhong, Z.; Li, L.; Si, L.; Van Aert, S.; Hansmann, P.; Held, K.; Xia, J.; Verbeeck, J.; Van Tendeloo, G.; Sawatzky, G.A.; Koster, G.; Huijben, M.; Rijnders, G. |
| Title |
Thickness dependent properties in oxide heterostructures driven by structurally induced metal-oxygen hybridization variations |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
| Volume |
27 |
Issue |
17 |
Pages |
1606717 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| Abstract |
Thickness-driven electronic phase transitions are broadly observed in different types of functional perovskite heterostructures. However, uncertainty remains whether these effects are solely due to spatial confinement, broken symmetry, or rather to a change of structure with varying film thickness. Here, this study presents direct evidence for the relaxation of oxygen-2p and Mn-3d orbital (p-d) hybridization coupled to the layer-dependent octahedral tilts within a La2/3Sr1/3MnO3 film driven by interfacial octahedral coupling. An enhanced Curie temperature is achieved by reducing the octahedral tilting via interface structure engineering. Atomically resolved lattice, electronic, and magnetic structures together with X-ray absorption spectroscopy demonstrate the central role of thickness-dependent p-d hybridization in the widely observed dimensionality effects present in correlated oxide heterostructures. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000400449200011 |
Publication Date |
2017-03-15 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1616-301x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
12.124 |
Times cited |
55 |
Open Access |
|
| Notes |
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 No. NMP3-LA-2010-246102 IFOX. J.V. and S.V.A. acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (Grant Nos. 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 No. 278510 VORTEX. N.G., J.G., S.V.A., 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 was 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. |
Approved |
Most recent IF: 12.124 |
| Call Number |
UA @ admin @ c:irua:152640 |
Serial |
5367 |
| Permanent link to this record |
| |
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| |
| 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. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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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 |
| 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 |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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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 |
| |
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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 |
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Thesis |
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| Publisher |
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Place of Publication |
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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 |
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. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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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 |
| Permanent link to this record |
| |
|
| |
| 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 |
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| Corporate Author |
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Thesis |
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| Publisher |
Springer international publishing ag |
Place of Publication |
Cham |
Editor |
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| Language |
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Wos |
000391178900006 |
Publication Date |
2016-11-21 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| 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 |
; ; |
Approved |
Most recent IF: 4.033 |
| Call Number |
UA @ lucian @ c:irua:139930UA @ admin @ c:irua:139930 |
Serial |
4443 |
| Permanent link to this record |
| |
|
| |
| Author |
Conings, B.; Babayigit, A.; Klug, M. T.; Bai, S.; Gauquelin, N.; Sakai, N.; Wang, J. T.-W.; Verbeeck, J.; Boyen, H.-G. |
| Title |
A Universal Deposition Protocol for Planar Heterojunction Solar Cells with High Efficiency Based on Hybrid Lead Halide Perovskite Families |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
| Volume |
28 |
Issue |
28 |
Pages |
10701-10709 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| Abstract |
A robust and expedient gas quenching method is developed for the solution deposition of hybrid perovskite thin films. The method offers a reliable standard practice for the fabrication of a non-exhaustive variety of perovskites exhibiting excellent film morphology and commensurate high performance in both regular and inverted structured solar cell architectures. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Wos |
000392728200014 |
Publication Date |
2016-10-17 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1521-4095 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
19.791 |
Times cited |
95 |
Open Access |
|
| 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 Imec and FWO. M.T.K. acknowledges funding from the EPSRC project EP/M024881/1 “Organic-inorganic Perovskite Hybrid Tandem Solar Cells”. S.B. is a VINNMER Fellow and Marie Skłodowska-Curie Fellow. 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. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. The authors thank Johnny Baccus and Jan Mertens for technical support.; ECASJO_; |
Approved |
Most recent IF: 19.791; 2016 IF: NA |
| Call Number |
EMAT @ emat @ c:irua:138597 |
Serial |
4318 |
| Permanent link to this record |
| |
|
| |
| Author |
van den Bos, K.H.W.; Krause, F.F.; Béché, A.; Verbeeck, J.; Rosenauer, A.; Van Aert, S. |
| Title |
Locating light and heavy atomic column positions with picometer precision using ISTEM |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
| Volume |
172 |
Issue |
172 |
Pages |
75-81 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Recently, imaging scanning transmission electron microscopy (ISTEM) has been proposed as a promising new technique combining the advantages of conventional TEM (CTEM) and STEM [1]. The ability to visualize light and heavy elements together makes it a particularly interesting new, spatially incoherent imaging mode. Here, we evaluate this technique in term of precision with which atomic column locations can be measured. By using statistical parameter estimation theory, we will show that these locations can be accurately measured with a precision in the picometer range. Furthermore, a quantitative comparison is made with HAADF STEM imaging to investigate the advantages of ISTEM. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
|
| Language |
|
Wos |
000390600200009 |
Publication Date |
2016-10-09 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.843 |
Times cited |
8 |
Open Access |
|
| Notes |
The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0368.15N, G.0369.15N), and by a Ph.D. grant to K.H.W. van den Bos. The research leading to these results has received funding from the Deutsche Forschungsgemeinschaft under Contract No. RO 2057/4-2 and the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2. We thank Prof. G. Koster from the University of Twente for kindly providing us with the PbTiO3 test sample. |
Approved |
Most recent IF: 2.843 |
| Call Number |
EMAT @ emat @ c:irua:136109UA @ admin @ c:irua:136109 |
Serial |
4288 |
| Permanent link to this record |
| |
|
| |
| Author |
Juchtmans, R.; Guzzinati, G.; Verbeeck, J. |
| Title |
Extension of Friedel's law to vortex-beam diffraction |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Physical Review A |
Abbreviated Journal |
Phys Rev A |
| Volume |
94 |
Issue |
94 |
Pages |
033858 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Friedel's law states that the modulus of the Fourier transform of real functions is centrosymmetric, while the phase is antisymmetric. As a consequence of this, elastic scattering of plane-wave photons or electrons within the first-order Born-approximation, as well as Fraunhofer diffraction on any aperture, is bound to result in centrosymmetric diffraction patterns. Friedel's law, however, does not apply for vortex beams, and centrosymmetry in general is not present in their diffraction patterns. In this work we extend Friedel's law for vortex beams by showing that the diffraction patterns of vortex beams with opposite topological charge, scattered on the same two-dimensional potential, always are centrosymmetric to one another, regardless of the symmetry of the scattering object. We verify our statement by means of numerical simulations and experimental data. Our research provides deeper understanding in vortex-beam diffraction and can be used to design new experiments to measure the topological charge of vortex beams with diffraction gratings or to study general vortex-beam diffraction. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
|
| Language |
|
Wos |
000384374500010 |
Publication Date |
2016-09-30 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9926 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.925 |
Times cited |
13 |
Open Access |
|
| Notes |
The authors acknowledge support from the FWO (Aspirant Fonds Wetenschappelijk Onderzoek – Vlaanderen) and the EU under the Seventh Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative, Reference No. 312483-ESTEEM2 and ERC Starting Grant No. 278510 VORTEX.; ECASJO_; |
Approved |
Most recent IF: 2.925 |
| Call Number |
EMAT @ emat @ c:irua:137200UA @ admin @ c:irua:137200 |
Serial |
4314 |
| Permanent link to this record |
| |
|
| |
| Author |
Sankaran, K.J.; Hoang, D.Q.; Srinivasu, K.; Korneychuk, S.; Turner, S.; Drijkoningen, S.; Pobedinskas, P.; Verbeeck, J.; Leou, K.C.; Lin, I.N.; Haenen, K. |
| Title |
|
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Physica status solidi : A : applications and materials science |
Abbreviated Journal |
Phys Status Solidi A |
| Volume |
213 |
Issue |
10 |
Pages |
2654-2661 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Utilization of Au and nanocrystalline diamond ( NCD) as interlayers noticeably modifies the microstructure and field electron emission ( FEE) properties of hexagonal boron nitride nanowalls ( hBNNWs) grown on Si substrates. The FEE properties of hBNNWs on Au could be turned on at a low turn-on field of 14.3V mu m(-1), attaining FEE current density of 2.58mAcm(-2) and life-time stability of 105 min. Transmission electron microscopy reveals that the Au-interlayer nucleates the hBN directly, preventing the formation of amorphous boron nitride ( aBN) in the interface, resulting in enhanced FEE properties. But Au forms as droplets on the Si substrate forming again aBN at the interface. Conversely, hBNNWs on NCD shows superior in life-time stability of 287 min although it possesses inferior FEE properties in terms of larger turn-on field and lower FEE current density as compared to that of hBNNWs-Au. The uniform and continuous NCD film on Si also circumvents the formation of aBN phases and allows hBN to grow directly on NCD. Incorporation of carbon in hBNNWs from the NCD-interlayer improves the conductivity of hBNNWs, which assists in transporting the electrons efficiently from NCD to hBNNWs that results in better field emission of electrons with high life-time stability. (C) 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000388321500017 |
Publication Date |
2016-09-27 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1862-6300 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.775 |
Times cited |
5 |
Open Access |
|
| Notes |
The authors like to thank the financial support of the Research Foundation Flanders (FWO) via Research Projects G.0456.12 and G.0044.13N, the Methusalem “NANO” network. K. J. Sankaran, P. Pobedinskas, and S. Turner are FWO Postdoctoral Fellows of the Research Foundations Flanders (FWO). |
Approved |
Most recent IF: 1.775 |
| Call Number |
UA @ lucian @ c:irua:144644UA @ admin @ c:irua:144644 |
Serial |
4655 |
| Permanent link to this record |
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|
| |
| Author |
Lubk, A.; Vogel, K.; Wolf, D.; Krehl, J.; Röder, F.; Clark, L.; Guzzinati, G.; Verbeeck, J. |
| Title |
Fundamentals of Focal Series Inline Electron Holography |
Type |
H1 Book chapter |
| Year |
2016 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics / Hawkes, P.W. [edit.] |
Abbreviated Journal |
|
| Volume |
|
Issue |
|
Pages |
105-147 |
| Keywords |
H1 Book chapter; Electron microscopy for materials research (EMAT) |
| Abstract |
|
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
Elsevier BV |
Place of Publication |
|
Editor |
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| Language |
|
Wos |
|
Publication Date |
2016-09-24 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1076-5670; http://id.crossref.org/isbn/9780128048115 |
ISBN |
9780128048115 |
Additional Links |
UA library record |
| Impact Factor |
|
Times cited |
|
Open Access |
|
| Notes |
L.C., G.G., and J.V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant no. 278510 VORTEX. A.L., K.V., J. K., D.W., and F.R. acknowledge funding from the DIP of the Deutsche Forschungsgesellschaft.; ECASJO_; |
Approved |
Most recent IF: NA |
| Call Number |
EMAT @ emat @ c:irua:140097UA @ admin @ c:irua:140097 |
Serial |
4419 |
| Permanent link to this record |
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|
| |
| Author |
Sankaran, K.J.; Duc Quang Hoang; Korneychuk, S.; Kunuku, S.; Thomas, J.P.; Pobedinskas, P.; Drijkoningen, S.; Van Bael, M.K.; D'Haen, J.; Verbeeck, J.; Leou, K.-C.; Leung, K.T.; Lin, I.-N.; Haenen, K. |
| Title |
Hierarchical hexagonal boron nitride nanowall-diamond nanorod heterostructures with enhanced optoelectronic performance |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
| Volume |
6 |
Issue |
93 |
Pages |
90338-90346 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
A superior field electron emission (FEE) source made from a hierarchical heterostructure, where two-dimensional hexagonal boron nitride (hBN) nanowalls were coated on one-dimensional diamond nanorods (DNRs), is fabricated using a simple and scalable method. FEE characteristics of hBN-DNR display a low turn-on field of 6.0 V mu m(-1), a high field enhancement factor of 5870 and a high life-time stability of 435 min. Such an enhancement in the FEE properties of hBN-DNR derives from the distinctive material combination, i.e., high aspect ratio of the heterostructure, good electron transport from the DNR to the hBN nanowalls and efficient field emission of electrons from the hBN nanowalls. The prospective application of these heterostructures is further evidenced by enhanced microplasma devices using hBN-DNR as a cathode, in which the threshold voltage was lowered to 350 V, affirming the role of hBN-DNR in the improvement of electron emission. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Wos |
000385451800044 |
Publication Date |
2016-09-12 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2046-2069 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.108 |
Times cited |
8 |
Open Access |
|
| Notes |
The authors like to thank the financial support of the Research Foundation Flanders (FWO) via Research Projects G.0456.12 and G.0044.13N, the Methusalem “NANO” network. KJ Sankaran, and P Pobedinskas are Postdoctoral Fellows of the Research Foundation-Flanders (FWO). |
Approved |
Most recent IF: 3.108 |
| Call Number |
UA @ lucian @ c:irua:144757UA @ admin @ c:irua:144757 |
Serial |
4662 |
| Permanent link to this record |
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| |
| Author |
Juchtmans, R.; Clark, L.; Lubk, A.; Verbeeck, J. |
| Title |
Spiral phase plate contrast in optical and electron microscopy |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Physical review A |
Abbreviated Journal |
Phys Rev A |
| Volume |
94 |
Issue |
94 |
Pages |
023838 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The use of phase plates in the back focal plane of a microscope is a well-established technique in optical microscopy to increase the contrast of weakly interacting samples and is gaining interest in electron microscopy as well. In this paper we study the spiral phase plate (SPP), also called helical, vortex, or two-dimensional Hilbert phase plate, which adds an angularly dependent phase of the form exp(iℓϕk) to the exit wave in Fourier space. In the limit of large collection angles, we analytically calculate that the average of a pair of l=+-1
SPP filtered images is directly proportional to the gradient squared of the exit wave, explaining the edge contrast previously seen in optical SPP work. We discuss the difference between a clockwise-anticlockwise pair of SPP filtered images and derive conditions under which the modulus of the wave's gradient can be seen directly from one SPP filtered image. This work provides the theoretical background to interpret images obtained with a SPP, thereby opening new perspectives for new experiments to study, for example, magnetic materials in an electron microscope. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000381882800011 |
Publication Date |
2016-08-22 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9926 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.925 |
Times cited |
10 |
Open Access |
|
| Notes |
The authors acknowledge support from the FWO (Aspirant Fonds Wetenschappelijk Onderzoek – Vlaanderen) and the EU under the Seventh Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative, Reference No. 312483-ESTEEM2 and ERC Starting Grant No. 278510 VORTEX.; ECASJO_ |
Approved |
Most recent IF: 2.925 |
| Call Number |
EMAT @ emat @ c:irua:140086 |
Serial |
4418 |
| Permanent link to this record |
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| |
| Author |
Balasubramaniam, Y.; Pobedinskas, P.; Janssens, S.D.; Sakr, G.; Jomard, F.; Turner, S.; Lu, Y.G.; Dexters, W.; Soltani, A.; Verbeeck, J.; Barjon, J.; Nesládek, M.; Haenen, K.; |
| Title |
Thick homoepitaxial (110)-oriented phosphorus-doped n-type diamond |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
109 |
Issue |
109 |
Pages |
062105 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The fabrication of n-type diamond is essential for the realization of electronic components for extreme environments. We report on the growth of a 66 mu m thick homoepitaxial phosphorus-doped diamond on a (110)-oriented diamond substrate, grown at a very high deposition rate of 33 mu m h(-1). A pristine diamond lattice is observed by high resolution transmission electron microscopy, which indicates the growth of high quality diamond. About 2.9 x 10(16) cm(-3) phosphorus atoms are electrically active as substitutional donors, which is 60% of all incorporated dopant atoms. These results indicate that P-doped (110)-oriented diamond films deposited at high growth rates are promising candidates for future use in high-power electronic applications. Published by AIP Publishing. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
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Wos |
000383183600025 |
Publication Date |
2016-08-11 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.411 |
Times cited |
20 |
Open Access |
|
| Notes |
This work was financially supported by the EU through the FP7 Collaborative Project “DIAMANT,” the “H2020 Research and Innovation Action Project” “GreenDiamond” (No. 640947), and the Research Foundation-Flanders (FWO) (Nos. G.0C02.15N and VS.024.16N). J.V. acknowledges funding from the “Geconcentreerde Onderzoekacties” (GOA) project “Solarpaint” of the University of Antwerp. The TEM instrument was partly funded by the Hercules fund from the Flemish Government. We particularly thank Dr. J. E. Butler (Naval Research Laboratory, USA) for the sample preparation by laser slicing for TEM analysis, Dr. J. Pernot (Universite Grenoble Alpes/CNRS-Institut Neel, France) for helpful discussions, Ms. C. Vilar (Universite de Versailles St. Quentin en Yvelines, France) for technical help on SEM-CL experiments, and Dr. S. S. Nicley (Hasselt University, Belgium) for improving the language of the text. P.P. and S.T. are Postdoctoral Fellows of the Research Foundation-Flanders (FWO). |
Approved |
Most recent IF: 3.411 |
| Call Number |
UA @ lucian @ c:irua:137160 |
Serial |
4407 |
| Permanent link to this record |
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| |
| Author |
Sankaran, K.J.; Hoang, D.Q.; Kunuku, S.; Korneychuk, S.; Turner, S.; Pobedinskas, P.; Drijkoningen, S.; Van Bael, M.K.; D' Haen, J.; Verbeeck, J.; Leou, K.-C.; Lin, I.-N.; Haenen, K. |
| Title |
Enhanced optoelectronic performances of vertically aligned hexagonal boron nitride nanowalls-nanocrystalline diamond heterostructures |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
| Volume |
6 |
Issue |
6 |
Pages |
29444 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| Abstract |
Field electron emission (FEE) properties of vertically aligned hexagonal boron nitride nanowalls (hBNNWs) grown on Si have been markedly enhanced through the use of nitrogen doped nanocrystalline diamond (nNCD) films as an interlayer. The FEE properties of hBNNWs-nNCD heterostructures show a low turn-on field of 15.2 V/mum, a high FEE current density of 1.48 mA/cm(2) and life-time up to a period of 248 min. These values are far superior to those for hBNNWs grown on Si substrates without the nNCD interlayer, which have a turn-on field of 46.6 V/mum with 0.21 mA/cm(2) FEE current density and life-time of 27 min. Cross-sectional TEM investigation reveals that the utilization of the diamond interlayer circumvented the formation of amorphous boron nitride prior to the growth of hexagonal boron nitride. Moreover, incorporation of carbon in hBNNWs improves the conductivity of hBNNWs. Such a unique combination of materials results in efficient electron transport crossing nNCD-to-hBNNWs interface and inside the hBNNWs that results in enhanced field emission of electrons. The prospective application of these materials is manifested by plasma illumination measurements with lower threshold voltage (370 V) and longer life-time, authorizing the role of hBNNWs-nNCD heterostructures in the enhancement of electron emission. |
| Address |
IMOMEC, IMEC vzw, 3590 Diepenbeek, Belgium |
| Corporate Author |
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Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
English |
Wos |
000379391000001 |
Publication Date |
2016-07-12 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| 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 |
15 |
Open Access |
|
| Notes |
The authors like to thank the financial support of the Research Foundation Flanders (FWO) via Research Project G.0456.12, G0044.13N and the Methusalem “NANO” network. Kamatchi Jothiramalingam Sankaran, Stuart Turner, and Paulius Pobedinskas are Postdoctoral Fellows of the Research Foundations Flanders (FWO). |
Approved |
Most recent IF: 4.259 |
| Call Number |
c:irua:134643 c:irua:134643UA @ admin @ c:irua:134643 |
Serial |
4119 |
| Permanent link to this record |
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| |
| Author |
Liao, Z; , Green, R.J; Gauquelin, N; Macke, S.; Li, L.; Gonnissen, J; Sutarto, R.; Houwman, E.P.; Zhong, Z.; Van Aert, S.; Verbeeck, J.; Sawatzky, G.A.; Huijben, M.; Koster, G.; Rijnders, G. |
| Title |
Long-Range Domain Structure and Symmetry Engineering by Interfacial Oxygen Octahedral Coupling at Heterostructure Interface |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
| Volume |
26 |
Issue |
26 |
Pages |
6627-6634 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| Abstract |
In epitaxial thin film systems, the crystal structure and its symmetry deviate from the bulk counterpart due to various mechanisms such as epitaxial strain and interfacial structural coupling, which is accompanyed by a change in their properties. In perovskite materials, the crystal symmetry can be described by rotations of sixfold coordinated transition metal oxygen octahedra, which are found to be altered at interfaces. Here, it is unraveled how the local oxygen octahedral coupling at perovskite heterostructural interfaces strongly influences the domain structure and symmetry of the epitaxial films resulting in design rules to induce various structures in thin films using carefully selected combinations of substrate/buffer/film. Very interestingly it is discovered that these combinations lead to structure changes throughout the full thickness of the film. The results provide a deep insight into understanding the origin of induced structures in a perovskite heterostructure and an intelligent route to achieve unique functional properties. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000384809800010 |
Publication Date |
2016-06-23 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1616-301x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
12.124 |
Times cited |
23 |
Open Access |
|
| Notes |
We thank B. Keimer for valuable discussions. 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. and S.V.A. acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0044.13N, G.0374.13N, G.0368.15N, 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., J.G., S.V.A., 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.; esteem2jra2; esteem2jra3; ECASJO_; |
Approved |
Most recent IF: 12.124 |
| Call Number |
EMAT @ emat @ c:irua:144663UA @ admin @ c:irua:144663 |
Serial |
4106 |
| Permanent link to this record |
| |
|
| |
| Author |
Clark, L.; Guzzinati, G.; Béché, A.; Lubk, A.; Verbeeck, J. |
| Title |
Symmetry-constrained electron vortex propagation |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Physical review A |
Abbreviated Journal |
Phys Rev A |
| Volume |
93 |
Issue |
93 |
Pages |
063840 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Electron vortex beams hold great promise for development in transmission electron microscopy but have yet to be widely adopted. This is partly due to the complex set of interactions that occur between a beam carrying orbital angular momentum (OAM) and a sample. Herein, the system is simplified to focus on the interaction between geometrical symmetries, OAM, and topology. We present multiple simulations alongside experimental data to study the behavior of a variety of electron vortex beams after interacting with apertures of different symmetries and investigate the effect on their OAM and vortex structure, both in the far field and under free-space propagation. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000378197200006 |
Publication Date |
2016-06-23 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9926 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.925 |
Times cited |
7 |
Open Access |
|
| Notes |
L.C., A.B., G.G., and J.V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant No. 278510—VORTEX. J.V. and A.L. acknowledge financial support from the European Union through the 7th Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative (Reference No. 312483 ESTEEM2). The Qu-Ant-EM microscope was partly funded by the Hercules fund of the Flemish Government.; esteem2jra3; ECASJO; |
Approved |
Most recent IF: 2.925 |
| Call Number |
c:irua:134086 c:irua:134086 |
Serial |
4090 |
| Permanent link to this record |
