|
Records |
|
Author |
Wang, A.; Chen, F.R.; Van Aert, S.; van Dyck, D. |
|
Title |
Direct structure inversion from exit waves: part 1: theory and simulations |
Type |
A1 Journal article |
|
Year |
2010 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
Volume |
110 |
Issue |
5 |
Pages |
527-534 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
Abstract |
In order to interpret the amplitude and phase of the exit wave in terms of mass and position of the atoms, one has to invert the dynamic scattering of the electrons in the object so as to obtain a starting structure which can then be used as a seed for further quantitative structure refinement. This is especially challenging in case of a zone axis condition when the interaction of the electrons with the atom column is very strong. Based on the channelling theory we will show that the channelling map not only yields a circle on the Argand plot but also a circular defocus curve for every column. The former gives the number of atoms in each column, while the latter provides the defocus value for each column, which reveals the surface roughness at the exit plane with single atom sensitivity. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
Language |
|
Wos |
000279065700019 |
Publication Date |
2009-12-12 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.843 |
Times cited |
25 |
Open Access |
|
|
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2010 IF: 2.063 |
|
Call Number |
UA @ lucian @ c:irua:83691 |
Serial |
723 |
Permanent link to this record |
|
|
|
|
Author |
van Thiel, T. c.; Brzezicki, W.; Autieri, C.; Hortensius, J. r.; Afanasiev, D.; Gauquelin, N.; Jannis, D.; Janssen, N.; Groenendijk, D. j.; Fatermans, J.; Van Aert, S.; Verbeeck, J.; Cuoco, M.; Caviglia, A. d. |
|
Title |
Coupling Charge and Topological Reconstructions at Polar Oxide Interfaces |
Type |
A1 Journal article |
|
Year |
2021 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys Rev Lett |
|
Volume |
127 |
Issue |
12 |
Pages |
127202 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
In oxide heterostructures, different materials are integrated into a single artificial crystal, resulting in a breaking of inversion symmetry across the heterointerfaces. A notable example is the interface between polar and nonpolar materials, where valence discontinuities lead to otherwise inaccessible charge and spin states. This approach paved the way for the discovery of numerous unconventional properties absent in the bulk constituents. However, control of the geometric structure of the electronic wave functions in correlated oxides remains an open challenge. Here, we create heterostructures consisting of ultrathin SrRuO3, an itinerant ferromagnet hosting momentum-space sources of Berry curvature, and
LaAlO3, a polar wide-band-gap insulator. Transmission electron microscopy reveals an atomically sharp LaO/RuO2/SrO interface configuration, leading to excess charge being pinned near the LaAlO3/SrRuO3 interface. We demonstrate through magneto-optical characterization, theoretical calculations and transport measurements that the real-space charge reconstruction drives a reorganization of the topological charges in the band structure, thereby modifying the momentum-space Berry curvature in SrRuO3. Our results illustrate how the topological and magnetic features of oxides can be manipulated by engineering charge discontinuities at oxide interfaces. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000704665000010 |
Publication Date |
2021-09-16 |
|
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 |
17 |
Open Access |
OpenAccess |
|
Notes |
The authors thank E. Lesne, M. Lee, H. Barakov, M. Matthiesen and U. Filippozzi for discussions. The authors are grateful to E.J.S. van Thiel for producing the illustration in Fig. 4a. This work was supported by the European Research Council under the European Unions Horizon 2020 programme/ERC Grant agreements No. [677458], [770887] and No. [731473] (Quantox of QuantERA ERA-NET Cofund in Quantum Technologies) and by the Netherlands Organisation for Scientific Research (NWO/OCW) as part of the Frontiers of Nanoscience (NanoFront) and VIDI program. The authors acknowledge funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. [823717] – ESTEEM3. N. G., J. V., and S. V. A. acknowledge funding from the University of Antwerp through the Concerted Research Actions (GOA) project Solarpaint and the TOP project. C. A. and W. B. are supported by the Foundation for Polish Science through the International Research Agendas program co-financed by the European Union within the Smart Growth Operational Programme. C. A. acknowledges access to the computing facilities of the Interdisciplinary Center of Modeling at the University of Warsaw, Grant No. G73-23 and G75-10. W.B. acknowledges support from the Narodowe Centrum Nauk (NCN, National Science Centre, Poland) Project No. 2019/34/E/ST3/00404'; esteem3TA; esteem3reported |
Approved |
Most recent IF: 8.462 |
|
Call Number |
EMAT @ emat @c:irua:182595 |
Serial |
6824 |
Permanent link to this record |
|
|
|
|
Author |
Martinez, G.T.; van den Bos, K.H.W.; Alania, M.; Nellist, P.D.; Van Aert, S. |
|
Title |
Thickness dependence of scattering cross-sections in quantitative scanning transmission electron microscopy |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
Volume |
187 |
Issue |
|
Pages |
84-92 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
In quantitative scanning transmission electron microscopy (STEM), scattering cross-sections have been shown to be very sensitive to the number of atoms in a column and its composition. They correspond to the integrated intensity over the atomic column and they outperform other measures. As compared to atomic column peak intensities, which saturate at a given thickness, scattering cross-sections increase monotonically. A study of the electron wave propagation is presented to explain the sensitivity of the scattering cross-sections. Based on the multislice algorithm, we analyse the wave propagation inside the crystal and its link to the scattered signal for the different probe positions contained in the scattering cross-section for detector collection in the low-, middle- and high-angle regimes. The influence to the signal from scattering of neighbouring columns is also discussed. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000428131200011 |
Publication Date |
2018-01-31 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.843 |
Times cited |
4 |
Open Access |
Not_Open_Access: Available from 01.02.2020
|
|
Notes |
The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings ( G.0374.13N , G.0369.15N , G.0368.15N and WO.010.16N ) and a PhD grant to K.H.W.v.d.B. The research leading to these results has received funding from the European Union 7th Framework Programme [ FP7 /2007-2013] under Grant agreement no. 312483 (ESTEEM2). The authors are grateful to A. Rosenauer for providing access to the StemSim software. |
Approved |
Most recent IF: 2.843 |
|
Call Number |
EMAT @ emat @c:irua:149384 |
Serial |
4809 |
Permanent link to this record |
|
|
|
|
Author |
Schryvers, D.; Shi, H.; Martinez, G.T.; Van Aert, S.; Frenzel, J.; Van Humbeeck, J. |
|
Title |
Nano- and microcrystal investigations of precipitates, interfaces and strain fields in Ni-Ti-Nb by various TEM techniques |
Type |
P1 Proceeding |
|
Year |
2013 |
Publication |
Materials science forum
T2 – 9th European Symposium on Martensitic Transformations (ESOMAT 2012), SEP 09-16, 2012, St Petersburg, RUSSIA |
Abbreviated Journal |
|
|
Volume |
738/739 |
Issue |
|
Pages |
65-71 |
|
Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
|
Abstract |
In the present contribution several advanced electron microscopy techniques are employed in order to describe chemical and structural features of the nano- and microstructure of a Ni45.5Ti45.5Nb9 alloy. A line-up of Nb-rich nano-precipitates is found in the Ni-Ti-rich austenite of as-cast material. Concentration changes of the matrix after annealing are correlated with changes in the transformation temperatures. The formation of rows and plates of larger Nb-rich precipitates and particles is described. The interaction of a twinned martensite plate with a Nb-rich nano-precipitate is discussed and the substitution of Nb atoms on the Ti-sublattice in the matrix is confirmed. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
|
Language |
|
Wos |
000316089000011 |
Publication Date |
2013-03-11 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1662-9752; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
|
Times cited |
2 |
Open Access |
|
|
Notes |
Fwo |
Approved |
Most recent IF: NA |
|
Call Number |
UA @ lucian @ c:irua:104692 |
Serial |
2247 |
Permanent link to this record |
|
|
|
|
Author |
de Backer, A.; Martinez, G.T.; Rosenauer, A.; Van Aert, S. |
|
Title |
Atom counting in HAADF STEM using a statistical model-based approach : methodology, possibilities, and inherent limitations |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
Volume |
134 |
Issue |
|
Pages |
23-33 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
In the present paper, a statistical model-based method to count the number of atoms of monotype crystalline nanostructures from high resolution high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM) images is discussed in detail together with a thorough study on the possibilities and inherent limitations. In order to count the number of atoms, it is assumed that the total scattered intensity scales with the number of atoms per atom column. These intensities are quantitatively determined using model-based statistical parameter estimation theory. The distribution describing the probability that intensity values are generated by atomic columns containing a specific number of atoms is inferred on the basis of the experimental scattered intensities. Finally, the number of atoms per atom column is quantified using this estimated probability distribution. The number of atom columns available in the observed STEM image, the number of components in the estimated probability distribution, the width of the components of the probability distribution, and the typical shape of a criterion to assess the number of components in the probability distribution directly affect the accuracy and precision with which the number of atoms in a particular atom column can be estimated. It is shown that single atom sensitivity is feasible taking the latter aspects into consideration. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
Language |
|
Wos |
000324474900005 |
Publication Date |
2013-05-17 |
|
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 |
48 |
Open Access |
|
|
Notes |
FWO; Esteem2; FP 2007-2013; esteem2_jra2 |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
|
Call Number |
UA @ lucian @ c:irua:109916 |
Serial |
162 |
Permanent link to this record |
|
|
|
|
Author |
Gonnissen, J.; De Backer, A.; den Dekker, A.J.; Sijbers, J.; Van Aert, S. |
|
Title |
Detecting and locating light atoms from high-resolution STEM images: The quest for a single optimal design |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
Volume |
170 |
Issue |
170 |
Pages |
128-138 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
Abstract |
In the present paper, the optimal detector design is investigated for both detecting and locating light atoms from high resolution scanning transmission electron microscopy (HR STEM) images. The principles of detection theory are used to quantify the probability of error for the detection of light atoms from HR STEM images. To determine the optimal experiment design for locating light atoms, use is made of the so-called Cramer-Rao Lower Bound (CRLB). It is investigated if a single optimal design can be found for both the detection and location problem of light atoms. Furthermore, the incoming electron dose is optimised for both research goals and it is shown that picometre range precision is feasible for the estimation of the atom positions when using an appropriate incoming electron dose under the optimal detector settings to detect light atoms. |
|
Address |
Electron Microscopy for Materials Science (EMAT), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. Electronic address: sandra.vanaert@uantwerpen.be |
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
English |
Wos |
000386925500014 |
Publication Date |
2016-07-26 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.843 |
Times cited |
6 |
Open Access |
|
|
Notes |
The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0368.15, G.0369.15 and G.0374.13) and a postdoctoral research grant to A. De Backer. The research leading to these results has also received funding from the European Union Seventh Framework Programme [FP7/2007-2013] under Grant agreement no. 312483 (ESTEEM2). The authors would also like to thank A. Rosenauer for providing access to the STEMsim software and Gerardo T. Martinez for fruitful discussions.; esteem2_jra2 |
Approved |
Most recent IF: 2.843 |
|
Call Number |
c:irua:135337 c:irua:135337 |
Serial |
4128 |
Permanent link to this record |
|
|
|
|
Author |
de Backer, A.; De wael, A.; Gonnissen, J.; Van Aert, S. |
|
Title |
Optimal experimental design for nano-particle atom-counting from high-resolution STEM images |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
Volume |
151 |
Issue |
151 |
Pages |
46-55 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
In the present paper, the principles of detection theory are used to quantify the probability of error for atom-counting from high resolution scanning transmission electron microscopy (HR STEM) images. Binary and multiple hypothesis testing have been investigated in order to determine the limits to the precision with which the number of atoms in a projected atomic column can be estimated. The probability of error has been calculated when using STEM images, scattering cross-sections or peak intensities as a criterion to count atoms. Based on this analysis, we conclude that scattering cross-sections perform almost equally well as images and perform better than peak intensities. Furthermore, the optimal STEM detector design can be derived for atom-counting using the expression for the probability of error. We show that for very thin objects LAADF is optimal and that for thicker objects the optimal inner detector angle increases. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
Language |
|
Wos |
000351237800007 |
Publication Date |
2014-11-11 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.843 |
Times cited |
24 |
Open Access |
|
|
Notes |
312483 Esteem2; Fwo G039311; G037413; esteem2_jra2 |
Approved |
Most recent IF: 2.843; 2015 IF: 2.436 |
|
Call Number |
c:irua:123926 c:irua:123926 |
Serial |
2481 |
Permanent link to this record |
|
|
|
|
Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
|
Title |
Atom counting |
Type |
H2 Book chapter |
|
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
Volume |
|
Issue |
|
Pages |
91-144 |
|
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab |
|
Abstract |
In this chapter, a statistical model-based method to count the number of atoms of monotype crystalline nanostructures from high-resolution annular dark-field (ADF) scanning transmission electron microscopy (STEM) images is discussed in detail together with a thorough study on the possibilities and inherent limitations. We show that this method can be applied to nanocrystals of arbitrary shape, size, and atom type. The validity of the atom-counting results is confirmed by means of detailed image simulations and it is shown that the high sensitivity of our method enables us to count atoms with single atom sensitivity. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
|
Publication Date |
2021-03-06 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
217 |
Series Issue |
|
Edition |
|
|
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
|
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
Call Number |
UA @ admin @ c:irua:177529 |
Serial |
6776 |
Permanent link to this record |
|
|
|
|
Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
|
Title |
Optimal experiment design for nanoparticle atom counting from ADF STEM images |
Type |
H2 Book chapter |
|
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
Volume |
|
Issue |
|
Pages |
145-175 |
|
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab |
|
Abstract |
In this chapter, the principles of detection theory are used to quantify the probability of error for atom counting from high-resolution scanning transmission electron microscopy (HRSTEM) images. Binary and multiple hypothesis testing have been investigated in order to determine the limits to the precision with which the number of atoms in a projected atomic column can be estimated. The probability of error has been calculated when using STEM images, scattering cross-sections or peak intensities as a criterion to count atoms. Based on this analysis, we conclude that scattering cross-sections perform almost equally well as images and perform better than peak intensities. Furthermore, the optimal STEM detector design can be derived for atom counting using the expression of the probability of error. We show that for very thin objects the low-angle annular dark-field (LAADF) regime is optimal and that for thicker objects the optimal inner detector angle increases. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
|
Publication Date |
2021-03-06 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
217 |
Series Issue |
|
Edition |
|
|
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
|
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
Call Number |
UA @ admin @ c:irua:177530 |
Serial |
6785 |
Permanent link to this record |
|
|
|
|
Author |
de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S. |
|
Title |
Statistical parameter estimation theory : principles and simulation studies |
Type |
H2 Book chapter |
|
Year |
2021 |
Publication |
Advances in imaging and electron physics
T2 – Advances in imaging and electron physics |
Abbreviated Journal |
|
|
Volume |
|
Issue |
|
Pages |
29-72 |
|
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab |
|
Abstract |
In this chapter, the principles of statistical parameter estimation theory for a quantitative analysis of atomic-resolution electron microscopy images are introduced. Within this framework, electron microscopy images are described by a parametric statistical model. Here, parametric models are introduced for different types of electron microscopy images: reconstructed exit waves, annular dark-field (ADF) scanning transmission electron microscopy (STEM) images, and simultaneously acquired ADF and annular bright-field (ABF) STEM images. Furthermore, the Cramér-Rao lower bound (CRLB) is introduced, i.e. a theoretical lower bound on the variance of any unbiased estimator. This CRLB is used to quantify the precision of the structure parameters of interest, such as the atomic column positions and the integrated atomic column intensities. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
|
Publication Date |
2021-03-06 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
217 |
Series Issue |
|
Edition |
|
|
ISSN |
|
ISBN |
978-0-12-824607-8; 1076-5670 |
Additional Links |
UA library record |
|
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
Notes |
ERC Consolidator project funded by the European Union grant #770887 Picometrics |
Approved |
Most recent IF: NA |
|
Call Number |
UA @ admin @ c:irua:177527 |
Serial |
6788 |
Permanent link to this record |
|
|
|
|
Author |
Şentürk, D.G.; De Backer, A.; Van Aert, S. |
|
Title |
Element specific atom counting for heterogeneous nanostructures: Combining multiple ADF STEM images for simultaneous thickness and composition determination |
Type |
A1 Journal Article |
|
Year |
2024 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
Volume |
259 |
Issue |
|
Pages |
113941 |
|
Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
|
Abstract |
In this paper, a methodology is presented to count the number of atoms in heterogeneous nanoparticles based on the combination of multiple annular dark field scanning transmission electron microscopy (ADF STEM) images. The different non-overlapping annular detector collection regions are selected based on the principles of optimal statistical experiment design for the atom-counting problem. To count the number of atoms, the total intensities of scattered electrons for each atomic column, the so-called scattering cross-sections, are simultaneously compared with simulated library values for the different detector regions by minimising the squared differences. The performance of the method is evaluated for simulated Ni@Pt and Au@Ag core-shell nanoparticles. Our approach turns out to be a dose efficient alternative for the investigation of beam-sensitive heterogeneous materials as compared to the combination of ADF STEM and energy dispersive X-ray spectroscopy. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
|
Publication Date |
2024-02-19 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record |
|
Impact Factor |
2.2 |
Times cited |
|
Open Access |
OpenAccess |
|
Notes |
This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0346.21N, GOA7723N, and EOS 40007495) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF). |
Approved |
Most recent IF: 2.2; 2024 IF: 2.843 |
|
Call Number |
EMAT @ emat @c:irua:204353 |
Serial |
8996 |
Permanent link to this record |
|
|
|
|
Author |
Boschker, H.; Huijben, M.; Vailinois, A.; Verbeeck, J.; Van Aert, S.; Luysberg, M.; Bals, S.; Van Tendeloo, G.; Houwman, E.P.; Koster, G.; Blank, D.H.A.; Rijnders, G. |
|
Title |
Optimized fabrication of high-quality La0.67Sr0.33MnO3 thin films considering all essential characteristics |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
|
Volume |
44 |
Issue |
20 |
Pages |
205001-205001,9 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
In this paper, an overview of the fabrication and properties of high-quality La0.67Sr0.33MnO3 (LSMO) thin films is given. A high-quality LSMO film combines a smooth surface morphology with a large magnetization and a small residual resistivity, while avoiding precipitates and surface segregation. In the literature, typically only a few of these issues are adressed. We therefore present a thorough characterization of our films, which were grown by pulsed laser deposition. The films were characterized with reflection high energy electron diffraction, atomic force microscopy, x-ray diffraction, magnetization and transport measurements, x-ray photoelectron spectroscopy and scanning transmission electron microscopy. The films have a saturation magnetization of 4.0 µB/Mn, a Curie temperature of 350 K and a residual resistivity of 60 µΩ cm. These results indicate that high-quality films, combining both large magnetization and small residual resistivity, were realized. A comparison between different samples presented in the literature shows that focussing on a single property is insufficient for the optimization of the deposition process. For high-quality films, all properties have to be adressed. For LSMO devices, the thin-film quality is crucial for the device performance. Therefore, this research is important for the application of LSMO in devices. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
London |
Editor |
|
|
Language |
|
Wos |
000290150900001 |
Publication Date |
2011-04-29 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0022-3727;1361-6463; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.588 |
Times cited |
99 |
Open Access |
|
|
Notes |
This research was financially supported by the Dutch Science Foundation, by NanoNed, a nanotechnology program of the Dutch Ministry of Economic Affairs, and by the NanOxide program of the European Science Foundation. This work is supported in part by the Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering, under contract DE-AC02-76SF00515. |
Approved |
Most recent IF: 2.588; 2011 IF: 2.544 |
|
Call Number |
UA @ lucian @ c:irua:89557UA @ admin @ c:irua:89557 |
Serial |
2491 |
Permanent link to this record |
|
|
|
|
Author |
de Backer, A.; Van Aert, S.; van Dyck, D. |
|
Title |
High precision measurements of atom column positions using model-based exit wave reconstruction |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
Volume |
111 |
Issue |
9/10 |
Pages |
1475-1482 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
Abstract |
In this paper, it has been investigated how to measure atom column positions as accurately and precisely as possible using a focal series of images. In theory, it is expected that the precision would considerably improve using a maximum likelihood estimator based on the full series of focal images. As such, the theoretical lower bound on the variances of the unknown atom column positions can be attained. However, this approach is numerically demanding. Therefore, maximum likelihood estimation has been compared with the results obtained by fitting a model to a reconstructed exit wave rather than to the full series of focal images. Hence, a real space model-based exit wave reconstruction technique based on the channelling theory is introduced. Simulations show that the reconstructed complex exit wave contains the same amount of information concerning the atom column positions as the full series of focal images. Only for thin samples, which act as weak phase objects, this information can be retrieved from the phase of the reconstructed complex exit wave. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
Language |
|
Wos |
000300461200004 |
Publication Date |
2011-07-28 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.843 |
Times cited |
8 |
Open Access |
|
|
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
|
Call Number |
UA @ lucian @ c:irua:91879 |
Serial |
1438 |
Permanent link to this record |
|
|
|
|
Author |
Alania, M.; De Backer, A.; Lobato, I.; Krause, F.F.; Van Dyck, D.; Rosenauer, A.; Van Aert, S. |
|
Title |
How precise can atoms of a nanocluster be located in 3D using a tilt series of scanning transmission electron microscopy images? |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
Volume |
181 |
Issue |
181 |
Pages |
134-143 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
Abstract |
In this paper, we investigate how precise atoms of a small nanocluster can ultimately be located in three dimensions (3D) from a tilt series of images acquired using annular dark field (ADF) scanning transmission electron microscopy (STEM). Therefore, we derive an expression for the statistical precision with which the 3D atomic position coordinates can be estimated in a quantitative analysis. Evaluating this statistical precision as a function of the microscope settings also allows us to derive the optimal experimental design. In this manner, the optimal angular tilt range, required electron dose, optimal detector angles, and number of projection images can be determined. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000411170800016 |
Publication Date |
2016-12-15 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.843 |
Times cited |
3 |
Open Access |
OpenAccess |
|
Notes |
The authors acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative. Reference No. 312483-ESTEEM2. The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0369.15N, G.0368.15N, and WO.010.16N) and a post-doctoral grant to A. De Backer, and from the DFG under contract No. RO-2057/4-2. |
Approved |
Most recent IF: 2.843 |
|
Call Number |
EMAT @ emat @ c:irua:144432 |
Serial |
4618 |
Permanent link to this record |
|
|
|
|
Author |
Wang, A.; Van Aert, S.; Goos, P.; van Dyck, D. |
|
Title |
Precision of three-dimensional atomic scale measurements from HRTEM images : what are the limits? |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
Volume |
114 |
Issue |
|
Pages |
20-30 |
|
Keywords |
A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT); Vision lab |
|
Abstract |
In this paper, we investigate to what extent high resolution transmission electron microscopy images can be used to measure the mass, in terms of thickness, and surface profile, corresponding to the defocus offset, of an object at the atomic scale. Therefore, we derive an expression for the statistical precision with which these object parameters can be estimated in a quantitative analysis. Evaluating this expression as a function of the microscope settings allows us to derive the optimal microscope design. Acquiring three-dimensional structure information in terms of thickness turns out to be much more difficult than obtaining two-dimensional information on the projected atom column positions. The attainable precision is found to be more strongly affected by processes influencing the image contrast, such as phonon scattering, than by the specific choice of microscope settings. For a realistic incident electron dose, it is expected that atom columns can be distinguished with single atom sensitivity up to a thickness of the order of the extinction distance. A comparable thickness limit is determined to measure surface steps of one atom. An increase of the electron dose shifts the limiting thickness upward due to an increase in the signal-to-noise ratio. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
Language |
|
Wos |
000301954300003 |
Publication Date |
2012-01-06 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.843 |
Times cited |
5 |
Open Access |
|
|
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2012 IF: 2.470 |
|
Call Number |
UA @ lucian @ c:irua:94116 |
Serial |
2692 |
Permanent link to this record |
|
|
|
|
Author |
Hao, Y.; Velpula, G.; Kaltenegger, M.; Bodlos, W.R.; Vibert, F.; Mali, K.S.; De Feyter, S.; Resel, R.; Geerts, Y.H.; Van Aert, S.; Beljonne, D.; Lazzaroni, R. |
|
Title |
From 2D to 3D : bridging self-assembled monolayers to a substrate-induced polymorph in a molecular semiconductor |
Type |
A1 Journal article |
|
Year |
2022 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
|
Volume |
34 |
Issue |
5 |
Pages |
2238-2248 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
In this study, a new bottom-up approach is proposed to predict the crystal structure of the substrate-induced polymorph (SIP) of an archetypal molecular semiconductor. In spite of intense efforts, the formation mechanism of SIPs is still not fully understood, and predicting their crystal structure is a very delicate task. Here, we selected lead phthalocyanine (PbPc) as a prototypical molecular material because it is a highly symmetrical yet nonplanar molecule and we demonstrate that the growth and crystal structure of the PbPc SIPs can be templated by the corresponding physisorbed self-assembled molecular networks (SAMNs). Starting from SAMNs of PbPc formed at the solution/graphite interface, the structural and energetic aspects of the assembly were studied by a combination of in situ scanning tunneling microscopy and multiscale computational chemistry approach. Then, the growth of a PbPc SIP on top of the physisorbed monolayer was modeled without prior experimental knowledge, from which the crystal structure of the SIP was predicted. The theoretical prediction of the SIP was verified by determining the crystal structure of PbPc thin films using X-ray diffraction techniques, revealing the formation of a new polymorph of PbPc on the graphite substrate. This study clearly illustrates the correlation between the SAMNs and SIPs, which are traditionally considered as two separate but conceptually connected research areas. This approach is applicable to molecular materials in general to predict the crystal structure of their SIPs. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000812125800001 |
Publication Date |
2022-02-17 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0897-4756; 1520-5002 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
8.6 |
Times cited |
|
Open Access |
Not_Open_Access |
|
Notes |
|
Approved |
Most recent IF: 8.6 |
|
Call Number |
UA @ admin @ c:irua:189086 |
Serial |
7084 |
Permanent link to this record |
|
|
|
|
Author |
Delfino, C.L.; Hao, Y.; Martin, C.; Minoia, A.; Gopi, E.; Mali, K.S.; Van der Auweraer, M.; Geerts, Y.H.; Van Aert, S.; Lazzaroni, R.; De Feyter, S. |
|
Title |
Conformation-Dependent Monolayer and Bilayer Structures of an Alkylated TTF Derivative Revealed using STM and Molecular Modeling |
Type |
A1 Journal Article |
|
Year |
2023 |
Publication |
The Journal of Physical Chemistry C |
Abbreviated Journal |
J. Phys. Chem. C |
|
Volume |
127 |
Issue |
47 |
Pages |
23023-23033 |
|
Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
|
Abstract |
In this study, the multi-layer self-assembled molecular network formation of an alkylated tetrathiafulvalene compound is studied at the liquid-solid interface between 1-phenyloctane and graphite. A combined theoretical/experimental approach associating force-field and quantum-chemical calculations with scanning tunnelling microscopy is used to determine the two-dimensional self-assembly beyond the monolayer, but also to further the understanding of the molecular adsorption conformation and its impact on the molecular packing within the assemblies at the monolayer and bilayer level. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
001111637100001 |
Publication Date |
2023-11-30 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1932-7447 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
Impact Factor |
3.7 |
Times cited |
|
Open Access |
OpenAccess |
|
Notes |
Financial support from the Research Foundation-Flanders (FWO G081518N, G0A3220N) and KU Leuven–Internal Funds (C14/19/079) is acknowledged. This work was in part supported by FWO and F. R. S.-FNRS under the Excellence of Science EOS program (project 30489208 and 40007495). C.M. acknowledges the financial support: Grants PID2021-128761OA-C22 and CNS2022-136052 funded by MCIN/AEI/10.13039/501100011033 by the “European Union” and SBPLY/21/180501/000127 funded by JCCM and by the EU through “Fondo Europeo de Desarollo Regional” (FEDER). Research in Mons is also supported by the Belgian National Fund for Scientific Research (FRS-FNRS) within the Consortium des Équipements de Calcul Intensif – CÉCI, under Grant 2.5020.11, and by the Walloon Region (ZENOBE Tier-1 supercomputer, under grant 1117545). |
Approved |
Most recent IF: 3.7; 2023 IF: 4.536 |
|
Call Number |
EMAT @ emat @c:irua:201671 |
Serial |
8974 |
Permanent link to this record |
|
|
|
|
Author |
Friedrich, T.; Yu, C.-P.; Verbeeck, J.; Van Aert, S. |
|
Title |
Phase object reconstruction for 4D-STEM using deep learning |
Type |
A1 Journal article |
|
Year |
2023 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
|
|
Volume |
29 |
Issue |
1 |
Pages |
395-407 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
In this study, we explore the possibility to use deep learning for the reconstruction of phase images from 4D scanning transmission electron microscopy (4D-STEM) data. The process can be divided into two main steps. First, the complex electron wave function is recovered for a convergent beam electron diffraction pattern (CBED) using a convolutional neural network (CNN). Subsequently, a corresponding patch of the phase object is recovered using the phase object approximation. Repeating this for each scan position in a 4D-STEM dataset and combining the patches by complex summation yields the full-phase object. Each patch is recovered from a kernel of 3x3 adjacent CBEDs only, which eliminates common, large memory requirements and enables live processing during an experiment. The machine learning pipeline, data generation, and the reconstruction algorithm are presented. We demonstrate that the CNN can retrieve phase information beyond the aperture angle, enabling super-resolution imaging. The image contrast formation is evaluated showing a dependence on the thickness and atomic column type. Columns containing light and heavy elements can be imaged simultaneously and are distinguishable. The combination of super-resolution, good noise robustness, and intuitive image contrast characteristics makes the approach unique among live imaging methods in 4D-STEM. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
001033590800038 |
Publication Date |
2023-01-12 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1431-9276 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.8 |
Times cited |
1 |
Open Access |
OpenAccess |
|
Notes |
We acknowledge funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement no. 770887 PICOMETRICS) and funding from the European Union's Horizon 2020 research and innovation program under grant agreement No. 823717 ESTEEM3. J.V. and S.V.A acknowledge funding from the University of Antwerp through a TOP BOF project. The direct electron detector (Merlin, Medipix3, Quantum Detectors) was funded by the Hercules fund from the Flemish Government. This work was supported by the FWO and FNRS within the 2Dto3D project of the EOS program (grant number 30489208). |
Approved |
Most recent IF: 2.8; 2023 IF: 1.891 |
|
Call Number |
UA @ admin @ c:irua:198221 |
Serial |
8912 |
Permanent link to this record |
|
|
|
|
Author |
Gonnissen, J.; De Backer, A.; den Dekker, A.J.; Sijbers, J.; Van Aert, S. |
|
Title |
Atom-counting in High Resolution Electron Microscopy: TEM or STEM – that's the question |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
Volume |
174 |
Issue |
174 |
Pages |
112-120 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
|
Abstract |
In this work, a recently developed quantitative approach based on the principles of detection theory is used in order to determine the possibilities and limitations of High Resolution Scanning Transmission Electron Microscopy (HR STEM) and HR TEM for atom-counting. So far, HR STEM has been shown to be an appropriate imaging mode to count the number of atoms in a projected atomic column. Recently, it has been demonstrated that HR TEM, when using negative spherical aberration imaging, is suitable for atom-counting as well. The capabilities of both imaging techniques are investigated and compared using the probability of error as a criterion. It is shown that for the same incoming electron dose, HR STEM outperforms HR TEM under common practice standards, i.e. when the decision is based on the probability function of the peak intensities in HR TEM and of the scattering cross-sections in HR STEM. If the atom-counting decision is based on the joint probability function of the image pixel values, the dependence of all image pixel intensities as a function of thickness should be known accurately. Under this assumption, the probability of error may decrease significantly for atom-counting in HR TEM and may, in theory, become lower as compared to HR STEM under the predicted optimal experimental settings. However, the commonly used standard for atom-counting in HR STEM leads to a high performance and has been shown to work in practice. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000403342200013 |
Publication Date |
2016-10-27 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.843 |
Times cited |
2 |
Open Access |
|
|
Notes |
The authors gratefully acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0368.15N, G.0369.15N, G.0374.13N, and WO.010.16N) and a postdoctoral grant to A. De Backer. The research leading to these results has received funding from the European Union Seventh Framework Programme [FP7/2007-2013] under Grant agreement no. 312483 (ESTEEM2). |
Approved |
Most recent IF: 2.843 |
|
Call Number |
EMAT @ emat @ c:irua:137102 |
Serial |
4315 |
Permanent link to this record |
|
|
|
|
Author |
Ren, P.; Zhang, T.; Jain, N.; Ching, H.Y.V.; Jaworski, A.; Barcaro, G.; Monti, S.; Silvestre-Albero, J.; Celorrio, V.; Chouhan, L.; Rokicinska, A.; Debroye, E.; Kustrowski, P.; Van Doorslaer, S.; Van Aert, S.; Bals, S.; Das, S. |
|
Title |
An atomically dispersed Mn-photocatalyst for generating hydrogen peroxide from seawater via the Water Oxidation Reaction (WOR) |
Type |
A1 Journal article |
|
Year |
2023 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
|
|
Volume |
145 |
Issue |
30 |
Pages |
16584-16596 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Organic synthesis (ORSY); Theory and Spectroscopy of Molecules and Materials (TSM²) |
|
Abstract |
In this work, we have fabricatedan aryl amino-substitutedgraphiticcarbon nitride (g-C3N4) catalyst with atomicallydispersed Mn capable of generating hydrogen peroxide (H2O2) directly from seawater. This new catalyst exhibitedexcellent reactivity, obtaining up to 2230 & mu;M H2O2 in 7 h from alkaline water and up to 1800 & mu;Mfrom seawater under identical conditions. More importantly, the catalystwas quickly recovered for subsequent reuse without appreciable lossin performance. Interestingly, unlike the usual two-electron oxygenreduction reaction pathway, the generation of H2O2 was through a less common two-electron water oxidation reaction(WOR) process in which both the direct and indirect WOR processesoccurred; namely, photoinduced h(+) directly oxidized H2O to H2O2 via a one-step 2e(-) WOR, and photoinduced h(+) first oxidized a hydroxide (OH-) ion to generate a hydroxy radical ((OH)-O-& BULL;), and H2O2 was formed indirectly by thecombination of two (OH)-O-& BULL;. We have characterized thematerial, at the catalytic sites, at the atomic level using electronparamagnetic resonance, X-ray absorption near edge structure, extendedX-ray absorption fine structure, high-resolution transmission electronmicroscopy, X-ray photoelectron spectroscopy, magic-angle spinningsolid-state NMR spectroscopy, and multiscale molecular modeling, combiningclassical reactive molecular dynamics simulations and quantum chemistrycalculations. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
001034983300001 |
Publication Date |
2023-07-24 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0002-7863 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
15 |
Times cited |
21 |
Open Access |
Not_Open_Access |
|
Notes |
S.D. thanks the IOF grant and Francqui start up grant from the University of Antwerp, Belgium, for the financial support. P.R. thanks CSC and T.Z. thanks FWO for their financial assistance to finish this work. E.D. would like to thank the KU Leuven Research Fund for financial support through STG/21/010. J.S.A. acknowledges financial support from MCIN/AEI/10.13039/501100011033 and EU NextGeneration/PRTR (Project PCI2020-111968/3D-Photocat) and Diamond Synchrotron (rapid access proposal SP32609). This work was supported by the European Research Council (grant 770887-PICOMETRICS to S.V.A. and Grant 815128-REALNANO to S.B.). S.B. and S.V.A. acknowledge financial support from the Research Foundation Flanders (FWO, Belgium, project G.0346.21 N). We also thank Mr. Jian Zhu and Mr. Shahid Ullah Khan from the University of Antwerp, Belgium, for helpful discussions. |
Approved |
Most recent IF: 15; 2023 IF: 13.858 |
|
Call Number |
UA @ admin @ c:irua:198426 |
Serial |
8831 |
Permanent link to this record |
|
|
|
|
Author |
van den Broek, W.; Van Aert, S.; Goos, P.; van Dyck, D. |
|
Title |
Throughput maximization of particle radius measurements by balancing size and current of the electron probe |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
Volume |
111 |
Issue |
7 |
Pages |
940-947 |
|
Keywords |
A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT); Vision lab |
|
Abstract |
In thispaperweinvestigatewhichprobesizemaximizesthethroughputwhenmeasuringtheradiusof nanoparticlesinhighangleannulardarkfieldscanningtransmissionelectronmicroscopy(HAADFSTEM). The sizeandthecorrespondingcurrentoftheelectronprobedeterminetheprecisionoftheestimateofa particlesradius.Maximizingthroughputmeansthatamaximumnumberofparticlesshouldbeimaged withinagiventimeframe,sothataprespecifiedprecisionisattained.WeshowthatBayesianstatistical experimentaldesignisaveryusefulapproachtodeterminetheoptimalprobesizeusingacertainamount of priorknowledgeaboutthesample.Thedependenceoftheoptimalprobesizeonthedetectorgeometry and thediameter,variabilityandatomicnumberoftheparticlesisinvestigated.Anexpressionforthe optimalprobesizeintheabsenceofanykindofpriorknowledgeaboutthespecimenisderivedaswell. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
Language |
|
Wos |
000300461000026 |
Publication Date |
2010-11-25 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.843 |
Times cited |
7 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
|
Call Number |
UA @ lucian @ c:irua:89657 |
Serial |
3659 |
Permanent link to this record |
|
|
|
|
Author |
Liao, Z.; Gauquelin, N.; Green, R.J.; Müller-Caspary, K.; Lobato, I.; Li, L.; Van Aert, S.; Verbeeck, J.; Huijben, M.; Grisolia, M.N.; Rouco, V.; El Hage, R.; Villegas, J.E.; Mercy, A.; Bibes, M.; Ghosez, P.; Sawatzky, G.A.; Rijnders, G.; Koster, G. |
|
Title |
Metal–insulator-transition engineering by modulation tilt-control in perovskite nickelates for room temperature optical switching |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
America |
Abbreviated Journal |
P Natl Acad Sci Usa |
|
Volume |
115 |
Issue |
38 |
Pages |
9515-9520 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
In transition metal perovskites ABO3 the physical properties are largely driven by the rotations of the BO6 octahedra, which can be tuned in thin films through strain and dimensionality control. However, both approaches have fundamental and practical limitations due to discrete and indirect variations in bond angles, bond lengths and film symmetry by using commercially available substrates. Here, we introduce modulation tilt control as a new approach to tune the ground state of perovskite oxide thin films by acting explicitly on the oxygen octahedra rotation modes, i.e. directly on the bond angles. By intercalating the prototype SmNiO3 target material with a tilt-control layer, we cause the system to change the natural amplitude of a given rotation mode without affecting the interactions. In contrast to strain and dimensionality engineering, our method enables a continuous fine-tuning of the materials properties. This is achieved through two independent adjustable parameters: the nature of the tilt-control material (through its symmetry, elastic constants and oxygen rotation angles) and the relative thicknesses of the target and tilt-control materials. As a result, a magnetic and electronic phase diagram can be obtained, normally only accessible by A-site element substitution, within the single SmNiO3 compound. With this unique approach, we successfully adjusted the metal-insulator transition (MIT) to room temperature to fulfill the desired conditions for optical switching applications. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000447224900057 |
Publication Date |
2018-09-05 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0027-8424 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
9.661 |
Times cited |
50 |
Open Access |
OpenAccess |
|
Notes |
We would like to acknowledge Prof. Z. Zhong for stimulated discussion. M.H., G.K. and G.R. acknowledge funding from DESCO program of the Dutch Foundation for Fundamental Research on Matter (FOM) with financial support from the Netherlands Organization for Scientific Research (NWO). This work was funded by the European Union Council under the 7th Framework Program (FP7) grant nr NMP3-LA-2010-246102 IFOX. J.V., S.V.A, N.G. and K.M.C. acknowledge funding from FWO projects G.0044.13N, G.0374.13N, G. 0368.15N, and G.0369.15N. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. N.G. and J.V. acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483- ESTEEM2). The Canadian work was supported by NSERC and the Max Planck-UBC Centre for Quantum Materials. Some experiments for this work were performed at the Canadian Light Source, which is funded by the Canada Foundation for Innovation, NSERC, the National Research Council of Canada, the Canadian Institutes of Health Research, the Government of Saskatchewan, Western Economic Diversification Canada, and the University of Saskatchewan. MB acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC CoG grant MINT #615759. A.M. and Ph.G. were supported by the ARC project AIMED and F.R.S-FNRS PDR project HiT4FiT and acknowledge access to Céci computing facilities funded by F.R.S-FNRS (Grant No 2.5020.1), Tier-1 supercomputer of the Fédération Wallonie-Bruxelles funded by the Walloon Region (Grant No 1117545) and HPC resources from the PRACE project Megapasta. |
Approved |
Most recent IF: 9.661 |
|
Call Number |
EMAT @ emat @c:irua:154784UA @ admin @ c:irua:154784 |
Serial |
5059 |
Permanent link to this record |
|
|
|
|
Author |
Zhang, Z.; Lobato, I.; Brown, H.; Jannis, D.; Verbeeck, J.; Van Aert, S.; Nellist, P. |
|
Title |
Generalised oscillator strength for core-shell electron excitation by fast electrons based on Dirac solutions |
Type |
Dataset |
|
Year |
2023 |
Publication |
|
Abbreviated Journal |
|
|
Volume |
|
Issue |
|
Pages |
|
|
Keywords |
Dataset; Electron microscopy for materials research (EMAT) |
|
Abstract |
Inelastic excitation as exploited in Electron Energy Loss Spectroscopy (EELS) contains a rich source of information that is revealed in the scattering process. To accurately quantify core-loss EELS, it is common practice to fit the observed spectrum with scattering cross-sections calculated using experimental parameters and a Generalized Oscillator Strength (GOS) database [1]. The GOS is computed using Fermi’s Golden Rule and orbitals of bound and excited states. Previously, the GOS was based on Hartree-Fock solutions [2], but more recently Density Functional Theory (DFT) has been used [3]. In this work, we have chosen to use the Dirac equation to incorporate relativistic effects and have performed calculations using Flexible Atomic Code (FAC) [4]. This repository contains a tabulated GOS database based on Dirac solutions for computing double differential cross-sections under experimental conditions. We hope the Dirac-based GOS database can benefit the EELS community for both academic use and industry integration. Database Details: – Covers all elements (Z: 1-108) and all edges – Large energy range: 0.01 – 4000 eV – Large momentum range: 0.05 -50 Å-1 – Fine log sampling: 128 points for energy and 256 points for momentum – Data format: GOSH [3] Calculation Details: – Single atoms only; solid-state effects are not considered – Unoccupied states before continuum states of ionization are not considered; no fine structure – Plane Wave Born Approximation – Frozen Core Approximation is employed; electrostatic potential remains unchanged for orthogonal states when – core-shell electron is excited – Self-consistent Dirac–Fock–Slater iteration is used for Dirac calculations; Local Density Approximation is assumed for electron exchange interactions; continuum states are normalized against asymptotic form at large distances – Both large and small component contributions of Dirac solutions are included in GOS – Final state contributions are included until the contribution of the previous three states falls below 0.1%. A convergence log is provided for reference. Version 1.1 release note: – Update to be consistent with GOSH data format [3], all the edges are now within a single hdf5 file. A notable change in particular, the sampling in momentum is in 1/m, instead of previously in 1/Å. Great thanks to Gulio Guzzinati for his suggestions and sending conversion script. Version 1.2 release note: – Add “File Type / File version” information [1] Verbeeck, J., and S. Van Aert. Ultramicroscopy 101.2-4 (2004): 207-224. [2] Leapman, R. D., P. Rez, and D. F. Mayers. The Journal of Chemical Physics 72.2 (1980): 1232-1243. [3] Segger, L, Guzzinati, G, & Kohl, H. Zenodo (2023). doi:10.5281/zenodo.7645765 [4] Gu, M. F. Canadian Journal of Physics 86(5) (2008): 675-689. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
|
Publication Date |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record |
|
Impact Factor |
|
Times cited |
|
Open Access |
Not_Open_Access |
|
Notes |
|
Approved |
Most recent IF: NA |
|
Call Number |
UA @ admin @ c:irua:203392 |
Serial |
9042 |
Permanent link to this record |
|
|
|
|
Author |
Schryvers, D.; Van Aert, S.; Delville, R.; Idrissi, H.; Turner, S.; Salje, E.K.H. |
|
Title |
Dedicated TEM on domain boundaries from phase transformations and crystal growth |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
Phase transitions |
Abbreviated Journal |
Phase Transit |
|
Volume |
86 |
Issue |
1 |
Pages |
15-22 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
Investigating domain boundaries and their effects on the behaviour of materials automatically implies the need for detailed knowledge on the structural aspects of the atomic configurations at these interfaces. Not only in view of nearest neighbour interactions but also at a larger scale, often surpassing the unit cell, the boundaries can contain structural elements that do not exist in the bulk. In the present contribution, a number of special boundaries resulting from phase transformations or crystal growth and those recently investigated by advanced transmission electron microscopy techniques in different systems will be reviewed. These include macrotwins between microtwinned martensite plates in NiAl, austenite-single variant martensite habit planes in low hysteresis NiTiPd, nanotwins in non-textured nanostructured Pd and ferroelastic domain boundaries in CaTiO3. In all discussed cases these boundaries play an essential role in the properties of the respective materials. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
New York |
Editor |
|
|
Language |
|
Wos |
000312586700003 |
Publication Date |
2012-12-19 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0141-1594;1029-0338; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
1.06 |
Times cited |
|
Open Access |
|
|
Notes |
Fwo; Iap |
Approved |
Most recent IF: 1.06; 2013 IF: 1.044 |
|
Call Number |
UA @ lucian @ c:irua:101222 |
Serial |
612 |
Permanent link to this record |
|
|
|
|
Author |
Jones, L.; Yang, H.; Pennycook, T.J.; Marshall, M.S.J.; Van Aert, S.; Browning, N.D.; Castell, M.R.; Nellist, P.D. |
|
Title |
Smart Align : a new tool for robust non-rigid registration of scanning microscope data |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Advanced Structural and Chemical Imaging |
Abbreviated Journal |
|
|
Volume |
1 |
Issue |
1 |
Pages |
8 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
Many microscopic investigations of materials may benefit from the recording of multiple successive images. This can include techniques common to several types of microscopy such as frame averaging to improve signal-to-noise ratios (SNR) or time series to study dynamic processes or more specific applications. In the scanning transmission electron microscope, this might include focal series for optical sectioning or aberration measurement, beam damage studies or camera-length series to study the effects of strain; whilst in the scanning tunnelling microscope, this might include bias-voltage series to probe local electronic structure. Whatever the application, such investigations must begin with the careful alignment of these data stacks, an operation that is not always trivial. In addition, the presence of low-frequency scanning distortions can introduce intra-image shifts to the data. Here, we describe an improved automated method of performing non-rigid registration customised for the challenges unique to scanned microscope data specifically addressing the issues of low-SNR data, images containing a large proportion of crystalline material and/or local features of interest such as dislocations or edges. Careful attention has been paid to artefact testing of the non-rigid registration method used, and the importance of this registration for the quantitative interpretation of feature intensities and positions is evaluated. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000218507000008 |
Publication Date |
2015-07-09 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
2198-0926; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
|
Times cited |
131 |
Open Access |
|
|
Notes |
312483 Esteem2; esteem2_jra2 |
Approved |
Most recent IF: NA |
|
Call Number |
c:irua:126944 c:irua:126944 |
Serial |
3043 |
Permanent link to this record |
|
|
|
|
Author |
Grünewald, L.; Chezganov, D.; De Meyer, R.; Orekhov, A.; Van Aert, S.; Bogaerts, A.; Bals, S.; Verbeeck, J. |
|
Title |
In Situ Plasma Studies Using a Direct Current Microplasma in a Scanning Electron Microscope |
Type |
A1 Journal Article |
|
Year |
2024 |
Publication |
Advanced Materials Technologies |
Abbreviated Journal |
Adv Materials Technologies |
|
Volume |
|
Issue |
|
Pages |
|
|
Keywords |
A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; |
|
Abstract |
Microplasmas can be used for a wide range of technological applications and to improve the understanding of fundamental physics. Scanning electron microscopy, on the other hand, provides insights into the sample morphology and chemistry of materials from the mm‐ down to the nm‐scale. Combining both would provide direct insight into plasma‐sample interactions in real‐time and at high spatial resolution. Up till now, very few attempts in this direction have been made, and significant challenges remain. This work presents a stable direct current glow discharge microplasma setup built inside a scanning electron microscope. The experimental setup is capable of real‐time in situ imaging of the sample evolution during plasma operation and it demonstrates localized sputtering and sample oxidation. Further, the experimental parameters such as varying gas mixtures, electrode polarity, and field strength are explored and experimental<italic>V</italic>–<italic>I</italic>curves under various conditions are provided. These results demonstrate the capabilities of this setup in potential investigations of plasma physics, plasma‐surface interactions, and materials science and its practical applications. The presented setup shows the potential to have several technological applications, for example, to locally modify the sample surface (e.g., local oxidation and ion implantation for nanotechnology applications) on the µm‐scale. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
001168639900001 |
Publication Date |
2024-02-25 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
2365-709X |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
Impact Factor |
6.8 |
Times cited |
|
Open Access |
OpenAccess |
|
Notes |
L.G., S.B., and J.V. acknowledge support from the iBOF-21-085 PERsist research fund. D.C., S.V.A., and J.V. acknowledge funding from a TOPBOF project of the University of Antwerp (FFB 170366). R.D.M., A.B., and J.V. acknowledge funding from the Methusalem project of the University of Antwerp (FFB 15001A, FFB 15001C). A.O. and J.V. acknowledge funding from the Research Foundation Flanders (FWO, Belgium) project SBO S000121N. |
Approved |
Most recent IF: 6.8; 2024 IF: NA |
|
Call Number |
EMAT @ emat @c:irua:204363 |
Serial |
8995 |
Permanent link to this record |
|
|
|
|
Author |
Bals, S.; Goris, B.; Altantzis, T.; Heidari, H.; Van Aert, S.; Van Tendeloo, G. |
|
Title |
Seeing and measuring in 3D with electrons |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
Comptes rendus : physique |
Abbreviated Journal |
Cr Phys |
|
Volume |
15 |
Issue |
2-3 |
Pages |
140-150 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
Modern TEM enables the investigation of nanostructures at the atomic scale. However, TEM images are only two-dimensional (2D) projections of a three-dimensional (3D) object. Electron tomography can overcome this limitation. The technique is increasingly focused towards quantitative measurements and reaching atomic resolution in 3D has been the ultimate goal for many years. Therefore, one needs to optimize the acquisition of the data, the 3D reconstruction techniques as well as the quantification methods. Here, we will review a broad range of methodologies and examples. Finally, we will provide an outlook and will describe future challenges in the field of electron tomography. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Paris |
Editor |
|
|
Language |
|
Wos |
000334013600005 |
Publication Date |
2014-01-20 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1631-0705; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.048 |
Times cited |
15 |
Open Access |
OpenAccess |
|
Notes |
(FWO;Belgium); European Research Council under the 7th Framework Program (FP7); ERC grant No.246791 – COUNTATOMS; ERC grant No.335078 – COLOURATOMS; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); |
Approved |
Most recent IF: 2.048; 2014 IF: 2.035 |
|
Call Number |
UA @ lucian @ c:irua:113855 |
Serial |
2960 |
Permanent link to this record |
|
|
|
|
Author |
Jany, B.R.; Gauquelin, N.; Willhammar, T.; Nikiel, M.; van den Bos, K.H.W.; Janas, A.; Szajna, K.; Verbeeck, J.; Van Aert, S.; Van Tendeloo, G.; Krok, F. |
|
Title |
Controlled growth of hexagonal gold nanostructures during thermally induced self-assembling on Ge(001) surface |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
|
Volume |
7 |
Issue |
7 |
Pages |
42420 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
Nano-sized gold has become an important material in various fields of science and technology, where control over the size and crystallography is desired to tailor the functionality. Gold crystallizes in the face-centered cubic (fcc) phase, and its hexagonal closed packed (hcp) structure is a very unusual and rare phase. Stable Au hcp phase has been reported to form in nanoparticles at the tips of some Ge nanowires. It has also recently been synthesized in the form of thin graphene-supported sheets which are unstable under electron beam irradiation. Here, we show that stable hcp Au 3D nanostructures with well-defined crystallographic orientation and size can be systematically created in a process of thermally induced self-assembly of thin Au layer on Ge(001) monocrystal. The Au hcp crystallite is present in each Au nanostructure and has been characterized by different electron microscopy techniques. We report that a careful heat treatment above the eutectic melting temperature and a controlled cooling is required to form the hcp phase of Au on a Ge single crystal. This new method gives scientific prospects to obtain stable Au hcp phase for future applications in a rather simple manner as well as redefine the phase diagram of Gold with Germanium. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000393940700001 |
Publication Date |
2017-02-14 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
4.259 |
Times cited |
25 |
Open Access |
OpenAccess |
|
Notes |
The authors gratefully acknowledge the financial support from the Polish National Science Center, grant no. DEC-2012/07/B/ST5/00906. N.G., G.V.T. and J.V. acknowledge the European Union (EU) Council under the 7th Framework Program (FP7) ERC Starting Grant 278510 VORTEX for support. The Research Foundation Flanders is acknowledged through project fundings (G.0374.13N, G.0368.15N, G.0369.15N) and for a Ph.D. research grant to K.H.W.v.d.B. The microscope was partly funded by the Hercules Fund from the Flemish Government. T.W. acknowledges the Swedish Research Council for an international postdoc grant. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483–ESTEEM2 (Integrated Infrastructure Initiative–I3). Part of the research was carried out with equipment purchased with financial support from the European Regional Development Fund in the framework of the Polish Innovation Economy Operational Program (Contract No. POIG.02.01.00-12-023/08). |
Approved |
Most recent IF: 4.259 |
|
Call Number |
EMAT @ emat @ c:irua:140846UA @ admin @ c:irua:140846 |
Serial |
4423 |
Permanent link to this record |
|
|
|
|
Author |
Shi, H.; Frenzel, J.; Martinez, G.T.; Van Rompaey, S.; Bakulin, A.; Kulkova, A.; Van Aert, S.; Schryvers, D. |
|
Title |
Site occupation of Nb atoms in ternary Ni-Ti-Nb shape memory alloys |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
Acta materialia |
Abbreviated Journal |
Acta Mater |
|
Volume |
74 |
Issue |
|
Pages |
85-95 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
Nb occupancy in the austenite B2-NiTi matrix and Ti2Ni phase in NiTiNb shape memory alloys was investigated by aberration-corrected scanning transmission electron microscopy and precession electron diffraction. In both cases, Nb atoms were found to prefer to occupy the Ti rather than Ni sites. A projector augmented wave method within density functional theory was used to calculate the atomic and electronic structures of the austenitic B2-NiTi matrix phase and the Ti2Ni precipitates both with and without addition of Nb. The obtained formation energies and analysis of structural and electronic characteristics explain the preference for Ti sites for Nb over Ni sites. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
|
Language |
|
Wos |
000338621400009 |
Publication Date |
2014-05-08 |
|
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 |
21 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 5.301; 2014 IF: 4.465 |
|
Call Number |
UA @ lucian @ c:irua:118334 |
Serial |
3028 |
Permanent link to this record |
|
|
|
|
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 |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000411170800022 |
Publication Date |
2017-06-03 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.843 |
Times cited |
34 |
Open Access |
OpenAccess |
|
Notes |
The authors acknowledge financial support from Flanders (FWO, Belgium) through project fundings (G.0044.13N, G.0374.13N, G.0368.15N, G.0369.15N), and by a Ph.D. grant to K.H.W.v.d.B. The Qu-Ant-EM microscope used for this study was partly funded by the Hercules fund from the Flemish Government. A.B. and N.G. acknowledge the EUROTAPES project (FP7-NMP.2011.2.2-1 Grant no.280432) which partly funded this study. N.G., A.B. and J.V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. The research leading to these results has received funding from the Deutsche Forschungsgemeinschaft under Contract No. RO 2057/4-2 and the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2. We thank Prof. G. Koster from the University of Twente for kindly providing us with the LSMO-NGO test sample. |
Approved |
Most recent IF: 2.843 |
|
Call Number |
EMAT @ emat @ c:irua:144435UA @ admin @ c:irua:144435 |
Serial |
4620 |
Permanent link to this record |