| Records |
| Author |
den Dekker, A.J.; Gonnissen, J.; de Backer, A.; Sijbers, J.; Van Aert, S. |
| Title |
Estimation of unknown structure parameters from high-resolution (S)TEM images : what are the limits? |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
| Volume |
134 |
Issue |
|
Pages |
34-43 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract  |
Statistical parameter estimation theory is proposed as a quantitative method to measure unknown structure parameters from electron microscopy images. Images are then purely considered as data planes from which structure parameters have to be determined as accurately and precisely as possible using a parametric statistical model of the observations. For this purpose, an efficient algorithm is proposed for the estimation of atomic column positions and intensities from high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) images. Furthermore, the so-called CramérRao lower bound (CRLB) is reviewed to determine the limits to the precision with which continuous parameters such as atomic column positions and intensities can be estimated. Since this lower bound can only be derived for continuous parameters, alternative measures using the principles of detection theory are introduced for problems concerning the estimation of discrete parameters such as atomic numbers. An experimental case study is presented to show the practical use of these measures for the optimization of the experiment design if the purpose is to decide between the presence of specific atom types using STEM images. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| Language |
|
Wos |
000324474900006 |
Publication Date |
2013-06-01 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.843 |
Times cited |
31 |
Open Access |
|
| Notes |
FWO; FP 2007-2013; Esteem2; esteem2_jra2 |
Approved |
Most recent IF: 2.843; 2013 IF: 2.745 |
| Call Number |
UA @ lucian @ c:irua:109240 |
Serial |
1083 |
| Permanent link to this record |
| |
|
| |
| Author |
Sliem, M.A.; Turner, S.; Heeskens, D.; Kalidindi, S.B.; Van Tendeloo, G.; Muhler, M.; Fischer, R.A. |
| Title |
Preparation, microstructure characterization and catalytic performance of Cu/ZnO and ZnO/Cu composite nanoparticles for liquid phase methanol synthesis |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
| Volume |
14 |
Issue |
22 |
Pages |
8170-8178 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Stearate@Cu/ZnO nanocomposite particles with molar ratios of ZnO ∶ Cu = 2 and 5 are synthesized by reduction of the metalorganic Cu precursor [Cu{(OCH(CH3)CH2N(CH3)2)}2] in the presence of stearate@ZnO nanoparticles. In the case of ZnO ∶ Cu = 5, high-angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) combined with electron-energy-loss-spectroscopy (EELS) as well as attenuated total reflection Fourier transform infrared (ATR-IR) spectroscopy are used to localize the small amount of Cu deposited on the surface of 35 nm sized stearate@ZnO particles. For ZnO ∶ Cu = 2, the microstructure of the nanocomposites after catalytic activity testing is characterized by HAADF-STEM techniques. This reveals the construction of large Cu nanoparticles (2050 nm) decorated by small ZnO nanoparticles (35 nm). The catalytic activity of both composites for the synthesis of methanol from syn gas is evaluated. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
| Language |
|
Wos |
000304102200033 |
Publication Date |
2012-04-16 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1463-9076;1463-9084; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.123 |
Times cited |
16 |
Open Access |
|
| Notes |
Fwo |
Approved |
Most recent IF: 4.123; 2012 IF: 3.829 |
| Call Number |
UA @ lucian @ c:irua:98377 |
Serial |
2702 |
| Permanent link to this record |
| |
|
| |
| Author |
Velazco, A.; Nord, M.; Béché, A.; Verbeeck, J. |
| Title |
Evaluation of different rectangular scan strategies for STEM imaging |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
| Volume |
|
Issue |
|
Pages |
113021 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
STEM imaging is typically performed by raster scanning a focused electron probe over a sample. Here we investigate and compare three different scan patterns, making use of a programmable scan engine that allows to arbitrarily set the sequence of probe positions that are consecutively visited on the sample. We compare the typical raster scan with a so-called ‘snake’ pattern where the scan direction is reversed after each row and a novel Hilbert scan pattern that changes scan direction rapidly and provides an homogeneous treatment of both scan directions. We experimentally evaluate the imaging performance on a single crystal test sample by varying dwell time and evaluating behaviour with respect to sample drift. We demonstrate the ability of the Hilbert scan pattern to more faithfully represent the high frequency content of the image in the presence of sample drift. It is also shown that Hilbert scanning provides reduced bias when measuring lattice parameters from the obtained scanned images while maintaining similar precision in both scan directions which is especially important when e.g. performing strain analysis. Compared to raster scanning with flyback correction, both snake and Hilbert scanning benefit from dose reduction as only small probe movement steps occur. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000544042800007 |
Publication Date |
2020-05-21 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0304-3991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.2 |
Times cited |
13 |
Open Access |
OpenAccess |
| Notes |
A.V., A.B. and J.V. acknowledge funding through FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy') from the Flanders Research Fund. M.N. received support for this work from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 838001. J.V acknowledges funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. |
Approved |
Most recent IF: 2.2; 2020 IF: 2.843 |
| Call Number |
EMAT @ emat @c:irua:169225 |
Serial |
6369 |
| Permanent link to this record |
| |
|
| |
| Author |
Schneidewind, U.; Haest, P.J.; Atashgahi, S.; Seuntjens, P.; et al. |
| Title |
Kinetics of dechlorination by Dehalococcoides mccartyi using different carbon sources |
Type |
A1 Journal article |
| Year |
2014 |
Publication |
Journal of contaminant hydrology |
Abbreviated Journal |
|
| Volume |
157 |
Issue |
|
Pages |
25-36 |
| Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
| Abstract |
Stimulated anaerobic dechlorination is generally considered a valuable step for the remediation of aquifers polluted with chlorinated ethenes (CEs). Correct simulation and prediction of this process in situ, however, require good knowledge of the associated biological reactions. The aim of this study was to evaluate the dechlorination reaction in an aquifer contaminated with trichloroethene (TCE) and its daughter products, discharging into the Zenne River. Different carbon sources were used in batch cultures and these were related to the dechlorination reaction, together with the monitored biomarkers. Appropriate kinetic formulations were assessed. Reductive dechlorination of TCE took place only when external carbon sources were added to microcosms, and occurred concomitant with a pronounced increase in the Dehalococcoides mccartyi cell count as determined by 16S rRNA gene-targeted qPCR. This indicates that native dechlorinating bacteria are present in the aquifer of the Zenne site and that the oligotrophic nature of the aquifer prevents a complete degradation to ethene. The type of carbon source, the cell number of D. mccartyi or the reductive dehalogenase genes, however, did not unequivocally explain the observed differences in degradation rates or the extent of dechlorination. Neither first-order, Michaelis-Menten nor Monod kinetics could perfectly simulate the dechlorination reactions in TCE spiked microcosms. A sensitivity analysis indicated that the inclusion of donor limitation would not significantly enhance the simulations without a clear process understanding. Results point to the role of the supporting microbial community but it remains to be verified how the complexity of the microbial (inter)actions should be represented in a model framework. (C) 2013 Elsevier B.V. All rights reserved. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000331507700003 |
Publication Date |
2013-11-08 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0169-7722 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
no |
| Call Number |
UA @ admin @ c:irua:115794 |
Serial |
8138 |
| Permanent link to this record |
| |
|
| |
| Author |
Scandura, G.; Eid, S.; Alnajjar, A.A.; Paul, T.; Karanikolos, G.N.; Shetty, D.; Omer, K.; Alqerem, R.; Juma, A.; Wang, H.; Arafat, H.A.; Dumee, L.F. |
| Title |
Photo-responsive metal-organic frameworks – design strategies and emerging applications in photocatalysis and adsorption |
Type |
A1 Journal article |
| Year |
2023 |
Publication |
Materials Advances |
Abbreviated Journal |
|
| Volume |
4 |
Issue |
5 |
Pages |
1258-1285 |
| Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
| Abstract |
Stimuli-responsive metal-organic frameworks (MOFs) are highly versatile porous materials with the ability to respond to different external stimuli, including temperature, pressure, pH, and light. The MOF properties can switch reversibly under specific light irradiation, opening the doors to various applications. This review focuses on design strategies to obtain photo-responsive MOFs, namely (i) encapsulation of photo-switchable molecules as guests in MOF porous structures, (ii) fabrication of MOF composites, (iii) post-synthesis modification, and (iv) synthesis of MOFs with photo-responsive ligands. The most recent reports from the literature are herein reviewed and analyzed in terms of material chemistry and performance. Comparisons between the different strategies are performed and future challenges are discussed. The critical aspect of the fatigue of photo-responsive MOFs applied for prolonged cycling of irradiation is also discussed. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000938241000001 |
Publication Date |
2023-02-24 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ admin @ c:irua:199418 |
Serial |
8913 |
| Permanent link to this record |
| |
|
| |
| Author |
Zhang, J.; Ke, X.; Gou, G.; Seidel, J.; Xiang, B.; Yu, P.; Liang, W.I.; Minor, A.M.; Chu, Y.h.; Van Tendeloo, G.; Ren, X.; Ramesh, R.; |
| Title |
A nanoscale shape memory oxide |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
| Volume |
4 |
Issue |
|
Pages |
2768-8 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| Abstract |
Stimulus-responsive shape-memory materials have attracted tremendous research interests recently, with much effort focused on improving their mechanical actuation. Driven by the needs of nanoelectromechanical devices, materials with large mechanical strain, particularly at nanoscale level, are therefore desired. Here we report on the discovery of a large shape-memory effect in bismuth ferrite at the nanoscale. A maximum strain of up to ~14% and a large volumetric work density of ~600±90 J cm−3 can be achieved in association with a martensitic-like phase transformation. With a single step, control of the phase transformation by thermal activation or electric field has been reversibly achieved without the assistance of external recovery stress. Although aspects such as hysteresis, microcracking and so on have to be taken into consideration for real devices, the large shape-memory effect in this oxide surpasses most alloys and, therefore, demonstrates itself as an extraordinary material for potential use in state-of-art nanosystems. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000328023900006 |
Publication Date |
2013-11-19 |
| 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 |
67 |
Open Access |
|
| Notes |
Countatoms |
Approved |
Most recent IF: 12.124; 2013 IF: 10.742 |
| Call Number |
UA @ lucian @ c:irua:111431 |
Serial |
2271 |
| Permanent link to this record |
| |
|
| |
| Author |
Li, Q.; Niklas, K.J.J.; Niinemets, U.; Zhang, L.; Yu, K.; Gielis, J.; Gao, J.; Shi, P. |
| Title |
Stomatal shape described by a superellipse in four Magnoliaceae species |
Type |
A1 Journal article |
| Year |
2023 |
Publication |
Botany letters |
Abbreviated Journal |
|
| Volume |
|
Issue |
|
Pages |
1-9 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
| Abstract |
Stomata are essential for the exchange of water vapour and atmospheric gases between vascular plants and their external environments. The stomatal geometries of many plants appear to be elliptical. However, prior studies have not tested whether this is a mathematical reality, particularly since many natural shapes that appear to be ellipses are superellipses with greater or smaller edge curvature than predicted for an ellipse. Compared with the ellipse equation, the superellipse equation includes an additional parameter that allows generation of a larger range of shapes. We randomly selected 240 stomata from each of four Magnoliaceae species to test whether the stomatal geometries are superellipses or ellipses. The stomatal geometries for most stomata (943/960) were found to be described better using the superellipse equation. The traditional “elliptical stomata hypothesis” resulted in an underestimation of the area of stomata, whereas the superellipse equation accurately predicted stomatal area. This finding has important implications for the estimation of stomatal area in studies looking at stomatal shape, geometry, and function. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
001024190300001 |
Publication Date |
2023-07-12 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2381-8107; 2381-8115 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
1.5 |
Times cited |
|
Open Access |
Not_Open_Access: Available from 12.01.2024 |
| Notes |
|
Approved |
Most recent IF: 1.5; 2023 IF: NA |
| Call Number |
UA @ admin @ c:irua:197847 |
Serial |
8935 |
| Permanent link to this record |
| |
|
| |
| Author |
da Costa, L.F.; de Barros, A.G.; de Figueiredo Lopes Lucena, L.C.; de Figueiredo Lopes Lucena, A.E. |
| Title |
Asphalt mixture reinforced with banana fibres |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Road Materials And Pavement Design |
Abbreviated Journal |
Road Mater Pavement |
| Volume |
|
Issue |
|
Pages |
|
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT); Energy and Materials in Infrastructure and Buildings (EMIB) |
| Abstract |
Stone Matrix Asphalt (SMA) is a gap-graded mixture which requires high contents of asphalt binder. To prevent draindown, natural or synthetic fibres and polymer-modified asphalt binders are conventionally used in SMA. Banana agribusiness is one of the major sources of post-harvest residue in Brazil. Amongst those residues, fibres extracted from the pseudostem of the banana plant are resistant and used in diverse purposes. The present study assesses the incorporation of fibres from the pseudostem of the banana plant in an SMA mixture. The fibre contents and lengths capable to prevent binder draindown were evaluated from draindown tests. Mechanical properties of an SMA mixture stabilised with different banana fibre lengths were analysed through the tests of Marshall stability, modified Lottman, Indirect Tensile Strength and Cantabro. The results indicated that the fibres studied are a viable alternative for SMA, stabilising draindown and improving its mechanical performance, especially at the length of 20 mm. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000508499900001 |
Publication Date |
2020-01-22 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1468-0629; 2164-7402 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.7 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.7; 2020 IF: 1.401 |
| Call Number |
UA @ admin @ c:irua:178727 |
Serial |
7495 |
| Permanent link to this record |
| |
|
| |
| Author |
Mudronja, D.; Vanmeert, F.; Fazinic, S.; Janssens, K.; Tibljas, D.; Desnica, V. |
| Title |
Protection of stone monuments using a brushing treatment with ammonium oxalate |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Coatings |
Abbreviated Journal |
Coatings |
| Volume |
11 |
Issue |
4 |
Pages |
379 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Stone monuments and buildings are susceptible to weathering. Carbonate-based stones are especially vulnerable in acidic environments, whereas magmatic acidic stones are more susceptible to chemical weathering in basic environments. To slow down surface corrosion of limestone and marble artworks/buildings, protective coatings which inhibit calcite dissolution have been proposed. In this work, samples from two stone types with different porosity were treated with ammonium oxalate (AmOx) to create a protective layer of calcium oxalate (CaOx) using the previously developed brushing method. Two different synchrotron microscopy experiments were performed to determine its protective capability. X-ray powder diffraction (SR-mu-XRPD) in transmission geometry allowed visualization of the distributions of calcium carbonate and oxalates along the sample depths. In a second step, X-ray fluorescence (SR-mu-XRF) was used to check the efficiency/integrity of the protective surface coating layer. This was done by measuring the sulfur distribution on the stone surface after exposing the protected stones to sulfuric acid. XRPD showed the formation of a protective oxalate layer with a thickness of 5-15 mu m on the less porous stone, while a 20-30 mu m thick layer formed on the more porous stone. The XRF study showed that the optimal treatment time depends on the stone porosity. Increasing the treatment time from 1 to 3 h resulted in a decreased efficiency of the protective layer for the low porosity stone. We assume that this is due to the formation of vertical channels (cracks) in the protective layer. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000642940900001 |
Publication Date |
2021-03-25 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2079-6412 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.175 |
Times cited |
|
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 2.175 |
| Call Number |
UA @ admin @ c:irua:178271 |
Serial |
8428 |
| Permanent link to this record |
| |
|
| |
| Author |
Grieb, T.; Krause, F.F.; Schowalter, M.; Zillmann, D.; Sellin, R.; Müller-Caspary, K.; Mahr, C.; Mehrtens, T.; Bimberg, D.; Rosenauer, A. |
| Title |
Strain analysis from nano-beam electron diffraction : influence of specimen tilt and beam convergence |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
| Volume |
190 |
Issue |
190 |
Pages |
45-57 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Strain analyses from experimental series of nano-beam electron diffraction (NBED) patterns in scanning transmission electron microscopy are performed for different specimen tilts. Simulations of NBED series are presented for which strain analysis gives results that are in accordance with experiment. This consequently allows to study the relation between measured strain and actual underlying strain. A two-tilt method which can be seen as lowest-order electron beam precession is suggested and experimentally implemented. Strain determination from NBED series with increasing beam convergence is performed in combination with the experimental realization of a probe-forming aperture with a cross inside. It is shown that using standard evaluation techniques, the influence of beam convergence on spatial resolution is lower than the influence of sharp rings around the diffraction disc which occur at interfaces and which are caused by the tails of the intensity distribution of the electron probe. (C) 2018 Elsevier B.V. All rights reserved. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| Language |
|
Wos |
000432868800006 |
Publication Date |
2018-04-12 |
| 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 |
1 |
Open Access |
OpenAccess |
| Notes |
; This work was supported by the German Research Foundation (DFG) under Contracts RO2057/11-1 and RO2057/12-1. ; |
Approved |
Most recent IF: 2.843 |
| Call Number |
UA @ lucian @ c:irua:151454 |
Serial |
5041 |
| Permanent link to this record |
| |
|
| |
| Author |
Verreck, D.; Verhulst, A.S.; Van de Put, M.L.; Sorée, B.; Collaert, N.; Mocuta, A.; Thean, A.; Groeseneken, G. |
| Title |
Uniform strain in heterostructure tunnel field-effect transistors |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
IEEE electron device letters |
Abbreviated Journal |
Ieee Electr Device L |
| Volume |
37 |
Issue |
37 |
Pages |
337-340 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Strain can strongly impact the performance of III-V tunnel field-effect transistors (TFETs). However, previous studies on homostructure TFETs have found an increase in ON-current to be accompanied with a degradation of subthreshold swing. We perform 30-band quantum mechanical simulations of staggered heterostructure p-n-i-n TFETs submitted to uniaxial and biaxial uniform stress and find the origin of the subthreshold degradation to be a reduction of the density of states in the strained case. We apply an alternative configuration including a lowly doped pocket in the source, which allows to take full benefit of the strain-induced increase in ON-current. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000372372100026 |
Publication Date |
2016-01-27 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0741-3106 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.048 |
Times cited |
17 |
Open Access |
|
| Notes |
; This work was supported by the imec Industrial Affiliation Program. The work of D. Verreck was supported by the Agency for Innovation by Science and Technology in Flanders. The review of this letter was arranged by Editor Z. Chen. ; |
Approved |
Most recent IF: 3.048 |
| Call Number |
UA @ lucian @ c:irua:133207 |
Serial |
4271 |
| Permanent link to this record |
| |
|
| |
| Author |
Prabhakara, V.; Nuytten, T.; Bender, H.; Vandervorst, W.; Bals, S.; Verbeeck, J. |
| Title |
Linearized radially polarized light for improved precision in strain measurements using micro-Raman spectroscopy |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Optics Express |
Abbreviated Journal |
Opt Express |
| Volume |
29 |
Issue |
21 |
Pages |
34531 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Strain engineering in semiconductor transistor devices has become vital in the semiconductor industry due to the ever-increasing need for performance enhancement at the nanoscale. Raman spectroscopy is a non-invasive measurement technique with high sensitivity to mechanical stress that does not require any special sample preparation procedures in comparison to characterization involving transmission electron microscopy (TEM), making it suitable for inline strain measurement in the semiconductor industry. Indeed, at present, strain measurements using Raman spectroscopy are already routinely carried out in semiconductor devices as it is cost effective, fast and non-destructive. In this paper we explore the usage of linearized radially polarized light as an excitation source, which does provide significantly enhanced accuracy and precision as compared to linearly polarized light for this application. Numerical simulations are done to quantitatively evaluate the electric field intensities that contribute to this enhanced sensitivity. We benchmark the experimental results against TEM diffraction-based techniques like nano-beam diffraction and Bessel diffraction. Differences between both approaches are assigned to strain relaxation due to sample thinning required in TEM setups, demonstrating the benefit of Raman for nondestructive inline testing. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000708940500144 |
Publication Date |
2021-10-11 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1094-4087 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.307 |
Times cited |
2 |
Open Access |
OpenAccess |
| Notes |
Horizon 2020 Framework Programme, 823717 – ESTEEM3 ; GOA project, “Solarpaint” ; Herculesstichting;; esteem3jra; esteem3reported; |
Approved |
Most recent IF: 3.307 |
| Call Number |
EMAT @ emat @c:irua:182472 |
Serial |
6816 |
| Permanent link to this record |
| |
|
| |
| Author |
Cooper, D.; Denneulin, T.; Barnes, J.-P.; Hartmann, J.-M.; Hutin, L.; Le Royer, C.; Béché, A.; Rouvière, J.-L. |
| Title |
Strain mapping with nm-scale resolution for the silicon-on-insulator generation of semiconductor devices by advanced electron microscopy |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Applied Physics Letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
112 |
Issue |
|
Pages |
124505 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Strain engineering in the conduction channel is a cost effective method of boosting the performance in state-of-the-art semiconductor devices. However, given the small dimensions of these devices, it is difficult to quantitatively measure the strain with the required spatial resolution. Three different transmission electron microscopy techniques, high-angle annular dark field scanning transmission electron microscopy, dark field electron holography, and nanobeam electron diffraction have been applied to measure the strain in simple bulk and SOI calibration specimens. These techniques are then applied to different gate length SiGe SOI pFET devices in order to measure the strain in the conduction channel. For these devices, improved spatial resolution is required, and strain maps with spatial resolutions as good as 1 nm have been achieved. Finally, we discuss the relative advantages and disadvantages of using these three different techniques when used for strain measurement. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000312829400128 |
Publication Date |
2012-12-19 |
| 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 |
14 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
| Call Number |
UA @ lucian @ c:irua:136433 |
Serial |
4510 |
| Permanent link to this record |
| |
|
| |
| Author |
Aierken, Y.; Çakir, D.; Peeters, F.M. |
| Title |
Strain enhancement of acoustic phonon limited mobility in monolayer TiS3 |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
| Volume |
18 |
Issue |
18 |
Pages |
14434-14441 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Strain engineering is an effective way to tune the intrinsic properties of a material. Here, we show by using first-principles calculations that both uniaxial and biaxial tensile strain applied to monolayer TiS3 are able to significantly modify its intrinsic mobility. From the elastic modulus and the phonon dispersion relation we determine the tensile strain range where structure dynamical stability of the monolayer is guaranteed. Within this region, we find more than one order of enhancement of the acoustic phonon limited mobility at 300 K (100 K), i.e. from 1.71 x 10(4) (5.13 x 10(4)) cm(2) V-1 s(-1) to 5.53 x 10(6) (1.66 x 10(6)) cm(2) V-1 s(-1). The degree of anisotropy in both mobility and effective mass can be tuned by using tensile strain. Furthermore, we can either increase or decrease the band gap of TiS3 monolayer by applying strain along different crystal directions. This property allows us to use TiS3 not only in electronic but also in optical applications. |
| Address |
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| Corporate Author |
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Thesis |
|
| Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
| Language |
|
Wos |
000378102700036 |
Publication Date |
2016-05-05 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1463-9076 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.123 |
Times cited |
24 |
Open Access |
|
| Notes |
; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-V1). Computational resources were provided by HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation and the Flemish Government-department EWI. ; |
Approved |
Most recent IF: 4.123 |
| Call Number |
UA @ lucian @ c:irua:134628 |
Serial |
4250 |
| Permanent link to this record |
| |
|
| |
| Author |
Tirry, W.; Schryvers, D. |
| Title |
3D strain fields surrounding Ni4Ti3: direct measurement and correlation with the R-phase |
Type |
P1 Proceeding |
| Year |
2009 |
Publication |
|
Abbreviated Journal |
|
| Volume |
|
Issue |
|
Pages |
02032,1-02032,6 |
| Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
| Abstract |
Strain fields introduced by coherent Ni4Ti3 precipitates in austenitic Ni-Ti are believed to be a possible origin of why the R-phase transformation is introduced as an extra step before transforming to the B19'. The presence of this strain field was already confirmed in the past by conventional transmission electron microscopy (TEM) techniques and measured quantitatively by high resolution TEM (HRTEM). This time the geometrical phase method is applied on HRTEM micrographs to measure the full 3D strain tensor of the strain fields. Since each atomic resolution micrograph only results in a 2D measurement of the strain, observations in two different zone orientations are combined to retrieve the 3 x 3 strain tensor. In this work observations in a [1-1 1](B2) and [1 0-1](B2) zone orientation are used and this in case of precipitates with a diameter of around 50nm. In a next step the measured strain tensor is compared to the calculated eigenstrain of the R-phase in reference to the B2 matrix. This comparison shows that the introduced strain is very similar to the eigenstrain of one R-phase variant. Since for both structures, Ni4Ti3 and R-phase, four orientation variants are possible, each variant of the R-phase is thus able to accommodate the strain field of one of the Ni4Ti3 variants. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
Edp |
Place of Publication |
Coutaboeuf |
Editor |
|
| Language |
|
Wos |
000274582300036 |
Publication Date |
2009-08-31 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
|
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:81953 |
Serial |
17 |
| Permanent link to this record |
| |
|
| |
| Author |
Guzzinati, G.; Ghielens, W.; Mahr, C.; Béché, A.; Rosenauer, A.; Calders, T.; Verbeeck, J. |
| Title |
Electron Bessel beam diffraction for precise and accurate nanoscale strain mapping |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
114 |
Issue |
24 |
Pages |
243501 |
| Keywords |
A1 Journal article; ADReM Data Lab (ADReM); Electron microscopy for materials research (EMAT) |
| Abstract |
Strain has a strong effect on the properties of materials and the performance of electronic devices. Their ever shrinking size translates into a constant demand for accurate and precise measurement methods with a very high spatial resolution. In this regard, transmission electron microscopes are key instruments thanks to their ability to map strain with a subnanometer resolution. Here, we present a method to measure strain at the nanometer scale based on the diffraction of electron Bessel beams. We demonstrate that our method offers a strain sensitivity better than 2.5 × 10−4 and an accuracy of 1.5 × 10−3, competing with, or outperforming, the best existing methods with a simple and easy to use experimental setup. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000472599100019 |
Publication Date |
2019-06-17 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-6951 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.411 |
Times cited |
17 |
Open Access |
OpenAccess |
| Notes |
Deutsche Forschungsgemeinschaft, RO2057/12-2 ; Fonds Wetenschappelijk Onderzoek, G.0934.17N ; |
Approved |
Most recent IF: 3.411 |
| Call Number |
EMAT @ emat @UA @ admin @ c:irua:160119 |
Serial |
5181 |
| Permanent link to this record |
| |
|
| |
| Author |
Yan, Y.; Zhou, X.; Jin, H.; Li, C.-Z.; Ke, X.; Van Tendeloo, G.; Liu, K.; Yu, D.; Dressel, M.; Liao, Z.-M. |
| Title |
Surface-Facet-Dependent Phonon Deformation Potential in Individual Strained Topological Insulator Bi2Se3 Nanoribbons |
Type |
A1 Journal article |
| Year |
2015 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
| Volume |
9 |
Issue |
9 |
Pages |
10244-10251 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| Abstract |
Strain is an important method to tune the properties of topological insulators. For example, compressive strain can induce superconductivity in Bi2Se3 bulk material. Topological insulator nanostructures are the superior candidates to utilize the unique surface states due to the large surface to volume ratio. Therefore, it is highly desirable to monitor the local strain effects in individual topological insulator nanostructures. Here, we report the systematical micro-Raman spectra of single strained Bi2Se3 nanoribbons with different thicknesses and different surface facets, where four optical modes are resolved in both Stokes and anti-Stokes Raman spectral lines. A striking anisotropy of the strain dependence is observed in the phonon frequency of strained Bi2Se3 nanoribbons grown along the ⟨112̅0⟩ direction. The frequencies of the in-plane Eg2 and out-of-plane A1g1 modes exhibit a nearly linear blue-shift against bending strain when the nanoribbon is bent along the ⟨112̅0⟩ direction with the curved {0001} surface. In this case, the phonon deformation potential of the Eg2 phonon for 100 nm-thick Bi2Se3 nanoribbon is up to 0.94 cm–1/%, which is twice of that in Bi2Se3 bulk material (0.52 cm–1/%). Our results may be valuable for the strain modulation of individual topological insulator nanostructures. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
English |
Wos |
000363915300079 |
Publication Date |
2015-09-12 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
13.942 |
Times cited |
14 |
Open Access |
|
| Notes |
Y.Y. would like to thank Xuewen Fu for helpful discussions. This work was supported by MOST (Nos. 2013CB934600, 2013CB932602) and NSFC (Nos. 11274014, 11234001). |
Approved |
Most recent IF: 13.942; 2015 IF: 12.881 |
| Call Number |
c:irua:129216 |
Serial |
3963 |
| Permanent link to this record |
| |
|
| |
| Author |
Pham, A.-T.; Zhao, Q.-T.; Jungemann, C.; Meinerzhagen, B.; Mantl, S.; Sorée, B.; Pourtois, G. |
| Title |
Comparison of strained SiGe heterostructure-on-insulator (0 0 1) and (1 1 0) PMOSFETs : CV characteristics, mobility, and ON current |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Solid state electronics |
Abbreviated Journal |
Solid State Electron |
| Volume |
65-66 |
Issue |
|
Pages |
64-71 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
Strained SiGe heterostructure-on-insulator (0 0 1) and (1 1 0) PMOSFETs are investigated including important aspects like CV characteristics, mobility, and ON current. The simulations are based on the self-consistent solution of 6 × 6 k · p Schrödinger Equation, multi subband Boltzmann Transport Equation and Poisson Equation, and capture size quantization, strain, crystallographic orientation, and SiGe alloy effects on a solid physical basis. The simulation results are validated by comparison with different experimental data sources. The simulation results show that the strained SiGe HOI PMOSFET with (1 1 0) surface orientation has a higher gate capacitance and a much higher mobility and ON current compared to a similar device with the traditional (0 0 1) surface orientation. |
| Address |
|
| Corporate Author |
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Thesis |
|
| Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| Language |
|
Wos |
000297182700012 |
Publication Date |
2011-07-29 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0038-1101; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.58 |
Times cited |
2 |
Open Access |
|
| Notes |
; ; |
Approved |
Most recent IF: 1.58; 2011 IF: 1.397 |
| Call Number |
UA @ lucian @ c:irua:92866 |
Serial |
433 |
| Permanent link to this record |
| |
|
| |
| Author |
Milovanović, S.P.; Tadic, M.Z.; Peeters, F.M. |
| Title |
Graphene membrane as a pressure gauge |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
111 |
Issue |
4 |
Pages |
043101 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Straining graphene results in the appearance of a pseudo-magnetic field which alters its local electronic properties. Applying a pressure difference between the two sides of the membrane causes it to bend/bulge resulting in a resistance change. We find that the resistance changes linearly with pressure for bubbles of small radius while the response becomes non-linear for bubbles that stretch almost to the edges of the sample. This is explained as due to the strong interference of propagating electronic modes inside the bubble. Our calculations show that high gauge factors can be obtained in this way which makes graphene a good candidate for pressure sensing. Published by AIP Publishing. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000406779700035 |
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 |
11 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Methusalem program, the Erasmus+ programme, and the Serbian Ministry of Education, Science and Technological Development. ; |
Approved |
Most recent IF: 3.411 |
| Call Number |
UA @ lucian @ c:irua:145202 |
Serial |
4718 |
| Permanent link to this record |
| |
|
| |
| Author |
Cai, J.; Griffin, E.; Guarochico-Moreira, V.H.; Barry, D.; Xin, B.; Yagmurcukardes, M.; Zhang, S.; Geim, A.K.; Peeters, F.M.; Lozada-Hidalgo, M. |
| Title |
Wien effect in interfacial water dissociation through proton-permeable graphene electrodes |
Type |
A1 Journal article |
| Year |
2022 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
| Volume |
13 |
Issue |
1 |
Pages |
5776-5777 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
Strong electric fields can accelerate molecular dissociation reactions. The phenomenon known as the Wien effect was previously observed using high-voltage electrolysis cells that produced fields of about 10(7) V m(-1), sufficient to accelerate the dissociation of weakly bound molecules (e.g., organics and weak electrolytes). The observation of the Wien effect for the common case of water dissociation (H2O reversible arrow H+ + OH-) has remained elusive. Here we study the dissociation of interfacial water adjacent to proton-permeable graphene electrodes and observe strong acceleration of the reaction in fields reaching above 10(8) V m(-1). The use of graphene electrodes allows measuring the proton currents arising exclusively from the dissociation of interfacial water, while the electric field driving the reaction is monitored through the carrier density induced in graphene by the same field. The observed exponential increase in proton currents is in quantitative agreement with Onsager's theory. Our results also demonstrate that graphene electrodes can be valuable for the investigation of various interfacial phenomena involving proton transport. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000862552600012 |
Publication Date |
2022-10-01 |
| 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 |
16.6 |
Times cited |
3 |
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 16.6 |
| Call Number |
UA @ admin @ c:irua:191575 |
Serial |
7228 |
| Permanent link to this record |
| |
|
| |
| Author |
Zhang, G.; Turner, S.; Ekimov, E.A.; Vanacken, J.; Timmermans, M.; Samuely, T.; Sidorov, V.A.; Stishov, S.M.; Lu, Y.; Deloof, B.; Goderis, B.; Van Tendeloo, G.; Van de Vondel, J.; Moshchalkov, V.V.; |
| Title |
Global and local superconductivity in boron-doped granular diamond |
Type |
A1 Journal article |
| Year |
2014 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
| Volume |
26 |
Issue |
13 |
Pages |
2034-2040 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| Abstract |
Strong granularity-correlated and intragrain modulations of the superconducting order parameter are demonstrated in heavily boron-doped diamond situated not yet in the vicinity of the metal-insulator transition. These modulations at the superconducting state (SC) and at the global normal state (NS) above the resistive superconducting transition, reveal that local Cooper pairing sets in prior to the global phase coherence. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
| Language |
|
Wos |
000333616700008 |
Publication Date |
2013-12-16 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0935-9648; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
19.791 |
Times cited |
34 |
Open Access |
|
| Notes |
Methusalem Funding; FWO projects; MP1201 COST Action; ERC Grant N246791-COUNTATOMS; post-doctoral grant (S.T.) and for project no. G.0568.10N.;Hercules Foundation |
Approved |
Most recent IF: 19.791; 2014 IF: 17.493 |
| Call Number |
UA @ lucian @ c:irua:116150 |
Serial |
1346 |
| Permanent link to this record |
| |
|
| |
| Author |
Cao, L.-H.; Yu, W.; Xu, H.; Zheng, C.-Y.; Liu, Z.-J.; Li, B.; Bogaerts, A. |
| Title |
Terahertz radiation from oscillating electrons in laser-induced wake fields |
Type |
A1 Journal article |
| Year |
2004 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
| Volume |
70 |
Issue |
|
Pages |
046408,1-7 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
Strong terahertz (1THz=1012Hz) radiation can be generated by the electron oscillation in fs-laser-induced wake fields. The interaction of a fs-laser pulse with a low-density plasma layer is studied in detail using numerical simulations. The spatial distribution and temporal evolution of terahertz electron current developed in a low-density plasma layer are presented, which enables us to calculate the intensity distribution of THz radiation. It is shown that laser and plasma parameters, such as laser intensity, pulse width, and background plasma density, are of key importance to the process. The optimum condition for wake-field excitation and terahertz emission is discussed upon the simulation results. Radiation peaked at 6.4 THz, with 900 fs duration and 9% bandwidth, can be generated in a plasma of density 5×1017cm−3. It turns out that the maximum radiation intensity scales as n03a04 when wake field is resonantly excited, where n0 and a0 are, respectively, the plasma density and the normalized field amplitude of the laser pulse. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
| Language |
|
Wos |
000225689600086 |
Publication Date |
2004-10-14 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.366 |
Times cited |
9 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.366; 2004 IF: NA |
| Call Number |
UA @ lucian @ c:irua:49818 |
Serial |
3509 |
| Permanent link to this record |
| |
|
| |
| Author |
Bekermann, D.; Gasparotto, A.; Barreca, D.; Bovo, L.; Devi, A.; Fischer, R.A.; Lebedev, O.I.; Maccato, C.; Tondello, E.; Van Tendeloo, G. |
| Title |
Highly oriented ZnO nanorod arrays by a novel plasma chemical vapor deposition process |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
| Volume |
10 |
Issue |
4 |
Pages |
2011-2018 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Strongly c-axis oriented ZnO nanorod arrays were grown on Si(100) by plasma enhanced-chemical vapor deposition (PE-CVD) starting from two volatile bis(ketoiminato) zinc(II) compounds Zn[(R′)NC(CH3)═C(H)C(CH3)═O]2, with R′ = -(CH2)xOCH3 (x = 2, 3). A systematic investigation of process parameters enabled us to obtain the selective formation of ZnO nanorods with tailored features, and provided an important insight into their growth mechanism. The morphology, structure, and composition of the synthesized ZnO nanosystems were thoroughly analyzed by field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDXS), glancing incidence X-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Photoluminescence (PL) measurements were carried out to gain information on the optical properties. Specifically, one-dimensional (1D) ZnO architectures could be grown on Si(100) substrates at temperatures as low as 200−300 °C and radio frequency (RF)-power values of 20 W, provided that a sufficiently high mass supply to the growth surface was maintained. To the best of our knowledge, the present work reports the mildest preparation conditions ever appeared in the literature for the PE-CVD of ZnO nanorods, a key result in view of potential large-scale technological applications. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000276234500080 |
Publication Date |
2010-03-18 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1528-7483;1528-7505; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.055 |
Times cited |
75 |
Open Access |
|
| Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.055; 2010 IF: 4.390 |
| Call Number |
UA @ lucian @ c:irua:82311 |
Serial |
1472 |
| Permanent link to this record |
| |
|
| |
| Author |
Cantoro, M.; Klekachev, A.V.; Nourbakhsh, A.; Sorée, B.; Heyns, M.M.; de Gendt, S. |
| Title |
Long-wavelength, confined optical phonons in InAs nanowires probed by Raman spectroscopy |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
| Volume |
79 |
Issue |
4 |
Pages |
423-428 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Strongly confined nano-systems, such as one-dimensional nanowires, feature deviations in their structural, electronic and optical properties from the corresponding bulk. In this work, we investigate the behavior of long-wavelength, optical phonons in vertical arrays of InAs nanowires by Raman spectroscopy. We attribute the main changes in the spectral features to thermal anharmonicity, due to temperature effects, and rule out the contribution of quantum confinement and Fano resonances. We also observe the appearance of surface optical modes, whose details allow for a quantitative, independent estimation of the nanowire diameter. The results shed light onto the mechanisms of lineshape change in low-dimensional InAs nanostructures, and are useful to help tailoring their electronic and vibrational properties for novel functionalities. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Berlin |
Editor |
|
| Language |
|
Wos |
000288120600005 |
Publication Date |
2011-02-03 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1434-6028;1434-6036; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.461 |
Times cited |
10 |
Open Access |
|
| Notes |
; ; |
Approved |
Most recent IF: 1.461; 2011 IF: 1.534 |
| Call Number |
UA @ lucian @ c:irua:89502 |
Serial |
1841 |
| Permanent link to this record |
| |
|
| |
| Author |
Fatermans, J.; Romolini, G.; Altantzis, T.; Hofkens, J.; Roeffaers, M.B.J.; Bals, S.; Van Aert, S. |
| Title |
Atomic-scale detection of individual lead clusters confined in Linde Type A zeolites |
Type |
A1 Journal article |
| Year |
2022 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
| Volume |
|
Issue |
|
Pages |
|
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
| Abstract |
Structural analysis of metal clusters confined in nanoporous materials is typically performed by X-ray-driven techniques. Although X-ray analysis has proved its strength in the characterization of metal clusters, it provides averaged structural information. Therefore, we here present an alternative workflow for bringing the characterization of confined metal clusters towards the local scale. This workflow is based on the combination of aberration-corrected transmission electron microscopy (TEM), TEM image simulations, and powder X-ray diffraction (XRD) with advanced statistical techniques. In this manner, we were able to characterize the clustering of Pb atoms in Linde Type A (LTA) zeolites with Pb loadings as low as 5 wt%. Moreover, individual Pb clusters could be directly detected. The proposed methodology thus enables a local-scale characterization of confined metal clusters in zeolites. This is important for further elucidation of the connection between the structure and the physicochemical properties of such systems. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000809619900001 |
Publication Date |
0000-00-00 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2040-3364 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.7 |
Times cited |
2 |
Open Access |
OpenAccess |
| Notes |
The authors acknowledge the Research Foundation Flanders through project fundings (FWO, G026718N, G050218N, ZW15_09-G0H6316N, and W002221N) and through a PhD scholarship to G.R. (grant 11C6920N), as well as iBOF-21-085 PERSIST. T.A. and S.V.A. acknowledge funding from the University of Antwerp Research fund (BOF). J.H. acknowledges the Flemish government through long-term structural funding Methusalem (CASAS2, Meth/15/04) and the MPI as MPI fellow. M.R. acknowledges funding by the KU Leuven Research Fund (C14/19/079). S.B. and S.V.A. acknowledge funding from the European Research Council under the European Union’s Horizon 2020 research and innovation program (ERC Consolidator Grants No. 815128−REALNANO and No. 770887−PICOMETRICS). The authors thank Dr. D. Chernyshov for the collection of XRD measurements. |
Approved |
Most recent IF: 6.7 |
| Call Number |
EMAT @ emat @c:irua:189061 |
Serial |
7076 |
| Permanent link to this record |
| |
|
| |
| Author |
Santos-Castro, G.; Pandey, T.; Bruno, C.H.V.; Santos Caetano, E.W.; Milošević, M.V.; Chaves, A.; Freire, V.N. |
| Title |
Silicon and germanium adamantane and diamantane monolayers as two-dimensional anisotropic direct-gap semiconductors |
Type |
A1 Journal article |
| Year |
2023 |
Publication |
Physical review B |
Abbreviated Journal |
|
| Volume |
108 |
Issue |
3 |
Pages |
035302-35310 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Structural and electronic properties of silicon and germanium monolayers with two different diamondoid crystal structures are detailed ab initio. Our results show that, despite Si and Ge being well-known indirect gap semiconductors in their bulk form, their adamantane and diamantane monolayers can exhibit optically active direct gap in the visible frequency range, with highly anisotropic effective masses, depending on the monolayer crystal structure. Moreover, we reveal that gaps in these materials are highly tunable with applied strain. These stable monolayer forms of Si and Ge are therefore expected to help bridging the gap between the fast growing area of opto-electronics in two-dimensional materials and the established silicon-based technologies. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
001074455300012 |
Publication Date |
2023-07-05 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
3.7 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.7; 2023 IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:200348 |
Serial |
9089 |
| Permanent link to this record |
| |
|
| |
| Author |
Rezvani, S.J.; Perali, A.; Fretto, M.; De Leo, N.; Flammia, L.; Milošević, M.; Nannarone, S.; Pinto, N. |
| Title |
Substrate-induced proximity effect in superconducting niobium nanofilms |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Condensed Matter |
Abbreviated Journal |
|
| Volume |
4 |
Issue |
1 |
Pages |
4 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Structural and superconducting properties of high-quality niobium nanofilms with different thicknesses are investigated on silicon oxide (SiO2) and sapphire substrates. The role played by the different substrates and the superconducting properties of the Nb films are discussed based on the defectivity of the films and on the presence of an interfacial oxide layer between the Nb film and the substrate. The X-ray absorption spectroscopy is employed to uncover the structure of the interfacial layer. We show that this interfacial layer leads to a strong proximity effect, especially in films deposited on a SiO2 substrate, altering the superconducting properties of the Nb films. Our results establish that the critical temperature is determined by an interplay between quantum-size effects, due to the reduction of the Nb film thicknesses, and proximity effects. The detailed investigation here provides reference characterizations and has direct and important implications for the fabrication of superconducting devices based on Nb nanofilms. |
| Address |
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| Corporate Author |
|
Thesis |
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| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000464289300001 |
Publication Date |
2018-12-31 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2410-3896 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
3 |
Open Access |
|
| Notes |
; This project was financially supported by University of Camerino, FAR project CESEMN. ; |
Approved |
Most recent IF: NA |
| Call Number |
UA @ admin @ c:irua:159463 |
Serial |
5233 |
| Permanent link to this record |
| |
|
| |
| Author |
Verbist, K.; Lebedev, O.I.; Van Tendeloo, G.; Verhoeven, M.A.J.; Rijnders, A.J.H.M.; Blank, D.H.A. |
| Title |
Study of ramp-type Josephson junctions by HREM |
Type |
A1 Journal article |
| Year |
1997 |
Publication |
Electronic Applications; Vol 2: Large Scale And Power Applications |
Abbreviated Journal |
|
| Volume |
|
Issue |
158 |
Pages |
49-52 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Structural aspects of ramp-type Josephson junctions based on REBa2Cu3O7-delta high-T-c superconductors, are investigated by cross-section transmission electron microscopy and results related to fabrication process or physical properties. The barrier layer material is PrBa2Cu3-xGaxO7-delta. The ramp-geometry depends on the etching conditions. High levels of Ga doping (x>0.7) influence the microstructure of the barrier layer thereby changing the junctions properties. |
| 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 |
000071955200012 |
Publication Date |
0000-00-00 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0-7503-0487-1 |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
| Impact Factor |
|
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:102941 |
Serial |
3333 |
| Permanent link to this record |
| |
|
| |
| Author |
Zhao, Q.; Lorenz, H.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Rameshan, C.; Klötzer, B.; Konzett, J.; Penner, S. |
| Title |
Catalytic characterization of pure SnO2 and GeO2 in methanol steam reforming |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Applied catalysis : A : general |
Abbreviated Journal |
Appl Catal A-Gen |
| Volume |
375 |
Issue |
2 |
Pages |
188-195 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Structural changes of a variety of different SnO, SnO2 and GeO2 catalysts upon reduction in hydrogen were correlated with associated catalytic changes in methanol steam reforming. Studied systems include SnO, SnO2 and GeO2 thin film model catalysts prepared by vapour phase deposition and growth on polycrystalline NaCl surfaces and, for comparison, the corresponding pure oxide powder catalysts. Reduction of both the SnO2 thin film and powder at around 673 K in 1 bar hydrogen leads to a substantial reduction of the bulk structure and yields a mixture of SnO2 and metallic β-Sn. On the powder catalyst this transformation is fully reversible upon oxidation in 1 bar O2 at 673 K. Strongly reduced thin films, however, can only be re-transformed to SnO2 if the reduction temperature did not exceed 573 K. For GeO2, the situation is more complex due to its polymorphism. Whereas the tetragonal phase is structurally stable during reduction, oxidation or catalytic reaction, a small part of the hexagonal phase is always transformed into the tetragonal at 673 K independent of the gas phase used. SnO2 is highly active and CO2 selective in methanol steam reforming, but the initial high activity drops considerably upon reduction between 373 and 573 K and almost complete catalyst deactivation is observed after reduction at 673 K, which is associated with the parallel formation of β-Sn. In close correlation to the structural results, the catalytic activity and selectivity can be restored upon an oxidative catalyst regeneration at 673 K. Tetragonal GeO2 exhibits only a small activity and no pronounced selectivity to either CO or CO2, at least after reduction. In its fully oxidized state release of surface/lattice oxygen results in a non-catalytic formation of CO2 by oxidation of CO originating from catalytic dehydrogenation. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| Language |
|
Wos |
000275580600002 |
Publication Date |
2010-01-15 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0926-860X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.339 |
Times cited |
20 |
Open Access |
|
| Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.339; 2010 IF: 3.384 |
| Call Number |
UA @ lucian @ c:irua:81741 |
Serial |
292 |
| Permanent link to this record |
| |
|
| |
| Author |
Neyts, E.C.; Ostrikov, K.; Han, Z.J.; Kumar, S.; van Duin, A.C.T.; Bogaerts, A. |
| Title |
Defect healing and enhanced nucleation of carbon nanotubes by low-energy ion bombardment |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
| Volume |
110 |
Issue |
6 |
Pages |
065501-65505 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
Structural defects inevitably appear during the nucleation event that determines the structure and properties of single-walled carbon nanotubes. By combining ion bombardment experiments with atomistic simulations we reveal that ion bombardment in a suitable energy range allows these defects to be healed resulting in an enhanced nucleation of the carbon nanotube cap. The enhanced growth of the nanotube cap is explained by a nonthermal ion-induced graphene network restructuring mechanism. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000314687300022 |
Publication Date |
2013-02-07 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
8.462 |
Times cited |
50 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 8.462; 2013 IF: 7.728 |
| Call Number |
UA @ lucian @ c:irua:105306 |
Serial |
616 |
| Permanent link to this record |
