Records |
Author |
Leliaert, J.; Dvornik, M.; Mulkers, J.; De Clercq, J.; Milošević, M.V.; Van Waeyenberge, B. |
Title |
Fast micromagnetic simulations on GPU-recent advances made with mumax3 |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
Volume |
51 |
Issue |
12 |
Pages |
123002 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In the last twenty years, numerical modeling has become an indispensable part of magnetism research. It has become a standard tool for both the exploration of new systems and for the interpretation of experimental data. In the last five years, the capabilities of micromagnetic modeling have dramatically increased due to the deployment of graphical processing units (GPU), which have sped up calculations to a factor of 200. This has enabled many studies which were previously unfeasible. In this topical review, we give an overview of this modeling approach and show how it has contributed to the forefront of current magnetism research. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Iop publishing ltd |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000425774100001 |
Publication Date |
2018-01-29 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.588 |
Times cited |
65 |
Open Access |
|
Notes |
; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vlaanderen) through Project No. G098917N. JL is supported by the Ghent University Special Research Fund (BOF postdoctoral fellowship). We gratefully acknowledge the support of the NVIDIA Corporation with the donation of a Titan Xp GPU used for this research. ; |
Approved |
Most recent IF: 2.588 |
Call Number |
UA @ lucian @ c:irua:149852UA @ admin @ c:irua:149852 |
Serial |
4934 |
Permanent link to this record |
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Author |
Scalise, E.; Houssa, M.; Cinquanta, E.; Grazianetti, C.; van den Broek, B.; Pourtois, G.; Stesmans, A.; Fanciulli, M.; Molle, A. |
Title |
Engineering the electronic properties of silicene by tuning the composition of MoX2 and GaX (X = S,Se,Te) chalchogenide templates |
Type |
A1 Journal article |
Year |
2014 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
1 |
Issue |
1 |
Pages |
011010 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
By using first-principles simulations, we investigate the interaction of a 2D silicon layer with two classes of chalcogenide-layered compounds, namely MoX2 and GaX (X = S, Se, Te). A rather weak (van der Waals) interaction between the silicene layers and the chalcogenide layers is predicted. We found that the buckling of the silicene layer is correlated to the lattice mismatch between the silicene layer and the MoX2 or GaX template. The electronic properties of silicene on these different templates largely depend on the buckling of the silicene layer: highly buckled silicene on MoS2 is predicted to be metallic, while low buckled silicene on GaS and GaSe is predicted to be semi-metallic, with preserved Dirac cones at the K points. These results indicate new routes for artificially engineering silicene nanosheets, providing tailored electronic properties of this 2D layer on non-metallic substrates. These non-metallic templates also open the way to the possible integration of silicene in future nanoelectronic devices. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000353649900011 |
Publication Date |
2014-05-29 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
ISSN |
2053-1583; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
49 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 6.937; 2014 IF: NA |
Call Number |
UA @ lucian @ c:irua:126032 |
Serial |
1048 |
Permanent link to this record |
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Author |
Nistor, L.; Bender, H.; van Landuyt, J.; Nemeth, S.; Boeve, H.; De Boeck, J.; Borghs, G. |
Title |
HREM investigation of a Fe/GaN/Fe tunnel junction |
Type |
A1 Journal article |
Year |
2001 |
Publication |
Institute of physics conference series
T2 – Royal-Microscopical-Society Conference on Microscopy of Semiconducting, Materials, MAR 25-29, 2001, Univ of Oxford, Oxford, England |
Abbreviated Journal |
|
Volume |
|
Issue |
169 |
Pages |
53-56 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The structure of Fe/GaN/Fe ferromagnetic electrodes is studied by high resolution transmission electron microscopy. The layers grow epitaxially on the GaAs substrate with the top Fe layer 90degrees rotated compared to the bottom one. The interfaces are quite rough. There is an indication of the possible occurrence of Fe3GaAs formation on the GaAs interface. |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0-7503-0818-4 |
ISBN |
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Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:95715 |
Serial |
1503 |
Permanent link to this record |
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Author |
Fei, G.; Xue-Chun, L.; Zhao, S.-X.; You-Nian, W. |
Title |
Spatial variation behaviors of argon inductively coupled plasma during discharge mode transition |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Chinese physics B |
Abbreviated Journal |
Chinese Phys B |
Volume |
21 |
Issue |
7 |
Pages |
075203 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
A Langmuir probe and an ICCD are employed to study the discharge mode transition in Ar inductively coupled plasma. Electron density and plasma emission intensity are measured during the E (capacitive discharge) to H (inductive discharge) mode transitions at different pressures. It is found that plasma exists with a low electron density and a weak emission intensity in the E mode, while it has a high electron density and a strong emission intensity in the H mode. Meanwhile, the plasma emission intensity spatial (2D image) profile is symmetrical in the H mode, but the 2D image is an asymmetric profile in the E mode. Moreover, the electron density and emission intensity jump up discontinuously at high pressure, but increase almost continuously at the E to H mode transition under low pressure. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
IOP publishing |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000306558300058 |
Publication Date |
2012-07-19 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1674-1056; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.223 |
Times cited |
11 |
Open Access |
|
Notes |
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Approved |
Most recent IF: 1.223; 2012 IF: 1.148 |
Call Number |
UA @ lucian @ c:irua:100843 |
Serial |
3065 |
Permanent link to this record |
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Author |
Ozaydin, H.D.; Sahin, H.; Kang, J.; Peeters, F.M.; Senger, R.T. |
Title |
Electronic and magnetic properties of 1T-TiSe2 nanoribbons |
Type |
A1 Journal article |
Year |
2015 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
2 |
Issue |
2 |
Pages |
044002 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Motivated by the recent synthesis of single layer TiSe2, we used state-of-the-art density functional theory calculations, to investigate the structural and electronic properties of zigzag and armchair-edged nanoribbons (NRs) of this material. Our analysis reveals that, differing from ribbons of other ultra-thin materials such as graphene, TiSe2 NRs have some distinctive properties. The electronic band gap of the NRs decreases exponentially with the width and vanishes for ribbons wider than 20 angstrom. For ultranarrow zigzag-edged NRs we find odd-even oscillations in the band gap width, although their band structures show similar features. Moreover, our detailed magnetic-ground-state analysis reveals that zigzag and armchair edged ribbons have non-magnetic ground states. Passivating the dangling bonds with hydrogen at the edges of the structures influences the band dispersion. Our results shed light on the characteristic properties of T phase NRs of similar crystal structures. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000368936600005 |
Publication Date |
2015-10-13 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2053-1583 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
20 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAK-BIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus Short Marie Curie Fellowship. HDO, HS and RTS acknowledge the support from TUBITAK through project 114F397. ; |
Approved |
Most recent IF: 6.937; 2015 IF: NA |
Call Number |
UA @ lucian @ c:irua:131602 |
Serial |
4169 |
Permanent link to this record |
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Author |
Venturi, F.; Calizzi, M.; Bals, S.; Perkisas, T.; Pasquini, L. |
Title |
Self-assembly of gas-phase synthesized magnesium nanoparticles on room temperature substrates |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Materials research express |
Abbreviated Journal |
Mater Res Express |
Volume |
2 |
Issue |
2 |
Pages |
015007 |
Keywords |
A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT) |
Abstract |
Magnesium nanoparticles (NPs) with initial size in the 10-50 nmrange were synthesized by inert gas condensation under helium flow and deposited on room temperature substrates. The morphology and crystal structure of the NPs ensemble were investigated as a function of the deposition time by complementary electron microscopy techniques, including high resolution imaging and chemical mapping. With increasing amount of material, strong coarsening phenomena were observed at room temperature: small NPs disappeared while large faceted NPs developed, leading to a 5-fold increase of the average NPs size within a few minutes. The extent of coarsening and the final morphology depended also on the nature of the substrate. Furthermore, large single-crystal NPs were seen to arise from the self-organization of primary NPs units, providing a mechanism for crystal growth. The dynamics of the self-assembly process involves the basic steps of NPs sticking, diffusion on substrate, coordinated rotation and attachment/coalescence. Key features are the surface energy anisotropy, reflected by the faceted shape of the NPs, and the low melting point of the material. The observed phenomena have strong implications in relation to the synthesis and stability of nanostructures based on Mg or other elements with similar features. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000369978500007 |
Publication Date |
2014-12-31 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2053-1591 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.068 |
Times cited |
14 |
Open Access |
Not_Open_Access |
Notes |
; Financial support by COST Action MP1103 'Nanostructured Materials for Solid-State Hydrogen Storage' is gratefully acknowledged. ; |
Approved |
Most recent IF: 1.068; 2015 IF: NA |
Call Number |
UA @ lucian @ c:irua:132275 |
Serial |
4240 |
Permanent link to this record |
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Author |
Van der Donck, M.; De Beule, C.; Partoens, B.; Peeters, F.M.; Van Duppen, B. |
Title |
Piezoelectricity in asymmetrically strained bilayer graphene |
Type |
A1 Journal article |
Year |
2016 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
3 |
Issue |
3 |
Pages |
035015 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study the electronic properties of commensurate faulted bilayer graphene by diagonalizing the one-particle Hamiltonian of the bilayer system in a complete basis of Bloch states of the individual graphene layers. Our novel approach is very general and can be easily extended to any commensurate graphene-based heterostructure. Here, we consider three cases: (i) twisted bilayer graphene, (ii) bilayer graphene where triaxial stress is applied to one layer and (iii) bilayer graphene where uniaxial stress is applied to one layer. We show that the resulting superstructures can be divided into distinct classes, depending on the twist angle or the magnitude of the induced strain. The different classes are distinguished from each other by the interlayer coupling mechanism, resulting in fundamentally different low-energy physics. For the cases of triaxial and uniaxial stress, the individual graphene layers tend to decouple and we find significant charge transfer between the layers. In addition, this piezoelectric effect can be tuned by applying a perpendicular electric field. Finally, we show how our approach can be generalized to multilayer systems. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000384072500003 |
Publication Date |
2016-08-31 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
10 |
Open Access |
|
Notes |
; This work was supported by the Research Foundation-Flanders (FWO-Vl) through aspirant research grants to MVDD, CDB, and BVD. ; |
Approved |
Most recent IF: 6.937 |
Call Number |
UA @ lucian @ c:irua:137203 |
Serial |
4361 |
Permanent link to this record |
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Author |
van den Broek, B.; Houssa, M.; Scalise, E.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A. |
Title |
Two-dimensional hexagonal tin : ab initio geometry, stability, electronic structure and functionalization |
Type |
A1 Journal article |
Year |
2014 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
1 |
Issue |
|
Pages |
021004 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We study the structural, mechanical and electronic properties of the two-dimensional (2D) allotrope of tin: tinene/stanene using first-principles calculation within density functional theory, implemented in a set of computer codes. Continuing the trend of the group-IV 2D materials graphene, silicene and germanene; tinene is predicted to have a honeycomb lattice with lattice parameter of a(0) = 4.62 angstrom and a buckling of d(0) = 0.92 angstrom. The electronic dispersion shows a Dirac cone with zero gap at the Fermi energy and a Fermi velocity of v(F) = 0.97 x 10(6) m s(-1); including spin-orbit coupling yields a bandgap of 0.10 eV. The monolayer is thermally stable up to 700 K, as indicated by first-principles molecular dynamics, and has a phonon dispersion without imaginary frequencies. We explore applied electric field and applied strain as functionalization mechanisms. Combining these two mechanisms allows for an induced bandgap up to 0.21 eV, whilst retaining the linear dispersion, albeit with degraded electronic transport parameters. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000353650400004 |
Publication Date |
2014-08-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2053-1583 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
58 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 6.937; 2014 IF: NA |
Call Number |
UA @ lucian @ c:irua:134432 |
Serial |
4530 |
Permanent link to this record |
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Author |
van den Broek, B.; Houssa, M.; Iordanidou, K.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A. |
Title |
Functional silicene and stanene nanoribbons compared to graphene: electronic structure and transport |
Type |
A1 Journal article |
Year |
2016 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
3 |
Issue |
1 |
Pages |
015001 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Since the advent of graphene, other 2D materials have garnered interest; notably the single element materials silicene, germanene, and stanene. Weinvestigate the ballistic current-voltage (I-V) characteristics of armchair silicene and stanene armchair nanoribbons (AXNRs with X = Si, Sn) using a combination of density functional theory and non-equilibrium Green's functions. The impact of out-of-plane electric field and in-plane uniaxial strain on the ribbon geometries, electronic structure, and (I-V)s are considered and contrasted with graphene. Since silicene and stanene are sp(2)/sp(3) buckled layers, the electronic structure can be tuned by an electric field that breaks the sublattice symmetry, an effect absent in graphene. This decreases the current by similar to 50% for Sn, since it has the largest buckling. Uniaxial straining of the ballistic channel affects the AXNR electronic structure in multiple ways: it changes the bandgap and associated effective carrier mass, and creates a local buckling distortion at the lead-channel interface which induces a interface dipole. Due to the increasing sp(3) hybridization character with increasing element mass, large reconstructions rectify the strained systems, an effect absent in sp(2) bonded graphene. This results in a smaller strain effect on the current: a decrease of 20% for Sn at 15% tensile strain compared to a similar to 75% decrease for C. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000373936300021 |
Publication Date |
2016-01-06 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2053-1583 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
19 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 6.937 |
Call Number |
UA @ lucian @ c:irua:144746 |
Serial |
4658 |
Permanent link to this record |
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Author |
Sevik, C.; Wallbank, J.R.; Gulseren, O.; Peeters, F.M.; Çakir, D. |
Title |
Gate induced monolayer behavior in twisted bilayer black phosphorus |
Type |
A1 Journal article |
Year |
2017 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
4 |
Issue |
3 |
Pages |
035025 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Optical and electronic properties of black phosphorus strongly depend on the number of layers and type of stacking. Using first-principles calculations within the framework of density functional theory, we investigate the electronic properties of bilayer black phosphorus with an interlayer twist angle of 90 degrees. These calculations are complemented with a simple (k) over right arrow . (p) over right arrow model which is able to capture most of the low energy features and is valid for arbitrary twist angles. The electronic spectrum of 90 degrees twisted bilayer black phosphorus is found to be x-y isotropic in contrast to the monolayer. However x-y anisotropy, and a partial return to monolayer-like behavior, particularly in the valence band, can be induced by an external out-of-plane electric field. Moreover, the preferred hole effective mass can be rotated by 90 degrees simply by changing the direction of the applied electric field. In particular, a +0.4 (-0.4) V angstrom(1) out-of-plane electric field results in a similar to 60% increase in the hole effective mass along the y (x) axis and enhances the m(y)*/m(x)* (m(x)*/m(y)*) ratio as much as by a factor of 40. Our DFT and (k) over right arrow . (p) over right arrow simulations clearly indicate that the twist angle in combination with an appropriate gate voltage is a novel way to tune the electronic and optical properties of bilayer phosphorus and it gives us a new degree of freedom to engineer the properties of black phosphorus based devices. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000406926600001 |
Publication Date |
2017-08-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2053-1583 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
13 |
Open Access |
|
Notes |
; This work was supported by the bilateral project between the The Scientific and Technological Research Council of Turkey (TUBITAK) and FWO-Flanders, Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TRGrid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. We acknowledge the support from TUBITAK (Grant No. 115F024), ERC Synergy grant Hetero2D and the EU Graphene Flagship Project. We also thank Vladimir Fal'ko for helpful discussions. ; |
Approved |
Most recent IF: 6.937 |
Call Number |
UA @ lucian @ c:irua:145151 |
Serial |
4717 |
Permanent link to this record |
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Author |
Moldovan, D.; Masir, M.R.; Peeters, F.M. |
Title |
Magnetic field dependence of the atomic collapse state in graphene |
Type |
A1 Journal article |
Year |
2018 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
5 |
Issue |
1 |
Pages |
015017 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
<script type='text/javascript'>document.write(unpmarked('Quantum electrodynamics predicts that heavy atoms (Z \u003E Z(c) approximate to 170) will undergo the process of atomic collapse where electrons sink into the positron continuum and a new family of so-called collapsing states emerges. The relativistic electrons in graphene exhibit the same physics but at a much lower critical charge (Z(c) approximate to 1) which has made it possible to confirm this phenomenon experimentally. However, there exist conflicting predictions on the effect of a magnetic field on atomic collapse. These theoretical predictions are based on the continuum Dirac-Weyl equation, which does not have an exact analytical solution for the interplay of a supercritical Coulomb potential and the magnetic field. Approximative solutions have been proposed, but because the two effects compete on similar energy scales, the theoretical treatment varies depending on the regime which is being considered. These limitations are overcome here by starting from a tight-binding approach and computing exact numerical results. By avoiding special limit cases, we found a smooth evolution between the different regimes. We predict that the atomic collapse effect persists even after the magnetic field is activated and that the critical charge remains unchanged. We show that the atomic collapse regime is characterized: (1) by a series of Landau level anticrossings and (2) by the absence of root B scaling of the Landau levels with regard to magnetic field strength.')); |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
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Wos |
000415015000001 |
Publication Date |
2017-10-26 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
13 |
Open Access |
|
Notes |
; We thank Eva Andrei, Jinhai Mao and Yuhang Jiang for insightful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Funding of the Flemish Government. ; |
Approved |
Most recent IF: 6.937 |
Call Number |
UA @ lucian @ c:irua:147361UA @ admin @ c:irua:147361 |
Serial |
4884 |
Permanent link to this record |
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Author |
Peymanirad, F.; Singh, S.K.; Ghorbanfekr-Kalashami, H.; Novoselov, K.S.; Peeters, F.M.; Neek-Amal, M. |
Title |
Thermal activated rotation of graphene flake on graphene |
Type |
A1 Journal article |
Year |
2017 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
4 |
Issue |
2 |
Pages |
025015 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The self rotation of a graphene flake over graphite is controlled by the size, initial misalignment and temperature. Using both ab initio calculations and molecular dynamics simulations, we investigate annealing effects on the self rotation of a graphene flake on a graphene substrate. The energy barriers for rotation and drift of a graphene flake over graphene is found to be smaller than 25 meV/atom which is comparable to thermal energy. We found that small flakes (of about similar to 4 nm) are more sensitive to temperature and initial misorientation angles than larger one (beyond 10 nm). The initial stacking configuration of the flake is found to be important for its dynamics and time evolution of misalignment. Large flakes, which are initially in the AA-or AB-stacking state with small misorientation angle, rotate and end up in the AB-stacking configuration. However small flakes can they stay in an incommensurate state specially when the initial misorientation angle is larger than 2 degrees. Our results are in agreement with recent experiments. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000424399600005 |
Publication Date |
2017-02-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
16 |
Open Access |
|
Notes |
; We would like to acknowledge Annalisa Fasolino and MM van Wijk for providing us with the implemented parameters of REBO-KC [5] in LAMMPS. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation. ; |
Approved |
Most recent IF: 6.937 |
Call Number |
UA @ lucian @ c:irua:149364 |
Serial |
4984 |
Permanent link to this record |
|
|
|
Author |
Hai, G.-Q.; Candido, L.; Brito, B.G.A.; Peeters, F.M. |
Title |
Electron pairing: from metastable electron pair to bipolaron |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Journal of physics communications |
Abbreviated Journal |
|
Volume |
2 |
Issue |
3 |
Pages |
Unsp 035017 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Starting from the shell structure in atoms and the significant correlation within electron pairs, we distinguish the exchange-correlation effects between two electrons of opposite spins occupying the same orbital from the average correlation among many electrons in a crystal. In the periodic potential of the crystal with lattice constant larger than the effective Bohr radius of the valence electrons, these correlated electron pairs can form a metastable energy band above the corresponding single-electron band separated by an energy gap. In order to determine if these metastable electron pairs can be stabilized, we calculate the many-electron exchange-correlation renormalization and the polaron correction to the two-band system with single electrons and electron pairs. We find that the electron-phonon interaction is essential to counterbalance the Coulomb repulsion and to stabilize the electron pairs. The interplay of the electron-electron and electron-phonon interactions, manifested in the exchange-correlation energies, polaron effects, and screening, is responsible for the formation of electron pairs (bipolarons) that are located on the Fermi surface of the single-electron band. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000434996900022 |
Publication Date |
2018-02-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2399-6528 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
9 |
Open Access |
|
Notes |
; This work was supported by the Brazilian agencies FAPESP and CNPq. GQH would like to thank Prof. Bangfen Zhu for his invaluable support and expert advice. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:152079UA @ admin @ c:irua:152079 |
Serial |
5022 |
Permanent link to this record |
|
|
|
Author |
Gul, A.; Bacaksiz, C.; Unsal, E.; Akbali, B.; Tomak, A.; Zareie, H.M.; Sahin, H. |
Title |
Theoretical and experimental investigation of conjugation of 1,6-hexanedithiol on MoS2 |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Materials Research Express |
Abbreviated Journal |
Mater Res Express |
Volume |
5 |
Issue |
3 |
Pages |
036415 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We report an experimental and theoretical investigation of conjugation of 1,6-Hexaneditihiol (HDT) on MoS2 which is prepared by mixing MoS2 structure and HDT molecules in proper solvent. Raman spectra and the calculated phonon bands reveal that the HDT molecules bind covalently to MoS2. Surface morphology of MoS2/HDTstructure is changed upon conjugation ofHDTon MoS2 and characterized by using Scanning Electron Microscope (SEM). Density Functional Theory (DFT) based calculations show that HOMO-LUMO band gap of HDT is altered after the conjugation and two-S binding (handle-like) configuration is energetically most favorable among three different structures. This study displays that the facile thiol functionalization process of MoS2 is promising strategy for obtaining solution processable MoS2. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000428781400003 |
Publication Date |
2018-03-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1591 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.068 |
Times cited |
2 |
Open Access |
|
Notes |
; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). HS acknowledges financial support from the TUBITAK under the project number 116C073. HS acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. ; |
Approved |
Most recent IF: 1.068 |
Call Number |
UA @ lucian @ c:irua:154607UA @ admin @ c:irua:154607 |
Serial |
5133 |
Permanent link to this record |
|
|
|
Author |
Nistor, L.C.; Richard, O.; Zhao, O.; Bender, H.; Stesmans, A.; Van Tendeloo, G. |
Title |
A microstructural study of the thermal stability of atomic layer deposited Al2O3 thin films |
Type |
A1 Journal article |
Year |
2003 |
Publication |
Institute of physics conference series
T2 – Microscopy of semiconducting materials |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
397-400 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The thermal stability of amorphous Al2O3 films (similar to8 and 80 nut thick) deposited by atomic layer deposition on HF-last and thin SiO2 covered (001) Si substrates is studied by transmission electron microscopy. The layers are in- and ex-situ annealed in the same temperature range. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Iop |
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
|
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0-7503-0979-2 |
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:54860 |
Serial |
2048 |
Permanent link to this record |
|
|
|
Author |
Pape, E.; Bezerra, T.N.; Vanneste, H.; Heeschen, K.; Moodley, L.; Leroux, F.; van Breugel, P.; Vanreusel, A. |
Title |
Community structure and feeding preference of nematodes associated with methane seepage at the Darwin mud volcano (Gulf of Cádiz) |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Marine ecology progress series |
Abbreviated Journal |
Mar Ecol Prog Ser |
Volume |
438 |
Issue |
|
Pages |
71-83 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We sampled the Darwin mud volcano (MV) for meiofaunal community and trophic structure in relation to pore-water geochemistry along a 10 m transect from a seep site on the rim of the crater towards the MV slope. Pore-water profiles indicated considerable variation in upward methane (CH4) flow among sediment cores taken along the transect, with highest flux in the seep sediment core, gradually decreasing along the transect, to no CH4 flux in the core taken at a 5 m distance. Low sulphate concentrations and high levels of total alkalinity and sulphide (H2S) suggested that anaerobic oxidation of methane (AOM) occurred close to the sediment surface in the seep sediment core. High H2S levels had a genus- and species-specific impact on meiofaunal densities. Nematode genus composition varied gradually between sediment cores, with the genus Sabatieria dominating almost all sediment cores. However, genus diversity increased with increasing distance from the seep site. These limited data suggest that the community structure of seep meiofauna is highly dependent on local (a)biotic habitat characteristics, and a typical seep meiofaunal community cannot be delineated. Stable isotope values suggested the nematode diet up to 10 m from the seep site included thiotrophic carbon. The thicker hemipelagic sediment layer (photosynthetic carbon), the increased trophic diversity, and the heavier nematode δ13C farther from the seep site suggest a decrease in thiotrophy and an increase in photosynthetic carbon in the nematode diet. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Inter-research |
Place of Publication |
Halstenbek |
Editor |
|
Language |
|
Wos |
000295616000006 |
Publication Date |
2011-07-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0171-8630;1616-1599; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.292 |
Times cited |
18 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.292; 2011 IF: 2.711 |
Call Number |
UA @ lucian @ c:irua:93682 |
Serial |
414 |
Permanent link to this record |
|
|
|
Author |
Pinheiro, C.B.; Abakumov, A.M. |
Title |
Superspace crystallography : a key to the chemistry and properties |
Type |
A1 Journal article |
Year |
2015 |
Publication |
IUCrJ |
Abbreviated Journal |
Iucrj |
Volume |
2 |
Issue |
2 |
Pages |
137-154 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
An overview is given of the recent advances in the field of modulated molecular and inorganic crystals with an emphasis on the links between incommensurability, intermolecular and interatomic interactions and, wherever possible, the properties of the materials. The importance of detailed knowledge on the modulated structure for understanding the crystal chemistry and the functional properties of modulated phases is shown using selected examples of incommensurate modulations in organic molecular compounds and inorganic complex oxides. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Int union crystallography |
Place of Publication |
Chester |
Editor |
|
Language |
|
Wos |
000356865900016 |
Publication Date |
2014-12-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2052-2525; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.793 |
Times cited |
15 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 5.793; 2015 IF: NA |
Call Number |
c:irua:127058 |
Serial |
3382 |
Permanent link to this record |
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|
|
Author |
Saeed, A.; Khan, A.W.; Shafiq, M.; Jan, F.; Abrar, M.; Zaka-ul-Islam, M.; Zakaullah, M. |
Title |
Investigation of 50 Hz pulsed DC nitrogen plasma with active screen cage by trace rare gas optical emission spectroscopy |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Plasma science & technology |
Abbreviated Journal |
Plasma Sci Technol |
Volume |
16 |
Issue |
4 |
Pages |
324-328 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Optical emission spectroscopy is used to investigate the nitrogen-hydrogen with trace rare gas (4% Ar) plasma generated by 50 Hz pulsed DC discharges. The filling pressure varies from 1 mbar to 5 mbar and the current density ranges from 1 mA.cm(-2) to 4 mA.cm(-2). The hydrogen concentration in the mixture plasma varies from 0% to 80%, with the objective of identifying the optimum pressure, current density and hydrogen concentration for active species ([N] and [N-2]) generation. It is observed that in an N-2-H-2 gas mixture, the concentration of N atom density decreases with filling pressure and increases with current density, with other parameters of the discharge kept unchanged. The maximum concentrations of active species were found for 40% H-2 in the mixture at 3 mbar pressure and current density of 4 mA.cm(-2). |
Address |
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Corporate Author |
|
Thesis |
|
Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Institute of Plasma Physics, the Chinese Academy of Sciences |
Place of Publication |
Beijing |
Editor |
|
Language |
|
Wos |
000335909600005 |
Publication Date |
2014-04-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1009-0630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.83 |
Times cited |
5 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 0.83; 2014 IF: 0.579 |
Call Number |
UA @ lucian @ c:irua:117686 |
Serial |
1728 |
Permanent link to this record |
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|
|
Author |
Kolev, S.; Bogaerts, A. |
Title |
A 2D model for a gliding arc discharge |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
24 |
Issue |
24 |
Pages |
015025 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this study we report on a 2D fluid model of a gliding arc discharge in argon. Despite the 3D nature of the discharge, 2D models are found to be capable of providing very useful information about the operation of the discharge. We employ two modelsan axisymmetric and a Cartesian one. We show that for the considered experiment and the conditions of a low current arc (around 30 mA) in argon, there is no significant heating of the cathode surface and the discharge is sustained by field electron emission from the cathode accompanied by the formation of a cathode spot. The obtained discharge power and voltage are relatively sensitive to the surface properties and particularly to the surface roughness, causing effectively an amplification of the normal electric field. The arc body and anode region are not influenced by this and depend mainly on the current value. The gliding of the arc is modelled by means of a 2D Cartesian model. The arcelectrode contact points are analysed and the gliding mechanism along the electrode surface is discussed. Following experimental observations, the cathode spot is simulated as jumping from one point to another. A complete arc cycle is modelled from initial ignition to arc decay. The results show that there is no interaction between the successive gliding arcs. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000348298200026 |
Publication Date |
2014-12-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
34 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.302; 2015 IF: 3.591 |
Call Number |
c:irua:122538 c:irua:122538 c:irua:122538 c:irua:122538 |
Serial |
3 |
Permanent link to this record |
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|
|
Author |
Bultinck, E.; Bogaerts, A. |
Title |
Characterization of an Ar/O2 magnetron plasma by a multi-species Monte Carlo model |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
20 |
Issue |
4 |
Pages |
045013-045013,12 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
A combined Monte Carlo (MC)/analytical surface model is developed to study the plasma processes occurring during the reactive sputter deposition of TiOx thin films. This model describes the important plasma species with a MC approach (i.e. electrons, Ar+ ions, {\rm O}_2 |
Address |
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Corporate Author |
|
Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000295829800015 |
Publication Date |
2011-06-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
7 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.302; 2011 IF: 2.521 |
Call Number |
UA @ lucian @ c:irua:89732 |
Serial |
316 |
Permanent link to this record |
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|
|
Author |
Bogaerts, A. |
Title |
Comprehensive modelling network for dc glow discharges in argon |
Type |
A1 Journal article |
Year |
1999 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
8 |
Issue |
|
Pages |
210-229 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000080660600004 |
Publication Date |
2002-08-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
27 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.302; 1999 IF: 2.038 |
Call Number |
UA @ lucian @ c:irua:24129 |
Serial |
451 |
Permanent link to this record |
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|
|
Author |
Tinck, S.; Bogaerts, A. |
Title |
Computer simulations of an oxygen inductively coupled plasma used for plasma-assisted atomic layer deposition |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
20 |
Issue |
1 |
Pages |
015008-015008,10 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this paper, an O2 inductively coupled plasma used for plasma enhanced atomic layer deposition of Al2O3 thin films is investigated by means of modeling. This work intends to provide more information about basic plasma properties such as species densities and species fluxes to the substrate as a function of power and pressure, which might be hard to measure experimentally. For this purpose, a hybrid model developed by Kushner et al is applied to calculate the plasma characteristics in the reactor volume for different chamber pressures ranging from 1 to 10 mTorr and different coil powers ranging from 50 to 500 W. Density profiles of the various oxygen containing plasma species are reported as well as fluxes to the substrate under various operating conditions. Furthermore, different orientations of the substrate, which can be placed vertically or horizontally in the reactor, are taken into account. In addition, special attention is paid to the recombination process of atomic oxygen on the different reactor walls under the stated operating conditions. From this work it can be concluded that the plasma properties change significantly in different locations of the reactor. The plasma density near the cylindrical coil is high, while it is almost negligible in the neighborhood of the substrate. Ion and excited species fluxes to the substrate are found to be very low and negligible. Finally, the orientation of the substrate has a minor effect on the flux of O2, while it has a significant effect on the flux of O. In the horizontal configuration, the flux of atomic oxygen can be up to one order of magnitude lower than in the vertical configuration. |
Address |
|
Corporate Author |
|
Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000286592200009 |
Publication Date |
2011-01-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.302; 2011 IF: 2.521 |
Call Number |
UA @ lucian @ c:irua:85285 |
Serial |
467 |
Permanent link to this record |
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|
|
Author |
Paulussen, S.; Verheyde, B.; Tu, X.; De Bie, C.; Martens, T.; Petrovic, D.; Bogaerts, A.; Sels, B. |
Title |
Conversion of carbon dioxide to value-added chemicals in atmospheric pressure dielectric barrier discharges |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
19 |
Issue |
3 |
Pages |
034015,1-034015,6 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The aim of this work consists of the evaluation of atmospheric pressure dielectric barrier discharges for the conversion of greenhouse gases into useful compounds. Therefore, pure CO2 feed flows are administered to the discharge zone at varying discharge frequency, power input, gas temperature and feed flow rates, aiming at the formation of CO and O2. The discharge obtained in CO2 is characterized as a filamentary mode with a microdischarge zone in each half cycle of the applied voltage. It is shown that the most important parameter affecting the CO2-conversion levels is the gas flow rate. At low flow rates, both the conversion and the CO-yield are significantly higher. In addition, also an increase in the gas temperature and the power input give rise to higher conversion levels, although the effect on the CO-yield is limited. The optimum discharge frequency depends on the power input level and it cannot be unambiguously stated that higher frequencies give rise to increased conversion levels. A maximum CO2 conversion of 30% is achieved at a flow rate of 0.05 L min−1, a power density of 14.75 W cm−3 and a frequency of 60 kHz. The most energy efficient conversions are achieved at a flow rate of 0.2 L min−1, a power density of 11 W cm−3 and a discharge frequency of 30 kHz. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000277982800016 |
Publication Date |
2010-05-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
116 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.302; 2010 IF: 2.218 |
Call Number |
UA @ lucian @ c:irua:82408 |
Serial |
512 |
Permanent link to this record |
|
|
|
Author |
De Bie, C.; Martens, T.; van Dijk, J.; Paulussen, S.; Verheyde, B.; Corthals, S.; Bogaerts, A. |
Title |
Dielectric barrier discharges used for the conversion of greenhouse gases: modeling the plasma chemistry by fluid simulations |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
20 |
Issue |
2 |
Pages |
024008,1-024008,11 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The conversion of methane to value-added chemicals and fuels is considered to be one of the challenges of the 21st century. In this paper we study, by means of fluid modeling, the conversion of methane to higher hydrocarbons or oxygenates by partial oxidation with CO2 or O2 in a dielectric barrier discharge. Sixty-nine different plasma species (electrons, ions, molecules, radicals) are included in the model, as well as a comprehensive set of chemical reactions. The calculation results presented in this paper include the conversion of the reactants and the yields of the reaction products as a function of residence time in the reactor, for different gas mixing ratios. Syngas (i.e. H2 + CO) and higher hydrocarbons (C2Hx) are typically found to be important reaction products. |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000290719900009 |
Publication Date |
2011-04-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252;1361-6595; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
38 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.302; 2011 IF: 2.521 |
Call Number |
UA @ lucian @ c:irua:87868 |
Serial |
689 |
Permanent link to this record |
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Author |
Peerenboom, K.; Parente, A.; Kozák, T.; Bogaerts, A.; Degrez, G. |
Title |
Dimension reduction of non-equilibrium plasma kinetic models using principal component analysis |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
24 |
Issue |
24 |
Pages |
025004 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The chemical complexity of non-equilibrium plasmas poses a challenge for plasma modeling because of the computational load. This paper presents a dimension reduction method for such chemically complex plasmas based on principal component analysis (PCA). PCA is used to identify a low-dimensional manifold in chemical state space that is described by a small number of parameters: the principal components. Reduction is obtained since continuity equations only need to be solved for these principal components and not for all the species. Application of the presented method to a CO2 plasma model including state-to-state vibrational kinetics of CO2 and CO demonstrates the potential of the PCA method for dimension reduction. A manifold described by only two principal components is able to predict the CO2 to CO conversion at varying ionization degrees very accurately. |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000356816200008 |
Publication Date |
2015-01-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252;1361-6595; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
11 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.302; 2015 IF: 3.591 |
Call Number |
c:irua:123534 |
Serial |
704 |
Permanent link to this record |
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Author |
Zhao, S.-X.; Gao, F.; Wang, Y.-N.; Bogaerts, A. |
Title |
The effect of F2 attachment by low-energy electrons on the electron behaviour in an Ar/CF4 inductively coupled plasma |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
21 |
Issue |
2 |
Pages |
025008-025008,13 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The electron behaviour in an Ar/CF4 inductively coupled plasma is investigated by a Langmuir probe and a hybrid model. The simulated and measured results include electron density, temperature and electron energy distribution function for different values of Ar/CF4 ratio, coil power and gas pressure. The hybrid plasma equipment model simulations show qualitative agreement with experiment. The effect of F2 electron attachment on the electron behaviour is explored by comparing two sets of data based on different F atom boundary conditions. It is demonstrated that electron attachment at F2 molecules is responsible for the depletion of low-energy electrons, causing a density decrease as well as a temperature increase when CF4 is added to an Ar plasma. |
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Corporate Author |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000302779400022 |
Publication Date |
2012-03-12 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252;1361-6595; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
23 |
Open Access |
|
Notes |
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Approved |
Most recent IF: 3.302; 2012 IF: 2.515 |
Call Number |
UA @ lucian @ c:irua:96549 |
Serial |
841 |
Permanent link to this record |
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Author |
Liu, Y.-X.; Zhang, Q.-Z.; Liu, L.; Song, Y.-H.; Bogaerts, A.; Wang, Y.-N. |
Title |
Electron bounce resonance heating in dual-frequency capacitively coupled oxygen discharges |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
22 |
Issue |
2 |
Pages |
025012-11 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The electron bounce resonance heating (BRH) in dual-frequency capacitively coupled plasmas operated in oxygen is studied by different experimental methods and a particle-in-cell/Monte Carlo collision (PIC/MCC) simulation, and compared with the electropositive argon discharge. In comparison with argon, the experimental results show that in an oxygen discharge the resonance peaks in positive-ion density and light intensity tend to occur at larger electrode gaps. Moreover, at electrode gaps L > 2.5 cm, the positive-ion (and electron) density and the light emission drop monotonically in the oxygen discharge upon increasing L, whereas they rise (after an initial drop) in the argon case. At resonance gap the electronegativity reaches its maximum due to the BRH. All these experimental observations are explained by PIC/MCC simulations, which show that in the oxygen discharge the bulk electric field becomes quite strong and is out of phase with the sheath field. Therefore, it retards the resonance electrons when traversing the bulk, resulting in a suppressed BRH. Both experiment and simulation results show that this effect becomes more pronounced at lower high-frequency power, when the discharge mode changes from electropositive to electronegative. In a pure oxygen discharge, the BRH is suppressed with increasing pressure and almost diminishes at 12 Pa. Finally, the driving frequency significantly affects the BRH, because it determines the phase relation between bulk electric field and sheath electric field. |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000317275400014 |
Publication Date |
2013-03-18 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252;1361-6595; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
20 |
Open Access |
|
Notes |
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Approved |
Most recent IF: 3.302; 2013 IF: 3.056 |
Call Number |
UA @ lucian @ c:irua:106534 |
Serial |
911 |
Permanent link to this record |
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Author |
Yan, M.; Bogaerts, A.; Goedheer, W.J.; Gijbels, R. |
Title |
Electron energy distribution function in capacitively coupled RF discharges: differences between electropositive Ar and electronegative SiH4 discharges |
Type |
A1 Journal article |
Year |
2000 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
9 |
Issue |
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Pages |
583-591 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000165341000015 |
Publication Date |
2002-08-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252;1361-6595; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
21 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.302; 2000 IF: 1.963 |
Call Number |
UA @ lucian @ c:irua:34071 |
Serial |
929 |
Permanent link to this record |
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Author |
Van Laer, K.; Tinck, S.; Samara, V.; de Marneffe, J.F.; Bogaerts, A. |
Title |
Etching of low-k materials for microelectronics applications by means of a N2/H2 plasma : modeling and experimental investigation |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
22 |
Issue |
2 |
Pages |
025011-25019 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this paper, we investigate the etch process of so-called low-k organic material by means of a N2/H2 capacitively coupled plasma, as applied in the micro-electronics industry for the manufacturing of computer chips. In recent years, such an organic material has emerged as a possible alternative for replacing bulk SiO2 as a dielectric material in the back-end-of-line, because of the smaller parasitic capacity between adjacent conducting lines, and thus a faster propagation of the electrical signals throughout the chip. Numerical simulations with a hybrid plasma model, using an extensive plasma and surface chemistry set, as well as experiments are performed, focusing on the plasma properties as well as the actual etching process, to obtain a better insight into the underlying mechanisms. Furthermore, the effects of gas pressure, applied power and gas composition are investigated to try to optimize the etch process. In general, the plasma density reaches a maximum near the wafer edge due to the so-called 'edge effect'. As a result, the etch rate is not uniform but will also reach its maximum near the wafer edge. The pressure seems not to have a big effect. A higher power increases the etch rate, but the uniformity becomes (slightly) worse. The gas mixing ratio has no significant effect on the etch process, except when a pure H2 or N2 plasma is used, illustrating the synergistic effects of a N2/H2 plasma. In fact, our calculations reveal that the N2/H2 plasma entails an ion-enhanced etch process. The simulation results are in reasonable agreement with the experimental values. The microscopic etch profile shows the desired anisotropic shape under all conditions under study. |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000317275400013 |
Publication Date |
2013-03-18 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252;1361-6595; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
13 |
Open Access |
|
Notes |
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Approved |
Most recent IF: 3.302; 2013 IF: 3.056 |
Call Number |
UA @ lucian @ c:irua:106654 |
Serial |
1084 |
Permanent link to this record |
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Author |
Kozák, T.; Bogaerts, A. |
Title |
Evaluation of the energy efficiency of CO2 conversion in microwave discharges using a reaction kinetics model |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
24 |
Issue |
24 |
Pages |
015024 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We use a zero-dimensional reaction kinetics model to simulate CO2 conversion in microwave discharges where the excitation of the vibrational levels plays a significant role in the dissociation kinetics. The model includes a description of the CO2 vibrational kinetics, taking into account state-specific VT and VV relaxation reactions and the effect of vibrational excitation on other chemical reactions. The model is used to simulate a general tubular microwave reactor, where a stream of CO2 flows through a plasma column generated by microwave radiation. We study the effects of the internal plasma parameters, namely the reduced electric field, electron density and the total specific energy input, on the CO2 conversion and its energy efficiency. We report the highest energy efficiency (up to 30%) for a specific energy input in the range 0.41.0 eV/molecule and a reduced electric field in the range 50100 Td and for high values of the electron density (an ionization degree greater than 10−5). The energy efficiency is mainly limited by the VT relaxation which contributes dominantly to the vibrational energy losses and also contributes significantly to the heating of the reacting gas. The model analysis provides useful insight into the potential and limitations of CO2 conversion in microwave discharges. |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000348298200025 |
Publication Date |
2014-12-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252;1361-6595; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
100 |
Open Access |
|
Notes |
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Approved |
Most recent IF: 3.302; 2015 IF: 3.591 |
Call Number |
c:irua:122243 |
Serial |
1087 |
Permanent link to this record |