| Records |
| Author |
Van Duppen, B.; Peeters, F.M. |
| Title |
Klein paradox for a pn junction in multilayer graphene |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Europhysics letters |
Abbreviated Journal |
Epl-Europhys Lett |
| Volume |
102 |
Issue |
2 |
Pages |
27001-27005 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Charge carriers in single and multilayered graphene systems behave as chiral particles due to the particular lattice symmetry of the crystal. We show that the interplay between the meta-material properties of graphene multilayers and the pseudospinorial properties of the charge carriers result in the occurrence of Klein and anti-Klein tunneling for rhombohedral stacked multilayers. We derive an algebraic formula predicting the angles at which these phenomena occur and support this with numerical calculations for systems up to four layers. We present a decomposition of an arbitrarily stacked multilayer into pseudospin doublets that have the same properties as rhombohedral systems with a lower number of layers. Copyright (C) EPLA, 2013 |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Paris |
Editor |
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| Language |
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Wos |
000319617700017 |
Publication Date |
2013-05-02 |
| Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0295-5075;1286-4854; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.957 |
Times cited |
17 |
Open Access |
|
| Notes |
; We thank S. GILLIS for valuable discussions. This work was supported by the European Science Foundation (ESF) under the EUROCORES Program Euro-GRAPHENE within the project CONGRAN, the Flemish Science Foundation (FWO-Vl) by an aspirant research grant to B. Van Duppen and the Methusalem Programme of the Flemish Government. ; |
Approved |
Most recent IF: 1.957; 2013 IF: 2.269 |
Call Number  |
UA @ lucian @ c:irua:109665 |
Serial |
1763 |
| Permanent link to this record |
| |
|
| |
| Author |
Pogosov, W.V.; Lin, N.; Misko, V.R. |
| Title |
Electron-hole symmetry and solutions of Richardson pairing model |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
| Volume |
86 |
Issue |
5 |
Pages |
235-236 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Richardson approach provides an exact solution of the pairing Hamiltonian. This Hamiltonian is characterized by the electron-hole pairing symmetry, which is however hidden in Richardson equations. By analyzing this symmetry and using an additional conjecture, fulfilled in solvable limits, we suggest a simple expression of the ground state energy for an equally-spaced energy-level model, which is applicable along the whole crossover from the superconducting state to the pairing fluctuation regime. Solving Richardson equations numerically, we demonstrate a good accuracy of our expression. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
Berlin |
Editor |
|
| Language |
|
Wos |
000320286200044 |
Publication Date |
2013-05-28 |
| 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 |
6 |
Open Access |
|
| Notes |
; This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl). W.V.P. acknowledges useful discussions with Monique Combescot and the support from the Dynasty Foundation, the RFBR (project No. 12-02-00339), and RFBR-CNRS programme (project No. 12-02-91055). ; |
Approved |
Most recent IF: 1.461; 2013 IF: 1.463 |
| Call Number |
UA @ lucian @ c:irua:109657 |
Serial |
935 |
| Permanent link to this record |
| |
|
| |
| Author |
Carrillo-Nuñez, H.; Magnus, W.; Vandenberghe, W.G.; Sorée, B.; Peeters, F.M. |
| Title |
Phonon-assisted Zener tunneling in a cylindrical nanowire transistor |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| Volume |
113 |
Issue |
18 |
Pages |
184507-184508 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The tunneling current has been computed for a cylindrical nanowire tunneling field-effect transistor (TFET) with an all-round gate that covers the source region. Being the underlying mechanism, band-to-band tunneling, mediated by electron-phonon interaction, is pronouncedly affected by carrier confinement in the radial direction and, therefore, involves the self-consistent solution of the Schrodinger and Poisson equations. The latter has been accomplished by exploiting a non-linear variational principle within the framework of the modified local density approximation taking into account the nonparabolicity of both the valence band and conduction band in relatively thick wires. Moreover, while the effective-mass approximation might still provide a reasonable description of the conduction band in relatively thick wires, we have found that the nonparabolicity of the valence band needs to be included. As a major conclusion, it is observed that confinement effects in nanowire tunneling field-effect transistors have a stronger impact on the onset voltage of the tunneling current in comparison with planar TFETs. On the other hand, the value of the onset voltage is found to be overestimated when the valence band nonparabolicity is ignored. (C) 2013 AIP Publishing LLC. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000319294100093 |
Publication Date |
2013-05-10 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.068 |
Times cited |
4 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI), and the Interuniversity Attraction Poles, Belgium State, Belgium Science Policy, and IMEC. ; |
Approved |
Most recent IF: 2.068; 2013 IF: 2.185 |
| Call Number |
UA @ lucian @ c:irua:109651 |
Serial |
2599 |
| Permanent link to this record |
| |
|
| |
| Author |
Berdiyorov, G.R.; Doria, M.M.; de Romaguera, A.R.C.; Milošević, M.V.; Brandt, E.H.; Peeters, F.M. |
| Title |
Current-induced cutting and recombination of magnetic superconducting vortex loops in mesoscopic superconductor-ferromagnet heterostructures |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
87 |
Issue |
18 |
Pages |
184508-5 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Vortex loops are generated by the inhomogeneous stray field of a magnetic dipole on top of a current-carrying mesoscopic superconductor. Cutting and recombination processes unfold under the applied drive, resulting in periodic voltage oscillations across the sample. We show that a direct and detectable consequence of the cutting and recombination of these vortex loops in the present setup is the onset of vortices at surfaces where they were absent prior to the application of the external current. The nonlinear dynamics of vortex loops is studied within the time-dependent Ginzburg-Landau theory to describe the profound three-dimensional features of their time evolution. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Wos |
000319252000008 |
Publication Date |
2013-05-21 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
13 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI) and the bilateral programme between Flanders and Brazil. G.R.B. acknowledges support from FWO-VI. A.R. de C.R. acknowledges CNPq for financial support. ; |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
| Call Number |
UA @ lucian @ c:irua:109648 |
Serial |
593 |
| Permanent link to this record |
| |
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| |
| Author |
Berdiyorov, G.R.; Savel'ev, S.E.; Milošević, M.V.; Kusmartsev, F.V.; Peeters, F.M. |
| Title |
Synchronized dynamics of Josephson vortices in artificial stacks of SNS Josephson junctions under both dc and ac bias currents |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
87 |
Issue |
18 |
Pages |
184510-184519 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Nonlinear dynamics of Josephson vortices (fluxons) in artificial stacks of superconducting-normal-superconducting Josephson junctions under simultaneously applied time-periodic ac and constant biasing dc currents is studied using the time dependent Ginzburg-Landau formalism with a Lawrence-Doniach extension. At zero external magnetic field and dc biasing current the resistive state of the system is characterized by periodic nucleation and annihilation of fluxon-antifluxon pairs, relative positions of which are determined by the state of neighboring junctions. Due to the mutual repulsive interaction, fluxons in different junctions move out of phase. Their collective motion can be synchronized by adding a small ac component to the biasing dc current. Coherent motion of fluxons is observed for a broad frequency range of the applied drive. In the coherent state the maximal output voltage, which is proportional to the number of junctions in the stack, is observed near the characteristic frequency of the system determined by the crossing of the fluxons across the sample. However, in this frequency range the dynamically synchronized state has an alternative-a less ordered state with smaller amplitude of the output voltage. Collective behavior of the junctions is strongly affected by the sloped sidewalls of the stack. Synchronization is observed only for weakly trapezoidal cross sections, whereas irregular motion of fluxons is observed for larger slopes of the sample edge. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000319653400007 |
Publication Date |
2013-05-28 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
10 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI) and by EU Marie Curie (Project No. 253057). ; |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
| Call Number |
UA @ lucian @ c:irua:109643 |
Serial |
3406 |
| Permanent link to this record |
| |
|
| |
| Author |
Van Hoorebeke, L.; Leroux, O.; Leroux, F.; Mastroberti, A.A.; Santos-Silva, F.; Van Loo, D.; Bagniewska-Zadworna, A.; Bals, S.; Popper, Z.A.; de Araujo Mariath, J.E. |
| Title |
Heterogeneity of silica and glycan-epitope distribution in epidermal idioblast cell walls in Adiantum raddianum laminae |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Planta |
Abbreviated Journal |
Planta |
| Volume |
237 |
Issue |
6 |
Pages |
1453-1464 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Laminae of Adiantum raddianum Presl., a fern belonging to the family Pteridaceae, are characterised by the presence of epidermal fibre-like cells under the vascular bundles. These cells were thought to contain silica bodies, but their thickened walls leave no space for intracellular silica suggesting it may actually be deposited within their walls. Using advanced electron microscopy in conjunction with energy dispersive X-ray microanalysis we showed the presence of silica in the cell walls of the fibre-like idioblasts. However, it was specifically localised to the outer layers of the periclinal wall facing the leaf surface, with the thick secondary wall being devoid of silica. Immunocytochemical experiments were performed to ascertain the respective localisation of silica deposition and glycan polymers. Epitopes characteristic for pectic homogalacturonan and the hemicelluloses xyloglucan and mannan were detected in most epidermal walls, including the silica-rich cell wall layers. The monoclonal antibody, LM6, raised against pectic arabinan, labelled the silica-rich primary wall of the epidermal fibre-like cells and the guard cell walls, which were also shown to contain silica. We hypothesise that the silicified outer wall layers of the epidermal fibre-like cells support the lamina during cell expansion prior to secondary wall formation. This implies that silicification does not impede cell elongation. Although our results suggest that pectic arabinan may be implicated in silica deposition, further detailed analyses are needed to confirm this. The combinatorial approach presented here, which allows correlative screening and in situ localisation of silicon and cell wall polysaccharide distribution, shows great potential for future studies. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000319474200004 |
Publication Date |
2013-02-21 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0032-0935;1432-2048; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.361 |
Times cited |
16 |
Open Access |
|
| Notes |
We are grateful to the Laboratorio de Anatomia Vegetal of Universidade Federal do Rio Grande do Sul (UFRGS) and the Centro de Microscopia Eletronica (CME) of UFRGS. Thanks to Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) for the undergraduate degree grant provided (PIBIC) for the fourth author and research grant and support for the last one. The third author is grateful to Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) for providing financial support (PRODOC). We acknowledge Christiane de Queiroz Lopes and Moema Queiroz (CME) for the technical assistance. We are indebted to Paul Knox (Centre for Plant Sciences, University of Leeds, UK) for kindly providing the monoclonal antibodies used in this study. The Fund for Scientific Research-Flanders (FWO) is acknowledged for the doctoral grant to D. Van Loo (G.0100.08). |
Approved |
Most recent IF: 3.361; 2013 IF: 3.376 |
| Call Number |
UA @ lucian @ c:irua:109641 |
Serial |
1419 |
| Permanent link to this record |
| |
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| |
| Author |
Masir, M.R.; Peeters, F.M. |
| Title |
Scattering of Dirac electrons by a random array of magnetic flux tubes |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Journal of computational electronics |
Abbreviated Journal |
J Comput Electron |
| Volume |
12 |
Issue |
2 |
Pages |
115-122 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The scattering of two-dimensional (2D) massless electrons as presented in graphene in the presence of a random array of circular magnetic flux tubes is investigated. The momentum relaxation time and the Hall factor are obtained using optical theorem techniques for scattering. Electrons with energy close to those of the Landau levels of the flux tubes exhibit resonant scattering and have a long life-time to reside inside the magnetic flux tube. These resonances appear as sharp structures in the Hall factor and the magneto-resistance. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
S.l. |
Editor |
|
| Language |
|
Wos |
000320044900007 |
Publication Date |
2013-02-15 |
| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1569-8025;1572-8137; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.526 |
Times cited |
2 |
Open Access |
|
| Notes |
; This work was supported by the European Science Foundation (ESF) under the EUROCORES Program Euro-GRAPHENE within the project CONGRAN and the Flemish Science Foundation (FWO-Vl). We acknowledge fruitful discussions with A. Matulis. ; |
Approved |
Most recent IF: 1.526; 2013 IF: 1.372 |
| Call Number |
UA @ lucian @ c:irua:109615 |
Serial |
2950 |
| Permanent link to this record |
| |
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| |
| Author |
Zhao, C.X.; Xu, W.; Peeters, F.M. |
| Title |
Cerenkov emission of terahertz acoustic-phonons from graphene |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
102 |
Issue |
22 |
Pages |
222101-222104 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We present a theoretical study of the electrical generation of acoustic-phonon emission from graphene at room temperature. The drift velocity (v(x)) and temperature of electrons driven by dc electric field (F-x) are determined by solving self-consistently the momentum-and energy-balance equations derived from the Boltzmann equation. We find that in the presence of impurity, acoustic-and optic-phonon scattering, v(x) can be much larger than the longitudinal (v(l)) and transverse (v(t)) sound velocities in graphene even within the linear response regime. As a result, although the acoustic Cerenkov effect cannot be obviously seen in the analytical formulas, the enhanced acoustic-phonon emission can be observed with increasing F-x when v(x) > v(l) and v > v(t). The frequency of acoustic-phonon emission from graphene can be above 10 THz, which is much higher than that generated from conventional semiconductor systems. This study is pertinent to the application of graphene as hypersonic devices such as terahertz sound sources. (C) 2013 AIP Publishing LLC. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000320621600034 |
Publication Date |
2013-06-03 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| 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 |
25 |
Open Access |
|
| Notes |
; This work was supported by the National Natural Science Foundation of China (Grant No. 10974206), Ministry of Science and Technology of China (Grant No. 2011YQ130018), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. ; |
Approved |
Most recent IF: 3.411; 2013 IF: 3.515 |
| Call Number |
UA @ lucian @ c:irua:109607 |
Serial |
305 |
| Permanent link to this record |
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| |
| Author |
Egoavil, R.; Tan, H.; Verbeeck, J.; Bals, S.; Smith, B.; Kuiper, B.; Rijnders, G.; Koster, G.; Van Tendeloo, G. |
| Title |
Atomic scale investigation of a PbTiO3/SrRuO3/DyScO3 heterostructure |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
102 |
Issue |
22 |
Pages |
223106-5 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
An epitaxial PbTiO3 thin film grown on self-organized crystalline SrRuO3 nanowires deposited on a DyScO3 substrate with ordered DyO and ScO2 chemical terminations is investigated by transmission electron microscopy. In this PbTiO3/SrRuO3/DyScO3 heterostructure, the SrRuO3 nanowires are assumed to grow on only one type of substrate termination. Here, we report on the structure, morphology, and chemical composition analysis of this heterostructure. Electron energy loss spectroscopy reveals the exact termination sequence in this complex structure. The energy loss near-edge structure of the Ti-L-2,L-3, Sc-L-2,L-3, and O K edges shows intrinsic interfacial electronic reconstruction. Furthermore, PbTiO3 domain walls are observed to start at the end of the nanowires resulting in atomic steps on the film surface. (C) 2013 AIP Publishing LLC. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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| Language |
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Wos |
000320621600070 |
Publication Date |
2013-06-05 |
| 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 |
|
Edition |
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| ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.411 |
Times cited |
12 |
Open Access |
|
| Notes |
Ifox; Esteem2; Countatoms; Vortex; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 3.411; 2013 IF: 3.515 |
| Call Number |
UA @ lucian @ c:irua:109606UA @ admin @ c:irua:109606 |
Serial |
185 |
| Permanent link to this record |
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| |
| Author |
Govaerts, K.; Saniz, R.; Partoens, B.; Lamoen, D. |
| Title |
van der Waals bonding and the quasiparticle band structure of SnO from first principles |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
87 |
Issue |
23 |
Pages |
235210-235217 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
| Abstract |
In this work we have investigated the structural and electronic properties of SnO, which is built up from layers kept together by van der Waals (vdW) forces. The combination of a vdW functional within density functional theory (DFT) and quasiparticle band structure calculations within the GW approximation provides accurate values for the lattice parameters, atomic positions, and the electronic band structure including the fundamental (indirect) and the optical (direct) band gap without the need of experimental or empirical input. A systematic comparison is made between different levels of self-consistency within the GW approach {following the scheme of Shishkin et al. [Phys. Rev. B 75, 235102 (2007)]} and the results are compared with DFT and hybrid functional results. Furthermore, the effect of the vdW-corrected functional as a starting point for the GW calculation of the band gap has been investigated. Finally, we studied the effect of the vdW functional on the electron charge density. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000321061000003 |
Publication Date |
2013-07-01 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
50 |
Open Access |
|
| Notes |
IWT; FWO; Hercules |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
| Call Number |
UA @ lucian @ c:irua:109596 |
Serial |
3835 |
| Permanent link to this record |
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| |
| Author |
Buekenhoudt, A.; Bisignano, F.; De Luca, G.; Vandezande, P.; Wouters, M.; Verhulst, K. |
| Title |
Unravelling the solvent flux behaviour of ceramic nanofiltration and ultrafiltration membranes |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Journal of membrane science |
Abbreviated Journal |
J Membrane Sci |
| Volume |
439 |
Issue |
|
Pages |
36-47 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Applied Electrochemistry & Catalysis (ELCAT) |
| Abstract |
In order to increase the understanding of the underlying processes in organic solvent nanofiltration (OSN), a study has been undertaken aimed at clarifying the solvent flux behaviour of ceramic nanofiltration and ultrafiltration membranes. Ceramic membranes were chosen for their non-swelling character. Pure water and a variation of 11 different organic solvents were measured on a series of different ceramic membranes with pore-size diameters ranging from 0.9 nm up to 100 nm. To avoid any historical effects, each flux measurement was carried out on a new membrane. The flux results were analysed in a phenomenological way, and a common very simple linear relationship was observed between the product of flux and viscosity of the solvent, and the total Hansen solubility parameter of the solvent. The linear relationship was found for all membranes, independent of the membrane pore size and the membrane material. The slope of the linear relationship was found to depend exponentially on the pore-size diameter and on the polarity of the membrane surface. This result emphasizes the importance of viscosity in the solvent transport, but also of the polarity difference between membrane surface and solvent. The very simple flux model deduced, allows a straightforward prediction of the flux of any solvent or solvent mixture, once the water flux of the membrane is known. At the high pore-size end, the phenomenological model naturally transforms into the viscous-flow or pore-flow behaviour as required. A tentative physical explanation of the model takes into account the presence and extension of a water layer adsorbed to the total pore surface of these membranes. This work also shows that the water flux of a hydrophilic membrane gives a good indication of its molecular weight cut-off (MWCO), and therefore of its separation performance in water. (C)0 2013 Elsevier B.V. All rights reserved. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Amsterdam |
Editor |
|
| Language |
|
Wos |
000319501200005 |
Publication Date |
2013-03-30 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0376-7388; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.035 |
Times cited |
55 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 6.035; 2013 IF: 4.908 |
| Call Number |
UA @ lucian @ c:irua:109568 |
Serial |
3816 |
| Permanent link to this record |
| |
|
| |
| Author |
Amini, M.N.; Leenaerts, O.; Partoens, B.; Lamoen, D. |
| Title |
Graphane- and fluorographene-based quantum dots |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
| Volume |
117 |
Issue |
31 |
Pages |
16242-16247 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
| Abstract |
With the help of first-principles calculations, we investigate graphane/fluorographene heterostructures with special attention for graphane and fluorographene-based quantum dots. Graphane and fluorographene have large electronic band gaps, and we show that their band structures exhibit a strong type-II alignment. In this way, it is possible to obtain confined electron states in fluorographene nanostructures by embedding them in a graphane crystal. Bound hole states can be created in graphane domains embedded in a fluorographene environment. For circular graphane/fluorographene quantum dots, localized states can be observed in the band gap if the size of the radii is larger than approximately 4 to 5 Å. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000323082300046 |
Publication Date |
2013-07-15 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.536 |
Times cited |
14 |
Open Access |
|
| Notes |
FWO; GOW; Hercules |
Approved |
Most recent IF: 4.536; 2013 IF: 4.835 |
| Call Number |
UA @ lucian @ c:irua:109457 |
Serial |
1367 |
| Permanent link to this record |
| |
|
| |
| Author |
Shestakov, M.V.; Meledina, M.; Turner, S.; Tikhomirov, V.K.; Verellen, N.; Rodríguez, V.D.; Velázquez, J.J.; Van Tendeloo, G.; Moshchalkov, V.V. |
| Title |
The size and structure of Ag particles responsible for surface plasmon effects and luminescence in Ag homogeneously doped bulk glass |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| Volume |
114 |
Issue |
7 |
Pages |
073102-73105 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
As-prepared and heat-treated oxyfluoride glasses, co-doped with Ag nanoclusters/nanoparticles, are prepared at 0.15 at. % Ag concentration. The as-prepared glass shows an absorption band in the UV/violet attributed to the presence of amorphous Ag nanoclusters with an average size of 1.1 nm. The luminescence spectra of the untreated glass can also be ascribed to these Ag nanoclusters. Upon heat-treatment, the clusters coalesce into Ag nanoparticles with an average size of 2.3 nm, and the glasses show an extra surface plasmon absorption band in the visible. These particles, however, cease to emit due to ascribing plasmonic properties of bulk silver. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000323510900003 |
Publication Date |
2013-08-16 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.068 |
Times cited |
19 |
Open Access |
|
| Notes |
Fwo |
Approved |
Most recent IF: 2.068; 2013 IF: 2.185 |
| Call Number |
UA @ lucian @ c:irua:109455 |
Serial |
3031 |
| Permanent link to this record |
| |
|
| |
| Author |
Bals, S.; Van Aert, S.; Van Tendeloo, G. |
| Title |
High resolution electron tomography |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Current opinion in solid state and materials science |
Abbreviated Journal |
Curr Opin Solid St M |
| Volume |
17 |
Issue |
3 |
Pages |
107-114 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Reaching atomic resolution in 3D has been the ultimate goal in the field of electron tomography for many years. Significant progress, both on the theoretical as well as the experimental side has recently resulted in several exciting examples demonstrating the ability to visualise atoms in 3D. In this paper, we will review the different steps that have pushed the resolution in 3D to the atomic level. A broad range of methodologies and practical examples together with their impact on materials science will be discussed. Finally, we will provide an outlook and will describe future challenges in the field of high resolution electron tomography. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000323869800003 |
Publication Date |
2013-03-30 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1359-0286; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.938 |
Times cited |
24 |
Open Access |
|
| Notes |
Fwo; 312483 Esteem; Countatoms; |
Approved |
Most recent IF: 6.938; 2013 IF: 7.167 |
| Call Number |
UA @ lucian @ c:irua:109454 |
Serial |
1457 |
| Permanent link to this record |
| |
|
| |
| Author |
Ustarroz, J.; Hammons, J.A.; Altantzis, T.; Hubin, A.; Bals, S.; Terryn, H. |
| Title |
A generalized electrochemical aggregative growth mechanism |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
| Volume |
135 |
Issue |
31 |
Pages |
11550-11561 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The early stages of nanocrystal nucleation and growth are still an active field of research and remain unrevealed. In this work, by the combination of aberration-corrected transmission electron microscopy (TEM) and electrochemical characterization of the electrodeposition of different metals, we provide a complete reformulation of the VolmerWeber 3D island growth mechanism, which has always been accepted to explain the early stages of metal electrodeposition and thin-film growth on low-energy substrates. We have developed a Generalized Electrochemical Aggregative Growth Mechanism which mimics the atomistic processes during the early stages of thin-film growth, by incorporating nanoclusters as building blocks. We discuss the influence of new processes such as nanocluster self-limiting growth, surface diffusion, aggregation, and coalescence on the growth mechanism and morphology of the resulting nanostructures. Self-limiting growth mechanisms hinder nanocluster growth and favor coalescence driven growth. The size of the primary nanoclusters is independent of the applied potential and deposition time. The balance between nucleation, nanocluster surface diffusion, and coalescence depends on the material and the overpotential, and influences strongly the morphology of the deposits. A small extent of coalescence leads to ultraporous dendritic structures, large surface coverage, and small particle size. Contrarily, full recrystallization leads to larger hemispherical monocrystalline islands and smaller particle density. The mechanism we propose represents a scientific breakthrough from the fundamental point of view and indicates that achieving the right balance between nucleation, self-limiting growth, cluster surface diffusion, and coalescence is essential and opens new, exciting possibilities to build up enhanced supported nanostructures using nanoclusters as building blocks. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000323019400034 |
Publication Date |
2013-06-28 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
13.858 |
Times cited |
124 |
Open Access |
|
| Notes |
Fow; Hercules |
Approved |
Most recent IF: 13.858; 2013 IF: 11.444 |
| Call Number |
UA @ lucian @ c:irua:109453 |
Serial |
1323 |
| Permanent link to this record |
| |
|
| |
| Author |
Samal, D.; Tan, H.; Molegraaf, H.; Kuiper, B.; Siemons, W.; Bals, S.; Verbeeck, J.; Van Tendeloo, G.; Takamura, Y.; Arenholz, E.; Jenkins, C.A.; Rijnders, G.; Koster, G. |
| Title |
Experimental evidence for oxygen sublattice control in polar infinite layer SrCuO2 |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
| Volume |
111 |
Issue |
9 |
Pages |
096102-96105 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
A recent theoretical study [ Phys. Rev. B 85 121411(R) (2012)] predicted a thickness limit below which ideal polar cuprates turn nonpolar driven by the associated electrostatic instability. Here we demonstrate this possibility by inducing a structural transformation from the bulk planar to chainlike structure upon reducing the SrCuO2 repeat thickness in SrCuO2/SrTiO3 superlattices with unit-cell precision. Our results, based on structural investigation by x-ray diffraction and high resolution scanning transmission electron microscopy, demonstrate that the oxygen sublattice can essentially be built by design. In addition, the electronic structure of the chainlike structure, as studied by x-ray absorption spectroscopy, shows the signature for preferential hole occupation in the Cu 3d3z2-r2 orbital, which is different from the planar case. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000323610800023 |
Publication Date |
2013-08-27 |
| 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 |
29 |
Open Access |
|
| Notes |
This work was carried out with financial support from AFOSR and EOARD project (Project No. FA8655-10-1-3077) and also supported by funding from the European Research Council under the 7th Framework Program (FP7), ERC Grant No. 246791-COUNTATOMS and ERC Starting Grant No. 278510 VORTEX. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. This work was partially funded by the European Union Council under the 7th Framework Program (FP7) Grant No. NMP3-LA-2010-246102 IFOX. The authors acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure No. 312483-ESTEEM2. Advanced Light Source is supported by the Office of Science, Office of Basic Energy Sciences of the U.S. Department of Energy (DOE) under Contract No. DE-AC02-05CH11231. Y. T. acknowledges support from the National Science Foundation (DMR-0747896). W. S. was supported by the US DOE, Basic Energy Sciences, Materials Sciences and Engineering Division. D. S. thanks Z. Zhong from Vienna University of Technology, Austria for scientific discussion. ECASJO_; |
Approved |
Most recent IF: 8.462; 2013 IF: 7.728 |
| Call Number |
UA @ lucian @ c:irua:109452UA @ admin @ c:irua:109452 |
Serial |
1140 |
| Permanent link to this record |
| |
|
| |
| Author |
Clark, L.; Béché, A.; Guzzinati, G.; Lubk, A.; Mazilu, M.; Van Boxem, R.; Verbeeck, J. |
| Title |
Exploiting lens aberrations to create electron-vortex beams |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
| Volume |
111 |
Issue |
6 |
Pages |
064801-64805 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
A model for a new electron-vortex beam production method is proposed and experimentally demonstrated. The technique calls on the controlled manipulation of the degrees of freedom of the lens aberrations to achieve a helical phase front. These degrees of freedom are accessible by using the corrector lenses of a transmission electron microscope. The vortex beam is produced through a particular alignment of these lenses into a specifically designed astigmatic state and applying an annular aperture in the condenser plane. Experimental results are found to be in good agreement with simulations. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000322921200009 |
Publication Date |
2013-08-08 |
| 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 |
66 |
Open Access |
|
| Notes |
Vortex; Esteem2; Countatoms; FWO; Esteem2jra3 ECASJO; |
Approved |
Most recent IF: 8.462; 2013 IF: 7.728 |
| Call Number |
UA @ lucian @ c:irua:109340UA @ admin @ c:irua:109340 |
Serial |
1148 |
| Permanent link to this record |
| |
|
| |
| Author |
Huijben, M.; Koster, G.; Kruize, M.K.; Wenderich, S.; Verbeeck, J.; Bals, S.; Slooten, E.; Shi, B.; Molegraaf, H.J.A.; Kleibeuker, J.E.; Van Aert, S.; Goedkoop, J.B.; Brinkman, A.; Blank, D.H.A.; Golden, M.S.; Van Tendeloo, G.; Hilgenkamp, H.; Rijnders, G.; |
| Title |
Defect engineering in oxide heterostructures by enhanced oxygen surface exchange |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
| Volume |
23 |
Issue |
42 |
Pages |
5240-5248 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| Abstract |
The synthesis of materials with well-controlled composition and structure improves our understanding of their intrinsic electrical transport properties. Recent developments in atomically controlled growth have been shown to be crucial in enabling the study of new physical phenomena in epitaxial oxide heterostructures. Nevertheless, these phenomena can be influenced by the presence of defects that act as extrinsic sources of both doping and impurity scattering. Control over the nature and density of such defects is therefore necessary to fully understand the intrinsic materials properties and exploit them in future device technologies. Here, it is shown that incorporation of a strontium copper oxide nano-layer strongly reduces the impurity scattering at conducting interfaces in oxide LaAlO3SrTiO3(001) heterostructures, opening the door to high carrier mobility materials. It is proposed that this remote cuprate layer facilitates enhanced suppression of oxygen defects by reducing the kinetic barrier for oxygen exchange in the hetero-interfacial film system. This design concept of controlled defect engineering can be of significant importance in applications in which enhanced oxygen surface exchange plays a crucial role. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
| Language |
|
Wos |
000327480900003 |
Publication Date |
2013-06-10 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1616-301X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
12.124 |
Times cited |
87 |
Open Access |
|
| Notes |
Countatoms; Vortex; Fwo; Ifox ECASJO_; |
Approved |
Most recent IF: 12.124; 2013 IF: 10.439 |
| Call Number |
UA @ lucian @ c:irua:109273UA @ admin @ c:irua:109273 |
Serial |
615 |
| Permanent link to this record |
| |
|
| |
| Author |
Amin-Ahmadi, B.; Idrissi, H.; Galceran, M.; Colla, M.S.; Raskin, J.P.; Pardoen, T.; Godet, S.; Schryvers, D. |
| Title |
Effect of deposition rate on the microstructure of electron beam evaporated nanocrystalline palladium thin films |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Thin solid films : an international journal on the science and technology of thin and thick films |
Abbreviated Journal |
Thin Solid Films |
| Volume |
539 |
Issue |
|
Pages |
145-150 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The influence of the deposition rate on the formation of growth twins in nanocrystalline Pd films deposited by electron beam evaporation is investigated using transmission electron microscopy. Statistical measurements prove that twin boundary (TB) density and volume fraction of grains containing twins increase with increasing deposition rate. A clear increase of the dislocation density was observed for the highest deposition rate of 5 Å/s, caused by the increase of the internal stress building up during deposition. Based on crystallographic orientation indexation using transmission electron microscopy, it can be concluded that a {111} crystallographic texture increases with increasing deposition rate even though the {101} crystallographic texture remains dominant. Most of the TBs are fully coherent without any residual dislocations. However, for the highest deposition rate (5 Å/s), the coherency of the TBs decreases significantly as a result of the interaction of lattice dislocations emitted during deposition with the growth TBs. The analysis of the grain boundary character of different Pd films shows that an increasing fraction of high angle grain boundaries with misorientation angles around 5565° leads to a higher potential for twin formation. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
| Language |
|
Wos |
000321111100025 |
Publication Date |
2013-05-25 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0040-6090; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.879 |
Times cited |
13 |
Open Access |
|
| Notes |
Fwo |
Approved |
Most recent IF: 1.879; 2013 IF: 1.867 |
| Call Number |
UA @ lucian @ c:irua:109268 |
Serial |
807 |
| Permanent link to this record |
| |
|
| |
| Author |
Comrie, C.M.; Ahmed, A.; Smeets, D.; Demeulemeester, J.; Turner, S.; Van Tendeloo, G.; Detavernier, C.; Vantomme, A. |
| Title |
Effect of high temperature deposition on CoSi2 phase formation |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| Volume |
113 |
Issue |
23 |
Pages |
234902-234908 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
This paper discusses the nucleation behaviour of the CoSi to CoSi2 transformation from cobalt silicide thin films grown by deposition at elevated substrate temperatures ranging from 375 °C to 600 °C. A combination of channelling, real-time Rutherford backscattering spectrometry, real-time x-ray diffraction, and transmission electron microscopy was used to investigate the effect of the deposition temperature on the subsequent formation temperature of CoSi2, its growth behaviour, and the epitaxial quality of the CoSi2 thus formed. The temperature at which deposition took place was observed to exert a significant and systematic influence on both the formation temperature of CoSi2 and its growth mechanism. CoSi films grown at the lowest temperatures were found to increase the CoSi2 nucleation temperature above that of CoSi2 grown by conventional solid phase reaction, whereas the higher deposition temperatures reduced the nucleation temperature significantly. In addition, a systematic change in growth mechanism of the subsequent CoSi2 growth occurs as a function of deposition temperature. First, the CoSi2 growth rate from films grown at the lower reactive deposition temperatures is substantially lower than that grown at higher reactive deposition temperatures, even though the onset of growth occurs at a higher temperature, Second, for deposition temperatures below 450 °C, the growth appears columnar, indicating nucleation controlled growth. Elevated deposition temperatures, on the other hand, render the CoSi2 formation process layer-by-layer which indicates enhanced nucleation of the CoSi2 and diffusion controlled growth. Our results further indicate that this observed trend is most likely related to stress and changes in microstructure introduced during reactive deposition of the CoSi film. The deposition temperature therefore provides a handle to tune the CoSi2 growth mechanism. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000321011700077 |
Publication Date |
2013-06-17 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.068 |
Times cited |
2 |
Open Access |
|
| Notes |
Fwo; Countatoms |
Approved |
Most recent IF: 2.068; 2013 IF: 2.185 |
| Call Number |
UA @ lucian @ c:irua:109266 |
Serial |
815 |
| Permanent link to this record |
| |
|
| |
| Author |
Vandenberghe, W.G.; Verhulst, A.S.; Sorée, B.; Magnus, W.; Groeseneken, G.; Smets, Q.; Heyns, M.; Fischetti, M.V. |
| Title |
Figure of merit for and identification of sub-60 mV/decade devices |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
102 |
Issue |
1 |
Pages |
013510-13514 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
A figure of merit I60 is proposed for sub-60 mV/decade devices as the highest current where the input characteristics exhibit a transition from sub- to super-60 mV/decade behavior. For sub-60 mV/decade devices to be competitive with metal-oxide-semiconductor field-effect devices, I60 has to be in the 1-10 μA/μm range. The best experimental tunnel field-effect transistors (TFETs) in the literature only have an I60 of 6×10-3 μA/μm but using theoretical simulations, we show that an I60 of up to 10 μA/μm should be attainable. It is proven that the Schottky barrier FET (SBFET) has a 60 mV/decade subthreshold swing limit while combining a SBFET and a TFET does improve performance. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000313646500132 |
Publication Date |
2013-01-12 |
| 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 |
64 |
Open Access |
|
| Notes |
; William G. Vandenberghe gratefully acknowledges the support of a Ph.D. stipend from IWT-Vlaanderen. The authors thank Danielle Leonelli, Lars-Ake Ragnarsson, and Krishna Bhuwalka for useful discussions. This work was supported by imec's Industrial Affiliation Program. ; |
Approved |
Most recent IF: 3.411; 2013 IF: 3.515 |
| Call Number |
UA @ lucian @ c:irua:109262 |
Serial |
1192 |
| Permanent link to this record |
| |
|
| |
| Author |
Pathangi, H.; Cherman, V.; Khaled, A.; Sorée, B.; Groeseneken, G.; Witvrouw, A. |
| Title |
Towards CMOS-compatible single-walled carbon nanotube resonators |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Microelectronic engineering |
Abbreviated Journal |
Microelectron Eng |
| Volume |
107 |
Issue |
|
Pages |
219-222 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
We report a totally CMOS-compatible fabrication technique to assemble horizontally suspended single-walled carbon nanotube (SWCNT) resonators. Individual SWCNTs are assembled in parallel at multiple sites by a technique called dielectrophoresis. The mechanical resonance frequencies of the suspended SWCNTs are in the range of 2035 MHz as determined from the piezoresistive response of the resonators during electrostatic actuation. The resistance of the suspended SWCNT either remains unchanged or increases or decreases significantly as a function of the actuation frequency. This can be explained by the effect the nanotube chirality has on the piezoresistive gauge factor. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| Language |
|
Wos |
000319855800040 |
Publication Date |
2012-07-02 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0167-9317; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.806 |
Times cited |
6 |
Open Access |
|
| Notes |
; ; |
Approved |
Most recent IF: 1.806; 2013 IF: 1.338 |
| Call Number |
UA @ lucian @ c:irua:109260 |
Serial |
3685 |
| Permanent link to this record |
| |
|
| |
| Author |
Neyts, E.C.; van Duin, A.C.T.; Bogaerts, A. |
| Title |
Formation of single layer graphene on nickel under far-from-equilibrium high flux conditions |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
| Volume |
5 |
Issue |
16 |
Pages |
7250-7255 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
We investigate the theoretical possibility of single layer graphene formation on a nickel surface at different substrate temperatures under far-from-equilibrium high precursor flux conditions, employing state-of-the-art hybrid reactive molecular dynamics/uniform acceptance force bias Monte Carlo simulations. It is predicted that under these conditions, the formation of a single layer graphene-like film may proceed through a combined depositionsegregation mechanism on a nickel substrate, rather than by pure surface segregation as is typically observed for metals with high carbon solubility. At 900 K and above, nearly continuous graphene layers are obtained. These simulations suggest that single layer graphene deposition is theoretically possible on Ni under high flux conditions. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
| Language |
|
Wos |
000322315600019 |
Publication Date |
2013-04-26 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2040-3364;2040-3372; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
7.367 |
Times cited |
25 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 7.367; 2013 IF: 6.739 |
| Call Number |
UA @ lucian @ c:irua:109249 |
Serial |
1264 |
| Permanent link to this record |
| |
|
| |
| 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 |
Autrique, D.; Clair, G.; L'Hermite, D.; Alexiades, V.; Bogaerts, A.; Rethfeld, B. |
| Title |
The role of mass removal mechanisms in the onset of ns-laser induced plasma formation |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| Volume |
114 |
Issue |
2 |
Pages |
023301-23310 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
The present study focuses on the role of mass removal mechanisms in ns-laser ablation. A copper sample is placed in argon, initially set at standard pressure and temperature. Calculations are performed for a 6 ns laser pulse with a wavelength of 532 nm and laser fluences up to 10 J/cm2. The transient behavior in and above the copper target is described by a hydrodynamic model. Transmission profiles and ablation depths are compared with experimental results and similar trends are found. Our calculations reveal an interesting self-inhibiting mechanism: volumetric mass removal in the supercritical region triggers plasma shielding and therefore stops proceeding. This self-limiting process indicates that volumetric mass removal does not necessarily result in large ablation depths. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000321761600006 |
Publication Date |
2013-07-08 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.068 |
Times cited |
31 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.068; 2013 IF: 2.185 |
| Call Number |
UA @ lucian @ c:irua:109237 |
Serial |
2915 |
| Permanent link to this record |
| |
|
| |
| Author |
Elliott, J.A.; Shibuta, Y.; Amara, H.; Bichara, C.; Neyts, E.C. |
| Title |
Atomistic modelling of CVD synthesis of carbon nanotubes and graphene |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
| Volume |
5 |
Issue |
15 |
Pages |
6662-6676 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
We discuss the synthesis of carbon nanotubes (CNTs) and graphene by catalytic chemical vapour deposition (CCVD) and plasma-enhanced CVD (PECVD), summarising the state-of-the-art understanding of mechanisms controlling their growth rate, chiral angle, number of layers (walls), diameter, length and quality (defects), before presenting a new model for 2D nucleation of a graphene sheet from amorphous carbon on a nickel surface. Although many groups have modelled this process using a variety of techniques, we ask whether there are any complementary ideas emerging from the different proposed growth mechanisms, and whether different modelling techniques can give the same answers for a given mechanism. Subsequently, by comparing the results of tight-binding, semi-empirical molecular orbital theory and reactive bond order force field calculations, we demonstrate that graphene on crystalline Ni(111) is thermodynamically stable with respect to the corresponding amorphous metal and carbon structures. Finally, we show in principle how a complementary heterogeneous nucleation step may play a key role in the transformation from amorphous carbon to graphene on the metal surface. We conclude that achieving the conditions under which this complementary crystallisation process can occur may be a promising method to gain better control over the growth processes of both graphene from flat metal surfaces and CNTs from catalyst nanoparticles. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
| Language |
|
Wos |
000321675600003 |
Publication Date |
2013-06-06 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2040-3364;2040-3372; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
7.367 |
Times cited |
52 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 7.367; 2013 IF: 6.739 |
| Call Number |
UA @ lucian @ c:irua:109231 |
Serial |
200 |
| Permanent link to this record |
| |
|
| |
| Author |
Abakumov, A.M.; Erni, R.; Tsirlin, A.A.; Rossell, M.D.; Batuk, D.; Nénert, G.; Van Tendeloo, G. |
| Title |
Frustrated octahedral tilting distortion in the incommensurately modulated Li3xNd2/3-xTiO3 perovskites |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| Volume |
25 |
Issue |
13 |
Pages |
2670-2683 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Perovskite-structured titanates with layered A-site ordering form remarkably complex superstructures. Using transmission electron microscopy, synchrotron X-ray and neutron powder diffraction, and ab initio structure relaxation, we present the structural solution of the incommensurately modulated Li3xNd2/3xTiO3 perovskites (x = 0.05, superspace group Pmmm(α1,1/2,0)000(1/2,β2 0)000, a = 3.831048(5) Å, b = 3.827977(4) Å, c = 7.724356(8) Å, q1 = 0.45131(8)a* + 1/2b*, q2 = 1/2a* + 0.41923(4)b*). In contrast to earlier conjectures on the nanoscale compositional phase separation in these materials, all peculiarities of the superstructure can be understood in terms of displacive modulations related to an intricate octahedral tilting pattern. It involves fragmenting the pattern of the out-of-phase tilted TiO6 octahedra around the a- and b-axes into antiphase domains, superimposed on the pattern of domains with either pronounced or suppressed in-phase tilt component around the c-axis. The octahedral tilting competes with the second order JahnTeller distortion of the TiO6 octahedra. This competition is considered as the primary driving force for the modulated structure. The A cations are suspected to play a role in this modulation affecting it mainly through the tolerance factor and the size variance. The reported crystal structure calls for a revision of the structure models proposed for the family of layered A-site ordered perovskites exhibiting a similar type of modulated structure. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000321809700015 |
Publication Date |
2013-06-04 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
9.466 |
Times cited |
23 |
Open Access |
|
| Notes |
Countatoms |
Approved |
Most recent IF: 9.466; 2013 IF: 8.535 |
| Call Number |
UA @ lucian @ c:irua:109216 |
Serial |
1292 |
| Permanent link to this record |
| |
|
| |
| Author |
Kirsanova, M.A.; Mori, T.; Maruyama, S.; Abakumov, A.M.; Van Tendeloo, G.; Olenev, A.; Shevelkov, A.V. |
| Title |
Cationic clathrate of type-III Ge172-xPxTey (y\approx21,5, x\approx2y) : synthesis, crystal structure and thermoelectric properties |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
| Volume |
52 |
Issue |
14 |
Pages |
8272-8279 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
A first germanium-based cationic clathrate of type-III, Ge129.3P42.7Te21.53, was synthesized and structurally characterized (space group P42/mnm, a = 19.948(3) Å, c = 10.440(2) Å, Z = 1). In its crystal structure, germanium and phosphorus atoms form three types of polyhedral cages centered with Te atoms. The polyhedra share pentagonal and hexagonal faces to form a 3D framework. Despite the complexity of the crystal structure, the Ge129.3P42.7Te21.53 composition corresponds to the Zintl counting scheme with a good accuracy. Ge129.3P42.7Te21.53 demonstrates semiconducting/insulating behavior of electric resistivity, high positive Seebeck coefficient (500 μV K1 at 300 K), and low thermal conductivity (<0.92 W m1 K1) within the measured temperature range. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
| Language |
|
Wos |
000322087100052 |
Publication Date |
2013-06-26 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.857 |
Times cited |
3 |
Open Access |
|
| Notes |
Countatoms |
Approved |
Most recent IF: 4.857; 2013 IF: 4.794 |
| Call Number |
UA @ lucian @ c:irua:109214 |
Serial |
301 |
| Permanent link to this record |
| |
|
| |
| Author |
Abakumov, A.M.; Batuk, M.; Tsirlin, A.A.; Tyablikov, O.A.; Sheptyakov, D.V.; Filimonov, D.S.; Pokholok, K.V.; Zhidal, V.S.; Rozova, M.G.; Antipov, E.V.; Hadermann, J.; Van Tendeloo, G.; |
| Title |
Structural and magnetic phase transitions in the AnBnO3n-2 anion-deficient perovskites Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
| Volume |
52 |
Issue |
14 |
Pages |
7834-7843 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Novel anion-deficient perovskite-based ferrites Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 were synthesized by solid-state reaction in air. Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 belong to the perovskite-based AnBnO3n2 homologous series with n = 5 and 6, respectively, with a unit cell related to the perovskite subcell ap as ap√2 × ap × nap√2. Their structures are derived from the perovskite one by slicing it with 1/2[110]p(1̅01)p crystallographic shear (CS) planes. The CS operation results in (1̅01)p-shaped perovskite blocks with a thickness of (n 2) FeO6 octahedra connected to each other through double chains of edge-sharing FeO5 distorted tetragonal pyramids which can adopt two distinct mirror-related configurations. Ordering of chains with a different configuration provides an extra level of structure complexity. Above T ≈ 750 K for Pb2Ba2BiFe5O13 and T ≈ 400 K for Pb1.5Ba2.5Bi2Fe6O16 the chains have a disordered arrangement. On cooling, a second-order structural phase transition to the ordered state occurs in both compounds. Symmetry changes upon phase transition are analyzed using a combination of superspace crystallography and group theory approach. Correlations between the chain ordering pattern and octahedral tilting in the perovskite blocks are discussed. Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 undergo a transition into an antiferromagnetically (AFM) ordered state, which is characterized by a G-type AFM ordering of the Fe magnetic moments within the perovskite blocks. The AFM perovskite blocks are stacked along the CS planes producing alternating FM and AFM-aligned FeFe pairs. In spite of the apparent frustration of the magnetic coupling between the perovskite blocks, all n = 4, 5, 6 AnFenO3n2 (A = Pb, Bi, Ba) feature robust antiferromagnetism with similar Néel temperatures of 623632 K. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
| Language |
|
Wos |
000322087100006 |
Publication Date |
2013-02-13 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.857 |
Times cited |
10 |
Open Access |
|
| Notes |
Countatoms |
Approved |
Most recent IF: 4.857; 2013 IF: 4.794 |
| Call Number |
UA @ lucian @ c:irua:109213 |
Serial |
3196 |
| Permanent link to this record |
| |
|
| |
| Author |
Lu, Y.-G.; Turner, S.; Verbeeck, J.; Janssens, S.D.; Haenen, K.; Van Tendeloo, G. |
| Title |
Local bond length variations in boron-doped nanocrystalline diamond measured by spatially resolved electron energy-loss spectroscopy |
Type |
A1 Journal article |
| Year |
2013 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
103 |
Issue |
3 |
Pages |
032105-5 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Variations in local bond length and coordination in boron-doped nanocrystalline diamond (NCD) films have been studied through changes in the fine structure of boron and carbon K-edges in electron energy-loss spectra, acquired in a scanning transmission electron microscope. The presence of high concentrations of B in pristine diamond regions and enrichment of B at defects in single NCD grains is demonstrated. Local bond length variations are evidenced through an energy shift of the carbon 1s → σ* edge at B-rich defective regions within single diamond grains, indicating an expansion of the diamond bond length at sites with local high B content. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000322146300049 |
Publication Date |
2013-07-17 |
| 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 |
15 |
Open Access |
|
| Notes |
Iap P6/42; Fwo G056810n; 262348 Esmi; 246791 Countatoms; 278510 Vortex; Fwo ECASJO_; |
Approved |
Most recent IF: 3.411; 2013 IF: 3.515 |
| Call Number |
UA @ lucian @ c:irua:109210UA @ admin @ c:irua:109210 |
Serial |
1824 |
| Permanent link to this record |
