Records |
Author |
Geurts, R.; Milošević, M.V.; Peeters, F.M. |
Title |
Topologically trapped vortex molecules in Bose-Einstein condensates |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Physical review : A : atomic, molecular and optical physics |
Abbreviated Journal |
Phys Rev A |
Volume |
78 |
Issue |
5 |
Pages |
053610,1-053610,5 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In a numerical experiment based on Gross-Pitaevskii formalism, we demonstrate unique topological quantum coherence in optically trapped Bose-Einstein condensates (BECs). Exploring the fact that vortices in a rotating BEC can be pinned by a geometric arrangement of laser beams, we show the parameter range in which vortex-antivortex molecules or multiquantum vortices are formed as a consequence of the optically imposed symmetry. Being low-energy states, we discuss the conditions for spontaneous nucleation of these unique molecules and their direct experimental observation, and provoke the potential use of the phase print of an antivortex or a multiquantum vortex when realized in unconventional circumstances. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000261215600127 |
Publication Date |
2008-11-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1050-2947;1094-1622; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.925 |
Times cited |
12 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.925; 2008 IF: 2.908 |
Call Number |
UA @ lucian @ c:irua:73184 |
Serial |
3679 |
Permanent link to this record |
|
|
|
Author |
Leenaerts, O.; Partoens, B.; Peeters, F.M. |
Title |
Graphene: a perfect nanoballoon |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
93 |
Issue |
19 |
Pages |
193107,1-193107,3 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We have performed a first-principles density functional theory investigation of the penetration of helium atoms through a graphene monolayer with defects. The relaxation of the graphene layer caused by the incoming helium atoms does not have a strong influence on the height of the energy barriers for penetration. For defective graphene layers, the penetration barriers decrease exponentially with the size of the defects but they are still sufficiently high that very large defects are needed to make the graphene sheet permeable for small atoms and molecules. This makes graphene a very promising material for the construction of nanocages and nanomembranes. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000260944100090 |
Publication Date |
2008-11-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-6951; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
295 |
Open Access |
|
Notes |
This work was supported by the Flemish Science Foundation (FWO-Vl), the NOI-BOF of the University of Antwerp, and the Belgian Science Policy (IAP). |
Approved |
Most recent IF: 3.411; 2008 IF: 3.726 |
Call Number |
UA @ lucian @ c:irua:73196 |
Serial |
1368 |
Permanent link to this record |
|
|
|
Author |
Georgieva, V.; Saraiva, M.; Jehanathan, N.; Lebelev, O.I.; Depla, D.; Bogaerts, A. |
Title |
Sputter-deposited Mg-Al-O thin films: linking molecular dynamics simulations to experiments |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
Volume |
42 |
Issue |
6 |
Pages |
065107,1-065107,8 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Using a molecular dynamics model the crystallinity of MgxAlyOz thin films with a variation in the stoichiometry of the thin film is studied at operating conditions similar to the experimental operating conditions of a dual magnetron sputter deposition system. The films are deposited on a crystalline or amorphous substrate. The Mg metal content in the film ranged from 100% (i.e. MgO film) to 0% (i.e. Al2O3 film). The radial distribution function and density of the films are calculated. The results are compared with x-ray diffraction and transmission electron microscopy analyses of experimentally deposited thin films by the dual magnetron reactive sputtering process. Both simulation and experimental results show that the structure of the MgAlO film varies from crystalline to amorphous when the Mg concentration decreases. It seems that the crystalline MgAlO films have a MgO structure with Al atoms in between. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000263824200024 |
Publication Date |
2009-03-03 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-3727;1361-6463; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.588 |
Times cited |
37 |
Open Access |
|
Notes |
Iwt |
Approved |
Most recent IF: 2.588; 2009 IF: 2.083 |
Call Number |
UA @ lucian @ c:irua:73246 |
Serial |
3110 |
Permanent link to this record |
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|
|
Author |
Godoi, R.H.M.; Aerts, K.; Harlay, J.; Kaegi, R.; Ro, C.-U.; Chou, L.; Van Grieken, R. |
Title |
Organic surface coating on Coccolithophores – Emiliania huxleyi: its determination and implication in the marine carbon cycle |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microchemical journal |
Abbreviated Journal |
|
Volume |
91 |
Issue |
2 |
Pages |
266-271 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Most of the marine precipitation of CaCO3 is due to the biological activities of planktonic and benthic organisms in waters largely oversaturated with respect to calcium carbonates. This saturation state is expected to decrease as CO2 increases in seawater. A conventional view in oceanography suggests that calcium carbonates organisms are preserved in oversaturated waters and dissolve only below the lysocline. However, it has be postulated that a fraction of the CaCO3 precipitated biogenically could dissolve in oversaturated waters due to the formation of microenvironments in which respired CO2 decreases the saturation state of seawater (Ù) in the vicinity of CaCO3 crystals. In the present study, cells of the coccolithophore Emiliania huxleyi obtained from laboratory cultures and field samples collected in the Gulf of Biscay, were examined using variable-energy electron-probe microanalysis, to determine the presence and thickness of their organic coating. In addition, a new approach for transferring micrometer-sized particles from a filter onto transmission electron microscope grids using manipulators was used to investigate individual coccolithophores. The dry thickness of an organic coating over the coccolithophore surface was found to range between 280 and 350 nm. The resemblance of this coating to the carbohydrates produced and released by the cell is discussed as well as their potential for constituting a microenvironment that hosts bacteria. The properties of this organic coating and its role in the preservation/dissolution and export of biogenic carbonates in the water column are one of the major issues of carbonate geochemistry. |
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 |
000264238000020 |
Publication Date |
2009-01-02 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0026-265x; 0026-265x |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:73322 |
Serial |
8346 |
Permanent link to this record |
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|
|
Author |
Marguí, E.; van Meel, K.; Van Grieken, R.; Buendía, A.; Fontás, C.; Hidalgo, M.; Queralt, I. |
Title |
Method for the determination of Pd-catalyst residues in active pharmaceutical ingredients by means of high-energy polarized-beam energy dispersive X-ray fluorescence |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Analytical chemistry |
Abbreviated Journal |
|
Volume |
81 |
Issue |
4 |
Pages |
1404-1410 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
In medicinal chemistry, Pd is perhaps the most-widely utilized precious metal, as catalyst in reactions which represent key transformations toward the synthesis of new active pharmaceutical ingredients (APIs). The disadvantage of this metal-catalyzed chemistry is that expensive and toxic metal residues are invariably left bound to the desired product. Thus, stringent regulatory guidelines exist for the amount of residual Pd that a drug candidate is allowed to contain. In this work, a rapid and simple method for the determination of Pd in API samples by high-energy polarized-beam energy dispersive X-ray fluorescence spectrometry has been developed and validated according to the specification limits of current legislation (10 mg kg−1 Pd) and the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH guidelines). Sample and calibration standards preparation includes a first step of homogenization and then, in a second step, the pressing of the powdered material into pellets without any chemical treatment. The use of several synthetic calibration standards made of cellulose to simulate the API matrix appears to be an effective means to obtain reliable calibration curves with a good spread of data points over the working range. With the use of the best measuring conditions, the limit of detection (0.11 mg kg−1 Pd) as well as the limit of quantitation (0.37 mg kg−1 Pd) achieved meet rigorous requirements. The repeatability of the XRF measurement appeared to be less than 2%, while the precision of the whole method was around 7%. Trueness was evaluated by analyzing spiked API samples at the level of the specification limit and calculating the recovery factor, which was better than 95%. To study the applicability of the developed methodology for the intended purpose, three batches of the studied API were analyzed for their Pd content, and the attained results were comparable to those obtained by the daily routine method (acid digestion plus atomic spectroscopy) used in most pharmaceutical laboratories. |
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 |
000263319000015 |
Publication Date |
2009-01-22 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:74340 |
Serial |
8220 |
Permanent link to this record |
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|
Author |
Dik, J.; Janssens, K.; van der Snickt, G.; van der Loeff, L.; Rickers, K.; Cotte, M. |
Title |
Visualization of a lost painting by Vincent van Gogh using synchrotron radiation based X-ray fluorescence elemental mapping |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
80 |
Issue |
16 |
Pages |
6436-6442 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Vincent van Gogh (1853−1890), one of the founding fathers of modern painting, is best known for his vivid colors, his vibrant painting style, and his short but highly productive career. His productivity is even higher than generally realized, as many of his known paintings cover a previous composition. This is thought to be the case in one-third of his early period paintings. Van Gogh would often reuse the canvas of an abandoned painting and paint a new or modified composition on top. These hidden paintings offer a unique and intimate insight into the genesis of his works. Yet, current museum-based imaging tools are unable to properly visualize many of these hidden images. We present the first-time use of synchrotron radiation based X-ray fluorescence mapping, applied to visualize a womans head hidden under the work Patch of Grass by Van Gogh. We recorded decimeter-scale, X-ray fluorescence intensity maps, reflecting the distribution of specific elements in the paint layers. In doing so we succeeded in visualizing the hidden face with unprecedented detail. In particular, the distribution of Hg and Sb in the red and light tones, respectively, enabled an approximate color reconstruction of the flesh tones. This reconstruction proved to be the missing link for the comparison of the hidden face with Van Goghs known paintings. Our approach literally opens up new vistas in the nondestructive study of hidden paint layers, which applies to the oeuvre of Van Gogh in particular and to old master paintings in general. |
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 |
000258448100039 |
Publication Date |
2008-07-29 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-2700; 5206-882x |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
178 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 6.32; 2008 IF: 5.712 |
Call Number |
UA @ admin @ c:irua:74466 |
Serial |
5906 |
Permanent link to this record |
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|
Author |
Terzano, R.; Spagnuolo, M.; Ruggiero, P.; Vekemans, B.; Scoonjans, T.; Vincze, L.; Janssens, K.; Tomasi, N.; Cesco, S.; Falkenberg, G. |
Title |
Quantitative Fe determination inside tomato roots by confocal μ-XRF |
Type |
H3 Book chapter |
Year |
2008 |
Publication |
|
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
1513-1514 |
Keywords |
H3 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
|
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
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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 |
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ISBN |
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Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:74468 |
Serial |
5794 |
Permanent link to this record |
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|
|
Author |
Terzano, R.; Spagnuolo, M.; Vekemans, B.; de Nolf, W.; Janssens, K.; Falkenberg, G.; Fiore, S.; Ruggiero, P. |
Title |
Assessing the origin and fate of Cr, Ni, Cu, Zn, Pb, and V in an industrial polluted soil by combined micro-spectroscopic techniques and bulk extraction methods |
Type |
H3 Book chapter |
Year |
2008 |
Publication |
|
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
H3 Book chapter; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
|
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 |
|
ISBN |
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Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:74476 |
Serial |
5480 |
Permanent link to this record |
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|
|
Author |
Ariskin, D.A.; Schweigert, I.V.; Alexandrov, A.L.; Bogaerts, A.; Peeters, F.M. |
Title |
Modeling of chemical processes in the low pressure capacitive radio frequency discharges in a mixture of Ar/C2H2 |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
105 |
Issue |
6 |
Pages |
063305,1-063305,9 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We study the properties of a capacitive 13.56 MHz discharge with a mixture of Ar/C<sub>2</sub>H<sub>2</sub> taking into account the plasmochemistry and growth of heavy hydrocarbons. A hybrid model was developed to combine the kinetic description for electron motion and the fluid approach for negative and positive ion transports and plasmochemical processes. A significant change in plasma parameters related to injection of 5.8% portion of acetylene in argon was observed and analyzed. We found that the electronegativity of the mixture is about 30%. The densities of negatively and positively charged heavy hydrocarbons are sufficiently large to be precursors for the formation of nanoparticles in the discharge volume. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000264774000059 |
Publication Date |
2009-03-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
21 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.068; 2009 IF: 2.072 |
Call Number |
UA @ lucian @ c:irua:74496 |
Serial |
2121 |
Permanent link to this record |
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|
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Author |
Vlasov, I.I.; Barnard, A.S.; Ralchenko, V.G.; Lebedev, O.I.; Kanzyuba, M.V.; Saveliev, A.V.; Konov, V.I.; Goovaerts, E. |
Title |
Nanodiamond photoemitters based on strong narrow-band luminescence from silicon-vacancy defects |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
Volume |
21 |
Issue |
7 |
Pages |
808-812 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Nanostructured and organic optical and electronic materials (NANOrOPT) |
Abstract |
|
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000263737800012 |
Publication Date |
2008-12-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0935-9648;1521-4095; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
19.791 |
Times cited |
98 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 19.791; 2009 IF: NA |
Call Number |
UA @ lucian @ c:irua:74513 |
Serial |
2253 |
Permanent link to this record |
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|
|
Author |
Schowalter, M.; Rosenauer, A.; Titantah, J.T.; Lamoen, D. |
Title |
Temperature-dependent Debye-Waller factors for semiconductors with the wurtzite-type structure |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Acta crystallographica: section A: foundations of crystallography |
Abbreviated Journal |
Acta Crystallogr A |
Volume |
65 |
Issue |
|
Pages |
227-231 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We computed Debye-Waller factors in the temperature range from 0.1 to 1000 K for AlN, GaN, InN, ZnO and CdO with the wurtzite-type structure. The Debye-Waller factors were derived from phonon densities of states obtained from Hellmann-Feynman forces computed within the density-functional-theory formalism. The temperature dependences of the Debye-Waller factors were fitted and fit parameters are given. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Copenhagen |
Editor |
|
Language |
|
Wos |
000264927100006 |
Publication Date |
2009-03-12 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0108-7673; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.725 |
Times cited |
23 |
Open Access |
|
Notes |
Fwo G.0425.05; Esteem 026019 |
Approved |
Most recent IF: 5.725; 2009 IF: 49.926 |
Call Number |
UA @ lucian @ c:irua:74565 |
Serial |
3497 |
Permanent link to this record |
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|
|
Author |
van Oers, C.J.; Stevens, W.J.J.; Bruijn, E.; Mertens, M.; Lebedev, O.I.; Van Tendeloo, G.; Meynen, V.; Cool, P. |
Title |
Formation of a combined micro- and mesoporous material using zeolite Beta nanoparticles |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microporous and mesoporous materials: zeolites, clays, carbons and related materials |
Abbreviated Journal |
Micropor Mesopor Mat |
Volume |
120 |
Issue |
1/2 |
Pages |
29-34 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
Abstract |
Composite micro- and mesoporous materials are synthesized using zeolite Beta nanoparticles without the need for a structure directing agent to form the mesopores. This leads to important ecological and economical advantages. The influence of the way of cooling the aged nanoparticles solution on the formation of the composite materials has been studied. The materials have been characterized towards porosity by N2-sorption, towards zeolitic properties by TGA, DRIFT, XRD and TEM, towards aluminium content by EPMA. All prepared structures possess zeolitic properties. However, the method of cooling down of the aged seeds leads to differences in the porosity and intensity of the zeolitic characteristics. |
Address |
|
Corporate Author |
|
Thesis |
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Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000264619200006 |
Publication Date |
2008-09-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1387-1811; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.615 |
Times cited |
42 |
Open Access |
|
Notes |
Crp; Sfr Ua |
Approved |
Most recent IF: 3.615; 2009 IF: 2.652 |
Call Number |
UA @ lucian @ c:irua:74950 |
Serial |
1254 |
Permanent link to this record |
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|
Author |
Liu, S.; Wei, M.; Sui, X.; Cheng, X.; Cool, P.; Van Tendeloo, G. |
Title |
A scanning electron microscopy study on hollow silica microspheres: defects and influences of the synthesis composition |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of sol-gel science and technology |
Abbreviated Journal |
J Sol-Gel Sci Techn |
Volume |
49 |
Issue |
3 |
Pages |
373-379 |
Keywords |
A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Electron microscopy for materials research (EMAT) |
Abstract |
Defects on hollow silica spheres synthesized in a tetraethylorthosilicate-octylamine-HCl-H2O system were recorded by scanning microscope. Based on the results, influences of synthesis composition on the formation of these defects are discussed. It is evidenced that products prepared with different octylamine-to-tetraethylorthosilicate ratios may have surface depressions, cracks and non-hollow microspheres. However, by changing water and acid additions, these defects could be reduced or eliminated. Generally, samples synthesized with a large octylamine addition commonly exhibit surface depressions. A small octylamine or a large water addition benefits the formation of solid silica microspheres among the product. Acid, although is not indispensable for the formation of hollow spheres, helps to eliminate or reduce depressions on the hollow shells. It is explained that the added acid gives rise to a relative localized fast hydrolysis versus condensation, facilitating an easy mobility of hydrolyzed silica species, and consequently the shell surface is smoothened. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
Kluwer |
Place of Publication |
Dordrecht |
Editor |
|
Language |
|
Wos |
000263260100015 |
Publication Date |
2008-12-16 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0928-0707;1573-4846; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.575 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.575; 2009 IF: 1.393 |
Call Number |
UA @ lucian @ c:irua:74962 |
Serial |
2941 |
Permanent link to this record |
|
|
|
Author |
Zhang, X.F.; Van Tendeloo, G.; Ge, S.L.; Emmen, J.H.P.M.; Brabers, V.A.M. |
Title |
Two phase intergrowth in Bi2Sr2Ca0.6Y0.4Cu2Oy single crystals |
Type |
A1 Journal article |
Year |
1993 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
Volume |
215 |
Issue |
1/2 |
Pages |
39-50 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
In Bi2Sr2Ca0.6Y0.4Cu2Oy single crystals we have identified the intergrowth of two phases; a normal Bi2Sr2CaCu2Oy type phase with a 4.6b modulation period and a secondary,phase with a 9.4b modulation period. Both the two phases have orthorhombic basic structures with similar lattice parameters but different symmetries, i.e. Bbmb for the normal phase and Ccca for the secondary phase. The c-parameters of these two phases are found to vary independently upon changing the nominal Y content. The modulation characteristics of the secondary phase implies a close structural relation between the two phases. Both phases are discussed from a structural and a compositional point of view. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
A1993LY97800005 |
Publication Date |
2002-10-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4534; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.942 |
Times cited |
17 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:7506 |
Serial |
3785 |
Permanent link to this record |
|
|
|
Author |
Dominiczak, M.; Ruyter, A.; Limelette, P.; Monot-Laffez, I.; Giovannelli, F.; Rossell, M.D.; Van Tendeloo, G. |
Title |
Relaxation phenomena at the metal-to-insulator transition in La0.8Sr0.2MnO3 single crystals |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Solid state communications |
Abbreviated Journal |
Solid State Commun |
Volume |
148 |
Issue |
7/8 |
Pages |
340-344 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The time dependence of the resistance RAC of a La0.8Sr0.2MnO3 single crystal has been investigated in the vicinity of the metal-to-insulator transition temperature. We used local probe microscopy to show the existence, at room temperature, of coexisting clusters of micrometer size. Our analysis shows that relaxation effects can be described with a simple exponential contribution using a random resistor-network, based on phase separation between insulating and metallic domains. Our results clearly prove the existence of a percolation threshold over which no percolation path exists. Moreover, these results highlight the significant role of the remanent magnetization. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000260907800020 |
Publication Date |
2008-09-03 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0038-1098; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.554 |
Times cited |
9 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.554; 2008 IF: 1.557 |
Call Number |
UA @ lucian @ c:irua:75637 |
Serial |
2863 |
Permanent link to this record |
|
|
|
Author |
Croitoru, M.D.; van Dyck, D.; Liu, Y.Z.; Zhang, Z. |
Title |
Measurement of specimen thickness by phase change determination in TEM |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
108 |
Issue |
12 |
Pages |
1616-1622 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
A non-destructive method for measuring the thickness of thin amorphous films composed of light elements has been developed. The method employs the statistics of the phase of the electron exit wave function. The accuracy of this method has been checked numerically by the multislice method and compared with that based on the mean inner potential. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000260808300016 |
Publication Date |
2008-06-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
2 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.843; 2008 IF: 2.629 |
Call Number |
UA @ lucian @ c:irua:75643 |
Serial |
1961 |
Permanent link to this record |
|
|
|
Author |
Connolly, M.R.; Milošević, M.V.; Bending, S.J.; Tamegai, T. |
Title |
Magneto-optical imaging of flux penetration into arrays of Bi2Sr2CaCu2O8 microdisks |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
78 |
Issue |
13 |
Pages |
132501,1-132501,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We have used differential magneto-optical (MO) imaging to investigate the mixed state of superconducting Bi2Sr2CaCu2O8+ (BSCCO) microdisks fabricated on a single-crystal sample. MO difference images of the stray field distribution over a range of out-of-plane fields allow us to distinguish between flux that is penetrating the disks and that entering the underlying BSCCO platelet. We find that flux preferentially flows along linear defects into the interstitial platelet regions up to a characteristic field Hp, above which flux enters the disks. We identify this as the field of first penetration of pancake vortices over the Bean-Livingston barrier around the disks, where Hp(T) at intermediate temperatures is well described by an exponentially decaying function with a characteristic temperature T0=19 K. At a given temperature, a minority of the disks exhibit a lower penetration field and we correlate the location of these disks with the linear defects in the BSCCO crystal. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000260574200018 |
Publication Date |
2008-10-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
8 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
Call Number |
UA @ lucian @ c:irua:75658 |
Serial |
1901 |
Permanent link to this record |
|
|
|
Author |
Lepoittevin, C.; Malo, S.; Barrier, N.; Nguyen, N.; Van Tendeloo, G.; Hervieu, M. |
Title |
Long-range ordering in the Bi1-xAexFeO3-x/2 perovskites: Bi1/3Sr2/3FeO2.67 and Bi1/2Ca1/2FeO2.75 |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
Volume |
181 |
Issue |
10 |
Pages |
2601-2609 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Two-ordered perovskites, Bi1/3Sr2/3FeO2.67 and Bi1/2Ca1/2FeO2.75, have been stabilized and characterized by transmission electron microscopy, Mössbauer spectroscopy and X-ray powder diffraction techniques. They both exhibit orthorhombic superstructures, one with a≈b≈2ap and c≈3ap (S.G.: Pb2n or Pbmn) for the Sr-based compound and one with a≈b≈2ap and c≈8ap (S.G.: B222, Bmm2, B2mm or Bmmm) for the Ca-based one. The high-resolution transmission electron microscopy (HRTEM) images evidence the existence of one deficient [FeOx]∞ layer, suggesting that Bi1/3Sr2/3FeO2.67 and Bi1/2Ca1/2FeO2.75 behave differently compared to their Ln-based homolog. The HAADF-STEM images allow to propose a model of cation ordering on the A sites of the perovskite. The Mössbauer analyses confirm the trivalent state of iron and its complex environment with three types of coordination. Both compounds exhibit a high value of resistivity and the inverse molar susceptibility versus temperature curves evidence a magnetic transition at about 730 K for the Bi1/3Sr2/3FeO2.67 and a smooth reversible transition between 590 and 650 K for Bi1/2Ca1/2FeO2.75. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000260441000008 |
Publication Date |
2008-06-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-4596; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.299 |
Times cited |
27 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 2.299; 2008 IF: 1.910 |
Call Number |
UA @ lucian @ c:irua:75663 |
Serial |
1839 |
Permanent link to this record |
|
|
|
Author |
Müller, M.; Lebedev, O.I.; Fischer, R.A. |
Title |
Gas-phase loading of [Zn4O(btb)2] (MOF-177) with organometallic CVD-precursors: inclusion compounds of the type [LnM]a@MOF-177 and the formation of Cu and Pd nanoparticles inside MOF-177 |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
Volume |
18 |
Issue |
43 |
Pages |
5274-5281 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The highly porous and desolvated (activated) coordination polymer [Zn4O(btb)2] (btb = benzene-1,3,5-tribenzoate; MOF-177) was loaded with the organometallic compounds [Cp2Fe], [Cp*2Zn], [Cu(OCHMeCH2NMe2)2], [CpCuL] (L = PMe3, CNtBu) and [CpPd(3-C3H5)] via solvent-free adsorption from the gas-phase. The inclusion compounds of the type [LnM]a@MOF-177, where [LnM] indicates the respective compound and the parameter a denotes the number of molecules per formula unit of the MOF-177, were characterised by elemental analysis, FT-IR, solid-state NMR spectroscopy and by powder X-ray diffraction (PXRD). Remarkably high effective loadings of up to 11 molecules [Cp2Fe] and 10 molecules [CpPd(3-C3H5)] per cavity were determined. The analytical data prove that the host lattice and the guest molecules interact only by weak van-der-Waals forces without any significant change of the framework or the chemical nature of the included molecules. Cu nanoparticles showing the typical surface plasmon resonance at 580 nm and Pd nanoparticles of about 2.6 nm in size were formed inside the cavities of MOF-177 by the thermally activated hydrogenolysis of the inclusion compounds [CpCuCNtBu]2@MOF-177 and by photolysis of [CpPd(3-C3H5)]10@MOF-177 in an inert atmosphere (Ar). PXRD, FT-IR and NMR studies revealed that the MOF-177 matrix remained unchanged during the decomposition process of the precursors. N2 adsorption studies of the obtained materials Cu@MOF-177 (e.g. 10.6 wt.% Cu, 2309 m2 g-1) and Pd@MOF-177 (e.g. 32.5 wt.%, 1063 m2 g-1) reveal high remaining specific surface areas (Langmuir model). |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000260487300015 |
Publication Date |
2008-10-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0959-9428;1364-5501; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
65 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:75699 |
Serial |
1318 |
Permanent link to this record |
|
|
|
Author |
Khotkevych, V.V.; Milošević, M.V.; Bending, S.J. |
Title |
A scanning Hall probe microscope for high resolution magnetic imaging down to 300 mK |
Type |
A1 Journal article |
Year |
2008 |
Publication |
The review of scientific instruments |
Abbreviated Journal |
Rev Sci Instrum |
Volume |
79 |
Issue |
12 |
Pages |
123708 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We present the design, construction, and performance of a low-temperature scanning Hall probe microscope with submicron lateral resolution and a large scanning range. The detachable microscope head is mounted on the cold flange of a commercial 3He-refrigerator (Oxford Instruments, Heliox VT-50) and operates between room temperature and 300 mK. It is fitted with a three-axis slip-stick nanopositioner that enables precise in situ adjustment of the probe location within a 6×6×7 mm3 space. The local magnetic induction at the sample surface is mapped with an easily changeable microfabricated Hall probe [typically GsAs/AlGaAs or AlGaAs/InGaAs/GaAs Hall sensors with integrated scanning tunnel microscopy (STM) tunneling tips] and can achieve minimum detectable fields 10 mG/Hz1/2. The Hall probe is brought into very close proximity to the sample surface by sensing and controlling tunnel currents at the integrated STM tip. The instrument is capable of simultaneous tunneling and Hall signal acquisition in surface-tracking mode. We illustrate the potential of the system with images of superconducting vortices at the surface of a Nb thin film down to 372 mK, and also of labyrinth magnetic-domain patterns of an yttrium iron garnet film captured at room temperature. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000262224800032 |
Publication Date |
2008-12-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0034-6748; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.515 |
Times cited |
14 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.515; 2008 IF: 1.738 |
Call Number |
UA @ lucian @ c:irua:75725 |
Serial |
2942 |
Permanent link to this record |
|
|
|
Author |
Pereira, J.M.; Peeters, F.M.; Costa Filho, R.N.; Farias, G.A. |
Title |
Valley polarization due to trigonal warping on tunneling electrons in graphene |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
21 |
Issue |
4 |
Pages |
045301,1-045301,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The effect of trigonal warping on the transmission of electrons tunneling through potential barriers in graphene is investigated. We present calculations of the transmission coefficient for single and double barriers as a function of energy, incidence angle and barrier heights. The results show remarkable valley-dependent directional effects for barriers oriented parallel to the armchair or parallel to the zigzag direction. These results indicate that electrostatic gates can be used as valley filters in graphene-based devices. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000262354700004 |
Publication Date |
2008-12-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
78 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.649; 2009 IF: 1.964 |
Call Number |
UA @ lucian @ c:irua:75736 |
Serial |
3834 |
Permanent link to this record |
|
|
|
Author |
Neira, I.S.; Kolen'ko, Y.V.; Lebedev, O.I.; Van Tendeloo, G.; Gupta, H.S.; Guitián, F.; Yoshimura, M. |
Title |
An effective morphology control of hydroxyapatite crystals via hydrothermal synthesis |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
Volume |
9 |
Issue |
1 |
Pages |
466-474 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A facile urea-assisted hydrothermal synthesis and systematic characterization of hydroxyapatite (HA) with calcium nitrate tetrahydrate and diammonium hydrogen phosphate as precursors are reported. The advantage of the proposed technique over previously reported synthetic approaches is the simple but precise control of the HA crystals morphology, which is achieved by employing an intensive, stepwise, and slow thermal decomposition of urea as well as varying initial concentrations of starting reagents. Whereas the plate-, hexagonal prism- and needle-like HA particles preferentially growth along the c-axis, the smaller and fine-plate-like HA crystals demonstrate crystal growth along the (102) and (211) directions, uncommon for HA. Furthermore, it was established that the hydrothermally derived powdered products are phase-pure HA containing CO32− anions in the crystal lattice, that is, AB-type carbonated hydroxyapatite. Transmission electron microscopy (TEM) and electron diffraction (ED) of selected samples reveal that the as-prepared HA crystals are single-crystalline and exhibit a nearly defect-free microstructure. The hardness and elastic modulus of the hexagonal prism-like HA crystals have been investigated on a nanoscale using the nanoindentation technique; the observed trends are discussed. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000262332700073 |
Publication Date |
2008-11-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1528-7483;1528-7505; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.055 |
Times cited |
183 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.055; 2009 IF: 4.162 |
Call Number |
UA @ lucian @ c:irua:75740 |
Serial |
853 |
Permanent link to this record |
|
|
|
Author |
Afanasov, I.M.; Morozov, V.A.; Kepman, A.V.; Ionov, S.G.; Seleznev, A.N.; Van Tendeloo, G.; Audeev, V.V. |
Title |
Preparation, electrical and thermal properties of new exfoliated graphite-based composites |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
Volume |
47 |
Issue |
1 |
Pages |
263-270 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Exfoliated graphite samples (EG) with different bulk densities were prepared by the exfoliation of expandable graphite under a thermal shock regime. As a conductive filler, EG has been incorporated successfully into the coal tar pitch matrix by mechanical mixing. The conducting behavior of the composite was interpreted based on the percolation theory. The percolation threshold of the EG/pitch conducting composites at room temperature was as low as 1.5 wt% and did not depend on the bulk density of the EG used. By means of thermogravimetry the improvement of thermal stability of the composites in comparison with pure pitches was detected. The phenomenon was ascribed to heat shielding effect of the EG particles evidenced by matrix-assisted laser desorption/ionization mass spectrometry. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000262143500032 |
Publication Date |
2008-10-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0008-6223; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.337 |
Times cited |
42 |
Open Access |
|
Notes |
Iap-Vi |
Approved |
Most recent IF: 6.337; 2009 IF: 4.504 |
Call Number |
UA @ lucian @ c:irua:75767 |
Serial |
2701 |
Permanent link to this record |
|
|
|
Author |
Lomakov, M.V.; Istomin, S.Y.; Abakumov, A.M.; Van Tendeloo, G.; Antipov, E.V. |
Title |
Synthesis and characterization of oxygen-deficient oxides BaCo1-xYxO3-y' x = 0.15, 0.25 and 0.33, with the perovskite structure |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Solid state ionics |
Abbreviated Journal |
Solid State Ionics |
Volume |
179 |
Issue |
33/34 |
Pages |
1885-1889 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Oxygen-deficient complex cobalt oxides BaCo1 − xYxO3 − y, = 0.15, 0.25 and 0.33, with a cubic perovskite structure have been synthesized in air at 1100 °C using a citrate route. Cation composition of the compounds was confirmed by energy-dispersed X-ray (EDX) microanalysis while oxygen content was determined by iodometric titration. An electron diffraction (ED) study of the x = 0.25 and 0.33 compositions show the presence of a diffuse intensity, indicating possible short-range ordering of the B cations. It was found that the treatment of BaCo0.75Y0.25O2.55 in a humid atmosphere leads to the absorption of water vapour at the first stage. Oxygen permeation studies of the ceramic membranes of BaCo0.75Y0.25O2.55 and BaCo0.67Y0.33O2.55 with variable thickness showed high oxygen fluxes of 0.170.32 µmol/cm2/s at 950 °C. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000261870800009 |
Publication Date |
2008-06-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0167-2738; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.354 |
Times cited |
9 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.354; 2008 IF: 2.425 |
Call Number |
UA @ lucian @ c:irua:75905 |
Serial |
3415 |
Permanent link to this record |
|
|
|
Author |
Solís, C.; Rossell, M.D.; Garcia, G.; Figueras, A.; Van Tendeloo, G.; Santiso, J. |
Title |
Microstructure and high temperature transport properties of high quality epitaxial SrFeO3-\delta films |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Solid state ionics |
Abbreviated Journal |
Solid State Ionics |
Volume |
179 |
Issue |
35/36 |
Pages |
1996-1999 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We report the high temperature electronic transport properties of SrFeO3 − ä epitaxial thin films obtained by pulsed laser deposition on NdGaO3(110) substrates. The films show total conductivity higher than the bulk material and apparent activation energy of about 0.12 eV in O2, lower than reported values for SrFeO3 − ä films. The conductivity dependence with oxygen partial pressure shows a power dependence with an exponent close to + 1/4, in agreement with expected point defect equilibrium. For a given oxygen partial pressure, the temperature coefficient of resistance (TCR) shows a low positive value of about 1.52.5 10− 3 K− 1, which is still suitable for resistive oxygen sensing applications. The transport properties of the films are discussed in view of their particular microstructure. |
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 |
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Language |
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Wos |
000261904800007 |
Publication Date |
2008-07-19 |
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 |
0167-2738; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.354 |
Times cited |
10 |
Open Access |
|
Notes |
Iap V-1 |
Approved |
Most recent IF: 2.354; 2008 IF: 2.425 |
Call Number |
UA @ lucian @ c:irua:75907 |
Serial |
2053 |
Permanent link to this record |
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Author |
Masir, M.R.; Vasilopoulos, P.; Peeters, F.M. |
Title |
Wavevector filtering through single-layer and bilayer graphene with magnetic barrier structures |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
93 |
Issue |
24 |
Pages |
242103,1-242103,3 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We show that the angular range of the transmission through magnetic barrier structures can be efficiently controlled in single-layer and bilayer graphenes and this renders the structures efficient wavevector filters. As the number of magnetic barriers increases, this range shrinks, the gaps in the transmission versus energy become wider, and the conductance oscillates with the Fermi energy. |
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 |
000261896400032 |
Publication Date |
2008-12-15 |
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 |
0003-6951; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
91 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.411; 2008 IF: 3.726 |
Call Number |
UA @ lucian @ c:irua:75931 |
Serial |
3910 |
Permanent link to this record |
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Author |
Tran, M.L.; Centeno, S.P.; Hutchison, J.A.; Engelkamp, H.; Liang, D.; Van Tendeloo, G.; Sels, B.F.; Hofkens, J.; Uji-i, H. |
Title |
Control of surface plasmon localization via self-assembly of silver nanoparticles along silver nanowires |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
Volume |
130 |
Issue |
51 |
Pages |
17240-17241 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A simple and low-cost method to create metal−metal hybrid nanostructures possessing fairly regularly spaced hot-spots of surface plasmon resonances is proposed. The nanohybrid structure was prepared via self-assembly during a simple drop-casting procedure, using chemically synthesized silver nanowires and silver nanoparticles prepared in a single batch of a polyol process. Wide field illumination of these nanohybrids produced hot-spots with spacings of around 500 nm to 1 ìm. The intensity of the emission/scattering from the hot-spots fluctuates over time. The proposed structure can be useful for the development of molecular-sensors or as a substrate for surface enhanced Raman/fluorescence spectroscopy. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000263320600018 |
Publication Date |
2008-12-03 |
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 |
0002-7863;1520-5126; |
ISBN |
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Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.858 |
Times cited |
51 |
Open Access |
|
Notes |
Fwo – G.0366.06; Fwo – Iap-Vi/27 |
Approved |
Most recent IF: 13.858; 2008 IF: 8.091 |
Call Number |
UA @ lucian @ c:irua:75946 |
Serial |
498 |
Permanent link to this record |
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Author |
Pogosov, W.V.; Misko, V.R.; Zhao, H.J.; Peeters, F.M. |
Title |
Collective vortex phases in periodic plus random pinning potential |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
1 |
Pages |
014504,1-014504,12 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study theoretically the simultaneous effect of regular and random pinning potentials on the vortex lattice structure at filling factor of 1. This structure is determined by a competition between the square symmetry of regular pinning array, by the intervortex interaction favoring a triangular symmetry, and by the randomness trying to depin vortices from their regular positions. Both analytical and molecular-dynamics approaches are used. We construct a phase diagram of the system in the plane of regular and random pinning strengths and determine typical vortex lattice defects appearing in the system due to the disorder. We find that the total disordering of the vortex lattice can occur either in one step or in two steps. For instance, in the limit of weak pinning, a square lattice of pinned vortices is destroyed in two steps. First, elastic chains of depinned vortices appear in the film; but the vortex lattice as a whole remains still pinned by the underlying square array of regular pinning sites. These chains are composed into fractal-like structures. In a second step, domains of totally depinned vortices are generated and the vortex lattice depins from regular array. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000262977900092 |
Publication Date |
2009-01-06 |
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 |
1098-0121;1550-235X; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
14 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:75982 |
Serial |
386 |
Permanent link to this record |
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Author |
Masir, M.R.; Vasilopoulos, P.; Peeters, F.M. |
Title |
Tunneling, conductance, and wavevector filtering through magnetic barriers in bilayer graphene |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
3 |
Pages |
035409,1-035409,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We evaluate the transmission and conductance through magnetic barrier structures in bilayer graphene. In particular we consider a magnetic step, single and double barriers, -function barriers, as well as barrier structures that have average magnetic field equal to zero. The transmission depends strongly on the direction of the incident electron or hole wavevector and gives the possibility to construct a direction-dependent wavevector filter. The results contrast sharply with previous results on single-layer graphene. In general, the angular range of perfect transmission becomes drastically wider and the gaps narrower. This perfect transmission range decreases with the number of barriers, the barrier width, and the magnetic field. Depending on the structure, a variety of transmission resonances occur that are reflected in the conductance through the structure. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000262978200107 |
Publication Date |
2009-01-14 |
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 |
1098-0121;1550-235X; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
80 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:75983 |
Serial |
3762 |
Permanent link to this record |
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Author |
Avetisyan, A.A.; Partoens, B.; Peeters, F.M. |
Title |
Electric field tuning of the band gap in graphene multilayers |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
3 |
Pages |
035421,1-035421,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A perpendicular electric field applied to multilayers of graphene modifies the electronic structure near the K point and may induce an energy gap in the electronic spectrum. This gap is tunable by the gate voltage and its size depends on the number of layers. We use a tight-binding approach to calculate the band structure and include a self-consistent calculation in order to obtain the density of charge carriers. Results are presented for systems consisting of three and four layers of graphene. The effect of the circular asymmetry of the band structure on the gap is critically examined. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000262978200119 |
Publication Date |
2009-01-30 |
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 |
1098-0121;1550-235X; |
ISBN |
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Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
106 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:75984 |
Serial |
887 |
Permanent link to this record |