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Records |
Links |
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Author |
Covaci, L.; Berciu, M. |
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Title |
Polaron formation in the presence of Rashba spin-orbit coupling: implications for spintronics |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys Rev Lett |
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Volume |
102 |
Issue |
18 |
Pages |
186403 |
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Keywords |
A1 Journal article |
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Abstract |
We study the effects of the Rashba spin-orbit coupling on polaron formation, using a suitable generalization of the momentum average approximation. While previous work on a parabolic band model found that spin-orbit coupling increases the effective mass, we show that the opposite holds for a tight-binding model, unless both the spin-orbit and the electron-phonon couplings are weak. It is thus possible to lower the effective mass of the polaron by increasing the spin-orbit coupling. We also show that when the spin-orbit coupling is large as compared to the phonon energy, the polaron retains only one of the spin-polarized bands in its coherent spectrum. This has major implications for the propagation of spin-polarized currents in such materials, and thus for spintronic applications. |
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Address |
Department of Physics, University of British Columbia, Vancouver, British Columbia, Canada, V6T 1Z1 |
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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 |
English |
Wos |
000265948600049 |
Publication Date |
2009-05-08 |
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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 |
0031-9007 |
ISBN |
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Additional Links |
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Impact Factor |
8.462 |
Times cited |
25 |
Open Access |
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Notes |
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Approved |
Most recent IF: 8.462; 2009 IF: 7.328 |
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Call Number |
UA @ lucian @ |
Serial |
4434 |
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Permanent link to this record |
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Author |
Tambuyzer, B.R.; Bergwerf, I.; de Vocht, N.; Reekmans, K.; Daans, J.; Jorens, P.G.; Goossens, H.; Ysebaert, D.K.; Chatterjee, S.; Van Marck, E.; Berneman, Z.N.; Ponsaerts, P. |
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Title |
Allogeneic stromal cell implantation in brain tissue leads to robust microglial activation |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Immunology and cell biology |
Abbreviated Journal |
Immunol Cell Biol |
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Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal article; Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP); Bio-Imaging lab; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Although adult and embryonic stem cell-based therapy for central nervous system (CNS) injury is being developed worldwide, less attention is given to the immunological aspects of allogeneic cell implantation in the CNS. The latter is of major importance because, from a practical point of view, future stem cell-based therapy for CNS injury will likely be performed using well-characterised allogeneic stem cell populations. In this study, we aimed to further describe the immunological mechanism leading to rejection of allogeneic bone marrow-derived stromal cells (BM-SC) after implantation in murine CNS. For this, we first investigated the impact of autologous and allogeneic BM-SC on microglia activation in vitro. Although the results indicate that both autologous and allogeneic BM-SC do not activate microglia themselves in vitro, they also do not inhibit activation of microglia after exogenous stimuli in vitro. Next, we investigated the impact of allogeneic BM-SC on microglia activation in vivo. In contrast to the in vitro observations, microglia become highly activated in vivo after implantation of allogeneic BM-SC in the CNS of immune-competent mice. Moreover, our results suggest that microglia, rather than T-cells, are the major contributors to allograft rejection in the CNS. |
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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 |
Adelaide |
Editor |
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Language |
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Wos |
000266208800003 |
Publication Date |
2009-03-17 |
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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 |
0818-9641 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.557 |
Times cited |
31 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.557; 2009 IF: 4.200 |
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Call Number |
UA @ lucian @ c:irua:74903 |
Serial |
4515 |
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Permanent link to this record |
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Author |
Batenburg, K.J.; Bals, S.; Sijbers, J.; Kübel, C.; Midgley, P.A.; Hernandez, J.C.; Kaiser, U.; Encina, E.R.; Coronado, E.A.; Van Tendeloo, G. |
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Title |
3D imaging of nanomaterials by discrete tomography |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
109 |
Issue |
6 |
Pages |
730-740 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
The field of discrete tomography focuses on the reconstruction of samples that consist of only a few different materials. Ideally, a three-dimensional (3D) reconstruction of such a sample should contain only one grey level for each of the compositions in the sample. By exploiting this property in the reconstruction algorithm, either the quality of the reconstruction can be improved significantly, or the number of required projection images can be reduced. The discrete reconstruction typically contains fewer artifacts and does not have to be segmented, as it already contains one grey level for each composition. Recently, a new algorithm, called discrete algebraic reconstruction technique (DART), has been proposed that can be used effectively on experimental electron tomography datasets. In this paper, we propose discrete tomography as a general reconstruction method for electron tomography in materials science. We describe the basic principles of DART and show that it can be applied successfully to three different types of samples, consisting of embedded ErSi2 nanocrystals, a carbon nanotube grown from a catalyst particle and a single gold nanoparticle, respectively. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000265816400005 |
Publication Date |
2009-02-01 |
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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 |
0304-3991; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
220 |
Open Access |
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Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
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Call Number |
UA @ lucian @ c:irua:74665 c:irua:74665 |
Serial |
12 |
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Permanent link to this record |
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Author |
Djoković, V.; Krsmanović, R.; Božanić, D.K.; McPherson, M.; Van Tendeloo, G.; Nair, P.S.; Georges, M.K.; Radhakrishnan, T. |
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Title |
Adsorption of sulfur onto a surface of silver nanoparticles stabilized with sago starch biopolymer |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Colloids and surfaces: B : biointerfaces |
Abbreviated Journal |
Colloid Surface B |
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Volume |
73 |
Issue |
1 |
Pages |
30-35 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Adsorption of sulfide ions onto a surface of starch capped silver nanoparticles upon addition of thioacetamide was investigated. UVvis absorption spectroscopy revealed that the adsorption of the sulfide ion on the surface of the silver nanoparticles induced damping as well as blue shift of the silver surface plasmon resonance band. Further increase in thioacetamide concentration led to shift of the resonance band toward higher wavelengths indicating the formation of the continuous Ag2S layer on the silver surface. Thus fabricated nanoparticles were investigated using electron microscopy techniques (TEM, HRTEM, and HAADF-STEM) and X-ray photoelectron spectroscopy (XPS), which confirmed their coreshell structure. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000268657500005 |
Publication Date |
2009-05-05 |
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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 |
0927-7765; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.887 |
Times cited |
41 |
Open Access |
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Notes |
Esteem 026019 |
Approved |
Most recent IF: 3.887; 2009 IF: 2.600 |
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Call Number |
UA @ lucian @ c:irua:77972 |
Serial |
66 |
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Permanent link to this record |
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Author |
Beyers, E.; Biermans, E.; Ribbens, S.; de Witte, K.; Mertens, M.; Meynen, V.; Bals, S.; Van Tendeloo, G.; Vansant, E.F.; Cool, P. |
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Title |
Combined TiO2/SiO2 mesoporous photocatalysts with location and phase controllable TiO2 nanoparticles |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Applied catalysis : B : environmental |
Abbreviated Journal |
Appl Catal B-Environ |
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Volume |
88 |
Issue |
3/4 |
Pages |
515-524 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
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Abstract |
Combined TiO2/SiO2 mesoporous materials were prepared by deposition of TiO2 nanoparticles synthesised via the acid-catalysed solgel method. In the first synthesis step a titania solution is prepared, by dissolving titaniumtetraisopropoxide in nitric acid. The influences of the initial titaniumtetraisopropoxide concentration and the temperature of dissolving on the final structural properties were investigated. In the second step of the synthesis, the titania nanoparticles were deposited on a silica support. Here, the influence of the temperature during deposition was studied. The depositions were carried out on two different mesoporous silica supports, SBA-15 and MCF, leading to substantial differences in the catalytic and structural properties. The samples were analysed with N2-sorption, X-ray diffraction (XRD), electron probe microanalysis (EPMA) and transmission electron microscopy (TEM) to obtain structural information, determining the amount of titania, the crystal phase and the location of the titania particles on the mesoporous material (inside or outside the mesoporous channels). The structural differences of the support strongly determine the location of the nanoparticles and the subsequent photocatalytic activity towards the degradation of rhodamine 6G in aqueous solution under UV irradiation. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000266513400032 |
Publication Date |
2008-10-29 |
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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 |
0926-3373; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
9.446 |
Times cited |
69 |
Open Access |
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Notes |
Goa-Bof; Fwo |
Approved |
Most recent IF: 9.446; 2009 IF: 5.252 |
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Call Number |
UA @ lucian @ c:irua:77150 |
Serial |
403 |
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Permanent link to this record |
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Author |
Verbeeck, J.; Bertoni, G. |
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Title |
Deconvolution of core electron energy loss spectra |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
109 |
Issue |
11 |
Pages |
1343-1352 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Different deconvolution methods for removing multiple scattering and instrumental broadening from core loss electron energy loss spectra are compared with special attention to the artefacts they introduce. The Gaussian modifier method, Wiener filter, maximum entropy, and model based methods are described. Their performance is compared on virtual spectra where the true single scattering distribution is known. A test on experimental spectra confirms the good performance of model based deconvolution in comparison to maximum entropy methods and shows the advantage of knowing the estimated error bars from a single spectrum acquisition. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000270765800005 |
Publication Date |
2009-07-01 |
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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 |
0304-3991; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
13 |
Open Access |
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Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
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Call Number |
UA @ lucian @ c:irua:79073UA @ admin @ c:irua:79073 |
Serial |
610 |
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Permanent link to this record |
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Author |
Van Aert, S.; Chang, L.Y.; Bals, S.; Kirkland, A.I.; Van Tendeloo, G. |
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Title |
Effect of amorphous layers on the interpretation of restored exit waves |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
109 |
Issue |
3 |
Pages |
237-246 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The effects of amorphous layers on the quality of exit wave restorations have been investigated. Two independently developed software implementations for exit wave restoration have been used to simulated focal series of images of SrTiO3 with amorphous carbon layers incorporated. The restored exit waves have been compared both qualitatively and quantitatively. We have shown that amorphous layers have a strong impact on the quantitative measurements of atomic column positions, however, the error in the position measurements is still in the picometer range. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000264280200005 |
Publication Date |
2008-11-15 |
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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 |
0304-3991; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
10 |
Open Access |
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Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
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Call Number |
UA @ lucian @ c:irua:76421 |
Serial |
796 |
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Permanent link to this record |
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Author |
Khalil-Allafi, J.; Amin-Ahmadi, B. |
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Title |
The effect of chemical composition on enthalpy and entropy changes of martensitic transformations in binary NiTi shape memory alloys |
Type |
P3 Proceeding |
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Year |
2009 |
Publication |
Journal Of Alloys And Compounds |
Abbreviated Journal |
J Alloy Compd |
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Volume |
487 |
Issue |
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Pages |
363-366 |
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Keywords |
P3 Proceeding; Condensed Matter Theory (CMT) |
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Abstract |
In the present research work the binary NiTi alloys with various compositions in the range of 50.351 at.% Ni were used. Samples have been annealed at 850 °C for 15 min and then quenched in water. In order to characterize transformation temperatures and enthalpy changes of the forward and the reverse martensitic transformation, Differential Scanning Calorimetric (DSC) experiments were performed. The enthalpy and entropy changes as a function of Ni atomic content have been thermodynamically investigated. Results show that enthalpy and entropy changes of martensitic transformation decrease when Ni atomic content increases. The variation of enthalpy and entropy of martensitic transformation with Ni content in binary NiTi alloys were explained by thermodynamic parameters and electron concentration of alloy (e/a) respectively. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000272521900073 |
Publication Date |
2009-07-31 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
Proceedings of the 22nd International Conference on the Physics of Semiconductors |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0925-8388; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.133 |
Times cited |
30 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.133; 2009 IF: 2.135 |
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Call Number |
UA @ lucian @ c:irua:122040 |
Serial |
804 |
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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. |
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Title |
Formation of a combined micro- and mesoporous material using zeolite Beta nanoparticles |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Microporous and mesoporous materials: zeolites, clays, carbons and related materials |
Abbreviated Journal |
Micropor Mesopor Mat |
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Volume |
120 |
Issue |
1/2 |
Pages |
29-34 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) |
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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. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000264619200006 |
Publication Date |
2008-09-12 |
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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 |
1387-1811; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.615 |
Times cited |
42 |
Open Access |
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Notes |
Crp; Sfr Ua |
Approved |
Most recent IF: 3.615; 2009 IF: 2.652 |
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Call Number |
UA @ lucian @ c:irua:74950 |
Serial |
1254 |
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Permanent link to this record |
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Author |
Verbeeck, J.; Sc hattschneider, P.; Rosenauer, A. |
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Title |
Image simulation of high resolution energy filtered TEM images |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
109 |
Issue |
4 |
Pages |
350-360 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Inelastic image simulation software is presented, implementing the double channeling approximation which takes into account the combination of multiple elastic and single inelastic scattering in a crystal. The approach is described with a density matrix formalism. Two applications in high resolution energy filtered (EFTEM) transmission electron microscopy (TEM) images are presented: thickness-defocus maps for SrTiO3 and exit plane intensities for an (LaAlO3)3(SrTiO3)3 multilayer system. Both systems show a severe breakdown in direct interpretability which becomes worse for higher acceleration voltages, thicker samples and lower excitation edge energies. Since this effect already occurs in the exit plane intensity, it is a fundamental limit and image simulations in EFTEM are indispensable just as they are indispensable for elastic high resolution TEM images. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000265345400009 |
Publication Date |
2009-01-17 |
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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 |
0304-3991; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
36 |
Open Access |
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Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
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Call Number |
UA @ lucian @ c:irua:77272UA @ admin @ c:irua:77272 |
Serial |
1552 |
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Permanent link to this record |
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Author |
van den Broek, W.; Van Aert, S.; van Dyck, D. |
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Title |
A model based atomic resolution tomographic algorithm |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
109 |
Issue |
12 |
Pages |
1485-1490 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
Tomography with high angular annular dark field scanning transmission electron microscopy at atomic resolution can be greatly improved if one is able to take advantage of prior knowledge. In this paper we present a reconstruction technique that explicitly takes into account the microscope parameters and the atomic nature of the projected object. This results in a more accurate estimate of the atomic positions and in a good resistance to noise. The reconstruction is a maximum likelihood estimator of the object. Moreover, the limits to the precision have been explored, allowing for a prediction of the amount of expected noise in the reconstruction for a certain experimental setup. We believe that the proposed reconstruction technique can be generalized to other tomographic experiments. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000271840200010 |
Publication Date |
2009-08-28 |
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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 |
0304-3991; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
17 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
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Call Number |
UA @ lucian @ c:irua:78588 |
Serial |
2097 |
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Permanent link to this record |
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Author |
Koblischka, M.R.; Winter, M.; Das, P.; Koblischka-Veneva, A.; Muralidhar, M.; Wolf, T.; Babu, N.H.; Turner, S.; Van Tendeloo, G.; Hartmann, U. |
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Title |
Observation of nanostripes and -clusters in (Nd, EuGd)Ba2Cu3Ox superconductors |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
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Volume |
469 |
Issue |
4 |
Pages |
168-176 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
Nanostripes are observed in melt-textured and single-crystalline samples of the ternary light rare earth (LRE)-compound (Nd0.33Eu0.33Gd0.33)Ba2Cu3Ox (NEG) by means of atomic force microscopy, scanning tunnelling microscopy at ambient conditions, combined with transmission electron microscopy and electron backscatter diffraction. This enables the observation of several important features: The nanostripes are formed by chains of nanoclusters, representing the LRE/Ba substitution. The dimensions of the nanostripes are similar for both types of NEG samples. The periodicity of the nanostripes is found to range between 40 and 60 nm; the shape of the nanoclusters is elliptic with a major axis length between 300 and 500 nm and a minor axis length of about 30150 nm. The stripes are filling effectively the space in between the twin boundaries. Concerning the flux pinning, the nanoclusters are the important pinning sites, not the nanostripes themselves. |
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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 |
Amsterdam |
Editor |
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|
Language |
|
Wos |
000264657100008 |
Publication Date |
2009-01-23 |
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|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
1.404 |
Times cited |
6 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 1.404; 2009 IF: 0.723 |
|
|
Call Number |
UA @ lucian @ c:irua:76403 |
Serial |
2418 |
|
Permanent link to this record |
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|
Author |
Lamoen, D.; March, N.H. |
|
|
Title |
Orientational disorder in some molecular solids in relation to the boson peak in glasses |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Physics letters : A |
Abbreviated Journal |
Phys Lett A |
|
|
Volume |
373 |
Issue |
7 |
Pages |
799-800 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
Orientational disorder in some molecular solids is discussed in relation to the emphasis placed on transverse vibrational modes in glasses as the origin of the observed boson peak in two very recent contributions in Nature Materials. In particular, facts are here presented for (i) CH4, (ii) C60 and (iii) ethanol in their solid phases for (a) specific heat and (b) neutron scattering. The results for ethanol in particular do not fit in with the interpretation of the boson peak in terms of transverse acoustic phonons in disordered systems. Glasses will therefore have to be separated into at least two classes where the physical interpretation of the boson peak is concerned. |
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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 |
Amsterdam |
Editor |
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Language |
|
Wos |
000263515500020 |
Publication Date |
2009-01-09 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0375-9601; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
1.772 |
Times cited |
3 |
Open Access |
|
|
|
Notes |
Bof |
Approved |
Most recent IF: 1.772; 2009 IF: 2.009 |
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Call Number |
UA @ lucian @ c:irua:72917 |
Serial |
2516 |
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Permanent link to this record |
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Author |
Van Aert, S.; Verbeeck, J.; Erni, R.; Bals, S.; Luysberg, M.; van Dyck, D.; Van Tendeloo, G. |
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|
Title |
Quantitative atomic resolution mapping using high-angle annular dark field scanning transmission electron microscopy |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
109 |
Issue |
10 |
Pages |
1236-1244 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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|
Abstract |
A model-based method is proposed to relatively quantify the chemical composition of atomic columns using high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) images. The method is based on a quantification of the total intensity of the scattered electrons for the individual atomic columns using statistical parameter estimation theory. In order to apply this theory, a model is required describing the image contrast of the HAADF STEM images. Therefore, a simple, effective incoherent model has been assumed which takes the probe intensity profile into account. The scattered intensities can then be estimated by fitting this model to an experimental HAADF STEM image. These estimates are used as a performance measure to distinguish between different atomic column types and to identify the nature of unknown columns with good accuracy and precision using statistical hypothesis testing. The reliability of the method is supported by means of simulated HAADF STEM images as well as a combination of experimental images and electron energy-loss spectra. It is experimentally shown that statistically meaningful information on the composition of individual columns can be obtained even if the difference in averaged atomic number Z is only 3. Using this method, quantitative mapping at atomic resolution using HAADF STEM images only has become possible without the need of simultaneously recorded electron energy loss spectra. |
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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 |
Amsterdam |
Editor |
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Language |
|
Wos |
000270015200004 |
Publication Date |
2009-05-28 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
|
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 |
166 |
Open Access |
|
|
|
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
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|
Call Number |
UA @ lucian @ c:irua:78585UA @ admin @ c:irua:78585 |
Serial |
2748 |
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Permanent link to this record |
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Author |
Schattschneider, P.; Verbeeck, J.; Hamon, A.L. |
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Title |
Real space maps of atomic transitions |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
109 |
Issue |
7 |
Pages |
781-787 |
|
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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|
Abstract |
Considering the rapid technical development of transmission electron microscopes, we investigate the possibility to map electronic transitions in real space on the atomic scale. To this purpose, we analyse the information carried by the scatterer's initial and final state wave functions and the role of the different atomic transition channels for the inelastic scattering cross section. It is shown that the change in the magnetic quantum number in the transition can be mapped. Two experimental set-ups are proposed, one blocking half the diffraction plane, the other one using a cylinder lens for imaging. Both methods break the conventional circular symmetry in the electron microscope making it possible to detect the handedness of electronic transitions as an asymmetry in the image intensity. This finding is of important for atomic resolution energy-loss magnetic chiral dichroism (EMCD), allowing to obtain the magnetic moments of single atoms. |
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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 |
Amsterdam |
Editor |
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Language |
|
Wos |
000266787900002 |
Publication Date |
2009-03-01 |
|
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
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 |
10 |
Open Access |
|
|
|
Notes |
J.V. acknowledges the FWO-Vlaanderen for support (contract no. G.0147.06) and the European Union under the Framework 6 program under a contract for an Integrated Infrastructure Initiative. Reference 026019 ESTEEM. |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
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Call Number |
UA @ lucian @ c:irua:77360UA @ admin @ c:irua:77360 |
Serial |
2829 |
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Permanent link to this record |
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Author |
Müller, K.; Schowalter, M.; Jansen, J.; Tsuda, K.; Titantah, J.; Lamoen, D.; Rosenauer, A. |
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Title |
Refinement of the 200 structure factor for GaAs using parallel and convergent beam electron nanodiffraction data |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
109 |
Issue |
7 |
Pages |
802-814 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We present a new method to measure structure factors from electron spot diffraction patterns recorded under almost parallel illumination in transmission electron microscopes. Bloch wave refinement routines have been developed to refine the crystal thickness, its orientation and structure factors by comparison of experimentally recorded and calculated intensities. Our method requires a modicum of computational effort, making it suitable for contemporary personal computers. Frozen lattice and Bloch wave simulations of GaAs diffraction patterns are used to derive optimised experimental conditions. Systematic errors are estimated from the application of the method to simulated diffraction patterns and rules for the recognition of physically reasonable initial refinement conditions are derived. The method is applied to the measurement of the 200 structure factor for GaAs. We found that the influence of inelastically scattered electrons is negligible. Additionally, we measured the 200 structure factor from zero loss filtered two-dimensional convergent beam electron diffraction patterns. The precision of both methods is found to be comparable and the results agree well with each other. A deviation of more than 20% from isolated atom scattering data is observed, whereas close agreement is found with structure factors obtained from density functional theory [A. Rosenauer, M. Schowalter, F. Glas, D. Lamoen, Phys. Rev. B 72 (2005), 085326-1], which account for the redistribution of electrons due to chemical bonding via modified atomic scattering amplitudes. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000266787900005 |
Publication Date |
2009-03-23 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
8 |
Open Access |
|
|
|
Notes |
Fwo; G.0425.05; Esteem; Ant 200611271505 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
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|
Call Number |
UA @ lucian @ c:irua:77361 |
Serial |
2856 |
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Permanent link to this record |
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Author |
Baguer, N.; Georgieva, V.; Calderin, L.; Todorov, I.T.; van Gils, S.; Bogaerts, A. |
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Title |
Study of the nucleation and growth of TiO2 and ZnO thin films by means of molecular dynamics simulations |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Journal of crystal growth |
Abbreviated Journal |
J Cryst Growth |
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Volume |
311 |
Issue |
16 |
Pages |
4034-4043 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The nucleation and growth of titanium dioxide (TiO2) and zinc oxide (ZnO) thin films on Fe2O3 (hematite), Al2O3 (á-alumina) and SiO2 (á-quartz) are studied by molecular dynamics simulations. The results show the formation of a strong interface region between the substrate and the film in the six systems studied here. A combination of polycrystalline and amorphous phases are observed in the TiO2 films grown on the three substrates. ZnO deposition on the Fe2O3 and Al2O3 crystals yields a monocrystalline film growth. The ZnO film deposited on the SiO2 crystal exhibits less crystallinity. The simulation results are compared with experimental results available in the literature. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000269580100012 |
Publication Date |
2009-06-24 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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ISSN |
0022-0248; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
1.751 |
Times cited |
23 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 1.751; 2009 IF: 1.534 |
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|
Call Number |
UA @ lucian @ c:irua:77453 |
Serial |
3338 |
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Permanent link to this record |
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Author |
Lepoittevin, C.; Malo, S.; Van Tendeloo, G.; Hervieu, M. |
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Title |
Synthesis and structural mechanisms of the 2201-type ferrites and polytypes: Fe2(Sr2-xAx)FeO6.5-\delta/2 (A = Ba, La, Tl, Pb and Bi) |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Solid state sciences |
Abbreviated Journal |
Solid State Sci |
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Volume |
11 |
Issue |
3 |
Pages |
595-607 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The Fe2(Sr2 − xAx)FeO6.5 − ä/2 systems have been investigated, by doping the iron rich 2201-type parent structure with Ba2+, La3+ and 5d10 post-transition cations. The syntheses have been carried out up to the limit of the 2201-type solid solutions, in order to test the role of the double iron layer Fe2O2.5 − ä/2. The localisation of the charge carriers in these compounds is consistent with their strong antiferro-magnetism. The investigation was then carried out in the transition part of the diagram up to the formation of stable phases. The study of structural mechanisms was carried using high resolution electron microscopy (transmission and scanning transmission), electron diffraction and energy dispersive spectroscopy. Different non-stoichiometry mechanisms are observed, depending on the electronic structure and chemical properties of the doping elements. The specific behavior of the modulated double iron layer is discussed. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000264644800001 |
Publication Date |
2008-12-26 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1293-2558; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
1.811 |
Times cited |
3 |
Open Access |
|
|
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 1.811; 2009 IF: 1.675 |
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|
Call Number |
UA @ lucian @ c:irua:76416 |
Serial |
3437 |
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Permanent link to this record |
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Author |
Ke, X.; Bals, S.; Romo Negreira, A.; Hantschel, T.; Bender, H.; Van Tendeloo, G. |
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Title |
TEM sample preparation by FIB for carbon nanotube interconnects |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
|
Volume |
109 |
Issue |
11 |
Pages |
1353-1359 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A powerful method to study carbon nanotubes (CNTs) grown in patterned substrates for potential interconnects applications is transmission electron microscopy (TEM). However, high-quality TEM samples are necessary for such a study. Here, TEM specimen preparation by focused ion beam (FIB) has been used to obtain lamellae of patterned samples containing CNTs grown inside contact holes. A dual-cap Pt protection layer and an extensive 5 kV cleaning procedure are applied in order to preserve the CNTs and avoid deterioration during milling. TEM results show that the inner shell structure of the carbon nanotubes has been preserved, which proves that focused ion beam is a useful technique to prepare TEM samples of CNT interconnects. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000270765800006 |
Publication Date |
2009-07-11 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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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 |
21 |
Open Access |
|
|
|
Notes |
Esteem 026019; Iap |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
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Call Number |
UA @ lucian @ c:irua:79074 |
Serial |
3485 |
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Permanent link to this record |
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Author |
van den Broek, W.; Verbeeck, J.; Schryvers, D.; de Backer, S.; Scheunders, P. |
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Title |
Tomographic spectroscopic imaging; an experimental proof of concept |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
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Volume |
109 |
Issue |
4 |
Pages |
296-303 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
Recording the electron energy loss spectroscopy data cube with a series of energy filtered images is a dose inefficient process because the energy slit blocks most of the electrons. When recording the data cube by scanning an electron probe over the sample, perfect dose efficiency is attained; but due to the low current in nanoprobes, this often is slower, with a smaller field of view. In W. Van den Broek et al. [Ultramicroscopy, 106 (2006) 269], we proposed a new method to record the data cube, which is more dose efficient than an energy filtered series. It produces a set of projections of the data cube and then tomographically reconstructs it. In this article, we demonstrate these projections in practice, we present a simple geometrical model that allows for quantification of the projection angles and we present the first successful experimental reconstruction, all on a standard post-column instrument. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000265345400003 |
Publication Date |
2008-12-10 |
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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 |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.843 |
Times cited |
1 |
Open Access |
|
|
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
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|
Call Number |
UA @ lucian @ c:irua:77271 |
Serial |
3671 |
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Permanent link to this record |
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Author |
Brosens, F.; Magnus, W. |
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Title |
Carrier transport in nanodevices: revisiting the Boltzmann and Wigner distribution functions |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
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Volume |
246 |
Issue |
7 |
Pages |
1656-1661 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
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Abstract |
In principle, transport of charged carriers in nanometer sized solid-state devices can be fully characterized once the non-equilibrium distribution function describing the carrier ensemble is known. In this light, we have revisited the Boltzmann and the Wigner distribution functions and the framework in which they emerge from the classical respectively quantum mechanical Liouville equation. We have assessed the method of the characteristic curves as a potential workhorse to solve the time dependent Boltzmann equation for carriers propagating through spatially non-uniform systems, such as nanodevices. In order to validate the proposed solution strategy, we numerically solve the Boltzmann equation for a one-dimensional conductor mimicking the basic features of a biased low-dimensional transistor operating in the on-state. Finally, we propose a computational scheme capable of extending the benefits of the above mentioned solution strategy when it comes to solve the Wigner-Liouville equation. |
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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 |
Berlin |
Editor |
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Language |
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Wos |
000268659100033 |
Publication Date |
2009-04-22 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0370-1972;1521-3951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
1.674 |
Times cited |
8 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 1.674; 2009 IF: 1.150 |
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|
Call Number |
UA @ lucian @ c:irua:77953 |
Serial |
284 |
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Permanent link to this record |
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Author |
Austing, D.G.; Payette, C.; Nair, S.V.; Yu, G.; Gupta, J.A.; Partoens, B.; Amaha, S.; Tarucha, S. |
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Title |
Scheme for coherently quenching resonant current in a three-level quantum dot energy level mixer |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Physica status solidi: C: conferences and critical reviews |
Abbreviated Journal |
|
|
|
Volume |
6 |
Issue |
4 |
Pages |
940-943 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We outline a scheme to create a dark state by three-level mixing that is potentially a useful tool for quantum coherent transport. Magnetic-field-induced intra-dot level mixing can lead to rich quantum superposition phenomena between three approaching single-particle states in a quantum dot when probed by the ground state of an adjacent weakly coupled quantum dot in the single-electron resonant tunnelling regime. The mixing relies on non-negligible anharmonicity and anisotropy in confining potentials of realistic quantum dots. Anti-crossing and transfer of strengths between resonances can be understood with a simple coherent level mixing model. Superposition can lead to the formation of a dark state by complete cancellation of an otherwise strong resonance. This is an all-electrical analogue of coherent population trapping seen in three-level-systems from quantum and atom optics. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Berlin |
Editor |
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Language |
|
Wos |
000266597600040 |
Publication Date |
2008-12-12 |
|
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1862-6351;1610-1642; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
|
Impact Factor |
|
Times cited |
|
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ lucian @ c:irua:86927 |
Serial |
2953 |
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Permanent link to this record |
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|
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Author |
Michel, K.H.; Verberck, B. |
|
|
Title |
Theoretical phonon dispersions in monolayers and multilayers of hexagonal boron-nitride |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
|
|
Volume |
246 |
Issue |
11/12 |
Pages |
2802-2805 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Starting from an empirical force constant model of valence interactions and calculating by Ewald's method the electrostatic force constants, we derive the dynamical matrix for a monolayer and for multilayer systems of hexagonal boron nitride (h-BN). Solution of the secular problem leads to the corresponding phonon dispersion relations. The interplay between valence forces and Coulomb forces is discussed. A comparison with previous results on graphene and graphene multilayers is made. Our spectra on the h-BN monolayer are rather similar to previous ab initio theory results. Comparison is also made with Raman and infrared experimental results. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000272904100091 |
Publication Date |
2009-11-12 |
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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 |
0370-1972; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.674 |
Times cited |
10 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.674; 2009 IF: 1.150 |
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Call Number |
UA @ lucian @ c:irua:80673 |
Serial |
3609 |
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Permanent link to this record |
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Author |
Berdiyorov, G.R.; Milošević, M.V.; Peeters, F.M. |
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Title |
Composite vortex ordering in superconducting films with arrays of blind holes |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
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Volume |
11 |
Issue |
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Pages |
013025,1-013025,20 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The pinning properties of a superconducting thin film with a square array of blind holes are studied using the nonlinear GinzburgLandau theory. Although blind holes provide a weaker pinning potential than holes (also called antidots), several novel vortex structures are predicted for different size and thickness of the blind holes. Orientational dimer and trimer vortex states as well as concentric vortex shells can nucleate in the blind holes. In addition, we predict the stabilization of giant vortices that may be located both in the pinning centers and/or at the interstitial sites, as well as the combination of giant vortices with sets of individual vortices. For large blind holes, local vortex shell structures inside the blind holes may transfer their symmetry to interstitial vortices as well. The subtle interplay of shell formation and traditional Abrikosov vortex lattices inside the blind holes is also studied for different numbers of trapped vortices. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000262932600002 |
Publication Date |
2009-01-21 |
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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 |
1367-2630; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.786 |
Times cited |
33 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.786; 2009 IF: 3.312 |
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Call Number |
UA @ lucian @ c:irua:75987 |
Serial |
441 |
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Permanent link to this record |
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Author |
Kerner, C.; Hackens, B.; Golubović, D.S.; Poli, S.; Faniel, S.; Magnus, W.; Schoenmaker, W.; Bayot, V.; Maes, H. |
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Title |
Control and readout of current-induced magnetic flux quantization in a superconducting transformer |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
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Volume |
22 |
Issue |
2 |
Pages |
025001,1-025001,4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We demonstrate a simple and robust method for inducing and detecting changes of magnetic flux quantization in the absence of an externally applied magnetic field. In our device, an isolated ring is interconnected with two access loops via permalloy cores, forming a superconducting transformer. By applying and tuning a direct current at the first access loop, the number of flux quanta trapped in the isolated ring is modified without the aid of an external field. The flux state of the isolated ring is simply detected by recording the evolution of the critical current of the second access loop. |
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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 |
Bristol |
Editor |
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Language |
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Wos |
000262786000003 |
Publication Date |
2008-12-24 |
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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 |
0953-2048;1361-6668; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.878 |
Times cited |
2 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.878; 2009 IF: 2.694 |
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Call Number |
UA @ lucian @ c:irua:76001 |
Serial |
497 |
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Permanent link to this record |
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Author |
Wang, M.; Chang, K.; Wang, L.G.; Dai, N.; Peeters, F.M. |
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Title |
Crystallographic plane tuning of charge and spin transport in semiconductor quantum wires |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
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Volume |
20 |
Issue |
36 |
Pages |
365202,1-365202,8 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We investigate theoretically the charge and spin transport in quantum wires grown along different crystallographic planes in the presence of the Rashba spinorbit interaction (RSOI) and the Dresselhaus spinorbit interaction (DSOI). We find that changing the crystallographic planes leads to a variation of the anisotropy of the conductance due to a different interplay between the RSOI and DSOI, since the DSOI is induced by bulk inversion asymmetry, which is determined by crystallographic plane. This interplay depends sensitively on the crystallographic planes, and consequently leads to the anisotropic charge and spin transport in quantum wires embedded in different crystallographic planes. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000269077000003 |
Publication Date |
2009-08-19 |
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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 |
0957-4484;1361-6528; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.44 |
Times cited |
14 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.44; 2009 IF: 3.137 |
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Call Number |
UA @ lucian @ c:irua:78933 |
Serial |
588 |
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Permanent link to this record |
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Author |
Misko, V.R.; Zhao, H.J.; Peeters, F.M.; Oboznov, V.; Dubonos, S.V.; Grigorieva, I.V. |
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Title |
Formation of vortex shells in mesoscopic superconducting squares |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
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Volume |
22 |
Issue |
3 |
Pages |
034001,1-034001,8 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We study vortex configurations in mesoscopic superconducting squares. Our theoretical approach is based on the analytical solution of the London equation using the Green's function method. The potential energy landscape found is then used in Langevin-type molecular-dynamics simulations to obtain stable vortex configurations. We show that the filling rules for vortices in squares with increasing applied magnetic field can be formulated, although in a different manner than in disks, in terms of the formation of vortex 'shells'. We discuss metastable states and the stability of the vortex configurations found with respect to variations of the material parameters and deformations of the shape of the sample. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000263564500002 |
Publication Date |
2009-01-29 |
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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 |
0953-2048;1361-6668; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.878 |
Times cited |
14 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.878; 2009 IF: 2.694 |
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Call Number |
UA @ lucian @ c:irua:76312 |
Serial |
1267 |
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Permanent link to this record |
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Author |
Engbarth, M.; Milošević, M.V.; Bending, S.J.; Nasirpouri, F. |
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Title |
Geometry-guided flux behaviour in superconducting Pb microcrystals |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
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Volume |
150 |
Issue |
5 |
Pages |
052048 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Electrochemistry offers highly flexible routes to fabrication of a wide variety of mesostructures, including three-dimensional (3D) crystallites, thin films and nanowires. Using this method we have grown various 3D superconducting Pb mesostructures with vastly different morphologies. We present here results on a truncated(half)-icosahedron with a hexagonal base and a tripod structure with a triangular base. Using Hall probe magnetometry we have obtained magnetisation curves for these structures at several temperatures and see evidence of geometry-driven flux entry and exit as well as flux trapping caused by specific sample geometries. We also observe behaviour that we interpret in terms of the formation of giant vortices, bearing in mind that bulk Pb is a type-I superconducting material. |
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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 |
Bristol |
Editor |
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Language |
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Wos |
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Publication Date |
2009-04-01 |
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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 |
1742-6588;1742-6596; |
ISBN |
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Additional Links |
UA library record |
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Impact Factor |
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Times cited |
1 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:106138 |
Serial |
1332 |
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Permanent link to this record |
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Author |
Masir, M.R.; Vasilopoulos, P.; Peeters, F.M. |
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Title |
Magnetic Kronig-Penney model for Dirac electrons in single-layer graphene |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
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Volume |
11 |
Issue |
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Pages |
095009,1-095009,21 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
he properties of Dirac electrons in a magnetic superlattice (SL) on graphene consisting of very high and thin (δ-function) barriers are investigated. We obtain the energy spectrum analytically and study the transmission through a finite number of barriers. The results are contrasted with those for electrons described by the Schrödinger equation. In addition, a collimation of an incident beam of electrons is obtained along the direction perpendicular to that of the SL. We also highlight an analogy with optical media in which the refractive index varies in space. |
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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 |
Bristol |
Editor |
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Language |
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Wos |
000270513500008 |
Publication Date |
2009-10-01 |
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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 |
1367-2630; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.786 |
Times cited |
89 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.786; 2009 IF: 3.312 |
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Call Number |
UA @ lucian @ c:irua:79241 |
Serial |
1884 |
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Permanent link to this record |
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Author |
Bultinck, E.; Bogaerts, A. |
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Title |
Particle-in-cell/Monte Carlo collisions treatment of an Ar/O2 magnetron discharge used for the reactive sputter deposition of TiOx films |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
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Volume |
11 |
Issue |
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Pages |
103010-103010,24 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The physical processes in an Ar/O2 magnetron discharge used for the reactive sputter deposition of TiOx thin films were simulated with a 2d3v particle-in-cell/Monte Carlo collisions (PIC/MCC) model. The plasma species taken into account are electrons, Ar+ ions, fast Arf atoms, metastable Arm* atoms, Ti+ ions, Ti atoms, O+ ions, O2+ ions, O− ions and O atoms. This model accounts for plasmatarget interactions, such as secondary electron emission and target sputtering, and the effects of target poisoning. Furthermore, the deposition process is described by an analytical surface model. The influence of the O2/Ar gas ratio on the plasma potential and on the species densities and fluxes is investigated. Among others, it is shown that a higher O2 pressure causes the region of positive plasma potential and the O− density to be more spread, and the latter to decrease. On the other hand, the deposition rates of Ti and O are not much affected by the O2/Ar proportion. Indeed, the predicted stoichiometry of the deposited TiOx film approaches x=2 for nearly all the investigated O2/Ar proportions. |
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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 |
Bristol |
Editor |
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Language |
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Wos |
000270820900001 |
Publication Date |
2009-10-06 |
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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 |
1367-2630; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.786 |
Times cited |
24 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.786; 2009 IF: 3.312 |
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Call Number |
UA @ lucian @ c:irua:78326 |
Serial |
2559 |
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Permanent link to this record |