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Author Verbruggen, S.W.; Keulemans, M.; Filippousi, M.; Flahaut, D.; Van Tendeloo, G.; Lacombe, S.; Martens, J.A.; Lenaerts, S.
Title Plasmonic goldsilver alloy on TiO2 photocatalysts with tunable visible light activity Type A1 Journal article
Year 2014 Publication Applied catalysis : B : environmental Abbreviated Journal Appl Catal B-Environ
Volume 156 Issue Pages 116-121
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL)
Abstract Adaptation of the photoresponse of anatase TiO2 to match the solar spectrum is an important scientific challenge. Modification of TiO2 with noble metal nanoparticles displaying surface plasmon resonance effects is one of the promising approaches. Surface plasmon resonance typically depends on chemical composition, size, shape and spatial organization of the metal nanoparticles in contact with TiO2. AuxAg(1 − x) alloy nanoparticles display strong composition-dependent surface plasmon resonance in the visible light region of the spectrum. In this work, a general strategy is presented to prepare plasmonic TiO2-based photocatalysts with a visible light response that can be accurately tuned over a broad range of the spectrum. The application as self-cleaning material toward the degradation of stearic acid is demonstrated for a plasmonic TiO2 photocatalyst displaying visible light photoactivity at the intensity maximum of solar light around 490 nm.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000336013200014 Publication Date 2014-03-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0926-3373; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.446 Times cited 84 Open Access
Notes Flanders(FWO); Methusalem Approved Most recent IF: 9.446; 2014 IF: 7.435
Call Number UA @ lucian @ c:irua:115552 Serial 2646
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Author Kalesaki, E.; Boneschanscher, M.P.; Geuchies, J.J.; Delerue, C.; Morais Smith, C.; Evers, W.H.; Allan, G.; Altantzis, T.; Bals, S.; Vanmaekelbergh, D.
Title Preparation and study of 2-D semiconductors with Dirac type bands due to the honeycomb nanogeometry Type P1 Proceeding
Year 2014 Publication Proceedings of the Society of Photo-optical Instrumentation Engineers T2 – Proceedings of SPIE Abbreviated Journal
Volume 8981 Issue Pages 898107-898107
Keywords P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The interest in 2-dimensional systems with a honeycomb lattice and related Dirac-­type electronic bands has exceeded the prototype graphene1. Currently, 2-­dimensional atomic2,3 and nanoscale4-­8 systems are extensively investigated in the search for materials with novel electronic properties that can be tailored by geometry. The immediate question that arises is how to fabricate 2-­D semiconductors that have a honeycomb nanogeometry, and as a consequence of that, display a Dirac-­type band structure? Here, we show that atomically coherent honeycomb superlattices of rocksalt (PbSe, PbTe) and zincblende (CdSe, CdTe) semiconductors can be obtained by nanocrystal self-­assembly and facet-­to-­facet atomic bonding, and subsequent cation exchange. We present a extended structural analysis of atomically coherent 2-­D honeycomb structures that were recently obtained with self-assembly and facet-­to-­facet bonding9. We show that this process may in principle lead to three different types of honeycomb structures, one with a graphene type-­, and two others with a silicene-­type structure. Using TEM, electron diffraction, STM and GISAXS it is convincingly shown that the structures are from the silicene-­type. In the second part of this work, we describe the electronic structure of graphene-­type and silicene type honeycomb semiconductors. We present the results of advanced electronic structure calculations using the sp3d5s* atomistic tight-­binding method10. For simplicity, we focus on semiconductors with a simple and single conduction band for the native bulk semiconductor. When the 3-­D geometry is changed into 2-­D honeycomb, a conduction band structure transformation to two types of Dirac cones, one for S-­ and one for P-­orbitals, is observed. The width of the bands depends on the honeycomb period and the coupling between the nanocrystals. Furthermore, there is a dispersionless P-­orbital band, which also forms a landmark of the honeycomb structure. The effects of considerable intrinsic spin-­orbit coupling are briefly considered. For heavy-­element compounds such as CdTe, strong intrinsic spin-­‐orbit coupling opens a non-­trivial gap at the P-­orbital Dirac point, leading to a quantum Spin Hall effect10-­12. Our work shows that well known semiconductor crystals, known for centuries, can lead to systems with entirely new electronic properties, by the simple action of nanogeometry. It can be foreseen that such structures will play a key role in future opto-­electronic applications, provided that they can be fabricated in a straightforward way.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000336040600004 Publication Date 2014-03-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 2 Open Access OpenAccess
Notes This work has been supported by funding of the French National Research Agency [ANR, (ANR-­‐09-­‐BLAN-­‐0421-­‐01)], NWO and the Dutch organization FOM [Programs “Control over Functional Nanoparticle Solids” (FNPS) and “Designing Dirac Carriers in Semiconductors” Approved Most recent IF: NA
Call Number c:irua:131912 Serial 4039
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Author Liakakos, N.; Gatel, C.; Blon, T.; Altantzis, T.; Lentijo-Mozo, S.; Garcia-Marcelot, C.; Lacroix, L.M.; Respaud, M.; Bals, S.; Van Tendeloo, G.; Soulantica, K.
Title CoFe nanodumbbells : synthesis, structure, and magnetic properties Type A1 Journal article
Year 2014 Publication Nano letters Abbreviated Journal Nano Lett
Volume 14 Issue 5 Pages 2747-2754
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract We report the solution phase synthesis, the structural analysis, and the magnetic properties of hybrid nanostructures combining two magnetic metals. These nano-objects are characterized by a remarkable shape, combining Fe nanocubes on Co nanorods. The topological composition, the orientation relationship, and the growth steps have been studied by advanced electron microscopy techniques, such as HRTEM, electron tomography, and state-of-the-art 3-dimensional elemental mapping by EDX tomography. The soft iron nanocubes behave as easy nucleation centers that induce the magnetization reversal of the entire nanohybrid, leading to a drastic modification of the overall effective magnetic anisotropy.
Address
Corporate Author Thesis
Publisher Place of Publication Washington Editor
Language Wos (up) 000336074800080 Publication Date 2014-04-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984;1530-6992; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.712 Times cited 27 Open Access OpenAccess
Notes The authors thank the ANR for the project “Batmag”, the French national project EMMA (ANR12 BS10 013 01), the European Commission for the FP7 NAMDIATREAM project (EU NMP4-LA-2010-246479), and the METSA network for the HRTEM. This has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483-ESTEEM2 (Integrated Infrastructure Initiative- I3). It was also supported by Programme Investissements d’Avenir under the program ANR-11-IDEX-0002-02, reference ANR-10-LABX-0037-NEXT. The authors acknowledge financial support from European Research Council (ERC Advanced Grant # 24691-COUNTATOMS and ERC Starting Grant # 335078-COLOURATOMS).; esteem2ta; ECASSara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); Approved Most recent IF: 12.712; 2014 IF: 13.592
Call Number UA @ lucian @ c:irua:116953 Serial 377
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Author Goncalves, W.C.; Sardella, E.; Becerra, V.F.; Milošević, M.V.; Peeters, F.M.
Title Numerical solution of the time dependent Ginzburg-Landau equations for mixed (d plus s)-wave superconductors Type A1 Journal article
Year 2014 Publication Journal of mathematical physics Abbreviated Journal J Math Phys
Volume 55 Issue 4 Pages 041501
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The time-dependent Ginzburg-Landau formalism for (d + s)-wave superconductors and their representation using auxiliary fields is investigated. By using the link variable method, we then develop suitable discretization of these equations. Numerical simulations are carried out for a mesoscopic superconductor in a homogeneous perpendicular magnetic field which revealed peculiar vortex states. (C) 2014 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos (up) 000336084100001 Publication Date 2014-04-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2488;1089-7658; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.077 Times cited 6 Open Access
Notes ; We thank the Brazilian Agency FAPESP and Flemish Science Foundation (FSF) (FWO-Vlaanderen) for financial support. M. V. M. acknowledges support from the CAPES-PVE program. ; Approved Most recent IF: 1.077; 2014 IF: 1.243
Call Number UA @ lucian @ c:irua:117728 Serial 2407
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Author Neek-Amal, M.; Peeters, F.M.
Title Graphene on hexagonal lattice substrate : stress and pseudo-magnetic field Type A1 Journal article
Year 2014 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 104 Issue 17 Pages 173106
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Moire patterns in the pseudo-magnetic field and in the strain profile of graphene (GE) when put on top of a hexagonal lattice substrate are predicted from elasticity theory. The van der Waals interaction between GE and the substrate induces out-of-plane deformations in graphene which results in a strain field, and consequently in a pseudo-magnetic field. When the misorientation angle is about 0.5 degrees, a three-fold symmetric strain field is realized that results in a pseudo-magnetic field very similar to the one proposed by F. Guinea, M. I. Katsnelson, and A. K. Geim [Nature Phys. 6, 30 (2010)]. Our results show that the periodicity and length of the pseudo-magnetic field can be tuned in GE by changing the misorientation angle and substrate adhesion parameters and a considerable energy gap (23 meV) can be obtained due to out-of-plane deformation of graphene which is in the range of recent experimental measurements (20-30 meV). (C) 2014 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos (up) 000336142500066 Publication Date 2014-05-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951;1077-3118; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 14 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. M.N.-A. was supported by the EU-Marie Curie IIF postdoc Fellowship 299855. ; Approved Most recent IF: 3.411; 2014 IF: 3.302
Call Number UA @ lucian @ c:irua:117724 Serial 1375
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Author Bogaerts, A.; Neyts, E.C.; Rousseau, A.
Title Special issue on fundamentals of plasmasurface interactions Type Editorial
Year 2014 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 47 Issue 22 Pages 220301
Keywords Editorial; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract
Address
Corporate Author Thesis
Publisher Iop publishing ltd Place of Publication Bristol Editor
Language Wos (up) 000336207900001 Publication Date 2014-05-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727;1361-6463; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited 2 Open Access
Notes Approved Most recent IF: 2.588; 2014 IF: 2.721
Call Number UA @ lucian @ c:irua:116917 Serial 3068
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Author Dufour, T.; Minnebo, J.; Abou Rich, S.; Neyts, E.C.; Bogaerts, A.; Reniers, F.
Title Understanding polyethylene surface functionalization by an atmospheric He/O2 plasma through combined experiments and simulations Type A1 Journal article
Year 2014 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 47 Issue 22 Pages 224007
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract High density polyethylene surfaces were exposed to the atmospheric post-discharge of a radiofrequency plasma torch supplied in helium and oxygen. Dynamic water contact angle measurements were performed to evaluate changes in surface hydrophilicity and angle resolved x-ray photoelectron spectroscopy was carried out to identify the functional groups responsible for wettability changes and to study their subsurface depth profiles, up to 9 nm in depth. The reactions leading to the formation of CO, C = O and OC = O groups were simulated by molecular dynamics. These simulations demonstrate that impinging oxygen atoms do not react immediately upon impact but rather remain at or close to the surface before eventually reacting. The simulations also explain the release of gaseous species in the ambient environment as well as the ejection of low molecular weight oxidized materials from the surface.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos (up) 000336207900008 Publication Date 2014-05-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727;1361-6463; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited 13 Open Access
Notes Approved Most recent IF: 2.588; 2014 IF: 2.721
Call Number UA @ lucian @ c:irua:116919 Serial 3804
Permanent link to this record
 
 
Author Neyts, E.C.; Bogaerts, A.
Title Understanding plasma catalysis through modelling and simulation : a review Type A1 Journal article
Year 2014 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys
Volume 47 Issue 22 Pages 224010
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma catalysis holds great promise for environmental applications, provided that the process viability can be maximized in terms of energy efficiency and product selectivity. This requires a fundamental understanding of the various processes taking place and especially the mutual interactions between plasma and catalyst. In this review, we therefore first examine the various effects of the plasma on the catalyst and of the catalyst on the plasma that have been described in the literature. Most of these studies are purely experimental. The urgently needed fundamental understanding of the mechanisms underpinning plasma catalysis, however, may also be obtained through modelling and simulation. Therefore, we also provide here an overview of the modelling efforts that have been developed already, on both the atomistic and the macroscale, and we identify the data that can be obtained with these models to illustrate how modelling and simulation may contribute to this field. Last but not least, we also identify future modelling opportunities to obtain a more complete understanding of the various underlying plasma catalytic effects, which is needed to provide a comprehensive picture of plasma catalysis.
Address
Corporate Author Thesis
Publisher Iop publishing ltd Place of Publication Bristol Editor
Language Wos (up) 000336207900011 Publication Date 2014-05-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3727;1361-6463; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.588 Times cited 130 Open Access
Notes Approved Most recent IF: 2.588; 2014 IF: 2.721
Call Number UA @ lucian @ c:irua:116920 Serial 3803
Permanent link to this record
 
 
Author Joris, I.; Bronders, J.; van der Grift, B.; Seuntjens, P.
Title Model-based scenario analysis of the impact of remediation measures on metal leaching from soils contaminated by historic smelter emissions Type A1 Journal article
Year 2014 Publication Journal of environmental quality Abbreviated Journal
Volume 43 Issue 3 Pages 859-868
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract A spatially distributed model for leaching of Cd from the unsaturated zone was developed for the Belgian-Dutch transnational Kempen region. The model uses as input land-use maps, atmospheric deposition data, and soil data and is part of a larger regional model that simulates transport of Cd in soil, groundwater, and surface water. A new method for deriving deposition from multiple sites was validated using soil data in different wind directions. Leaching was calculated for the period 1890 to 2010 using a reconstruction of metal loads in the region. The model was able to reproduce spatial patterns of concentrations in soil and groundwater and predicted the concentration in shallow groundwater adequately well for the purpose of evaluating management options. For 42% of the data points, measurements and calculations were within the same concentration class. The model was used for forecasting under a reference scenario, an autonomous development scenario including climate change, and a scenario with implementation of remediation measures. The impact of autonomous development (under the most extreme scenario of climatic change) amounted to an increase of 10% in cumulative Cd flux after 100 yr as compared with the reference scenario. The impact of remediation measures was mainly local and is less pronounced (i.e., only 3% change in cumulative flux at the regional scale). The integrated model served as a tool to assist in developing management strategies and prioritization of remediation of the wide-spread heavy metal contamination in the region.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000336275700009 Publication Date 2014-04-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0047-2425 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:117781 Serial 8260
Permanent link to this record
 
 
Author Zhang, F.; Vanmeensel, K.; Inokoshi, M.; Batuk, M.; Hadermann, J.; Van Meerbeek, B.; Naert, I.; Vleugels, J.
Title 3Y-TZP ceramics with improved hydrothermal degradation resistance and fracture toughness Type A1 Journal article
Year 2014 Publication Journal of the European Ceramic Society Abbreviated Journal J Eur Ceram Soc
Volume 34 Issue 10 Pages 2453-2463
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Different factors such as the way of incorporating the Y2O3 stabilizer, alumina addition and sintering temperature were assessed with the goal to improve the low temperature degradation (LTD) resistance of 3Y-TZP without compromising on the mechanical properties. The degradation of hydrothermally treated specimens was studied by X-ray diffraction, micro-Raman spectroscopy and scanning electron microscopy. Decreasing the sintering temperature decreased the LTD susceptibility of 3Y-TZPs but did not allow to obtain a LTD resistant 3Y-TZP with optimized mechanical properties. Alumina addition along with the use of Y2O3 stabilizer coated starting powder allowed to combine both an excellent toughness and LTD resistance, as compared to alumina-free and stabilizer co-precipitated powder based equivalents. Transmission electron microscopy revealed that the improved LTD resistance could be attributed to the segregation of Al3+ at the grain boundary and the heterogeneously distributed Y3+ stabilizer.
Address
Corporate Author Thesis
Publisher Place of Publication Barking Editor
Language Wos (up) 000336352500033 Publication Date 2014-03-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0955-2219; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 48 Open Access
Notes Fwo G.0431.10n Approved Most recent IF: 3.411; 2014 IF: 2.947
Call Number UA @ lucian @ c:irua:117065 c:irua:117065 Serial 11
Permanent link to this record
 
 
Author Verbruggen, S.W.; Tytgat, T.; Van Passel, S.; Martens, J.A.; Lenaerts, S.
Title Cost-effectiveness analysis to assess commercial TiO2 photocatalysts for acetaldehyde degradation in air Type A1 Journal article
Year 2014 Publication Chemicke zvesti Abbreviated Journal Chem Pap
Volume 68 Issue 9 Pages 1273-1278
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract In the commercialisation of photocatalytic air purifiers, the performance as well as the cost of the catalytic material plays an important role. Where most comparative studies only regard the photocatalytic activity as a decisive parameter, in this study both activity and cost are taken into account. Using a cost-effectiveness analysis, six different commercially available TiO2-based catalysts are evaluated in terms of their activities in photocatalytic degradation of acetaldehyde as a model reaction for indoor air purification.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000336443400015 Publication Date 2014-02-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0366-6352 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.258 Times cited 10 Open Access
Notes ; S. W. V. wishes to thank the Research Foundation Flanders (FWO) for the financial support received. The authors are grateful to the University of Antwerp for supporting and funding this research. Evonik is sincerely thanked for providing catalyst samples for our experiments free of charge. All companies are thanked for providing specific pricing data. ; Approved Most recent IF: 1.258; 2014 IF: 1.468
Call Number UA @ admin @ c:irua:117297 Serial 6174
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Author Abreu, Y.; Cruz, C.M.; Pinera, I.; Leyva, A.; Cabal, A.E.; van Espen, P.; Van Remortel, N.
Title Hyperfine electric parameters calculation in Si samples implanted with 57Mn\rightarrow57Fe Type A1 Journal article
Year 2014 Publication Physica: B : condensed matter Abbreviated Journal
Volume 445 Issue Pages 1-4
Keywords A1 Journal article; Particle Physics Group; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Nowadays the electronic structure calculations allow the study of complex systems determining the hyperfine parameters measured at a probe atom, including the presence of crystalline defects. The hyperfine electric parameters have been measured by Mossbauer spectroscopy in silicon materials implanted with Mn-57 ->,Fe-57 ions, observing four main contributions to the spectra. Nevertheless, some ambiguities still remain in the Fe-57 Mossbauer spectra interpretation in this case, regarding the damage configurations and its evolution with annealing. In the present work several implantation environments are evaluated and the Fe-57 hyperfine parameters are calculated. The observed correlation among the studied local environments and the experimental observations is presented, and a tentative microscopic description of the behavior and thermal evolution of the characteristic defects local environments of the probe atoms concerning the location of vacancies and interstitial Si in the neighborhood of Fe-57 ions in substitutional and interstitial sites is proposed. (C) 2014 Elsevier B.V. All rights reserved
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000336478700001 Publication Date 2014-03-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4526; 1873-2135 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:117697 Serial 8046
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Author Bothner, D.; Seidl, R.; Misko, V.R.; Kleiner, R.; Koelle, D.; Kemmler, M.
Title Unusual commensurability effects in quasiperiodic pinning arrays induced by local inhomogeneities of the pinning site density Type A1 Journal article
Year 2014 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume 27 Issue 6 Pages 065002
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We experimentally investigate the magnetic field dependence of the critical current I-c(B) of superconducting niobium thin films patterned with periodic and quasiperiodic antidot arrays on the submicron scale. For this purpose we monitor current-voltage characteristics at different values of B and temperature T. We investigate samples with antidots positioned at the vertices of two different tilings with quasiperiodic symmetry, namely the Shield Tiling and the Tuebingen Triangle Tiling. For reference we investigate a sample with a triangular antidot lattice. We find modulations of the critical current for both quasiperiodic tilings, which have partly been predicted by numerical simulations but not observed in experiments yet. The particularity of these commensurability effects is that they correspond to magnetic field values slightly above an integer multiple of the matching field. The observed matching effects can be explained by the caging of interstitial vortices in quasiperiodically distributed cages and the formation of symmetry-induced giant vortices.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos (up) 000336494900003 Publication Date 2014-04-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.878 Times cited 7 Open Access
Notes ; This work has been supported by the European Research Council via SOCATHES and by the Deutsche Forschungsgemeinschaft via the SFB/TRR 21. DB gratefully acknowledges support by the Evangelisches Studienwerk e.V. Villigst. MK gratefully acknowledges support by the Carl-Zeiss Stiftung. VRM gratefully acknowledges support by the 'Odysseus' Program of the Flemish Government and the Flemish Science Foundation (FWO-VI). The authors thank Franco Nori for fruitful discussions on quasiperiodic pinning arrays. ; Approved Most recent IF: 2.878; 2014 IF: 2.325
Call Number UA @ lucian @ c:irua:117763 Serial 3817
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Author Morozov, V.A.; Lazoryak, B.I.; Shmurak, S.Z.; Kiselev, A.P.; Lebedev, O.I.; Gauquelin, N.; Verbeeck, J.; Hadermann, J.; Van Tendeloo, G.
Title Influence of the structure on the properties of NaxEuy(MoO4)z red phosphors Type A1 Journal article
Year 2014 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 26 Issue 10 Pages 3238-3248
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Scheelite related compounds (A',A '')(n)[(B',B '')O-4](m) with B', B '' = W and/or Mo are promising new materials for red phosphors in pc-WLEDs (phosphor-converted white-light-emitting-diode) and solid-state lasers. Cation substitution in CaMoO4 of Ca2+ by the combination of Na+ and Eu3+, with the creation of A cation vacancies, has been investigated as a factor for controlling the scheelite-type structure and the luminescent properties. Na5Eu(MoO4)(4) and NaxEu(2-x)/33+square(2-x)/3MoO4 (0.138 <= x <= 0.5) phases with a scheelite-type structure were synthesized by the solid state method; their structural characteristics were investigated using transmission electron microscopy. Contrary to powder synchrotron X-ray diffraction before, the study by electron diffraction and high resolution transmission electron microscopy in this paper revealed that Na0.286Eu0.571MoO4 has a (3 + 2)D incommensurately modulated structure and that (3 + 2)D incommensurately modulated domains are present in Na0.200Eu0.600MoO4. It also confirmed the (3 + 1)D incommensurately modulated character of Na(0.138)Eu(0.621)Mo04. The luminescent properties of all phases under near-ultraviolet (n-UV) light have been investigated. The excitation spectra of these phosphors show the strongest absorption at about 395 nm, which matches well with the commercially available n-UV-emitting GaN-based LED chip. The emission spectra indicate an intense red emission due to the D-5(0) -> F-7(2) transition of Eu3+, with local minima in the intensity at Na0.286Eu0.571MoO4 and Na0.200Eu0.600MoO4 for similar to 613 nm and similar to 616 nm bands. The phosphor Na5Eu(MoO4)(4) shows the brightest red light emission among the phosphors in the Na2MoO4-Eu2/3MoO4 system and the maximum luminescence intensity of Na5Eu(MoO4)(4) (lambda(ex) = 395 nm) in the D-5(0) -> F-7(2) transition region is close to that of the commercially used red phosphor YVO4:Eu3+ (lambda(ex) = 326 nm). Electron energy loss spectroscopy measurements revealed the influence of the structure and Na/Eu cation distribution on the number and positions of bands in the UV-optical-infrared regions of the EELS spectrum.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000336637000028 Publication Date 2014-05-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 53 Open Access
Notes Fwo G039211n; Fwo G004413n; 278510 Vortex ECASJO_; Approved Most recent IF: 9.466; 2014 IF: 8.354
Call Number UA @ lucian @ c:irua:117765UA @ admin @ c:irua:117765 Serial 1652
Permanent link to this record
 
 
Author Abakumov, A.M.; Tsirlin, A.A.; Bakaimi, I.; Van Tendeloo, G.; Lappas, A.
Title Multiple twinning as a structure directing mechanism in layered rock-salt-type oxides : NaMnO2 polymorphism, redox potentials, and magnetism Type A1 Journal article
Year 2014 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 26 Issue 10 Pages 3306-3315
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract New polymorphs of NaMnO2 have been observed using transmission electron microscopy and synchrotron X-ray powder diffraction. Coherent twin planes confined to the (NaMnO2) layers, parallel to the (10 (1) over bar) crystallographic planes of the monoclinic layered rock-salt-type alpha-NaMnO2 (O3) structure, form quasi-periodic modulated sequences, with the known alpha-and beta-NaMnO2 polymorphs as the two limiting cases. The energy difference between the polymorphic forms, estimated using a DFT-based structure relaxation, is on the scale of the typical thermal energies that results in a high degree of stacking disorder in these compounds. The results unveil the remarkable effect of the twin planes on both the magnetic and electrochemical properties. The polymorphism drives the magnetic ground state from a quasi-1D spin system for the geometrically frustrated alpha-polymorph through a two-leg spin ladder for the intermediate stacking sequence toward a quasi-2D magnet for the beta-polymorph. A substantial increase of the equilibrium potential for Na deintercalation upon increasing the concentration of the twin planes is calculated, providing a possibility to tune the electrochemical potential of the layered rock-salt ABO(2) cathodes by engineering the materials with a controlled concentration of twins.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000336637000036 Publication Date 2014-05-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 35 Open Access
Notes Approved Most recent IF: 9.466; 2014 IF: 8.354
Call Number UA @ lucian @ c:irua:117766 Serial 2232
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Author Clima, S.; Govoreanu, B.; Jurczak, M.; Pourtois, G.
Title HfOx as RRAM material : first principles insights on the working principles Type A1 Journal article
Year 2014 Publication Microelectronic engineering Abbreviated Journal Microelectron Eng
Volume 120 Issue Pages 13-18
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract First-principles simulations were employed to gain atomistic insights on the working principles of amorphous HfO2 based Resistive Random Access Memory stack: the nature of the defect responsible for the switching between the High and Low Resistive States has been unambiguously identified to be the substoichiometric Hf sites (commonly called oxygen vacancy-V-O) and the kinetics of the process have been investigated through the study of O diffusion. Also the role of each material layer in the TiN/HfO2/Hf/TiN RRAM stack and the impact of the deposition techniques have been examined: metallic Hf sputtering is needed to provide an oxygen exchange layer that plays the role of defect buffer. TiN shall be a good defect barrier for O but a bad defect buffer layer. A possible scenario to explain the device degradation (switching failure) mechanism has been proposed – the relaxation of the metastable amorphous phase towards crystalline structure leads to denser, more structured cluster that can increase the defect migration barriers. (C) 2013 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000336697300004 Publication Date 2013-08-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0167-9317; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.806 Times cited 22 Open Access
Notes Approved Most recent IF: 1.806; 2014 IF: 1.197
Call Number UA @ lucian @ c:irua:117767 Serial 3535
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Author De Schutter, B.; Devulder, W.; Schrauwen, A.; van Stiphout, K.; Perkisas, T.; Bals, S.; Vantomme, A.; Detavernier, C.
Title Phase formation in intermixed NiGe thin films : influence of Ge content and low-temperature nucleation of hexagonal nickel germanides Type A1 Journal article
Year 2014 Publication Microelectronic engineering Abbreviated Journal Microelectron Eng
Volume 120 Issue Pages 168-173
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract In this study, we focus on phase formation in intermixed NiGe thin films as they represent a simplified model of the small intermixed interface layer that is believed to form upon deposition of Ni on Ge and where initial phase formation happens. A combinatorial sputter deposition technique was used to co-deposit a range of intermixed NiGe thin films with Ge concentrations varying between 0 and 50 at.%Ge in a single deposition on both Ge (100) and inert SiO2 substrates. In situ X-ray diffraction and transmission electron microscopy where used to study phase formation. In almost the entire composition range under investigation, crystalline phases where found to be present in the as-deposited films. Between 36 and 48 at.%Ge, high-temperature hexagonal nickel germanides were found to occur metastabily below 300 °C, both on SiO2 and Ge (100) substrates. For Ge concentrations in the range between 36 and 42 at.%, this hexagonal germanide phase was even found to be present at room temperature in the as-deposited films. The results obtained in this work could provide more insight in the phase sequence of a pure Ni film on Ge.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000336697300028 Publication Date 2013-09-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0167-9317; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.806 Times cited 9 Open Access Not_Open_Access
Notes FWO project Nr. G076112N Approved Most recent IF: 1.806; 2014 IF: 1.197
Call Number UA @ lucian @ c:irua:116958 Serial 2584
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Author de Nolf, W.; Vanmeert, F.; Janssens, K.
Title XRDUA : crystalline phase distribution maps by two-dimensional scanning and tomographic (micro) X-ray powder diffraction Type A1 Journal article
Year 2014 Publication Journal of applied crystallography Abbreviated Journal
Volume 47 Issue 3 Pages 1107-1117
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Imaging of crystalline phase distributions in heterogeneous materials, either plane projected or in virtual cross sections of the object under investigation, can be achieved by scanning X-ray powder diffraction employing X-ray micro beams and X-ray-sensitive area detectors. Software exists to convert the two-dimensional powder diffraction patterns that are recorded by these detectors to one-dimensional diffractograms, which may be analysed by the broad variety of powder diffraction software developed by the crystallography community. However, employing these tools for the construction of crystalline phase distribution maps proves to be very difficult, especially when employing micro-focused X-ray beams, as most diffraction software tools have mainly been developed having structure solution in mind and are not suitable for phase imaging purposes. XRDUA has been developed to facilitate the execution of the complete sequence of data reduction and interpretation steps required to convert large sequences of powder diffraction patterns into a limited set of crystalline phase maps in an integrated fashion.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000336738500031 Publication Date 2014-05-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8898 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 62 Open Access
Notes ; The authors would like to thank the synchrotron beamline staff at ID15 (ESRF, Grenoble, France), MicroXAS (SLS, Villigen, Switzerland) and PO6/BL-L (Petra III/Hasylab, Hamburg, Germany) for accommodating the experiments presented in this paper. Support from FWO 'Big Science' project G0C1213N as well as from the BELSPO project 'S2ART' (SD/RI/04A) is acknowledged. ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:117758 Serial 5920
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Author Zhao, C.X.; Xu, W.; Dong, H.M.; Peeters, F.M.
Title Plasmon and coupled plasmon-phonon modes in graphene in the presence of a driving electric field Type A1 Journal article
Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 89 Issue 19 Pages 195447
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present a theoretical study of the plasmon and coupled plasmon-phonon modes induced by intraband electron-electron interaction in graphene in the presence of driving dc electric field. We find that the electric field dependence of these collective excitation modes in graphene differs significantly from that in a conventional two-dimensional electron gas with a parabolic energy spectrum. This is due mainly to the fact that graphene has a linear energy spectrum and the Fermi velocity of electrons in graphene is much larger than the drift velocity of electrons. The obtained results demonstrate that the plasmon and coupled plasmon-phonon modes in graphene can be tuned by applying not only the gate voltage but also the source-to-drain field. The manipulation of plasmon and coupled plasmon-phonon modes by source-to-drain voltage can let graphene be more conveniently applied as an advanced plasmonic material.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000336841000007 Publication Date 2014-05-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 9 Open Access
Notes ; This work was supported by the Ministry of Science and Technology of China (Grant No. 2011YQ130018), the Department of Science and Technology of Yunnan Province, the Chinese Academy of Sciences, and by the National Natural Science Foundation of China (Grant No. 11247002). ; Approved Most recent IF: 3.836; 2014 IF: 3.736
Call Number UA @ lucian @ c:irua:117764 Serial 2642
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Author Boënne, W.; Desmet, N.; Van Looy, S.; Seuntjens, P.
Title Use of online water quality monitoring for assessing the effects of WWTP overflows in rivers Type A1 Journal article
Year 2014 Publication Environmental science : processes & impacts Abbreviated Journal
Volume 16 Issue 6 Pages 1510-1518
Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The effects on river water quality of sewer overflows are not well known. Since the duration of the overflow is in the order of magnitude of minutes to hours, continuous measurements of water quality are needed and traditional grab sampling is unable to quantify the pollution loads. The objective of this paper was to demonstrate the applicability of high frequency measurements for assessing the impacts of waste water treatment plants on the water quality of the receiving surface water. In our in situ water quality monitoring setup, two types of multiparameter sensors mounted on a floating fixed platform were used to determine the dynamics of dissolved oxygen, specific conductivity, ammonium-N, nitrate-N and dissolved organic carbon downstream of a waste water treatment plant (WWTP), in combination with data on rainfall, river discharge and WWTP overflow discharge. The monitoring data for water quantity and water quality were used to estimate the pollution load from waste water overflow events and to assess the impact of waste water overflows on the river water quality. The effect of sewer overflow on a small river in terms of N load was shown to be significant. The WWTP overflow events accounted for about 1/3 of the river discharge. The NH4-N loads during overflow events contributed 29% and 21% to the August 2010 and June 2011 load, respectively, in only 8% and 3% of the monthly time span. The results indicate that continuous monitoring is needed to accurately represent the effects of sewer overflows in river systems.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000336841600031 Publication Date 2014-03-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7887; 2050-7895 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:118390 Serial 8722
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Author Batuk, M.; Batuk, D.; Abakumov, A.M.; Hadermann, J.
Title Pb5Fe3TiO11Cl : a rare example of Ti(IV) in a square pyramidal oxygen coordination Type A1 Journal article
Year 2014 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 215 Issue Pages 245-252
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A new oxychloride Pb5Fe3TiO11Cl has been synthesized using the solid state method. Its crystal and magnetic structure was investigated in the 1.5550 K temperature range using electron diffraction, high angle annular dark field scanning transmission electron microscopy, atomic resolution energy dispersive X-ray spectroscopy, neutron and X-ray powder diffraction. At room temperature Pb5Fe3TiO11Cl crystallizes in the P4/mmm space group with the unit cell parameters a=3.91803(3) Å and c=19.3345(2) Å. Pb5Fe3TiO11Cl is a new n=4 member of the oxychloride perovskite-based homologous series An+1BnO3n−1Cl. The structure is built of truncated Pb3Fe3TiO11 quadruple perovskite blocks separated by CsCl-type Pb2Cl slabs. The perovskite blocks consist of two layers of (Fe,Ti)O6 octahedra sandwiched between two layers of (Fe,Ti)O5 square pyramids. The Ti4+ cations are preferentially located in the octahedral layers, however, the presence of a noticeable amount of Ti4+ in a five-fold coordination environment has been undoubtedly proven using neutron powder diffraction and atomic resolution compositional mapping. Pb5Fe3TiO11Cl is antiferromagnetically ordered below 450(10) K. The ordered Fe magnetic moments at 1.5 K are 4.06(4) μB and 3.86(5) μB on the octahedral and square-pyramidal sites, respectively.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos (up) 000336891300037 Publication Date 2014-04-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited 4 Open Access
Notes Fwo G.0184.09n. Approved Most recent IF: 2.299; 2014 IF: 2.133
Call Number UA @ lucian @ c:irua:117066 Serial 3551
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Author Çakir, D.; Peeters, F.M.
Title Dependence of the electronic and transport properties of metal-MoSe2 interfaces on contact structures Type A1 Journal article
Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 89 Issue 24 Pages 245403
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Transition metal dichalcogenides (TMDs) are considered as promising candidates for next generation of electronic and optoelectronic devices. To make use of these materials, for instance in field effect transistor applications, it is mandatory to know the detailed properties of contacts of such TMDs with metal electrodes. Here, we investigate the role of the contact structure on the electronic and transport properties of metal-MoSe2 interfaces. Two different contact types, namely face and edge contacts, are studied. We consider both low (Sc) and high (Au) work function metals in order to thoroughly elucidate the role of the metal work function and the type of metal. First principles plane wave calculations and transport calculations based on nonequilibrium Green's function formalism reveal that the contact type has a large impact on the electronic and transport properties of metal-MoSe2 interfaces. For the Sc electrode, the Schottky barrier heights are around 0.25 eV for face contact and bigger than 0.6 eV for edge contact. For the Au case, we calculate very similar barrier heights for both contact types with an average value of 0.5 eV. Furthermore, while the face contact is found to be highly advantageous as compared to the edge contact for the Sc electrode, the latter contact becomes a better choice for the Au electrode. Our findings provide guidelines for the fabrication of TMD-based devices.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000336917700004 Publication Date 2014-06-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 39 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. D. C. is supported by a FWO Pegasus-short Marie Curie Fellowship. ; Approved Most recent IF: 3.836; 2014 IF: 3.736
Call Number UA @ lucian @ c:irua:117750 Serial 644
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Author Smets, Q.; Verreck, D.; Verhulst, A.S.; Rooyackers, R.; Merckling, C.; Van De Put, M.; Simoen, E.; Vandervorst, W.; Collaert, N.; Thean, V.Y.; Sorée, B.; Groeseneken, G.; Heyns, M.M.;
Title InGaAs tunnel diodes for the calibration of semi-classical and quantum mechanical band-to-band tunneling models Type A1 Journal article
Year 2014 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 115 Issue 18 Pages 184503-184509
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Promising predictions are made for III-V tunnel-field-effect transistor (FET), but there is still uncertainty on the parameters used in the band-to-band tunneling models. Therefore, two simulators are calibrated in this paper; the first one uses a semi-classical tunneling model based on Kane's formalism, and the second one is a quantum mechanical simulator implemented with an envelope function formalism. The calibration is done for In0.53Ga0.47As using several p+/intrinsic/n+ diodes with different intrinsic region thicknesses. The dopant profile is determined by SIMS and capacitance-voltage measurements. Error bars are used based on statistical and systematic uncertainties in the measurement techniques. The obtained parameters are in close agreement with theoretically predicted values and validate the semi-classical and quantum mechanical models. Finally, the models are applied to predict the input characteristics of In0.53Ga0.47As n- and p-lineTFET, with the n-lineTFET showing competitive performance compared to MOSFET.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos (up) 000336919400048 Publication Date 2014-05-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 34 Open Access
Notes ; Quentin Smets and Devin Verreck gratefully acknowledge the support of a Ph. D. stipend from IWT-Vlaanderen. This work was supported by imec's industrial affiliation program. The authors thank Kim Baumans, Johan Feyaerts, Johan De Cooman, Alireza Alian, and Jos Moonens for their support in process development; Bastien Douhard and Joris Delmotte for SIMS characterization; Alain Moussa for AFM characterization; Joris Van Laer and Tom Daenen for their support in electrical characterization; Kuo-Hsing Kao, Mehbuba Tanzid, and Ali Pourghaderi for their support in modeling. ; Approved Most recent IF: 2.068; 2014 IF: 2.183
Call Number UA @ lucian @ c:irua:118009 Serial 1667
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Author Zhang, Y.; Jiang, W.; Zhang, Q.Z.; Bogaerts, A.
Title Computational study of plasma sustainability in radio frequency micro-discharges Type A1 Journal article
Year 2014 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 115 Issue 19 Pages 193301-193311
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We apply an implicit particle-in-cell Monte-Carlo (PIC-MC) method to study a radio-frequency argon microdischarge at steady state in the glow discharge limit, in which the microdischarge is sustained by secondary electron emission from the electrodes. The plasma density, electron energy distribution function (EEDF), and electron temperature are calculated in a wide range of operating conditions, including driving voltage, microdischarge gap, and pressure. Also, the effect of gap size scaling (in the range of 50-1000 μm) on the plasma sustaining voltage and peak electron density at atmospheric pressure is examined, which has not been explored before. In our simulations, three different EEDFs, i.e., a so-called three temperature hybrid mode, a two temperature α mode, and a two temperature γ mode distribution, are identified at different gaps and voltages. The maximum sustaining voltage to avoid a transition from the glow mode to an arc is predicted, as well as the minimum sustaining voltage for a steady glow discharge. Our calculations elucidate that secondary electrons play an essential role in sustaining the discharge, and as a result the relationship between breakdown voltage and gap spacing is far away from the Paschen law at atmospheric pressure.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos (up) 000336920200010 Publication Date 2014-05-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 11 Open Access
Notes Approved Most recent IF: 2.068; 2014 IF: 2.183
Call Number UA @ lucian @ c:irua:116948 Serial 458
Permanent link to this record
 
 
Author Xiao, Y.M.; Xu, W.; Peeters, F.M.
Title Infrared to terahertz absorption window in mono- and multi-layer graphene systems Type A1 Journal article
Year 2014 Publication Optics communications Abbreviated Journal Opt Commun
Volume 328 Issue Pages 135-142
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present a theoretical study on optical properties such as optical conductance and light transmission coefficient for mono- and multi-layer graphene systems with AB- and ABC-stacking. Considering an air/graphene/dielectric-water structure, the optical coefficients for those graphene systems are examined and compared. The universal optical conductance sigma(N)(0)=N pi e(2)/(2h) for N layer graphene systems in the visible region is verified. For N 3 layer graphene, the mini-gap induced absorption edges can be observed in odd layers AB-stacked multilayer graphene, where the number and position of the absorption edges are decided by the layers number N. Meanwhile, we can observe the optical absorption windows for those graphene systems in the infrared to terahertz bandwidth (0.2-150 THz). The absorption window is induced by different transition energies required for inter- and intra-band optical absorption channels. We find that the depth and width of the absorption window can be tuned not only via varying temperature and electron density but also by changing the number of graphene layers and the stacking order. These theoretical findings demonstrate that mono- and multi-layer graphene systems can be applied as frequency tunable optoelectronic devices working in infrared to terahertz bandwidth. (C) 2014 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos (up) 000336970000022 Publication Date 2014-05-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0030-4018; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.588 Times cited 7 Open Access
Notes ; This work was supported by the Ministry of Science and Technology of China (Grant no, 2011YQ130018), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. ; Approved Most recent IF: 1.588; 2014 IF: 1.449
Call Number UA @ lucian @ c:irua:118364 Serial 1666
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Author Croitoru, M.D.; Buzdin, A.I.
Title Peculiarities of the orbital effect in the Fulde-Ferrell-Larkin-Ovchinnikov state in quasi-one-dimensional superconductors Type A1 Journal article
Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 89 Issue 22 Pages 224506
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using the quasiclassical formalism, we determine the low-temperature phase diagram of a quasi-one-dimensional superconductor, taking into account the interchain Josephson coupling and the paramagnetic spin splitting. We show that the anisotropy of the onset of superconductivity changes in the FFLO state as compared with the conventional superconducting phase. It can result in anomalous peaks in the field-direction dependence of the upper critical field when the magnetic field length equals to the FFLO period. This regime is characterized by the lock-in effect of the FFLO modulation wave vector, which is governed by the magnetic length. Furthermore, in the FFLO phase, the anisotropy of the upper critical field is inverted at T-1(**) = 0.5T(c0), where the orbital anisotropy disappears. We suggest that an experimental study of the anisotropy of the upper critical field can provide very reach information about the parameters of the FFLO phase in quasi-1D samples.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos (up) 000336975000005 Publication Date 2014-06-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited Open Access
Notes Approved Most recent IF: 3.836; 2014 IF: 3.736
Call Number UA @ lucian @ c:irua:117749 Serial 2569
Permanent link to this record
 
 
Author Gorlé, C.; Larsson, J.; Emory, M.; Iaccarino, G.
Title The deviation from parallel shear flow as an indicator of linear eddy-viscosity model inaccuracy Type A1 Journal article
Year 2014 Publication Physics of fluids Abbreviated Journal Phys Fluids
Volume 26 Issue 5 Pages 051702
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A marker function designed to indicate in which regions of a generic flow field the results from linear eddy-viscosity turbulence models are plausibly inaccurate is introduced. The marker is defined to identify regions that deviate from parallel shear flow. For two different flow fields it is shown that these regions largely coincide with regions where the prediction of the Reynolds stress divergence is inaccurate. The marker therefore offers a guideline for interpreting results obtained from Reynolds-averaged Navier-Stokes simulations and provides a basis for the further development of turbulence model-form uncertainty quantification methods. (C) 2014 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher Place of Publication Woodbury, N.Y. Editor
Language Wos (up) 000337103900002 Publication Date 2014-05-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1070-6631;1089-7666; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.232 Times cited 19 Open Access
Notes Approved Most recent IF: 2.232; 2014 IF: 2.031
Call Number UA @ lucian @ c:irua:118385 Serial 684
Permanent link to this record
 
 
Author Çakir, D.; Peeters, F.M.; Sevik, C.
Title Mechanical and thermal properties of h-MX2 (M = Cr, Mo, W; X = O, S, Se, Te) monolayers : a comparative study Type A1 Journal article
Year 2014 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 104 Issue 20 Pages 203110
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using density functional theory, we obtain the mechanical and thermal properties of MX2 monolayers (where M = Cr, Mo, W and X = O, S, Se, Te). The C-centered phonon frequencies (i.e., A(1), A(2)'', E ', and E ''), relative frequency values of A(1), and E ' modes, and mechanical properties (i.e., elastic constants, Young modulus, and Poisson's ratio) display a strong dependence on the type of metal and chalcogenide atoms. In each chalcogenide (metal) group, transition-metal dichalcogenides (TMDCs) with W (O) atom are found to be much stiffer. Consistent with their stability, the thermal expansion of lattice constants for TMDCs with O (Te) is much slower (faster). Furthermore, in a heterostructure of these materials, the difference of the thermal expansion of lattice constants between the individual components becomes quite tiny over the whole temperature range. The calculated mechanical and thermal properties show that TMDCs are promising materials for heterostructures. (C) 2014 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos (up) 000337140800063 Publication Date 2014-05-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951;1077-3118; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 130 Open Access
Notes ; Cem Sevik acknowledges the support from Scientific and Technological Research Council of Turkey (TUBITAK-113F096) and Anadolu University (BAP-1306F261 and -1306F281) to this project. We would also like to thank the ULAKBIM High Performance and Grid Computing Center for a generous time allocation for our projects. D. C. was supported by a FWO Pegasus-short Marie Curie Fellowship. Part of this work was supported by the Methusalem foundation of the Flemish Government. ; Approved Most recent IF: 3.411; 2014 IF: 3.302
Call Number UA @ lucian @ c:irua:118379 Serial 1974
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Author Shakouri, K.; Vasilopoulos, P.; Vargiamidis, V.; Hai, G.-Q.; Peeters, F.M.
Title Spin- and valley-dependent commensurability oscillations and electric-field-induced quantum Hall plateaux in periodically modulated silicene Type A1 Journal article
Year 2014 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 104 Issue 21 Pages 213109
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the commensurability oscillations in silicene subject to a perpendicular electric field E-z, a weak magnetic field B, and a weak periodic potential V = V-0 cos(Cy); C = 2 pi/a(0) with a(0) its period. The field E-z and/or the modulation lift the spin degeneracy of the Landau levels and lead to spin and valley resolved Weiss oscillations. The spin resolution is maximal when the field E-z is replaced by a periodic one E-z = E-0 cos(Dy); D = 2 pi/b(0), while the valley one is maximal for b(0) = a(0). In certain ranges of B values, the current is fully spin or valley polarized. Additional quantum Hall conductivity plateaux arise due to spin and valley intra-Landau-level transitions. (C) 2014 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos (up) 000337143000047 Publication Date 2014-05-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951;1077-3118; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 16 Open Access
Notes ; The work was supported by the Flemish Science Foundation (FWO-VI), the Methusalem Foundation of the Flemish Government, and by the Canadian NSERC Grant No. OGP0121756. Also, G. Q. H. was supported by FAPESP and CNPq (Brazil). ; Approved Most recent IF: 3.411; 2014 IF: 3.302
Call Number UA @ lucian @ c:irua:118409 Serial 3078
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Author Huang, S.-Z.; Jin, J.; Cai, Y.; Li, Y.; Tan, H.-Y.; Wang, H.-E.; Van Tendeloo, G.; Su, B.-L.
Title Engineering single crystalline Mn3O4 nano-octahedra with exposed highly active {011} facets for high performance lithium ion batteries Type A1 Journal article
Year 2014 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 6 Issue 12 Pages 6819-6827
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Well shaped single crystalline Mn3O4 nano-octahedra with exposed highly active {011} facets at different particle sizes have been synthesized and used as anode materials for lithium ion batteries. The electrochemical results show that the smallest sized Mn3O4 nano-octahedra show the best cycling performance with a high initial charge capacity of 907 mA h g−1 and a 50th charge capacity of 500 mA h g−1 at a current density of 50 mA g−1 and the best rate capability with a charge capacity of 350 mA h g−1 when cycled at 500 mA g−1. In particular, the nano-octahedra samples demonstrate a much better electrochemical performance in comparison with irregular shaped Mn3O4 nanoparticles. The best electrochemical properties of the smallest Mn3O4 nano-octahedra are ascribed to the lower charge transfer resistance due to the exposed highly active {011} facets, which can facilitate the conversion reaction of Mn3O4 and Li owing to the alternating Mn and O atom layers, resulting in easy formation and decomposition of the amorphous Li2O and the multi-electron reaction. On the other hand, the best electrochemical properties of the smallest Mn3O4 nano-octahedra can also be attributed to the smallest size resulting in the highest specific surface area, which provides maximum contact with the electrolyte and facilitates the rapid Li-ion diffusion at the electrode/electrolyte interface and fast lithium-ion transportation within the particles. The synergy of the exposed {011} facets and the smallest size (and/or the highest surface area) led to the best performance for the Mn3O4 nano-octahedra. Furthermore, HRTEM observations verify the oxidation of MnO to Mn3O4 during the charging process and confirm that the Mn3O4 octahedral structure can still be partly maintained after 50 dischargecharge cycles. The high Li-ion storage capacity and excellent cycling performance suggest that Mn3O4 nano-octahedra with exposed highly active {011} facets could be excellent anode materials for high-performance lithium-ion batteries.
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Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos (up) 000337143900072 Publication Date 2014-04-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2040-3364;2040-3372; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 7.367 Times cited 80 Open Access
Notes Approved Most recent IF: 7.367; 2014 IF: 7.394
Call Number UA @ lucian @ c:irua:117076 Serial 1047
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