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Author Heyne, M.H.; de Marneffe, J.-F.; Delabie, A.; Caymax, M.; Neyts, E.C.; Radu, I.; Huyghebaert, C.; De Gendt, S.
Title Two-dimensional WS2 nanoribbon deposition by conversion of pre-patterned amorphous silicon Type A1 Journal article
Year 2017 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume (down) 28 Issue 28 Pages 04LT01
Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We present a method for area selective deposition of 2D WS2 nanoribbons with tunable thickness on a dielectric substrate. The process is based on a complete conversion of a prepatterned, H-terminated Si layer to metallic W by WF6, followed by in situ sulfidation by H2S. The reaction process, performed at 450 degrees C, yields nanoribbons with lateral dimension down to 20 nm and with random basal plane orientation. The thickness of the nanoribbons is accurately controlled by the thickness of the pre-deposited Si layer. Upon rapid thermal annealing at 900 degrees C under inert gas, the WS2 basal planes align parallel to the substrate.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000391445100001 Publication Date 2016-12-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 13 Open Access OpenAccess
Notes Approved Most recent IF: 3.44
Call Number UA @ lucian @ c:irua:140382 Serial 4471
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Author Petrovic, M.D.; Milovanović, S.P.; Peeters, F.M.
Title Scanning gate microscopy of magnetic focusing in graphene devices : quantum versus classical simulation Type A1 Journal article
Year 2017 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume (down) 28 Issue 28 Pages 185202
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We compare classical versus quantum electron transport in recently investigated magnetic focusing devices (Bhandari et al 2016 Nano Lett. 16 1690) exposed to the perturbing potential of a scanning gate microscope (SGM). Using the Landauer-Buttiker formalism for a multi-terminal device, we calculate resistance maps that are obtained as the SGM tip is scanned over the sample. There are three unique regimes in which the scanning tip can operate (focusing, repelling, and mixed regime) which are investigated. Tip interacts mostly with electrons with cyclotron trajectories passing directly underneath it, leaving a trail of modified current density behind it. Other (indirect) trajectories become relevant when the tip is placed near the edges of the sample, and current is scattered between the tip and the edge. We point out that, in contrast to SGM experiments on gapped semiconductors, the STM tip can induce a pn junction in graphene, which improves contrast and resolution in SGM. We also discuss possible explanations for spatial asymmetry of experimentally measured resistance maps, and connect it with specific configurations of the measuring probes.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000399273800001 Publication Date 2017-03-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 7 Open Access
Notes ; This work was supported by the Methusalem program of the Flemish government. ; Approved Most recent IF: 3.44
Call Number UA @ lucian @ c:irua:143639 Serial 4607
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Author Li, L.L.; Moldovan, D.; Xu, W.; Peeters, F.M.
Title Electric-and magnetic-field dependence of the electronic and optical properties of phosphorene quantum dots Type A1 Journal article
Year 2017 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume (down) 28 Issue 8 Pages 085702
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Recently, black phosphorus quantum dots were fabricated experimentally. Motivated by these experiments, we theoretically investigate the electronic and optical properties of rectangular phosphorene quantum dots (RPQDs) in the presence of an in-plane electric field and a perpendicular magnetic field. The energy spectra and wave functions of RPQDs are obtained numerically using the tight-binding approach. We find edge states within the band gap of the RPQD which are well separated from the bulk states. In an undoped RPQD and for in-plane polarized light, due to the presence of well-defined edge states, we find three types of optical transitions which are between the bulk states, between the edge and bulk states, and between the edge states. The electric and magnetic fields influence the bulk-to-bulk, edge-to-bulk, and edge-to- edge transitions differently due to the different responses of bulk and edge states to these fields.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000403100700001 Publication Date 2017-01-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 32 Open Access
Notes ; This work was financially supported by the China Scholarship Council (CSC), the Flemish Science Foundation (FWO-Vl), the National Natural Science Foundation of China (Grant Nos. 11304316 and 11574319), and by the Chinese Academy of Sciences (CAS). ; Approved Most recent IF: 3.44
Call Number UA @ lucian @ c:irua:144325 Serial 4648
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Author Singh, V.; Mehta, B.R.; Sengar, S.K.; Karakulina, O.M.; Hadermann, J.; Kaushal, A.
Title Achieving independent control of core diameter and carbon shell thickness in Pd-C core–shell nanoparticles by gas phase synthesis Type A1 Journal article
Year 2017 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume (down) 28 Issue 29 Pages 295603
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Pd-C core–shell nanoparticles with independently controllable core size and shell thickness are grown by gas phase synthesis. First, the core size is selected by electrical mobility values of charged particles, and second, the shell thickness is controlled by the concentration of carbon precursor gas. The carbon shell grows by adsorption of carbon precursor gas molecules on the surface of nanoparticles, followed by sintering. The presence of a carbon shell on Pd nanoparticles is potentially important in hydrogen-related applications operating at high temperatures or in catalytic reactions in acidic/aqueous environments.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000404633200002 Publication Date 2017-06-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 1 Open Access Not_Open_Access
Notes VS is thankful to the All India Council for Technical Education, India, for providing assistantship under its Quality Improvement Programme. BRM gratefully acknowledges the support of the Nanomission Programme of the Department of Science and Technology (DST), India and Schlumberger Chair Professorship. BRM would also like to acknowledge the support from the project funded by BRNS, DAE, India. Approved Most recent IF: 3.44
Call Number EMAT @ emat @c:irua:144831 Serial 4712
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Author Wang, L.; Wen, D.-Q.; Zhang, Q.-Z.; Song, Y.-H.; Zhang, Y.-R.; Wang, Y.-N.
Title Disruption of self-organized striated structure induced by secondary electron emission in capacitive oxygen discharges Type A1 Journal article
Year 2019 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume (down) 28 Issue 5 Pages 055007
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Self-organized striated structure has been observed experimentally and numerically in CF4 plasmas in radio-frequency capacitively coupled plasmas recently (Liu et al 2016 Phys. Rev. Lett. 116 255002). In this work, the striated structure is investigated in a capacitively coupled oxygen discharge with the introduction of the effect from the secondary electron emission, based on a particle-in-cell/Monte Carlo collision model. As we know, the transport of positive and negative ions plays a key role in the formation of striations in electronegative gases, for which, the electronegativity needs to be large enough. As the secondary electron emission increases, electrons in the sheaths gradually contribute more ionization to the discharge. Meanwhile, the increase of the electron density, especially in the plasma bulk, leads to an increased electrical conductivity and a reduced bulk electric field, which would shield the ions' mobility. These changes result in enlarged striation gaps. And then, with more emitted electrons, obvious disruption of the striations is observed accompanied with a transition of electron heating mode. Due to the weakened field, the impact ionization in the plasma bulk is attenuated, compared with the enhanced ionization caused by secondary electrons. This would lead to the electron heating mode transition from striated (STR) mode to gamma-mode. Besides, our investigation further reveals that gamma-mode is more likely to dominate the discharge under high gas pressures or driving voltages.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000467827800001 Publication Date 2019-04-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0963-0252 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 2 Open Access Not_Open_Access: Available from 13.05.2020
Notes Approved Most recent IF: 3.302
Call Number UA @ admin @ c:irua:160365 Serial 5270
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Author Kindratenko, V.V.; van Espen, P.J.M.; Treiger, B.A.; Van Grieken, R.E.
Title Fractal dimensional classification of aerosol particles by computer-controlled scanning electron microscopy Type A1 Journal article
Year 1994 Publication Environmental science and technology Abbreviated Journal
Volume (down) 28 Issue Pages 2197-2202
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Chemometrics (Mitac 3)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1994PP82900033 Publication Date 2007-05-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-936x; 1520-5851 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:9497 Serial 7983
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Author Dubourdieu, C.; Rauwel, E.; Roussel, H.; Ducroquet, F.; Hollaender, B.; Rossell, M.; Van Tendeloo, G.; Lhostis, S.; Rushworth, S.
Title Addition of yttrium into HfO2 films: microstructure and electrical properties Type A1 Journal article
Year 2009 Publication Journal of vacuum science and technology: A: vacuum surfaces and films Abbreviated Journal J Vac Sci Technol A
Volume (down) 27 Issue 3 Pages 503-514
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The cubic phase of HfO2 was stabilized by addition of yttrium in thin films grown on Si/SiO2 by metal-organic chemical vapor deposition. The cubic phase was obtained for contents of 6.5 at. % Y or higher at a temperature as low as 470 °C. The complete compositional range (from 1.5 to 99.5 at. % Y) was investigated. The crystalline structure of HfO2 was determined from x-ray diffraction, electron diffraction, and attenuated total-reflection infrared spectroscopy. For cubic films, the continuous increase in the lattice parameter indicates the formation of a solid-solution HfO2Y2O3. As shown by x-ray photoelectron spectroscopy, yttrium silicate is formed at the interface with silicon; the interfacial layer thickness increases with increasing yttrium content and increasing film thickness. The dependence of the intrinsic relative permittivity r as a function of Y content was determined. It exhibits a maximum of ~30 for ~8.8 at. % Y. The cubic phase is stable upon postdeposition high-temperature annealing at 900 °C under NH3.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000265739100016 Publication Date 2009-05-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0734-2101; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.374 Times cited 29 Open Access
Notes Approved Most recent IF: 1.374; 2009 IF: 1.297
Call Number UA @ lucian @ c:irua:77054 Serial 58
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Author Kolev, I.; Bogaerts, A.
Title Numerical study of the sputtering in a dc magnetron Type A1 Journal article
Year 2009 Publication Journal of vacuum science and technology: A: vacuum surfaces and films Abbreviated Journal J Phys Chem C
Volume (down) 27 Issue 1 Pages 20-28
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Molecular dynamics simulations were used to investigate the size-dependent melting mechanism of nickel nanoclusters of various sizes. The melting process was monitored by the caloric curve, the overall cluster Lindemann index, and the atomic Lindemann index. Size-dependent melting temperatures were determined, and the correct linear dependence on inverse diameter was recovered. We found that the melting mechanism gradually changes from dynamic coexistence melting to surface melting with increasing cluster size. These findings are of importance in better understanding carbon nanotube growth by catalytic chemical vapor deposition as the phase state of the catalyst nanoparticle codetermines the growth mechanism.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000263299600018 Publication Date 2009-02-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.536 Times cited 66 Open Access
Notes Approved Most recent IF: 4.536; 2009 IF: 4.224
Call Number UA @ lucian @ c:irua:71634 Serial 2411
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Author Wang, H.; Picot, T.; Houben, K.; Moorkens, T.; Grigg, J.; Van Haesendonck, C.; Biermans, E.; Bals, S.; Brown, S.A.; Vantomme, A.; Temst, K.; Van Bael, M.J.;
Title The superconducting proximity effect in epitaxial Al/Pb nanocomposites Type A1 Journal article
Year 2014 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume (down) 27 Issue 1 Pages 015008-8
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We have investigated the superconducting properties of Pb nanoparticles with a diameter ranging from 8 to 20 nm, synthesized by Pb+ ion implantation in a crystalline Al matrix. A detailed structural characterization of the nanocomposites reveals the highly epitaxial relation between the Al crystalline matrix and the Pb nanoparticles. The Al/Pb nanocomposites display a single superconducting transition, with the critical temperature T-c increasing with the Pb content. The dependence of T-c on the Pb/Al volume ratio was compared with theoretical models of the superconducting proximity effect based on the bulk properties of Al and Pb. A very good correspondence with the strong-coupling proximity effect model was found, with an electron-phonon coupling constant in the Pb nanoparticles slightly reduced compared to bulk Pb. Our result differs from other studies on Pb nanoparticle based proximity systems where weak-coupling models were found to better describe the T-c dependence. We infer that the high interface quality resulting from the ion implantation synthesis method is a determining factor for the superconducting properties. Critical field and critical current measurements support the high quality of the nanocomposite superconducting films.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000328275000010 Publication Date 2013-11-28
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 2 Open Access Not_Open_Access
Notes ; This work was supported by the Research Foundation-Flanders (FWO), the KU Leuven BOF Concerted Research Action programs (GOA/09/006, the KU Leuven BOF CREA/12/015 project, and GOA/14/007) and the EU FP7 program SPIRIT (227012). TP and KH are postdoctoral research fellow and doctoral fellow of the FWO. ; Approved Most recent IF: 2.878; 2014 IF: 2.325
Call Number UA @ lucian @ c:irua:112833 Serial 3599
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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 (down) 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 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 Milovanovic, S.P.; Peeters, F.M.
Title Characterization of the size and position of electron-hole puddles at a graphene p-n junction Type A1 Journal article
Year 2016 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume (down) 27 Issue 27 Pages 105203
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The effect of an electron-hole puddle on the electrical transport when governed by snake states in a bipolar graphene structure is investigated. Using numerical simulations we show that information on the size and position of the electron-hole puddle can be obtained using the dependence of the conductance on magnetic field and electron density of the gated region. The presence of the scatterer disrupts snake state transport which alters the conduction pattern. We obtain a simple analytical formula that connects the position of the electron-hole puddle with features observed in the conductance. The size of the electron-hole puddle is estimated from the magnetic field and gate potential that maximizes the effect of the puddle on the electrical transport.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000369849200003 Publication Date 2016-02-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 3 Open Access
Notes This work was supported by the Flemish Science Foundation (FWO-Vl) and the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN. We acknowledge interesting correspondence with Thiti Taychatanapat. Approved Most recent IF: 3.44
Call Number c:irua:131907 Serial 4025
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Author Spadaro, M.C.; Luches, P.; Bertoni, G.; Grillo, V.; Turner, S.; Van Tendeloo, G.; Valeri, S.; D'Addato, S.
Title Influence of defect distribution on the reducibility of CeO2-x nanoparticles Type A1 Journal article
Year 2016 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume (down) 27 Issue 27 Pages 425705
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Ceria nanoparticles (NPs) are fundamental in heterogeneous catalysis because of their ability to store or release oxygen depending on the ambient conditions. Their oxygen storage capacity is strictly related to the exposed planes, crystallinity, density and distribution of defects. In this work a study of ceria NPs produced with a ligand-free, physical synthesis method is presented. The NP films were grown by a magnetron sputtering based gas aggregation source and studied by high resolution- and scanning-transmission electron microscopy and x-ray photoelectron spectroscopy. In particular, the influence of the oxidation procedure on the NP reducibility has been investigated. The different reducibility has been correlated to the exposed planes, crystallinity and density and distribution of structural defects. The results obtained in this work represent a basis to obtain cerium oxide NP with desired oxygen transport properties.
Address Dipartimento FIM, Universita di Modena e Reggio Emilia, via G. Campi 213/a, I-41125 Modena, Italy. CNR-NANO, via G. Campi 213/a, I-41125 Modena, Italy
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000385483900004 Publication Date 2016-09-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 11 Open Access
Notes The authors gratefully acknowledge financial support by the Italian MIUR under grant FIRB RBAP115AYN (Oxides at the nanoscale: multifunctionality and applications). The activity is performed within the COST Action CM1104 'Reducible oxide chemistry, structure and functions'. The research leading to these results has received funding also from the European Union Seventh Framework Programme under Grant Agreement 312483—ESTEEM2 (Integrated Infrastructure Initiative–I3).; esteem2_ta Approved Most recent IF: 3.44
Call Number EMAT @ emat @ c:irua:135424 Serial 4130
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Author Cai, H.; Kang, J.; Sahin, H.; Chen, B.; Suslu, A.; Wu, K.; Peeters, F.; Meng, X.; Tongay, S.
Title Exciton pumping across type-I gallium chalcogenide heterojunctions Type A1 Journal article
Year 2016 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume (down) 27 Issue 27 Pages 065203
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Quasi-two-dimensional gallium chalcogenide heterostructures are created by transferring exfoliated few-layer GaSe onto bulk GaTe sheets. Luminescence spectroscopy measurements reveal that the light emission from underlying GaTe layers drastically increases on heterojunction regions where GaSe layers make contact with the GaTe. Density functional theory (DFT) and band offset calculations show that conduction band minimum (CBM) (valance band maximum (VBM)) values of GaSe are higher (lower) in energy compared to GaTe, forming type-I band alignment at the interface. Consequently, GaSe layers provide photo-excited electrons and holes to GaTe sheets through relatively large built-in potential at the interface, increasing overall exciton population and light emission from GaTe. Observed results are not specific to the GaSe/GaTe system but observed on GaS/GaSe heterolayers with type-I band alignment. Observed experimental findings and theoretical studies provide unique insights into interface effects across dissimilar gallium chalcogenides and offer new ways to boost optical performance by simple epitaxial coating.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000368897100008 Publication Date 2016-01-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 15 Open Access
Notes ; This work was supported by the Arizona State University seeding program, the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus-short Marie Curie Fellowship. We acknowledge the use of the John M Cowley Center for High Resolution Electron Microscopy at Arizona State University. The authors thank Anupum Pant for useful discussions. We gratefully acknowledge the use of the facilities at the LeRoy Eyring Center for Solid State Science at Arizona State University. S Tongay acknowledges support from DMR-1552220. ; Approved Most recent IF: 3.44
Call Number UA @ lucian @ c:irua:131570 Serial 4179
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Author Kiymaz, D.; Yagmurcukardes, M.; Tomak, A.; Sahin, H.; Senger, R.T.; Peeters, F.M.; Zareie, H.M.; Zafer, C.
Title Controlled growth mechanism of poly (3-hexylthiophene) nanowires Type A1 Journal article
Year 2016 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume (down) 27 Issue 27 Pages 455604
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Synthesis of 1D-polymer nanowires by a self-assembly method using marginal solvents is an attractive technique. While the formation mechanism is poorly understood, this method is essential in order to control the growth of nanowires. Here we visualized the time-dependent assembly of poly (3-hexyl-thiophene-2,5-diyl) (P3HT) nanowires by atomic force microscopy and scanning tunneling microscopy. The assembly of P3HT nanowires was carried out at room temperature by mixing cyclohexanone (CHN), as a poor solvent, with polymer solution in 1,2-dichlorobenzene (DCB). Both pi-pi stacking and planarization, obtained at the mix volume ratio of P3HT (in DCB):CHN (10:7), were considered during the investigation. We find that the length of nanowires was determined by the ordering of polymers in the polymer repetition direction. Additionally, our density functional theory calculations revealed that the presence of DCB and CHN molecules that stabilize the structural distortions due to tail group of polymers was essential for the core-wire formation.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000386132600003 Publication Date 2016-10-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 24 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, the High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules Foundation. HS is supported by a FWO Pegasus-Long Marie Curie Fellowship. HS and RTS acknowledge support from TUBITAK through Project No. 114F397. Also, DA is supported by the Scientific Research Project Fund of Ege University (Project Nr: 12GEE011). ; Approved Most recent IF: 3.44
Call Number UA @ lucian @ c:irua:138159 Serial 4350
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Author Tomak, A.; Bacaksiz, C.; Mendirek, G.; Sahin, H.; Hur, D.; Gorgun, K.; Senger, R.T.; Birer, O.; Peeters, F.M.; Zareie, H.M.
Title Structural changes in a Schiff base molecular assembly initiated by scanning tunneling microscopy tip Type A1 Journal article
Year 2016 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume (down) 27 Issue 27 Pages 335601
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We report the controlled self-organization and switching of newly designed Schiff base (E)-4-((4-(phenylethynyl) benzylidene) amino) benzenethiol (EPBB) molecules on a Au (111) surface at room temperature. Scanning tunneling microscopy and spectroscopy (STM/STS) were used to image and analyze the conformational changes of the EPBB molecules. The conformational change of the molecules was induced by using the STM tip while increasing the tunneling current. The switching of a domain or island of molecules was shown to be induced by the STM tip during scanning. Unambiguous fingerprints of the switching mechanism were observed via STM/STS measurements. Surface-enhanced Raman scattering was employed, to control and identify quantitatively the switching mechanism of molecules in a monolayer. Density functional theory calculations were also performed in order to understand the microscopic details of the switching mechanism. These calculations revealed that the molecular switching behavior stemmed from the strong interaction of the EPBB molecules with the STM tip. Our approach to controlling intermolecular mechanics provides a path towards the bottom-up assembly of more sophisticated molecular machines.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000383780500012 Publication Date 2016-07-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 2 Open Access
Notes ; The authors acknowledge financial support from TUBITAK (PROJECT NO: 112T507). This work was also supported by the Flemish Science Foundation (FWO-Vl). Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid-Infrastructure). HS is supported by an FWO Pegasus Long Marie Curie Fellowship. ; Approved Most recent IF: 3.44
Call Number UA @ lucian @ c:irua:137155 Serial 4363
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Author Alves, L.L.; Bogaerts, A.; Guerra, V.; Turner, M.M.
Title Foundations of modelling of nonequilibrium low-temperature plasmas Type A1 Journal article
Year 2018 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume (down) 27 Issue 2 Pages 023002
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract This work explains the need for plasma models, introduces arguments for choosing the type of model that better fits the purpose of each study, and presents the basics of the most common nonequilibrium low-temperature plasma models and the information available from each one, along with an extensive list of references for complementary in-depth reading. The paper presents the following models, organised according to the level of multi-dimensional description of the plasma: kinetic models, based on either a statistical particle-in-cell/Monte-Carlo approach or the solution to the Boltzmann equation (in the latter case, special focus is given to the description of the electron kinetics); multi-fluid models, based on the solution to the hydrodynamic equations; global (spatially-average) models, based on the solution to the particle and energy rate-balance equations for the main plasma species, usually including a very complete reaction chemistry; mesoscopic models for plasma–surface interaction, adopting either a deterministic approach or a stochastic dynamical Monte-Carlo approach. For each plasma model, the paper puts forward the physics context, introduces the fundamental equations, presents advantages and limitations, also from a numerical perspective, and illustrates its application with some examples. Whenever pertinent, the interconnection between models is also discussed, in view of multi-scale hybrid approaches.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000425688600001 Publication Date 2018-02-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 17 Open Access OpenAccess
Notes The authors would like to thank A Tejero-Del-Caz and A Berthelot for their technical contributions in writing the manuscript. This work was partially funded by Portuguese FCT —Fundação para a Ciência e a Tecnologia, under projects UID/ FIS/50010/2013, PTDC/FISPLA/1243/2014 (KIT-PLAS- MEBA) and PTDC/FIS-PLA/1420/2014 (PREMiERE). Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:149391 Serial 4810
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Author Bal, K.M.; Huygh, S.; Bogaerts, A.; Neyts, E.C.
Title Effect of plasma-induced surface charging on catalytic processes: application to CO2activation Type A1 Journal article
Year 2018 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume (down) 27 Issue 2 Pages 024001
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Understanding the nature and effect of the multitude of plasma–surface interactions in plasma catalysis is a crucial requirement for further process development and improvement. A particularly intriguing and rather unique property of a plasma-catalytic setup is the ability of the plasma to modify the electronic structure, and hence chemical properties, of the catalyst through charging, i.e. the absorption of excess electrons. In this work, we develop a quantum chemical model based on density functional theory to study excess negative surface charges in a heterogeneous catalyst exposed to a plasma. This method is specifically applied to investigate plasma-catalytic CO2 activation on supported M/Al2O3 (M=Ti, Ni, Cu) single atom catalysts. We find that (1) the presence of a negative surface charge dramatically improves the reductive power of the catalyst, strongly promoting the splitting of CO2 to CO and oxygen, and (2) the relative activity of the investigated transition metals is also changed upon charging, suggesting that controlled surface charging is a powerful additional parameter to tune catalyst activity and selectivity. These results strongly point to plasma-induced surface charging of the catalyst as an important factor contributing to the plasma-catalyst synergistic effects frequently reported for plasma catalysis.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000424520100001 Publication Date 2018-02-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 19 Open Access OpenAccess
Notes KMB is funded as PhD fellow (aspirant) of the FWO-Flanders (Research Foundation—Flanders), Grant 11V8915N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government— department EWI. Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:149285 Serial 4813
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Author Zhang, Q.-Z.; Bogaerts, A.
Title Propagation of a plasma streamer in catalyst pores Type A1 Journal article
Year 2018 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume (down) 27 Issue 3 Pages 035009
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Although plasma catalysis is gaining increasing interest for various environmental applications, the underlying mechanisms are still far from understood. For instance, it is not yet clear whether and how plasma streamers can propagate in catalyst pores, and what is the minimum pore size to make this happen. As this is crucial information to ensure good plasma-catalyst interaction, we study here the mechanism of plasma streamer propagation in a catalyst pore, by means of a twodimensional particle-in-cell/Monte Carlo collision model, for various pore diameters in the nm range to μm-range. The so-called Debye length is an important criterion for plasma penetration into catalyst pores, i.e. a plasma streamer can penetrate into pores when their diameter is larger than the Debye length. The Debye length is typically in the order of a few 100 nm up to 1 μm at the conditions under study, depending on electron density and temperature in the plasma streamer. For pores in the range of ∼50 nm, plasma can thus only penetrate to some extent and at

very short times, i.e. at the beginning of a micro-discharge, before the actual plasma streamer reaches the catalyst surface and a sheath is formed in front of the surface. We can make plasma streamers penetrate into smaller pores (down to ca. 500 nm at the conditions under study) by increasing the applied voltage, which yields a higher plasma density, and thus reduces the Debye length. Our simulations also reveal that the plasma streamers induce surface charging of the catalyst pore sidewalls, causing discharge enhancement inside the pore, depending on pore diameter and depth.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000427976800001 Publication Date 2018-03-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 16 Open Access OpenAccess
Notes We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604) and from the Fund for Scientific Research Flanders (FWO) (Excellence of Science Program; EOS ID 30505023). This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp. Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:150877 Serial 4954
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Author Zhang, Q.-Z.; Wang, W.-Z.; Bogaerts, A.
Title Importance of surface charging during plasma streamer propagation in catalyst pores Type A1 Journal article
Year 2018 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume (down) 27 Issue 6 Pages 065009
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma catalysis is gaining increasing interest, but the underlying mechanisms are far from understood. Different catalyst materials will have different chemical effects, but in addition, they might also have different dielectric constants, which will affect surface charging, and thus the plasma behavior. In this work, we demonstrate that surface charging plays an important role in the streamer propagation and discharge enhancement inside catalyst pores, and in the plasma distribution along the dielectric surface, and this role greatly depends on the dielectric constant of the material. For εr50, surface charging causes the plasma to spread along the dielectric surface and inside the pores, leading to deeper plasma streamer penetration, while for εr>50 or for metallic coatings, the discharge is more localized, due to very weak surface charging. In addition, at εr=50, the significant surface charge density near the pore entrance causes a large potential drop at the sharp pore edges, which induces a strong electric field and results in most pronounced plasma enhancement near the pore entrance.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000436845700002 Publication Date 2018-06-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 13 Open Access OpenAccess
Notes We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604) and from the TOP-BOF project of the University of Antwerp. This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp. Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:152243 Serial 4995
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Author Zhang, Y.-R.; Neyts, E.C.; Bogaerts, A.
Title Enhancement of plasma generation in catalyst pores with different shapes Type A1 Journal article
Year 2018 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume (down) 27 Issue 5 Pages 055008
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Plasma generation inside catalyst pores is of utmost importance for plasma catalysis, as the existence of plasma species inside the pores affects the active surface area of the catalyst available to the plasma species for catalytic reactions. In this paper, the electric field enhancement, and thus the plasma production inside catalyst pores with different pore shapes is studied with a two-dimensional fluid model. The results indicate that the electric field will be significantly enhanced near tip-like structures. In a conical pore with small opening, the strongest electric field appears at the opening and bottom corners of the pore, giving rise to a prominent ionization rate throughout the pore. For a cylindrical pore, the electric field is only enhanced at the bottom corners of the pore, with lower absolute value, and thus the ionization rate inside the pore is only slightly enhanced. Finally, in a conical pore with large opening, the electric field is characterized by a maximum at the bottom of the pore, yielding a similar behavior for the ionization rate. These results demonstrate that the shape of the pore has a significantly influence on the electric field enhancement, and thus modifies the plasma properties.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000432351700002 Publication Date 2018-05-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 11 Open Access OpenAccess
Notes This work was supported by the Fund for Scientific Research Flanders (FWO) (Grant No. G.0217.14N) and the Fundamental Research Funds for the Central Universities (Grant No. DUT17LK52). Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:151546 Serial 4998
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Author Kolev, S.; Bogaerts, A.
Title Three-dimensional modeling of energy transport in a gliding arc discharge in argon Type A1 Journal Article
Year 2018 Publication Plasma Sources Science & Technology Abbreviated Journal Plasma Sources Sci T
Volume (down) 27 Issue 12 Pages 125011
Keywords A1 Journal Article; gliding arc discharge, sliding arc discharge, energy transport, fluid plasma model, atmospheric pressure plasmas; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
Abstract In this work we study energy transport in a gliding arc discharge with two diverging flat

electrodes in argon gas at atmospheric pressure. The discharge is ignited at the shortest electrode

gap and it is pushed downstream by a forced gas flow. The current values considered are

relatively low and therefore a non-equilibrium plasma is produced. We consider two cases, i.e.

with high and low discharge current (28 mA and 2.8mA), and a constant gas flow of 10 lmin −1 ,

with a significant turbulent component to the velocity. The study presents an analysis of the

various energy transport mechanisms responsible for the redistribution of Joule heating to the

plasma species and the moving background gas. The objective of this work is to provide a

general understanding of the role of the different energy transport mechanisms in arc formation

and sustainment, which can be used to improve existing or new discharge designs. The work is

based on a three-dimensional numerical model, combining a fluid plasma model, the shear stress

transport Reynolds averaged Navier–Stokes turbulent gas flow model, and a model for gas

thermal balance. The obtained results show that at higher current the discharge is constricted

within a thin plasma column several hundred kelvin above room temperature, while in the low-

current discharge the combination of intense convective cooling and low Joule heating prevents

discharge contraction and the plasma column evolves to a static non-moving diffusive plasma,

continuously cooled by the flowing gas. As a result, the energy transport in the two cases is

determined by different mechanisms. At higher current and a constricted plasma column, the

plasma column is cooled mainly by turbulent transport, while at low current and an unconstricted

plasma, the major cooling mechanism is energy transport due to non-turbulent gas convection. In

general, the study also demonstrates the importance of turbulent energy transport in

redistributing the Joule heating in the arc and its significant role in arc cooling and the formation

of the gas temperature profile. In general, the turbulent energy transport lowers the average gas

temperature in the arc, thus allowing additional control of thermal non-equilibrium in the

discharge.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000454555600005 Publication Date 2018-12-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited Open Access Not_Open_Access
Notes This work was supported by the European Regional Devel- opment Fund within the Operational Programme ’Science and Education for Smart Growth 2014 – 2020’ under the Project CoE ’National center of mechatronics and clean technologies’ BG05M2OP001-1.001-0008-C01, and by the Flemish Fund for Scientific Research (FWO); grant no G.0383.16N. Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:155973 Serial 5140
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Author Zhang, Q.-Z.; Bogaerts, A.
Title Capacitive electrical asymmetry effect in an inductively coupled plasma reactor Type A1 Journal Article
Year 2018 Publication Plasma Sources Science & Technology Abbreviated Journal Plasma Sources Sci T
Volume (down) 27 Issue 10 Pages 105019
Keywords A1 Journal Article; electrical asymmetry effect, inductively coupled plasma, self-bias, independent control of the ion fluxes and ion energy; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
Abstract The electrical asymmetry effect is realized by applying multiple frequency power sources

(13.56 MHz and 27.12 MHz) to a capacitively biased substrate electrode in a specific inductively

coupled plasma reactor. On the one hand, by adjusting the phase angle θ between the multiple

frequency power sources, an almost linear self-bias develops on the substrate electrode, and

consequently the ion energy can be well modulated, while the ion flux stays constant within a

large range of θ. On the other hand, the plasma density and ion flux can be significantly

modulated by tuning the inductive power supply, while only inducing a small change in the self-

bias. Independent control of self-bias/ion energy and ion flux can thus be realized in this specific

inductively coupled plasma reactor.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000448434100001 Publication Date 2018-10-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 1 Open Access Not_Open_Access
Notes We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604). This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp. Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:155506 Serial 5069
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Author Zhang, Q.-Z.; Bogaerts, A.
Title Plasma streamer propagation in structured catalysts Type A1 Journal Article
Year 2018 Publication Plasma Sources Science & Technology Abbreviated Journal Plasma Sources Sci T
Volume (down) 27 Issue 10 Pages 105013
Keywords A1 Journal Article; plasma catalysis, streamer propagation, 3D structures, PIC/MCC; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
Abstract Plasma catalysis is gaining increasing interest for various environmental applications. Catalytic

material can be inserted in different shapes in the plasma, e.g., as pellets, (coated) beads, but also

as honeycomb monolith and 3DFD structures, also called ‘structured catalysts’, which have high

mass and heat transfer properties. In this work, we examine the streamer discharge propagation

and the interaction between plasma and catalysts, inside the channels of such structured catalysts,

by means of a two-dimensional particle-in-cell/Monte Carlo collision model. Our results reveal

that plasma streamers behave differently in various structured catalysts. In case of a honeycomb

structure, the streamers are limited to only one channel, with low or high plasma density when

the channels are parallel or perpendicular to the electrodes, respectively. In contrast, in case of a

3DFD structure, the streamers can distribute to different channels, causing discharge

enhancement due to surface charging on the dielectric walls of the structured catalyst, and

especially giving rise to a broader plasma distribution. The latter should be beneficial for plasma

catalysis applications, as it allows a larger catalyst surface area to be exposed to the plasma.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000448131900002 Publication Date 2018-10-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 3 Open Access Not_Open_Access
Notes We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604). This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp. Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @c:irua:155510 Serial 5068
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Author Kapra, A.V.; Misko, V.R.; Peeters, F.M.
Title Controlling magnetic flux motion by arrays of zigzag-arranged magnetic bars Type A1 Journal article
Year 2013 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume (down) 26 Issue 2 Pages 025011-10
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Recent advances in manufacturing arrays of artificial pinning sites, i.e., antidots, blind holes and magnetic dots, allowed an effective control of magnetic flux in superconductors. An array of magnetic bars deposited on top of a superconducting film was shown to display different pinning regimes depending on the direction of the in-plane magnetization of the bars. Changing the sign of their magnetization results in changes in the induced magnetic pinning potentials. By numerically solving the time-dependent Ginzburg-Landau equations in a superconducting film with periodic arrays of zigzag-arranged magnetic bars, we revealed various flux dynamics regimes. In particular, we demonstrate flux pinning and flux flow, depending on the direction of the magnetization of the magnetic bars. Remarkably, the revealed different flux-motion regimes are associated with different mechanisms of vortex-antivortex dynamics. For example, we found that for an 'antiparallel' configuration of magnetic bars this dynamics involves a repeating vortex-antivortex generation and annihilation. We show that the depinning transition and the onset of flux flow can be manipulated by the magnetization of the bars and the geometry of the array. This provides an effective control of the depinning critical current that can be useful for possible fluxonics applications.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000313559300011 Publication Date 2012-12-20
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 5 Open Access
Notes ; We acknowledge useful discussions with Denis Vodolazov and Alejandro Silhanek. This work was supported by the 'Odysseus' Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 2.878; 2013 IF: 2.796
Call Number UA @ lucian @ c:irua:110080 Serial 505
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Author Berdiyorov, G.R.; Savel'ev, S.E.; Kusmartsev, F.V.; Peeters, F.M.
Title In-phase motion of Josephson vortices in stacked SNS Josephson junctions : effect of ordered pinning Type A1 Journal article
Year 2013 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume (down) 26 Issue 12 Pages 125010-125016
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The dynamics of Josephson vortices (fluxons) in artificial stacks of superconducting-normal-superconducting Josephson junctions is investigated using the anisotropic time-dependent Ginzburg-Landau theory in the presence of a square/rectangular array of pinning centers (holes). For small values of the applied drive, fluxons in different junctions move out of phase, forming a periodic triangular lattice. A rectangular lattice of moving fluxons is observed at larger currents, which is in agreement with previous theoretical predictions (Koshelev and Aranson 2000 Phys. Rev. Lett. 85 3938). This 'superradiant' flux-flow state is found to be stable in a wide region of applied current. The stability range of this ordered state is considerably larger than the one obtained for the pinning-free sample. Clear commensurability features are observed in the current-voltage characteristics of the system with pronounced peaks in the critical current at (fractional) matching fields. The effect of density and strength of the pinning centers on the stability of the rectangular fluxon lattice is discussed. Predicted synchronized motion of fluxons in the presence of ordered pinning can be detected experimentally using the rf response of the system, where enhancement of the Shapiro-like steps is expected due to the synchronization.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000327447200013 Publication Date 2013-10-29
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 5 Open Access
Notes ; This work was supported by EU Marie Curie (Project No: 253057) and by the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 2.878; 2013 IF: 2.796
Call Number UA @ lucian @ c:irua:112834 Serial 1573
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Author Molina, L.; Egoavil, R.; Turner, S.; Thersleff, T.; Verbeeck, J.; Holzapfel, B.; Eibl, O.; Van Tendeloo, G.
Title Interlayer structure in YBCO-coated conductors prepared by chemical solution deposition Type A1 Journal article
Year 2013 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume (down) 26 Issue 7 Pages 075016-75018
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The functionality of YBa2Cu3O7−δ (YBCO)-coated conductor technology depends on the reliability and microstructural properties of a given tape or wire architecture. Particularly, the interface to the metal tape is of interest since it determines the adhesion, mechanical stability of the film and thermal contact of the film to the substrate. A trifluoroacetate (TFA)metal organic deposition (MOD) prepared YBCO film deposited on a chemical solution-derived buffer layer architecture based on CeO2/La2Zr2O7 and grown on a flexible Ni5 at.%W substrate with a {100}⟨001⟩ biaxial texture was investigated. The YBCO film had a thickness was 440 nm and a jc of 1.02 MA cm−2 was determined at 77 K and zero external field. We present a sub-nanoscale analysis of a fully processed solution-derived YBCO-coated conductor by aberration-corrected scanning transmission electron microscopy (STEM) combined with electron energy-loss spectroscopy (EELS). For the first time, structural and chemical analysis of the valence has been carried out on the sub-nm scale. Intermixing of Ni, La, Ce, O and Ba takes place at these interfaces and gives rise to nanometer-sized interlayers which are a by-product of the sequential annealing process. Two distinct interfacial regions were analyzed in detail: (i) the YBCO/CeO2/La2Zr2O7 region (10 nm interlayer) and (ii) the La2Zr2O7/Ni5 at.%W substrate interface region (20 nm NiO). This is of particular significance for the functionality of these YBCO-coated conductor architectures grown by chemical solution deposition.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000319973800024 Publication Date 2013-05-28
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 11 Open Access
Notes vortex; Countatoms; Fwo; Esteem2; esteem2jra2; esteem2jra3 ECASJO_; Approved Most recent IF: 2.878; 2013 IF: 2.796
Call Number UA @ lucian @ c:irua:108704UA @ admin @ c:irua:108704 Serial 1698
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Author Gomez, A.; Gonzalez, E.M.; Gilbert, D.A.; Milošević, M.V.; Liu, K.; Vicent, J.L.
Title Probing the dynamic response of antivortex, interstitial and trapped vortex lattices on magnetic periodic pinning potentials Type A1 Journal article
Year 2013 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume (down) 26 Issue 8 Pages 085018-8
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The dynamics of the pinned vortex, antivortex and interstitial vortex have been studied in superconducting/magnetic hybrids consisting of arrays of Co/Pd multilayer nanodots embedded in Nb films. The magnetic nanodots show out-of-plane magnetization at the remanent state. This magnetic state allows for superconducting vortex lattices of different types in an applied homogeneous magnetic field. We experimentally and theoretically show three such lattices: (i) a lattice containing only antivortices; (ii) a vortex lattice entirely pinned on the dots; and (iii) a vortex lattice with pinned and interstitial vortices. Between the flux creep (low vortex velocity) and the free flux flow (high vortex velocity) regimes the interaction between the magnetic array and the vortex lattice governs the vortex dynamics, which in turn enables distinguishing experimentally the type of vortex lattice which governs the dissipation. We show that the vortex lattice with interstitial vortices has the highest onset velocity where the lattice becomes ordered, whereas the pinned vortex lattice has the smallest onset velocity. Further, for this system, we directly estimate that the external force needed to depin vortices is 60% larger than the one needed to depin antivortices; therefore we are able to decouple the antivortex-vortex motion.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000321709400024 Publication Date 2013-07-02
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 was supported by Spanish MINECO, grants FIS2008-06249 (Grupo Consolidado), Consolider CSD2007-00010 and CAM grant S2009/MAT-1726. MVM acknowledges support from FWO-Vlaanderen. Work at UCD was supported by the US NSF (DMR-1008791 and ECCS-0925626). ; Approved Most recent IF: 2.878; 2013 IF: 2.796
Call Number UA @ lucian @ c:irua:109785 Serial 2716
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Author Scuracchio, P.; Dobry, A.; Costamagna, S.; Peeters, F.M.
Title Tuning the polarized quantum phonon transmission in graphene nanoribbons Type A1 Journal article
Year 2015 Publication Nanotechnology Abbreviated Journal Nanotechnology
Volume (down) 26 Issue 26 Pages 305401
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We propose systems that allow a tuning of the phonon transmission function T(omega) in graphene nanoribbons by using C-13 isotope barriers, antidot structures, and distinct boundary conditions. Phonon modes are obtained by an interatomic fifth-nearest neighbor force-constant model (5NNFCM) and T(omega) is calculated using the non-equilibrium Green's function formalism. We show that by imposing partial fixed boundary conditions it is possible to restrict contributions of the in-plane phonon modes to T(omega) at low energy. On the contrary, the transmission functions of out-of-plane phonon modes can be diminished by proper antidot or isotope arrangements. In particular, we show that a periodic array of them leads to sharp dips in the transmission function at certain frequencies omega(nu) which can be pre-defined as desired by controlling their relative distance and size. With this, we demonstrated that by adequate engineering it is possible to govern the magnitude of the ballistic transmission functions T(omega) in graphene nanoribbons. We discuss the implications of these results in the design of controlled thermal transport at the nanoscale as well as in the enhancement of thermo-electric features of graphene-based materials.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000358675900010 Publication Date 2015-07-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0957-4484;1361-6528; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.44 Times cited 5 Open Access
Notes ; Discussions with C E Repetto, C R Stia and K H Michel are gratefully acknowledged. This work was partially supported by the Flemish Science Foundation (FWO-Vl) and PIP 11220090100392 of CONICET (Argentina). We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. ; Approved Most recent IF: 3.44; 2015 IF: 3.821
Call Number c:irua:127186 Serial 3759
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Author Kapra, A.V.; Vodolazov, D.Y.; Misko, V.R.
Title Vortex transport in a channel with periodic constrictions Type A1 Journal article
Year 2013 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech
Volume (down) 26 Issue 9 Pages 095010-95011
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract By numerically solving the time-dependent Ginzburg-Landau equations in a type-II superconductor, characterized by a critical temperature T-c1, and the coherence length xi(1), with a channel formed by overlapping rhombuses (diamond-like channel) made of another type-II superconductor, characterized, in general, by different T-c2 and xi(2), we investigate the dynamics of driven vortex matter for varying parameters of the channel: the width of the neck connecting the diamond cells, the cell geometry, and the ratio between the coherence lengths in the bank and the channel. We analyzed samples with periodic boundary conditions (which we call 'infinite' samples) and finite-size samples (with boundaries for vortex entry/exit), and we found that by tuning the channel parameters, one can manipulate the vortex dynamics, e.g., change the transition from flux-pinned to flux-flow regime and tune the slope of the IV-curves. In addition, we analyzed the effect of interstitial vortices on these characteristics. The critical current of this device was studied as a function of the applied magnetic field, j(c)(H). The function j(c)(H) reveals a striking commensurability peak, in agreement with recent experimental observations. The obtained results suggest that the diamond channel, which combines the properties of pinning arrays and flux-guiding channels, can be a promising candidate for potential use in devices controlling magnetic flux motion.
Address
Corporate Author Thesis
Publisher Place of Publication Bristol Editor
Language Wos 000323073800016 Publication Date 2013-07-30
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 2 Open Access
Notes ; This work was supported by the 'Odysseus' Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 2.878; 2013 IF: 2.796
Call Number UA @ lucian @ c:irua:110737 Serial 3898
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Author Sun, S.R.; Kolev, S.; Wang, H.X.; Bogaerts, A.
Title Coupled gas flow-plasma model for a gliding arc: investigations of the back-breakdown phenomenon and its effect on the gliding arc characteristics Type A1 Journal article
Year 2017 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T
Volume (down) 26 Issue 26 Pages 015003
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We present a 3D and 2D Cartesian quasi-neutral plasma model for a low current argon gliding arc discharge, including strong interactions between the gas flow and arc plasma column.

The 3D model is applied only for a short time of 0.2 ms due to its huge computational cost. It mainly serves to verify the reliability of the 2D model. As the results in 2D compare well with those in 3D, they can be used for a better understanding of the gliding arc basic characteristics. More specifically, we investigate the back-breakdown phenomenon induced by an artificially controlled plasma channel, and we discuss its effect on the gliding arc characteristics. The

back-breakdown phenomenon, or backward-jump motion of the arc, as observed in the experiments, results in a drop of the gas temperature, as well as in a delay of the arc velocity with respect to the gas flow velocity, allowing more gas to pass through the arc, and thus increasing the efficiency of the gliding arc for gas treatment applications.
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Publisher Place of Publication Editor
Language Wos 000419253000001 Publication Date 2016-11-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1361-6595 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.302 Times cited 9 Open Access OpenAccess
Notes This work is financially supported by the Methusalem financing, by the Fund for Scientific Research Flanders (FWO) and by the IAP/7 (Inter-university Attraction Pole) program ‘Physical Chemistry of Plasma-Surface Interactions’ from the Belgian Federal Office for Science Policy (BELSPO). The work was carried out in part using the Turing HPC infrastructure of the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the Universiteit Antwerpen. This work was also supported by the National Natural Science Foundation of China (Grant Nos. 11275021, 11575019). S R Sun thanks the financial support from the China Scholarship Council. Approved Most recent IF: 3.302
Call Number PLASMANT @ plasmant @ c:irua:138993 Serial 4337
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