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Author Saviuc, I.; Van Passel, S.; Peremans, H.
Title Integrating PV+battery residential microgrids in distribution networks : how is the point of common coupling agreed upon? Type H1 Book chapter
Year 2020 Publication Abbreviated Journal
Volume Issue Pages 150-164
Keywords H1 Book chapter; Economics; Engineering sciences. Technology; Engineering Management (ENM)
Abstract The anticipated development of decentralized electricity generation is expected to strengthen the opportunities of prosumers in the residential areas of cities, in line with the predicted establishment of renewable energy generation and storage. Based on academic research and on successful case studies, the opportunity for residential prosumers to organize in microgrids emerges as a viable and promising solution. This paper focuses on microgrids that are planned to generate electricity with a PV unit and use a shared storage system, and that opt to have a connection with the main grid. However, the point of common coupling needs to be agreed first between the microgrid operator and the network operator, and this agreement is determined by several factors and conditions beyond the basic technical and regulatory requirements. A survey of academic literature on the determinant factors for such an agreement exposes the fact that current research either focuses on the integration of individual prosumers in the main grid, or regards the point of common coupling as a given component of microgrids. We argue that neither of the two approaches is helpful in the case of microgrids vs. main grid, seeing as the agreement is not self-evident under just any circumstances, nor can the microgrid be equated to a single, large prosumer. Therefore this short paper compiles a set of determinant factors for the microgrid integration, as they emerge from academic literature, with the aim to document further research needs and support the discussion on microgrid integration.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2020-04-08
Series Editor Series Title Abbreviated Series Title (down) Sustainable Energy for Smart Cities : First EAI International Conference, SESC 2019, Braga, Portugal, December 4–6, 2019: proceedings
Series Volume Series Issue Edition
ISSN ISBN 978-3-030-45693-1 Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:168515 Serial 6932
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Author Einhäupl, P.; Krook, J.; Svensson, N.; Van Acker, K.; Van Passel, S.
Title Enhanced landfill mining at the REMO site : assessing stakeholders' perspectives for implementation Type P3 Proceeding
Year 2018 Publication Abbreviated Journal
Volume Issue Pages
Keywords P3 Proceeding; Engineering sciences. Technology; Engineering Management (ENM)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title (down) Proceedings of the 4th International Symposium on Enhanced Landfill Mining, February 5-6, 2018, Mechelen, Belgium / Jones, Peter Tom [edit.]; Machiels, Lieven [edit.]
Series Volume Series Issue Edition
ISSN ISBN 978-90-828259-0-9 Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:161512 Serial 6194
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Author Khalil-Allafi, J.; Amin-Ahmadi, B.
Title The effect of chemical composition on enthalpy and entropy changes of martensitic transformations in binary NiTi shape memory alloys Type P3 Proceeding
Year 2009 Publication Journal Of Alloys And Compounds Abbreviated Journal J Alloy Compd
Volume 487 Issue Pages 363-366
Keywords P3 Proceeding; Condensed Matter Theory (CMT)
Abstract In the present research work the binary NiTi alloys with various compositions in the range of 50.351 at.% Ni were used. Samples have been annealed at 850 °C for 15 min and then quenched in water. In order to characterize transformation temperatures and enthalpy changes of the forward and the reverse martensitic transformation, Differential Scanning Calorimetric (DSC) experiments were performed. The enthalpy and entropy changes as a function of Ni atomic content have been thermodynamically investigated. Results show that enthalpy and entropy changes of martensitic transformation decrease when Ni atomic content increases. The variation of enthalpy and entropy of martensitic transformation with Ni content in binary NiTi alloys were explained by thermodynamic parameters and electron concentration of alloy (e/a) respectively.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000272521900073 Publication Date 2009-07-31
Series Editor Series Title Abbreviated Series Title (down) Proceedings of the 22nd International Conference on the Physics of Semiconductors
Series Volume Series Issue Edition
ISSN 0925-8388; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.133 Times cited 30 Open Access
Notes Approved Most recent IF: 3.133; 2009 IF: 2.135
Call Number UA @ lucian @ c:irua:122040 Serial 804
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Author Kuppens, T.; Van Dael, M.; Vanreppelen, K.; Carleer, R.; Yperman, J.; Schreurs, S.; Van Passel, S.
Title Techno-economic assessment of pyrolysis char production and application : a review Type P1 Proceeding
Year 2014 Publication Abbreviated Journal
Volume Issue Pages 67-72
Keywords P1 Proceeding; Engineering sciences. Technology
Abstract Many organic residue streams such as pig manure are not or inefficiently used, although they can be converted into valuable materials, as well as energy, using pyrolysis. The yield of the pyrolysis products (i.e. oil, gas and char) is dependent on the process conditions and the feedstock used. Char as a soil amendment or activated carbon are interesting options for valorization of biomass residues. Here, a review is presented of the techno-economic potential of both valorization options based on literature and own experiments with wood from phytoremediation, particle board and waste from beer production. The term “biochar” is specifically used to designate pyrolysis char that is intentionally applied to soil in order to enhance its structure and fertility. Biochar applications are often also motivated by the objective of climate change mitigation. Two main disadvantages for the economic feasibility of biochar applications have been discerned. Firstly, carbon sequestration in agricultural crops and soils is not yet eligible under the Clean Development Mechanism. Secondly, the impact of biochar on crop productivity is unclear. Activated carbon (AC) seems to have interesting adsorption characteristics resulting in potentially high sales prices. A preliminary techno-economic assessment showed that AC production is preferred above oil production for wood from phytoremediation as long as the market price of 2 kEUR.t(-1) for commercially available ACs can be attained. Whenever a feedstock with high nitrogen content is available (e.g. particle board with melamine urea formaldehyde resin), even higher market prices might be attained. This study shows that valorization of the pyrolysis char might be an answer to the slow adoption of pyrolysis in commercial applications. Focus in research and development, for instance in future research with regard to pig manure valorization, should therefore be on sustainable products with high economic value and direct utilization potential.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000346540000012 Publication Date
Series Editor Series Title Abbreviated Series Title (down) International Conference on BioMass (iconBM 2014), 4-7 May 2014, Florence, Italy / Ranzi, Eliseo [edit.]; et al.
Series Volume 37 Series Issue Edition
ISSN 978-88-95608-28-0 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 8 Open Access
Notes ; ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:127547 Serial 6265
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Author De Backer, A.; De Wael, A.; Gonnissen, J.; Martinez, G.T.; Béché, A.; MacArthur, K.E.; Jones, L.; Nellist, P.D.; Van Aert, S.
Title Quantitative annular dark field scanning transmission electron microscopy for nanoparticle atom-counting: What are the limits? Type P1 Proceeding
Year 2015 Publication Journal of physics : conference series Abbreviated Journal
Volume 644 Issue 644 Pages 012034
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract Quantitative atomic resolution annular dark field scanning transmission electron microscopy (ADF STEM) has become a powerful technique for nanoparticle atom-counting. However, a lot of nanoparticles provide a severe characterisation challenge because of their limited size and beam sensitivity. Therefore, quantitative ADF STEM may greatly benefit from statistical detection theory in order to optimise the instrumental microscope settings such that the incoming electron dose can be kept as low as possible whilst still retaining single-atom precision. The principles of detection theory are used to quantify the probability of error for atom-counting. This enables us to decide between different image performance measures and to optimise the experimental detector settings for atom-counting in ADF STEM in an objective manner. To demonstrate this, ADF STEM imaging of an industrial catalyst has been conducted using the near-optimal detector settings. For this experiment, we discussed the limits for atom-counting diagnosed by combining a thorough statistical method and detailed image simulations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000366826200034 Publication Date 2015-10-13
Series Editor Series Title Abbreviated Series Title (down) Electron Microscopy and Analysis Group Conference (EMAG), JUN 02-JUL 02, 2015, Manchester, ENGLAND
Series Volume Series Issue Edition
ISSN 1742-6588 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project funding (G.0368.15N, G.0369.15N, and G.0374.15N) and a PhD research grant to A De Backer. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative-I3), ERC Starting Grant 278510 Vortex, and the UK Engineering and Physical Sciences Research Council (EP/K032518/1). The authors acknowledge Johnson-Matthey for providing the sample and PhD funding to K E MacArthur. A Rosenauer is acknowledged for providing the STEMsim program.; esteem2jra2; ECASJO; Approved Most recent IF: NA
Call Number c:irua:130314 c:irua:130314 Serial 4050
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Author Misko, V.R.; Fomin, V.M.; Devreese, J.T.; Moshchalkov, V.V.
Title Stability of vortex-antivortex “molecules” in mesoscopic superconducting triangles Type A1 Journal article
Year 2005 Publication Abbreviated Journal
Volume Issue Pages 191-196
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract We have revealed thermodynamically stable vortex-antivortex configurations in mesoscopic type I superconducting equilateral triangles. The revealed effect is explained by two factors: (i) vortex confinement in mesoscopic triangles and (ii) appearance of the vortex-antivortex repulsion in mesoscopic type I superconductor triangles in the vicinity of the dual point. The stability of the obtained solutions is examined as a function of material and external parameters – the Ginzburg-Landau parameter K and temperature – as well as a function of a distortion of the sample's shape. The vortex-antivortex. “molecule” turns out to be stable in a wide range of the parameters that makes it possible its experimental visualization.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000234363700030 Publication Date 2007-11-30
Series Editor Series Title Abbreviated Series Title (down) 3rd International Symposium on Mesoscopic Superconductivity and, Spintronics, MAR 01-04, 2004, Atsug
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:103704 Serial 3134
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Author Kuppens, T.; Van Dael, M.; Maggen, J.; Vanreppelen, K.; Yperman, J.; Carleer, R.; Elen, H.; Van Passel, S.
Title Techno-economic assessment of different conversion pathways for pyrolysis char from pig manure Type P1 Proceeding
Year 2014 Publication Abbreviated Journal
Volume Issue Pages 901-911
Keywords P1 Proceeding; Engineering sciences. Technology
Abstract The amount of animal manure that can be brought back to agricultural land is limited by legislation. Because pig manure is available in too large quantities in some areas, we investigate the techno-economic feasibility of converting it into valuable products. First, slurry is separated in water, a thick fraction and a fertilizer concentrate poor in phosphate. Then, the thick fraction is dried and pyrolyzed. Our goal is to identify the optimal pyrolysis and activation conditions for the production of biochar or activated carbon. The latter has interesting adsorption characteristics due to the presence of nitrogen. It can also be used as a soil amendment as it improves biomass quantity and quality. On top, it immobilizes toxic elements and stores carbon in the soil. Char thus has many interesting characteristics and can be valued in different ways. The economic feasibility has been explored by a first techno-economic modelling iteration. The critical factors influencing the feasibility are identified by Monte Carlo simulations for further improvement of the process design.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title (down) 22nd European Biomass Conference and Exhibition : Setting the Course for a Biobased Economy, 23-26 June 2014, Hamburg, Germany : conference proceedings
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes ; ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:127546 Serial 6263
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Author Sels, D.; Sorée, B.; Groeseneken, G.
Title 2-D rotational invariant multi sub band Schrödinger-Poisson solver to model nanowire transistors Type A1 Journal article
Year 2010 Publication Abbreviated Journal
Volume Issue Pages 85-88
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract
Address
Corporate Author Thesis
Publisher Pisa University Press Place of Publication Pisa Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title (down) 14th International Workshop on Computational Electronics
Series Volume Series Issue Edition
ISSN 978-1-4244-9381-4 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:91699 Serial 6
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Author Fomin, V.M.; Misko, V.R.; Devreese, J.T.; Moshchalkov, V.V.
Title Phase boundaries of superconducting mesoscopic square loops Type A1 Journal article
Year 1997 Publication Abbreviated Journal
Volume Issue Pages 835-838
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication S.l. Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title (down) 12th International Conference on the Electronic Properties of Two-Dimensional Systems (EP2DS), Tokyo
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:20370 Serial 2578
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Author Müller, E.; Kruse, P.; Gerthsen, D.; Schowalter, M.; Rosenauer, A.; Lamoen, D.; Kling, R.
Title Measurement of the mean inner potential of ZnO nanorods by transmission electron holography Type A1 Journal article
Year 2005 Publication Microscopy of Semiconducting Materials Abbreviated Journal
Volume 107 Issue Pages 303-306
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Berlin Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title SPRINGER PROCEEDINGS IN PHYSICS Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0930-8989 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:72914 Serial 1962
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Author Engelmann, Y.; Bogaerts, A.; Neyts, E.C.
Title Thermodynamics at the nanoscale : phase diagrams of nickel-carbon nanoclusters and equilibrium constants for face transitions Type A1 Journal article
Year 2014 Publication Nanoscale Abbreviated Journal Nanoscale
Volume 6 Issue Pages 11981-11987
Keywords A1 Journal article; PLASMANT
Abstract Using reactive molecular dynamics simulations, the melting behavior of nickelcarbon nanoclusters is examined. The phase diagrams of icosahedral and Wulff polyhedron clusters are determined using both the Lindemann index and the potential energy. Formulae are derived for calculating the equilibrium constants and the solid and liquid fractions during a phase transition, allowing more rational determination of the melting temperature with respect to the arbitrary Lindemann value. These results give more insight into the properties of nickelcarbon nanoclusters in general and can specifically be very useful for a better understanding of the synthesis of carbon nanotubes using the catalytic chemical vapor deposition method.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000343000800049 Publication Date 2014-07-24
Series Editor Series Title Abbreviated Series Title (down)
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 20 Open Access
Notes Approved Most recent IF: 7.367; 2014 IF: 7.394
Call Number UA @ lucian @ c:irua:119408 Serial 3636
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Author Milošević, M.V.; Perali, A.
Title Emergent phenomena in multicomponent superconductivity: an introduction to the focus issue Type A1 Journal article
Year 2015 Publication Superconductor Science & Technology Abbreviated Journal Supercond Sci Tech
Volume 28 Issue 28 Pages 060201
Keywords A1 Journal article; CMT
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000354110200001 Publication Date 2015-04-24
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0953-2048;1361-6668; ISBN Additional Links
Impact Factor 2.878 Times cited 41 Open Access
Notes ; ; Approved Most recent IF: 2.878; 2015 IF: 2.325
Call Number UA @ lucian @ Serial 3945
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Author Roose, D.; Leroux, F.; De Vocht, N.; Guglielmetti, C.; Pintelon, I.; Adriaensen, D.; Ponsaerts, P.; Van der Linden, A.; Bals, S.
Title Multimodal imaging of micron-sized iron oxide particles following in vitro and in vivo uptake by stem cells: down to the nanometer scale Type A1 Journal article
Year 2014 Publication Contrast Media & Molecular Imaging Abbreviated Journal Contrast Media Mol I
Volume 9 Issue 6 Pages 400-408
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract In this study, the interaction between cells and micron-sized paramagnetic iron oxide (MPIO) particles was investigated by characterizing MPIO in their original state, and after cellular uptake in vitro as well as in vivo. Moreover, MPIO in the olfactory bulb were studied 9 months after injection. Using various imaging techniques, cell-MPIO interactions were investigated with increasing spatial resolution. Live cell confocal microscopy demonstrated that MPIO co-localize with lysosomes after in vitro cellular uptake. In more detail, a membrane surrounding the MPIO was observed by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). Following MPIO uptake in vivo, the same cell-MPIO interaction was observed by HAADF-STEM in the subventricular zone at 1 week and in the olfactory bulb at 9 months after MPIO injection. These findings provide proof for the current hypothesis that MPIO are internalized by the cell through endocytosis. The results also show MPIO are not biodegradable, even after 9 months in the brain. Moreover, they show the possibility of HAADF-STEM generating information on the labeled cell as well as on the MPIO. In summary, the methodology presented here provides a systematic route to investigate the interaction between cells and nanoparticles from the micrometer level down to the nanometer level and beyond.
Address EMAT, University of Antwerp, Antwerp, Belgium; Bio-Imaging Lab, University of Antwerp, Antwerp, Belgium; Laboratory of Experimental Hematology, University of Antwerp, Antwerp, Belgium
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000346172100002 Publication Date 2014-04-22
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 1555-4309; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.307 Times cited 8 Open Access Not_Open_Access
Notes IAP-PAI; 262348 ESMI; Hercules Type 1: AUHA 09/001 and AUHA 11/01 Approved Most recent IF: 3.307; 2014 IF: 2.923
Call Number UA @ lucian @ Serial 3938
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Author Kozák, T.; Vlček, J.
Title A parametric model for reactive high-power impulse magnetron sputtering of films Type A1 Journal article
Year 2016 Publication Journal Of Physics D-Applied Physics Abbreviated Journal J Phys D Appl Phys
Volume 49 Issue 49 Pages 055202
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract We present a time-dependent parametric model for reactive HiPIMS deposition of films. Specific features of HiPIMS discharges and a possible increase in the density of the reactive gas in front of the reactive gas inlets placed between the target and the substrate are considered in the model. The model makes it possible to calculate the compound fractions in two target layers and in one substrate layer, and the deposition rate of films at fixed partial pressures of the reactive and inert gas. A simplified relation for the deposition rate of films prepared using a reactive HiPIMS is presented. We used the model to simulate controlled reactive HiPIMS depositions of stoichiometric ZrO2 films, which were recently carried out in our laboratories with two different configurations of the O2 inlets in front of the sputtered target. The repetition frequency was 500 Hz at the deposition-averaged target power densities of 5 Wcm−2 and 50 Wcm−2 with a pulse-averaged target power density up to 2 kWcm−2. The pulse durations were 50 μs and 200 μs. Our model calculations show that the to-substrate O2 inlet provides systematically lower compound fractions in the target surface layer and higher compound fractions in the substrate surface layer, compared with the to-target O2 inlet. The low compound fractions in the target surface layer (being approximately 10% at the depositionaveraged target power density of 50 Wcm−2 and the pulse duration of 200 μs) result in high deposition rates of the films produced, which are in agreement with experimental values.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000368944100016 Publication Date 2015-12-16
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0022-3727 ISBN Additional Links
Impact Factor 2.588 Times cited 25 Open Access
Notes This work was supported by the Czech Science Foundation under Project No. GA14–03875S Approved Most recent IF: 2.588
Call Number PLASMANT @ plasmant @ Serial 3994
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Author Covaci, L.; Berciu, M.
Title Survival of the Dirac points in rippled graphene Type A1 Journal article
Year 2008 Publication Physical Review Letters Abbreviated Journal Phys Rev Lett
Volume 100 Issue 25 Pages 256405
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract We study the effects of the rippling of a graphene sheet on quasiparticle dispersion. This is achieved using a generalization to the honeycomb lattice of the momentum average approximation, which is accurate for all coupling strengths and at all energies. We show that even though the position of the Dirac points may move and the Fermi speed can be renormalized significantly, quasiparticles with very long lifetimes survive near the Dirac points even for very strong couplings.
Address Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada, V6T 1Z1
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000257230500047 Publication Date 2008-06-26
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Additional Links
Impact Factor 8.462 Times cited 15 Open Access
Notes Approved Most recent IF: 8.462; 2008 IF: 7.180
Call Number UA @ lucian @ Serial 4010
Permanent link to this record
 

 
Author Zanaga, D.; Altantzis, T.; Sanctorum, J.; Freitag, B.; Bals, S.
Title An alternative approach for ζ-factor measurement using pure element nanoparticles Type A1 Journal article
Year 2016 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 164 Issue 164 Pages 11-16
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract It is very challenging to measure the chemical composition of hetero nanostructures in a reliable and quantitative manner. Here, we propose a novel and straightforward approach that can be used to quantify energy dispersive X-ray spectra acquired in a transmission electron microscope. Our method is based on a combination of electron tomography and the so-called ζ-factor technique. We will demonstrate the reliability of our approach as well as its applicability by investigating Au-Ag and Au-Pt hetero nanostructures. Given its simplicity, we expect that the method could become a new standard in the field of chemical characterization using electron microscopy.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000373526200002 Publication Date 2016-03-10
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0304-3991 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.843 Times cited 19 Open Access OpenAccess
Notes The authors acknowledge financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS) and the European Union under the FP7 (Integrated Infrastructure Initiative N. 312483 – ESTEEM2). The authors would also like to thank Luis M. Liz-Marzán, Ana Sánchez-Iglesias, Stefanos Mourdikoudis and Cristina Fernández-López for sample provision and useful discussions.; esteem2jra4; ECASSara; (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); Approved Most recent IF: 2.843
Call Number EMAT @ emat @ Serial 4019
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Author Covaci, L.; Marsiglio, F.
Title Proximity effect and Josephson current in clean strong/weak/strong superconducting trilayers Type A1 Journal article
Year 2006 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 73 Issue 1 Pages 014503
Keywords A1 Journal article
Abstract Recent measurements of the Josephson critical current through LSCO/LCO/LSCO thin films showed an unusually large proximity effect. Using the Bogoliubov-de Gennes equations for a tight-binding Hamiltonian we describe the proximity effect in weak links between a superconductor with critical temperature T-c and one with critical temperature T-c('), where T-c > T-c('). The weak link (N-') is therefore a superconductor above its own critical temperature and the superconducting regions are considered to have either s-wave or d-wave symmetry. We note that the proximity effect is enhanced due to the presence of superconducting correlations in the weak link. The dc Josephson current is calculated, and we obtain a nonzero value for temperatures greater than T-c(') for sizes of the weak links that can be almost an order of magnitude greater than the conventional coherence length. Considering pockets of superconductivity in the N-' layer, we show that this can lead to an even larger effect on the Josephson critical current by effectively shortening the weak link.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000235009000103 Publication Date 2006-01-03
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 1098-0121 ISBN Additional Links
Impact Factor 3.836 Times cited 31 Open Access
Notes Approved Most recent IF: 3.836; 2006 IF: 3.107
Call Number UA @ lucian @ Serial 4427
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Author Kirilenko, D.A.; Brunkov, P.N.
Title Measuring the height-to-height correlation function of corrugation in suspended graphene Type A1 Journal article
Year 2016 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 165 Issue 165 Pages 1-7
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract Nanocorrugation of 2D crystals is an important phenomenon since it affects their electronic and mechanical properties. The corrugation may have various sources; one of them is flexural phonons that, in particular, are responsible for the thermal conductivity of graphene. A study of corrugation of just the suspended graphene can reveal much of valuable information on the physics of this complicated phenomenon. At the same time, the suspended crystal nanorelief can hardly be measured directly because of high flexibility of the 2D crystal. Moreover, the relief portion related to rapid out-of-plane oscillations (flexural phonons) is also inaccessible by such measurements. Here we present a technique for measuring the Fourier components of the height-height correlation function H(q) of suspended graphene which includes the effect of flexural phonons. The technique is based on the analysis of electron diffraction patterns. The H(q) is measured in the range of wavevectors q approximately 0.4-4.5nm(-1). At the upper limit of this range H(q) does follow the T/kappaq(4) law. So, we measured the value of suspended graphene bending rigidity kappa=1.2+/-0.4eV at ambient temperature T approximately 300K. At intermediate wave vectors, H(q) follows a slightly weaker exponent than theoretically predicted q(-3.15) but is closer to the results of the molecular dynamics simulation. At low wave vectors, the dependence becomes even weaker, which may be a sign of influence of charge carriers on the dynamics of undulations longer than 10nm. The technique presented can be used for studying physics of flexural phonons in other 2D materials.
Address Ioffe Institute, Politekhnicheskaya ul. 26, 194021 St-Petersburg, Russia; ITMO University, Kronverksky pr. 49, 197101 St. Petersburg, Russia
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000375946200001 Publication Date 2016-03-28
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0304-3991 ISBN Additional Links
Impact Factor 2.843 Times cited 3 Open Access
Notes D.K. thanks the RFBR (Grant no. 16-32-60165) for the partial support of this research. The work was carried out in part at the Joint Research Center “Material Science and Characterization in Advanced Technologies” (St-Petersburg, Russia) under the financial support from the Ministry of Education and Science of the Russian Federation (Agreement 14.621.21.0007, 04.12.2014, id RFMEFI62114X0007, the use of the Jeol JEM-2100F microscope) and at EMAT, Universiteit Antwerpen (Antwerpen, Belgium), (the use of the FEI Tecnai G2 microscope). Approved Most recent IF: 2.843
Call Number EMAT @ emat @ Serial 4124
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Author Bogaerts, A.
Title Glow discharge optical spectroscopy and mass spectrometry Type A1 Journal article
Year 2016 Publication Abbreviated Journal
Volume Issue Pages
Keywords A1 Journal article; PLASMANT
Abstract Atomic Spectroscopy Optical (atomic absorption spectroscopy, AAS; atomic emission spectroscopy, AES; atomic fluorescence spectroscopy, AFS; and optogalvanic spectroscopy) and mass spectrometric (magnetic sector, quadrupole mass analyzer, QMA; quadrupole ion trap, QIT; Fourier transform ion cyclotron resonance, FTICR; and time-of-flight, TOF) instrumentation are well suited for coupling to the glow discharge (GD). The GD is a relatively simple device. A potential gradient (500–1500 V) is applied between an anode and a cathode. In most cases, the sample is also the cathode. A noble gas (mostly Ar) is introduced into the discharge region before power initiation. When a potential is applied, electrons are accelerated toward the anode. As these electrons accelerate, they collide with gas atoms. A fraction of these collisions are of sufficient energy to remove an electron from a support gas atom, forming an ion. These ions are, in turn, accelerated toward the cathode. These ions impinge on the surface of the cathode, sputtering sample atoms from the surface. Sputtered atoms that do not redeposit on the surface diffuse into the excitation/ionization regions of the plasma where they can undergo excitation and/or ionization via a number of collisional processes, and the photons or ions created in this way can be detected with optical emission spectroscopy or mass spectrometry. GD sources offer a number of distinct advantages that make them well suited for specific types of analyses. These sources afford direct analysis of solid samples, thus minimizing the sample preparation required for analysis. The nature of the plasma also provides mutually exclusive atomization and excitation processes that help to minimize the matrix effects that plague so many other elemental techniques. In recent years, there is also increasing interest for using GD sources for liquid and gas analyses. In this article, first, the principles of operation of the GD plasma are reviewed, with an emphasis on how those principles relate to optical spectroscopy and mass spectrometry. Basic applications of the GD techniques are considered next. These include bulk analysis, surface analysis, and the analysis of solution and gaseous samples. The requirements necessary to obtain optical information are addressed following the analytical applications. This article focuses on the instrumentation needed to make optical measurements using the GD as an atomization/excitation source. Finally, mass spectrometric instrumentation and interfaces are addressed as they pertain to the use of a GD plasma as an ion source. GD sources provide analytically useful gas-phase species from solid samples. These sources can be interfaced with a variety of spectroscopic and spectrometric instruments for both quantitative and qualitative analyses.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2006-09-11
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN ISBN Additional Links
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number PLASMANT @ plasmant @ Serial 4282
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Author Zhang, F.; Inokoshi, M.; Batuk, M.; Hadermann, J.; Naert, I.; Van Meerbeek, B.; Vleugels, J.
Title Strength, toughness and aging stability of highly-translucent Y-TZP ceramics for dental restorations Type A1 Journal article
Year 2016 Publication Dental Materials Abbreviated Journal Dent Mater
Volume 32 Issue 32 Pages e327-e337
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract OBJECTIVE: The aim was to evaluate the optical properties, mechanical properties and aging stability of yttria-stabilized zirconia with different compositions, highlighting the influence of the alumina addition, Y2O3 content and La2O3 doping on the translucency. METHODS: Five different Y-TZP zirconia powders (3 commercially available and 2 experimentally modified) were sintered under the same conditions and characterized by X-ray diffraction with Rietveld analysis and scanning electron microscopy (SEM). Translucency (n=6/group) was measured with a color meter, allowing to calculate the translucency parameter (TP) and the contrast ratio (CR). Mechanical properties were appraised with four-point bending strength (n=10), single edge V-notched beam (SEVNB) fracture toughness (n=8) and Vickers hardness (n=10). The aging stability was evaluated by measuring the tetragonal to monoclinic transformation (n=3) after accelerated hydrothermal aging in steam at 134 degrees C, and the transformation curves were fitted by the Mehl-Avrami-Johnson (MAJ) equation. Data were analyzed by one-way ANOVA, followed by Tukey's HSD test (alpha=0.05). RESULTS: Lowering the alumina content below 0.25wt.% avoided the formation of alumina particles and therefore increased the translucency of 3Y-TZP ceramics, but the hydrothermal aging stability was reduced. A higher yttria content (5mol%) introduced about 50% cubic zirconia phase and gave rise to the most translucent and aging-resistant Y-TZP ceramics, but the fracture toughness and strength were considerably sacrificed. 0.2mol% La2O3 doping of 3Y-TZP tailored the grain boundary chemistry and significantly improved the aging resistance and translucency. Although the translucency improvement by La2O3 doping was less effective than for introducing a substantial amount of cubic zirconia, this strategy was able to maintain the mechanical properties of typical 3Y-TZP ceramics. SIGNIFICANCE: Three different approaches were compared to improve the translucency of 3Y-TZP ceramics.
Address KU Leuven, Department of Materials Engineering, Kasteelpark Arenberg 44, Belgium
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000389516400003 Publication Date 2016-10-06
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0109-5641 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.07 Times cited Open Access
Notes The authors acknowledge the Research Fund of KU Leu- ven under project 0T/10/052 and the Fund for Scientific Research Flanders (FWO-Vlaanderen) under grant G.0431.10N. F. Zhang thanks the Research Fund of KU Leuven for her post- doctoral fellowship (PDM/15/153). We thank M. Peumans for the translucency measurements. Approved Most recent IF: 4.07
Call Number EMAT @ emat @ c:irua:136821 Serial 4313
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Author Zalfani, M.; Hu, Z.-Y.; Yu, W.-B.; Mahdouani, M.; Bourguig, R.; Wu, M.; Li, Y.; Van Tendeloo, G.; Djoued, Y.; Su, B.-L.
Title BiVO4/3DOM TiO2 nanocomposites: Effect of BiVO4 as highly efficient visible light sensitizer for highly improved visible light photocatalytic activity in the degradation of dye pollutants Type A1 Journal article
Year 2016 Publication Applied Catalysis B-Environmental Abbreviated Journal Appl Catal B-Environ
Volume 205 Issue 205 Pages 121-132
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A series of BiVO4/3DOM TiO2 nanocomposites have been synthesized and their photocatalytic activity was investigated under visible light irradiation using the RhB dye as model pollutant molecule in an aqueous solution. The effect of the amount of BiVO4 as visible light sensitizer on the photocatalytic activity of BiVO4/3DOM TiO2 nanocomposites was highlighted. The heterostructured composite system leads to much higher photocatalytic efficiencies than bare 3DOM TiO2 and BiVO4 nanoparticles. As the proportion of BiVO4 in BiVO4/3DOM TiO2 nanocomposites increases from 0.04 to 0.6, the photocatalytic performance of the BiVO4/3DOM TiO2 nanocomposites increases and then decreases after reaching a maximum at 0.2. This improvement in photocatalytic perfomance is related to 1) the interfacial electron transfer efficiency between the coupled materials, 2) the 3DOM TiO2 inverse opal structure with interconnected pores providing an easy mass transfer of the reactant molecules and high accessibility to the active sites and large surface area and 3) the effect of light sensitizer of BiVO4. Intensive studies on structural, textural, optical and surface properties reveal that the electronic interactions between BiVO4 and TiO2 lead to an improved charge separation of the coupled BiVO4/TiO2 system. The photogenerated charge carrier densities increase with increasing the BiVO4 content, which acts as visible light sensitizer to the TiO2 and is responsible for the enhancement in the rate of photocatalytic degradation. However, the photocatalytic activity is reduced when the BiVO4 amount is much higher than that of 3DOM TiO2. Two reasons could account for this behavior. First, with increasing BiVO4 content, the photogenerated electron/hole pairs are accumulated at the surface of the BiVO4 nanoparticles and the recombination rate increases as shown by the PL results. Second, decreasing the amount of 3DOM TiO2 in the nanocomposite decreases the surface area as shown by the BET results. Moreover, the poor adsorptive properties of the BiVO4 photocatalyst also affect the photocatalytic performance, in particular at higher BiVO4 content. The present work demonstrates that BiVO4/3DOM TiO2 is a very promising heterojunction system for visible light photocatalytic applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000393931000013 Publication Date 2016-12-08
Series Editor Series Title Abbreviated Series Title (down)
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 52 Open Access OpenAccess
Notes Z. Y. Hu and G. Van Tendeloo acknowledge support from the EC Framework 7 program ESTEEM2 (Reference 312483). Approved Most recent IF: 9.446
Call Number EMAT @ emat @ Serial 4323
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Author Schalm, O.; Crabbé, A.; Storme, P.; Wiesinger, R.; Gambirasi, A.; Grieten, E.; Tack, P.; Bauters, S.; Kleber, C.; Favaro, M.; Schryvers, D.; Vincze, L.; Terryn, H.; Patelli, A.
Title The corrosion process of sterling silver exposed to a Na2S solution: monitoring and characterizing the complex surface evolution using a multi-analytical approach Type A1 Journal article
Year 2016 Publication Applied Physics A-Materials Science & Processing Abbreviated Journal Appl Phys A-Mater
Volume 122 Issue 122 Pages 903
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract Many historical ‘silver’ objects are composed of sterling silver, a silver alloy containing small amounts of copper. Besides the dramatic impact of copper on the corrosion process, the chemical composition of the corrosion layer evolves continuously. The evolution of the surface during the exposure to a Na2S solution was monitored by means of visual observation at macroscopic level, chemical analysis at microscopic level and analysis at the nanoscopic level. The corrosion process starts with the preferential oxidation of copper, forming mixtures of oxides and sulphides while voids are being created beneath the corrosion layer. Only at a later stage, the silver below the corrosion layer is consumed. This results in the formation of jalpaite and at a later stage of acanthite. The acanthite is found inside the corrosion layer at the boundaries of jalpaite grains and as individual grains between the jalpaite grains but also as a thin film on top of the corrosion layer. The corrosion process could be described as a sequence of 5 subsequent surface states with transitions between these states.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000384753800033 Publication Date 2016-09-20
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0947-8396 ISBN Additional Links
Impact Factor 1.455 Times cited 9 Open Access
Notes The authors are grateful for the financial support by the EU-FP7 Grant PANNA No. 282998 and for the opportunity to perform SR-XPS measurements at the NanoESCA beamline of the Elettra storage ring, under the approval of the advisory Committee (Proposal No. 20135164), as well as the opportunity to perform XANES measurements at the DUBBLE beamline of the ESRF storage ring (Proposal No. 26-01-990). The authors are grateful for the financial support by the STIMPRO Project FFB150215 of the University of Antwerp. Pieter Tack is funded by a Ph.D. Grant of the Agency for Innovation by Science and Technology (IWT). We would also like to thank Peter Van den Haute for the XRD measurements that were performed at the University of Ghent. Approved Most recent IF: 1.455
Call Number EMAT @ emat @ Serial 4331
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Author Doğan, F.; Covaci, L.; Kim, W.; Marsiglio, F.
Title Emerging nonequilibrium bound state in spin-current–local-spin scattering Type A1 Journal article
Year 2009 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 80 Issue 10 Pages 104434
Keywords A1 Journal article
Abstract Magnetization reversal is a well-studied problem with obvious applicability in computer hard drives. One can accomplish a magnetization reversal in at least one of two ways: application of a magnetic field or through a spin current. The latter is more amenable to a fully quantum-mechanical analysis. We formulate and solve the problem whereby a spin current interacts with a ferromagnetic Heisenberg spin chain, to eventually reverse the magnetization of the chain. Spin flips are accomplished through both elastic and inelastic scattering. A consequence of the inelastic-scattering channel, when it is no longer energetically possible, is the occurrence of a nonequilibrium bound state, which is an emergent property of the coupled local plus itinerant spin system. For certain definite parameter values the itinerant spin lingers near the local spins for some time, before eventually leaking out as an outwardly diffusing state. This phenomenon results in spin-flip dynamics and filtering properties for this type of system.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000270383100077 Publication Date 2009-09-25
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 1098-0121 ISBN Additional Links
Impact Factor 3.836 Times cited Open Access
Notes Approved Most recent IF: 3.836; 2009 IF: 3.475
Call Number UA @ lucian @ Serial 4436
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Author Goodvin, G.L.; Covaci, L.; Berciu, M.
Title Holstein polarons near surfaces Type A1 Journal article
Year 2009 Publication Physical Review Letters Abbreviated Journal Phys Rev Lett
Volume 103 Issue 17 Pages 176402
Keywords A1 Journal article
Abstract We study the effects of a nearby surface on the spectral weight of a Holstein polaron, using the inhomogeneous momentum average approximation which is accurate over the entire range of electron-phonon (e-ph) coupling strengths. The broken translational symmetry is taken into account exactly. We find that the e-ph coupling gives rise to a large additional surface potential, with strong retardation effects, which may bind surface states even when they are not normally expected. The surface, therefore, has a significant effect and bulk properties are recovered only very far away from it. These results demonstrate that interpretation in terms of bulk quantities of spectroscopic data sensitive only to a few surface layers is not always appropriate.
Address Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000271164500042 Publication Date 2009-10-22
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Additional Links
Impact Factor 8.462 Times cited 8 Open Access
Notes Approved Most recent IF: 8.462; 2009 IF: 7.328
Call Number UA @ lucian @ Serial 4435
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Author Kim, W.; Covaci, L.; Marsiglio, F.
Title Impurity scattering of wave packets on a lattice Type A1 Journal article
Year 2006 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 74 Issue 20 Pages 205120
Keywords A1 Journal article
Abstract Quantum transport in a lattice is distinct from its counterpart in continuum media. Even a free wave packet travels differently in a lattice than in the continuum. We describe quantum scattering in a one-dimensional lattice and illustrate characteristics of quantum transport such as resonant transmission. In particular we examine the transport characteristics of a random trimer model. We demonstrate the real-time propagation of a wave packet and its phase shift due to impurity configurations. Spin-flip scattering is also taken into account in a spin-chain system. We show how individual spins in the chain evolve as a result of a spin-flip interaction between an incoming electron and a spin chain.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000242409400030 Publication Date 2006-11-27
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 1098-0121 ISBN Additional Links
Impact Factor 3.836 Times cited 14 Open Access
Notes Approved Most recent IF: 3.836; 2006 IF: 3.107
Call Number UA @ lucian @ Serial 4428
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Author Kim, W.; Covaci, L.; Marsiglio, F.
Title Hidden symmetries of electronic transport in a disordered one-dimensional lattice Type A1 Journal article
Year 2006 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 73 Issue 19 Pages 195109
Keywords A1 Journal article
Abstract Correlated, or extended, impurities play an important role in the transport properties of dirty metals. Here, we examine, in the framework of a tight-binding lattice, the transmission of a single electron through an array of correlated impurities. In particular we show that particles transmit through an impurity array in identical fashion, regardless of the direction of traversal. The demonstration of this fact is straightforward in the continuum limit, but requires a detailed proof for the discrete lattice. We also briefly demonstrate and discuss the time evolution of these scattering states, to delineate regions (in time and space) where the aforementioned symmetry is violated.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000237950400042 Publication Date 2006-05-11
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 1098-0121 ISBN Additional Links
Impact Factor 3.836 Times cited 5 Open Access
Notes Approved Most recent IF: 3.836; 2006 IF: 3.107
Call Number UA @ lucian @ Serial 4429
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Author Kim, W.; Covaci, L.; Dogan, F.; Marsiglio, F.
Title Quantum mechanics of spin transfer in coupled electron-spin chains Type A1 Journal article
Year 2007 Publication Epl Abbreviated Journal Epl-Europhys Lett
Volume 79 Issue 6 Pages 67004
Keywords A1 Journal article
Abstract The manner in which spin-polarized electrons interact with a magnetized thin film is currently described by a semi-classical approach. This in turn provides our present understanding of the spin transfer, or spin torque phenomenon. However, spin is an intrinsically quantum-mechanical quantity. Here, we make the first strides towards a fully quantum-mechanical description of spin transfer through spin currents interacting with a Heisenberg-coupled spin chain. Because of quantum entanglement, this requires a formalism based on the density matrix approach. Our description illustrates how individual spins in the chain time-evolve as a result of spin transfer.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000250409500023 Publication Date 2007-08-24
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0295-5075 ISBN Additional Links
Impact Factor 1.957 Times cited 3 Open Access
Notes Approved Most recent IF: 1.957; 2007 IF: 2.206
Call Number UA @ lucian @ Serial 4430
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Author Covaci, L.; Berciu, M.
Title Holstein polaron: The effect of coupling to multiple-phonon modes Type A1 Journal article
Year 2007 Publication Epl Abbreviated Journal Epl-Europhys Lett
Volume 80 Issue 6 Pages 67001
Keywords A1 Journal article
Abstract We investigate the effects of coupling to multiple-phonon modes on the properties of a Holstein polaron. To this end, we generalize the Momentum Average approximations MA((0)) and MA((1)) to deal with multiple-phonon modes. As for a single-phonon mode, these approximations are found to be numerically very efficient. They become exact for very weak or very strong couplings, and are highly accurate in the intermediate regimes, e.g. the spectral weights obey exactly the first six, respectively eight, sum rules. Our results show that the effect on ground-state properties is cumulative in nature. As a result, if the effective coupling to one mode is much larger than to all the others, this mode effectively determines the ground-state properties. However, even very weak coupling to a second phonon mode has important non-perturbational effects on the higher-energy spectrum, in particular on the dispersion and the phonon statistics of the polaron band. This has important consequences on the analysis and interpretation of data for real materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000251648300016 Publication Date 2007-11-30
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0295-5075 ISBN Additional Links
Impact Factor 1.957 Times cited 9 Open Access
Notes Approved Most recent IF: 1.957; 2007 IF: 2.206
Call Number UA @ lucian @ Serial 4431
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Author Marchand, D.; Covaci, L.; Berciu, M.; Franz, M.
Title Giant proximity effect in a phase-fluctuating superconductor Type A1 Journal article
Year 2008 Publication Physical Review Letters Abbreviated Journal Phys Rev Lett
Volume 101 Issue 9 Pages 097004
Keywords A1 Journal article
Abstract When a tunneling barrier between two superconductors is formed by a normal material that would be a superconductor in the absence of phase fluctuations, the resulting Josephson effect can undergo an enormous enhancement. We establish this novel proximity effect by a general argument as well as a numerical simulation and argue that it may underlie recent experimental observations of the giant proximity effect between two cuprate superconductors separated by a barrier made of the same material rendered normal by severe underdoping.
Address Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada V6T 1Z1
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000259195800055 Publication Date 2008-08-28
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Additional Links
Impact Factor 8.462 Times cited 17 Open Access
Notes Approved Most recent IF: 8.462; 2008 IF: 7.180
Call Number UA @ lucian @ Serial 4433
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Author Covaci, L.; Berciu, M.
Title Polaron formation in the presence of Rashba spin-orbit coupling: implications for spintronics Type A1 Journal article
Year 2009 Publication Physical Review Letters Abbreviated Journal Phys Rev Lett
Volume 102 Issue 18 Pages 186403
Keywords A1 Journal article
Abstract We study the effects of the Rashba spin-orbit coupling on polaron formation, using a suitable generalization of the momentum average approximation. While previous work on a parabolic band model found that spin-orbit coupling increases the effective mass, we show that the opposite holds for a tight-binding model, unless both the spin-orbit and the electron-phonon couplings are weak. It is thus possible to lower the effective mass of the polaron by increasing the spin-orbit coupling. We also show that when the spin-orbit coupling is large as compared to the phonon energy, the polaron retains only one of the spin-polarized bands in its coherent spectrum. This has major implications for the propagation of spin-polarized currents in such materials, and thus for spintronic applications.
Address Department of Physics, University of British Columbia, Vancouver, British Columbia, Canada, V6T 1Z1
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000265948600049 Publication Date 2009-05-08
Series Editor Series Title Abbreviated Series Title (down)
Series Volume Series Issue Edition
ISSN 0031-9007 ISBN Additional Links
Impact Factor 8.462 Times cited 25 Open Access
Notes Approved Most recent IF: 8.462; 2009 IF: 7.328
Call Number UA @ lucian @ Serial 4434
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