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Author Kerkhofs, S.; Leroux, F.; Allouche, L.; Mellaerts, R.; Jammaer, J.; Aerts, A.; Kirschhock, C.E.A.; Magusin, P.C.M.M.; Taulelle, F.; Bals, S.; Van Tendeloo, G.; Martens, J.A.;
  Title Single-step alcohol-free synthesis of coreshell nanoparticles of \gamma-casein micelles and silica Type A1 Journal article
  Year 2014 Publication RSC advances Abbreviated Journal Rsc Adv
  Volume 4 Issue 49 Pages 25650-25657
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract A new, single-step protocol for wrapping individual nanosized β-casein micelles with silica is presented. This biomolecule-friendly synthesis proceeds at low protein concentration at almost neutral pH, and makes use of sodium silicate instead of the common silicon alkoxides. This way, formation of potentially protein-denaturizing alcohols can be avoided. The pH of the citrate-buffered synthesis medium is close to the isoelectric point of β-casein, which favours micelle formation. A limited amount of sodium silicate is added to the protein micelle suspension, to form a thin silica coating around the β-casein micelles. The size distribution of the resulting proteinsilica structures was characterized using DLS and SAXS, as well as 1H NMR DOSY with a dedicated pulsed-field gradient cryo-probehead to cope with the low protein concentration. The degree of silica-condensation was investigated by 29Si MAS NMR, and the nanostructure was revealed by advanced electron microscopy techniques such as ESEM and HAADF-STEM. As indicated by the combined characterization results, a silica shell of 2 nm is formed around individual β-casein micelles giving rise to separate protein coresilica shell nanoparticles of 17 nm diameter. This alcohol-free method at mild temperature and pH is potentially suited for packing protein molecules into bio-compatible silica nanocapsules for a variety of applications in biosensing, therapeutic protein delivery and biocatalysis.
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  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000338434500025 Publication Date 2014-05-29
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2046-2069; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.108 Times cited 3 Open Access OpenAccess
  Notes Fwo; 262348 Esmi; 335078 Colouratom; ECAS_Sara; (ROMEO:green; preprint:; postprint:can ; pdfversion:can); Approved Most recent IF: 3.108; 2014 IF: 3.840
  Call Number UA @ lucian @ c:irua:125382 Serial 3027
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Author Leusink, D.P.; Coneri, F.; Hoek, M.; Turner, S.; Idrissi, H.; Van Tendeloo, G.; Hilgenkamp, H.
  Title Thin films of the spin ice compound Ho2Ti2O7 Type A1 Journal article
  Year 2014 Publication APL materials Abbreviated Journal Apl Mater
  Volume 2 Issue 3 Pages 032101-32107
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract The pyrochlore compounds Ho2Ti2O7 and Dy2Ti2O7 show an exotic form of magnetism called the spin ice state, resulting from the interplay between geometrical frustration and ferromagnetic coupling. A fascinating feature of this state is the appearance of magnetic monopoles as emergent excitations above the degenerate ground state. Over the past years, strong effort has been devoted to the investigation of these monopoles and other properties of the spin ice state in bulk crystals. Here, we report the fabrication of Ho2Ti2O7 thin films using pulsed laser deposition on yttria-stabilized ZrO2 substrates. We investigated the structural properties of these films by X-ray diffraction, scanning transmission electron microscopy, and atomic force microscopy, and the magnetic properties by vibrating sample magnetometry at 2 K. The films not only show a high crystalline quality, but also exhibit the hallmarks of a spin ice: a pronounced magnetic anisotropy and an intermediate plateau in the magnetization along the [111] crystal direction.
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  Language Wos 000334220300002 Publication Date 2014-03-04
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2166-532X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.335 Times cited 18 Open Access
  Notes The authors acknowledge support from the Dutch FOM and NWO foundations and from the European Union under the Framework 7 program under a contract from an Integrated Infrastructure Initiative (Reference 312483 ESTEEM2). G.V.T. acknowledges the ERC Grant N246791- COUNTATOMS. S.T. gratefully acknowledges financial support from the Fund for Scientific Research Flanders (FWO). H.I. acknowledges the IAP program of the Belgian State Federal Office for Scientific, Technical and Cultural Affairs under Contract No. P7/21. The microscope used in this study was partially financed by the Hercules Foundation of the Flemish Government. The authors acknowledge fruitful interactions with A. Brinkman, M. G. Blamire, M. Egilmez, F. J. G. Roesthuis, J. N. Beukers, C. G. Molenaar, M. Veldhorst, and X. Renshaw Wang; esteem2_ta Approved Most recent IF: 4.335; 2014 IF: NA
  Call Number UA @ lucian @ c:irua:115555 Serial 3641
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Author Goris, B.; Turner, S.; Bals, S.; Van Tendeloo, G.
  Title Three-dimensional valency mapping in ceria nanocrystals Type A1 Journal article
  Year 2014 Publication ACS nano Abbreviated Journal Acs Nano
  Volume 8 Issue 10 Pages 10878-10884
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Using electron tomography combined with electron energy loss spectroscopy (EELS), we are able to map the valency of the Ce ions in CeO2-x nanocrystals in three dimensions. Our results show a clear facet-dependent reduction shell at the surface of ceria nanoparticles; {111} surface facets show a low surface reduction, whereas at {001} surface facets, the cerium ions are more likely to be reduced over a larger surface shell. Our generic tomographic technique allows a full 3D data cube to be reconstructed, containing an EELS spectrum in each voxel. This possibility enables a three-dimensional investigation of a plethora of material-specific physical properties such as valency, chemical composition, oxygen coordination, or bond lengths, triggering the synthesis of nanomaterials with improved properties.
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  Language Wos 000343952600126 Publication Date 2014-10-06
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 13.942 Times cited 85 Open Access OpenAccess
  Notes 335078 Colouratom; 246791 Countatoms; Fwo; 312483 Esteem2; esteem2jra4; ECASSara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); Approved Most recent IF: 13.942; 2014 IF: 12.881
  Call Number UA @ lucian @ c:irua:121219 Serial 3656
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Author Heyer, S.; Janssen, W.; Turner, S.; Lu, Y.-G.; Yeap, W.S.; Verbeeck, J.; Haenen, K.; Krueger, A.
  Title Toward deep blue nano hope diamonds : heavily boron-doped diamond nanoparticles Type A1 Journal article
  Year 2014 Publication ACS nano Abbreviated Journal Acs Nano
  Volume 8 Issue 6 Pages 5757-5764
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract The production of boron-doped diamond nanoparticles enables the application of this material for a broad range of fields, such as electrochemistry, thermal management, and fundamental superconductivity research. Here we present the production of highly boron-doped diamond nanoparticles using boron-doped CVD diamond films as a starting material. In a multistep milling process followed by purification and surface oxidation we obtained diamond nanoparticles of 1060 nm with a boron content of approximately 2.3 × 1021 cm3. Aberration-corrected HRTEM reveals the presence of defects within individual diamond grains, as well as a very thin nondiamond carbon layer at the particle surface. The boron K-edge electron energy-loss near-edge fine structure demonstrates that the B atoms are tetrahedrally embedded into the diamond lattice. The boron-doped diamond nanoparticles have been used to nucleate growth of a boron-doped diamond film by CVD that does not contain an insulating seeding layer.
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  Language Wos 000338089200039 Publication Date 2014-04-09
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 13.942 Times cited 71 Open Access
  Notes the Research Foundation Flanders (FWO-Vlaanderen) (G.0555.10N;G.0568.10N; G.0456.12; G0044.13N and a postdoctoral scholarship for S.T.); EU FP7 through Marie Curie ITN “MATCON” (PITNGA-127 2009-238201)the Collaborative Project “DINAMO” (No. 245122) Integrated Infrastructure Initiative, Reference No. 312483-ESTEEM2.; esteem2_jra3 Approved Most recent IF: 13.942; 2014 IF: 12.881
  Call Number UA @ lucian @ c:irua:117599 Serial 3683
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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
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  Language English Wos 000346172100002 Publication Date 2014-04-22
  Series Editor Series Title Abbreviated Series Title
  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 Kalesaki, E.; Boneschanscher, M.P.; Geuchies, J.J.; Delerue, C.; Morais Smith, C.; Evers, W.H.; Allan, G.; Altantzis, T.; Bals, S.; Vanmaekelbergh, D.
  Title Preparation and study of 2-D semiconductors with Dirac type bands due to the honeycomb nanogeometry Type P1 Proceeding
  Year 2014 Publication Proceedings of the Society of Photo-optical Instrumentation Engineers T2 – Proceedings of SPIE Abbreviated Journal
  Volume 8981 Issue Pages 898107-898107
  Keywords P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract The interest in 2-dimensional systems with a honeycomb lattice and related Dirac-­type electronic bands has exceeded the prototype graphene1. Currently, 2-­dimensional atomic2,3 and nanoscale4-­8 systems are extensively investigated in the search for materials with novel electronic properties that can be tailored by geometry. The immediate question that arises is how to fabricate 2-­D semiconductors that have a honeycomb nanogeometry, and as a consequence of that, display a Dirac-­type band structure? Here, we show that atomically coherent honeycomb superlattices of rocksalt (PbSe, PbTe) and zincblende (CdSe, CdTe) semiconductors can be obtained by nanocrystal self-­assembly and facet-­to-­facet atomic bonding, and subsequent cation exchange. We present a extended structural analysis of atomically coherent 2-­D honeycomb structures that were recently obtained with self-assembly and facet-­to-­facet bonding9. We show that this process may in principle lead to three different types of honeycomb structures, one with a graphene type-­, and two others with a silicene-­type structure. Using TEM, electron diffraction, STM and GISAXS it is convincingly shown that the structures are from the silicene-­type. In the second part of this work, we describe the electronic structure of graphene-­type and silicene type honeycomb semiconductors. We present the results of advanced electronic structure calculations using the sp3d5s* atomistic tight-­binding method10. For simplicity, we focus on semiconductors with a simple and single conduction band for the native bulk semiconductor. When the 3-­D geometry is changed into 2-­D honeycomb, a conduction band structure transformation to two types of Dirac cones, one for S-­ and one for P-­orbitals, is observed. The width of the bands depends on the honeycomb period and the coupling between the nanocrystals. Furthermore, there is a dispersionless P-­orbital band, which also forms a landmark of the honeycomb structure. The effects of considerable intrinsic spin-­orbit coupling are briefly considered. For heavy-­element compounds such as CdTe, strong intrinsic spin-­‐orbit coupling opens a non-­trivial gap at the P-­orbital Dirac point, leading to a quantum Spin Hall effect10-­12. Our work shows that well known semiconductor crystals, known for centuries, can lead to systems with entirely new electronic properties, by the simple action of nanogeometry. It can be foreseen that such structures will play a key role in future opto-­electronic applications, provided that they can be fabricated in a straightforward way.
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  Language Wos 000336040600004 Publication Date 2014-03-07
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor Times cited 2 Open Access OpenAccess
  Notes This work has been supported by funding of the French National Research Agency [ANR, (ANR-­‐09-­‐BLAN-­‐0421-­‐01)], NWO and the Dutch organization FOM [Programs “Control over Functional Nanoparticle Solids” (FNPS) and “Designing Dirac Carriers in Semiconductors” Approved Most recent IF: NA
  Call Number c:irua:131912 Serial 4039
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Author Macke, S.; Radi, A.; Hamann-Borrero, J.E.; Verna, A.; Bluschke, M.; Brück, S.; Goering, E.; Sutarto, R.; He, F.; Cristiani, G.; Wu, M.; Benckiser, E.; Habermeier, H.-U.; Logvenov, G.; Gauquelin, N.; Botton, G.A; Kajdos, A.P.; Stemmer, S.; Sawatzky,G.A.; Haverkort, M.W.; Keimer, B.; Hinkov, V.
  Title Element Specific Monolayer Depth Profiling Type A1 Journal Article
  Year 2014 Publication Advanced Materials Abbreviated Journal Adv Mater
  Volume 26 Issue 38 Pages 6554-6559
  Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT)
  Abstract The electronic phase behavior and functionality of interfaces and surfaces in complex materials are strongly correlated to chemical composition profiles, stoichiometry and intermixing. Here a novel analysis scheme for resonant X-ray reflectivity maps is introduced to determine such profiles, which is element specific and non-destructive, and which exhibits atomic-layer resolution and a probing depth of hundreds of nanometers.
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  Language Wos 000343763200004 Publication Date 2014-08-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1521-4095 ISBN Additional Links
  Impact Factor 19.791 Times cited 34 Open Access
  Notes Approved Most recent IF: 19.791; 2014 IF: NA
  Call Number EMAT @ emat @ Serial 4541
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Author N. Gauquelin, D. G. Hawthorn, G. A. Sawatzky, R. X. Liang, D. A. Bonn, W. N. Hardy & G.A. Botton
  Title Atomic scale real-space mapping of holes in YBa2Cu3O6+δ Type A1 Journal Article
  Year 2014 Publication Nature Communications Abbreviated Journal
  Volume 5 Issue Pages 4275
  Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
  Abstract The high-temperature superconductor YBa2Cu3O6+δ consists of two main structural units—a bilayer of CuO2 planes that are central to superconductivity and a CuO2+δ chain layer. Although the functional role of the planes and chains has long been established, most probes integrate over both, which makes it difficult to distinguish the contribution of each. Here we use electron energy loss spectroscopy to directly resolve the plane and chain contributions to the electronic structure in YBa2Cu3O6 and YBa2Cu3O7. We directly probe the charge transfer of holes from the chains to the planes as a function of oxygen content, and show that the change in orbital occupation of Cu is large in the chain layer but modest in CuO2 planes, with holes in the planes doped primarily into the O 2p states. These results provide direct insight into the local electronic structure and charge transfers in this important high-temperature superconductor.
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  Language Wos 000340615100002 Publication Date 2014-07-16
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN ISBN Additional Links
  Impact Factor Times cited 22 Open Access
  Notes Approved Most recent IF: NA
  Call Number EMAT @ emat @ Serial 4542
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Author N. Gauquelin, E. Benckiser, M. K. Kinyanjui, M. Wu, Y. Lu, G. Christiani, G. Logvenov, H.-U. Habermeier, U. Kaiser, B. Keimer, and G. A. Botton
  Title Atomically resolved EELS mapping of the interfacial structure of epitaxially strained LaNiO3/LaAlO3 superlattices Type A1 Journal Article
  Year 2014 Publication Physical Review B Abbreviated Journal
  Volume 90 Issue Pages 195140
  Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
  Abstract The interfacial atomic structure of a metallic LaNiO3/LaAlO3 superlattice grown on a LaSrAlO4 substrate was

investigated using a combination of atomically resolved electron energy loss spectroscopy (EELS) at the Al K,

Al L2,3, Sr L2,3, Ni L2,3, La M4,5, and O K edges as well as hybridization mapping of selected features of the O

K-edge fine structure.We observe an additional La1−xSrxAl1−yNiyO3 layer at the substrate-superlattice interface,

possibly linked to diffusion of Al and Sr into the growing film or a surface reconstruction due to Sr segregation.

The roughness of the LaNiO3/LaAlO3 interfaces is found to be on average around one pseudocubic unit cell. The

O K-edge EELS spectra revealed reduced spectral weight of the prepeak derived from Ni-O hybridized states in

the LaNiO3 layers. We rule out oxygen nonstoichiometry of the LaNiO3 layers and discuss changes in the Ni-O

hybridization due to heterostructuring as possible origin.
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  Language Wos 000345467000003 Publication Date 2014-11-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN ISBN Additional Links
  Impact Factor Times cited 17 Open Access
  Notes Approved Most recent IF: NA
  Call Number EMAT @ emat @ Serial 4544
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Author M. K. Kinyanjui, N. Gauquelin, E. Benckiser, H. –U. Habermeier, B. Keimer, U. Kaiser and G.A. Botton
  Title Local lattice distortion and anisotropic modulation in Epitaxially Strained LaNiO3/LaAlO3 hetero-structures Type A1 Journal Article
  Year 2014 Publication Applied Physics Letters Abbreviated Journal
  Volume 104 Issue Pages 221909
  Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
  Abstract Using a complementary combination of x-ray diffraction and atomically resolved imaging we investigated the lattice structure of epitaxial LaNiO3/LaAlO3 superlattices grown on a compressive-strain inducing LaSrAlO4 (001) substrate. A refinement of the structure obtained from the x-ray data revealed the monoclinic I 2/c 1 1 space group. The (Ni/Al)O6 octahedral rotation angle perpendicular to the superlattice plane is enhanced, and the one parallel to the plane is reduced with respect to the corresponding bulk values. High-angle annular dark field imaging was used to determine the lattice parameters within the superlattice unit cell. High-resolution electron microscopy images of the oxygen atoms are consistent with the x-ray results.
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  Language Wos 000337161700029 Publication Date 2014-06-07
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN ISBN Additional Links
  Impact Factor Times cited 22 Open Access
  Notes Approved Most recent IF: NA
  Call Number EMAT @ emat @ Serial 4545
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Author Hoffman, B.M.; Lukoyanov, D.; Yang, Z.-Y.; Dean, D.R.; Seefeldt, L.C.
  Title Mechanism of Nitrogen Fixation by Nitrogenase: The Next Stage Type A1 Journal Article
  Year 2014 Publication Chemical Reviews Abbreviated Journal Chem. Rev.
  Volume 114 Issue 8 Pages 4041-4062
  Keywords A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
  Abstract Ammonia is a crucial nutrient used for plant growth and as a building block in pharmaceutical and chemical industry, produced via nitrogen fixation of the ubiquitous atmospheric N2. Current industrial ammonia production relies heavily on fossil resources, but a lot of work is put into developing non-fossil based pathways. Among these is the use of nonequilibrium plasma. In this work, we investigated water vapor as H source for nitrogen fixation into NH3 by non-equilibrium plasma. The highest selectivity towards NH3 was observed with low amounts of added H2O vapor, but the highest production rate was reached at high H2O vapor.
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  Publisher Place of Publication (down) Editor
  Language Wos Publication Date 2014-04-23
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0009-2665 ISBN Additional Links
  Impact Factor Times cited Open Access
  Notes We would like to thank Sylvia Dewilde (Department of Biomedical Sciences) for providing analytical equipment. Approved no
  Call Number PLASMANT @ plasmant @ Serial 6337
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Author García, J.H.; Uchoa, B.; Covaci, L.; Rappoport, T.G.
  Title Adatoms and Anderson localization in graphene Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 90 Issue 8 Pages 085425
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We address the nature of the disordered state that results from the adsorption of adatoms in graphene. For adatoms that sit at the center of the honeycomb plaquette, as in the case of most transition metals, we show that the ones that form a zero-energy resonant state lead to Anderson localization in the vicinity of the Dirac point. Among those, we show that there is a symmetry class of adatoms where Anderson localization is suppressed, leading to an exotic metallic state with large and rare charge droplets, that localizes only at the Dirac point. We identify the experimental conditions for the observation of the Anderson transition for adatoms in graphene.
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  Language Wos 000341238600004 Publication Date 2014-08-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 12 Open Access
  Notes ; We acknowledge F. Guinea, K. Mullen, A. H. Castro Neto, and E. Mucciolo for discussions. B. U. acknowledges the University of Oklahoma for financial support and NSF Grant No. DMR-1352604 for partial support. T.G.R. and J.H.G acknowledge Brazilian agencies CNPq, FAPERJ, and “INCT de nanoestruturas de carbono” for financial support. ; Approved Most recent IF: 3.836; 2014 IF: 3.736
  Call Number UA @ lucian @ c:irua:119258 Serial 57
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Author Becker, T.; Nelissen, K.; Cleuren, B.; Partoens, B.; Van den Broeck, C.
  Title Adsorption and desorption in confined geometries : a discrete hopping model Type A1 Journal article
  Year 2014 Publication The European physical journal. Special topics Abbreviated Journal Eur Phys J-Spec Top
  Volume 223 Issue 14 Pages 3243-3256
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We study the adsorption and desorption kinetics of interacting particles moving on a one-dimensional lattice. Confinement is introduced by limiting the number of particles on a lattice site. Adsorption and desorption are found to proceed at different rates, and are strongly influenced by the concentration-dependent transport diffusion. Analytical solutions for the transport and self-diffusion are given for systems of length 1 and 2 and for a zero-range process. In the last situation the self- and transport diffusion can be calculated analytically for any length.
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  Language Wos 000346416400015 Publication Date 2014-12-15
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1951-6355;1951-6401; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 1.862 Times cited 4 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government – department EWI. ; Approved Most recent IF: 1.862; 2014 IF: 1.399
  Call Number UA @ lucian @ c:irua:122779 Serial 61
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Author Deng, S.; Verbruggen, S.W.; He, Z.; Cott, D.J.; Vereecken, P.M.; Martens, J.A.; Bals, S.; Lenaerts, S.; Detavernier, C.
  Title Atomic layer deposition-based synthesis of photoactive TiO2 nanoparticle chains by using carbon nanotubes as sacrificial templates Type A1 Journal article
  Year 2014 Publication RSC advances Abbreviated Journal Rsc Adv
  Volume 4 Issue 23 Pages 11648-11653
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL)
  Abstract Highly ordered and self supported anatase TiO2 nanoparticle chains were fabricated by calcining conformally TiO2 coated multi-walled carbon nanotubes (MWCNTs). During annealing, the thin tubular TiO2 coating that was deposited onto the MWCNTs by atomic layer deposition (ALD) was transformed into chains of TiO2 nanoparticles ([similar]12 nm diameter) with an ultrahigh surface area (137 cm2 per cm2 of substrate), while at the same time the carbon from the MWCNTs was removed. Photocatalytic tests on the degradation of acetaldehyde proved that these forests of TiO2 nanoparticle chains are highly photoactive under UV light because of their well crystallized anatase phase.
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  Language Wos 000332470000017 Publication Date 2014-02-14
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2046-2069; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.108 Times cited 45 Open Access Not_Open_Access
  Notes ; The authors wish to thank the Research Foundation – Flanders (FWO) and UGENT-GOA-01G01513 for financial support. The authors acknowledge the European Research Council for funding under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement no. 239865-COCOON and no. 246791-COUNTATOMS. JAM acknowledges the Flemish government for long-term structural funding (Methusalem). ; Approved Most recent IF: 3.108; 2014 IF: 3.840
  Call Number UA @ lucian @ c:irua:117298 Serial 168
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Author Kundu, P.; Turner, S.; Van Aert, S.; Ravishankar, N.; Van Tendeloo, G.
  Title Atomic structure of quantum gold nanowires : quantification of the lattice strain Type A1 Journal article
  Year 2014 Publication ACS nano Abbreviated Journal Acs Nano
  Volume 8 Issue 1 Pages 599-606
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Theoretical studies exist to compute the atomic arrangement in gold nanowires and the influence on their electronic behavior with decreasing diameter. Experimental studies, e.g., by transmission electron microscopy, on chemically synthesized ultrafine wires are however lacking owing to the unavailability of suitable protocols for sample preparation and the stability of the wires under electron beam irradiation. In this work, we present an atomic scale structural investigation on quantum single crystalline gold nanowires of 2 nm diameter, chemically prepared on a carbon film grid. Using low dose aberration-corrected high resolution (S)TEM, we observe an inhomogeneous strain distribution in the crystal, largely concentrated at the twin boundaries and the surface along with the presence of facets and surface steps leading to a noncircular cross section of the wires. These structural aspects are critical inputs needed to determine their unique electronic character and their potential as a suitable catalyst material. Furthermore, electron-beam-induced structural changes at the atomic scale, having implications on their mechanical behavior and their suitability as interconnects, are discussed.
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  Language Wos 000330542900061 Publication Date 2013-11-29
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 13.942 Times cited 20 Open Access
  Notes FWO; Countatoms; Hercules Approved Most recent IF: 13.942; 2014 IF: 12.881
  Call Number UA @ lucian @ c:irua:113856 Serial 199
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Author Xu, X.; Vereecke, G.; Chen, C.; Pourtois, G.; Armini, S.; Verellen, N.; Tsai, W.K.; Kim, D.W.; Lee, E.; Lin, C.Y.; Van Dorpe, P.; Struyf, H.; Holsteyns, F.; Moshchalkov, V.; Indekeu, J.; De Gendt, S.;
  Title Capturing wetting states in nanopatterned silicon Type A1 Journal article
  Year 2014 Publication ACS nano Abbreviated Journal Acs Nano
  Volume 8 Issue 1 Pages 885-893
  Keywords A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract Spectacular progress in developing advanced Si circuits with reduced size, along the track of Moore's law, has been relying on necessary developments in wet cleaning of nanopatterned Si wafers to provide contaminant free surfaces. The most efficient cleaning is achieved when complete wetting can be realized. In this work, ordered arrays of silicon nanopillars on a hitherto unexplored small scale have been used to study the wetting behavior on nanomodulated surfaces in a substantial range of surface treatments and geometrical parameters. With the use of optical reflectance measurements, the nanoscale water imbibition depths have been measured and the transition to the superhydrophobic Cassie-Baxter state has been accurately determined. For pillars of high aspect ratio (about 15), the transition occurs even when the surface is grafted with a hydrophilic functional group. We have found a striking consistent deviation between the contact angle measurements and the straightforward application of the classical wetting models. Molecular dynamics simulations show that these deviations can be attributed to the long overlooked atomic-scale surface perturbations that are introduced during the nanofabrication process. When the transition condition is approached, transient states of partial imbibition that characterize intermediate states between the Wenzel and Cassie-Baxter states are revealed in our experiments.
  Address
  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000330542900092 Publication Date 2013-12-31
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 13.942 Times cited 39 Open Access
  Notes Approved Most recent IF: 13.942; 2014 IF: 12.881
  Call Number UA @ lucian @ c:irua:114871 Serial 276
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Author Van Holsbeke, C.S.; Verhulst, S.L.; Vos, W.G.; de Backer, J.W.; Vinchurkar, S.C.; Verdonck, P.R.; van Doorn, J.W.D.; Nadjmi, N.; de Backer, W.A.
  Title Change in upper airway geometry between upright and supine position during tidal nasal breathing Type A1 Journal article
  Year 2014 Publication Journal Of Aerosol Medicine And Pulmonary Drug Delivery Abbreviated Journal J Aerosol Med Pulm D
  Volume 27 Issue 1 Pages 51-57
  Keywords A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP); Translational Neurosciences (TNW)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000331144500007 Publication Date 2013-03-19
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1941-2711;1941-2703; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.528 Times cited 16 Open Access
  Notes ; ; Approved Most recent IF: 2.528; 2014 IF: 2.798
  Call Number UA @ lucian @ c:irua:115759 Serial 308
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Author Prodi, A.; Daoud-Aladine, A.; Gozzo, F.; Schmitt, B.; Lebedev, O.; Van Tendeloo, G.; Gilioli, E.; Bolzoni, F.; Aruga-Katori, H.; Takagi, H.; Marezio, M.; Gauzzi, A.;
  Title Commensurate structural modulation in the charge- and orbitally ordered phase of the quadruple perovskite (NaMn3)Mn4O12 Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 90 Issue 18 Pages 180101
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract By means of synchrotron x-ray and electron diffraction, we studied the structural changes at the charge order transition T-CO = 176 K in the mixed-valence quadruple perovskite (NaMn3)Mn4O12. Below T-CO we find satellite peaks indicating a commensurate structural modulation with the same propagation vector q = ( 1/2,0,-1/2) of the CE magnetic structure that orders at low temperatures, similarly to the case of simple perovskites such as La0.5Ca0.5MnO3. In the present case, the modulated structure, together with the observation of a large entropy change at T-CO, gives evidence of a rare case of full Mn3+/Mn4+ charge and orbital order, consistent with the Goodenough-Kanamori model.
  Address
  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000344915100001 Publication Date 2014-11-10
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 11 Open Access
  Notes Approved Most recent IF: 3.836; 2014 IF: 3.736
  Call Number UA @ lucian @ c:irua:122097 Serial 406
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Author Vagov, A.; Glaessl, M.; Croitoru, M.D.; Axt, V.M.; Kuhn, T.
  Title Competition between pure dephasing and photon losses in the dynamics of a dot-cavity system Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 90 Issue 7 Pages 075309
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We demonstrate that in quantum-dot cavity systems, the interplay between acoustic phonons and photon losses introduces novel features and characteristic dependencies in the system dynamics. In particular, the combined action of both dephasing mechanisms strongly affects the transition from the weak-to the strong-coupling regime as well as the shape of the spectral triplet that represents the quantum-dot occupation in Fourier space. The width of the central peak in the triplet is expected to decrease with rising temperature, while the widths and heights of the side peaks depend nonmonotonically on the dot-cavity coupling.
  Address
  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000341258700002 Publication Date 2014-08-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 11 Open Access
  Notes ; We acknowledge fruitful discussions with A. Nazir which helped us to more clearly formulate the relation between our phenomenological approach and the microscopic theory. M.D.C. further acknowledges Alexander von Humboldt and BELSPO grants for support. Financial support from the Deutsche Forschungsgemeinschaft (Grant No. AX 17/7-1) is also gratefully acknowledged. ; Approved Most recent IF: 3.836; 2014 IF: 3.736
  Call Number UA @ lucian @ c:irua:119257 Serial 437
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Author Morozov, V.A.; Raskina, M.V.; Lazoryak, B.I.; Meert, K.W.; Korthout, K.; Smet, P.F.; Poelman, D.; Gauquelin, N.; Verbeeck, J.; Abakumov, A.M.; Hadermann, J.;
  Title Crystal Structure and Luminescent Properties of R2-xEux(MoO4)(3) (R = Gd, Sm) Red Phosphors Type A1 Journal article
  Year 2014 Publication Chemistry of materials Abbreviated Journal Chem Mater
  Volume 26 Issue 24 Pages 7124-7136
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The R-2(MoO4)(3) (R = rare earth elements) molybdates doped with Eu3+ cations are interesting red-emitting materials for display and solid-state lighting applications. The structure and luminescent properties of the R2-xEux(MoO4)(3) (R = Gd, Sm) solid solutions have been investigated as a function of chemical composition and preparation conditions. Monoclinic (alpha) and orthorhombic (beta') R2-xEux(MoO4)(3) (R = Gd, Sm; 0 <= x <= 2) modifications were prepared by solid-state reaction, and their structures were investigated using synchrotron powder X-ray diffraction and transmission electron microscopy. The pure orthorhombic beta'-phases could be synthesized only by quenching from high temperature to room temperature for Gd2-xEux(MoO4)(3) in the Eu3+-rich part (x > 1) and for all Sm2-xEux(MoO4)(3) solid solutions. The transformation from the alpha-phase to the beta'-phase results in a notable increase (similar to 24%) of the unit cell volume for all R2-xEux(MoO4)(3) (R = Sm, Gd) solid solutions. The luminescent properties of all R2-xEux(MoO4)(3) (R = Gd, Sm; 0 <= x <= 2) solid solutions were measured, and their optical properties were related to their structural properties. All R2-xEux(MoO4)(3) (R = Gd, Sm; 0 <= x <= 2) phosphors emit intense red light dominated by the D-5(0)-> F-7(2) transition at similar to 616 nm. However, a change in the multiplet splitting is observed when switching from the monoclinic to the orthorhombic structure, as a consequence of the change in coordination polyhedron of the luminescent ion from RO8 to RO7 for the alpha- and beta'-modification, respectively. The Gd2-xEux(MoO4)(3) solid solutions are the most efficient emitters in the range of 0 < x < 1.5, but their emission intensity is comparable to or even significantly lower than that of Sm2-xEux(MoO4)(3) for higher Eu3+ concentrations (1.5 <= x <= 1.75). Electron energy loss spectroscopy (EELS) measurements revealed the influence of the structure and element content on the number and positions of bands in the ultraviolet-visible-infrared regions of the EELS spectrum.
  Address
  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000347139700027 Publication Date 2014-11-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 9.466 Times cited 24 Open Access
  Notes Fwo G039211n; G004413n; 278510 Vortex ECASJO_; Approved Most recent IF: 9.466; 2014 IF: 8.354
  Call Number UA @ lucian @ c:irua:122829UA @ admin @ c:irua:122829 Serial 558
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Author Çakir, D.; Peeters, F.M.
  Title Dependence of the electronic and transport properties of metal-MoSe2 interfaces on contact structures Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 89 Issue 24 Pages 245403
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Transition metal dichalcogenides (TMDs) are considered as promising candidates for next generation of electronic and optoelectronic devices. To make use of these materials, for instance in field effect transistor applications, it is mandatory to know the detailed properties of contacts of such TMDs with metal electrodes. Here, we investigate the role of the contact structure on the electronic and transport properties of metal-MoSe2 interfaces. Two different contact types, namely face and edge contacts, are studied. We consider both low (Sc) and high (Au) work function metals in order to thoroughly elucidate the role of the metal work function and the type of metal. First principles plane wave calculations and transport calculations based on nonequilibrium Green's function formalism reveal that the contact type has a large impact on the electronic and transport properties of metal-MoSe2 interfaces. For the Sc electrode, the Schottky barrier heights are around 0.25 eV for face contact and bigger than 0.6 eV for edge contact. For the Au case, we calculate very similar barrier heights for both contact types with an average value of 0.5 eV. Furthermore, while the face contact is found to be highly advantageous as compared to the edge contact for the Sc electrode, the latter contact becomes a better choice for the Au electrode. Our findings provide guidelines for the fabrication of TMD-based devices.
  Address
  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000336917700004 Publication Date 2014-06-04
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 39 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. D. C. is supported by a FWO Pegasus-short Marie Curie Fellowship. ; Approved Most recent IF: 3.836; 2014 IF: 3.736
  Call Number UA @ lucian @ c:irua:117750 Serial 644
Permanent link to this record
 

 
Author Huygh, S.; Bogaerts, A.; van Duin, A.C.T.; Neyts, E.C.
  Title Development of a ReaxFF reactive force field for intrinsic point defects in titanium dioxide Type A1 Journal article
  Year 2014 Publication Computational materials science Abbreviated Journal Comp Mater Sci
  Volume 95 Issue Pages 579-591
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract A reactive ReaxFF force field is developed for studying the influence of intrinsic point defects on the chemistry with TiO2 condensed phases. The force field parameters are optimized to ab initio data for the equations of state, relative phase stabilities for titanium and titanium dioxide, potential energy differences for (TiO2)n-clusters (n = 116). Also data for intrinsic point defects in anatase were added. These data contain formation energies for interstitial titanium and oxygen vacancies, diffusion barriers of the oxygen vacancies and molecular oxygen adsorption on a reduced anatase (101) surface. Employing the resulting force field, we study the influence of concentration of oxygen vacancies and expansion or compression of an anatase surface on the diffusion of the oxygen vacancies. Also the barrier for oxygen diffusion in the subsurface region is evaluated using this force field. This diffusion barrier of 27.7 kcal/mol indicates that the lateral redistribution of oxygen vacancies on the surface and in the subsurface will be dominated by their diffusion in the subsurface, since both this barrier as well as the barriers for diffusion from the surface to the subsurface and vice versa (17.07 kcal/mol and 21.91 kcal/mol, respectively, as calculated with DFT), are significantly lower than for diffusion on the surface (61.12 kcal/mol as calculated with DFT).
  Address
  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000343781700077 Publication Date 2014-09-16
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0927-0256; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.292 Times cited 15 Open Access
  Notes Approved Most recent IF: 2.292; 2014 IF: 2.131
  Call Number UA @ lucian @ c:irua:119409 Serial 682
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Author Berdiyorov, G.; Harrabi, K.; Oktasendra, F.; Gasmi, K.; Mansour, A.I.; Maneval, J.P.; Peeters, F.M.
  Title Dynamics of current-driven phase-slip centers in superconducting strips Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 90 Issue 5 Pages 054506
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Phase-slip centers/lines and hot spots are the main mechanisms for dissipation in current-carrying superconducting thin films. The pulsed-current method has recently been shown to be an effective tool in studying the dynamics of phase-slip centers and their evolution to hot spots. We use the time-dependent Ginzburg-Landau theory in the study of the dynamics of the superconducting condensate in superconducting strips under external current and zero external magnetic field. We show that both the flux-flow state (i.e., slow-moving vortices) and the phase-slip line state (i.e., fast-moving vortices) are dynamically stable dissipative units with temperature smaller than the critical one, whereas hot spots, which are localized normal regions where the local temperature exceeds the critical value, expand in time, resulting ultimately in a complete destruction of the condensate. The response time of the system to abrupt switching on of the overcritical current decreases with increasing both the value of the current (at all temperatures) and temperature (for a given value of the applied current). Our results are in good qualitative agreement with experiments we have conducted on Nb thin strips.
  Address
  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000344656700003 Publication Date 2014-08-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 42 Open Access
  Notes ; This work was supported by EU Marie Curie Project No. 253057, the Flemish Science Foundation (FWO-Vl), and King Fahd University of Petroleum and Minerals, Saudi Arabia, under the IN131034 DSR project. ; Approved Most recent IF: 3.836; 2014 IF: 3.736
  Call Number UA @ lucian @ c:irua:121229 Serial 775
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Author Govaerts, K.; Park, K.; De Beule, C.; Partoens, B.; Lamoen, D.
  Title Effect of Bi bilayers on the topological states of Bi2Se3 : a first-principles study Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 90 Issue 15 Pages 155124
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
  Abstract Bi2Se3 is a three-dimensional topological insulator which has been extensively studied because it has a single Dirac cone on the surface, inside a relatively large bulk band gap. However, the effect of two-dimensional topological insulator Bi bilayers on the properties of Bi2Se3 and vice versa, has not been explored much. Bi bilayers are often present between the quintuple layers of Bi2Se3, since (Bi2)n(Bi2Se3)m form stable ground-state structures. Moreover, Bi2Se3 is a good substrate for growing ultrathin Bi bilayers. By first-principles techniques, we first show that there is no preferable surface termination by either Bi or Se. Next, we investigate the electronic structure of Bi bilayers on top of, or inside a Bi2Se3 slab. If the Bi bilayers are on top, we observe a charge transfer to the quintuple layers that increases the binding energy of the surface Dirac cones. The extra states, originating from the Bi bilayers, were declared to form a topological Dirac cone, but here we show that these are ordinary Rashba-split states. This result, together with the appearance of a new Dirac cone that is localized slightly deeper, might necessitate the reinterpretation of several experimental results. When the Bi bilayers are located inside the Bi2Se3 slab, they tend to split the slab into two topological insulators with clear surface states. Interface states can also be observed, but an energy gap persists because of strong coupling between the neighboring quintuple layers and the Bi bilayers.
  Address
  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000343773200001 Publication Date 2014-10-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 30 Open Access
  Notes ; We gratefully acknowledge financial support from the Research Foundation – Flanders (FWO-Vlaanderen). K.G. thanks the University of Antwerp for a Ph.D. fellowship. C.D.B. is an aspirant of the Flemish Science Foundation. This work was carried out using the HPC infrastructure at the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, supported financially by the Hercules Foundation and the Flemish Government (EWI Department). K.P. was supported by U.S. National Science Foundation Grant No. DMR-1206354. ; Approved Most recent IF: 3.836; 2014 IF: 3.736
  Call Number UA @ lucian @ c:irua:119527 Serial 800
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Author Zhang, S.H.; Xu, W.; Peeters, F.M.; Badalyan, S.M.
  Title Electron energy and temperature relaxation in graphene on a piezoelectric substrate Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 89 Issue 19 Pages 195409
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We study the energy and temperature relaxation of electrons in graphene on a piezoelectric substrate. Scattering from the combined potential of extrinsic piezoelectric surface acoustical (PA) phonons of the substrate and intrinsic deformation acoustical phonons of graphene is considered for a (non) degenerate gas of Dirac fermions. It is shown that in the regime of low energies or temperatures the PA phonons dominate the relaxation and change qualitatively its character. This prediction is relevant for quantum metrology and electronic applications using graphene devices and suggests an experimental setup for probing electron-phonon coupling in graphene.
  Address
  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000336000400008 Publication Date 2014-05-09
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 18 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program of the Flemish government. ; Approved Most recent IF: 3.836; 2014 IF: 3.736
  Call Number UA @ lucian @ c:irua:117675 Serial 928
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Author Meert, K.W.; Morozov, V.A.; Abakumov, A.M.; Hadermann, J.; Poelman, D.; Smet, P.F.
  Title Energy transfer in Eu3+ doped scheelites : use as thermographic phosphor Type A1 Journal article
  Year 2014 Publication Optics express Abbreviated Journal Opt Express
  Volume 22 Issue 9 Pages A961-A972
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract In this paper the luminescence of the scheelite-based CaGd2(1-x)Eu2x(WO4)4 solid solutions is investigated as a function of the Eu content and temperature. All phosphors show intense red luminescence due to the 5D0 7F2 transition in Eu3+, along with other transitions from the 5D1 and 5D0 excited states. For high Eu3+ concentrations the intensity ratio of the emission originating from the 5D1 and 5D0 levels has a non-conventional temperature dependence, which could be explained by a phonon-assisted cross-relaxation process. It is demonstrated that this intensity ratio can be used as a measure of temperature with high spatial resolution, allowing the use of these scheelites as thermographic phosphor. The main disadvantage of many thermographic phosphors, a decreasing signal for increasing temperature, is absent.
  Address
  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000335905300037 Publication Date 2014-04-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1094-4087; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.307 Times cited 47 Open Access
  Notes Approved Most recent IF: 3.307; 2014 IF: 3.488
  Call Number UA @ lucian @ c:irua:117067 Serial 1044
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Author Çakir, D.; Sevik, C.; Peeters, F.M.
  Title Engineering electronic properties of metal-MoSe2 interfaces using self-assembled monolayers Type A1 Journal article
  Year 2014 Publication Journal of materials chemistry C : materials for optical and electronic devices Abbreviated Journal J Mater Chem C
  Volume 2 Issue 46 Pages 9842-9849
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Metallic contacts are critical components of electronic devices and the presence of a large Schottky barrier is detrimental for an optimal device operation. Here, we show by using first-principles calculations that a self-assembled monolayer (SAM) of polar molecules between the metal electrode and MoSe2 monolayer is able to convert the Schottky contact into an almost Ohmic contact. We choose -CH3 and -CF3 terminated short-chain alkylthiolate (i.e. SCH3 and fluorinated alkylthiolates (SCF3)) based SAMs to test our approach. We consider both high (Au) and low (Sc) work function metals in order to thoroughly elucidate the role of the metal work function. In the case of Sc, the Fermi level even moves into the conduction band of the MoSe2 monolayer upon SAM insertion between the metal surface and the MoSe2 monolayer, and hence possibly switches the contact type from Schottky to Ohmic. The usual Fermi level pinning at the metal-transition metal dichalcogenide (TMD) contact is shown to be completely removed upon the deposition of a SAM. Systematic analysis indicates that the work function of the metal surface and the energy level alignment between the metal electrode and the TMD monolayer can be tuned significantly by using SAMs as a buffer layer. These results clearly indicate the vast potential of the proposed interface engineering to modify the physical and chemical properties of MoSe2.
  Address
  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000344998700007 Publication Date 2014-10-16
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2050-7526;2050-7534; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 5.256 Times cited 22 Open Access
  Notes ; Part of this work is supported by the Flemish Science Foundation (FWO-VI) and the Methusalem foundation of the Flemish Government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). D. C. is supported by a FWO Pegasus-short Marie Curie Fellowship. C. S. acknowledges the support from Scientific and Technological Research Council of Turkey (TUBITAK 113F096), Anadolu University (BAP-1306F281, -1404F158) and Turkish Academy of Science (TUBA). ; Approved Most recent IF: 5.256; 2014 IF: 4.696
  Call Number UA @ lucian @ c:irua:122157 Serial 1046
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Author Damm, H.; Adriaensens, P.; De Dobbelaere, C.; Capon, B.; Elen, K.; Drijkoningen, J.; Conings, B.; Manca, J.V.; D’Haen, J.; Detavernier, C.; Magusin, P.C.M.M.; Hadermann, J.; Hardy, A.; Van Bael, M.K.;
  Title Factors Influencing the Conductivity of Aqueous Sol(ution)-Gel-Processed Al-Doped ZnO Films Type A1 Journal article
  Year 2014 Publication Chemistry of materials Abbreviated Journal Chem Mater
  Volume 26 Issue 20 Pages 5839-5851
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000343950300004 Publication Date 2014-10-06
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0897-4756;1520-5002; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 9.466 Times cited 24 Open Access
  Notes Approved Most recent IF: 9.466; 2014 IF: 8.354
  Call Number UA @ lucian @ c:irua:121211 Serial 1170
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Author Rehor, I.; Mackova, H.; Filippov, S.K.; Kucka, J.; Proks, V.; Slegerova, J.; Turner, S.; Van Tendeloo, G.; Ledvina, M.; Hruby, M.; Cigler, P.;
  Title Fluorescent nanodiamonds with bioorthogonally reactive protein-resistant polymeric coatings Type A1 Journal article
  Year 2014 Publication ChemPlusChem Abbreviated Journal Chempluschem
  Volume 79 Issue 1 Pages 21-24
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The novel synthesis of a polymeric interface grown from the surface of bright fluorescent nanodiamonds is reported. The polymer enables bioorthogonal attachment of various molecules by click chemistry; the particles are resistant to nonspecific protein adsorption and show outstanding colloidal stability in buffers and biological media. The coating fully preserves the unique optical properties of the nitrogen-vacancy centers that are crucial for bioimaging and sensoric applications.
  Address
  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000337974900002 Publication Date 2013-12-11
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2192-6506; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.797 Times cited 34 Open Access
  Notes EU 7FP Program (no.262348); European Soft Matter Infrastructure; ESMI; ERC (grant no.246791)-COUNTATOMS; FWO Approved Most recent IF: 2.797; 2014 IF: 2.997
  Call Number UA @ lucian @ c:irua:113088 Serial 1235
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Author Horzum, S.; Çakir, D.; Suh, J.; Tongay, S.; Huang, Y.-S.; Ho, C.-H.; Wu, J.; Sahin, H.; Peeters, F.M.
  Title Formation and stability of point defects in monolayer rhenium disulfide Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 89 Issue 15 Pages 155433
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Recently, rhenium disulfide (ReS2) monolayers were experimentally extracted by conventional mechanical exfoliation technique from as-grown ReS2 crystals. Unlike the well-known members of transition metal dichalcogenides (TMDs), ReS2 crystallizes in a stable distorted-1T structure and lacks an indirect to direct gap crossover. Here we present an experimental and theoretical study of the formation, energetics, and stability of the most prominent lattice defects in monolayer ReS2. Experimentally, irradiation with 3-MeV He+2 ions was used to break the strong covalent bonds in ReS2 flakes. Photoluminescence measurements showed that the luminescence from monolayers is mostly unchanged after highly energetic a particle irradiation. In order to understand the energetics of possible vacancies in ReS2 we performed systematic first-principles calculations. Our calculations revealed that the formation of a single sulfur vacancy has the lowest formation energy in both Re and S rich conditions and a random distribution of such defects are energetically more preferable. Sulfur point defects do not result in any spin polarization whereas the creation of Re-containing point defects induce magnetization with a net magnetic moment of 1-3 mu B. Experimentally observed easy formation of sulfur vacancies is in good agreement with first-principles calculations.
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  Corporate Author Thesis
  Publisher Place of Publication (down) Editor
  Language Wos 000337301200009 Publication Date 2014-04-28
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 130 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the bilateral project FWO-TUBITAK, and the Methusalem Foundation of the Flemish government. Computational resources were provided by TUBITAK ULAK-BIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H. S. was supported by a FWO Pegasus Long Marie Curie Fellowship. D. C. was supported by a FWO Pegasus-short Marie Curie Fellowship. ; Approved Most recent IF: 3.836; 2014 IF: 3.736
  Call Number UA @ lucian @ c:irua:118410 Serial 1250
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