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Author Dubrovinsky, L.; Dubrovinskaia, N.; Prakapenka, V.B.; Abakumov, A.M.
  Title Implementation of micro-ball nanodiamond anvils for high-pressure studies above 6 Mbar Type A1 Journal article
  Year (down) 2012 Publication Nature communications Abbreviated Journal Nat Commun
  Volume 3 Issue Pages 1163-1167
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Since invention of the diamond anvil cell technique in the late 1950s for studying materials at extreme conditions, the maximum static pressure generated so far at room temperature was reported to be about 400 GPa. Here we show that use of micro-semi-balls made of nanodiamond as second-stage anvils in conventional diamond anvil cells drastically extends the achievable pressure range in static compression experiments to above 600 GPa. Micro-anvils (10-50 mu m in diameter) of superhard nano-diamond (with a grain size below similar to 50 nm) were synthesized in a large volume press using a newly developed technique. In our pilot experiments on rhenium and gold we have studied the equation of state of rhenium at pressures up to 640 GPa and demonstrated the feasibility and crucial necessity of the in situ ultra high-pressure measurements for accurate determination of material properties at extreme conditions.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000313514100073 Publication Date 2012-10-23
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2041-1723; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 12.124 Times cited 150 Open Access
  Notes Approved Most recent IF: 12.124; 2012 IF: 10.015
  Call Number UA @ lucian @ c:irua:110134 Serial 1563
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Author Beheshtian, J.; Sadeghi, A.; Neek-Amal, M.; Michel, K.H.; Peeters, F.M.
  Title Induced polarization and electronic properties of carbon-doped boron nitride nanoribbons Type A1 Journal article
  Year (down) 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 86 Issue 19 Pages 195433-195438
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The electronic properties of boron nitride nanoribbons (BNNRs) doped with a line of carbon atoms are investigated using density functional calculations. By replacing a line of alternating B and N atoms with carbons, three different configurations are possible depending on the type of the atoms which bond to the carbons. We found very different electronic properties for these configurations: (i) the NCB arrangement is strongly polarized with a large dipole moment having an unexpected direction, (ii) the BCB and NCN arrangements are nonpolar with zero dipole moment, (iii) the doping by a carbon line reduces the band gap regardless of the local arrangement of the borons and the nitrogens around the carbon line, and (iv) the polarization and energy gap of the carbon-doped BNNRs can be tuned by an electric field applied parallel to the carbon line. Similar effects were found when either an armchair or zigzag line of carbon was introduced.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000311694200006 Publication Date 2012-11-29
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 41 Open Access
  Notes ; We would like to thank J. M. Pereira and S. Goedecker for helpful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the ESF-EuroGRAPHENE project CONGRAN. M. N.-A is supported by EU-Marie Curie IIF postdoc Fellowship/299522. ; Approved Most recent IF: 3.836; 2012 IF: 3.767
  Call Number UA @ lucian @ c:irua:105136 Serial 1603
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Author Silhanek, A.V.; Leo, A.; Grimaldi, G.; Berdiyorov, G.R.; Milošević, M.V.; Nigro, A.; Pace, S.; Verellen, N.; Gillijns, W.; Metlushko, V.; Ilić, B.; Zhu, X.; Moshchalkov, V.V.;
  Title Influence of artificial pinning on vortex lattice instability in superconducting films Type A1 Journal article
  Year (down) 2012 Publication New journal of physics Abbreviated Journal New J Phys
  Volume 14 Issue Pages 053006-053006,11
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract In superconducting films under an applied dc current, we analyze experimentally and theoretically the influence of engineered pinning on the vortex velocity at which the flux-flow dissipation undergoes an abrupt transition from low to high resistance. We argue, based on a nonuniform distribution of vortex velocity in the sample, that in strongly disordered systems the mean critical vortex velocity for flux-flow instability (i) has a nonmonotonic dependence on magnetic field and (ii) decreases as the pinning strength is increased. These findings challenge the generally accepted microscopic model of Larkin and Ovchinnikov (1979 J. Low. Temp. Phys. 34 409) and all subsequent refinements of this model which ignore the presence of pinning centers.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Bristol Editor
  Language Wos 000304871700003 Publication Date 2012-05-04
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1367-2630; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.786 Times cited 40 Open Access
  Notes ; This work was supported by the Methusalem Funding of the Flemish Government, the ESF-NES program, the Belgian Science Policy (IAP) and the Fund for Scientific Research-Flanders (FWO-Vlaanderen). AVS, GRB and WG received individual support from FWO-Vlaanderen. GG acknowledges support from the research project L.R. N5 of Regione Campania. VM acknowledges financial support from the US NSF, grant no. ECCS-0823813. We acknowledge J Van de Vondel for a critical reading of the manuscript. ; Approved Most recent IF: 3.786; 2012 IF: 4.063
  Call Number UA @ lucian @ c:irua:98949 Serial 1616
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Author Chen, Y.Y.; Pourtois, G.; Adelmann, C.; Goux, L.; Govoreanu, B.; Degreave, R.; Jurczak, M.; Kittl, J.A.; Groeseneken, G.; Wouters, D.J.
  Title Insights into Ni-filament formation in unipolar-switching Ni/HfO2/TiN resistive random access memory device Type A1 Journal article
  Year (down) 2012 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
  Volume 100 Issue 11 Pages 113513-113513,4
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract In this letter, CMOS-compatible Ni/HfO2/TiN resistive random access memory stacks demonstrated attractive unipolar switching properties, showing >10(3) endurance and long retention at 150 degrees C. The Ni bottom electrode (BE) improved the switching yield over the NiSiPt BE. To better understand the unipolar forming mechanism, ab initio simulation and time of flight-secondary ion mass spectroscopy were utilized. Compared to the NiSiPt BE, Ni BE gives larger Ni diffusion in the HfO2 and lower formation enthalpy of Ni2+ species during electrical forming. Both the electrical and physical results supported a Ni-injection mechanism for the filament formation. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3695078]
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000302204900091 Publication Date 2012-03-17
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.411 Times cited 29 Open Access
  Notes Approved Most recent IF: 3.411; 2012 IF: 3.794
  Call Number UA @ lucian @ c:irua:98295 Serial 1674
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Author Varykhalov, A.; Marchenko, D.; Sanchez-Barriga, J.; Scholz, M.R.; Verberck, B.; Trauzettel, B.; Wehling, T.O.; Carbone, C.; Rader, O.
  Title Intact dirac cones at broken sublattice symmetry : photoemission study of graphene on Ni and Co Type A1 Journal article
  Year (down) 2012 Publication Physical review X Abbreviated Journal Phys Rev X
  Volume 2 Issue 4 Pages 041017-10
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The appearance of massless Dirac fermions in graphene requires two equivalent carbon sublattices of trigonal shape. While the generation of an effective mass and a band gap at the Dirac point remains an unresolved problem for freestanding extended graphene, it is well established by breaking translational symmetry by confinement and by breaking sublattice symmetry by interaction with a substrate. One of the strongest sublattice-symmetry-breaking interactions with predicted and measured band gaps ranging from 400 meV to more than 3 eV has been attributed to the interfaces of graphene with Ni and Co, which are also promising spin-filter interfaces. Here, we apply angle-resolved photoemission to epitaxial graphene on Ni (111) and Co(0001) to show the presence of intact Dirac cones 2.8 eV below the Fermi level. Our results challenge the common belief that the breaking of sublattice symmetry by a substrate and the opening of the band gap at the Dirac energy are in a straightforward relation. A simple effective model of a biased bilayer structure composed of graphene and a sublattice-symmetry-broken layer, corroborated by density-functional-theory calculations, demonstrates the general validity of our conclusions.
  Address
  Corporate Author Thesis
  Publisher Place of Publication College Park, Md Editor
  Language Wos 000312703200001 Publication Date 2012-12-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2160-3308; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 12.789 Times cited 86 Open Access
  Notes ; A. V. acknowledges helpful discussions with N. Sandler. This work was supported by SPP 1459 of the Deutsche Forschungsgemeinschaft. B. V. acknowledges support from the Research Foundation Flanders (FWO-Vlaanderen). B. T. and T. O. W. would like to thank the KITP at Santa Barbara for hospitality during the completion of this work. ; Approved Most recent IF: 12.789; 2012 IF: 6.711
  Call Number UA @ lucian @ c:irua:105964 Serial 1677
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Author Grujić, M.; Zarenia, M.; Tadić, M.; Peeters, F.M.
  Title Interband optical absorption in a circular graphene quantum dot Type A1 Journal article
  Year (down) 2012 Publication Physica scripta Abbreviated Journal Phys Scripta
  Volume T149 Issue Pages 014056-014056,4
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We investigate the energy levels and optical properties of a circular graphene quantum dot in the presence of an external magnetic field perpendicular to the dot. Based on the Dirac-Weyl equation and assuming zero outward current at the edge of the dot we present the results for two different types of boundary conditions, i.e. infinite-mass (IMBC) and zigzag boundary conditions. We found that the dot with zigzag edges displays a zero-energy state in the energy spectra while this is not the case for the IMBCs. For both boundary conditions, the confinement becomes dominated by the magnetic field, where the energy levels converge to the Landau levels as the magnetic field increases. The effect of boundary conditions on the electron-and hole-energy states is found to affect the interband absorption spectra, where we found larger absorption in the case of IMBCs. The selection rules for interband optical transitions are determined and discussed for both boundary conditions.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Stockholm Editor
  Language Wos 000303523500057 Publication Date 2012-04-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0031-8949;1402-4896; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 1.28 Times cited 5 Open Access
  Notes ; This work was supported by the EuroGraphene program of the ESF (project CONGRAN), the Ministry of Education and Science of Serbia, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 1.28; 2012 IF: 1.032
  Call Number UA @ lucian @ c:irua:99136 Serial 1688
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Author Berdiyorov, G.R.; Milošević, M.V.; Latimer, M.L.; Xiao, Z.L.; Kwok, W.K.; Peeters, F.M.
  Title Large magnetoresistance oscillations in mesoscopic superconductors due to current-excited moving vortices Type A1 Journal article
  Year (down) 2012 Publication Physical review letters Abbreviated Journal Phys Rev Lett
  Volume 109 Issue 5 Pages 057004
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We show in the case of a superconducting Nb ladder that a mesoscopic superconductor typically exhibits magnetoresistance oscillations whose amplitude and temperature dependence are different from those stemming from the Little-Parks effect. We demonstrate that these large resistance oscillations (as well as the monotonic background on which they are superimposed) are due to current-excited moving vortices, where the applied current in competition with the oscillating Meissner currents imposes or removes the barriers for vortex motion in an increasing magnetic field. Because of the ever present current in transport measurements, this effect should be considered in parallel with the Little-Parks effect in low-critical temperature (T-c) samples, as well as with recently proposed thermal activation of dissipative vortex-antivortex pairs in high-T-c samples.
  Address
  Corporate Author Thesis
  Publisher Place of Publication New York, N.Y. Editor
  Language Wos 000306994900024 Publication Date 2012-07-31
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 8.462 Times cited 65 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP) (theory) and by the U. S. Department of Energy (DOE) Award No. DE-FG02-06ER46334 (experiment). G. R. B. acknowledges individual grant from FWO-Vl. W. K. K. acknowledges support from DOE BES under Contract No. DE-AC02-06CH11357, which also funds Argonne's Center for Nanoscale Materials (CNM) where the focused-ion-beam milling was performed. ; Approved Most recent IF: 8.462; 2012 IF: 7.943
  Call Number UA @ lucian @ c:irua:100832 Serial 1780
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Author Dachraoui, W.; Hadermann, J.; Abakumov, A.M.; Tsirlin, A.A.; Batuk, D.; Glazyrin, K.; McCammon, C.; Dubrovinsky, L.; Van Tendeloo, G.
  Title Local oxygen-vacancy ordering and twinned octahedral tilting pattern in the Bi0.81Pb0.19FeO2.905 cubic perovskite Type A1 Journal article
  Year (down) 2012 Publication Chemistry of materials Abbreviated Journal Chem Mater
  Volume 24 Issue 7 Pages 1378-1385
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The structure of Bi0.81Pb0.19FeO2.905 was investigated on different length scales using a combination of electron diffraction, high-resolution scanning transmission electron microscopy, synchrotron X-ray powder diffraction, and Mössbauer spectroscopy. In the 80300 K temperature range, the average crystal structure of Bi0.81Pb0.19FeO2.905 is a cubic Pm3̅m perovskite with a = 3.95368(3) Å at T = 300 K. The (Pb2+, Bi3+) cations and O2 anions are randomly displaced along the 110 cubic directions, indicating the steric activity of the lone pair on the Pb2+ and Bi3+ cations and a tilting distortion of the perovskite framework. The charge imbalance induced by the heterovalent Bi3+ → Pb2+ substitution is compensated by the formation of oxygen vacancies preserving the trivalent state of the Fe cations. On a short scale, oxygen vacancies are located in anion-deficient (FeO1.25) layers that are approximately 6 perovskite unit cells apart and transform every sixth layer of the FeO6 octahedra into a layer with a 1:1 mixture of corner-sharing FeO4 tetrahedra and FeO5 tetragonal pyramids. The anion-deficient layers act as twin planes for the octahedral tilting pattern of adjacent perovskite blocks. They effectively randomize the octahedral tilting and prevent the cooperative distortion of the perovskite framework. The disorder in the anion sublattice impedes cooperative interactions of the local dipoles induced by the off-center displacements of the Pb and Bi cations. Magnetic susceptibility measurements evidence the antiferromagnetic ordering in Bi0.81Pb0.19FeO2.905 at low temperatures.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Washington, D.C. Editor
  Language Wos 000302487500018 Publication Date 2012-03-13
  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 27 Open Access
  Notes Approved Most recent IF: 9.466; 2012 IF: 8.238
  Call Number UA @ lucian @ c:irua:97389 Serial 1829
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Author Tikhomirov, V.K.; Vosch, T.; Fron, E.; Rodríguez, V.D.; Velázquez, J.J.; Kirilenko, D.; Van Tendeloo, G.; Hofkens, J.; Van der Auweraer, M.; Moshchalkov, V.V.
  Title Luminescence of oxyfluoride glasses co-doped with Ag nanoclusters and Yb3+ ions Type A1 Journal article
  Year (down) 2012 Publication RSC advances Abbreviated Journal Rsc Adv
  Volume 2 Issue 4 Pages 1496-1501
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Bulk oxyfluoride glasses co-doped with Ag nanoclusters and Yb3+ ions have been prepared by a melt quenching technique. When excited in the absorption band of the Ag nanoclusters between 300 to 500 nm, these glasses emit a broad band characteristic of the Ag nanoclusters between 400 to 750 nm as well as an emission band between 900 to 1100 nm, originating from Yb3+ ions. The intensity ratio of the Yb3+/Ag emission bands increases with the Ag doping level at a fixed concentration of Yb3+, indicating the presence of energy transfer mechanism from the Ag nanoclusters to the Yb3+ ions. Comparison of time-resolved decay kinetics of the luminescence in the respectively Ag nanocluster-Yb3+ co-doped and single Ag nanocluster doped glasses, hints towards an energy transfer from the red and infrared emitting Ag nanoclusters to the Yb3+ ions.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000299695300038 Publication Date 2011-12-19
  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 46 Open Access
  Notes Fwo; Iap Approved Most recent IF: 3.108; 2012 IF: 2.562
  Call Number UA @ lucian @ c:irua:96239 Serial 1856
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Author Brück, S.; Paul, M.; Tian, H.; Müller, A.; Kufer, D.; Praetorius, C.; Fauth, K.; Audehm, P.; Goering, E.; Verbeeck, J.; Van Tendeloo, G.; Sing, M.; Claessen, R.;
  Title Magnetic and electronic properties of the interface between half metallic Fe3O4 and semiconducting ZnO Type A1 Journal article
  Year (down) 2012 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
  Volume 100 Issue 8 Pages 081603-081603,4
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract We have investigated the magnetic depth profile of an epitaxial Fe3O4 thin film grown directly on a semiconducting ZnO substrate by soft x-ray resonant magnetic reflectometry (XRMR) and electron energy loss spectroscopy (EELS). Consistent chemical profiles at the interface between ZnO and Fe3O4 are found from both methods. Valence selective EELS and XRMR reveal independently that the first monolayer of Fe at the interface between ZnO and Fe3O4 contains only Fe3+ ions. Besides this narrow 2.5 Å interface layer, Fe3O4 shows magnetic bulk properties throughout the whole film making highly efficient spin injection in this system feasible.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000300711200014 Publication Date 2012-02-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.411 Times cited 12 Open Access
  Notes The authors thank E. Pellegrin for helpful comments and S. Macke for help with the software REMAGX. S.B. acknowledges financial support by the HZB, Berlin, and the Australian Government via Grant No. RM08550. H.T. acknowledges funding from GOA project “XANES meets ELNES,” J.V. and G.V.T. acknowledge funding from the European Research Council under Grant No. 46791-COUN-TATOMS. The authors acknowledge financial support by the DFG through Forschergruppe FOR 1162. Approved Most recent IF: 3.411; 2012 IF: 3.794
  Call Number UA @ lucian @ c:irua:95041UA @ admin @ c:irua:95041 Serial 1860
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Author Retuerto, M.; Li, M.R.; Go, Y.B.; Ignatov, A.; Croft, M.; Ramanujachary, K.V.; Hadermann, J.; Hodges, J.P.; Herber, R.H.; Nowik, I.; Greenblatt, M.;
  Title Magnetic and structural studies of the multifunctional material SrFe0.75Mo0.25O3-\text{\textgreek{d}} Type A1 Journal article
  Year (down) 2012 Publication Inorganic chemistry Abbreviated Journal Inorg Chem
  Volume 51 Issue 22 Pages 12273-12280
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract SrFe0.75Mo0.25O3-delta has been recently discovered as an extremely efficient electrode for intermediate temperature solid oxide fuel cells (IT-SOFCs). We have performed structural and magnetic studies to fully characterize this multifunctional material. We have observed by powder neutron diffraction (PND) and transmission electron microscopy (TEM) that its crystal symmetry is better explained with a tetragonal symmetry (I4/mcm space group) than with the previously reported orthorhombic symmetry (Pnma space group). The temperature dependent magnetic properties indicate an exceptionally high magnetic ordering temperature (T-N similar to 750 K), well above room temperature. The ordered magnetic structure at low temperature was determined by PND to be an antiferromagnetic coupling of the Fe cations. Mossbauer spectroscopy corroborated the PND results. A detailed study, with X-ray absorption spectroscopy (XAS), in agreement with the Mossbauer results, confirmed the formal oxidation states of the cations to be mixed valence Fe3+/4+ and Mo6+.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Easton, Pa Editor
  Language Wos 000311173700024 Publication Date 2012-10-26
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0020-1669;1520-510X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.857 Times cited 12 Open Access
  Notes Approved Most recent IF: 4.857; 2012 IF: 4.593
  Call Number UA @ lucian @ c:irua:105142 Serial 1862
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Author Müller, A.; Milošević, M.V.; Dale, S.E.C.; Engbarth, M.A.; Bending, S.J.
  Title Magnetization measurements and Ginzburg-Landau simulations of micron-size \beta-tin samples : evidence for an unusual critical behavior of mesoscopic type-I superconductors Type A1 Journal article
  Year (down) 2012 Publication Physical review letters Abbreviated Journal Phys Rev Lett
  Volume 109 Issue 19 Pages 197003
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We describe investigations of the largely unexplored field of mesoscopic type-I superconductors. Micromagnetometry and 3D Ginzburg-Landau simulations of our single crystal β-tin samples in this regime reveal size- and temperature-dependent supercritical fields whose behavior is radically different from the bulk critical field HcB. We find that complete suppression of the intermediate state in medium-size samples can result in a surprising reduction of the critical field significantly below HcB. We also reveal an evolution of the superconducting-to-normal phase transition from the expected irreversible first order at low temperatures through the previously unobserved reversible first-order to a second-order transition close to Tc, where the critical field can be many times larger than HcB. Finally, we have identified striking correlations between the mesoscopic Hc3 for nucleation of surface superconductivity and the thermodynamic Hc near Tc. All these observations are entirely unexpected in the conventional type-I picture.
  Address
  Corporate Author Thesis
  Publisher Place of Publication New York, N.Y. Editor
  Language Wos 000310853100017 Publication Date 2012-11-09
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 8.462 Times cited 21 Open Access
  Notes ; This work was supported by the EPSRC-UK under Grant No. EP/E039944/1, and the Flemish Science Foundation (FWO). ; Approved Most recent IF: 8.462; 2012 IF: 7.943
  Call Number UA @ lucian @ c:irua:102401 Serial 1893
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Author Berdiyorov, G.R.; Chao, X.H.; Peeters, F.M.; Wang, H.B.; Moshchalkov, V.V.; Zhu, B.Y.
  Title Magnetoresistance oscillations in superconducting strips : a Ginzburg-Landau study Type A1 Journal article
  Year (down) 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 86 Issue 22 Pages 224504-224508
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Within the time-dependent Ginzburg-Landau theory we study the dynamic properties of current-carrying superconducting strips in the presence of a perpendicular magnetic field. We found pronounced voltage peaks as a function of the magnetic field, the amplitude of which depends both on sample dimensions and external parameters. These voltage oscillations are a consequence of moving vortices, which undergo alternating static and dynamic phases. At higher fields or for high currents, the continuous motion of vortices is responsible for the monotonic background on which the resistance oscillations due to the entry of additional vortices are superimposed. Mechanisms for such vortex-assisted resistance oscillations are discussed. Qualitative changes in the magnetoresistance curves are observed in the presence of random defects, which affect the dynamics of vortices in the system.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000312064300004 Publication Date 2012-12-10
  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 31 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the ESF-NES program. G. R. B. acknowledges support from FWO-Vl. B.Y.Z. acknowledges the support from the MOST 973 Projects No. 2011CBA00110 and No. 2009CB930803, and the National Natural Science Foundation of China. V. V. M. acknowledges support from the Methusalem Funding by the Flemish Government. ; Approved Most recent IF: 3.836; 2012 IF: 3.767
  Call Number UA @ lucian @ c:irua:105969 Serial 1930
Permanent link to this record
 

 
Author Zarenia, M.; Vasilopoulos, P.; Peeters, F.M.
  Title Magnetotransport in periodically modulated bilayer graphene Type A1 Journal article
  Year (down) 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 85 Issue 24 Pages 245426-245426,10
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Magnetotransport in bilayer graphene in the presence of a weak and periodic potential is investigated in the presence of a perpendicular magnetic field B. The modulation broadens the Landau levels into bands and for weak magnetic fields leads to the well-known Weiss oscillations in their bandwidth and their transport coefficients at very low B and to the Shubnikov-de Haas oscillations at larger B. The amplitude of the Weiss oscillations is severely reduced if the periodic potentials applied to the two layers oscillate out of phase. We also contrast some results with those corresponding to single-layer graphene. Relative to them the flat-band condition and the oscillation amplitude differ substantially, due to the interlayer coupling, and agree only when this coupling is extremely weak. We further show that the Hall conductivity exhibits the well-known steps at half-integer and integer multiples of 4e(2)/h in single-layer and bilayer graphene, respectively, even for very weak magnetic fields. The results are pertinent to weak and periodic corrugations when the potential modulation dominates the strain-induced magnetic modulation.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000305253600012 Publication Date 2012-06-14
  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 21 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES program EuroGRAPHENE (project CON-GRAN), and the Canadian NSERC Grant No. OGP0121756. ; Approved Most recent IF: 3.836; 2012 IF: 3.767
  Call Number UA @ lucian @ c:irua:99077 Serial 1934
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Author Kalidindi, S.B.; Hyunchul, O.; Hirscher, M.; Esken, D.; Wiktor, C.; Turner, S.; Van Tendeloo, G.; Fischer, R.A.
  Title Metal@COFs : covalent organic frameworks as templates for Pd nanoparticles and hydrogen storage properties of Pd@COF-102 hybrid material Type A1 Journal article
  Year (down) 2012 Publication Chemistry: a European journal Abbreviated Journal Chem-Eur J
  Volume 18 Issue 35 Pages 10848-10856
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Three-dimensional covalent organic frameworks (COFs) have been demonstrated as a new class of templates for nanoparticles. Photodecomposition of the [Pd(eta 3-C3H5)(eta 5-C5H5)]@COF-102 inclusion compound (synthesized by a gas-phase infiltration method) led to the formation of the Pd@COF-102 hybrid material. Advanced electron microscopy techniques (including high-angle annular dark-field scanning transmission electron microscopy and electron tomography) along with other conventional characterization techniques unambiguously showed that highly monodisperse Pd nanoparticles ((2.4 +/- 0.5) nm) were evenly distributed inside the COF-102 framework. The Pd@COF-102 hybrid material is a rare example of a metal-nanoparticle-loaded porous crystalline material with a very narrow size distribution without any larger agglomerates even at high loadings (30 wt %). Two samples with moderate Pd content (3.5 and 9.5 wt %) were used to study the hydrogen storage properties of the metal-decorated COF surface. The uptakes at room temperature from these samples were higher than those of similar systems such as Pd@metalorganic frameworks (MOFs). The studies show that the H2 capacities were enhanced by a factor of 2-3 through Pd impregnation on COF-102 at room temperature and 20 bar. This remarkable enhancement is not just due to Pd hydride formation and can be mainly ascribed to hydrogenation of residual organic compounds, such as bicyclopentadiene. The significantly higher reversible hydrogen storage capacity that comes from decomposed products of the employed organometallic Pd precursor suggests that this discovery may be relevant to the discussion of the spillover phenomenon in metal/MOFs and related systems.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Weinheim Editor
  Language Wos 000307782800013 Publication Date 2012-08-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0947-6539; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 5.317 Times cited 88 Open Access
  Notes Fwo Approved Most recent IF: 5.317; 2012 IF: 5.831
  Call Number UA @ lucian @ c:irua:100469 Serial 2007
Permanent link to this record
 

 
Author Neyts, E.; Mao, M.; Eckert, M.; Bogaerts, A.
  Title Modeling aspects of plasma-enhanced chemical vapor deposition of carbon-based materials Type H1 Book chapter
  Year (down) 2012 Publication Abbreviated Journal
  Volume Issue Pages 245-290
  Keywords H1 Book chapter; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher CRC Press Place of Publication Boca Raton, Fla Editor
  Language Wos Publication Date 0000-00-00
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN ISBN 978-1-4398-6676-4 Additional Links UA library record
  Impact Factor Times cited Open Access
  Notes Approved Most recent IF: NA
  Call Number UA @ lucian @ c:irua:107843 Serial 2109
Permanent link to this record
 

 
Author Bogaerts, A.; Aerts, R.; Snoeckx, R.; Somers, W.; Van Gaens, W.; Yusupov, M.; Neyts, E.
  Title Modeling of plasma and plasma-surface interactions for medical, environmental and nano applications Type A1 Journal article
  Year (down) 2012 Publication Journal of physics : conference series Abbreviated Journal
  Volume 399 Issue Pages 012011
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract In this paper, an overview is given of modeling investigations carried out in our research group for a better understanding of plasmas used for medical, environmental and nano applications. The focus is both on modeling the plasma chemistry and the plasma-surface interactions. The plasma chemistry provides the densities and fluxes of the important plasma species. This information can be used as input when modeling the plasma-surface interactions. The combination of plasma simulations and plasma – surface interaction simulations provides a more comprehensive understanding of the underlying processes for these applications.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Bristol Editor
  Language Wos 000312261700011 Publication Date 2012-11-26
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1742-6588;1742-6596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor Times cited 7 Open Access
  Notes Approved Most recent IF: NA
  Call Number UA @ lucian @ c:irua:104727 Serial 2130
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Author Neek-Amal, M.; Covaci, L.; Peeters, F.M.
  Title Nanoengineered nonuniform strain in graphene using nanopillars Type A1 Journal article
  Year (down) 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 86 Issue 4 Pages 041405
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Recent experiments showed that nonuniform strain can be produced by depositing graphene over pillars. We employed atomistic calculations to study the nonuniform strain and the induced pseudomagnetic field in graphene on top of nanopillars. By decreasing the distance between the nanopillars a complex distribution for the pseudomagnetic field can be generated. Furthermore, we performed tight-binding calculations of the local density of states (LDOS) by using the relaxed graphene configuration obtained from atomistic calculations. We find that the quasiparticle LDOS are strongly modified near the pillars, both at low energies showing sublattice polarization and at high energies showing shifts of the van Hove singularity. Our study shows that changing the specific pattern of the nanopillars allows us to create a desired shape of the pseudomagnetic field profile while the LDOS maps provide an input for experimental verification by scanning tunneling microscopy.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lancaster, Pa Editor
  Language Wos 000306313900001 Publication Date 2012-07-14
  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 51 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-V1) and the EuroGRAPHENE project CONGRAN. ; Approved Most recent IF: 3.836; 2012 IF: 3.767
  Call Number UA @ lucian @ c:irua:100765 Serial 2255
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Author Schattschneider, P.; Stoeger-Pollach, M.; Verbeeck, J.
  Title Novel vortex generator and mode converter for electron beams Type A1 Journal article
  Year (down) 2012 Publication Physical review letters Abbreviated Journal Phys Rev Lett
  Volume 109 Issue 8 Pages 084801-1
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract A mode converter for electron vortex beams is described. Numerical simulations, confirmed by experiment, show that the converter transforms a vortex beam with a topological charge m = +/- 1 into beams closely resembling Hermite-Gaussian HG(10) and HG(01) modes. The converter can be used as a mode discriminator or filter for electron vortex beams. Combining the converter with a phase plate turns a plane wave into modes with topological charge m = +/- 1. This combination serves as a generator of electron vortex beams of high brilliance.
  Address
  Corporate Author Thesis
  Publisher Place of Publication New York, N.Y. Editor
  Language Wos 000307790900004 Publication Date 2012-08-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 8.462 Times cited 74 Open Access
  Notes Countatoms; Vortex ECASJO_; Approved Most recent IF: 8.462; 2012 IF: 7.943
  Call Number UA @ lucian @ c:irua:101103UA @ admin @ c:irua:101103 Serial 2384
Permanent link to this record
 

 
Author Aghaei, M.; Lindner, H.; Bogaerts, A.
  Title Optimization of operating parameters for inductively coupled plasma mass spectrometry : a computational study Type A1 Journal article
  Year (down) 2012 Publication Spectrochimica acta: part B : atomic spectroscopy Abbreviated Journal Spectrochim Acta B
  Volume 76 Issue Pages 56-64
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract An inductively coupled plasma, connected to a mass spectrometer interface, is computationally investigated. The effect of pressure behind the sampler, injector gas flow rate, auxiliary gas flow rate, and applied power is studied. There seems to be an optimum range of injector gas flow rate for each setup which guaranties the presence and also a proper length of the central channel in the torch. Moreover, our modeling results show that for any specific purpose, it is possible to control that either only the central gas flow passes through the sampler orifice or that it is accompanied by the auxiliary gas flow. It was also found that depending on geometry, the variation of outgoing gas flow rate is much less than the variation of the injector gas flow rate and this causes a slightly higher pressure inside the torch. The general effect of increasing the applied power is a rise in the plasma temperature, which results in a higher ionization in the coil region. However, the negative effect is reducing the length of the cool central channel which is important to transfer the sample substances to the sampler. Using a proper applied power can enhance the efficiency of the system. Indeed, by changing the gas path lines, the power can control which flow (i.e., only from injector gas or also from the auxiliary gas) goes to the sampler orifice. Finally, as also reported from experiments in literature, the pressure behind the sampler has no dramatic effect on the plasma characteristics.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Oxford Editor
  Language Wos 000311008600008 Publication Date 2012-06-23
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0584-8547; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.241 Times cited 18 Open Access
  Notes Approved Most recent IF: 3.241; 2012 IF: 3.141
  Call Number UA @ lucian @ c:irua:101356 Serial 2488
Permanent link to this record
 

 
Author Scarrozza, M.; Pourtois, G.; Houssa, M.; Heyns, M.; Stesmans, A.
  Title Oxidation of the GaAs(001) surface : insights from first-principles calculations Type A1 Journal article
  Year (down) 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 85 Issue 19 Pages 195307-195307,8
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract We performed a detailed investigation of the oxidation of the technologically relevant GaAs(001)-beta 2(2x4) surface via density functional calculations. The purpose is to gain insights on the atomistic mechanisms and local bondings that underlie the degradation of the surface properties once exposed to oxygen. The study comprises the adsorption of single O atoms, through the sampling of several adsorption sites, and the subsequent formation of the O adsorbate at increasing coverage by taking into account multiple-atom adsorption. Based on the evaluation of the energetics and the structural properties of the atomistic models generated, the results here reported delineate a consistent picture of the initial stage of the surface oxidation: (i) at low coverage, in the limit of single O insertions, oxygen is incorporated on the surface forming a twofold-bridging Ga-O-As bond; (ii) at increasing coverage, as multiple O atoms are involved, this is accompanied by the formation of a threefold-coordinated bond (with two Ga and one As atoms); (iii) the latter has important implications regarding the electronic properties of the adsorbate since this O bonding may result in the formation of As dangling bonds. Moreover, a clear trend of increased energy gain for the incorporation of neighboring O atoms compared to single O insertions indicates that the formation of oxide clusters is favored over a regime of uniform oxidation. Our findings provide a detailed description of the O bonding and stress the importance of modeling the adsorption of multiple O atoms for an accurate description of the surface oxidation.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000303755700006 Publication Date 2012-05-08
  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 15 Open Access
  Notes Approved Most recent IF: 3.836; 2012 IF: 3.767
  Call Number UA @ lucian @ c:irua:99122 Serial 2538
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Author Frolov, D.D.; Kotovshchikov, Y.N.; Morozov, I.V.; Boltalin, A.I.; Fedorova, A.A.; Marikutsa, A.V.; Rumyantseva, M.N.; Gaskov, A.M.; Sadovskaya, E.M.; Abakumov, A.M.
  Title Oxygen exchange on nanocrystalline tin dioxide modified by palladium Type A1 Journal article
  Year (down) 2012 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
  Volume 186 Issue Pages 1-8
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Temperature-programmed oxygen isotopic exchange study was performed on nanocrystalline tin dioxide-based materials synthesized via sol-gel route and modified by palladium. Such materials are widely used as resistive gas sensors. The experiments were carried out in a flow-reactor up to complete isotopic substitution of oxygen. Substantial rates of isotopic exchange for SnO2 were observed from about 700 K. The distribution of isotopic molecules O-16(2). (OO)-O-16-O-18 and O-18(2) corresponds to simple dioxygen heteroexchange mechanism with single lattice oxygen atom. The modification of SnO2 by Pd introduced multiple heteroexchange mechanism with preliminary O-2 dissociation on the clusters surface. Spill-over of atomic oxygen from Pd to the surface of SnO2 and fast exchange with lattice oxygen result in more than 100% increase of apparent heteroexchange rate. The exchange on SnO2/Pd was shown to be a complex process involving partial deactivation of the catalytic centers at temperature higher than 750 K. (C) 2011 Elsevier Inc. All rights reserved.
  Address
  Corporate Author Thesis
  Publisher Place of Publication London Editor
  Language Wos 000299801400001 Publication Date 2011-12-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0022-4596; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.299 Times cited 34 Open Access
  Notes Approved Most recent IF: 2.299; 2012 IF: 2.040
  Call Number UA @ lucian @ c:irua:96202 Serial 2546
Permanent link to this record
 

 
Author Tytgat, T.; Hauchecorne, B.; Abakumov, A.M.; Smits, M.; Verbruggen, S.W.; Lenaerts, S.
  Title Photocatalytic process optimisation for ethylene oxidation Type A1 Journal article
  Year (down) 2012 Publication Chemical engineering journal Abbreviated Journal Chem Eng J
  Volume 209 Issue Pages 494-500
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Sustainable Energy, Air and Water Technology (DuEL)
  Abstract When studying photocatalysis it is important to consider, beside the chemical approach, the engineering part related to process optimisation. To achieve this a fixed bed photocatalytic set-up consisting of different catalyst placings, in order to vary catalyst distribution, is studied. The use of a fixed quantity of catalyst placed packed or randomly distributed in the reactor, results in an almost double degradation for the distributed catalyst. Applying this knowledge leads to an improved performance with limited use of catalyst. A reactor only half filled with catalyst leads to higher degradation performance compared to a completely filled reactor. Taking into account this simple process optimisation by better distributing the catalyst a more sustainable photocatalytic air purification process is achieved. (C) 2012 Elsevier B.V. All rights reserved.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Lausanne Editor
  Language Wos 000311190500058 Publication Date 2012-08-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1385-8947; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.216 Times cited 12 Open Access
  Notes ; We are grateful for the delivered photocatalyst by Evonik as well as for the PhD grant (T. Tytgat) given by the Institute of Innovation by Science and Technology in Flanders (IWT). ; Approved Most recent IF: 6.216; 2012 IF: 3.473
  Call Number UA @ lucian @ c:irua:105185 Serial 2609
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Author Li, M.R.; Adem, U.; McMitchell, S.R.C.; Xu, Z.; Thomas, C.I.; Warren, J.E.; Giap, D.V.; Niu, H.; Wan, X.; Palgrave, R.G.; Schiffmann, F.; Cora, F.; Slater, B.; Burnett, T.L.; Cain, M.G.; Abakumov, A.M.; Van Tendeloo, G.; Thomas, M.F.; Rosseinsky, M.J.; Claridge, J.B.;
  Title A polar corundum oxide displaying weak ferromagnetism at room temperature Type A1 Journal article
  Year (down) 2012 Publication Journal of the American Chemical Society Abbreviated Journal J Am Chem Soc
  Volume 134 Issue 8 Pages 3737-3747
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Combining long-range magnetic order with polarity in the same structure is a prerequisite for the design of (magnetoelectric) multiferroic materials. There are now several demonstrated strategies to achieve this goal, but retaining magnetic order above room temperature remains a difficult target. Iron oxides in the +3 oxidation state have high magnetic ordering temperatures due to the size of the coupled moments. Here we prepare and characterize ScFeO3 (SFO), which under pressure and in strain-stabilized thin films adopts a polar variant of the corundum structure, one of the archetypal binary oxide structures. Polar corundum ScFeO3 has a weak ferromagnetic ground state below 356 K-this is in contrast to the purely antiferromagnetic ground state adopted by the well-studied ferroelectric BiFeO3.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Washington, D.C. Editor
  Language Wos 000301161600027 Publication Date 2012-01-23
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0002-7863;1520-5126; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 13.858 Times cited 48 Open Access
  Notes Approved Most recent IF: 13.858; 2012 IF: 10.677
  Call Number UA @ lucian @ c:irua:97200 Serial 2658
Permanent link to this record
 

 
Author Clem, J.R.; Mawatari, Y.; Berdiyorov, G.R.; Peeters, F.M.
  Title Predicted field-dependent increase of critical currents in asymmetric superconducting nanocircuits Type A1 Journal article
  Year (down) 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
  Volume 85 Issue 14 Pages 144511-144511,16
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The critical current of a thin superconducting strip of width W much larger than the Ginzburg-Landau coherence length xi but much smaller than the Pearl length Lambda = 2 lambda(2)/d is maximized when the strip is straight with defect-free edges. When a perpendicular magnetic field is applied to a long straight strip, the critical current initially decreases linearly with H but then decreases more slowly with H when vortices or antivortices are forced into the strip. However, in a superconducting strip containing sharp 90 degrees or 180 degrees turns, the zero-field critical current at H = 0 is reduced because vortices or antivortices are preferentially nucleated at the inner corners of the turns, where current crowding occurs. Using both analytic London-model calculations and time-dependent Ginzburg-Landau simulations, we predict that in such asymmetric strips the resulting critical current can be increased by applying a perpendicular magnetic field that induces a current-density contribution opposing the applied current density at the inner corners. This effect should apply to all turns that bend in the same direction.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000302611100004 Publication Date 2012-04-10
  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 40 Open Access
  Notes ; This research, supported in part by the US Department of Energy, Office of Basic Energy Science, Division of Materials Sciences and Engineering, was performed in part at the Ames Laboratory, which is operated for the US Department of Energy by Iowa State University under Contract No. DE-AC02-07CH11358. This work also was supported in part by the Flemish Science Foundation (FWO-Vlaanderen) and the Belgian Science Policy (IAP). G.R.B. acknowledges individual support from FWO-Vlaanderen. ; Approved Most recent IF: 3.836; 2012 IF: 3.767
  Call Number UA @ lucian @ c:irua:98263 Serial 2695
Permanent link to this record
 

 
Author Sliem, M.A.; Turner, S.; Heeskens, D.; Kalidindi, S.B.; Van Tendeloo, G.; Muhler, M.; Fischer, R.A.
  Title Preparation, microstructure characterization and catalytic performance of Cu/ZnO and ZnO/Cu composite nanoparticles for liquid phase methanol synthesis Type A1 Journal article
  Year (down) 2012 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
  Volume 14 Issue 22 Pages 8170-8178
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Stearate@Cu/ZnO nanocomposite particles with molar ratios of ZnO ∶ Cu = 2 and 5 are synthesized by reduction of the metalorganic Cu precursor [Cu{(OCH(CH3)CH2N(CH3)2)}2] in the presence of stearate@ZnO nanoparticles. In the case of ZnO ∶ Cu = 5, high-angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) combined with electron-energy-loss-spectroscopy (EELS) as well as attenuated total reflection Fourier transform infrared (ATR-IR) spectroscopy are used to localize the small amount of Cu deposited on the surface of 35 nm sized stearate@ZnO particles. For ZnO ∶ Cu = 2, the microstructure of the nanocomposites after catalytic activity testing is characterized by HAADF-STEM techniques. This reveals the construction of large Cu nanoparticles (2050 nm) decorated by small ZnO nanoparticles (35 nm). The catalytic activity of both composites for the synthesis of methanol from syn gas is evaluated.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Cambridge Editor
  Language Wos 000304102200033 Publication Date 2012-04-16
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1463-9076;1463-9084; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.123 Times cited 16 Open Access
  Notes Fwo Approved Most recent IF: 4.123; 2012 IF: 3.829
  Call Number UA @ lucian @ c:irua:98377 Serial 2702
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Author Kuznetsov, A.S.; Lu, Y.-G.; Turner, S.; Shestakov, M.V.; Tikhomirov, V.K.; Kirilenko, D.; Verbeeck, J.; Baranov, A.N.; Moshchalkov, V.V.
  Title Preparation, structural and optical characterization of nanocrystalline ZnO doped with luminescent Ag-nanoclusters Type A1 Journal article
  Year (down) 2012 Publication Optical materials express Abbreviated Journal Opt Mater Express
  Volume 2 Issue 6 Pages 723-734
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Nanocrystalline ZnO doped with Ag-nanoclusters has been synthesized by a salt solid state reaction. Three overlapping broad emission bands due to the Ag nanoclusters have been detected at about 570, 750 and 900 nm. These emission bands are excited by an energy transfer from the exciton state of the ZnO host when pumped in the wavelength range from 250 to 400 nm. The 900 nm emission band shows characteristic orbital splitting into three components pointing out that the anisotropic crystalline wurtzite host of ZnO is responsible for this feature. Heat-treatment and temperature dependence studies confirm the origin of these emission bands. An energy level diagram for the emission process and a model for Ag nanoclusters sites are suggested. The emission of nanocrystalline ZnO doped with Ag nanoclusters may be applied for white light generation, displays driven by UV light, down-convertors for solar cells and luminescent lamps.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000304953700004 Publication Date 2012-04-30
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2159-3930; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.591 Times cited Open Access
  Notes We are grateful to the Methusalem Funding of Flemish Government for the support of this work. Y.-G. L. and S. T. acknowledge funding from the Fund for Scientific Research Flanders (FWO) for a postdoctoral grant and under grant number G056810N. The microscope used in this study was partially financed by the Hercules Foundation. J.V. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC grant No246791 – COUNTATOMS and ERC Starting Grant 278510 VORTEX. The authors acknowledge the guidance of Prof. G. Van Tendeloo, EMAT Antwerpen University, in transmission electron microscopy study in this work. ECASJO_; Approved Most recent IF: 2.591; 2012 IF: 2.616
  Call Number UA @ lucian @ c:irua:97709UA @ admin @ c:irua:97709 Serial 2707
Permanent link to this record
 

 
Author Boschker, H.; Verbeeck, J.; Egoavil, R.; Bals, S.; Van Tendeloo, G.; Huijben, M.; Houwman, E.P.; Koster, G.; Blank, D.H.A.; Rijnders, G.
  Title Preventing the reconstruction of the polar discontinuity at oxide heterointerfaces Type A1 Journal article
  Year (down) 2012 Publication Advanced functional materials Abbreviated Journal Adv Funct Mater
  Volume 22 Issue 11 Pages 2235-2240
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Perovskite oxide heteroepitaxy receives much attention because of the possibility to combine the diverse functionalities of perovskite oxide building blocks. A general boundary condition for the epitaxy is the presence of polar discontinuities at heterointerfaces. These polar discontinuities result in reconstructions, often creating new functionalities at the interface. However, for a significant number of materials these reconstructions are unwanted as they alter the intrinsic materials properties at the interface. Therefore, a strategy to eliminate this reconstruction of the polar discontinuity at the interfaces is required. We show that the use of compositional interface engineering can prevent the reconstruction at the La0.67Sr0.33MnO3/SrTiO3 (LSMO/STO) interface. The polar discontinuity at this interface can be removed by the insertion of a single La0.33Sr0.67O layer, resulting in improved interface magnetization and electrical conductivity.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Weinheim Editor
  Language Wos 000304749600002 Publication Date 2012-03-23
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1616-301X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 12.124 Times cited 72 Open Access
  Notes We wish to acknowledge the financial support of the Dutch Science Foundation (NWO) and the Dutch Nanotechnology program NanoNed. S. B. acknowledges the financial support from the European Union under the Framework 6 program under a contract for an Integrated Infrastructure Initiative. Reference 026019 ESTEEM. J. V. and G. V. T. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC grant N246791 – COUNTATOMS. R. E. acknowledges funding by the European Union Council under the 7th Framework Program (FP7) grant NNMP3-LA-2010-246102 IFOX. We thank Sandra Van Aert for stimulating discussions. Approved Most recent IF: 12.124; 2012 IF: 9.765
  Call Number UA @ lucian @ c:irua:98907UA @ admin @ c:irua:98907 Serial 2712
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Author Quintana, M.; Grzelczak, M.; Spyrou, K.; Kooi, B.; Bals, S.; Van Tendeloo, G.; Rudolf, P.; Prato, M.
  Title Production of large graphene sheets by exfoliation of graphite under high power ultrasound in the presence of tiopronin Type A1 Journal article
  Year (down) 2012 Publication Chemical communications Abbreviated Journal Chem Commun
  Volume 48 Issue 100 Pages 12159-12161
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Under ultrasonication, the production of high quality graphene layers by exfoliation of graphite was achieved via addition of tiopronin as an antioxidant.
  Address
  Corporate Author Thesis
  Publisher Place of Publication London Editor
  Language Wos 000311411100003 Publication Date 2012-10-09
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1359-7345;1364-548X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.319 Times cited 39 Open Access
  Notes This work was financially supported by the University of Trieste, INSTM, Italian Ministry of Education MIUR (cofin Prot. 20085M27SS) and by the "Graphene-based electronics'' research program of the Foundation for Fundamental Research on Matter (FOM). Part of this work was supported by funding from the ERC grant No 246791COUNTATOMS. MQ acknowledges the financial support from CONACyT CB-2011-01-166914 and FAI-UASLP. Approved Most recent IF: 6.319; 2012 IF: 6.378
  Call Number UA @ lucian @ c:irua:105230 Serial 2724
Permanent link to this record
 

 
Author Hardy, A.; Van Elshocht, S.; De Dobbelaere, C.; Hadermann, J.; Pourtois, G.; De Gendt, S.; Afanas'ev, V.V.; Van Bael, M.K.
  Title Properties and thermal stability of solution processed ultrathin, high-k bismuth titanate (Bi2Ti2O7) films Type A1 Journal article
  Year (down) 2012 Publication Materials research bulletin Abbreviated Journal Mater Res Bull
  Volume 47 Issue 3 Pages 511-517
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract Ultrathin bismuth titanate films (Bi2Ti2O7, 5-25 nm) are deposited onto SiO2/Si substrates by aqueous chemical solution deposition and their evolution during annealing is studied. The films crystallize into a preferentially oriented, pure pyrochlore phase between 500 and 700 degrees C, depending on the film thickness and the total thermal budget. Crystallization causes a strong increase of surface roughness compared to amorphous films. An increase of the interfacial layer thickness is observed after anneal at 600 degrees C, together with intermixing of bismuth with the substrate as shown by TEM-EDX. The band gap was determined to be similar to 3 eV from photoconductivity measurements and high dielectric constants between 30 and 130 were determined from capacitance voltage measurements, depending on the processing conditions. (C) 2012 Elsevier Ltd. All rights reserved.
  Address
  Corporate Author Thesis
  Publisher Place of Publication New York, N.Y. Editor
  Language Wos 000301994100001 Publication Date 2012-01-10
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0025-5408; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.446 Times cited Open Access
  Notes Approved Most recent IF: 2.446; 2012 IF: 1.913
  Call Number UA @ lucian @ c:irua:97797 Serial 2727
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