toggle visibility
Search within Results:
Display Options:

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Govaerts, K.; Sluiter, M.H.F.; Partoens, B.; Lamoen, D. url  doi
openurl 
  Title Stability of Sb-Te layered structures : first-principles study Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 85 Issue 14 Pages 144114-144114,8  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract Using an effective one-dimensional cluster expansion in combination with first-principles electronic structure calculations we have studied the energetics and electronic properties of Sb-Te layered systems. For a Te concentration between 0 and 60 at. % an almost continuous series of metastable structures is obtained consisting of consecutive Sb bilayers next to consecutive Sb2Te3 units, with the general formula (Sb-2)(n)(Sb2Te3)(m) (n, m = 1,2, ... ). Between 60 and 100 at.% no stable structures are found. We account explicitly for the weak van derWaals bonding between Sb bilayers and Sb2Te3 units by using a recently developed functional, which strongly improves the interlayer bonding distances. At T = 0 K, no evidence is found for the existence of two separate single-phase regions delta and gamma and a two-phase region delta + gamma. Metastable compounds with a Te concentration between 0 and 40 at. % are semimetallic, whereas compounds with a Te concentration between 50 and 60 at. % are semiconducting. Compounds with an odd number of Sb layers are metallic and have a much higher formation energy than those with an even number of consecutive Sb layers, thereby favoring the formation of Sb bilayers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000303115400004 Publication Date 2012-04-23  
  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 14 Open Access  
  Notes Iwt; Fwo Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98255 Serial 3129  
Permanent link to this record
 

 
Author Jalabert, D.; Pelloux-Gervais, D.; Béché, A.; Hartmann, J.M.; Gergaud, P.; Rouvière, J.L.; Canut, B. doi  openurl
  Title Depth strain profile with sub-nm resolution in a thin silicon film using medium energy ion scattering Type A1 Journal article
  Year 2012 Publication Physica Status Solidi A-Applications And Materials Science Abbreviated Journal Phys Status Solidi A  
  Volume 209 Issue 2 Pages 265-267  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The depth strain profile in silicon from the Si (001) substrate to the surface of a 2 nm thick Si/12 nm thick SiGe/bulk Si heterostructure has been determined by medium energy ion scattering (MEIS). It shows with sub-nanometer resolution and high strain sensitivity that the thin Si cap presents residual compressive strain caused by Ge diffusion coming from the fully strained SiGe layer underneath. The strain state of the SiGe buffer have been checked by X-ray diffraction (XRD) and nano-beam electron diffraction (NBED) measurements.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000303382700005 Publication Date 2011-11-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1862-6300; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.775 Times cited 3 Open Access  
  Notes Approved Most recent IF: 1.775; 2012 IF: 1.469  
  Call Number UA @ lucian @ c:irua:136430 Serial 4497  
Permanent link to this record
 

 
Author Ribbens, S.; Beyers, E.; Schellens, K.; Mertens, M.; Ke, X.; Bals, S.; Van Tendeloo, G.; Meynen, V.; Cool, P. pdf  doi
openurl 
  Title Systematic evaluation of thermal and mechanical stability of different commercial and synthetic photocatalysts in relation to their photocatalytic activity Type A1 Journal article
  Year 2012 Publication Microporous and mesoporous materials: zeolites, clays, carbons and related materials Abbreviated Journal Micropor Mesopor Mat  
  Volume 156 Issue Pages 62-72  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)  
  Abstract The effect of thermal treatment and mechanical stress on the structural and photocatalytic properties of eight different (synthetic and commercial) photocatalysts has been thoroughly investigated. Different mesoporous Ti-based materials were prepared via surfactant based synthesis routes (e.g. Pluronic 123, CTMABr = Cetyltrimethylammonium bromide) or via template-free synthesis routes (e.g. trititanate nanotubes). Also, the stabilizing effect of the NaOH/NH4OH post-treatment on the templated mesoporous materials and their photocatalytic activity was investigated. Furthermore, the thermal and mechanical properties of commercially available titanium dioxides such as P25 Evonik® and Millenium PC500® were studied. The various photocatalysts were analyzed with N2-sorption, X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) to obtain information concerning the specific surface area, pore volume, crystal structure, morphology, phase transitions, etc. In general, results show that the NaOH post-treatment leads to an increased control of the crystallization process during calcination resulting in a higher thermal stability, but at the same time diminishes the photocatalytic activity. Mesoporous materials in which pre-synthesized nanoparticles are used as titania source have the best mechanical stability whereas the mechanical stability of the nanotubes is the most limited. At increased temperatures and pressures, the tested commercial titanium dioxides lose their superior photocatalytic activity caused by a decreased accessibility of the active sites. The observed changes in adsorption capacities and photocatalytic activities cannot be assigned to one single phenomenon. In this respect, it shows the need to define a general/standard method to compare different photocatalysts. Furthermore, it is shown that the photocatalytic properties do not necessarily deteriorate under thermal stress, but can be improved due to crystallization, even though the initial material is (partially) destroyed. It is shown that the usefulness of a specific type of photocatalyst strongly depends on the application and the temperature/pressure to which it needs to resist.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos (up) 000303625200010 Publication Date 2012-02-08  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1387-1811; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.615 Times cited 8 Open Access  
  Notes Fwo Approved Most recent IF: 3.615; 2012 IF: 3.365  
  Call Number UA @ lucian @ c:irua:96910 Serial 3466  
Permanent link to this record
 

 
Author Misko, V.R.; Nori, F. url  doi
openurl 
  Title Magnetic flux pinning in superconductors with hyperbolic-tesselation arrays of pinning sites Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 85 Issue 18 Pages 184506-184506,6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We study magnetic flux interacting with arrays of pinning sites (APSs) placed on vertices of hyperbolic tesselations (HTs). We show that, due to the gradient in the density of pinning sites, HT APSs are capable of trapping vortices for a broad range of applied magnetic fluxes. Thus, the penetration of magnetic field in HT APSs is essentially different from the usual scenario predicted by the Bean model. We demonstrate that, due to the enhanced asymmetry of the surface barrier for vortex entry and exit, this HT APS could be used as a “capacitor” to store magnetic flux.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000303653600005 Publication Date 2012-05-04  
  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 24 Open Access  
  Notes ; V.R.M. acknowledges support from the “Odysseus” Program of the Flemish Government & FWO-Vl, and the IAP. F.N. is partially supported by the ARO, NSF Grant No. 0726909, JSPS-RFBR Contract No. 12-02-92100, Grant-in-Aid for Scientific Research (S), MEXT Kakenhi on Quantum Cybernetics, and the JSPS via its FIRST program. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98224 Serial 1880  
Permanent link to this record
 

 
Author Scarrozza, M.; Pourtois, G.; Houssa, M.; Heyns, M.; Stesmans, A. url  doi
openurl 
  Title Oxidation of the GaAs(001) surface : insights from first-principles calculations Type A1 Journal article
  Year 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 (up) 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  
Permanent link to this record
 

 
Author Li, Z.; Covaci, L.; Marsiglio, F. url  doi
openurl 
  Title Impact of Dresselhaus versus Rashba spin-orbit coupling on the Holstein polaron Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 85 Issue 20 Pages 205112-205112,5  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We utilize an exact variational numerical procedure to calculate the ground-state properties of a polaron in the presence of Rashba and linear Dresselhaus spin-orbit coupling. We find that when the linear Dresselhaus spin-orbit coupling approaches the Rashba spin-orbit coupling, the Van Hove singularity in the density of states will be shifted away from the bottom of the band and finally disappear when the two spin-orbit couplings are tuned to be equal. The effective mass will be suppressed; the trend will become more significant for low phonon frequency. The presence of two dominant spin-orbit couplings will make it possible to tune the effective mass with more varied observables.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000303794900003 Publication Date 2012-05-09  
  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 in part by the Natural Sciences and Engineering Research Council of Canada (NSERC), by ICORE (Alberta), by the Flemish Science Foundation (FWO-Vl), and by the Canadian Institute for Advanced Research (CIfAR). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:99121 Serial 1558  
Permanent link to this record
 

 
Author Avetisyan, A.A.; Partoens, B.; Peeters, F.M. doi  openurl
  Title Electric field tuning of the band gap in four layers of graphene with different stacking order Type P1 Proceeding
  Year 2012 Publication Proceedings of the Society of Photo-optical Instrumentation Engineers T2 – Conference on Photonics and Micro and Nano-structured Materials, JUN 28-30, 2011, Yerevan, ARMENIA Abbreviated Journal  
  Volume Issue Pages 84140-84148  
  Keywords P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract We investigated the effect of different stacking order of the four graphene layer system on the induced band gap when positively charged top and negatively charged back gates are applied to the system. A tight-binding approach within a self-consistent Hartree approximation is used to calculate the induced charges on the different graphene layers. We show that the electric field does not open an energy gap if the multilayer graphene system contains a trilayer part with the ABA Bernal stacking.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000303856600012 Publication Date 2012-01-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume 8414 Series Issue Edition  
  ISSN ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), and the BelgianScience Policy (IAP). One of us (A.A.A.) was supported by a fellowship from the Belgian Federal Science Policy Office (BELSPO). ; Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:113046 Serial 886  
Permanent link to this record
 

 
Author Djotyan, A.P.; Avetisyan, A.A.; Hao, Y.L.; Peeters, F.M. doi  openurl
  Title Shallow donor near a semiconductor surface in the presence of locally spherical scanning tunneling microscope tip Type P1 Proceeding
  Year 2012 Publication Proceedings of the Society of Photo-optical Instrumentation Engineers T2 – Conference on Photonics and Micro and Nano-structured Materials, JUN 28-30, 2011, Yerevan, ARMENIA Abbreviated Journal  
  Volume Issue Pages 84140-84148  
  Keywords P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract We developed a variational approach to investigate the ground state energy and the extend of the wavefunction of a neutral donor located near a semiconductor surface in the presence of scanning tunneling microscope (STM) metallic tip. We apply the effective mass approximation and use a variational wavefunction that takes into account the influence of all image charges that arise due to the presence of a metallic tip. The behavior of the ground state energy when the tip approaches the semiconductor surface is investigated.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000303856600020 Publication Date 2012-01-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume 8414 Series Issue Edition  
  ISSN ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), and the Belgian Science Policy. One of us (AAA) was supported by a fellowship from the Belgian Federal Science Policy Office (Belspo). ; Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:113047 Serial 2987  
Permanent link to this record
 

 
Author Turner, S.; Verbeeck, J.; Ramezanipour, F.; Greedan, J.E.; Van Tendeloo, G.; Botton, G.A. pdf  doi
openurl 
  Title Atomic resolution coordination mapping in Ca2FeCoO5 brownmillerite by spatially resolved electron energy-loss spectroscopy Type A1 Journal article
  Year 2012 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 24 Issue 10 Pages 1904-1909  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Using a combination of high-angle annular dark field scanning transmission electron microscopy and atomically resolved electron energy-loss spectroscopy at high energy resolution in an aberration-corrected electron microscope, we demonstrate the capability of coordination mapping in complex oxides. Brownmillerite compound Ca2FeCoO5, consisting of repetitive octahedral and tetrahedral coordination layers with Fe and Co in a fixed 3+ valency, is selected to demonstrate the principle of atomic resolution coordination mapping. Analysis of the Co-L2,3 and the Fe-L2,3 edges shows small variations in the fine structure that can be specifically attributed to Co/Fe in tetrahedral or in octahedral coordination. Using internal reference spectra, we show that the coordination of the Fe and Co atoms in the compound can be mapped at atomic resolution.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos (up) 000304237500024 Publication Date 2012-04-25  
  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 33 Open Access  
  Notes A.M. Abakumov is thanked for fruitful discussions. S.T. gratefully acknowledges the Fund for Scientific Research Flanders (FWO). J.E.G. and GAB. acknowledge the support of the NSERC of Canada through Discovery Grants. The Canadian Centre for Electron Microscopy is a National Facility supported by NSERC and McMaster University and was funded by the Canada Foundation for Innovation and the Ontario Government. Part of this work was supported by funding from the European Research Council under the FP7, ERC Grant N 246791 COUNTATOMS and ERC Starting Grant N 278510 VORTEX. The EMAT microscope is partially funded by the Hercules fund of the Flemish Government. ECASJO_; Approved Most recent IF: 9.466; 2012 IF: 8.238  
  Call Number UA @ lucian @ c:irua:98379UA @ admin @ c:irua:98379 Serial 175  
Permanent link to this record
 

 
Author Simon, Q.; Barreca, D.; Gasparotto, A.; Maccato, C.; Montini, T.; Gombac, V.; Fornasiero, P.; Lebedev, O.I.; Turner, S.; Van Tendeloo, G. pdf  doi
openurl 
  Title Vertically oriented CuO/ZnO nanorod arrays : from plasma-assisted synthesis to photocatalytic H2 production Type A1 Journal article
  Year 2012 Publication Journal of materials chemistry Abbreviated Journal J Mater Chem  
  Volume 22 Issue 23 Pages 11739-11747  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract 1D CuO/ZnO nanocomposites were grown on Si(100) substrates by means of an original two-step synthetic strategy. ZnO nanorod (NR) arrays were initially deposited by plasma enhanced-chemical vapor deposition (PE-CVD) from an ArO2 atmosphere. Subsequently, tailored amounts of CuO were dispersed over zinc oxide matrices by radio frequency (RF)-sputtering of Cu from Ar plasmas, followed by thermal treatment in air. A thorough characterization of the obtained systems was carried out by X-ray photoelectron and X-ray excited-Auger electron spectroscopies (XPS and XE-AES), glancing incidence X-ray diffraction (GIXRD), field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDXS), atomic force microscopy (AFM), transmission electron microscopy (TEM), electron diffraction (ED) and energy filtered-TEM (EF-TEM). Pure and highly oriented CuO/ZnO NR arrays, free from ternary ZnCuO phases and characterized by a copper(II) oxide content controllable as a function of the adopted RF-power, were successfully obtained. Interestingly, the structural relationships between the two oxides at the CuO/ZnO interface were found to depend on the overall CuO loading. The obtained nanocomposites displayed promising photocatalytic performances in H2 production by reforming of ethanolwater solutions under simulated solar illumination, paving the way to the sustainable conversion of solar light into chemical energy.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge Editor  
  Language Wos (up) 000304351400046 Publication Date 2012-04-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0959-9428;1364-5501; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 74 Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:98382 Serial 3840  
Permanent link to this record
 

 
Author Badalyan, S.M.; Peeters, F.M. url  doi
openurl 
  Title Effect of nonhomogenous dielectric background on the plasmon modes in graphene double-layer structures at finite temperatures Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 85 Issue 19 Pages 195444-195444,6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We have calculated the plasmon modes in graphene double layer structures at finite temperatures, taking into account the inhomogeneity of the dielectric background of the system. The effective dielectric function is obtained from the solution of the Poisson equation of a three-layer dielectric medium with graphene sheets located at the interfaces, separating the different materials. Due to the momentum dispersion of the effective dielectric function, the intra- and interlayer bare Coulomb interactions in the graphene double layer system acquires an additional momentum dependence-an effect that is of the order of the interlayer interaction itself. We show that the energies of the in-phase and out-of-phase plasmon modes are determined largely by different values of the spatially dependent effective dielectric function. The effect of the dielectric inhomogeneity increases with temperature, and even at high temperatures the energy shift induced by the dielectric inhomogeneity and temperature itself remains larger than the broadening of the plasmon energy dispersions due to the Landau damping. The obtained new features of the plasmon dispersions can be observed in frictional drag measurements and in inelastic light scattering and electron energy-loss spectroscopies.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000304394800011 Publication Date 2012-05-23  
  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 67 Open Access  
  Notes ; We thank G. Vignale for useful discussions and acknowledge support from the Flemisch Science Foundation (FWO-Fl) and the Belgian Science Policy (BELSPO). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98941 Serial 826  
Permanent link to this record
 

 
Author Neek-Amal, M.; Peeters, F.M. url  doi
openurl 
  Title Strain-engineered graphene through a nanostructured substrate : 1 : deformations Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 85 Issue 19 Pages 195445-195445,11  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using atomistic simulations we investigate the morphological properties of graphene deposited on top of a nanostructured substrate. Sinusoidally corrugated surfaces, steps, elongated trenches, one-dimensional and cubic barriers, spherical bubbles, Gaussian bumps, and Gaussian depressions are considered as support structures for graphene. The graphene-substrate interaction is governed by van der Waals forces and the profile of the graphene layer is determined by minimizing the energy using molecular dynamics simulations. Based on the obtained optimum configurations, we found that (i) for graphene placed over sinusoidally corrugated substrates with corrugation wavelengths longer than 2 nm, the graphene sheet follows the substrate pattern while for supported graphene it is always suspended across the peaks of the substrate, (ii) the conformation of graphene to the substrate topography is enhanced when increasing the energy parameter in the van der Waals model, (iii) the adhesion of graphene into the trenches depends on the width of the trench and on the graphene's orientation, i. e., in contrast to a small-width (3 nm) nanoribbon with armchair edges, the one with zigzag edges follows the substrate profile, (iv) atomic-scale graphene follows a Gaussian bump substrate but not the substrate with a Gaussian depression, and (v) the adhesion energy due to van der Waals interaction varies in the range [0.1-0.4] J/m(2).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000304394800012 Publication Date 2012-05-23  
  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 62 Open Access  
  Notes ; We thank L. Covaci and S. Costamagna for valuable comments. We acknowledge M. Zarenia, M. R. Masir and D. Nasr for fruitful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl) and ESF EUROCORE program EuroGRAPHENE: CONGRAN. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98942 Serial 3166  
Permanent link to this record
 

 
Author Neek-Amal, M.; Peeters, F.M. url  doi
openurl 
  Title Strain-engineered graphene through a nanostructured substrate : 2 : pseudomagnetic fields Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 85 Issue 19 Pages 195446-195446,6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The strain-induced pseudomagnetic field in supported graphene deposited on top of a nanostructured substrate is investigated by using atomistic simulations. A step, an elongated trench, a one-dimensional barrier, a spherical bubble, a Gaussian bump, and a Gaussian depression are considered as support structures for graphene. From the obtained optimum configurations we found very strong induced pseudomagnetic fields which can reach up to similar to 1000 T due to the strain-induced deformations in the supported graphene. Different magnetic confinements with controllable geometries are found by tuning the pattern of the substrate. The resulting induced magnetic fields for graphene on top of a step, barrier, and trench are calculated. In contrast to the step and trench the middle part of graphene on top of a barrier has zero pseudomagnetic field. This study provides a theoretical background for designing magnetic structures in graphene by nanostructuring substrates. We found that altering the radial symmetry of the deformation changes the sixfold symmetry of the induced pseudomagnetic field.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000304394800013 Publication Date 2012-05-23  
  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 EUROCORE program EuroGRAPHENE: CONGRAN. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98943 Serial 3167  
Permanent link to this record
 

 
Author Badalyan, S.M.; Peeters, F.M. url  doi
openurl 
  Title Electron-phonon bound state in graphene Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 85 Issue 20 Pages 205453-205453,5  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The fine structure of the Dirac energy spectrum in graphene induced by electron-optical phonon coupling is investigated in the portion of the spectrum near the phonon emission threshold. The derived new dispersion equation in the immediate neighborhood below the threshold corresponds to an electron-phonon bound state. We find that the singular vertex corrections beyond perturbation theory strongly increase the electron-phonon binding energy scale. The predicted enhancement of the effective electron-phonon coupling can be measured using angle-resolved spectroscopy.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000304649400002 Publication Date 2012-05-30  
  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 thank E. Rashba for the useful discussion and acknowledge support from the Belgian Science Policy (IAP) and BELSPO. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98939 Serial 982  
Permanent link to this record
 

 
Author Krstajić, P.M.; Peeters, F.M. url  doi
openurl 
  Title Energy-momentum dispersion relation of plasmarons in graphene Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 85 Issue 20 Pages 205454-205454,4  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The many-body correction to the band structure of a quasi-free-standing graphene layer is obtained within the Overhauser approach, where the electron-plasmon interaction is described as a field theoretical problem. We find that the Dirac-like spectrum is shifted by Delta E(k = 0), which is on the order of 50-150 meV, depending on the electron concentration n(e), and is in semiquantitative agreement with experimental data. The value of the Fermi velocity is renormalized by several percents and decreases with increasing electron concentration as found experimentally.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000304649900004 Publication Date 2012-06-05  
  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 ; This work was supported by the Flemish Science Foundation (FWO-Vl), the ESF-EuroGRAPHENE project CON-GRAN, and the Serbian Ministry of Education and Science (project No. TR 32008). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98937 Serial 1043  
Permanent link to this record
 

 
Author Savchenko, D.V.; Serdan, A.A.; Morozov, V.A.; Van Tendeloo, G.; Ionov, S.G. pdf  doi
openurl 
  Title Improvement of the oxidation stability and the mechanical properties of flexible graphite foil by boron oxide impregnation Type A1 Journal article
  Year 2012 Publication New carbon materials Abbreviated Journal  
  Volume 27 Issue 1 Pages 12-18  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Flexible graphite foil produced by rolling expanded graphite impregnated with boron oxide was analyzed by laser mass spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and thermogravimetry. It was shown that the modification of the graphite foil by boron oxide increases the onset temperature of oxidation by ∼ 150 °C. Impregnation of less than 2 mass% boron oxide also increased the tensile strength of the materials. The observed improvement was attributed to the blocking of active sites by boron oxide, which is probably chemically bonded to the edges of graphene sheets in expanded graphite particles.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000304742100002 Publication Date 2012-03-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1872-5805; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 5 Open Access  
  Notes Iap Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:96958 Serial 1569  
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. pdf  doi
openurl 
  Title Preventing the reconstruction of the polar discontinuity at oxide heterointerfaces Type A1 Journal article
  Year 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 (up) 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  
Permanent link to this record
 

 
Author Pogosov, W.V.; Misko, V.R. url  doi
openurl 
  Title Vortex quantum tunneling versus thermal activation in ultrathin superconducting nanoislands Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 85 Issue 22 Pages 224508-224508,5  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We consider two possible mechanisms for single-vortex fluctuative entry/exit through the surface barrier in ultrathin superconducting disk-shaped nanoislands made of Pb and consisting of just a few monoatomic layers, which can be fabricated using modern techniques. We estimate tunneling probabilities and establish criteria for the crossover between these two mechanisms depending on magnetic field and system sizes. For the case of vortex entry, quantum tunneling dominates on the major part of the temperature/flux phase diagram. For the case of vortex exit, thermal activation turns out to be more probable. This nontrivial result is due to the subtle balance between the barrier height and width, which determine rates of the thermal activation and quantum tunneling, respectively.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000304856600003 Publication Date 2012-06-07  
  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 2 Open Access  
  Notes ; This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl). W. V. P. acknowledges numerous discussions with A. O. Sboychakov and the support from the Dynasty Foundation, the RFBR (Project No. 12-02-00339), and RFBR-CNRS programme (Project No. 12-02-91055). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98908 Serial 3882  
Permanent link to this record
 

 
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. url  doi
openurl 
  Title Preparation, structural and optical characterization of nanocrystalline ZnO doped with luminescent Ag-nanoclusters Type A1 Journal article
  Year 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 (up) 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 Dendooven, J.; Goris, B.; Devloo-Casier, K.; Levrau, E.; Biermans, E.; Baklanov, M.R.; Ludwig, K.F.; van der Voort, P.; Bals, S.; Detavernier, C. pdf  doi
openurl 
  Title Tuning the pore size of ink-bottle mesopores by atomic layer deposition Type A1 Journal article
  Year 2012 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 24 Issue 11 Pages 1992-1994  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos (up) 000305092600002 Publication Date 2012-05-03  
  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 52 Open Access  
  Notes Fwo Approved Most recent IF: 9.466; 2012 IF: 8.238  
  Call Number UA @ lucian @ c:irua:99078 Serial 3760  
Permanent link to this record
 

 
Author Khalilov, U.; Pourtois, G.; van Duin, A.C.T.; Neyts, E.C. doi  openurl
  Title Self-limiting oxidation in small-diameter Si nanowires Type A1 Journal article
  Year 2012 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 24 Issue 11 Pages 2141-2147  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Recently, core shell silicon nanowires (Si-NWs) have been envisaged to be used for field-effect transistors and photovoltaic applications. In spite of the constant downsizing of such devices, the formation of ultrasmall diameter core shell Si-NWs currently remains entirely unexplored. We report here on the modeling of the formation of such core shell Si-NWs using a dry thermal oxidation of 2 nm diameter (100) Si nanowires at 300 and 1273 K, by means of reactive molecular dynamics simulations using the ReaxFF potential. Two different oxidation mechanisms are discussed, namely a self-limiting process that occurs at low temperature (300 K), resulting in a Si core I ultrathin SiO2 silica shell nanowire, and a complete oxidation process that takes place at a higher temperature (1273 K), resulting in the formation of an ultrathin SiO2 silica nanowire. The oxidation kinetics of both cases and the resulting structures are analyzed in detail. Our results demonstrate that precise control over the Si-core radius of such NWs and the SiOx (x <= 2.0) oxide shell is possible by controlling the growth temperature used during the oxidation process.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos (up) 000305092600021 Publication Date 2012-05-18  
  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 45 Open Access  
  Notes Approved Most recent IF: 9.466; 2012 IF: 8.238  
  Call Number UA @ lucian @ c:irua:99079 Serial 2976  
Permanent link to this record
 

 
Author Čukarić, N.; Arsoski, V.; Tadić, M.; Peeters, F.M. url  doi
openurl 
  Title Hole states in nanocups in a magnetic field Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 85 Issue 23 Pages 235425-235425,11  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The magnetic-field dependence of the hole states in a nanocup, which is composed of a ring (the nanocup rim) that surrounds a disk (the nanocup bottom), is obtained within the Luttinger-Kohn model for the unstrained GaAs/(Al,Ga) As and the strained (In,Ga) As/GaAs systems. Aharonov-Bohm oscillations due to angular momentum transitions of the hole ground state appear with periods that vary with the thickness of the disk. The strain in the (In, Ga) As/GaAs nanocup is sensitive to the disk thickness and favors the spatial localization of the heavy holes inside the disk. Therefore, the angular momentum transitions between the valence-band states disappear for much thinner disks than in the case of the unstrained GaAs/(Al, Ga) As nanocups. In both systems, the oscillations in the energy of the hole ground state are found to disappear for thinner inner layer than in the electron ground-state energy. This is due to the different confining potentials and the mixing between the heavy- and light-hole states. As a consequence, magnetization of the single hole is found to strongly depend on the bottom thickness of the strained (In, Ga) As/GaAs nanocup. Furthermore, we found that the strain can lead to a spatial separation of the electron and the hole, as in type-II band alignment, which is advantageous for the appearance of the excitonic Aharonov-Bohm effect.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000305116700005 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 4 Open Access  
  Notes ; The authors thank B. Partoens for useful discussions. This work was supported by the EU NoE: SANDiE, the Ministry of Education and Science of Serbia, and the Belgian Science Policy (IAP). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:98906 Serial 1477  
Permanent link to this record
 

 
Author Chen, Y.; Shanenko, A.A.; Peeters, F.M. url  doi
openurl 
  Title Superconducting transition temperature of Pb nanofilms : impact of thickness-dependent oscillations of the phonon-mediated electron-electron coupling Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 85 Issue 22 Pages 224517-224517,6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract To date, several experimental groups reported measurements of the thickness dependence of T-c of atomically uniform single-crystalline Pb nanofilms. The reported amplitude of the T-c oscillations varies significantly from one experiment to another. Here we propose that the reason for this unresolved issue is an interplay of the quantum-size variations in the single-electron density of states with thickness-dependent oscillations in the phonon-mediated electron-electron coupling. Such oscillations in the coupling depend on the substrate material, the quality of the interface, the protection cover, and other details of the fabrication process, changing from one experiment to another. This explains why the available data do not exhibit one-voice consistency about the amplitude of the T-c oscillations. Our analyses are based on a numerical solution of the Bogoliubov-de Gennes equations for a superconducting slab.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000305251300006 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 24 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:99076 Serial 3368  
Permanent link to this record
 

 
Author Zarenia, M.; Vasilopoulos, P.; Peeters, F.M. url  doi
openurl 
  Title Magnetotransport in periodically modulated bilayer graphene Type A1 Journal article
  Year 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 (up) 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  
Permanent link to this record
 

 
Author Tsirlin, A.A.; Abakumov, A.M.; Ritter, C.; Henry, P.F.; Janson, O.; Rosner, H. url  doi
openurl 
  Title Short-range order of Br and three-dimensional magnetism in (CuBr)LaNb2O7 Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 85 Issue 21 Pages 214427  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We present a comprehensive study of the crystal structure, magnetic structure, and microscopic magnetic model of (CuBr)LaNb2O7, the Br analog of the spin-gap quantum magnet (CuCl) LaNb2O7. Despite similar crystal structures and spin lattices, the magnetic behavior and even peculiarities of the atomic arrangement in the Cl and Br compounds are very different. The high- resolution x-ray and neutron data reveal a split position of Br atoms in (CuBr) LaNb2O7. This splitting originates from two possible configurations developed by [CuBr] zigzag ribbons. While the Br atoms are locally ordered in the ab plane, their arrangement along the c direction remains partially disordered. The predominant and energetically more favorable configuration features an additional doubling of the c lattice parameter that was not observed in (CuCl) LaNb2O7. (CuBr) LaNb2O7 undergoes long-range antiferromagnetic ordering at T-N = 32 K, which is nearly 70% of the leading exchange coupling J4 similar or equal to 48 K. The Br compound does not show any experimental signatures of low-dimensional magnetism because the underlying spin lattice is three-dimensional. The coupling along the c direction is comparable to the couplings in the ab plane, even though the shortest Cu-Cu distance along c (11.69 angstrom) is three times larger than nearest-neighbor distances in the ab plane (3.55 angstrom). The stripe antiferromagnetic long-range order featuring columns of parallel spins in the ab plane and antiparallel spins along c is verified experimentally and confirmed by the microscopic analysis.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000305557600002 Publication Date 2012-06-22  
  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 5 Open Access  
  Notes Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:100289 Serial 2998  
Permanent link to this record
 

 
Author Navío, C.; Vallejos, S.; Stoycheva, T.; Llobet, E.; Correig, X.; Snyders, R.; Blackman, C.; Umek, P.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.; pdf  doi
openurl 
  Title Gold clusters on WO3 nanoneedles grown via AACVD : XPS and TEM studies Type A1 Journal article
  Year 2012 Publication Materials chemistry and physics Abbreviated Journal Mater Chem Phys  
  Volume 134 Issue 2/3 Pages 809-813  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract We have prepared tungsten oxide films decorated with gold particles on Si substrates by aerosol assisted chemical vapor deposition (AACVD) and characterized them using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). SEM shows that the films are composed of needle-like structures and TEM shows that both the needles and the gold particles are crystalline. XPS indicates the presence of oxygen vacancies, i.e. the films are WO3−x, and hence the deposited material is composed of semiconducting nanostructures and that the interaction between the gold particles and the WO3 needles surface is weak. The synthesis of semiconducting tungsten oxide nanostructures decorated with metal particles represents an important step towards the development of sensing devices with optimal properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lausanne Editor  
  Language Wos (up) 000305918200038 Publication Date 2012-04-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0254-0584; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.084 Times cited 52 Open Access  
  Notes Iap Approved Most recent IF: 2.084; 2012 IF: 2.072  
  Call Number UA @ lucian @ c:irua:97705 Serial 1356  
Permanent link to this record
 

 
Author Lizin, S.; Van Passel, S.; De Schepper, E.; Vranken, L. doi  openurl
  Title The future of organic photovoltaic solar cells as a direct power source for consumer electronics Type A1 Journal article
  Year 2012 Publication Solar Energy Materials And Solar Cells Abbreviated Journal Sol Energ Mat Sol C  
  Volume 103 Issue Pages 1-10  
  Keywords A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM)  
  Abstract As the search for marketable photovoltaic solar cells continues, organic photovoltaic (OPV) solar cells have been identified as a technology with many attractive features for commercialization. Most photovoltaic technologies on the market today were improved in the consumer electronics market segment. A similar evolution has been envisioned for OPV. Hence this paper investigates consumer preferences for solar cells directly powering consumer electronics. Choice experiments were designed and responses were collected using a random sample of 300 individuals from the Flemish region (northern part of Belgium). Results allow for computation of attribute importance, willingness to pay (WTP), and simulation of theoretical market share. These measures point towards OPV being able to reach considerable market share in the long run, bearing in mind that efforts are first needed in elevating OPV's efficiency and lifetime as they most determine consumers' preferences. Price is found to be the least important product characteristic for OPV solar cells to be incorporated in consumer electronics devices. We therefore warn against generalizing attributes' importance across the boundaries of market segments. (C) 2012 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000306044300001 Publication Date 2012-05-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0927-0248 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.784 Times cited 25 Open Access  
  Notes ; The authors would kindly want to express their gratitude towards every survey respondent and participant for their preliminary work. Also the authors are much obliged to INTERREG and the ORGANEXT project for their financial support, without which it would have been impossible to conduct this research. Last but not least, we would like to thank the reviewers for their insightful comments which allowed for fine tuning our work. ; Approved Most recent IF: 4.784; 2012 IF: 4.630  
  Call Number UA @ admin @ c:irua:127556 Serial 6267  
Permanent link to this record
 

 
Author Pina, J.C.; de Souza Silva, C.C.; Milošević, M.V. url  doi
openurl 
  Title Stability of fractional vortex states in a two-band mesoscopic superconductor Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 86 Issue 2 Pages 024512  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We investigate the stability of noncomposite fractional vortex states in a mesoscopic two-band superconductor within the two-component Ginzburg-Landau model. Our analysis explicitly takes into account the relationship between the model parameters and microscopic material parameters, such as partial density of states, Fermi velocities and elements of the electron-phonon coupling matrix. We have found that states with different phase winding number in each band (L-1 not equal L-2) and fractional flux can exist in many different configurations, including rather unconventional ones where the dominating band carries larger winding number and states where vertical bar L-1 – L-2 vertical bar > 1. We present a detailed analysis of the stability of the observed vortex structures with respect to changing the microscopic parameters, showing that, in the weak coupling case, fractional vortex states can be assessed in essentially the whole range of temperatures and applied magnetic fields in which both bands are active. Finally, we propose an efficient way of increasing the range of parameters for which these fractional vortex states can be stabilized. In particular, our proposal allows for observation of fractional vortex structures in materials with stronger coupling, where those states are forbidden at a homogeneous field. This is accomplished with the help of the stray fields of a suitably prepared magnetic dot placed nearby the superconducting disk.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos (up) 000306309600006 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 38 Open Access  
  Notes ; We thank Eric B. Claude, Miguel A. Zorro, and Rogerio M. da Silva for assistance in the development of the numerical code used in our simulations. This work was supported by the Brazilian science agencies CNPq and FACEPE, by the FACEPE/CNPq-PRONEX program, under Grant No. APQ-0589-1.05/08, and by CNPq-FWO Brazil-Flanders co-operation program. M.V.M. acknowledges support from the CAPES-PVE program. ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:100766 Serial 3126  
Permanent link to this record
 

 
Author Neek-Amal, M.; Covaci, L.; Peeters, F.M. url  doi
openurl 
  Title Nanoengineered nonuniform strain in graphene using nanopillars Type A1 Journal article
  Year 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 (up) 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  
Permanent link to this record
 

 
Author Costamagna, S.; Neek-Amal, M.; Los, J.H.; Peeters, F.M. url  doi
openurl 
  Title Thermal rippling behavior of graphane Type A1 Journal article
  Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 86 Issue 4 Pages 041408-4  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Thermal fluctuations of single layer hydrogenated graphene (graphane) are investigated using large scale atomistic simulations. By analyzing the mean square value of the height fluctuations < h(2)> and the height-height correlation function H(q) for different system sizes and temperatures, we show that hydrogenated graphene is an unrippled system in contrast to graphene. The height fluctuations are bounded, which is confirmed by a H(q) tending to a constant in the long wavelength limit instead of showing the characteristic scaling law q(4-eta)(eta similar or equal to 0.85) predicted by membrane theory. This unexpected behavior persists up to temperatures of at least 900 K and is a consequence of the fact that in graphane the thermal energy can be accommodated by in-plane bending modes, i.e., modes involving C-C-C bond angles in the buckled carbon layer, instead of leading to significant out-of-plane fluctuations that occur in graphene.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos (up) 000306649200002 Publication Date 2012-07-23  
  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 46 Open Access  
  Notes ; We thank A. Fasolino, A. Dobry, and K. H. Michel for their useful comments. S.C. is supported by the Belgian Science Foundation (BELSPO). This work is supported by the ESF-EuroGRAPHENE project CONGRAN and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2012 IF: 3.767  
  Call Number UA @ lucian @ c:irua:100840 Serial 3630  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: