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Author Nishio, K.; Lu, A.K.A.; Pourtois, G. url  doi
openurl 
  Title Low-strain Si/O superlattices with tunable electronic properties : ab initio calculations Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 91 Issue 91 Pages 165303  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract (up) We propose that low-strain Si/O superlattices can be constructed by connecting reconstructed Si{001} surfaces by Si-O-Si bridges. Ab initio calculations show that our models are energetically more favorable than all the models proposed so far. The part of our Si/O superlattice model is experimentally accessible just by oxidizing a Si( 001) substrate. To complete our Si/O superlattice model, we propose a three-step method. We also explore the potential of our Si/O superlattice models for new materials used in future Si electronics. We find that the location of the channel where the carriers travel can be controlled between the interfaces and the Si layers by the insertion of O atoms into the Si-Si dimers. By revealing the origins of the interface electron and hole states, we find that similar interface states should be easily achieved for Si slabs and Si substrates. Interestingly, the interface electrons and holes have small effective masses in the direction parallel to the channel and large effective masses in the direction normal to the channel, which makes the Si/O superlattices attractive to be used for channel materials. We also find that the valley splitting of Si is enhanced by the formation of the Si/O/Si interfaces, which is ideal for developing Si-based qubits. Our findings open new perspectives to design and control the electronic properties of Si.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000352986700002 Publication Date 2015-04-16  
  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 6 Open Access  
  Notes Approved Most recent IF: 3.836; 2015 IF: 3.736  
  Call Number c:irua:125998 Serial 1852  
Permanent link to this record
 

 
Author Ghosh, S.; Gaspari, R.; Bertoni, G.; Spadaro, M.C.; Prato, M.; Turner, S.; Cavalli, A.; Manna, L.; Brescia, R. pdf  url
doi  openurl
  Title Pyramid-Shaped Wurtzite CdSe Nanocrystals with Inverted Polarity Type A1 Journal article
  Year 2015 Publication ACS nano Abbreviated Journal Acs Nano  
  Volume 9 Issue 9 Pages 8537-8546  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract (up) We report on pyramid-shaped wurtzite cadmium selenide (CdSe) nanocrystals (NCs), synthesized by hot injection in the presence of chloride ions as shape-directing agents, exhibiting reversed crystal polarity compared to former reports. Advanced transmission electron microscopy (TEM) techniques (image-corrected high-resolution TEM with exit wave reconstruction and probe-corrected high-angle annular dark field-scanning TEM) unequivocally indicate that the triangular base of the pyramids is the polar (0001) facet and their apex points toward the [0001] direction. Density functional theory calculations, based on a simple model of binding of Cl(-) ions to surface Cd atoms, support the experimentally evident higher thermodynamic stability of the (0001) facet over the (0001) one conferred by Cl(-) ions. The relative stability of the two polar facets of wurtzite CdSe is reversed compared to previous experimental and computational studies on Cd chalcogenide NCs, in which no Cl-based chemicals were deliberately used in the synthesis or no Cl(-) ions were considered in the binding models. Self-assembly of these pyramids in a peculiar clover-like geometry, triggered by the addition of oleic acid, suggests that the basal (polar) facet has a density and perhaps type of ligands significantly different from the other three facets, since the pyramids interact with each other exclusively via their lateral facets. A superstructure, however with no long-range order, is observed for clovers with their (0001) facets roughly facing each other. The CdSe pyramids were also exploited as seeds for CdS pods growth, and the peculiar shape of the derived branched nanostructures clearly arises from the inverted polarity of the seeds.  
  Address Department of Nanochemistry, Istituto Italiano di Tecnologia (IIT) , via Morego 30, I-16163 Genova, Italy  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Wos 000360323300085 Publication Date 2015-07-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 13.942 Times cited 16 Open Access  
  Notes PMID:26203791 Approved Most recent IF: 13.942; 2015 IF: 12.881  
  Call Number c:irua:127807 Serial 3956  
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Author Barreca, D.; Carraro, G.; Gasparotto, A.; Maccato, C.; Warwick, M.E.A.; Turner, S.; Van Tendeloo, G. pdf  doi
openurl 
  Title Fabrication and Characterization of Fe2O3-Based Nanostructures Functionalized with Metal Particles and Oxide Overlayers Type A1 Journal article
  Year 2015 Publication Journal of advanced microscopy research Abbreviated Journal  
  Volume 10 Issue 10 Pages 239-243  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract (up) We report on the design of nanosystems based on functionalized -Fe 2 O 3 nanostructures supported on fluorine-doped tin oxide (FTO) substrates. The target materials were developed by means of hybrid vapor phase approaches, combining plasma assisted-chemical vapor deposition (PA-CVD) for the production of iron(III) oxide systems and the subsequent radio frequency (RF)-sputtering or atomic layer deposition (ALD) for the functionalization with Au nanoparticles or TiO 2 overlayers, respectively. The interplay between material characteristics and the adopted processing parameters was investigated by complementary analytical techniques, encompassing X-ray photoelectron spectroscopy (XPS), field emission-scanning electron microscopy (FE-SEM), high angle annular dark field-scanning transmission electron microscopy (HAADF-STEM), and energy dispersive X-ray spectroscopy (EDXS). The obtained results highlight the possibility of fabricating Au/ -Fe 2 O 3 nanocomposites, with a controlled dispersion and distribution of metal particles, and TiO 2 / -Fe 2 O 3 heterostructures, characterized by an intimate coupling between the constituent oxides.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 2015-12-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2156-7573 ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes The authors acknowledge the financial support under the FP7 project “SOLARO- GENIX” (NMP4-SL-2012-310333), as well as Padova University ex-60% 2012–2015 projects, grant n CPDR132937/13 (SOLLEONE), and Regione Lombardia- INSTM ATLANTE program. Stuart Turner acknowledges the FWO Flanders for a post-doctoral scholarship. Thanks are also due to Dr. L. Borgese and Prof. E. Bontempi (Chemistry for Technologies Laboratory, Brescia Univer- sity, Italy) for precious assistance in ALD experiments. Approved Most recent IF: NA  
  Call Number EMAT @ emat @ c:irua:132798 Serial 4058  
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Author Oueslati, S.; Brammertz, G.; Buffiere, M.; ElAnzeery, H.; Touayar, O.; Koeble, C.; Bekaert, J.; Meuris, M.; Poortmans, J. pdf  doi
openurl 
  Title Physical and electrical characterization of high-performance Cu2ZnSnSe4 based thin film solar cells Type A1 Journal article
  Year 2015 Publication Thin solid films : an international journal on the science and technology of thin and thick films Abbreviated Journal Thin Solid Films  
  Volume 582 Issue 582 Pages 224-228  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) We report on the electrical, optical and physical properties of Cu2ZnSnSe4 solar cells using an absorber layer fabricated by selenization of sputtered Cu, Zn and Cu10Sn90 multilayers. A maximum active-area conversion efficiency of 10.4% under AM1.5G was measured with a maximum short circuit current density of 39.7 mA/cm(2), an open circuit voltage of 394 mV and a fill factor of 66.4%. We perform electrical and optical characterization using photoluminescence spectroscopy, external quantum efficiency, current-voltage and admittance versus temperature measurements in order to derive information about possible causes for the low open circuit voltage values observed. The main defects derived from these measurements are strong potential fluctuations in the absorber layer as well as a potential barrier of the order of 133 meV at the back side contact. (C) 2014 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lausanne Editor  
  Language Wos 000352225900048 Publication Date 2014-10-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0040-6090 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.879 Times cited 49 Open Access  
  Notes ; We would like to acknowledge Tom De Geyter, Greetje Godiers, and Guido Huyberechts from Flamac in Gent for sputtering of the metal layers. AGC is acknowledged for providing substrates. This research is partially funded by the Flemish government, Department Economy, Science and Innovation. ; Approved Most recent IF: 1.879; 2015 IF: 1.759  
  Call Number UA @ lucian @ c:irua:132504 Serial 4225  
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Author Clima, S.; Chen, Y.Y.; Fantini, A.; Goux, L.; Degraeve, R.; Govoreanu, B.; Pourtois, G.; Jurczak, M. doi  openurl
  Title Intrinsic tailing of resistive states distributions in amorphous <tex>HfOx </tex> and TaOx based resistive random access memories Type A1 Journal article
  Year 2015 Publication IEEE electron device letters Abbreviated Journal Ieee Electr Device L  
  Volume 36 Issue 36 Pages 769-771  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract (up) We report on the ineffectiveness of programming oxide-based resistive random access memory (OxRAM) at low current with a program and verify algorithm due to intrinsic relaxation of the verified distribution to the natural state distribution obtained by single-pulse programming without verify process. Based on oxygen defect formation thermodynamics and on their diffusion barriers in amorphous HfOx and TaOx, we describe the intrinsic nature of tailing of the verified low resistive state and high resistive state distributions. We introduce different scenarios to explain fast distribution widening phenomenon, which is a fundamental limitation for OxRAM current scaling and device reliability.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000358570300011 Publication Date 2015-06-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0741-3106 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.048 Times cited 33 Open Access  
  Notes Approved Most recent IF: 3.048; 2015 IF: 2.754  
  Call Number UA @ lucian @ c:irua:134412 Serial 4200  
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Author Euan-Diaz, E.; Herrera-Velarde, S.; Misko, V.R.; Peeters, F.M.; Castaneda-Priego, R. doi  openurl
  Title Structural transitions and long-time self-diffusion of interacting colloids confined by a parabolic potential Type A1 Journal article
  Year 2015 Publication The journal of chemical physics Abbreviated Journal J Chem Phys  
  Volume 142 Issue 142 Pages 024902  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) We report on the ordering and dynamics of interacting colloidal particles confined by a parabolic potential. By means of Brownian dynamics simulations, we find that by varying the magnitude of the trap stiffness, it is possible to control the dimension of the system and, thus, explore both the structural transitions and the long-time self-diffusion coefficient as a function of the degree of confinement. We particularly study the structural ordering in the directions perpendicular and parallel to the confinement. Further analysis of the local distribution of the first-neighbors layer allows us to identify the different structural phases induced by the parabolic potential. These results are summarized in a structural state diagram that describes the way in which the colloidal suspension undergoes a structural re-ordering while increasing the confinement. To fully understand the particle dynamics, we take into account hydrodynamic interactions between colloids; the parabolic potential constricts the available space for the colloids, but it does not act on the solvent. Our findings show a non-linear behavior of the long-time self-diffusion coefficient that is associated to the structural transitions induced by the external field. (C) 2015 AIP Publishing LLC.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000348129700053 Publication Date 2015-01-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-9606;1089-7690; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.965 Times cited 7 Open Access  
  Notes ; This work was partially supported by the “Odysseus” Program of the Flemish Government, the Flemish Science Foundation (FWO-Vl), PIFI 3.4 – PROMEP, and CONACyT (Grant Nos. 61418/2007, 102339/2008, Ph.D. scholarship 230171/2010). R.C.-P. also acknowledges financial support provided by the Marcos Moshinsky fellowship 2013-2014. The authors also thank to the General Coordination of Information and Communications Technologies (CGSTIC) at Cinvestav for providing HPC resources on the Hybrid Cluster Super-computer Xiuhcoatl, which have contributed partially to the research results reported in this paper. ; Approved Most recent IF: 2.965; 2015 IF: 2.952  
  Call Number c:irua:123832 Serial 3267  
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Author Kuopanportti, P.; Orlova, N.V.; Milošević, M.V. url  doi
openurl 
  Title Ground-state multiquantum vortices in rotating two-species superfluids Type A1 Journal article
  Year 2015 Publication Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A  
  Volume 91 Issue 91 Pages 043605  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) We show numerically that a rotating, harmonically trapped mixture of two Bose-Einstein-condensed superfluids cancontrary to its single-species counterpartcontain a multiply quantized vortex in the ground state of the system. This giant vortex can occur without any accompanying single-quantum vortices, may either be coreless or have an empty core, and can be realized in a Rb87−K41 Bose-Einstein condensate. Our results not only provide a rare example of a stable, solitary multiquantum vortex but also reveal exotic physics stemming from the coexistence of multiple, compositionally distinct condensates in one system.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000352255200005 Publication Date 2015-04-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.925 Times cited 25 Open Access  
  Notes ; This work was supported by the Finnish Cultural Foundation, the Research Foundation – Flanders (FWO), and the Magnus Ehrnrooth Foundation. We thank E. Ruokokoski and T. P. Simula for valuable comments and discussions. ; Approved Most recent IF: 2.925; 2015 IF: 2.808  
  Call Number c:irua:124906 Serial 1388  
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Author Missault, N.; Vasilopoulos, P.; Vargiamidis, V.; Peeters, F.M.; Van Duppen, B. url  doi
openurl 
  Title Spin- and valley-dependent transport through arrays of ferromagnetic silicene junctions Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 92 Issue 92 Pages 195423  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) We study ballistic transport of Dirac fermions in silicene through arrays of barriers, of width d, in the presence of an exchange field M and a tunable potential of height U or depth-U. The spin-and valley-resolved conductances as functions of U or M, exhibit resonances away from the Dirac point (DP) and close to it a pronounced dip that becomes a gap when a critical electric field E-z is applied. This gap widens by increasing the number of barriers and can be used to realize electric field-controlled switching of the current. The spin p(s) and valley p(v) polarizations of the current near the DP increase with Ez or M and can reach 100% for certain of their values. These field ranges widen significantly by increasing the number of barriers. Also, ps and pv oscillate nearly periodically with the separation between barriers or wells and can be inverted by reversing M.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000364998100006 Publication Date 2015-11-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121; 1550-235x ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 54 Open Access  
  Notes ; This work was supported by the Canadian NSERC Grant No. OGP0121756 (P.V.) and by the Flemish Science Foundation (FWO-Vl) with a Ph.D. research grant (B.V.D.). ; Approved Most recent IF: 3.836; 2015 IF: 3.736  
  Call Number UA @ lucian @ c:irua:130264 Serial 4247  
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Author Moldovan, D.; Peeters, F.M. pdf  url
doi  openurl
  Title Strain engineering of the electronic properties of bilayer graphene quantum dots: Strain engineering of the electronic properties of bilayer graphene quantum dots Type A1 Journal article
  Year 2015 Publication Physica status solidi: rapid research letters Abbreviated Journal Phys Status Solidi-R  
  Volume 10 Issue 10 Pages 39-45  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) We study the effect of mechanical deformations on the elec- tronic properties of hexagonal flakes of bilayer graphene. The behavior of electrons induced by triaxial strain can be de- scribed by an effective pseudo-magnetic field which is homo- geneous in the center of the flake. We find that in-plane strain, applied to both layers equally, can break the layer symmetry leading to different behavior in the top and bottom layers of graphene. At low energy, just one of the layers feels

the pseudo-magnetic field: the zero-energy pseudo-Landau level is missing in the second layer, thus creating a gap be- tween the lowest non-zero levels. While the layer asymmetry is most significant at zero energy, interaction with the edges of the flake extends the effect to higher pseudo-Landau lev- els. The behavior of the top and bottom layers may be re- versed by rotating the triaxial strain by 60°.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000368814500005 Publication Date 2015-08-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1862-6254; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.032 Times cited 9 Open Access  
  Notes This work was supported by the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN, the Flemish Science Foundation (FWO-Vl) and the Methusalem Funding of the Flemish Government. Approved Most recent IF: 3.032; 2015 IF: 2.142  
  Call Number c:irua:129592 Serial 3970  
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Author de de Meux, A.J.; Pourtois, G.; Genoe, J.; Heremans, P. pdf  doi
openurl 
  Title Comparison of the electronic structure of amorphous versus crystalline indium gallium zinc oxide semiconductor : structure, tail states and strain effects Type A1 Journal article
  Year 2015 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys  
  Volume 48 Issue 48 Pages 435104  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract (up) We study the evolution of the structural and electronic properties of crystalline indium gallium zinc oxide (IGZO) upon amorphization by first-principles calculation. The bottom of the conduction band (BCB) is found to be constituted of a pseudo-band of molecular orbitals that resonate at the same energy on different atomic sites. They display a bonding character between the s orbitals of the metal sites and an anti-bonding character arising from the interaction between the oxygen and metal s orbitals. The energy level of the BCB shifts upon breaking of the crystal symmetry during the amorphization process, which may be attributed to the reduction of the coordination of the cationic centers. The top of the valence band (TVB) is constructed from anti-bonding oxygen p orbitals. In the amorphous state, they have random orientation, in contrast to the crystalline state. This results in the appearance of localized tail states in the forbidden gap above the TVB. Zinc is found to play a predominant role in the generation of these tail states, while gallium hinders their formation. Last, we study the dependence of the fundamental gap and effective mass of IGZO on mechanical strain. The variation of the gap under strain arises from the enhancement of the anti-bonding interaction in the BCB due to the modification of the length of the oxygen-metal bonds and/or to a variation of the cation coordination. This effect is less pronounced for the amorphous material compared to the crystalline material, making amorphous IGZO a semiconductor of choice for flexible electronics. Finally, the effective mass is found to increase upon strain, in contrast to regular materials. This counterintuitive variation is due to the reduction of the electrostatic shielding of the cationic centers by oxygen, leading to an increase of the overlaps between the metal orbitals at the origin of the delocalization of the BCB. For the range of strain typically met in flexible electronics, the induced variation in the effective mass is found to be negligible (less than 1%).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000365876300012 Publication Date 2015-09-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-3727 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.588 Times cited 23 Open Access  
  Notes Approved Most recent IF: 2.588; 2015 IF: 2.721  
  Call Number UA @ lucian @ c:irua:130277 Serial 4153  
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Author Croitoru, M.D.; Buzdin, A.I. pdf  doi
openurl 
  Title FFLO-wave-vector lock-in effect in quasi-1D superconductors Type A1 Journal article
  Year 2015 Publication Journal of superconductivity and novel magnetism Abbreviated Journal J Supercond Nov Magn  
  Volume 28 Issue 28 Pages 1305-1308  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) We study the phase transition into the Fulde-Ferrell-Larkin-Ovchinnikov state in high magnetic field in quasi-one dimensional superconductors within the quasi-classical formalism, taking into account the interchain Josephson coupling and the paramagnetic spin splitting. We show that anomalies in the field-direction dependence of the upper critical field when the magnetic field length equals to the FFLO period, previously described in [29], are characterized by the lock-in effect of the FFLO modulation wave vector, which is governed by the magnetic length.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000352085700019 Publication Date 2014-12-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1557-1939;1557-1947; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.18 Times cited 4 Open Access  
  Notes ; We thank D. Jerome for useful discussions. We acknowledge the support by the French ANR program “ElectroVortex” and European NanoSC COST Action MP1201. M.D.C. acknowledges the support by the BELSPO Return to Belgium Grant. ; Approved Most recent IF: 1.18; 2015 IF: 0.909  
  Call Number c:irua:125540 Serial 1187  
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Author Zalipaev, V.; Linton, C.M.; Croitoru, M.D.; Vagov, A. url  doi
openurl 
  Title Resonant tunneling and localized states in a graphene monolayer with a mass gap Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 91 Issue 91 Pages 085405  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) We study tunneling of quasiparticles through potential barriers in a graphene monolayer with the mass gap using a semiclassical (WKB) approach. The main equations are derived in away similar to the WKB theory for the Schrodinger equation, which allows for explicit solutions at all orders. The analog of the classical action is used to distinguish types of possible stationary states in the system. The analysis focuses on the resonant scattering and the hole states localized in the vicinity of a barrier that are often overlooked. The scattering coefficients for the physically interesting limits are obtained by matching the WKB approximation with the known solutions at turning points. The localized states demonstrate unconventional properties and lead to alterations of the single particle density of states.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000351773900004 Publication Date 2015-02-05  
  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 3 Open Access  
  Notes ; M.D.C. acknowledges the Belgian Science Policy (BELSPO Back to Belgium Grant). ; Approved Most recent IF: 3.836; 2015 IF: 3.736  
  Call Number c:irua:125523 Serial 2891  
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Author de Sousa, A.A.; Chaves, A.; Pereira, T.A.S.; Farias, G.A.; Peeters, F.M. doi  openurl
  Title Quantum tunneling between bent semiconductor nanowires Type A1 Journal article
  Year 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 118 Issue 118 Pages 174301  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) We theoretically investigate the electronic transport properties of two closely spaced L-shaped semiconductor quantum wires, for different configurations of the output channel widths as well as the distance between the wires. Within the effective-mass approximation, we solve the time-dependent Schrodinger equation using the split-operator technique that allows us to calculate the transmission probability, the total probability current, the conductance, and the wave function scattering between the energy subbands. We determine the maximum distance between the quantum wires below which a relevant non-zero transmission is still found. The transmission probability and the conductance show a strong dependence on the width of the output channel for small distances between the wires. (C) 2015 AIP Publishing LLC.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000364584200020 Publication Date 2015-11-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 7 Open Access  
  Notes ; A. A. Sousa was financially supported by CAPES, under the PDSE Contract No. BEX 7177/13-5. T. A. S. Pereira was financially supported by PRONEX/CNPq/FAPEMAT 850109/2009 and by CAPES under process BEX 3299/13-9. This work was financially supported by PRONEX/CNPq/FUNCAP, the Science Without Borders program and the bilateral project CNPq-FWO. ; Approved Most recent IF: 2.068; 2015 IF: 2.183  
  Call Number UA @ lucian @ c:irua:129544 Serial 4234  
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Author Kozák, T.; Bogaerts, A. pdf  url
doi  openurl
  Title Evaluation of the energy efficiency of CO2 conversion in microwave discharges using a reaction kinetics model Type A1 Journal article
  Year 2015 Publication Plasma sources science and technology Abbreviated Journal Plasma Sources Sci T  
  Volume 24 Issue 24 Pages 015024  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract (up) We use a zero-dimensional reaction kinetics model to simulate CO2 conversion in microwave discharges where the excitation of the vibrational levels plays a significant role in the dissociation kinetics. The model includes a description of the CO2 vibrational kinetics, taking into account state-specific VT and VV relaxation reactions and the effect of vibrational excitation on other chemical reactions. The model is used to simulate a general tubular microwave reactor, where a stream of CO2 flows through a plasma column generated by microwave radiation. We study the effects of the internal plasma parameters, namely the reduced electric field, electron density and the total specific energy input, on the CO2 conversion and its energy efficiency. We report the highest energy efficiency (up to 30%) for a specific energy input in the range 0.41.0 eV/molecule and a reduced electric field in the range 50100 Td and for high values of the electron density (an ionization degree greater than 10−5). The energy efficiency is mainly limited by the VT relaxation which contributes dominantly to the vibrational energy losses and also contributes significantly to the heating of the reacting gas. The model analysis provides useful insight into the potential and limitations of CO2 conversion in microwave discharges.  
  Address  
  Corporate Author Thesis  
  Publisher Institute of Physics Place of Publication Bristol Editor  
  Language Wos 000348298200025 Publication Date 2014-12-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0963-0252;1361-6595; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.302 Times cited 100 Open Access  
  Notes Approved Most recent IF: 3.302; 2015 IF: 3.591  
  Call Number c:irua:122243 Serial 1087  
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Author Becker, T.; Nelissen, K.; Cleuren, B. pdf  doi
openurl 
  Title Current fluctuations in boundary driven diffusive systems in different dimensions : a numerical study Type A1 Journal article
  Year 2015 Publication New journal of physics Abbreviated Journal New J Phys  
  Volume 17 Issue 17 Pages 055023  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) We use kinetic Monte Carlo simulations to investigate current fluctuations in boundary driven generalized exclusion processes, in different dimensions. Simulation results are in full agreement with predictions based on the additivity principle and the macroscopic fluctuation theory. The current statistics are independent of the shape of the contacts with the reservoirs, provided they are macroscopic in size. In general, the current distribution depends on the spatial dimension. For the special cases of the symmetric simple exclusion process and the zero-range process, the current statistics are the same for all spatial dimensions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000355282700001 Publication Date 2015-05-27  
  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 5 Open Access  
  Notes ; We thank Christian Van den Broeck for bringing this problem to our attention. We are grateful to Bart Partoens and Carlo Vanderzande for a careful reading of the manuscript. This work was supported by the Flemish Science Foundation (Fonds Wetenschappelijk Onderzoek), Project No. G038811N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government-department EWI. ; Approved Most recent IF: 3.786; 2015 IF: 3.558  
  Call Number c:irua:126405 Serial 592  
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Author Berdiyorov, G.R.; Savel'ev, S.; Kusmartsev, F.V.; Peeters, F.M. url  doi
openurl 
  Title Effect of ordered array of magnetic dots on the dynamics of Josephson vortices in stacked SNS Josephson junctions under DC and AC current Type A1 Journal article
  Year 2015 Publication European physical journal : B : condensed matter and complex systems Abbreviated Journal Eur Phys J B  
  Volume 88 Issue 88 Pages 286  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) We use the anisotropic time-dependent Ginzburg-Landau theory to investigate the effect of a square array of out-of-plane magnetic dots on the dynamics of Josephson vortices (fluxons) in artificial stacks of superconducting-normal-superconducting (SNS) Josephson junctions in the presence of external DC and AC currents. Periodic pinning due to the magnetic dots distorts the triangular lattice of fluxons and results in the appearance of commensurability features in the current-voltage characteristics of the system. For the larger values of the magnetization, additional peaks appear in the voltage-time characteristics of the system due to the creation and annihilation of vortex-antivortex pairs. Peculiar changes in the response of the system to the applied current is found resulting in a “superradiant” vortex-flow state at large current values, where a rectangular lattice of moving vortices is formed. Synchronizing the motion of fluxons by adding a small ac component to the biasing dc current is realized. However, we found that synchronization becomes difficult for large magnetization of the dots due to the formation of vortex-antivortex pairs.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Berlin Editor  
  Language Wos 000363960900002 Publication Date 2015-10-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1434-6028 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.461 Times cited 1 Open Access  
  Notes ; This work was supported by EU Marie Curie (Project No. 253057). ; Approved Most recent IF: 1.461; 2015 IF: 1.345  
  Call Number UA @ lucian @ c:irua:129509 Serial 4166  
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Author Van Hoey, S.; Nopens, I.; van der Kwast, J.; Seuntjens, P. doi  openurl
  Title Dynamic identifiability analysis-based model structure evaluation considering rating curve uncertainty Type A1 Journal article
  Year 2015 Publication Journal of hydrologic engineering Abbreviated Journal  
  Volume 20 Issue 5 Pages 04014072  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract (up) When applying hydrological models, different sources of uncertainty are present, and evaluations of model performances should take these into account to assess model outcomes correctly. Furthermore, uncertainty in the discharge observations complicates the model identification, both in terms of model structure and parameterization. In this paper, the authors compare two different lumped model structures (PDM and NAM) considering uncertainty coming from the rating curve. Limits of acceptability for the model simulations were determined based on derived uncertainty bounds of the discharge observations. The authors applied the DYNamic Identifiability Approach (DYNIA) to identify structural failure of both models and to evaluate the configuration of their structures. In general, similar model performances are observed. However, the model structures tend to behave differently in the course of time, as revealed by the DYNIA approach. Based on the analyses performed, the probability based soil storage representation of the PDM model outperforms the NAM structure. The incorporation of the observation error did not prevent the DYNIA analysis to identify potential model structural deficiencies that are limiting the representation of the seasonal variation, primarily indicated by shifting regions of parameter identifiability. As such, the proposed approach is able to indicate where deficiencies are found and model improvement is needed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000353995400002 Publication Date 2014-03-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1084-0699 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:126056 Serial 7829  
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Author Vasylenko, A.A.; Misko, V.R. pdf  doi
openurl 
  Title Nonlinear transport of the Wigner crystal in symmetric and asymmetric FET-like structures : nonlinear transport of the Wigner crystal on superfluid He-4 in quasi-one-dimensional channels with symmetric and asymmetric constrictions Type A1 Journal article
  Year 2015 Publication European physical journal : B : condensed matter and complex systems Abbreviated Journal Eur Phys J B  
  Volume 88 Issue 88 Pages 105  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) When floating on a two-dimensional surface of superfluid He-4, electrons arrange themselves in two-dimensional crystalline structure known as Wigner crystal. In channels, the boundaries interfere the crystalline order and in case of very narrow channels one observes a quasi-one-dimensional (quasi-1D) Wigner crystal formed by just a few rows of electrons and, ultimately, one row in the “quantum wire” regime. Recently, the “quantum wire” regime was accessed experimentally [D.G. Rees, H. Totsuji, K. Kono, Phys. Rev. Lett. 108, 176801 (2012)] resulting in unusual transport phenomena such as, e.g., oscillations in the electron conductance. Using molecular dynamics simulations, we study the nonlinear transport of electrons in channels with various types of constrictions: single and multiple symmetric and asymmetric geometrical constrictions with varying width and length, and saddle-point-type potentials with varying gate voltage. In particular, we analyze the average particle velocity of the particles and the corresponding electron current versus the driving force or the gate voltage. We have revealed a significant difference in the dynamics for long and short constrictions: The oscillations of the average velocity of the particles for the systems with short constrictions exhibit a clear correlation with the transitions between the states with different numbers of rows of particles; on the other hand, for the systems with longer constrictions these oscillations are suppressed. The obtained results qualitatively agree with the experimental observations. Next, we propose a FET-like structure that consists of a channel with asymmetric constrictions. We show that applying a transverse bias results either in increase of the average particle velocity or in its suppression thus allowing a flexible control tool over the electron transport. The advantage of the asymmetric FET is that it does not have a gate and it allows an easy control of relatively large electron flow. Furthermore, the asymmetric device can be used for rectification of an ac-driven electron flow. Our results bring important insights into the dynamics of electrons floating on the surface of superfluid He-4 in channels with constrictions and allow the effective control over the electron transport.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Berlin Editor  
  Language Wos 000353065100002 Publication Date 2015-04-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1434-6028;1434-6036; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.461 Times cited Open Access  
  Notes Approved Most recent IF: 1.461; 2015 IF: 1.345  
  Call Number c:irua:125997 Serial 2359  
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Author Neyts, E.C. pdf  doi
openurl 
  Title The role of ions in plasma catalytic carbon nanotube growth : a review Type A1 Journal article
  Year 2015 Publication Frontiers of Chemical Science and Engineering Abbreviated Journal Front Chem Sci Eng  
  Volume 9 Issue 9 Pages 154-162  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract (up) While it is well-known that the plasma-enhanced catalytic chemical vapor deposition (PECVD) of carbon nanotubes (CNTs) offers a number of advantages over thermal CVD, the influence of the various individual contributing factors is not well understood. Especially the role of ions is unclear, since ions in plasmas are generally associated with sputtering rather than with growing a material. Even so, various studies have demonstrated the beneficial effects of ion bombardment during the growth of CNTs. This review looks at the role of the ions in plasma-enhanced CNT growth as deduced from both experimental and simulation studies. Specific attention is paid to the beneficial effects of ion bombardment. Based on the available literature, it can be concluded that ions can be either beneficial or detrimental for carbon nanotube growth, depending on the exact conditions and the control over the growth process.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000360319600003 Publication Date 2015-06-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2095-0179 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.712 Times cited 8 Open Access  
  Notes Approved Most recent IF: 1.712; 2015 IF: NA  
  Call Number UA @ lucian @ c:irua:127815 Serial 4239  
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Author Van der Paal, J.; Verlackt, C.C.; Yusupov, M.; Neyts, E.C.; Bogaerts, A. pdf  url
doi  openurl
  Title Structural modification of the skin barrier by OH radicals : a reactive molecular dynamics study for plasma medicine Type A1 Journal article
  Year 2015 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys  
  Volume 48 Issue 48 Pages 155202  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract (up) While plasma treatment of skin diseases and wound healing has been proven highly effective, the underlying mechanisms, and more generally the effect of plasma radicals on skin tissue, are not yet completely understood. In this paper, we perform ReaxFF-based reactive molecular dynamics simulations to investigate the interaction of plasma generated OH radicals with a model system composed of free fatty acids, ceramides, and cholesterol molecules. This model system is an approximation of the upper layer of the skin (stratum corneum). All interaction mechanisms observed in our simulations are initiated by H-abstraction from one of the ceramides. This reaction, in turn, often starts a cascade of other reactions, which eventually lead to the formation of aldehydes, the dissociation of ceramides or the elimination of formaldehyde, and thus eventually to the degradation of the skin barrier function.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000351856600007 Publication Date 2015-03-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-3727;1361-6463; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.588 Times cited 20 Open Access  
  Notes Approved Most recent IF: 2.588; 2015 IF: 2.721  
  Call Number c:irua:124230 Serial 3242  
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Author Delmelle, R.; Amin-Ahmadi, B.; Sinnaeve, M.; Idrissi, H.; Pardoen, T.; Schryvers, D.; Proost, J. pdf  url
doi  openurl
  Title Effect of structural defects on the hydriding kinetics of nanocrystalline Pd thin films Type A1 Journal article
  Year 2015 Publication International journal of hydrogen energy Abbreviated Journal Int J Hydrogen Energ  
  Volume 40 Issue 40 Pages 7335-7347  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)  
  Abstract (up) While the microstructure of a metal is well-known to affect its equilibrium hydrogen uptake and therefore the hydriding thermodynamics, microstructural effects on the hydriding kinetics are much less documented. Moreover, for thin film systems, such microstructural effects are difficult to separate from the internal stress effect, since most defects generate internal stresses. Such a decoupling has been achieved in this paper for nanocrystalline Pd thin film model systems through the use of a high-resolution, in-situ curvature measurement set-up during Pd deposition, annealing and hydriding. This set-up allowed producing Pd thin films with similar internal stress levels but significantly different microstructures. This was evidenced from detailed defect statistics obtained by transmission electron microscopy, which showed that the densities of grain boundaries, dislocations and twin boundaries have all been lowered by annealing. The same set-up was then used to study the hydriding equilibrium and kinetic behaviour of the resulting films at room temperature. A full quantitative analysis of their hydriding cycles showed that the rate constants of both the adsorption- and absorption-limited kinetic regimes were strongly affected by microstructure. Defect engineering was thereby shown to increase the rate constants for hydrogen adsorption and absorption in Pd by a factor 40 and 30, respectively. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Oxford Editor  
  Language Wos 000355884300012 Publication Date 2015-05-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0360-3199; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.582 Times cited 13 Open Access  
  Notes Iap 7/21 Approved Most recent IF: 3.582; 2015 IF: 3.313  
  Call Number c:irua:126429 Serial 838  
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Author da Costa, D.R.; Zarenia, M.; Chaves, A.; Farias, G.A.; Peeters, F.M. url  doi
openurl 
  Title Energy levels of bilayer graphene quantum dots Type A1 Journal article
  Year 2015 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 92 Issue 92 Pages 115437  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) Within a tight binding approach we investigate the energy levels of hexagonal and triangular bilayer graphene (BLG) quantum dots (QDs) with zigzag and armchair edges. We study AA- and AB-(Bernal) stacked BLG QDs and obtain the energy levels in both the absence and the presence of a perpendicular electric field (i.e., biased BLG QDs). Our results show that the size dependence of the energy levels is different from that of monolayer graphene QDs. The energy spectrum of AB-stacked BLG QDs with zigzag edges exhibits edge states which spread out into the opened energy gap in the presence of a perpendicular electric field. We found that the behavior of these edges states is different for the hexagonal and triangular geometries. In the case of AA-stacked BLG QDs, the electron and hole energy levels cross each other in both cases of armchair and zigzag edges as the dot size or the applied bias increases.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000361663700003 Publication Date 2015-09-24  
  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 financially supported by CNPq, under contract NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES Foundation under the process number BEX 7178/13-1, the Flemish Science Foundation (FWO-Vl), the Bilateral programme between CNPq and FWO-Vl, and the Brazilian Program Science Without Borders (CsF). ; Approved Most recent IF: 3.836; 2015 IF: 3.736  
  Call Number UA @ lucian @ c:irua:128726 Serial 4173  
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Author Caretti, I.; Keulemans, M.; Verbruggen, S.W.; Lenaerts, S.; Van Doorslaer, S. pdf  url
doi  openurl
  Title Light-induced processes in plasmonic Gold/TiO2 photocatalysts studied by electron paramagnetic resonance Type A1 Journal article
  Year 2015 Publication Topics in catalysis Abbreviated Journal Top Catal  
  Volume 58 Issue 12 Pages 776-782  
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)  
  Abstract (up) X-band and W-band continuous-wave (CW) electron paramagnetic resonance (EPR) was used to study in situ light-induced (LI) mechanisms in commercial P90 titania (90 % anatase/10 % rutile) compared to plasmon-enhanced Au-P90 photocatalyst. These materials were excited using UV and 532 nm visible light to generate different excitation states and distinguish pure charge separation from plasmon-assisted resonance processes. Up to nine different photoinduced species of trapped electrons and holes were identified. LI CW EPR of P90 is presented for the first time, showing a UV excitation response similar to the well-known mixed-phase P25 titania. It is shown that incorporation of Au nanoparticles in Au-P90 and formation of a Schottky junction affects the charge separation state of the catalyst under UV light. Moreover, Au impregnation activated P90 through plasmon hot electron injection under visible light excitation (plasmonic sensitization effect). In general, EPR proved to be crucial to determine the different photoexciation paths and reactions that regulate plasmonic photocatalysis.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000360011200008 Publication Date 2015-08-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1022-5528 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.486 Times cited 22 Open Access  
  Notes ; IC and SVD acknowledge the Research Foundation-Flanders (FWO) for financial support (Grant G.0687.13). SV thanks FWO for financial support through a postdoctoral fellowship and MK acknowledges the agency for Innovation by Science and Technology in Flanders (IWT) for financial support (Ph.D. Grant). ; Approved Most recent IF: 2.486; 2015 IF: 2.365  
  Call Number UA @ admin @ c:irua:127413 Serial 5968  
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Author Nicholls, D.; Li, R.R.; Ware, B.; Pansegrau, C.; Çakir, D.; Hoffmann, M.R.; Oncel, N. doi  openurl
  Title Scanning tunneling microscopy and density functional theory study on zinc(II)-phthalocyanine tetrasulfonic acid on bilayer epitaxial graphene on silicon carbide(0001) Type A1 Journal article
  Year 2015 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 119 Issue 119 Pages 9845-9850  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract (up) Zinc(II)-phthalocyanine tetrasulfonic acid (Zn-PcS) molecules physisorbed on bilayer epitaxial graphene on silicon carbide (SiC(0001)) were studied by using scanning tunneling microscopy/spectroscopy (STM/STS) and density functional theory (DFT). Two different methods were used to deposit Zn-PcS molecules and regardless of the method being used, the surface coverage stayed very low indicating the weakness of surface-molecule interaction. STS measurements revealed that derivative of tunneling current with respect to voltage (dI/dV) measured on Zn-PcS molecules did not exhibit the characteristic dip observed on dI/dV curves of pristine bilayer epitaxial graphene. DFT calculations show that the energy of the lowest unoccupied molecular orbital (LUMO) of the Zn-PcS molecule is below the Dirac point of graphene which enhances local density of states (LDOS). We attribute the disappearance of the dip in the dI/dV curves measured on the Zn-PcS/bilayer system to the LUMO of Zn-PcS. Charge density calculations along Zn-PcS/graphene interface reveal that there is a small charge transfer from graphene to the molecule. Calculated adsorption energy (3.13 eV) of the molecule is notably low and is consistent with the observed low surface coverage at room temperature.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos 000354339000020 Publication Date 2015-04-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447;1932-7455; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited 3 Open Access  
  Notes ; We gratefully acknowledge the NSF (Grant Nos.: DMR-1306101, EPS-814442, and EPS-1354366) for financial support. ; Approved Most recent IF: 4.536; 2015 IF: 4.772  
  Call Number c:irua:126370 Serial 2947  
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