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Author Bal, K.M.
  Title Nucleation rates from small scale atomistic simulations and transition state theory Type A1 Journal article
  Year 2021 Publication Journal Of Chemical Physics Abbreviated Journal J Chem Phys
  Volume 155 Issue 14 Pages 144111
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract The evaluation of nucleation rates from molecular dynamics trajectories is hampered by the slow nucleation time scale and impact of finite size effects. Here, we show that accurate nucleation rates can be obtained in a very general fashion relying only on the free energy barrier, transition state theory, and a simple dynamical correction for diffusive recrossing. In this setup, the time scale problem is overcome by using enhanced sampling methods, in casu metadynamics, whereas the impact of finite size effects can be naturally circumvented by reconstructing the free energy surface from an appropriate ensemble. Approximations from classical nucleation theory are avoided. We demonstrate the accuracy of the approach by calculating macroscopic rates of droplet nucleation from argon vapor, spanning 16 orders of magnitude and in excellent agreement with literature results, all from simulations of very small (512 atom) systems.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000755502100008 Publication Date 2021-09-30
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-9606 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.965 Times cited Open Access OpenAccess
  Notes Approved Most recent IF: 2.965
  Call Number UA @ admin @ c:irua:184937 Serial 8320
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Author Verheyen, E.; Jo, C.; Kurttepeli, M.; Vanbutsele, G.; Gobechiya, E.; Korányi, T.I.; Bals, S.; Van Tendeloo, G.; Ryoo, R.; Kirschhock, C.E.A.; Martens, J.A.;
  Title Molecular shape-selectivity of MFI zeolite nanosheets in n-decane isomerization and hydrocracking Type A1 Journal article
  Year 2013 Publication Journal of catalysis Abbreviated Journal J Catal
  Volume 300 Issue Pages 70-80
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract MFI zeolite nanosheets with thickness of 2 and 8 nm were synthesized, transformed into bifunctional catalysts by loading with platinum and tested in n-decane isomerization and hydrocracking. Detailed analysis of skeletal isomers and hydrocracked products revealed that the MFI nanosheets display transition-state shape-selectivity similar to bulk MFI zeolite crystals. The suppressed formation of bulky skeletal isomers and C5 cracking products are observed both in the nanosheets and the bulk crystals grown in three dimensions. This is typical for restricted transition-state shape-selectivity, characteristic for the MFI type pores. It is a first clear example of transition-state shape-selectivity inside a zeolitic nanosheet. Owing to the short diffusion path across the sheets, expression of diffusion-based discrimination of reaction products in the MFI nanosheets was limited. The 2-methylnonane formation among monobranched C10 isomers and 2,7-dimethyloctane among dibranched C10 isomers, which in MFI zeolite are favored by product diffusion, was much less favored on the nanosheets compared to the reference bulk ZSM-5 material.
  Address
  Corporate Author Thesis
  Publisher Place of Publication San Diego, Calif. Editor
  Language Wos 000317558000009 Publication Date 2013-02-07
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-9517; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.844 Times cited 121 Open Access
  Notes Methusalem; IAP; Countatoms Approved Most recent IF: 6.844; 2013 IF: 6.073
  Call Number UA @ lucian @ c:irua:106186 Serial 2181
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Author Dams, M.; Drijkoningen, L.; Pauwels, B.; Van Tendeloo, G.; de Vos, D.E.; Jacobs, P.A.
  Title Pd-zeolites as heterogeneous catalysts in heck chemistry Type A1 Journal article
  Year 2002 Publication Journal of catalysis Abbreviated Journal J Catal
  Volume 209 Issue 1 Pages 225-236
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000176501100027 Publication Date 2002-10-06
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-9517; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.844 Times cited 157 Open Access
  Notes Approved Most recent IF: 6.844; 2002 IF: 3.118
  Call Number UA @ lucian @ c:irua:54844 Serial 2567
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Author Philippaerts, A.; Paulussen, S.; Turner, S.; Lebedev, O.I.; Van Tendeloo, G.; Poelman, H.; Bulut, M.; de Clippel, F.; Smeets, P.; Sels, B.; Jacobs, P.
  Title Selectivity in sorption and hydrogenation of methyl oleate and elaidate on MFI zeolites Type A1 Journal article
  Year 2010 Publication Journal of catalysis Abbreviated Journal J Catal
  Volume 270 Issue 1 Pages 172-184
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Different zeolites were tested for selective removal of methyl elaidate (trans isomer) from an equimolar mixture with methyl oleate (cis isomer). Sorption experiments of the geometric isomers show that only ZSM-5 samples with reduced Al content in the framework are able to discriminate among the bent cis and the linear trans fatty acid methyl esters. Hydrogenation experiments of equimolar methyl oleate and elaidate mixtures at low temperature (65 °C) and high hydrogen pressure (6.0 MPa), using Pt catalysts, confirm this result. Only with a Pt/NaZSM-5 catalyst outspoken selectivity for the hydrogenation of the trans isomer is obtained. In order to prepare a selective Pt/ZSM-5 catalyst, the influence of Pt addition (impregnation, ion-exchange and competitive ion-exchange) and Pt activation (different calcination and reduction temperatures) on the Pt-distribution and Pt particle size was investigated using SEM, bright-field and HR TEM, EDX, electron tomography, CO-chemisorption, XPS, XRD, and UVvis measurements. The best result in terms of hydrogenation activity and selectivity is obtained with a Pt/ZSM-5 catalyst, which is prepared via competitive ion-exchange, followed by slow calcination up to 350 °C under high O2 flow and a reduction up to 500 °C under H2. This preparation method leads to a Pt/ZSM-5 catalyst with the best Pt distribution and the smallest Pt clusters occluded in the zeolite structure. Finally, the influence of zeolite crystal size, morphology, and elemental composition of ZSM-5 on hydrogenation activity and selectivity was investigated in detail.
  Address
  Corporate Author Thesis
  Publisher Place of Publication San Diego, Calif. Editor
  Language Wos 000275966100021 Publication Date 2010-01-28
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-9517; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.844 Times cited 24 Open Access
  Notes FWO; IAP-IV; Methusalem Approved Most recent IF: 6.844; 2010 IF: 5.415
  Call Number UA @ lucian @ c:irua:82435 Serial 2970
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Author Leus, K.; Liu, Y.-Y.; Meledina, M.; Turner, S.; Van Tendeloo, G.; van der Voort, P.
  Title A MoVI grafted metal organic framework : synthesis, characterization and catalytic investigations Type A1 Journal article
  Year 2014 Publication Journal of catalysis Abbreviated Journal J Catal
  Volume 316 Issue Pages 201-209
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract We present the post-modification of a gallium based Metal Organic Framework, COMOC-4, with a Mo-complex. The resulting Mo@COMOC-4 was characterized by means of N2 sorption, XRPD, DRIFT, TGA, XRF, XPS and TEM analysis. The results demonstrate that even at high Mo-complex loadings on the framework, no aggregation or any Mo or Mo oxide species are formed. Moreover, the Mo@COMOC-4 was evaluated as a catalyst in the epoxidation of cyclohexene, cyclooctene and cyclododecene employing TBHP in decane as oxidant. The post-modified COMOC-4 exhibits a very high selectivity toward the epoxide (up to 100%). Regenerability and stability tests have been carried out demonstrating that the catalyst can be recycled without leaching of Mo or loss of crystallinity.
  Address
  Corporate Author Thesis
  Publisher Place of Publication San Diego, Calif. Editor
  Language Wos 000340853800020 Publication Date 2014-06-19
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-9517; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.844 Times cited 36 Open Access
  Notes European Research Council under the Seventh Framework Program (FP7); ; ERC Grant No. 246791 – COUNTATOMS; Hercules; FWO Approved Most recent IF: 6.844; 2014 IF: 6.921
  Call Number UA @ lucian @ c:irua:117416 Serial 3546
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Author Mahr, C.; Kundu, P.; Lackmann, A.; Zanaga, D.; Thiel, K.; Schowalter, M.; Schwan, M.; Bals, S.; Wittstock, A.; Rosenauer, A.
  Title Quantitative determination of residual silver distribution in nanoporous gold and its influence on structure and catalytic performance Type A1 Journal article
  Year 2017 Publication Journal of catalysis Abbreviated Journal J Catal
  Volume 352 Issue 352 Pages 52-58
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Large efforts have been made trying to understand the origin of the high catalytic activity of dealloyed nanoporous gold as a green catalyst for the selective promotion of chemical reactions at low temperatures. Residual silver, left in the sample after dealloying of a gold-silver alloy, has been shown to have a strong influence on the activity of the catalyst. But the question of how the silver is distributed within the porous structure has not finally been answered yet. We show by quantitative energy dispersive X-ray tomography measurements that silver forms clusters that are distributed irregularly, both on the surface and inside the ligaments building up the porous structure. Furthermore, we find that the role of the residual silver is ambiguous. Whereas CO oxidation is supported by more residual silver, methanol oxidation to methyl formate is hindered. Structural characterisation reveals larger ligaments and pores for decreasing residual silver concentration.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000408299600006 Publication Date 2017-05-29
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-9517 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.844 Times cited 42 Open Access OpenAccess
  Notes This work was supported by the Deutsche Forschungsgemeinschaft (DFG) under contracts no. RO2057/12-1 (SP 6) and WI4497/1-1 (SP 2) within the research unit FOR2213 (www.nagocat. de) and the European Research Council (ERC Starting Grant No. 335078-COLOURATOMS). (ROMEO:green; preprint:; postprint:can ; pdfversion:cannot); ecas_sara Approved Most recent IF: 6.844
  Call Number EMAT @ emat @c:irua:144434UA @ admin @ c:irua:144434 Serial 4623
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Author Keulemans, M.; Verbruggen, S.W.; Hauchecorne, B.; Martens, J.A.; Lenaerts, S.
  Title Activity versus selectivity in photocatalysis : morphological or electronic properties tipping the scale Type A1 Journal article
  Year 2016 Publication Journal of catalysis Abbreviated Journal J Catal
  Volume 344 Issue Pages 221-228
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
  Abstract In this paper a structure-activity and structure-selectivity relation is established for three commercial TiO2 sources (P25, P90, and PC500). Morphological and electronic parameters of the photocatalysts are determined using widely applicable and inexpensive characterization procedures. More specifically, the electronic properties are rigorously characterized using an electron titration method yielding quantitative information on the amount of defect sites present in the catalyst. Surface photovoltage measurements on the other hand provide complementary information on the charge carrier recombination process. As model reaction, the degradation of a solid layer of stearic acid is studied using an in situ FTIR reaction cell that enables to investigate the catalyst surface and possible formation of reaction intermediates while the reactions are ongoing. We show that the order of photocatalytic conversion is PC500 > P90 > P25, matching the order of favorable morphological properties. In terms of selectivity to CO2 formation (complete mineralization), however, this trend is reversed: P25 > P90 > PC500, now matching the order of advantageous electronic properties, i.e. low charge carrier recombination and high charge carrier generation. With this we intend to provide new mechanistic insights using a wide variety of physical, (wet) chemical and operando analysis methods that aid the development of performant (self-cleaning) photocatalytic materials.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000390182800022 Publication Date 2016-10-15
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-9517 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 6.844 Times cited 10 Open Access
  Notes ; M.K. acknowledges Flemish Agency for Innovation & Entrepreneurship for the doctoral scholarship. S.W.V. acknowledges the Fonds Wetenschappelijk Onderzoek (FWO) for a post-doctoral fellowship. J.A.M. acknowledges the Flemish government for long-term structural funding (Methusalem). ; Approved Most recent IF: 6.844
  Call Number UA @ admin @ c:irua:136339 Serial 5926
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Author van Holsbeke, C.; de Backer, J.; Vos, W.; Verdonck, P.; van Ransbeeck, P.; Claessens, T.; Braem, M.; Vanderveken, O.; de Backer, W.
  Title Anatomical and functional changes in the upper airways of sleep apnea patients due to mandibular repositioning: a large scale study Type A1 Journal article
  Year 2011 Publication Journal of biomechanics Abbreviated Journal J Biomech
  Volume 44 Issue 3 Pages 442-449
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Vision lab; Laboratory Experimental Medicine and Pediatrics (LEMP); Translational Neurosciences (TNW)
  Abstract The obstructive sleep apnea-hypopnea syndrome (OSAHS) is a sleep related breathing disorder. A popular treatment is the use of a mandibular repositioning appliance (MRA) which advances the mandibula during the sleep and decreases the collapsibility of the upper airway. The success rate of such a device is, however, limited and very variable within a population of patients. Previous studies using computational fluid dynamics have shown that there is a decrease in upper airway resistance in patients who improve clinically due to an MRA. In this article, correlations between patient-specific anatomical and functional parameters are studied to examine how MRA induced biomechanical changes will have an impact on the upper airway resistance. Low-dose computed tomography (CT) scans are made from 143 patients suffering from OSAHS. A baseline scan and a scan after mandibular repositioning (MR) are performed in order to study variations in parameters. It is found that MR using a simulation bite is able to induce resistance changes by changing the pharyngeal lumen. The change in minimal cross-sectional area is the best parameter to predict the change in upper airway resistance. Looking at baseline values, the ideal patients for MR induced resistance decrease seem to be women with short airways, high initial resistance and no baseline occlusion.
  Address
  Corporate Author Thesis
  Publisher Place of Publication New York, N.Y. Editor
  Language Wos 000287551000014 Publication Date 2010-10-23
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-9290; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.664 Times cited 23 Open Access
  Notes ; ; Approved Most recent IF: 2.664; 2011 IF: 2.434
  Call Number UA @ lucian @ c:irua:85305 Serial 112
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Author de Backer, J.W.; Vos, W.G.; Devolder, A.; Verhulst, S.L.; Germonpré, P.; Wuyts, F.L.; Parizel, P.M.; de Backer, W.
  Title Computational fluid dynamics can detect changes in airway resistance in asthmatics after acute bronchodilation Type A1 Journal article
  Year 2008 Publication Journal of biomechanics Abbreviated Journal J Biomech
  Volume 41 Issue 1 Pages 106-113
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication New York, N.Y. Editor
  Language Wos 000253062100014 Publication Date 2007-08-15
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-9290; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.664 Times cited 53 Open Access
  Notes Approved Most recent IF: 2.664; 2008 IF: 2.784
  Call Number UA @ lucian @ c:irua:64859 Serial 456
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Author de Backer, J.W.; Vanderveken, O.M.; Vos, W.G.; Devolder, A.; Verhulst, S.L.; Verbraecken, J.A.; Parizel, P.M.; Braem, M.J.; van de Heyning, P.H.; de Backer, W.A.
  Title Functional imaging using computational fluid dynamics to predict treatment success of mandibular advancement devices in sleep-disordered breathing Type A1 Journal article
  Year 2007 Publication Journal of biomechanics Abbreviated Journal J Biomech
  Volume 40 Issue 16 Pages 3708-3714
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP); Translational Neurosciences (TNW)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication New York, N.Y. Editor
  Language Wos 000251845100020 Publication Date 2007-08-01
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-9290; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.664 Times cited 66 Open Access
  Notes Approved Most recent IF: 2.664; 2007 IF: 2.897
  Call Number UA @ lucian @ c:irua:64860 Serial 1299
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Author Trashin, S.; De Jong, M.; Luyckx, E.; Dewilde, S.; De Wael, K.
  Title Electrochemical evidence for neuroglobin activity on NO at physiological concentrations Type A1 Journal article
  Year 2016 Publication Journal of biological chemistry Abbreviated Journal J Biol Chem
  Volume 291 Issue 36 Pages 18959-18966
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract The true function of neuroglobin (Ngb) and, particularly, human Ngb (NGB) has been under debate since its discovery 15 years ago. It has been expected to play a role in oxygen binding/supply, but a variety of other functions have been put forward, including NO dioxygenase activity. However, in vitro studies that could unravel these potential roles have been hampered by the lack of an Ngb-specific reductase. In this work, we used electrochemical measurements to investigate the role of an intermittent internal disulfide bridge in determining NO oxidation kinetics at physiological NO concentrations. The use of a polarized electrode to efficiently interconvert the ferric (Fe3+) and ferrous (Fe2+) forms of an immobilized NGB showed that the disulfide bridge both defines the kinetics of NO dioxygenase activity and regulates appearance of the free ferrous deoxy-NGB, which is the redox active form of the protein in contrast to oxy-NGB. Our studies further identified a role for the distal histidine, interacting with the hexacoordinated iron atom of the heme, in oxidation kinetics. These findings may be relevant in vivo, for example in blocking apoptosis by reduction of ferric cytochrome c, and gentle tuning of NO concentration in the tissues.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000383242300031 Publication Date 2016-07-12
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-9258; 1083-351x ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 4.125 Times cited 11 Open Access
  Notes ; This work was supported by Fonds Wetenschappelijk Onderzoek (FWO) Grant G.0687.13 and Universiteit Antwerpen GOA BOF 28312. The authors declare that they have no conflicts of interest with the contents of this article. ; Approved Most recent IF: 4.125
  Call Number UA @ admin @ c:irua:134340 Serial 5590
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Author Berdiyorov, G.; Harrabi, K.; Mehmood, U.; Peeters, F.M.; Tabet, N.; Zhang, J.; Hussein, I.A.; McLachlan, M.A.
  Title Derivatization and diffusive motion of molecular fullerenes : ab initio and atomistic simulations Type A1 Journal article
  Year 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 118 Issue 118 Pages 025101
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Using first principles density functional theory in combination with the nonequilibrium Green's function formalism, we study the effect of derivatization on the electronic and transport properties of C-60 fullerene. As a typical example, we consider [6,6]-phenyl-C-61-butyric acid methyl ester (PCBM), which forms one of the most efficient organic photovoltaic materials in combination with electron donating polymers. Extra peaks are observed in the density of states (DOS) due to the formation of new electronic states localized at/near the attached molecule. Despite such peculiar behavior in the DOS of an isolated molecule, derivatization does not have a pronounced effect on the electronic transport properties of the fullerene molecular junctions. Both C-60 and PCBM show the same response to finite voltage biasing with new features in the transmission spectrum due to voltage induced delocalization of some electronic states. We also study the diffusive motion of molecular fullerenes in ethanol solvent and inside poly(3-hexylthiophene) lamella using reactive molecular dynamics simulations. We found that the mobility of the fullerene reduces considerably due to derivatization; the diffusion coefficient of C-60 is an order of magnitude larger than the one for PCBM. (c) 2015 AIP Publishing LLC.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000357961000036 Publication Date 2015-07-10
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 2 Open Access
  Notes ; K.H., U.M. and I.A.H. would like to thank the National Science, Technology and Innovation Program of KACST for funding this research under Project No. 12-ENE2379-04. They also acknowledge support from KFUPM and Research Institute. ; Approved Most recent IF: 2.068; 2015 IF: 2.183
  Call Number c:irua:127098 Serial 652
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Author Milovanović, S.P.; Moldovan, D.; Peeters, F.M.
  Title Veselago lensing in graphene with a p-n junction: Classical versus quantum effects Type A1 Journal article
  Year 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 118 Issue 118 Pages 154308
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The feasibility of Veselago lensing in graphene with a p-n junction is investigated numerically for realistic injection leads. Two different set-ups with two narrow leads are considered with absorbing or reflecting side edges. This allows us to separately determine the influence of scattering on electron focusing for the edges and the p-n interface. Both semiclassical and tight-binding simulations show a distinctive peak in the transmission probability that is attributed to the Veselago lensing effect. We investigate the robustness of this peak on the width of the injector, the position of the p-n interface, and different gate potential profiles. Furthermore, the influence of scattering by both short- and long-range impurities is considered.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000363535800022 Publication Date 2015-10-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 19 Open Access
  Notes This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN, and the Methusalem Foundation of the Flemish government. Approved Most recent IF: 2.068; 2015 IF: 2.183
  Call Number c:irua:129452 Serial 3969
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Author Smets, Q.; Verreck, D.; Verhulst, A.S.; Rooyackers, R.; Merckling, C.; Van De Put, M.; Simoen, E.; Vandervorst, W.; Collaert, N.; Thean, V.Y.; Sorée, B.; Groeseneken, G.; Heyns, M.M.;
  Title InGaAs tunnel diodes for the calibration of semi-classical and quantum mechanical band-to-band tunneling models Type A1 Journal article
  Year 2014 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 115 Issue 18 Pages 184503-184509
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Promising predictions are made for III-V tunnel-field-effect transistor (FET), but there is still uncertainty on the parameters used in the band-to-band tunneling models. Therefore, two simulators are calibrated in this paper; the first one uses a semi-classical tunneling model based on Kane's formalism, and the second one is a quantum mechanical simulator implemented with an envelope function formalism. The calibration is done for In0.53Ga0.47As using several p+/intrinsic/n+ diodes with different intrinsic region thicknesses. The dopant profile is determined by SIMS and capacitance-voltage measurements. Error bars are used based on statistical and systematic uncertainties in the measurement techniques. The obtained parameters are in close agreement with theoretically predicted values and validate the semi-classical and quantum mechanical models. Finally, the models are applied to predict the input characteristics of In0.53Ga0.47As n- and p-lineTFET, with the n-lineTFET showing competitive performance compared to MOSFET.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000336919400048 Publication Date 2014-05-14
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 34 Open Access
  Notes ; Quentin Smets and Devin Verreck gratefully acknowledge the support of a Ph. D. stipend from IWT-Vlaanderen. This work was supported by imec's industrial affiliation program. The authors thank Kim Baumans, Johan Feyaerts, Johan De Cooman, Alireza Alian, and Jos Moonens for their support in process development; Bastien Douhard and Joris Delmotte for SIMS characterization; Alain Moussa for AFM characterization; Joris Van Laer and Tom Daenen for their support in electrical characterization; Kuo-Hsing Kao, Mehbuba Tanzid, and Ali Pourghaderi for their support in modeling. ; Approved Most recent IF: 2.068; 2014 IF: 2.183
  Call Number UA @ lucian @ c:irua:118009 Serial 1667
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Author Milovanović, S.P.; Masir, M.R.; Peeters, F.M.
  Title Magnetic electron focusing and tuning of the electron current with a pn-junction Type A1 Journal article
  Year 2014 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 115 Issue 4 Pages 043719-6
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Transverse magnetic focusing properties of graphene using a ballistic four terminal structure are investigated. The electric response is obtained using the semiclassical billiard model. The transmission exhibits pronounced peaks as a consequence of skipping orbits at the edge of the structure. When we add a pn-junction between the two probes, snake states along the pn-interface appear. Injected electrons are guided by the pn-interface to one of the leads depending on the value of the applied magnetic field. Oscillations in the resistance are found depending on the amount of particles that end up in each lead.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000331210800066 Publication Date 2014-01-30
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 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 within the project CONGRAN, and the Methusalem Foundation of the Flemish government. Approved Most recent IF: 2.068; 2014 IF: 2.183
  Call Number UA @ lucian @ c:irua:115801 Serial 1866
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Author Sen, H.S.; Sahin, H.; Peeters, F.M.; Durgun, E.
  Title Monolayers of MoS2 as an oxidation protective nanocoating material Type A1 Journal article
  Year 2014 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 116 Issue 8 Pages 083508
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract First-principle calculations are employed to investigate the interaction of oxygen with ideal and defective MoS2 monolayers. Our calculations show that while oxygen atoms are strongly bound on top of sulfur atoms, the oxygen molecule only weakly interacts with the surface. The penetration of oxygen atoms and molecules through a defect-free MoS2 monolayer is prevented by a very high diffusion barrier indicating that MoS2 can serve as a protective layer for oxidation. The analysis is extended to WS2 and similar coating characteristics are obtained. Our calculations indicate that ideal and continuous MoS2 and WS2 monolayers can improve the oxidation and corrosion-resistance of the covered surface and can be considered as an efficient nanocoating material. (C) 2014 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000342821600017 Publication Date 2014-08-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 52 Open Access
  Notes ; This work was supported by the bilateral project between TUBITAK (through Grant No. 113T050) and Flemish Science Foundation (FWO-Vl). The calculations were performed at TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). E.D. acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. H.S. is supported by an FWO Pegasus-long Marie Curie Fellowship. ; Approved Most recent IF: 2.068; 2014 IF: 2.183
  Call Number UA @ lucian @ c:irua:121101 Serial 2194
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Author Li, L.L.; Xu, W.; Peeters, F.M.
  Title Optical conductivity of topological insulator thin films Type A1 Journal article
  Year 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 117 Issue 117 Pages 175305
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We present a detailed theoretical study on the optoelectronic properties of topological insulator thin film (TITFs). The k . p approach is employed to calculate the energy spectra and wave functions for both the bulk and surface states in the TITF. With these obtained results, the optical conductivities induced by different electronic transitions among the bulk and surface states are evaluated using the energy-balance equation derived from the Boltzmann equation. We find that for Bi2Se3-based TITFs, three characteristic regimes for the optical absorption can be observed. (i) In the low radiation frequency regime (photon energy (h) over bar omega < 200 meV), the free-carrier absorption takes place due to intraband electronic transitions. An optical absorption window can be observed. (ii) In the intermediate radiation frequency regime (200 < (h) over bar omega < 300 meV), the optical absorption is induced mainly by interband electronic transitions from surface states in the valance band to surface states in the conduction band and an universal value sigma(0) = e(2) / (8<(h)over bar>) for the optical conductivity can be obtained. (iii) In the high radiation frequency regime ((h) over bar omega > 300 meV), the optical absorption can be achieved via interband electronic transitions from bulk and surface states in the valance band to bulk and surface states in the conduction band. A strong absorption peak can be observed. These interesting findings indicate that optical measurements can be applied to identify the energy regimes of bulk and surface states in the TITF. (C) 2015 AIP Publishing LLC.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000354984100615 Publication Date 2015-05-06
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 9 Open Access
  Notes ; This work was supported by the National Natural Science Foundation of China (Grant No. 11304316), Ministry of Science and Technology of China (Grant No. 2011YQ130018), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. ; Approved Most recent IF: 2.068; 2015 IF: 2.183
  Call Number c:irua:126412 Serial 2473
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Author Verreck, D.; Van de Put, M.; Sorée, B.; Verhulst, A.S.; Magnus, W.; Vandenberghe, W.G.; Collaert, N.; Thean, A.; Groeseneken, G.
  Title Quantum mechanical solver for confined heterostructure tunnel field-effect transistors Type A1 Journal article
  Year 2014 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 115 Issue 5 Pages 053706-53708
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Heterostructure tunnel field-effect transistors (HTFET) are promising candidates for low-power applications in future technology nodes, as they are predicted to offer high on-currents, combined with a sub-60 mV/dec subthreshold swing. However, the effects of important quantum mechanical phenomena like size confinement at the heterojunction are not well understood, due to the theoretical and computational difficulties in modeling realistic heterostructures. We therefore present a ballistic quantum transport formalism, combining a novel envelope function approach for semiconductor heterostructures with the multiband quantum transmitting boundary method, which we extend to 2D potentials. We demonstrate an implementation of a 2-band version of the formalism and apply it to study confinement in realistic heterostructure diodes and p-n-i-n HTFETs. For the diodes, both transmission probabilities and current densities are found to decrease with stronger confinement. For the p-n-i-n HTFETs, the improved gate control is found to counteract the deterioration due to confinement. (C) 2014 AIP Publishing LLC.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000331645900040 Publication Date 2014-02-05
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 15 Open Access
  Notes ; D. Verreck acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). This work was supported by imec's Industrial Affiliation Program. ; Approved Most recent IF: 2.068; 2014 IF: 2.183
  Call Number UA @ lucian @ c:irua:115825 Serial 2780
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Author Kao, K.-H.; Verhulst, A.S.; Van de Put, M.; Vandenberghe, W.G.; Sorée, B.; Magnus, W.; De Meyer, K.
  Title Tensile strained Ge tunnel field-effect transistors: k\cdot p material modeling and numerical device simulation Type A1 Journal article
  Year 2014 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 115 Issue 4 Pages 044505-44508
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Group IV based tunnel field-effect transistors generally show lower on-current than III-V based devices because of the weaker phonon-assisted tunneling transitions in the group IV indirect bandgap materials. Direct tunneling in Ge, however, can be enhanced by strain engineering. In this work, we use a 30-band k.p method to calculate the band structure of biaxial tensile strained Ge and then extract the bandgaps and effective masses at Gamma and L symmetry points in k-space, from which the parameters for the direct and indirect band-to-band tunneling (BTBT) models are determined. While transitions from the heavy and light hole valence bands to the conduction band edge at the L point are always bridged by phonon scattering, we highlight a new finding that only the light-holelike valence band is strongly coupling to the conduction band at the Gamma point even in the presence of strain based on the 30-band k.p analysis. By utilizing a Technology Computer Aided Design simulator equipped with the calculated band-to-band tunneling BTBT models, the electrical characteristics of tensile strained Ge point and line tunneling devices are self-consistently computed considering multiple dynamic nonlocal tunnel paths. The influence of field-induced quantum confinement on the tunneling onset is included. Our simulation predicts that an on-current up to 160 (260) mu A/mu m can be achieved along with on/off ratio > 10(6) for V-DD = 0.5V by the n-type (p-type) line tunneling device made of 2.5% biaxial tensile strained Ge. (C) 2014 AIP Publishing LLC.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000331210800113 Publication Date 2014-01-26
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 26 Open Access
  Notes ; Authors would like to thank Dr. Mohammad Ali Pourghaderi for useful discussions on the nonparabolicity. Authors would also like to thank Professor Eddy Simoen and Dr. Yosuke Shimura for useful discussions about the validity of modeled bandgaps and effective masses. This work was also supported by IMEC's Industrial Affiliation Program. ; Approved Most recent IF: 2.068; 2014 IF: 2.183
  Call Number UA @ lucian @ c:irua:115800 Serial 3505
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Author Zhao, C.X.; Xu, W.; Li, L.L.; Zhang, C.; Peeters, F.M.
  Title Terahertz plasmon-polariton modes in graphene driven by electric field inside a Fabry-Perot cavity Type A1 Journal article
  Year 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 117 Issue 117 Pages 223104
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We present a theoretical study on plasmon-polariton modes in graphene placed inside an optical cavity and driven by a source-to-drain electric field. The electron velocity and electron temperature are determined by solving self-consistently the momentum-and energy-balance equations in which electron interactions with impurities, acoustic-, and optic-phonons are included. Based on many-body self-consistent field theory, we develop a tractable approach to study plasmon-polariton in an electron gas system. We find that when graphene is placed inside a Fabry-Perot cavity, two branches of the plasmon-polariton modes can be observed and these modes are very much optic-or plasmon-like. The frequencies of these modes depend markedly on driving electric field especially at higher resonant frequency regime. Moreover, the plasmon-polariton frequency in graphene is in terahertz (THz) bandwidth and can be tuned by changing the cavity length, gate voltage, and driving electric field. This work is pertinent to the application of graphene-based structures as tunable THz plasmonic devices. (C) 2015 AIP Publishing LLC.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000356176100004 Publication Date 2015-06-10
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 13 Open Access
  Notes ; This work was supported by the Ministry of Science and Technology of China (Grant No. 2011YQ130018), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. F.M.P. was a specially appointed Professor for foreign expert at the Chinese Academy of Sciences. ; Approved Most recent IF: 2.068; 2015 IF: 2.183
  Call Number c:irua:127076 Serial 3507
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Author Berdiyorov, G.R.; Bahlouli, H.; Peeters, F.M.
  Title Theoretical study of electronic transport properties of a graphene-silicene bilayer Type A1 Journal article
  Year 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 117 Issue 117 Pages 225101
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Electronic transport properties of a graphene-silicene bilayer system are studied using density-functional theory in combination with the nonequilibrium Green's function formalism. Depending on the energy of the electrons, the transmission can be larger in this system as compared to the sum of the transmissions of separated graphene and silicene monolayers. This effect is related to the increased electron density of states in the bilayer sample. At some energies, the electronic states become localized in one of the layers, resulting in the suppression of the electron transmission. The effect of an applied voltage on the transmission becomes more pronounced in the layered sample as compared to graphene due to the larger variation of the electrostatic potential profile. Our findings will be useful when creating hybrid nanoscale devices where enhanced transport properties will be desirable. (C) 2015 AIP Publishing LLC.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000356176100040 Publication Date 2015-06-10
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 10 Open Access
  Notes ; H. B. and F. M. P. acknowledge support from King Fahd University of Petroleum and Minerals, Saudi Arabia, under the RG1329-1 and RG1329-2 DSR Projects. ; Approved Most recent IF: 2.068; 2015 IF: 2.183
  Call Number c:irua:127075 Serial 3611
Permanent link to this record
 

 
Author Chu, D.P.; Peeters, F.M.; Kolodinski, S.; Roca, E.
  Title Theoretical investigation of CoSi2/Si1-xGex detectors: influence of a Si tunneling barrier on the electro-optical characteristics Type A1 Journal article
  Year 1996 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 79 Issue Pages 1151-1156
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos A1996TQ77500084 Publication Date 0000-00-00
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.183 Times cited 3 Open Access
  Notes Approved no
  Call Number UA @ lucian @ c:irua:15801 Serial 3606
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Author Clima, S.; Chen, Y.Y.; Chen, C.Y.; Goux, L.; Govoreanu, B.; Degraeve, R.; Fantini, A.; Jurczak, M.; Pourtois, G.
  Title First-principles thermodynamics and defect kinetics guidelines for engineering a tailored RRAM device Type A1 Journal article
  Year 2016 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 119 Issue 119 Pages 225107
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract Resistive Random Access Memories are among the most promising candidates for the next generation of non-volatile memory. Transition metal oxides such as HfOx and TaOx attracted a lot of attention due to their CMOS compatibility. Furthermore, these materials do not require the inclusion of extrinsic conducting defects since their operation is based on intrinsic ones (oxygen vacancies). Using Density Functional Theory, we evaluated the thermodynamics of the defects formation and the kinetics of diffusion of the conducting species active in transition metal oxide RRAM materials. The gained insights based on the thermodynamics in the Top Electrode, Insulating Matrix and Bottom Electrode and at the interfaces are used to design a proper defect reservoir, which is needed for a low-energy reliable switching device. The defect reservoir has also a direct impact on the retention of the Low Resistance State due to the resulting thermodynamic driving forces. The kinetics of the diffusing conducting defects in the Insulating Matrix determine the switching dynamics and resistance retention. The interface at the Bottom Electrode has a significant impact on the low-current operation and long endurance of the memory cell. Our first-principles findings are confirmed by experimental measurements on fabricated RRAM devices. Published by AIP Publishing.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000378925400035 Publication Date 2016-06-10
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 17 Open Access
  Notes Approved Most recent IF: 2.068
  Call Number UA @ lucian @ c:irua:134651 Serial 4181
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Author Verreck, D.; Verhulst, A.S.; Van de Put, M.; Sorée, B.; Magnus, W.; Mocuta, A.; Collaert, N.; Thean, A.; Groeseneken, G.
  Title Full-zone spectral envelope function formalism for the optimization of line and point tunnel field-effect transistors Type A1 Journal article
  Year 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 118 Issue 118 Pages 134502
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Efficient quantum mechanical simulation of tunnel field-effect transistors (TFETs) is indispensable to allow for an optimal configuration identification. We therefore present a full-zone 15-band quantum mechanical solver based on the envelope function formalism and employing a spectral method to reduce computational complexity and handle spurious solutions. We demonstrate the versatility of the solver by simulating a 40 nm wide In0.53Ga0.47As lineTFET and comparing it to p-n-i-n configurations with various pocket and body thicknesses. We find that the lineTFET performance is not degraded compared to semi-classical simulations. Furthermore, we show that a suitably optimized p-n-i-n TFET can obtain similar performance to the lineTFET. (C) 2015 AIP Publishing LLC.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000362668400025 Publication Date 2015-10-01
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 9 Open Access
  Notes ; D. Verreck acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). This work was supported by imec's Industrial Affiliation Program. ; Approved Most recent IF: 2.068; 2015 IF: 2.183
  Call Number UA @ lucian @ c:irua:128765 Serial 4183
Permanent link to this record
 

 
Author Van de Put, M.L.; Vandenberghe, W.G.; Sorée, B.; Magnus, W.; Fischetti, M.V.
  Title Inter-ribbon tunneling in graphene: An atomistic Bardeen approach Type A1 Journal article
  Year 2016 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 119 Issue 119 Pages 214306
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract A weakly coupled system of two crossed graphene nanoribbons exhibits direct tunneling due to the overlap of the wavefunctions of both ribbons. We apply the Bardeen transfer Hamiltonian formalism, using atomistic band structure calculations to account for the effect of the atomic structure on the tunneling process. The strong quantum-size confinement of the nanoribbons is mirrored by the one-dimensional character of the electronic structure, resulting in properties that differ significantly from the case of inter-layer tunneling, where tunneling occurs between bulk two-dimensional graphene sheets. The current-voltage characteristics of the inter-ribbon tunneling structures exhibit resonance, as well as stepwise increases in current. Both features are caused by the energetic alignment of one-dimensional peaks in the density-of-states of the ribbons. Resonant tunneling occurs if the sign of the curvature of the coupled energy bands is equal, whereas a step-like increase in the current occurs if the signs are opposite. Changing the doping modulates the onset-voltage of the effects as well as their magnitude. Doping through electrostatic gating makes these structures promising for application towards steep slope switching devices. Using the atomistic empirical pseudopotentials based Bardeen transfer Hamiltonian method, inter-ribbon tunneling can be studied for the whole range of two-dimensional materials, such as transition metal dichalcogenides. The effects of resonance and of step-like increases in the current we observe in graphene ribbons are also expected in ribbons made from these alternative two-dimensional materials, because these effects are manifestations of the one-dimensional character of the density-of-states. Published by AIP Publishing.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000378923100022 Publication Date 2016-06-07
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 6 Open Access
  Notes ; ; Approved Most recent IF: 2.068
  Call Number UA @ lucian @ c:irua:134652 Serial 4198
Permanent link to this record
 

 
Author Yagmurcukardes, M.; Sahin, H.; Kang, J.; Torun, E.; Peeters, F.M.; Senger, R.T.
  Title Pentagonal monolayer crystals of carbon, boron nitride, and silver azide Type A1 Journal article
  Year 2015 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 118 Issue 118 Pages 104303
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract In this study, we present a theoretical investigation of structural, electronic, and mechanical properties of pentagonal monolayers of carbon (p-graphene), boron nitride (p-B2N4 and p-B4N2), and silver azide (p-AgN3) by performing state-of-the-art first principles calculations. Our total energy calculations suggest feasible formation of monolayer crystal structures composed entirely of pentagons. In addition, electronic band dispersion calculations indicate that while p-graphene and p-AgN3 are semiconductors with indirect bandgaps, p-BN structures display metallic behavior. We also investigate the mechanical properties (in-plane stiffness and the Poisson's ratio) of four different pentagonal structures under uniaxial strain. p-graphene is found to have the highest stiffness value and the corresponding Poisson's ratio is found to be negative. Similarly, p-B2N4 and p-B4N2 have negative Poisson's ratio values. On the other hand, the p-AgN3 has a large and positive Poisson's ratio. In dynamical stability tests based on calculated phonon spectra of these pentagonal monolayers, we find that only p-graphene and p-B2N4 are stable, but p-AgN3 and p-B4N2 are vulnerable against vibrational excitations.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000361636900028 Publication Date 2015-09-08
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 79 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. was supported by a FWO Pegasus Long Marie Curie Fellowship. H.S. and R.T.S. acknowledge the support from TUBITAK through Project No. 114F397. ; Approved Most recent IF: 2.068; 2015 IF: 2.183
  Call Number UA @ lucian @ c:irua:128415 Serial 4223
Permanent link to this record
 

 
Author de Sousa, A.A.; Chaves, A.; Pereira, T.A.S.; Farias, G.A.; Peeters, F.M.
  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 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 (down) 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
Permanent link to this record
 

 
Author Frota, D.A.; Chaves, A.; Ferreira, W.P.; Farias, G.A.; Milošević, M.V.
  Title Superconductor-ferromagnet bilayer under external drive : the role of vortex-antivortex matter Type A1 Journal article
  Year 2016 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 119 Issue 119 Pages 093912
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Using advanced Ginzburg-Landau simulations, we study the superconducting state of a thin superconducting film under a ferromagnetic layer, separated by an insulating oxide, in applied external magnetic field and electric current. The taken uniaxial ferromagnet is organized into a series of parallel domains with alternating polarization of out-of-plane magnetization, sufficiently strong to induce vortex-antivortex pairs in the underlying superconductor in absence of other magnetic field. We show the organization of such vortex-antivortex matter into rich configurations, some of which are not matching the periodicity of the ferromagnetic film. The variety of possible configurations is enhanced by applied homogeneous magnetic field, where additional vortices in the superconductor may lower the energy of the system by either annihilating the present antivortices under negative ferromagnetic domains or by lowering their own energy after positioning under positive ferromagnetic domains. As a consequence, both the vortex-antivortex reordering in increasing external field and the evolution of the energy of the system are highly nontrivial. Finally, we reveal the very interesting effects of applied dc electric current on the vortex-antivortex configurations, since resulting Lorentzian force has opposite direction for vortices and antivortices, while direction of the applied current with respect to ferromagnetic domains is of crucial importance for the interaction of the applied and the Meissner current, as well as the consequent vortex-antivortex dynamics-both of which are reflected in the anisotropic critical current of the system. (C) 2016 AIP Publishing LLC.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000372351900018 Publication Date 2016-03-07
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 4 Open Access
  Notes ; This work was supported by the Brazilian agencies CNPq, PRONEX/FUNCAP, and CAPES, and the Research Foundation-Flanders (FWO). ; Approved Most recent IF: 2.068
  Call Number UA @ lucian @ c:irua:133200 Serial 4255
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Author Mohammed, M.; Verhulst, A.S.; Verreck, D.; Van de Put, M.; Simoen, E.; Sorée, B.; Kaczer, B.; Degraeve, R.; Mocuta, A.; Collaert, N.; Thean, A.; Groeseneken, G.
  Title Electric-field induced quantum broadening of the characteristic energy level of traps in semiconductors and oxides Type A1 Journal article
  Year 2016 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 120 Issue 120 Pages 245704
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The trap-assisted tunneling (TAT) current in tunnel field-effect transistors (TFETs) is one of the crucial factors degrading the sub-60 mV/dec sub-threshold swing. To correctly predict the TAT currents, an accurate description of the trap is required. Since electric fields in TFETs typically reach beyond 10(6) V/cm, there is a need to quantify the impact of such high field on the traps. We use a quantum mechanical implementation based on the modified transfer matrix method to obtain the trap energy level. We present the qualitative impact of electric field on different trap configurations, locations, and host materials, including both semiconductors and oxides. We determine that there is an electric-field related trap level shift and level broadening. We find that these electric-field induced quantum effects can enhance the trap emission rates. Published by AIP Publishing.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000392174000028 Publication Date 2016-12-26
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 6 Open Access
  Notes ; This work was supported by imec's Industrial Affiliation Program. D. Verreck acknowledges the support of a PhD stipend from IWT-Vlaanderen. ; Approved Most recent IF: 2.068
  Call Number UA @ lucian @ c:irua:141481 Serial 4593
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Author Torun, E.; Sahin, H.; Cahangirov, S.; Rubio, A.; Peeters, F.M.
  Title Anisotropic electronic, mechanical, and optical properties of monolayer WTe2 Type A1 Journal article
  Year 2016 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume 119 Issue 7 Pages 074307
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Using first-principles calculations, we investigate the electronic, mechanical, and optical properties of monolayer WTe2. Atomic structure and ground state properties of monolayer WTe2 (T-d phase) are anisotropic which are in contrast to similar monolayer crystals of transition metal dichalcogenides, such as MoS2, WS2, MoSe2, WSe2, and MoTe2, which crystallize in the H-phase. We find that the Poisson ratio and the in-plane stiffness is direction dependent due to the symmetry breaking induced by the dimerization of the W atoms along one of the lattice directions of the compound. Since the semimetallic behavior of the T-d phase originates from this W-W interaction (along the a crystallographic direction), tensile strain along the dimer direction leads to a semimetal to semiconductor transition after 1% strain. By solving the Bethe-Salpeter equation on top of single shot G(0)W(0) calculations, we predict that the absorption spectrum of T-d-WTe2 monolayer is strongly direction dependent and tunable by tensile strain. (C) 2016 AIP Publishing LLC.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000375158000022 Publication Date 2016-02-19
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN (down) 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 62 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-V1) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. was supported by a FWO Pegasus Long Marie Curie Fellowship. S.C. and A.R. acknowledge the financial support from the Marie Curie grant FP7-PEOPLE-2013-IEF Project No. 628876, European Research Council (ERC-2010-AdG-267374), Spanish grant (FIS2013-46159-C3-1-P), Grupos Consolidados (IT578-13), and AFOSR Grant No. FA2386-15-1-0006 AOARD 144088, H2020-NMP-2014 project MOSTOPHOS, GA No. SEP-210187476, and COST Action MP1306 (EUSpec). S.C. acknowledges the support from The Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 115F388. ; Approved Most recent IF: 2.068
  Call Number UA @ lucian @ c:irua:144747 Serial 4640
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