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Author | Verberck, B.; Tarakina, N.V. | ||||
Title | Tubular fullerenes inside carbon nanotubes : optimal molecular orientation versus tube radius | Type | A1 Journal article | ||
Year | 2011 | Publication | European physical journal : B : condensed matter and complex systems | Abbreviated Journal | Eur Phys J B |
Volume | 80 | Issue | 3 | Pages | 355-362 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | We present an investigation of the orientations and positions of tubular fullerene molecules (C90, ..., C200) encapsulated in single-walled carbon nanotubes (SWCNT), a series of so-called fullerene nanopeapods. We find that increasing the tube radius leads to the following succession of energetically stable regimes: (1) lying molecules positioned on the tube's long axis; (2) tilted molecules on the tube's long axis; and (3) lying molecules shifted away from the tube's long axis. As opposed to C70 and C80 molecules encapsulated in a SWCNT, standing orientations do not develop. Our results are relevant for the possible application of molecular-orientation-dependent electronic properties of fullerene nanopeapods, and also for the interpretation of future experiments on double-walled carbon nanotube formation by annealing fullerene peapod systems. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Berlin | Editor | ||
Language | Wos | 000289576200010 | Publication Date | 2011-03-14 | |
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 | 10 | Open Access | |
Notes | ; This work was financially supported by the Research Foundation – Flanders (FWO-VI). B.V. is a Postdoctoral Fellow of the Research Foundation – Flanders (FWO-VI). ; | Approved | Most recent IF: 1.461; 2011 IF: 1.534 | ||
Call Number | UA @ lucian @ c:irua:89286 | Serial | 3738 | ||
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Author | Ignatova, K.; Vlasov, E.; Seddon, S.D.; Gauquelin, N.; Verbeeck, J.; Wermeille, D.; Bals, S.; Hase, T.P.A.; Arnalds, U.B. | ||||
Title | Phase coexistence induced surface roughness in V2O3/Ni magnetic heterostructures | Type | A1 Journal Article | ||
Year | 2024 | Publication | APL Materials | Abbreviated Journal | |
Volume | 12 | Issue | 4 | Pages | |
Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
Abstract | We present an investigation of the microstructure changes in V2O3 as it goes through its inherent structural phase transition. Using V2O3 films with a well-defined crystal structure deposited by reactive magnetron sputtering on r-plane Al2O3 substrates, we study the phase coexistence region and its impact on the surface roughness of the films and the magnetic properties of overlying Ni magnetic layers in V2O3/Ni hybrid magnetic heterostructures. The simultaneous presence of two phases in V2O3 during its structural phase transition was identified with high resolution x-ray diffraction and led to an increase in surface roughness observed using x-ray reflectivity. The roughness reaches its maximum at the midpoint of the transition. In V2O3/Ni hybrid heterostructures, we find a concomitant increase in the coercivity of the magnetic layer correlated with the increased roughness of the V2O3 surface. The chemical homogeneity of the V2O3 is confirmed through transmission electron microscopy analysis. High-angle annular dark field imaging and electron energy loss spectroscopy reveal an atomically flat interface between Al2O3 and V2O3, as well as a sharp interface between V2O3 and Ni. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 001202661800003 | Publication Date | 2024-04-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2166-532X | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 6.1 | Times cited | Open Access | ||
Notes | This work was supported by the funding from the University of Iceland Research Fund, the Icelandic Research Fund Grant No. 207111. Instrumentation funding from the Icelandic Infrastructure Fund is acknowledged. This work was based on experiments per- formed at the BM28 (XMaS) beamline at the European Synchrotron Radiation Facility, Grenoble, France. XMaS is a National Research Facility funded by the UK EPSRC and managed by the Universi- ties of Liverpool and Warwick. This project has received funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 823717—ESTEEM3. | Approved | Most recent IF: 6.1; 2024 IF: 4.335 | ||
Call Number | EMAT @ emat @c:irua:205569 | Serial | 9120 | ||
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Author | He, Z.B.; Deng, G.; Tian, H.; Xu, Q.; Van Tendeloo, G. | ||||
Title | 90° Rotation of orbital stripes in bilayer manganite PrCa2Mn2O7 studied by in situ transmission electron microscopy | Type | A1 Journal article | ||
Year | 2013 | Publication | Journal of solid state chemistry | Abbreviated Journal | J Solid State Chem |
Volume | 200 | Issue | Pages | 287-293 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We present an in situ transmission electron microscopy study on the half-doped bilayer manganite PrCa2Mn2O7 to reveal the rotation process of the orbital stripes. Between the reported initial and final ordering phases, we identified an intermediate state with two sets of satellite spots to bridge the 90° rotation of the orbital stripes. Furthermore, we determined that the rotation of the orbital stripes does not always occur. Some restricted conditions for the orbital rotation to occur were found and reasons are discussed. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | London | Editor | ||
Language | Wos | 000317158000043 | Publication Date | 2013-02-08 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0022-4596; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.299 | Times cited | 5 | Open Access | |
Notes | Countatoms | Approved | Most recent IF: 2.299; 2013 IF: 2.200 | ||
Call Number | UA @ lucian @ c:irua:106183 | Serial | 20 | ||
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Author | Canossa, S.; Ferrari, E.; Sippel, P.; Fischer, J.K.H.; Pfattner, R.; Frison, R.; Masino, M.; Mas-Torrent, M.; Lunkenheimer, P.; Rovira, C.; Girlando, A. | ||||
Title | Tetramethylbenzidine-TetrafluoroTCNQ (TMB-TCNQF(4)) : a narrow-gap semiconducting salt with room-temperature relaxor ferroelectric behavior | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of Physical Chemistry C | Abbreviated Journal | J Phys Chem C |
Volume | 125 | Issue | 46 | Pages | 25816-25824 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | We present an extension and revision of the spectroscopic and structural data of the mixed-stack charge-transfer (CT) crystal 3,3 ',5,5 '-tetramethylbenzidine-tetrafluorotetracyano-quinodimethane (TMB-TCNQF4), associated with new electric and dielectric measurements. Refinement of synchrotron structural data at low temperature has led to revise the previously reported C2/m structure. The revised structure is P2(1)/m, with two dimerized stacks per unit cell, and is consistent with the low temperature vibrational data. However, polarized Raman data in the low-frequency region also indicate that by increasing temperature above 200 K, the structure presents an increasing degree of disorder, mainly along the stack axis. X-ray diffraction data at room temperature have confirmed that the correct structure is P2(1)/ m -no phase transitions -but did not allow substantiating the presence of disorder. On the other hand, dielectric measurements have evidenced a typical relaxor ferroelectric behavior already at room temperature, with a peak in the real part of dielectric constant epsilon'(T,v) around 200 K and 0.1 Hz. The relaxor behavior is explained in terms of the presence of spin solitons separating domains of opposite polarity that yield to ferroelectric nanodomains. TMB-TCNQF(4) is confirmed to be a narrow-gap band semiconductor (Ea similar to 0.3 eV) with a room-temperature conductivity of similar to 10(-4) Omega(-1) cm(-1). | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000731170500008 | Publication Date | 0000-00-00 | |
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 | Open Access | Not_Open_Access | |
Notes | A.G. thanks Prof. Pascale Foury-Leylekian for very helpful discussions about the crystallographic issues. R.F. thanks Prof. Anthony Linden for his help in the X-ray diffraction data collection. J.K.H.F. and P.L. acknowledge funding from the Deutsche Forschungsgemeinschaft (DFG) via the Transregional Collaborative Research Center TRR80 (Augsburg, Munich). R.P. and M.M.-T. acknowledge support from the Marie Curie Cofund, Beatriu de Pinós Fellowships (Grant nos. AGAUR 2017 BP 00064). This work was also supported by the Spanish Ministry project GENESIS PID2019-111682RBI00, the “Severo Ochoa” Programme for Centers of Excellence in R&D (FUNFUTURE, CEX2019-000917-S), and the Generalitat de Catalunya (2017-SGR-918). The Elettra Synchrotron (CNR Trieste) is acknowledged for granting the beamtime at the single-crystal diffraction beamline XRD1 (Proposal ID 20185483). In Parma, the work has benefited from the equipment and support of the COMP-HUB Initiative, funded by the “Departments of Excellence” program of the | Approved | Most recent IF: 4.536 | ||
Call Number | UA @ admin @ c:irua:184866 | Serial | 7066 | ||
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Author | Anisimovas, E.; Peeters, F.M. | ||||
Title | Negative trions in coupled quantum dots | Type | A1 Journal article | ||
Year | 2004 | Publication | Physica. E: Low-dimensional systems and nanostructures T2 – 15th International Conference on Electronic Properties of, Two-Dimensional Systems (EP2DS-15), JUL 14-18, 2003, Nara, JAPAN | Abbreviated Journal | Physica E |
Volume | 22 | Issue | 1-3 | Pages | 566-569 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | We present an exact diagonalization study of negatively charged excitonic trions in two vertically coupled parabolic quantum dots. The electrons and the hole are confined to different dots. We obtain the energy spectra as a function of inter-dot separation and external magnetic field strength and identify different ground-state angular momentum transitions which are accompanied by abrupt charge redistributions in the dots. (C) 2003 Elsevier B.V. All rights reserved. | ||||
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Publisher | North-Holland | Place of Publication | Amsterdam | Editor | |
Language | Wos | 000221140800137 | Publication Date | 2004-02-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1386-9477; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.221 | Times cited | 1 | Open Access | |
Notes | Approved | Most recent IF: 2.221; 2004 IF: 0.898 | |||
Call Number | UA @ lucian @ c:irua:102771 | Serial | 2292 | ||
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Author | Wiorek, A.; Parrilla, M.; Cuartero, M.; Crespo, G.A. | ||||
Title | Epidermal patch with glucose biosensor : pH and temperature correction toward more accurate sweat analysis during sport practice | Type | A1 Journal article | ||
Year | 2020 | Publication | Analytical Chemistry | Abbreviated Journal | Anal Chem |
Volume | 92 | Issue | 14 | Pages | 10153-10161 |
Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
Abstract | We present an epidermal patch for glucose analysis in sweat incorporating for the first time pH and temperature correction according to local dynamic fluctuations in sweat during on-body tests. This sort of correction is indeed the main novelty of the paper, being crucial toward reliable measurements in every sensor based on an enzymatic element whose activity strongly depends on pH and temperature. The results herein reported for corrected glucose detection during on-body measurements are supported by a two-step validation protocol: with the biosensor operating off- and on-bodily, correlating the results with UV-vis spectrometry and/or ion chromatography. Importantly, the wearable device is a flexible skin patch that comprises a microfluidic cell designed with a sweat collection zone coupled to a fluidic channel in where the needed electrodes are placed: glucose biosensor, pH potentiometric electrode and a temperature sensor. The glucose biosensor presents a linear range of response within the expected physiological levels of glucose in sweat (10-200 mu M), and the calibration parameters are dynamically adjusted to any change in pH and temperature during the sport practice by means of a new “correction approach”. In addition, the sensor displays a fast response time, appropriate selectivity, and excellent reversibility. A total of 9 validated on-body tests are presented: the outcomes revealed a great potential of the wearable glucose sensor toward the provision of reliable physiological data linked to individuals during sport activity. In particular, the developed “correction approach” is expected to impact into the next generation of wearable devices that digitalize physiological activities through chemical information in a trustable manner for both sport and healthcare applications. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000554986200089 | Publication Date | 2020-06-26 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700; 5206-882x | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.4 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 7.4; 2020 IF: 6.32 | |||
Call Number | UA @ admin @ c:irua:175265 | Serial | 7931 | ||
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Author | Bertoni, G.; Beyers, E.; Verbeeck, J.; Mertens, M.; Cool, P.; Vansant, E.F.; Van Tendeloo, G. | ||||
Title | Quantification of crystalline and amorphous content in porous TiO2 samples from electron energy loss spectroscopy | Type | A1 Journal article | ||
Year | 2006 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 106 | Issue | 7 | Pages | 630-635 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA) | ||||
Abstract | We present an efficient method for the quantification of crystalline versus amorphous phase content in mesoporous materials, making use of electron energy loss spectroscopy. The method is based on fitting a superposition of core-loss edges using the maximum likelihood method with measured reference spectra. We apply the method to mesoporous TiO2 samples. We show that the absolute amount of the crystalline phase can be determined with an accuracy below 5%. This method takes also the amorphous phase into account, where standard X-ray diffraction is only quantitative for crystalline phases and not for amorphous phase. (c) 2006 Elsevier B.V.. All rights reserved. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000238479300011 | Publication Date | 2006-04-28 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 83 | Open Access | |
Notes | Iap-V; Goa-2005; Fwo | Approved | Most recent IF: 2.843; 2006 IF: 1.706 | ||
Call Number | UA @ lucian @ c:irua:58823UA @ admin @ c:irua:58823 | Serial | 2741 | ||
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Author | Yampolskii, S.V.; Peeters, F.M. | ||||
Title | Giant vortices in small mesoscopic disks : an approximate description | Type | A1 Journal article | ||
Year | 2002 | Publication | Physica: C : superconductivity | Abbreviated Journal | Physica C |
Volume | 369 | Issue | 1/4 | Pages | 347-350 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We present an approximate description of the giant vortex state in a thin mesoscopic superconducting disk within the phenomenological Ginzburg-Landau approach. Analytical asymptotic expressions for the energies of the states with fixed vorticity are obtained when a small magnetic flux is accumulated in the disk. The spectrum of the lowest Landau levels of such a disk is also discussed. (C) 2001 Elsevier Science B.V. All rights reserved. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000174200000063 | Publication Date | 2002-07-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0921-4534; | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 1.404 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 1.404; 2002 IF: 0.912 | |||
Call Number | UA @ lucian @ c:irua:94930 | Serial | 1342 | ||
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Author | Bal, K.M.; Bogaerts, A.; Neyts, E.C. | ||||
Title | Ensemble-Based Molecular Simulation of Chemical Reactions under Vibrational Nonequilibrium | Type | A1 Journal article | ||
Year | 2020 | Publication | Journal Of Physical Chemistry Letters | Abbreviated Journal | J Phys Chem Lett |
Volume | 11 | Issue | 2 | Pages | 401-406 |
Keywords | A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We present an approach to incorporate the effect of vibrational nonequilibrium in molecular dynamics (MD) simulations. A perturbed canonical ensemble, in which selected modes are excited to higher temperature while all others remain equilibrated at low temperature, is simulated by applying a specifically tailored bias potential. Our method can be readily applied to any (classical or quantum mechanical) MD setup at virtually no additional computational cost and allows the study of reactions of vibrationally excited molecules in nonequilibrium environments such as plasmas. In combination with enhanced sampling methods, the vibrational efficacy and mode selectivity of vibrationally stimulated reactions can then be quantified in terms of chemically relevant observables, such as reaction rates and apparent free energy barriers. We first validate our method for the prototypical hydrogen exchange reaction and then show how it can capture the effect of vibrational excitation on a symmetric SN2 reaction and radical addition on CO2. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000508473400008 | Publication Date | 2020-01-16 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1948-7185 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 5.7 | Times cited | Open Access | ||
Notes | Universiteit Antwerpen; Fonds Wetenschappelijk Onderzoek, 12ZI420N ; Departement Economie, Wetenschap en Innovatie van de Vlaamse Overheid; K.M.B. was funded as a junior postdoctoral fellow of the FWO (Research Foundation − Flanders), Grant 12ZI420N, and through a TOP-BOF research project of the University of Antwerp. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government− department EWI. | Approved | Most recent IF: 5.7; 2020 IF: 9.353 | ||
Call Number | PLASMANT @ plasmant @c:irua:165587 | Serial | 5442 | ||
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Author | Dabaghmanesh, S.; Saniz, R.; Amini, M.N.; Lamoen, D.; Partoens, B. | ||||
Title | Perovskite transparent conducting oxides : an ab initio study | Type | A1 Journal article | ||
Year | 2013 | Publication | Journal of physics : condensed matter | Abbreviated Journal | J Phys-Condens Mat |
Volume | 25 | Issue | 41 | Pages | 415503 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We present an ab initio study of the electronic structure and of the formation energies of various point defects in BaSnO3 and SrGeO3. We show that La and Y impurities substituting Ba or Sr are shallow donors with a preferred 1 + charge state. These defects have a low formation energy within all the suitable equilibrium growth conditions considered. Oxygen vacancies behave as shallow donors as well, preferring the 2 + charge state. Their formation energies, however, are higher in most growth conditions, indicating a limited contribution to conductivity. The calculated electron effective mass in BaSnO3, with a value of 0.21 me, and the very high mobility reported recently in La-doped BaSnO3 single-crystals, suggest that remarkably low scattering rates can be achieved in the latter. In the case of SrGeO3, our results point to carrier density and mobility values in the low range for typical polycrystalline TCOs, in line with experiment. | ||||
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Publisher | Place of Publication | London | Editor | ||
Language | Wos | 000324920400011 | Publication Date | 2013-09-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0953-8984;1361-648X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.649 | Times cited | 17 | Open Access | |
Notes | FWO;Hercules | Approved | Most recent IF: 2.649; 2013 IF: 2.223 | ||
Call Number | UA @ lucian @ c:irua:110495 | Serial | 2574 | ||
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Author | van ‘t Veer, K.; Reniers, F.; Bogaerts, A. | ||||
Title | Zero-dimensional modeling of unpacked and packed bed dielectric barrier discharges: the role of vibrational kinetics in ammonia synthesis | Type | A1 Journal article | ||
Year | 2020 | Publication | Plasma Sources Science & Technology | Abbreviated Journal | Plasma Sources Sci T |
Volume | 29 | Issue | 4 | Pages | 045020 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We present a zero-dimensional plasma kinetics model, including both surface and gas phase kinetics, to determine the role of vibrationally excited states in plasma-catalytic ammonia synthesis. We defined a new method to systematically capture the conditions of dielectric barrier discharges (DBDs), including those found in packed bed DBDs. We included the spatial and temporal nature of such discharges by special consideration of the number of micro-discharges in the model. We introduce a parameter that assigns only a part of the plasma power to the microdischarges, to scale the model conditions from filamentary to uniform plasma. Because of the spatial and temporal behaviour of the micro-discharges, not all micro-discharges occurring in the plasma reactor during a certain gas residence time are affecting the molecules. The fraction of power considered in the model ranges from 0.005 %, for filamentary plasma, to 100 %, for uniform plasma. If vibrational excitation is included in the plasma chemistry, these different conditions, however, yield an ammonia density that is only varying within one order of magnitude. At only 0.05 % of the power put into the uniform plasma component, a model neglecting vibrational excitation clearly does not result in adequate amounts of ammonia. Thus, our new model, which accounts for the concept in which not all the power is deposited by the micro-discharges, but some part may also be distributed in between them, suggests that vibrational kinetic processes are really important in (packed bed) DBDs. Indeed, vibrational excitation takes place in both the uniform plasma between the micro-discharges and in the strong micro-discharges, and is responsible for an increased N2 dissociation rate. This is shown here for plasma-catalytic ammonia synthesis, but might also be valid for other gas conversion applications. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000570241500001 | Publication Date | 2020-04-09 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1361-6595 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.8 | Times cited | Open Access | ||
Notes | This research was supported by the Excellence of Science FWO-FNRS project (FWO grant ID GoF9618n, EOS ID 30505023). The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UAntwerpen. The authors would also like to thank Dr. Fatme Jardali for the discussions on plasma kinetic modelling and Dr. Jungmi Hong and Dr. Anthony B. Murphy for their aid in the calculation of the diffusion coefficients. | Approved | Most recent IF: 3.8; 2020 IF: 3.302 | ||
Call Number | PLASMANT @ plasmant @c:irua:168097 | Serial | 6359 | ||
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Author | Morais, E.; Delikonstantis, E.; Scapinello, M.; Smith, G.; Stefanidis, G.D.; Bogaerts, A. | ||||
Title | Methane coupling in nanosecond pulsed plasmas: Correlation between temperature and pressure and effects on product selectivity | Type | A1 Journal article | ||
Year | 2023 | Publication | Chemical engineering journal | Abbreviated Journal | |
Volume | 462 | Issue | Pages | 142227 | |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We present a zero-dimensional kinetic model to characterise specifically the gas-phase dynamics of methane conversion in a nanosecond pulsed discharge (NPD) plasma reactor. The model includes a systematic approach to capture the nanoscale power discharges and the rapid ensuing changes in electric field, gas and electron temperature, as well as species densities. The effects of gas temperature and reactor pressure on gas conversion and product selectivity are extensively investigated and validated against experimental work. We discuss the important reaction pathways and provide an analysis of the dynamics of the heating and cooling mechanisms. H radicals are found to be the most populous plasma species and they participate in hydrogenation and dehydrogenation reactions, which are the dominant recombination reactions leading to C2H4 and C2H2 as main products (depending on the pressure). |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000983631500001 | Publication Date | 2023-03-02 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1385-8947 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 15.1 | Times cited | Open Access | OpenAccess | |
Notes | We gratefully acknowledge financial support by the Flemish Government through the Moonshot cSBO project “Power-to-Olefins” (P2O; HBC.2020.2620). | Approved | Most recent IF: 15.1; 2023 IF: 6.216 | ||
Call Number | PLASMANT @ plasmant @c:irua:195881 | Serial | 7246 | ||
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Author | Kozák, T.; Bogaerts, A. | ||||
Title | Splitting of CO2 by vibrational excitation in non-equilibrium plasmas : a reaction kinetics model | Type | A1 Journal article | ||
Year | 2014 | Publication | Plasma sources science and technology | Abbreviated Journal | Plasma Sources Sci T |
Volume | 23 | Issue | 4 | Pages | 045004 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | We present a zero-dimensional kinetic model of CO2 splitting in non-equilibrium plasmas. The model includes a description of the CO2 vibrational kinetics (25 vibrational levels up to the dissociation limit of the molecule), taking into account state-specific VT and VV relaxation reactions and the effect of vibrational excitation on other chemical reactions. The model is applied to study the reaction kinetics of CO2 splitting in an atmospheric-pressure dielectric barrier discharge (DBD) and in a moderate-pressure microwave discharge. The model results are in qualitative agreement with published experimental works. We show that the CO2 conversion and its energy efficiency are very different in these two types of discharges, which reflects the important dissociation mechanisms involved. In the microwave discharge, excitation of the vibrational levels promotes efficient dissociation when the specific energy input is higher than a critical value (2.0 eV/molecule under the conditions examined). The calculated energy efficiency of the process has a maximum of 23%. In the DBD, vibrationally excited levels do not contribute significantly to the dissociation of CO2 and the calculated energy efficiency of the process is much lower (5%). | ||||
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Publisher | Institute of Physics | Place of Publication | Bristol | Editor | |
Language | Wos | 000345761500014 | Publication Date | 2014-06-17 | |
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 | 170 | Open Access | |
Notes | Approved | Most recent IF: 3.302; 2014 IF: 3.591 | |||
Call Number | UA @ lucian @ c:irua:117398 | Serial | 3108 | ||
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Author | Michel, K.H.; Verberck, B. | ||||
Title | Theory of the evolution of phonon spectra and elastic constants from graphene to graphite | Type | A1 Journal article | ||
Year | 2008 | Publication | Physical review : B : solid state | Abbreviated Journal | Phys Rev B |
Volume | 78 | Issue | 8 | Pages | 085424,1-085424,17 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We present a unified theory of the phonon dispersions and elastic properties of graphene, graphite, and graphene multilayer systems. Starting from a fifth-nearest-neighbor force-constant model derived from full in-plane phonon dispersions of graphite [Mohr et al., Phys. Rev. B 76, 035439 (2007)], we use Born's long-wave method to calculate the tension and bending coefficients of graphene. Extending the model by interplanar interactions, we study the phonon dispersions and the elastic constants of graphite, and the phonon spectra of graphene multilayers. We find that the inner displacement terms due to sublattice shifts between inequivalent C atoms are quantitatively important in determining the elastomechanical properties of graphene and of graphite. The overall agreement between theory and experiment is very satisfactory. We investigate the evolution from graphene to graphite by studying the increase in the rigid plane optical mode as a function of the number of layers N. At N=10 the graphite value B2g1127 cm−1 is attained within a few percent. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Lancaster, Pa | Editor | ||
Language | Wos | 000259406900106 | Publication Date | 2008-08-21 | |
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 | 72 | Open Access | |
Notes | Approved | Most recent IF: 3.836; 2008 IF: 3.322 | |||
Call Number | UA @ lucian @ c:irua:76527 | Serial | 3622 | ||
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Author | Kozák, T.; Vlček, J. | ||||
Title | A parametric model for reactive high-power impulse magnetron sputtering of films | Type | A1 Journal article | ||
Year | 2016 | Publication | Journal Of Physics D-Applied Physics | Abbreviated Journal | J Phys D Appl Phys |
Volume | 49 | Issue | 49 | Pages | 055202 |
Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
Abstract | We present a time-dependent parametric model for reactive HiPIMS deposition of films. Specific features of HiPIMS discharges and a possible increase in the density of the reactive gas in front of the reactive gas inlets placed between the target and the substrate are considered in the model. The model makes it possible to calculate the compound fractions in two target layers and in one substrate layer, and the deposition rate of films at fixed partial pressures of the reactive and inert gas. A simplified relation for the deposition rate of films prepared using a reactive HiPIMS is presented. We used the model to simulate controlled reactive HiPIMS depositions of stoichiometric ZrO2 films, which were recently carried out in our laboratories with two different configurations of the O2 inlets in front of the sputtered target. The repetition frequency was 500 Hz at the deposition-averaged target power densities of 5 Wcm−2 and 50 Wcm−2 with a pulse-averaged target power density up to 2 kWcm−2. The pulse durations were 50 μs and 200 μs. Our model calculations show that the to-substrate O2 inlet provides systematically lower compound fractions in the target surface layer and higher compound fractions in the substrate surface layer, compared with the to-target O2 inlet. The low compound fractions in the target surface layer (being approximately 10% at the depositionaveraged target power density of 50 Wcm−2 and the pulse duration of 200 μs) result in high deposition rates of the films produced, which are in agreement with experimental values. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000368944100016 | Publication Date | 2015-12-16 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0022-3727 | ISBN | Additional Links | ||
Impact Factor | 2.588 | Times cited | 25 | Open Access | |
Notes | This work was supported by the Czech Science Foundation under Project No. GA14–03875S | Approved | Most recent IF: 2.588 | ||
Call Number | PLASMANT @ plasmant @ | Serial | 3994 | ||
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Author | Verberck, B.; Partoens, B.; Peeters, F.M.; Trauzettel, B. | ||||
Title | Strain-induced band gaps in bilayer graphene | Type | A1 Journal article | ||
Year | 2012 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 85 | Issue | 12 | Pages | 125403-125403,10 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We present a tight-binding investigation of strained bilayer graphene within linear elasticity theory, focusing on the different environments experienced by the A and B carbon atoms of the different sublattices. We find that the inequivalence of the A and B atoms is enhanced by the application of perpendicular strain epsilon(zz), which provides a physical mechanism for opening a band gap, most effectively obtained when pulling the two graphene layers apart. In addition, perpendicular strain introduces electron-hole asymmetry and can result in linear electronic dispersion near the K point. Our findings suggest experimental means for strain-engineered band gaps in bilayer graphene. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000301113200005 | Publication Date | 2012-03-06 | |
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 | 53 | Open Access | |
Notes | ; The authors would like to acknowledge O. Leenaerts, E. Mariani, K. H. Michel, and J. Schelter for useful discussions. B. V. was financially supported by the Flemish Science Foundation (FWO-Vl). This work was financially supported by the ESF program EuroGraphene under projects CONGRAN and ENTS as well as by the DFG. ; | Approved | Most recent IF: 3.836; 2012 IF: 3.767 | ||
Call Number | UA @ lucian @ c:irua:97181 | Serial | 3168 | ||
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Author | Xiao, Y.M.; Xu, W.; Zhang, Y.Y.; Peeters, F.M. | ||||
Title | Optoelectronic properties of ABC-stacked trilayer graphene | Type | A1 Journal article | ||
Year | 2013 | Publication | Physica status solidi: B: basic research | Abbreviated Journal | Phys Status Solidi B |
Volume | 250 | Issue | 1 | Pages | 86-94 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We present a theoretical study on the optoelectronic properties of ABC-stacked trilayer graphene (TLG). The optical conductance and light transmittance are evaluated through using the energy-balance equation derived from the Boltzmann equation for an air/graphene/dielectric-wafer system in the presence of linearly polarized radiation field. The results obtained from two band structure models are examined and compared. For short wavelength radiation, the universal optical conductance sigma(0) = 3e(2)/(4h) can be obtained. Importantly, there exists an optical absorption window in the radiation wavelength range 10-200 mu m, which is induced by different transition energies required for inter- and intra-band optical absorption channels. As a result, we find that the position and width of this window depend sensitively on temperature and carrier density of the system, especially the lower frequency edge. There is a small characteristic absorption peak at about 82 mu m where the largest interband transition states exist in the ABC-stacked TLG model, in contrast to the relatively smooth curves in a simplified model. These theoretical results indicate that TLG has some interesting and important physical properties which can be utilized to realize infrared or THz optoelectronic devices. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Berlin | Editor | ||
Language | Wos | 000313347500011 | Publication Date | 2012-08-08 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0370-1972; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.674 | Times cited | 6 | Open Access | |
Notes | ; This work was supported by the National Natural Science Foundation of China (grant no. 10974206), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. One of us (F.M.P.) was a Specially Appointed Foreign Professor of the Chinese Academy of Sciences. ; | Approved | Most recent IF: 1.674; 2013 IF: 1.605 | ||
Call Number | UA @ lucian @ c:irua:110109 | Serial | 2495 | ||
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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. | ||||
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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 | 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 | Xiao, Y.M.; Xu, W.; Peeters, F.M. | ||||
Title | Infrared to terahertz absorption window in mono- and multi-layer graphene systems | Type | A1 Journal article | ||
Year | 2014 | Publication | Optics communications | Abbreviated Journal | Opt Commun |
Volume | 328 | Issue | Pages | 135-142 | |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We present a theoretical study on optical properties such as optical conductance and light transmission coefficient for mono- and multi-layer graphene systems with AB- and ABC-stacking. Considering an air/graphene/dielectric-water structure, the optical coefficients for those graphene systems are examined and compared. The universal optical conductance sigma(N)(0)=N pi e(2)/(2h) for N layer graphene systems in the visible region is verified. For N 3 layer graphene, the mini-gap induced absorption edges can be observed in odd layers AB-stacked multilayer graphene, where the number and position of the absorption edges are decided by the layers number N. Meanwhile, we can observe the optical absorption windows for those graphene systems in the infrared to terahertz bandwidth (0.2-150 THz). The absorption window is induced by different transition energies required for inter- and intra-band optical absorption channels. We find that the depth and width of the absorption window can be tuned not only via varying temperature and electron density but also by changing the number of graphene layers and the stacking order. These theoretical findings demonstrate that mono- and multi-layer graphene systems can be applied as frequency tunable optoelectronic devices working in infrared to terahertz bandwidth. (C) 2014 Elsevier B.V. All rights reserved. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000336970000022 | Publication Date | 2014-05-14 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0030-4018; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.588 | Times cited | 7 | 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. ; | Approved | Most recent IF: 1.588; 2014 IF: 1.449 | ||
Call Number | UA @ lucian @ c:irua:118364 | Serial | 1666 | ||
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Author | Zhao, C.X.; Xu, W.; Dong, H.M.; Peeters, F.M. | ||||
Title | Plasmon and coupled plasmon-phonon modes in graphene in the presence of a driving electric field | Type | A1 Journal article | ||
Year | 2014 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 89 | Issue | 19 | Pages | 195447 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We present a theoretical study of the plasmon and coupled plasmon-phonon modes induced by intraband electron-electron interaction in graphene in the presence of driving dc electric field. We find that the electric field dependence of these collective excitation modes in graphene differs significantly from that in a conventional two-dimensional electron gas with a parabolic energy spectrum. This is due mainly to the fact that graphene has a linear energy spectrum and the Fermi velocity of electrons in graphene is much larger than the drift velocity of electrons. The obtained results demonstrate that the plasmon and coupled plasmon-phonon modes in graphene can be tuned by applying not only the gate voltage but also the source-to-drain field. The manipulation of plasmon and coupled plasmon-phonon modes by source-to-drain voltage can let graphene be more conveniently applied as an advanced plasmonic material. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000336841000007 | Publication Date | 2014-05-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 9 | Open Access | |
Notes | ; This work was supported by the Ministry of Science and Technology of China (Grant No. 2011YQ130018), the Department of Science and Technology of Yunnan Province, the Chinese Academy of Sciences, and by the National Natural Science Foundation of China (Grant No. 11247002). ; | Approved | Most recent IF: 3.836; 2014 IF: 3.736 | ||
Call Number | UA @ lucian @ c:irua:117764 | Serial | 2642 | ||
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Author | Dong, H.M.; Xu, W.; Zhang, J.; Peeters, F.M.; Vasilopoulos, P. | ||||
Title | Photo-excited carriers and optical conductance and transmission in graphene in the presence of phonon scattering | Type | A1 Journal article | ||
Year | 2010 | Publication | Physica. E: Low-dimensional systems and nanostructures | Abbreviated Journal | Physica E |
Volume | 42 | Issue | 4 | Pages | 748-750 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract | We present a theoretical study of the optoelectronic properties of monolayer graphene. Including the effect of the electron-photon-phonon scattering, we employ the mass- and energy-balance equations derived from the Boltzmann equation to evaluate self-consistently the carrier densities, optical conductance and transmission coefficient in graphene in the presence of linearly polarized radiation field. We find that the photo-excited carrier density can be increased under infrared radiation and depend strongly on radiation intensity and frequency. For short wavelengths (lambda <3 mu m), the universal optical conductance sigma(0) = e(2)/4h is obtained and the light transmittance is about 0.97-0.98. Interestingly, there is an optical absorption window in the range 4-100 mu m which is induced by different transition energies required for inter- and intra-band optical absorption. The position and width of this absorption window depend sensitively on temperature and carrier density of the system. These results are relevant for applications of recently developed graphene devices in advanced optoelectronics such as the infrared photodetectors. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved. | ||||
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Corporate Author | Thesis | ||||
Publisher | North-Holland | Place of Publication | Amsterdam | Editor | |
Language | Wos | 000276541200022 | Publication Date | 2009-11-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1386-9477; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.221 | Times cited | 7 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 2.221; 2010 IF: 1.304 | ||
Call Number | UA @ lucian @ c:irua:99216 | Serial | 2607 | ||
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Author | Dhong, H.M.; Zhang, J.; Peeters, F.M.; Xu, W. | ||||
Title | Optical conductance and transmission in bilayer graphene | Type | A1 Journal article | ||
Year | 2009 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 106 | Issue | 4 | Pages | 043103,1-043103,6 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We present a theoretical study of the optoelectronic properties of bilayer graphene. The optical conductance and transmission coefficient are calculated using the energy-balance equation derived from a Boltzmann equation for an air/graphene/dielectric-wafer system. For short wavelengths (<0.2 µm), we obtain the universal optical conductance =e2/(2). Interestingly, there exists an optical absorption window in the wavelength range 10100 µm, which is induced by different transition energies required for inter- and intra-band optical absorptions in the presence of the MossBurstein effect. As a result, the position and width of this absorption window depend sensitively on temperature, carrier density, and sample mobility of the system. These results are relevant for applications of recently developed graphene devices in advanced optoelectronics such as the infrared photodetectors. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000270083800004 | Publication Date | 2009-08-20 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 11 | Open Access | |
Notes | Approved | Most recent IF: 2.068; 2009 IF: 2.072 | |||
Call Number | UA @ lucian @ c:irua:79315 | Serial | 2472 | ||
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Author | Shi, J.M.; Koenraad, P.M.; van de Stadt, A.F.W.; Peeters, F.M.; Devreese, J.T.; Wolter, J.H. | ||||
Title | Electronic structure of a Si \delta-doped layer in a GaAs/AlxGa1-xAs/GaAs quantum barrier | Type | A1 Journal article | ||
Year | 1996 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
Volume | 54 | Issue | 11 | Pages | 7996-8004 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems | ||||
Abstract | We present a theoretical study of the electronic structure of a heavily Si delta-doped layer in a GaAs/AlxGa1-xAs/GaAs quantum barrier. In this class of structures the effect of DX centers on the electronic properties can be tuned by changing the AlxGa1-xAs barrier width and/or the Al concentration, which leads to a lowering of the DX level with respect to the Fermi energy without disturbing the wave functions much. A self-consistent approach is developed in which the effective confinement potential and the Fermi energy of the system, the energies, the wave functions, and the electron densities of the discrete subbands have been obtained as a function of both the material parameters of the samples and the experimental conditions. The effect of DX centers on such structures at nonzero temperature and under an external pressure is investigated for three different models: (1) the DX(nc)(0) model with no correlation effects, (2) the d(+)/DX(0) model, and (3) the d(+)/DX(-) model with inclusion of correlation effects. In the actual calculation, influences of the background accepters, the discontinuity of the effective mass of the electrons at the interfaces of the different materials, band nonparabolicity, and the exchange-correlation energy of the electrons have been taken into account. We have found that (1) introducing a quantum barrier into delta-doped GaAs makes it possible to control the energy gaps between different electronic; subbands; (2) the electron wave functions are mon spread out when the repellent effect of the barriers is increased as compared to those in delta-doped GaAs; (3) increasing the quantum-barrier height and/or the application of hydrostatic pressure are helpful to experimentally observe the effect of the DX centers through a decrease of the total free-electron density; and (4) the correlation effects of the charged impurities are important for the systems under study. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Lancaster, Pa | Editor | ||
Language | Wos | A1996VL14500066 | Publication Date | 2002-07-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0163-1829;1095-3795; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.736 | Times cited | 11 | Open Access | |
Notes | Approved | no | |||
Call Number | UA @ lucian @ c:irua:104388 | Serial | 1012 | ||
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Author | Zhao, C.X.; Xu, W.; Peeters, F.M. | ||||
Title | Cerenkov emission of terahertz acoustic-phonons from graphene | Type | A1 Journal article | ||
Year | 2013 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 102 | Issue | 22 | Pages | 222101-222104 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We present a theoretical study of the electrical generation of acoustic-phonon emission from graphene at room temperature. The drift velocity (v(x)) and temperature of electrons driven by dc electric field (F-x) are determined by solving self-consistently the momentum-and energy-balance equations derived from the Boltzmann equation. We find that in the presence of impurity, acoustic-and optic-phonon scattering, v(x) can be much larger than the longitudinal (v(l)) and transverse (v(t)) sound velocities in graphene even within the linear response regime. As a result, although the acoustic Cerenkov effect cannot be obviously seen in the analytical formulas, the enhanced acoustic-phonon emission can be observed with increasing F-x when v(x) > v(l) and v > v(t). The frequency of acoustic-phonon emission from graphene can be above 10 THz, which is much higher than that generated from conventional semiconductor systems. This study is pertinent to the application of graphene as hypersonic devices such as terahertz sound sources. (C) 2013 AIP Publishing LLC. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000320621600034 | Publication Date | 2013-06-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 25 | Open Access | |
Notes | ; This work was supported by the National Natural Science Foundation of China (Grant No. 10974206), 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: 3.411; 2013 IF: 3.515 | ||
Call Number | UA @ lucian @ c:irua:109607 | Serial | 305 | ||
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Author | Ball, J.M.; Schryvers, D. | ||||
Title | The analysis of macrotwins in NiAl martensite | Type | A1 Journal article | ||
Year | 2003 | Publication | Journal de physique: 4 T2 – 10th International Conference on Martensitic Transformations, JUN 10-14, 2002, ESPOO, FINLAND | Abbreviated Journal | J Phys Iv |
Volume | 112 | Issue | Part 1 | Pages | 159-162 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We present a theoretical study of macrotwins arising in cubic to tetragonal martensitic transformations. The results help to explain some features of such macrotwins observed in Ni65Al35. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Les Ulis | Editor | ||
Language | Wos | 000186503200024 | Publication Date | 2008-08-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1155-4339; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | Times cited | 11 | Open Access | ||
Notes | Approved | Most recent IF: NA | |||
Call Number | UA @ lucian @ c:irua:103275 | Serial | 3569 | ||
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Author | Dong, H.M.; Xu, W.; Peeters, F.M. | ||||
Title | High-field transport properties of graphene | Type | A1 Journal article | ||
Year | 2011 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
Volume | 110 | Issue | 6 | Pages | 063704,1-063704,6 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We present a theoretical investigation on the transport properties of graphene in the presence of high dc driving fields. Considering electron interactions with impurities and acoustic and optical phonons in graphene, we employ the momentum- and energy-balance equations derived from the Boltzmann equation to self-consistently evaluate the drift velocity and temperature of electrons in graphene in the linear and nonlinear response regimes. We find that the current-voltage relation exhibits distinctly nonlinear behavior, especially in the high electric field regime. Under the action of high-fields the large source-drain (sd) current density can be achieved and the current saturation in graphene is incomplete with increasing the sd voltage Vsd up to 3 V. Moreover, for high fields, Vsd>0.1 V, the heating of electrons in graphene occurs. It is shown that the sd current and electron temperature are sensitive to electron density and lattice temperature in the graphene device. This study is relevant to the application of graphene as high-field nano-electronic devices such as graphene field-effect transistors. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000295619300059 | Publication Date | 2011-09-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0021-8979; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.068 | Times cited | 17 | Open Access | |
Notes | ; This work was supported by the National Natural Science Foundation of China (Grant No. 10974206) and the Department of Science and Technology of Yunnan Province. ; | Approved | Most recent IF: 2.068; 2011 IF: 2.168 | ||
Call Number | UA @ lucian @ c:irua:93614 | Serial | 1433 | ||
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Author | Zhao, C.X.; Xu, W.; Dong, H.M.; Yu, Y.; Qin, H.; Peeters, F.M. | ||||
Title | Enhancement of plasmon-photon coupling in grating coupled graphene inside a Fabry-Perot cavity | Type | A1 Journal article | ||
Year | 2018 | Publication | Solid state communications | Abbreviated Journal | Solid State Commun |
Volume | 280 | Issue | 280 | Pages | 45-49 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We present a theoretical investigation of the plasmon-polariton modes in grating coupled graphene inside a Fabry-Perot cavity. The cavity or photon modes of the device are determined by the Finite Difference Time Domain (FDTD) simulations and the corresponding plasmon-polariton modes are obtained by applying a many-body self-consistent field theory. We find that in such a device structure, the electric field strength of the incident electromagnetic (EM) field can be significantly enhanced near the edges of the grating strips. Thus, the strong coupling between the EM field and the plasmons in graphene can be achieved and the features of the plasmon-polariton oscillations in the structure can be observed. It is found that the frequencies of the plasmon-polariton modes are in the terahertz (THz) bandwidth and depend sensitively on electron density which can be tuned by applying a gate voltage. Moreover, the coupling between the cavity photons and the plasmons in graphene can be further enhanced by increasing the filling factor of the device. This work can help us to gain an in-depth understanding of the THz plasmonic properties of graphene-based structures. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000439059600008 | Publication Date | 2018-06-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0038-1098 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.554 | Times cited | 1 | Open Access | |
Notes | ; This work is supported by the National Natural Science Foundation of China (Grand No. 11604192 and Grant No. 11574319); the Center of Science and Technology of Hefei Academy of Science; the Ministry of Science and Technology of China (Grant No. 2011YQ130018); Department of Science and Technology of Yunnan Province; Chinese Academy of Sciences. ; | Approved | Most recent IF: 1.554 | ||
Call Number | UA @ lucian @ c:irua:152369UA @ admin @ c:irua:152369 | Serial | 5024 | ||
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Author | da Costa, D.R.; Chaves, A.; Zarenia, M.; Pereira, J.M.; Farias, G.A.; Peeters, F.M. | ||||
Title | Geometry and edge effects on the energy levels of graphene quantum rings : a comparison between tight-binding and simplified Dirac models | Type | A1 Journal article | ||
Year | 2014 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 89 | Issue | 7 | Pages | 075418-12 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We present a systematic study of the energy spectra of graphene quantum rings having different geometries and edge types in the presence of a perpendicular magnetic field. Results are obtained within the tight-binding (TB) and Dirac models and we discuss which features of the former can be recovered by using the approximations imposed by the latter. Energy levels of graphene quantum rings obtained by diagonalizing the TB Hamiltonian are demonstrated to be strongly dependent on the rings geometry and the microscopical structure of the edges. This makes it difficult to recover those spectra by the existing theories that are based on the continuum (Dirac) model. Nevertheless, our results show that both approaches (i.e., TB and Dirac model) may provide similar results, but only for very specific combinations of ring geometry and edge types. The results obtained by a simplified model describing an infinitely thin circular Dirac ring show good agreement with those obtained for hexagonal and rhombus armchair graphene rings within the TB model. Moreover, we show that the energy levels of a circular quantum ring with an infinite mass boundary condition obtained within the Dirac model agree with those for a ring defined by a ring-shaped staggered potential obtained within the TB model. | ||||
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Language | Wos | 000332390000009 | Publication Date | 2014-02-18 | |
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ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 56 | 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 Bilateral programme between CNPq and the Flemish Science Foundation (FWO-Vl), and the Brazilian Program Science Without Borders (CsF). ; | Approved | Most recent IF: 3.836; 2014 IF: 3.736 | ||
Call Number | UA @ lucian @ c:irua:115823 | Serial | 1328 | ||
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Author | Peters, J.L.; van den Bos, K.H.W.; Van Aert, S.; Goris, B.; Bals, S.; Vanmaekelbergh, D. | ||||
Title | Ligand-Induced Shape Transformation of PbSe Nanocrystals | Type | A1 Journal article | ||
Year | 2017 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
Volume | 29 | Issue | 29 | Pages | 4122-4128 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We present a study of the relation between the surface chemistry and nanocrystal shape of PbSe nanocrystals with a variable Pb-to-Se stoichiometry and density of oleate ligands. The oleate ligand density and binding configuration are monitored by nuclear magnetic resonance and Fourier transform infrared absorbance spectroscopy, allowing us to quantify the number of surface-attached ligands per NC and the nature of the surface−Pb−oleate configuration. The three-dimensional shape of the PbSe nanocrystals is obtained from high-angle annular dark field scanning transmission electron microscopy combined with an atom counting method. We show that the enhanced oleate capping results in a stabilization and extension of the {111} facets, and a crystal shape transformation from a truncated nanocube to a truncated octahedron. | ||||
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Language | Wos | 000401221700034 | Publication Date | 2017-05-09 | |
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ISSN | 0897-4756 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.466 | Times cited | 45 | Open Access | OpenAccess |
Notes | D.V. acknowledges the European Research Council, ERC advanced grant, Project 692691-First Step, for financial support. We also acknowledge the Dutch FOM programme “Designing Dirac carriers in honeycomb semiconductor superlattices” (FOM Program 152) for financial support. The authors gratefully acknowledge funding from the Research Foundation Flanders (G.036915, G.037413, and funding of a Ph.D. research grant to K.H.W.v.d.B. and a postdoctoral grant to B.G.). S.B. acknowledges the European Research Council, ERC Grant 335078-Colouratom. (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); ECAS_Sara | Approved | Most recent IF: 9.466 | ||
Call Number | EMAT @ emat @ c:irua:143750 c:irua:142983UA @ admin @ c:irua:143750 | Serial | 4571 | ||
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Author | Casavola, M.; van Huis, M.A.; Bals, S.; Lambert, K.; Hens, Z.; Vanmaekelbergh, D. | ||||
Title | Anisotropic cation exchange in PbSe/CdSe core/shell nanocrystals of different geometry | Type | A1 Journal article | ||
Year | 2012 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
Volume | 24 | Issue | 2 | Pages | 294-302 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We present a study of Cd2+-for-Pb2+ exchange in PbSe nanocrystals (NCs) with cube, star, and rod shapes. Prolonged temperature-activated cation exchange results in PbSe/CdSe heterostructured nanocrystals (HNCs) that preserve their specific overall shape, whereas the PbSe core is strongly faceted with dominance of {111} facets. Hence, cation exchange proceeds while the Se anion lattice is preserved, and well-defined {111}/{111} PbSe/CdSe interfaces develop. Interestingly, by quenching the reaction at different stages of the cation exchange new structures have been isolated, such as coreshell nanorods, CdSe rods that contain one or two separated PbSe dots and fully zinc blende CdSe nanorods. The crystallographically anisotropic cation exchange has been characterized by a combined HRTEM/HAADF-STEM study of heterointerface evolution over reaction time and temperature. Strikingly, Pb and Cd are only intermixed at the PbSe/CdSe interface. We propose a plausible model for the cation exchange based on a layer-by-layer replacement of Pb2+ by Cd2+ enabled by a vacancy-assisted cation migration mechanism. | ||||
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Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000299367500008 | Publication Date | 2011-11-17 | |
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ISSN | 0897-4756;1520-5002; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.466 | Times cited | 136 | Open Access | |
Notes | Esteem 026019 | Approved | Most recent IF: 9.466; 2012 IF: 8.238 | ||
Call Number | UA @ lucian @ c:irua:94211 | Serial | 124 | ||
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