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“Coherent three-level mixing in an electronic quantum dot”. Payette C, Yu G, Gupta JA, Austing DG, Nair SV, Partoens B, Amaha S, Tarucha S, Physical review letters 102, 026808 (2009). http://doi.org/10.1103/PhysRevLett.102.026808
Abstract: We observe magnetic-field-induced level mixing and quantum superposition phenomena between three approaching single-particle states in a quantum dot probed via the ground state of an adjacent quantum dot by single-electron resonant tunneling. The mixing is attributed to anisotropy and anharmonicity in realistic dot confining potentials. The pronounced anticrossing and transfer of strengths (both enhancement and suppression) between resonances can be understood with a simple coherent level mixing model. Superposition can lead to the formation of a dark state by complete cancellation of an otherwise strong resonance, an effect resembling coherent population trapping in a three-level-system of quantum and atom optics.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 8.462
Times cited: 26
DOI: 10.1103/PhysRevLett.102.026808
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“Collapse of high field magnetophonon resonance in GaAs-GaAlAs heterojunctions”. Leadley DR, Nicholas RJ, Singleton J, Xu W, Peeters FM, Devreese JT, Perenboom JAAJ, van Bockstal L, Herlach F, Harris JJ, Foxon CT, Physical review letters 73, 589 (1994). http://doi.org/10.1103/PhysRevLett.73.589
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Impact Factor: 7.512
Times cited: 24
DOI: 10.1103/PhysRevLett.73.589
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“Collective cyclotron modes in high mobility two-dimensional hole systems in GaAs-(Ga,Al)As heterojunctions: 1: experiments at low magnetic fields and theory”. Cole BE, Peeters FM, Ardavan A, Hill SO, Singleton J, Batty W, Chamberlain JM, Polisskii A, Henini M, Cheng T, Journal of physics : condensed matter 9, 3163 (1997)
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.649
Times cited: 20
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“Collective cyclotron modes in high mobility two-dimensional hole systems in GaAs-(Ga,Al)As heterojunctions: 2: experiments at magnetic fields of up to forty Tesla”. Cole BE, Batty W, Singleton J, Chamberlain JM, Li L, van Bockstal L, Imanaka Y, Shimamoto Y, Miura N, Peeters FM, Henini M, Cheng T, Journal of physics : condensed matter 9, 4887 (1997)
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.649
Times cited: 5
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“Collective vortex phases in periodic plus random pinning potential”. Pogosov WV, Misko VR, Zhao HJ, Peeters FM, Physical review : B : solid state 79, 014504 (2009). http://doi.org/10.1103/PhysRevB.79.014504
Abstract: We study theoretically the simultaneous effect of regular and random pinning potentials on the vortex lattice structure at filling factor of 1. This structure is determined by a competition between the square symmetry of regular pinning array, by the intervortex interaction favoring a triangular symmetry, and by the randomness trying to depin vortices from their regular positions. Both analytical and molecular-dynamics approaches are used. We construct a phase diagram of the system in the plane of regular and random pinning strengths and determine typical vortex lattice defects appearing in the system due to the disorder. We find that the total disordering of the vortex lattice can occur either in one step or in two steps. For instance, in the limit of weak pinning, a square lattice of pinned vortices is destroyed in two steps. First, elastic chains of depinned vortices appear in the film; but the vortex lattice as a whole remains still pinned by the underlying square array of regular pinning sites. These chains are composed into fractal-like structures. In a second step, domains of totally depinned vortices are generated and the vortex lattice depins from regular array.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 14
DOI: 10.1103/PhysRevB.79.014504
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“Collisional-radiative model for the sputtered copper atoms and ions in a direct current argon glow discharge”. Bogaerts A, Gijbels R, Carman RJ, Spectrochimica acta: part B : atomic spectroscopy 53, 1679 (1998). http://doi.org/10.1016/S0584-8547(98)00201-8
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 71
DOI: 10.1016/S0584-8547(98)00201-8
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“Colloid size distributions in ion implanted glass”. Nistor LC, van Landuyt J, Barton JD, Hole DE, Skelland ND, Townsend PD, Journal of non-crystalline solids 162, 217 (1993). http://doi.org/10.1016/0022-3093(93)91240-4
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.766
Times cited: 63
DOI: 10.1016/0022-3093(93)91240-4
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“Colloidal nickel/gallium nanoalloys obtained from organometallic precursors in conventional organic solvents and in ionic liquids : noble-metal-free alkyne semihydrogenation catalysts”. Schütte K, Doddi A, Kroll C, Meyer H, Wiktor C, Gemel C, Van Tendeloo G, Fischer RA, Janiak C, Nanoscale 6, 5532 (2014). http://doi.org/10.1039/c4nr00111g
Abstract: Efforts to replace noble-metal catalysts by low-cost alternatives are of constant interest. The organometallic, non-aqueous wet-chemical synthesis of various hitherto unknown nanocrystalline Ni/Ga intermetallic materials and the use of NiGa for the selective semihydrogenation of alkynes to alkenes are reported. Thermal co-hydrogenolysis of the all-hydrocarbon precursors [Ni(COD)(2)] (COD = 1,5-cyclooctadiene) and GaCp* (Cp* = pentamethylcyclopentadienyl) in high-boiling organic solvents mesitylene and n-decane in molar ratios of 1 : 1, 2 : 3 and 3 : 1 yields the nano-crystalline powder materials of the over-all compositions NiGa, Ni2Ga3 and Ni3Ga, respectively. Microwave induced co-pyrolysis of the same precursors without additional hydrogen in the ionic liquid [BMIm][BF4] (BMIm = 1-butyl-3-methyl-imidazolium) selectively yields the intermetallic phases NiGa and Ni3Ga from the respective 1 : 1 and 3 : 1 molar ratios of the precursors. The obtained materials are characterized by transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), IR, powder X-ray diffraction (PXRD) and atomic absorption spectroscopy (AAS). The single-source precursor [Ni(GaCp*)(PMe3)(3)] with a fixed Ni : Ga stoichiometry of 1 : 1 was employed as well. In comparison with the co-hydrogenolytic dual precursor source approach it turned out to be less practical due to inefficient nickel incorporation caused by the parasitic formation of stable [Ni(PMe3)(4)]. The use of ionic liquid [BMIm][BF4] as a non-conventional solvent to control the reaction and stabilize the nanoparticles proved to be particularly advantageous and stable colloids of the nanoalloys NiGa and Ni3Ga were obtained. A phase-selective Ni/Ga colloid synthesis in conventional solvents and in the presence of surfactants such as hexadecylamine (HDA) was not feasible due to the undesired reactivity of HDA with GaCp* leading to inefficient gallium incorporation. Recyclable NiGa nanoparticles selectively semihydrogenate 1-octyne and diphenylacetylene (tolan) to 1-octene and diphenylethylene, respectively, with a yield of about 90% and selectivities of up to 94 and 87%. Ni-NPs yield alkanes with a selectivity of 97 or 78%, respectively, under the same conditions.
Keywords: A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Impact Factor: 7.367
Times cited: 40
DOI: 10.1039/c4nr00111g
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“The colour of silver stained glass : analytical investigations carried out with XRF, SEM/EDX, TEM and IBA”. Jembrih-Simbürger D, Neelmeijer C, Schalm O, Fredrickx P, Schreiner M, De Vis K, Mäder M, Schryvers D, Caen J, Journal of analytical atomic spectrometry 17, 321 (2002). http://doi.org/10.1039/b111024c
Abstract: Glass treated on its surface with silver compounds and an aluminosilicate, such as ochre or clay, at higher temperatures (between 550 and 650 °C) accepts a wide variety of a yellow colour. It is the aim of this study to investigate the parameters of the manufacturing process affecting the final colour of silver stained glass and to correlate them with the final colour and colour intensity. Therefore, defined mixtures of ochre and a silver compound (AgCl, AgNO3, Ag2SO4, Ag3PO4, Ag2O) were prepared and applied on soda-lime glass. The firing process was modified within the range from 563 to 630 °C and glass samples were analysed after treatment with energy dispersive X-ray fluorescence analysis (EDXRF), scanning electron microscopy (SEM/EDX), transmission electron microscopy (TEM), as well as ion beam analysis (IBA) with an external beam. Within the scope of IBA simultaneous measurements using particle-induced X-ray emission (PIXE), particle-induced gamma-ray emission (PIGE), and Rutherford backscattering spectrometry (RBS) were carried out in order to obtain the thickness of the Ag-rich surface layer and the depth distribution of Ag. By means of TEM the microstructure of the silver particles was visualised. XRF results show that the lowest amount of Ag could be detected on glass samples treated with silver stain mixtures containing AgCl and Ag2O. A low kiln temperature (e.g. 563 °C) results in a higher silver concentration at the surface and lower penetration depths. Furthermore, the results obtained with SEM/EDX at cross-sections of the glass samples could be confirmed by PIXE, PIGE, RBS, and TEM.
Keywords: A1 Journal article; Art; Electron microscopy for materials research (EMAT); AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 3.379
Times cited: 42
DOI: 10.1039/b111024c
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“Columnar defects and irreversibility lines in Ti-based superconductors”. Wahl A, Hervieu M, Van Tendeloo G, Hardy V, Provost J, Groult D, Simon C, Raveau B, Radiation effects and defects in solids 133, 293 (1995)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 0.513
Times cited: 11
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“Combination of CeO2 and PtO2 doping for the strong enhancement of Jc under magnetic field in melt-textured superconductor YBaCuO”. Delamare MP, Hervieu M, Wang J, Provost J, Monot I, Verbist K, Van Tendeloo G, Physica: C : superconductivity 262, 220 (1996). http://doi.org/10.1016/0921-4534(96)00225-0
Abstract: A combination of CeO2 and PtO2 doping has been studied in melt-processed YBa2Cu3O7-x. This study was carried out using an optimized well established MTG process. The cerium-platinum doped samples exhibit a high fishtail effect with a J(c) of 4.3 x 10(4) A/cm(2) under an applied field of 1 T. Microstructural and nanostructural studies have been performed. The 211 and BaCeO3 inclusions are a few micrometers wide and the formation of a metastable nanocrystalline phase (Y4Ba4)Cu-8-x(Ce,Pt)(x)O-20+delta related to the perovskite is detected. The 123 grains show no specific extended defect generated by the doping process. The relationship between structure and properties are discussed.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 0.942
Times cited: 27
DOI: 10.1016/0921-4534(96)00225-0
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“Combined characterization of composite tabular silver halide microcrystals by cryo-EFTEM/EELS and cryo-STEM/EDX techniques”. Oleshko VP, Gijbels RH, van Daele AJ, Jacob WA, Xu Y-E, Wang S-E, Park I-Y, Kang T-S, Microscopy research and technique 42, 108 (1998). http://doi.org/10.1002/(SICI)1097-0029(19980715)42:2<108::AID-JEMT5>3.0.CO;2-P
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 1.147
Times cited: 4
DOI: 10.1002/(SICI)1097-0029(19980715)42:2<108::AID-JEMT5>3.0.CO;2-P
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“Combined characterization of nanostructures by AEM and STM”. Oleshko V, Gijbels R, Jacob W, Alfimov M, Mikrochimica acta: supplementum 13, 435 (1996)
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
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“Combined molecular dynamics: continuum study of phase transitions in bulk metals under ultrashort pulsed laser irradiation”. Wendelen W, Dzhurakhalov AA, Peeters FM, Bogaerts A, The journal of physical chemistry: C : nanomaterials and interfaces 114, 5652 (2010). http://doi.org/10.1021/jp907385n
Abstract: The phase transition processes induced by ultrashort, 100 fs pulsed laser irradiation of Au, Cu, and Ni are studied by means of a combined atomistic-continuum approach. A moderately low absorbed laser fluence range, from 200 to 600 J/m2 is considered to study phase transitions by means of a local and a nonlocal order parameter. At low laser fluences, the occurrence of layer-by-layer evaporation has been observed, which suggests a direct solid to vapor transition. The calculated amount of molten material remains very limited under the conditions studied, especially for Ni. Therefore, our results show that a kinetic equation that describes a direct solid to vapor transition might be the best approach to model laser-induced phase transitions by continuum models. Furthermore, the results provide more insight into the applicability of analytical superheating theories that were implemented in continuum models and help the understanding of nonequilibrium phase transitions.
Keywords: A1 Journal article; Integrated Molecular Plant Physiology Research (IMPRES); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 4.536
Times cited: 2
DOI: 10.1021/jp907385n
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“Combined TiO2/SiO2 mesoporous photocatalysts with location and phase controllable TiO2 nanoparticles”. Beyers E, Biermans E, Ribbens S, de Witte K, Mertens M, Meynen V, Bals S, Van Tendeloo G, Vansant EF, Cool P, Applied catalysis : B : environmental 88, 515 (2009). http://doi.org/10.1016/j.apcatb.2008.10.009
Abstract: Combined TiO2/SiO2 mesoporous materials were prepared by deposition of TiO2 nanoparticles synthesised via the acid-catalysed solgel method. In the first synthesis step a titania solution is prepared, by dissolving titaniumtetraisopropoxide in nitric acid. The influences of the initial titaniumtetraisopropoxide concentration and the temperature of dissolving on the final structural properties were investigated. In the second step of the synthesis, the titania nanoparticles were deposited on a silica support. Here, the influence of the temperature during deposition was studied. The depositions were carried out on two different mesoporous silica supports, SBA-15 and MCF, leading to substantial differences in the catalytic and structural properties. The samples were analysed with N2-sorption, X-ray diffraction (XRD), electron probe microanalysis (EPMA) and transmission electron microscopy (TEM) to obtain structural information, determining the amount of titania, the crystal phase and the location of the titania particles on the mesoporous material (inside or outside the mesoporous channels). The structural differences of the support strongly determine the location of the nanoparticles and the subsequent photocatalytic activity towards the degradation of rhodamine 6G in aqueous solution under UV irradiation.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
Impact Factor: 9.446
Times cited: 69
DOI: 10.1016/j.apcatb.2008.10.009
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“Combining molecular dynamics with Monte Carlo simulations : implementations and applications”. Neyts EC, Bogaerts A, Theoretical chemistry accounts : theory, computation, and modeling 132, 1320 (2013). http://doi.org/10.1007/s00214-012-1320-x
Abstract: In this contribution, we present an overview of the various techniques for combining atomistic molecular dynamics with Monte Carlo simulations, mainly in the context of condensed matter systems, as well as a brief summary of the main accelerated dynamics techniques. Special attention is given to the force bias Monte Carlo technique and its combination with molecular dynamics, in view of promising recent developments, including a definable timescale. Various examples of the application of combined molecular dynamics / Monte Carlo simulations are given, in order to demonstrate the enhanced simulation efficiency with respect to either pure molecular dynamics or Monte Carlo.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 1.89
Times cited: 27
DOI: 10.1007/s00214-012-1320-x
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“Commensurate structural modulation in the charge- and orbitally ordered phase of the quadruple perovskite (NaMn3)Mn4O12”. Prodi A, Daoud-Aladine A, Gozzo F, Schmitt B, Lebedev O, Van Tendeloo G, Gilioli E, Bolzoni F, Aruga-Katori H, Takagi H, Marezio M, Gauzzi A;, Physical review : B : condensed matter and materials physics 90, 180101 (2014). http://doi.org/10.1103/PhysRevB.90.180101
Abstract: By means of synchrotron x-ray and electron diffraction, we studied the structural changes at the charge order transition T-CO = 176 K in the mixed-valence quadruple perovskite (NaMn3)Mn4O12. Below T-CO we find satellite peaks indicating a commensurate structural modulation with the same propagation vector q = ( 1/2,0,-1/2) of the CE magnetic structure that orders at low temperatures, similarly to the case of simple perovskites such as La0.5Ca0.5MnO3. In the present case, the modulated structure, together with the observation of a large entropy change at T-CO, gives evidence of a rare case of full Mn3+/Mn4+ charge and orbital order, consistent with the Goodenough-Kanamori model.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 11
DOI: 10.1103/PhysRevB.90.180101
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“Commensurate vortex configurations in thin superconducting films nanostructured by square lattice of magnetic dots”. Milošević, MV, Peeters FM, Physica: C : superconductivity 404, 246 (2004). http://doi.org/10.1016/j.physc.2003.09.098
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.404
Times cited: 6
DOI: 10.1016/j.physc.2003.09.098
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“Comment on “Tunable spin-injection and magnetoconductance in a novel 2DEG-ferromagnet structure&rdquo, [phys. stat. sol. (b) 235, No. 1, 157-161 (2003)]”. Papp G, Peeters FM, Physica status solidi: B: basic research 241, 222 (2004). http://doi.org/10.1002/pssb.200301941
Abstract: We point out that the predicted strong spin-injection effect by Jiang and Jalil [phys. stat. sol. (b) 235, 157 (2003)] for a double magnetic barrier structure is based on a wrong calculation of the transmission probability. We corrected the result and found no significant spin-injection.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.674
Times cited: 11
DOI: 10.1002/pssb.200301941
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“Comparative analysis of the low-energy He+ ions scattering on Al and Al2O3 surfaces”. Fomin VM, Misko VR, Devreese JT, Brongersma HH, Nuclear Instruments &, Methods In Physics Research Section B-Beam Interactions With Materials And Atoms 145, 545 (1998). http://doi.org/10.1016/S0168-583X(98)00530-8
Keywords: A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Impact Factor: 1.109
Times cited: 9
DOI: 10.1016/S0168-583X(98)00530-8
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“Comparative Hall studies in the electron- and hole-doped manganites La0.33Ca0.67MnO3 and La0.70Ca0.30MnO3”. Gordon I, Wagner P, Das A, Vanacken J, Moshchalkov VV, Bruynseraede Y, Schuddinck W, Van Tendeloo G, Ziese M, Borghs G, Physical review : B : condensed matter and materials physics 62, 11633 (2000). http://doi.org/10.1103/PhysRevB.62.11633
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 18
DOI: 10.1103/PhysRevB.62.11633
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“A comparative investigation of replication techniques used for the study of (S+Au) sensitized AgBr microcrystals”. Buschmann V, Schryvers D, van Landuyt J, van Roost C, de Keyzer R, The journal of imaging science and technology 40, 189 (1996)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 0.349
Times cited: 4
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“A comparative study of carbocyanine dyes measured with TOF-SIMS and other mass spectrometric techniques”. Adriaensen L, Vangaever F, Gijbels R, Applied surface science 231/232, 348 (2004). http://doi.org/10.1016/j.apsusc.2004.03.091
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.387
Times cited: 7
DOI: 10.1016/j.apsusc.2004.03.091
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“Comparative study of electron temperature and excitation temperature in a magnetic pole enhanced-inductively coupled argon plasma”. Khan AW, Jan F, Saeed A, Zaka-ul-Islam M, Abrar M, Khattak NAD, Zakaullah M, Current applied physics 13, 1241 (2013). http://doi.org/10.1016/j.cap.2013.03.016
Abstract: Magnetic Pole Enhanced-Inductively Coupled Plasmas (MaPE-ICPs) in analogy to the conventional ICPs exhibit two modes of operation, depending on the power coupling mechanism, i.e., a low power mode with dominant capacitive coupling (E-mode) and a high power mode with dominant inductive coupling (H-mode). A comparative study of the electron temperature measured by a Langmuir probe (T-e(LP)) and the electron excitation temperature (T-exc(OES)) determined by Optical Emission Spectroscopy (OES) is reported in the two distinct modes of a MaPE-ICP operated in argon. The dependence of T-e(LP), T-exc(OES) and their ratio (T-e(LP)/T-exc(OES)) on applied power (5-50 W) and gas pressure (15-60 mTorr) is explored, and the validity of T-exc(OES) as an alternative diagnostic to T-e(LP) is tested in the two modes of MaPE-ICP. The OES based non-invasive measurement of the plasma parameters such as electron temperature is very useful for plasma processing applications in which probe measurements are limited. (C) 2013 Elsevier B. V. All rights reserved.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 1.971
Times cited: 13
DOI: 10.1016/j.cap.2013.03.016
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“Comparative study of organic dyes with time-of-flight static secondary ion mass spectrometry and related techniques”. Adriaensen L, Vangaever F, Lenaerts J, Gijbels R, Journal of mass spectrometry 40, 615 (2005). http://doi.org/10.1002/jms.832
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 2.422
Times cited: 4
DOI: 10.1002/jms.832
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“Comparison between a radio-frequency and direct current glow discharge in argon by a hybrid Monte Carlo-fluid model for electrons, argon ions and fast argon atoms”. Bogaerts A, Gijbels R, Goedheer W, Spectrochimica acta: part B : atomic spectroscopy 54, 1335 (1999). http://doi.org/10.1016/S0584-8547(99)00080-4
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 11
DOI: 10.1016/S0584-8547(99)00080-4
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“Comparison of argon and neon as discharge gases in a direct current glow discharge: a mathematical simulation”. Bogaerts A, Gijbels R, Spectrochimica acta: part B : atomic spectroscopy 52, 553 (1997)
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 13
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“Comparison of As- and P-based metamorphic buffers for high performance InP heterojunction bipolar transistor and high electron mobility transistor applications”. Lubyshev D, Fastenau JM, Fang X-M, Wu Y, Doss C, Snyder A, Liu WK, Lamb MSM, Bals S, Song C, Journal of vacuum science &, technology. B. Microelectronics and nanometer structures. Processing, measurement and phenomena 22, 1565 (2004). http://doi.org/10.1116/1.1691412
Abstract: Metamorphic buffers (M-buffers) consisting of graded InAlAs or bulk InP were employed for the production of InP-based epiwafers on GaAs substrates by molecular-beam epitaxy. The graded InAlAs is the standard for production metamorphic high electron mobility transistors (M-HEMTs), while the bulk InP offers superior thermal properties for higher current density circuits. The surface morphology and crystal structure of the two M-buffers showed different relaxation mechanisms. The graded InAlAs gave a cross-hatched pattern with nearly full relaxation and very effective dislocation filtering, while the bulk InP had a uniform isotropic surface with dislocations propagating further up towards the active layers. Both types of M-buffers had atomic force microscopy root-mean-square roughness values around 2030 Å. The Hall transport properties of high electron mobility transistors (HEMTs) grown on the InAlAs M-buffer, and a baseline HEMT grown lattice matched on InP, both had room-temperature mobilities >10 000 cm2/V s, while the M-HEMT on the InP M-buffer showed a decrease to 9000 cm2/V s. Similarly, the dc parameters of a double heterojunction bipolar transistor (DHBT) grown on the InAlAs M-buffer were much closer to the baseline heterojunction bipolar transistor than a DHBT grown on the InP M-buffer. A high breakdown voltage of 11.3 V was achieved on an M-DHBT with the InAlAs M-buffer. We speculate that the degradation in device characteristics on the InP M-buffer was related to the incomplete dislocation filtering.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 25
DOI: 10.1116/1.1691412
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“Comparison of calculated and measured optical emission intensities in a direct current argon-copper glow discharge”. Bogaerts A, Donko Z, Kutasi K, Bano G, Pinhao N, Pinheiro M, Spectrochimica acta: part B : atomic spectroscopy 55, 1465 (2000). http://doi.org/10.1016/S0584-8547(00)00253-6
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 33
DOI: 10.1016/S0584-8547(00)00253-6
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“Comparison of electrostatic and electromagnetic simulations for very high frequency plasmas”. Zhang Y-R, Xu X, Zhao S-X, Bogaerts A, Wang Y-N, Physics of plasmas 17, 113512 (2010). http://doi.org/10.1063/1.3519515
Abstract: A two-dimensional self-consistent fluid model combined with the full set of Maxwell equations is developed to investigate an argon capacitively coupled plasma, focusing on the electromagnetic effects on the discharge characteristics at various discharge conditions. The results indicate that there exist distinct differences in plasma characteristics calculated with the so-called electrostatic model (i.e., without taking into account the electromagnetic effects) and the electromagnetic model (which includes the electromagnetic effects), especially at very high frequencies. Indeed, when the excitation source is in the high frequency regime and the electromagnetic effects are taken into account, the plasma density increases significantly and meanwhile the ionization rate evolves to a very different distribution when the electromagnetic effects are dominant. Furthermore, the dependence of the plasma characteristics on the voltage and pressure is also investigated, at constant frequency. It is observed that when the voltage is low, the difference between these two models becomes more obvious than at higher voltages. As the pressure increases, the plasma density profiles obtained from the electromagnetic model smoothly shift from edge-peaked over uniform to a broad maximum in the center. In addition, the edge effect becomes less pronounced with increasing frequency and pressure, and the skin effect rather than the standing-wave effect becomes dominant when the voltage is high.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 2.115
Times cited: 30
DOI: 10.1063/1.3519515
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