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Author | Borkowski, R.; Straub, M.; Ou, Y.; Lefevre, Y.; Jelić, Ž.L.; Lanneer, W.; Kaneda, N.; Mahadevan, A.; Hueckstaedt, V.; van Veen, D.; Houtsma, V.; Coomans, W.; Bonk, R.; Maes, J. | ||||
Title | FLCS-PON : a 100 Gbit/s flexible passive optical network: concepts and field trial | Type | A1 Journal article | ||
Year | 2021 | Publication | Journal Of Lightwave Technology | Abbreviated Journal | J Lightwave Technol |
Volume | 39 | Issue | 16 | Pages | 5314-5324 |
Keywords | A1 Journal article; Mass communications; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We demonstrate concepts and results of a field trial for a flexible-rate passive optical network (FLCS-PON), which delivers bitrates up to 100 Gbit/s and allows for adaptations in the transmission method to match the users' channel conditions and optimize throughput. FLCS-PON builds on top of the hardware ecosystem that will be developed for ITU-T 50 Gbit/s PON and employs three new ingredients: optical network unit (ONU) grouping, flexible modulation format, and flexible forward error correction (FEC) code rate. Together, these techniques take advantage of the optical distribution network (ODN) statistics to realize a system capable of more than twofold throughput increase compared to the upcoming 50 Gbit/s PON, but still able to support a full array of deployed fiber edge cases, which are problematic for legacy PONs. In this paper we explain the concepts behind enabling techniques of FLCS-PON. We then report on a field trial over a deployed fiber infrastructure, using a system consisting of one FLCS-PON OLT and two ONUs. We report both pre- and post-forward-error-correction (post-FEC) performance of our system, demonstrating achievable net bitrate over an operator's fiber infrastructure. We realize a downlink transmission at double the speed of ITU-T 50 Gbit/s PON for ONUs exhibiting lower optical path loss (OPL), while simultaneously continue to support ONUs at high OPLs. We additionally realize a record-high 31.5 dB loss budget for 100 Gbit/s transmission using a direct-detection ONU with an optical preamplifier. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000692209800017 | Publication Date | 2021-08-06 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0733-8724 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.671 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 3.671 | |||
Call Number | UA @ admin @ c:irua:181586 | Serial | 6995 | ||
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Author | Nasirpouri, F.; Engbarth, M.A.; Bending, S.J.; Peter, L.M.; Knittel, A.; Fangohr, H.; Milošević, M.V. | ||||
Title | Three-dimensional ferromagnetic architectures with multiple metastable states | Type | A1 Journal article | ||
Year | 2011 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 98 | Issue | 22 | Pages | 222506,1-222506,3 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We demonstrate controllable dual-bath electrodeposition of nickel on architecture-tunable three-dimensional (3D) silver microcrystals. Magnetic hysteresis loops of individual highly faceted Ag-Ni core-shell elements reveal magnetization reversal that comprises multiple sharp steps corresponding to different stable magnetic states. Finite-element micromagnetic simulations on smaller systems show several jumps during magnetization reversal which correspond to transitions between different magnetic vortex states. Structures of this type could be realizations of an advanced magnetic data storage architecture whereby each element represents one multibit, storing a combination of several conventional bits depending on the overall number of possible magnetic states associated with the 3D core-shell shape. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000291405700044 | Publication Date | 2011-06-03 | |
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 | 8 | Open Access | |
Notes | ; This work was supported by EPSRC in the U.K. under Grant Nos. EP/E039944/1 and EP/E040063/1, DYNAMAG project (EU FP7/2007-2013 Grant No. 233552), and FWO-Vlaanderen. ; | Approved | Most recent IF: 3.411; 2011 IF: 3.844 | ||
Call Number | UA @ lucian @ c:irua:90008 | Serial | 3652 | ||
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Author | Silhanek, A.V.; Kramer, R.G.B.; van de Vondel, J.; Moshchalkov, V.V.; Milošević, M.V.; Berdiyorov, G.R.; Peeters, F.M.; Luccas, R.F.; Puig, T. | ||||
Title | Freezing vortex rivers | Type | A1 Journal article | ||
Year | 2010 | Publication | Physica: C : superconductivity | Abbreviated Journal | Physica C |
Volume | 470 | Issue | 19 | Pages | 726-729 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We demonstrate experimentally and theoretically that the dissipative state at high current densities of superconducting samples with a periodic array of holes consist of flux rivers resulting from a short range attractive interaction between vortices. This dynamically induced vortexvortex attraction results from the migration of quasiparticles out of the vortex core. We have directly visualized the formation of vortex chains by scanning Hall microscopy after freezing the dynamic state by a field cooling procedure at constant bias current. Similar experiments carried out in a sample without holes show no hint of flux river formation. | ||||
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Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000282454400004 | Publication Date | 2010-03-08 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0921-4534; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.404 | Times cited | 4 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 1.404; 2010 IF: 1.415 | ||
Call Number | UA @ lucian @ c:irua:85032 | Serial | 1278 | ||
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Author | Silhanek, A.V.; Milošević, M.V.; Kramer, R.B.G.; Berdiyorov, G.R.; Vondel van de, J.; Luccas, R.F.; Puig, T.; Peeters, F.M.; Moshchalkov, V.V. | ||||
Title | Formation of stripelike flux patterns obtained by freezing kinematic vortices in a superconducting Pb film | Type | A1 Journal article | ||
Year | 2010 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
Volume | 104 | Issue | 1 | Pages | |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We demonstrate experimentally and theoretically that the dissipative state of superconducting samples with a periodic array of holes at high current densities consists of flux rivers resulting from a short-range attractive interaction between vortices. This dynamically induced vortex-vortex attraction results from the migration of quasiparticles out of the vortex core (kinematic vortices). We have directly visualized the formation of vortex chains by scanning Hall probe microscopy after freezing the dynamic state by a field cooling procedure at a constant bias current. Similar experiments carried out in a sample without holes show no hint of flux river formation. We shed light on this nonequilibrium phenomena modeled by time-dependent Ginzburg-Landau simulations. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000273881900033 | Publication Date | 2010-01-07 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0031-9007;1079-7114; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.462 | Times cited | 60 | Open Access | |
Notes | ; This work was supported by Methusalem funding by the Flemish government, the Flemish Science Foundation (FWO-VI), the Belgian Science Policy, and the ESF NES network. A. V. S., G. R. B., and J. V. d. V. acknowledge support from FWO-VI R. F. L. acknowledges support from I3P CSIC program and MAT2008-01022. ; | Approved | Most recent IF: 8.462; 2010 IF: 7.622 | ||
Call Number | UA @ lucian @ c:irua:81009 | Serial | 1265 | ||
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Author | Abakumov, A.M.; Batuk, D.; Hadermann, J.; Rozova, M.G.; Sheptyakov, D.V.; Tsirlin, A.A.; Niermann, D.; Waschowski, F.; Hemberger, J.; Van Tendeloo, G.; Antipov, E.V. | ||||
Title | Antiferroelectric (Pb,Bi)1-xFe1+xO3-y perovskites modulated by crystallographic shear planes | Type | A1 Journal article | ||
Year | 2011 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
Volume | 23 | Issue | 2 | Pages | 255-265 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract ![]() |
We demonstrate for the first time a possibility to vary the anion content in perovskites over a wide range through a long-range-ordered arrangement of crystallographic shear (CS) planes. Anion-deficient perovskites (Pb,Bi)1−xFe1+xO3−y with incommensurately modulated structures were prepared as single phases in the compositional range from Pb0.857Bi0.094Fe1.049O2.572 to Pb0.409Bi0.567Fe1.025O2.796. Using a combination of electron diffraction and high-resolution scanning transmission electron microscopy, we constructed a superspace model describing a periodic arrangement of the CS planes. The model was verified by refinement of the Pb0.64Bi0.32Fe1.04O2.675 crystal structure from neutron powder diffraction data ((3 + 1)D S.G. X2/m(α0γ), X = [1/2,1/2,1/2,1/2], a = 3.9082(1) Å, b = 3.90333(8) Å, c = 4.0900(1) Å, β = 91.936(2)°, q = 0.05013(4)a* + 0.09170(3)c* at T = 700 K, RP = 0.036, RwP = 0.048). The (Pb,Bi)1−xFe1+xO3−y structures consist of perovskite blocks separated by CS planes confined to nearly the (509)p perovskite plane. Along the CS planes, the perovskite blocks are shifted with respect to each other over the 1/2[110]p vector that transforms the corner-sharing connectivity of the FeO6 octahedra in the perovskite framework to an edge-sharing connectivity of the FeO5 pyramids at the CS plane, thus reducing the oxygen content. Variation of the chemical composition in the (Pb,Bi)1−xFe1+xO3−y series occurs mainly because of a changing thickness of the perovskite block between the interfaces, that can be expressed through the components of the q vector as Pb6γ+2αBi1−7γ−αFe1+γ−αO3−3γ−α. The Pb, Bi, and Fe atoms are subjected to strong displacements occurring in antiparallel directions on both sides of the perovskite blocks, resulting in an antiferroelectric-type structure. This is corroborated by the temperature-, frequency-, and field-dependent complex permittivity measurements. Pb0.64Bi0.32Fe1.04O2.675 demonstrates a remarkably high resistivity >0.1 T Ω cm at room temperature and orders antiferromagnetically below TN = 608(10) K. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000286160800018 | Publication Date | 2010-12-23 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0897-4756;1520-5002; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.466 | Times cited | 29 | Open Access | |
Notes | Approved | Most recent IF: 9.466; 2011 IF: 7.286 | |||
Call Number | UA @ lucian @ c:irua:88651 | Serial | 136 | ||
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Author | Turner, S.; Egoavil, R.; Batuk, M.; Abakumov, A.A.; Hadermann, J.; Verbeeck, J.; Van Tendeloo, G. | ||||
Title | Site-specific mapping of transition metal oxygen coordination in complex oxides | Type | A1 Journal article | ||
Year | 2012 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 101 | Issue | 24 | Pages | 241910 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract ![]() |
We demonstrate site-specific mapping of the oxygen coordination number for transition metals in complex oxides using atomically resolved electron energy-loss spectroscopy in an aberration-corrected scanning transmission electron microscope. Pb2Sr2Bi2Fe6O16 contains iron with a constant Fe3+ valency in both octahedral and tetragonal pyramidal coordination and is selected to demonstrate the principle of site-specific coordination mapping. Analysis of the site-specific Fe-L2,3 data reveals distinct variations in the fine structure that are attributed to Fe in a six-fold (octahedron) or five-fold (distorted tetragonal pyramid) oxygen coordination. Using these variations, atomic resolution coordination maps are generated that are in excellent agreement with simulations. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000312490000035 | Publication Date | 2012-12-12 | |
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 | 12 | Open Access | |
Notes | Fwo; Countatoms; Vortex; Esteem 312483; esteem2jra3 ECASJO; | Approved | Most recent IF: 3.411; 2012 IF: 3.794 | ||
Call Number | UA @ lucian @ c:irua:105302UA @ admin @ c:irua:105302 | Serial | 3030 | ||
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Author | Karakulina, O.M.; Demortière, A.; Dachraoui, W.; Abakumov, A.M.; Hadermann, J. | ||||
Title | In Situ Electron Diffraction Tomography Using a Liquid-Electrochemical Transmission Electron Microscopy Cell for Crystal Structure Determination of Cathode Materials for Li-Ion batteries | Type | A1 Journal article | ||
Year | 2018 | Publication | Nano letters | Abbreviated Journal | Nano Lett |
Volume | 18 | Issue | 10 | Pages | 6286-6291 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract ![]() |
We demonstrate that changes in the unit cell structure of lithium battery cathode materials during electrochemical cycling in liquid electrolyte can be determined for particles of just a few hundred nanometers in size using in situ transmission electron microscopy (TEM). The atomic coordinates, site occupancies (including lithium occupancy), and cell parameters of the materials can all be reliably quantified. This was achieved using electron diffraction tomography (EDT) in a sealed electrochemical cell with conventional liquid electrolyte (LP30) and LiFePO4 crystals, which have a well-documented charged structure to use as reference. In situ EDT in a liquid environment cell provides a viable alternative to in situ X-ray and neutron diffraction experiments due to the more local character of TEM, allowing for single crystal diffraction data to be obtained from multiphased powder samples and from submicrometer- to nanometer-sized particles. EDT is the first in situ TEM technique to provide information at the unit cell level in the liquid environment of a commercial TEM electrochemical cell. Its application to a wide range of electrochemical experiments in liquid environment cells and diverse types of crystalline materials can be envisaged. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000447355400024 | Publication Date | 2018-10-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1530-6984 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.712 | Times cited | 12 | Open Access | Not_Open_Access: Available from 08.09.2019 |
Notes | O.M. Karakulina, A.M. Abakumov and J. Hadermann acknowledge support from FWO under grant G040116N. A. Demortière wants to thank the French network on the electrochemical energy storage (RS2E), the Store-Ex Labex, for the financial support. Finally, the Fonds Européen de Développement Régional (FEDER), CNRS, Région Hauts-de-France, and Ministère de l’Education Nationale de l’Enseignement Supérieur et de la Recherche are acknowledged for funding. | Approved | Most recent IF: 12.712 | ||
Call Number | EMAT @ emat @c:irua:154750 | Serial | 5063 | ||
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Author | Kuo, C.-T.; Lin, S.-C.; Ghiringhelli, G.; Peng, Y.; De Luca, G.M.; Di Castro, D.; Betto, D.; Gehlmann, M.; Wijnands, T.; Huijben, M.; Meyer-Ilse, J.; Gullikson, E.; Kortright, J.B.; Vailionis, A.; Gauquelin, N.; Verbeeck, J.; Gerber, T.; Balestrino, G.; Brookes, N.B.; Braicovich, L.; Fadley, C.S. | ||||
Title | Depth-resolved resonant inelastic x-ray scattering at a superconductor/half-metallic-ferromagnet interface through standing wave excitation | Type | A1 Journal article | ||
Year | 2018 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 98 | Issue | 23 | Pages | 235146 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract ![]() |
We demonstrate that combining standing wave (SW) excitation with resonant inelastic x-ray scattering (RIXS) can lead to depth resolution and interface sensitivity for studying orbital and magnetic excitations in correlated oxide heterostructures. SW-RIXS has been applied to multilayer heterostructures consisting of a superconductor La1.85Sr0.15CuO4 (LSCO) and a half-metallic ferromagnet La0.67Sr0.33MnO3 (LSMO). Easily observable SW effects on the RIXS excitations were found in these LSCO/LSMO multilayers. In addition, we observe different depth distribution of the RIXS excitations. The magnetic excitations are found to arise from the LSCO/LSMO interfaces, and there is also a suggestion that one of the dd excitations comes from the interfaces. SW-RIXS measurements of correlated-oxide and other multilayer heterostructures should provide unique layer-resolved insights concerning their orbital and magnetic excitations, as well as a challenge for RIXS theory to specifically deal with interface effects. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000454160800004 | Publication Date | 2018-12-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 5 | Open Access | |
Notes | J.V. and N.G. acknowledge ˝ funding through the GOA project “Solarpaint” of the University of Antwerp. The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ admin @ c:irua:156784 | Serial | 5363 | ||
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Author | van Huis, M.A.; Figuerola, A.; Fang, C.; Béché, A.; Zandbergen, H.W.; Manna, L. | ||||
Title | Letter Chemical transformation of Au-tipped CdS nanorods into AuS/Cd core/shell particles by electron beam irradiation | Type | A1 Journal article | ||
Year | 2011 | Publication | Nano letters | Abbreviated Journal | Nano Lett |
Volume | 11 | Issue | 11 | Pages | 4555-4561 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract ![]() |
We demonstrate that electron irradiation of colloidal CdS nanorods carrying Au domains causes their evolution into AuS/Cd core/shell nanoparticles as a result of a concurrent chemical and morphological transformation. The shrinkage of the CdS nanorods and the growth of the Cd shell around the Au tips are imaged in real time, while the displacement of S atoms from the CdS nanorod to the Au domains is evidenced by high-sensitivity energy-dispersive X-ray (EDX) spectroscopy. The various nanodomains display different susceptibility to the irradiation, which results in nanoconfigurations that are very different from those obtained after thermal annealing. Such physical manipulations of colloidal nanocrystals can be exploited as a tool to access novel nanocrystal heterostructures. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington | Editor | ||
Language | Wos | 000296674700009 | Publication Date | 2011-10-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1530-6984;1530-6992; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.712 | Times cited | 25 | Open Access | |
Notes | Approved | Most recent IF: 12.712; 2011 IF: 13.198 | |||
Call Number | UA @ lucian @ c:irua:93710 | Serial | 1814 | ||
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Author | Vagov, A.; Glaessl, M.; Croitoru, M.D.; Axt, V.M.; Kuhn, T. | ||||
Title | Competition between pure dephasing and photon losses in the dynamics of a dot-cavity system | Type | A1 Journal article | ||
Year | 2014 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 90 | Issue | 7 | Pages | 075309 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We demonstrate that in quantum-dot cavity systems, the interplay between acoustic phonons and photon losses introduces novel features and characteristic dependencies in the system dynamics. In particular, the combined action of both dephasing mechanisms strongly affects the transition from the weak-to the strong-coupling regime as well as the shape of the spectral triplet that represents the quantum-dot occupation in Fourier space. The width of the central peak in the triplet is expected to decrease with rising temperature, while the widths and heights of the side peaks depend nonmonotonically on the dot-cavity coupling. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000341258700002 | Publication Date | 2014-08-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 11 | Open Access | |
Notes | ; We acknowledge fruitful discussions with A. Nazir which helped us to more clearly formulate the relation between our phenomenological approach and the microscopic theory. M.D.C. further acknowledges Alexander von Humboldt and BELSPO grants for support. Financial support from the Deutsche Forschungsgemeinschaft (Grant No. AX 17/7-1) is also gratefully acknowledged. ; | Approved | Most recent IF: 3.836; 2014 IF: 3.736 | ||
Call Number | UA @ lucian @ c:irua:119257 | Serial | 437 | ||
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Author | Bittencourt, C.; Hitchock, A.P.; Ke, X.; Van Tendeloo, G.; Ewels, C.P.; Guttmann, P. | ||||
Title | X-ray absorption spectroscopy by full-field X-ray microscopy of a thin graphite flake: Imaging and electronic structure via the carbon K-edge | Type | A1 Journal article | ||
Year | 2012 | Publication | Beilstein journal of nanotechnology | Abbreviated Journal | Beilstein J Nanotech |
Volume | 3 | Issue | Pages | 345-350 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract ![]() |
We demonstrate that near-edge X-ray-absorption fine-structure spectra combined with full-field transmission X-ray microscopy can be used to study the electronic structure of graphite flakes consisting of a few graphene layers. The flake was produced by exfoliation using sodium cholate and then isolated by means of density-gradient ultracentrifugation. An image sequence around the carbon K-edge, analyzed by using reference spectra for the in-plane and out-of-plane regions of the sample, is used to map and spectrally characterize the flat and folded regions of the flake. Additional spectral features in both π and σ regions are observed, which may be related to the presence of topological defects. Doping by metal impurities that were present in the original exfoliated graphite is indicated by the presence of a pre-edge signal at 284.2 eV. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000303243400001 | Publication Date | 2012-04-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2190-4286; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.127 | Times cited | 15 | Open Access | |
Notes | Approved | Most recent IF: 3.127; 2012 IF: 2.374 | |||
Call Number | UA @ lucian @ c:irua:97703 | Serial | 3924 | ||
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Author | Bittencourt, C.; Ke, X.; Van Tendeloo, G.; Tagmatarchis, N.; Guttmann, P. | ||||
Title | NEXAFS spectromicroscopy of suspended carbon nanohorns | Type | A1 Journal article | ||
Year | 2013 | Publication | Chemical physics letters | Abbreviated Journal | Chem Phys Lett |
Volume | 587 | Issue | Pages | 85-87 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract ![]() |
We demonstrate that near-edge X-ray-absorption fine-structure spectroscopy combined with full-field transmission X-ray microscopy can be used to study the electronic structure of suspended carbon nanohorns. Based on reports of electronic structure calculations additional spectral features observed in the π region of the NEXAFS spectrum recorded on the carbon nanohorns were associated to the presence of the pentagonal rings and the folding of the graphene sheet. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000326104500016 | Publication Date | 2013-09-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0009-2614; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.815 | Times cited | 4 | Open Access | |
Notes | Fp7; Countatoms; | Approved | Most recent IF: 1.815; 2013 IF: 1.991 | ||
Call Number | UA @ lucian @ c:irua:111592 | Serial | 2339 | ||
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Author | Hadermann, J.; Abakumov, A.; Van Rompaey, S.; Perkisas, T.; Filinchuk, Y.; Van Tendeloo, G. | ||||
Title | Crystal structure of a lightweight borohydride from submicrometer crystallites by precession electron diffraction | Type | A1 Journal article | ||
Year | 2012 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
Volume | 24 | Issue | 17 | Pages | 3401-3405 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract ![]() |
We demonstrate that precession electron diffraction at low-dose conditions can be successfully applied for structure analysis of extremely electron-beam-sensitive materials. Using LiBH4 as a test material, complete structural information, including the location of the H atoms, was obtained from submicrometer-sized crystallites. This demonstrates for the first time that, where conventional transmission electron microscopy techniques fail, quantitative precession electron diffraction can provide structural information from submicrometer particles of such extremely electron-beam-sensitive materials as complex lightweight hydrides. We expect the precession electron diffraction technique to be a useful tool for nanoscale investigations of thermally unstable lightweight hydrogen-storage materials. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Washington, D.C. | Editor | ||
Language | Wos | 000308833400012 | Publication Date | 2012-08-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0897-4756;1520-5002; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.466 | Times cited | 17 | Open Access | |
Notes | Approved | Most recent IF: 9.466; 2012 IF: 8.238 | |||
Call Number | UA @ lucian @ c:irua:101845 | Serial | 567 | ||
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Author | Milošević, M.V.; Gillijns, W.; Silhanek, A.V.; Libál, A.; Peeters, F.M.; Moshchalkov, V.V. | ||||
Title | Guided nucleation of superconductivity on a graded magnetic substrate | Type | A1 Journal article | ||
Year | 2010 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 96 | Issue | 3 | Pages | 032503,1-032503,3 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We demonstrate the controlled spatial nucleation of superconductivity in a thin film deposited on periodic arrays of ferromagnetic dots with gradually increasing diameter. The perpendicular magnetization of the dots induces vortex-antivortex molecules in the sample, with the number of (anti)vortices increasing with magnet size. The resulting gradient of antivortex density between the dots predetermines local nucleation of superconductivity in the sample as a function of the applied external field and temperature. In addition, the compensation between the applied magnetic field and the antivortices results in an unprecedented enhancement of the critical temperature. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000273890500034 | Publication Date | 2010-01-22 | |
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 | 15 | Open Access | |
Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-NES program. W. G., A. V. S., and A. L. acknowledge individual support from FWO-Vlaanderen. ; | Approved | Most recent IF: 3.411; 2010 IF: 3.841 | ||
Call Number | UA @ lucian @ c:irua:81504 | Serial | 1400 | ||
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Author | Paul, M.; Kufer, D.; Müller, A.; Brück, S.; Goering, E.; Kamp, M.; Verbeeck, J.; Tian, H.; Van Tendeloo, G.; Ingle, N.J.C.; Sing, M.; Claessen, R. | ||||
Title | Fe3O4/ZnO : a high-quality magnetic oxide-semiconductor heterostructure by reactive deposition | Type | A1 Journal article | ||
Year | 2011 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 98 | Issue | 1 | Pages | 012512,1-012512,3 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract ![]() |
We demonstrate the epitaxial growth of Fe<sub>3</sub>O<sub>4</sub> films on ZnO by a simple reactive deposition procedure using molecular oxygen as an oxidizing agent. X-ray photoelectron spectroscopy results evidence that the iron-oxide surface is nearly stoichiometric magnetite. X-ray diffraction results indicate monocrystalline epitaxy and almost complete structural relaxation. Scanning transmission electron micrographs reveal that the microstructure consists of domains which are separated by antiphase boundaries or twin boundaries. The magnetite films show rather slow magnetization behavior in comparison with bulk crystals probably due to reduced magnetization at antiphase boundaries in small applied fields. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000286009800055 | Publication Date | 2011-01-07 | |
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 | 27 | Open Access | |
Notes | The authors acknowledge financial support by DFG through Forschergruppe FOR 1162. | Approved | Most recent IF: 3.411; 2011 IF: 3.844 | ||
Call Number | UA @ lucian @ c:irua:88653 | Serial | 3532 | ||
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Author | Jannis, D.; Müller-Caspary, K.; Béché, A.; Oelsner, A.; Verbeeck, J. | ||||
Title | Spectroscopic coincidence experiments in transmission electron microscopy | Type | A1 Journal article | ||
Year | 2019 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 114 | Issue | 14 | Pages | 143101 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract ![]() |
We demonstrate the feasibility of coincidence measurements on a conventional transmission electron microscope, revealing the temporal correlation between electron energy loss spectroscopy (EELS) and energy dispersive X-ray (EDX) spectroscopy events. We make use of a delay line detector with ps-range time resolution attached to a modified EELS spectrometer. We demonstrate that coincidence between both events, related to the excitation and deexcitation of atoms in a crystal, provides added information not present in the individual EELS or EDX spectra. In particular, the method provides EELS with a significantly suppressed or even removed background, overcoming the many difficulties with conventional parametric background fitting as it uses no assumptions on the shape of the background, requires no user input and does not suffer from counting noise originating from the background signal. This is highly attractive, especially when low concentrations of elements need to be detected in a matrix of other elements. |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000464450200022 | Publication Date | 2019-04-08 | |
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 | 18 | Open Access | OpenAccess |
Notes | Fonds Wetenschappelijk Onderzoek, G093417 ; Horizon 2020 Framework Programme, 823717 ESTEEM3 ; Helmholtz Association, VH-NG-1327 ; | Approved | Most recent IF: 3.411 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:159155 | Serial | 5168 | ||
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Author | Lombardo, J.; Jelić, Ž.L.; Baumans, X.D.A.; Scheerder, J.E.; Nacenta, J.P.; Moshchalkov, V.V.; Van de Vondel, J.; Kramer, R.B.G.; Milošević, M.V.; Silhanek, A.V. | ||||
Title | In situ tailoring of superconducting junctions via electro-annealing | Type | A1 Journal article | ||
Year | 2018 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 10 | Issue | 4 | Pages | 1987-1996 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We demonstrate the in situ engineering of superconducting nanocircuitry by targeted modulation of material properties through high applied current densities. We show that the sequential repetition of such customized electro-annealing in a niobium (Nb) nanoconstriction can broadly tune the superconducting critical temperature T-c and the normal-state resistance R-n in the targeted area. Once a sizable R-n is reached, clear magneto-resistance oscillations are detected along with a Fraunhofer-like field dependence of the critical current, indicating the formation of a weak link but with further adjustable characteristics. Advanced Ginzburg-Landau simulations fully corroborate this picture, employing the detailed parametrization from the electrical characterization and high resolution electron microscope images of the region within the constriction where the material has undergone amorphization by electro-annealing. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000423355300049 | Publication Date | 2017-12-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.367 | Times cited | 23 | Open Access | |
Notes | ; The authors thank the Fonds de la Recherche Scientifique – FNRS, the ARC grant 13/18-08 for Concerted Research Actions, financed by the French Community of Belgium (Wallonia-Brussels Federation), the Research Foundation – Flanders (FWO-Vlaanderen) and the COST action NanoCoHybri (CA16218). The work is also suppported by Methusalem Funding by the Flemish Government. J. Lombardo acknowledges support from F. R. S.-FNRS (FRIA Research Fellowship). The LANEF framework (ANR-10-LABX-51-01) and the Nanoscience Foundation are acknowledged for their support with mutualized infrastructure. The work of A. V. Silhanek is partially supported by PDR T.0106.16 of the F. R. S.-FNRS. The authors thank the ULg Microscopy facility CAREM for part of the SEM investigations. ; | Approved | Most recent IF: 7.367 | ||
Call Number | UA @ lucian @ c:irua:149315UA @ admin @ c:irua:149315 | Serial | 4937 | ||
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Author | Torun, E.; Paleari, F.; Milošević, M.V.; Wirtz, L.; Sevik, C. | ||||
Title | Intrinsic control of interlayer exciton generation in Van der Waals materials via Janus layers | Type | A1 Journal article | ||
Year | 2023 | Publication | Nano letters | Abbreviated Journal | |
Volume | 23 | Issue | 8 | Pages | 3159-3166 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We demonstrate the possibility of engineering the optical properties of transition metal dichalcogenide heterobilayers when one of the constitutive layers has a Janus structure. We investigate different MoS2@Janus layer combinations using first-principles methods including excitons and exciton-phonon coupling. The direction of the intrinsic electric field from the Janus layer modifies the electronic band alignments and, consequently, the energy separation between dark interlayer exciton states and bright in-plane excitons. We find that in-plane lattice vibrations strongly couple the two states, so that exciton-phonon scattering may be a viable generation mechanism for interlayer excitons upon light absorption. In particular, in the case of MoS2@WSSe, the energy separation of the low-lying interlayer exciton from the in-plane exciton is resonant with the transverse optical phonon modes (40 meV). We thus identify this heterobilayer as a prime candidate for efficient generation of charge-separated electron-hole pairs. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000969732100001 | Publication Date | 2023-04-10 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1530-6984 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 10.8 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 10.8; 2023 IF: 12.712 | |||
Call Number | UA @ admin @ c:irua:196034 | Serial | 8118 | ||
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Author | Niermann, T.; Verbeeck, J.; Lehmann, M. | ||||
Title | Creating arrays of electron vortices | Type | A1 Journal article | ||
Year | 2014 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 136 | Issue | Pages | 165-170 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract ![]() |
We demonstrate the production of an ordered array of electron vortices making use of an electron optical setup consisting of two electrostatic biprisms. The biprism filaments are oriented nearly orthogonal with respect to each other in a transmission electron microscope. Matching the position of the filaments, we can choose to form different topological features in the electron wave. We outline the working principle of the setup and demonstrate fist experimental results. This setup partially bridges the gap between angular momentum carried by electron spin, which is intrinsic and therefore present in any position of the wave, and angular momentum carried by the vortex character of the wave, which can be extrinsic depending on the axis around which it is measured. (C) 2013 Elsevier B.V. All rights reserved. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000327884700021 | Publication Date | 2013-10-15 | |
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 | 9 | Open Access | |
Notes | FP7; Countatoms; Vortex ECASJO_; | Approved | Most recent IF: 2.843; 2014 IF: 2.436 | ||
Call Number | UA @ lucian @ c:irua:112837UA @ admin @ c:irua:112837 | Serial | 538 | ||
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Author | Wu, Z.; Zhai, F.; Peeters, F.M.; Xu, H.Q.; Chang, K. | ||||
Title | Valley-dependent brewster angles and Goos-Hänchen effect in strained graphene | Type | A1 Journal article | ||
Year | 2011 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
Volume | 106 | Issue | 17 | Pages | 176802,1-176802,4 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We demonstrate theoretically how local strains in graphene can be tailored to generate a valley-polarized current. By suitable engineering of local strain profiles, we find that electrons in opposite valleys (K or K′) show different Brewster-like angles and Goos-Hänchen shifts, exhibiting a close analogy with light propagating behavior. In a strain-induced waveguide, electrons in K and K′ valleys have different group velocities, which can be used to construct a valley filter in graphene without the need for any external fields. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000290100300016 | Publication Date | 2011-04-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0031-9007;1079-7114; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.462 | Times cited | 235 | Open Access | |
Notes | ; This work was supported by the NSF of China and the MOST, the Swedish International Development Cooperation Agency (SIDA), and the Belgian Science Policy (IAP). ; | Approved | Most recent IF: 8.462; 2011 IF: 7.370 | ||
Call Number | UA @ lucian @ c:irua:89715 | Serial | 3832 | ||
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Author | Muguerra, H.; Pescheux, A.-C.; Meledin, A.; Van Tendeloo, G.; Soubeyroux, J.-L. | ||||
Title | A La2−xGdxZr2O7layer deposited by chemical solution: a promising seed layer for the fabrication of high Jcand low cost coated conductors | Type | A1 Journal article | ||
Year | 2015 | Publication | Journal of materials chemistry C : materials for optical and electronic devices | Abbreviated Journal | J Mater Chem C |
Volume | 3 | Issue | 3 | Pages | 11766-11772 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract ![]() |
We deposited La2-xGdxZr2O7 seed layers by a chemical solution method on a Ni-5%W substrate to study the influence of these layers on the growth process of a 60 nm-thick La2Zr2O7 layer. We measured the performances of these new buffer layers integrated in a coated conductor with a 300 nm-thick Y0.5Gd0.5Ba2Cu3O7-x layer. For the seed layers{,} we considered two different gadolinium contents (x = 0.2 and x = 0.8) and three different thicknesses for these compositions (20 nm{,} 40 nm{,} and 60 nm). The most promising buffer layer stacks are those with 20 nm of the La1.8Gd0.2Zr2O7 layer or La1.2Gd0.8Zr2O7. Indeed the La2-xGdxZr2O7/La2Zr2O7 films are highly textured{,} similar to a 100 nm-thick La2Zr2O7 layer{,} but their roughness is four times lower. Moreover they contain less and smaller pores in the seed layer than a pure La2Zr2O7 layer. The surface of La2Zr2O7 is also homogenous and crystalline with an orientation deviation from the ideal ?011? (100) direction below 10[degree]. With the 20 nm La2-xGdxZr2O7 seed layers we obtain in the coated conductors an efficiently textured transfer with no gradual degradation from the substrate throughout the superconducting layer. The highest Tc and Jc values are achieved with the La1.8Gd0.2Zr2O7 layer and are{,} respectively{,} 91 K and 1.4 MA cm-2. This trend seems to be due to an improvement of the surface quality of the Ni5%W substrate by the addition of a thin seed layer. Our results offer the potential of the La2-xGdxZr2O7 seed layers as promising alternatives for the classic Ni-5%W/LZO/CeO2/YBCO architectures. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000364826000024 | Publication Date | 2015-10-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2050-7526;2050-7534; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 5.256 | Times cited | 4 | Open Access | |
Notes | This work was performed within the framework of the EUROTAPES project (FP7-NMP.2011.2.2-1 Grant no. 280438), funded by the European Union. The authors also thank L. Porcar and P. Chometon for superconducting transition temperature and critical current density measurements and P. Odier for fruitful discussion. | Approved | Most recent IF: 5.256; 2015 IF: 4.696 | ||
Call Number | c:irua:130181 | Serial | 3968 | ||
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Author | Vanderveken, F.; Tyberkevych, V.; Talmelli, G.; Sorée, B.; Ciubotaru, F.; Adelmann, C. | ||||
Title | Lumped circuit model for inductive antenna spin-wave transducers | Type | A1 Journal article | ||
Year | 2022 | Publication | Scientific reports | Abbreviated Journal | Sci Rep-Uk |
Volume | 12 | Issue | 1 | Pages | 3796-13 |
Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We derive a lumped circuit model for inductive antenna spin-wave transducers in the vicinity of a ferromagnetic medium. The model considers the antenna's Ohmic resistance, its inductance, as well as the additional inductance due to the excitation of ferromagnetic resonance or spin waves in the ferromagnetic medium. As an example, the additional inductance is discussed for a wire antenna on top of a ferromagnetic waveguide, a structure that is characteristic for many magnonic devices and experiments. The model is used to assess the scaling properties and the energy efficiency of inductive antennas. Issues related to scaling antenna transducers to the nanoscale and possible solutions are also addressed. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000826474600050 | Publication Date | 2022-03-08 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2045-2322 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.6 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 4.6 | |||
Call Number | UA @ admin @ c:irua:190001 | Serial | 7180 | ||
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Author | Sorée, B.; Magnus, W.; Pourtois, G. | ||||
Title | Analytical and self-consistent quantum mechanical model for a surrounding gate MOS nanowire operated in JFET mode | Type | A1 Journal article | ||
Year | 2008 | Publication | Journal of computational electronics | Abbreviated Journal | J Comput Electron |
Volume | 7 | Issue | 3 | Pages | 380-383 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract ![]() |
We derive an analytical model for the electrostatics and the drive current in a silicon nanowire operating in JFET mode. We show that there exists a range of nanowire radii and doping densities for which the nanowire JFET satisfies reasonable device characteristics. For thin nanowires we have developed a self-consistent quantum mechanical model to obtain the electronic structure. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | S.l. | Editor | ||
Language | Wos | 000208473800067 | Publication Date | 2008-02-20 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1569-8025;1572-8137; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.526 | Times cited | 70 | Open Access | |
Notes | Approved | Most recent IF: 1.526; 2008 IF: NA | |||
Call Number | UA @ lucian @ c:irua:89504 | Serial | 107 | ||
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Author | Shakouri, K.; Badalyan, S.M.; Peeters, F.M. | ||||
Title | Helical liquid of snake states | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 88 | Issue | 19 | Pages | 195404-195405 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We derive an exact solution to the problem of spin snake states induced in a nonhomogeneous magnetic field by a combined action of the Rashba spin-orbit and Zeeman fields. The electron spin behavior as a function of the cyclotron orbit center position and an external homogeneous magnetic field was obtained. It is shown that in an antisymmetric magnetic field the electron spin in the snake states has only an in-plane projection, perpendicular to the magnetic interface, which vanishes at large positive momenta. Applying an external homogeneous magnetic field adds a finite out-of-plane spin component and simultaneously gaps out the spectral branches, which results in regular beating patterns of the spin current components. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000326820200007 | Publication Date | 2013-11-07 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 3 | Open Access | |
Notes | ; This work was supported by the Methusalem program of the Flemish government and the Flemish Science Foundation (FWO-Vl). ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:112712 | Serial | 1416 | ||
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Author | Tkachenko, D.V.; Sheridan, T.E.; Misko, V.R. | ||||
Title | Dispersion relations for circular single and double dusty plasma chains | Type | A1 Journal article | ||
Year | 2011 | Publication | Physics of plasmas | Abbreviated Journal | Phys Plasmas |
Volume | 18 | Issue | 10 | Pages | 103709,1-103709,10 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We derive dispersion relations for a system of identical particles confined in a two-dimensional annular harmonic well and which interact through a Yukawa potential, e.g., a dusty plasma ring. When the particles are in a single chain (i.e., a one-dimensional ring), we find a longitudinal acoustic mode and a transverse optical mode which show approximate agreement with the dispersion relation for a straight configuration for large radii of the ring. When the radius decreases, the dispersion relations modify: there appears an anticrossing of the modes near the crossing point resulting in a frequency gap between the lower and upper branches of the modified dispersion relations. For the double chain (i.e., a two-dimensional zigzag configuration), the dispersion relation has four branches: longitudinal acoustic and optical and transverse acoustic and optical. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Woodbury, N.Y. | Editor | ||
Language | Wos | 000296529600090 | Publication Date | 2011-10-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1070-664X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.115 | Times cited | 7 | Open Access | |
Notes | ; We acknowledge fruitful discussions with F.M. Peeters, A. Matulis, and W.P. Ferreira. This work was supported by the “Odysseus” program of the Flemish Government and FWO-Vl. ; | Approved | Most recent IF: 2.115; 2011 IF: 2.147 | ||
Call Number | UA @ lucian @ c:irua:94052 | Serial | 738 | ||
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Author | Vagov, A.; Shanenko, A.A.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. | ||||
Title | Two-band superconductors : extended Ginzburg-Landau formalism by a systematic expansion in small deviation from the critical temperature | Type | A1 Journal article | ||
Year | 2012 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 86 | Issue | 14 | Pages | 144514 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We derive the extended Ginzburg-Landau (GL) formalism for a clean s-wave two-band superconductor by employing a systematic expansion of the free-energy functional and the corresponding matrix gap equation in powers of the small deviation from the critical temperature tau = 1 – T/T-c. The two lowest orders of this expansion produce the equation for T-c and the standard GL theory. It is shown that in agreement with previous studies, this two-band GL theory maps onto the single-band GL model and thus fails to describe the difference in the spatial profiles of the two-band condensates. We prove that this difference appears already in the leading correction to the standard GL theory, which constitutes the extended GL formalism. We derive linear differential equations that determine the leading corrections to the band order parameters and magnetic field, discuss the validity of these equations, and consider examples of an important interplay between the band condensates. Finally, we present numerical results for the thermodynamic critical magnetic field and temperature-dependent band gaps for recent materials of interest, which are in very good agreement with those obtained from the full BCS approach in a wide temperature range. To this end, we emphasize the advantages of our extended GL theory in comparison with the often used two-component GL-like model based on an unreconstructed two-band generalization of the Gor'kov derivation. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000309776800001 | Publication Date | 2012-10-12 | |
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 | 44 | Open Access | |
Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vl). Authors are indebted to Y. Singh and R. Prozorov for discussions and for providing recent experimental data. A. V. is grateful to W. Pesch for stimulating discussions and critical comments on this work. ; | Approved | Most recent IF: 3.836; 2012 IF: 3.767 | ||
Call Number | UA @ lucian @ c:irua:101798 | Serial | 3769 | ||
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Author | Chaves, A.; Komendová, L.; Milošević, M.V.; Andrade, J.S.; Farias, G.A.; Peeters, F.M. | ||||
Title | Conditions for nonmonotonic vortex interaction in two-band superconductors | Type | A1 Journal article | ||
Year | 2011 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 83 | Issue | 21 | Pages | 214523-214523,6 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We describe a semianalytic approach to the two-band Ginzburg-Landau theory, which predicts the behavior of vortices in two-band superconductors. We show that the character of the short-range vortex-vortex interaction is determined by the sign of the normal domain-superconductor interface energy, in analogy with the conventional differentiation between type I and type II superconductors. However, we also show that the long-range interaction is determined by a modified Ginzburg-Landau parameter κ*, different from the standard κ of a bulk superconductor. This opens the possibility for nonmonotonic vortex-vortex interaction, which is temperature dependent, and can be further tuned by alterations of the material on the microscopic scale. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000292252300009 | Publication Date | 2011-06-30 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 46 | Open Access | |
Notes | ; Discussions with A. Moreira, A. Shanenko, R. Prozorov, and A. Golubov are gratefully acknowledged. This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the bilateral project FWO-CNPq, CAPES, and PRONEX/CNPq/FUNCAP. ; | Approved | Most recent IF: 3.836; 2011 IF: 3.691 | ||
Call Number | UA @ lucian @ c:irua:90922 | Serial | 477 | ||
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Author | Garcia, J.H.; Covaci, L.; Rappoport, T.G. | ||||
Title | Real-space calculation of the conductivity tensor for disordered topological matter | Type | A1 Journal article | ||
Year | 2015 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
Volume | 114 | Issue | 114 | Pages | 116602 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We describe an efficient numerical approach to calculate the longitudinal and transverse Kubo conductivities of large systems using Bastin's formulation. We expand the Green's functions in terms of Chebyshev polynomials and compute the conductivity tensor for any temperature and chemical potential in a single step. To illustrate the power and generality of the approach, we calculate the conductivity tensor for the quantum Hall effect in disordered graphene and analyze the effect of the disorder in a Chern insulator in Haldane's model on a honeycomb lattice. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000351430600010 | Publication Date | 2015-03-20 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0031-9007;1079-7114; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.462 | Times cited | 69 | Open Access | |
Notes | ; We acknowledge A. R. Hernandez, A. Ferreira, and E. Mucciolo for discussions. T. G. R and J. H. G acknowledge the Brazilian agencies CNPq, FAPERJ, and INCT de Nanoestruturas de Carbono for financial support. L. C. acknowledges the Flemish Science Foundation (FWO-Vlaanderen) for financial support. ; | Approved | Most recent IF: 8.462; 2015 IF: 7.512 | ||
Call Number | c:irua:125467 | Serial | 2827 | ||
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Author | Müller, A.; Milošević, M.V.; Dale, S.E.C.; Engbarth, M.A.; Bending, S.J. | ||||
Title | Magnetization measurements and Ginzburg-Landau simulations of micron-size \beta-tin samples : evidence for an unusual critical behavior of mesoscopic type-I superconductors | Type | A1 Journal article | ||
Year | 2012 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
Volume | 109 | Issue | 19 | Pages | 197003 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract ![]() |
We describe investigations of the largely unexplored field of mesoscopic type-I superconductors. Micromagnetometry and 3D Ginzburg-Landau simulations of our single crystal β-tin samples in this regime reveal size- and temperature-dependent supercritical fields whose behavior is radically different from the bulk critical field HcB. We find that complete suppression of the intermediate state in medium-size samples can result in a surprising reduction of the critical field significantly below HcB. We also reveal an evolution of the superconducting-to-normal phase transition from the expected irreversible first order at low temperatures through the previously unobserved reversible first-order to a second-order transition close to Tc, where the critical field can be many times larger than HcB. Finally, we have identified striking correlations between the mesoscopic Hc3 for nucleation of surface superconductivity and the thermodynamic Hc near Tc. All these observations are entirely unexpected in the conventional type-I picture. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000310853100017 | Publication Date | 2012-11-09 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0031-9007;1079-7114; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.462 | Times cited | 21 | Open Access | |
Notes | ; This work was supported by the EPSRC-UK under Grant No. EP/E039944/1, and the Flemish Science Foundation (FWO). ; | Approved | Most recent IF: 8.462; 2012 IF: 7.943 | ||
Call Number | UA @ lucian @ c:irua:102401 | Serial | 1893 | ||
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Author | Aghaei, M.; Bogaerts, A. | ||||
Title | Flowing Atmospheric Pressure Afterglow for Ambient Ionization: Reaction Pathways Revealed by Modeling | Type | A1 Journal article | ||
Year | 2021 | Publication | Analytical Chemistry | Abbreviated Journal | Anal Chem |
Volume | 93 | Issue | 17 | Pages | 6620-6628 |
Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract ![]() |
We describe the plasma chemistry in a helium flowing atmospheric pressure afterglow (FAPA) used for analytical spectrometry, by means of a quasione-dimensional (1D) plasma chemical kinetics model. We study the effect of typical impurities present in the feed gas, as well as the afterglow in ambient humid air. The model provides the species density profiles in the discharge and afterglow regions and the chemical pathways. We demonstrate that H, N, and O atoms are formed in the discharge region, while the dominant reactive neutral species in the afterglow are O3 and NO. He* and He2* are responsible for Penning ionization of O2, N2, H2O, H2, and N, and especially O and H atoms. Besides, He2+ also contributes to ionization of N2, O2, H2O, and O through charge transfer reactions. From the pool of ions created in the discharge, NO+ and (H2O)3H+ are the dominant ions in the afterglow. Moreover, negatively charged clusters, such as NO3H2O− and NO2H2O−, are formed and their pathway is discussed as well. Our model predictions are in line with earlier observations in the literature about the important reagent ions and provide a comprehensive overview of the underlying pathways. The model explains in detail why helium provides a high analytical sensitivity because of high reagent ion formation by both Penning ionization and charge transfer. Such insights are very valuable for improving the analytical performance of this (and other) ambient desorption/ionization source(s). | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000648505900008 | Publication Date | 2021-05-04 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-2700 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 6.32 | Times cited | Open Access | OpenAccess | |
Notes | Fonds Wetenschappelijk Onderzoek, 6713 ; The authors gratefully acknowledge financial support from the Fonds voor Wetenschappelijk Onderzoek (FWO) grant number 6713. The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (Department EWI), and the UA. The authors also thank J. T. Shelley for providing experimental data for the gas velocity behind the anode disk and before the mass spectrometer interface, to validate our model. | Approved | Most recent IF: 6.32 | ||
Call Number | PLASMANT @ plasmant @c:irua:178126 | Serial | 6762 | ||
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