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	Author	Bittencourt, C.; Krüger, P.; Lagos, M.J.; Ke, X.; Van Tendeloo, G.; Ewels, C.; Umek, P.; Guttmann, P.
	Title	Towards atomic resolution in sodium titanate nanotubes using near-edge X-ray-absorption fine-structure spectromicroscopy combined with multichannel multiple-scattering calculations			Type	A1 Journal article
	Year	2012	Publication	Beilstein journal of nanotechnology	Abbreviated Journal	Beilstein J Nanotech
	Volume	3	Issue		Pages	789-797
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Recent advances in near-edge X-ray-absorption fine-structure spectroscopy coupled with transmission X-ray microscopy (NEXAFS-TXM) allow large-area mapping investigations of individual nano-objects with spectral resolution up to E/Delta E = 104 and spatial resolution approaching 10 nm. While the state-of-the-art spatial resolution of X-ray microscopy is limited by nanostructuring process constrains of the objective zone plate, we show here that it is possible to overcome this through close coupling with high-level theoretical modelling. Taking the example of isolated bundles of hydrothermally prepared sodium titanate nanotubes ((Na,H)TiNTs) we are able to unravel the complex nanoscale structure from the NEXAFS-TXM data using multichannel multiple-scattering calculations, to the extent of being able to associate specific spectral features in the O K-edge and Ti L-edge with oxygen atoms in distinct sites within the lattice. These can even be distinguished from the contribution of different hydroxyl groups to the electronic structure of the (Na,H)TiNTs.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000311482400001	Publication Date	2012-11-23
	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	13	Open Access
	Notes				Approved	Most recent IF: 3.127; 2012 IF: 2.374
	Call Number	UA @ lucian @ c:irua:105140			Serial	3684
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	Author	Vodolazov, D.Y.; Peeters, F.M.; Hongisto, T.T.; Arutyunov, K.Y.
	Title	Microscopic model for multiple flux transitions in mesoscopic superconducting loops			Type	A1 Journal article
	Year	2006	Publication	Europhysics letters	Abbreviated Journal	Epl-Europhys Lett
	Volume	75	Issue	2	Pages	315-320
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Paris	Editor
	Language		Wos	000238803400020	Publication Date	2006-06-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0295-5075;1286-4854;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	1.957	Times cited	13	Open Access
	Notes				Approved	Most recent IF: 1.957; 2006 IF: 2.229
	Call Number	UA @ lucian @ c:irua:59628			Serial	2028
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	Author	Brammertz, G.; Oueslati, S.; Buffiere, M.; Bekaert, J.; El Anzeery, H.; Messaoud, K.B.; Sahayaraj, S.; Nuytten, T.; Koble, C.; Meuris, M.; Poortmans, J.;
	Title	Investigation of properties limiting efficiency in Cu₂ZnSnSe₄-based solar cells			Type	A1 Journal article
	Year	2015	Publication	IEEE journal of photovoltaics	Abbreviated Journal	Ieee J Photovolt
	Volume	5	Issue	5	Pages	649-655
	Keywords	A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
	Abstract	We have investigated different nonidealities in Cu2ZnSnSe4CdSZnO solar cells with 9.7% conversion efficiency, in order to determine what is limiting the efficiency of these devices. Several nonidealities could be observed. A barrier of about 300 meV is present for electron flow at the absorberbuffer heterojunction leading to a strong crossover behavior between dark and illuminated currentvoltage curves. In addition, a barrier of about 130 meV is present at the Moabsorber contact, which could be reduced to 15 meV by inclusion of a TiN interlayer. Admittance spectroscopy results on the devices with the TiN backside contact show a defect level with an activation energy of 170 meV. Using all parameters extracted by the different characterization methods for simulations of the two-diode model including injection and recombination currents, we come to the conclusion that our devices are limited by the large recombination current in the depletion region. Potential fluctuations are present in the devices as well, but they do not seem to have a special degrading effect on the devices, besides a probable reduction in minority carrier lifetime through enhanced recombination through the band tail defects.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000353524800026	Publication Date	2014-12-19
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2156-3381;2156-3403;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.712	Times cited	13	Open Access
	Notes	; ;			Approved	Most recent IF: 3.712; 2015 IF: 3.165
	Call Number	c:irua:123717			Serial	1734
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	Author	Araizi-Kanoutas, G.; Geessinck, J.; Gauquelin, N.; Smit, S.; Verbeek, X.H.; Mishra, S.K.; Bencok, P.; Schlueter, C.; Lee, T.-L.; Krishnan, D.; Fatermans, J.; Verbeeck, J.; Rijnders, G.; Koster, G.; Golden, M.S.
	Title	Co valence transformation in isopolar LaCoO3/LaTiO3 perovskite heterostructures via interfacial engineering			Type	A1 Journal article
	Year	2020	Publication	Physical review materials	Abbreviated Journal	Phys. Rev. Materials
	Volume	4	Issue	2	Pages	026001
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	We report charge transfer up to a single electron per interfacial unit cell across nonpolar heterointerfaces from the Mott insulator LaTiO3 to the charge transfer insulator LaCoO3. In high-quality bi- and trilayer systems grown using pulsed laser deposition, soft x-ray absorption, dichroism, and scanning transmission electron microscopy-electron energy loss spectroscopy are used to probe the cobalt-3d electron count and provide an element-specific investigation of the magnetic properties. The experiments show the cobalt valence conversion is active within 3 unit cells of the heterointerface, and able to generate full conversion to 3d7 divalent Co, which displays a paramagnetic ground state. The number of LaTiO3/LaCoO3 interfaces, the thickness of an additional, electronically insulating “break” layer between the LaTiO3 and LaCoO3, and the LaCoO3 film thickness itself in trilayers provide a trio of control knobs for average charge of the cobalt ions in LaCoO3, illustrating the efficacy of O−2p band alignment as a guiding principle for property design in complex oxide heterointerfaces.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000513551200007	Publication Date	2020-02-10
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2475-9953	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.4	Times cited	13	Open Access	OpenAccess
	Notes	Nederlandse Organisatie voor Wetenschappelijk Onderzoek; Universiteit Antwerpen; Horizon 2020, 730872 ; Department of Science and Technology, Ministry of Science and Technology, SR/NM/Z-07/2015 ; Jawaharlal Nehru Centre for Advanced Scientific Research;			Approved	Most recent IF: 3.4; 2020 IF: NA
	Call Number	EMAT @ emat @c:irua:167787			Serial	6376
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	Author	Conti, S.; Perali, A.; Peeters, F.M.; Neilson, D.
	Title	Multicomponent screening and superfluidity in gapped electron-hole double bilayer graphene with realistic bands			Type	A1 Journal article
	Year	2019	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	99	Issue	14	Pages	144517
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Superfluidity has recently been reported in double electron-hole bilayer graphene. The multiband nature of the bilayers is important because of the very small band gaps between conduction and valence bands. The long-range nature of the superfluid pairing interaction means that screening must be fully taken into account. We have carried out a systematic mean-field investigation that includes (i) contributions to screening from both intraband and interband excitations, (ii) the low-energy band structure of bilayer graphene with its small band gap and flattened Mexican-hat-like low-energy bands, (iii) the large density of states at the bottom of the bands, (iv) electron-hole pairing in the multibands, and (v) electron-hole pair transfers between the conduction and valence band condensates. We find that the superfluidity strongly modifies the intraband contributions to the screening, but that the interband contributions are unaffected. Unexpectedly, a net effect of the screening is to suppress Josephson-like pair transfers and to confine the superfluid pairing entirely to the conduction-band condensate even for very small band gaps, making the system behave similarly to a one-band superfluid.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000465160000004	Publication Date	2019-04-18
	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	13	Open Access
	Notes	; This work was partially supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl) and the Methusalem Foundation. We thank Mohammad Zarenia and Alfredo VargasParedes for useful discussions. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ admin @ c:irua:159332			Serial	5221
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	Author	Van Pottelberge, R.; Zarenia, M.; Vasilopoulos, P.; Peeters, F.M.
	Title	Graphene quantum dot with a Coulomb impurity : subcritical and supercritical regime			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	24	Pages	245410
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We study the influence of confinement on the atomic collapse due to a Coulomb impurity placed at the center of a graphene quantum dot of radius R. We apply the zigzag or infinite-mass boundary condition and consider both a point-size and a finite-size impurity. As a function of the impurity strength Za, the energy spectra are discrete. In the case of the zigzag boundary condition, the degenerate (with respect to the angular momentum m) zero-energy levels are pulled down in energy as Z alpha increases, and they remain below epsilon = – Z alpha. Our results show that the energy levels exhibit a 1/R dependence in the subcritical regime [Z alpha < \|km + 1/2\|, k = 1 (-1) for the K (K') valley]. In the supercritical regime (Z alpha > \|km + 1/2\|) we find a qualitatively very different behavior where the levels decrease as a function of R in a nonmonotonic manner. While the valley symmetry is preserved in the presence of the impurity, we find that the impurity breaks electron-hole symmetry. We further study the energy spectrum of zigzag quantum dots in gapped graphene. Our results show that as the gap increases, the lowest electron states are pushed into the gap by the impurity.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000403072400005	Publication Date	2017-06-13
	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	13	Open Access
	Notes	; We thank Massoud Ramezani-Masir and Dean Moldovan for fruitful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the Methusalem funding of the Flemish Government, and by the Canadian NSERC Grant No. OGP0121756 (P. V.). ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:144197			Serial	4661
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	Author	Aierken, Y.; Leenaerts, O.; Peeters, F.M.
	Title	Intrinsic magnetism in penta-hexa-graphene: A first-principles study			Type	A1 Journal article
	Year	2016	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	94	Issue	15	Pages	155410
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Recently, several monolayer carbon allotropes have been proposed. The magnetic properties of these metal-free materials are investigated, and we explore a special type of all carbon system having an intrinsic magnetic ground state. The structure is composed of mixing pentagonal and hexagonal rings of carbon atoms, such that the unit cell consists of eleven atoms, where two C atoms each have an unpaired electron each with a local magnetic moment. The antiferromagnetic (AFM) state has a lower energy than the ferromagnetic (FM) one. However, a strain-driven transition to the FM ground state is possible. The application of strain not only lowers the energy of the FM state but it also induces an energy barrier of about 13 meV/(magnetic atom) to protect the FM state from excitation. Our findings based on first-principles calculations will motivate other works on similar metal-free magnetic monolayer materials and will have an impact on their possible applications in spintronic devices.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000385623700006	Publication Date	2016-10-10
	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	13	Open Access
	Notes	; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation-Flanders (FWO) and the Flemish Government-department EWI. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:144641			Serial	4665
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	Author	Shylau, A.A.; Badalyan, S.M.; Peeters, F.M.; Jauho, A.P.
	Title	Electron polarization function and plasmons in metallic armchair graphene nanoribbons			Type	A1 Journal article
	Year	2015	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	91	Issue	91	Pages	205444
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Plasmon excitations in metallic armchair graphene nanoribbons are investigated using the random phase approximation. An exact analytical expression for the polarization function of Dirac fermions is obtained, valid for arbitrary temperature and doping. We find that at finite temperatures, due to the phase space redistribution among inter-band and intra-band electronic transitions in the conduction and valence bands, the full polarization function becomes independent of temperature and position of the chemical potential. It is shown that for a given width of nanoribbon there exists a single plasmon mode whose energy dispersion is determined by the graphene's fine structure constant. In the case of two Coulomb-coupled nanoribbons, this plasmon splits into in-phase and out-of-phase plasmon modes with splitting energy determined by the inter-ribbon spacing.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000355315400007	Publication Date	2015-05-29
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	13	Open Access
	Notes	; The Center for Nanostructured Graphene (CNG) is sponsored by the Danish National Research Foundation (DNRF58). The work at the University of Antwerp was supported by the Flemisch Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. S.M.B. gratefully acknowledges hospitality and support from the Department of Physics at the University of Missouri. ;			Approved	Most recent IF: 3.836; 2015 IF: 3.736
	Call Number	c:irua:126403			Serial	984
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	Author	Çakir, D.; Otalvaro, D.M.; Brocks, G.
	Title	Magnetoresistance in multilayer fullerene spin valves: A first-principles study			Type	A1 Journal article
	Year	2014	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	90	Issue	24	Pages	245404
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Carbon-based molecular semiconductors are explored for application in spintronics because their small spinorbit coupling promises long spin lifetimes. We calculate the electronic transport from first principles through spin valves comprising bi-and tri-layers of the fullerene molecules C-60 and C-70, sandwiched between two Fe electrodes. The spin polarization of the current, and the magnetoresistance depend sensitively on the interactions at the interfaces between the molecules and the metal surfaces. They are much less affected by the thickness of the molecular layers. A high current polarization (CP > 90%) and magnetoresistance (MR > 100%) at small bias can be attained using C-70 layers. In contrast, the current polarization and the magnetoresistance at small bias are vanishingly small for C-60 layers. Exploiting a generalized Julliere model we can trace the differences in spin-dependent transport between C-60 and C-70 layers to differences between the molecule-metal interface states. These states also allow one to interpret the current polarization and the magnetoresistance as a function of the applied bias voltage.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000345875200005	Publication Date	2014-12-02
	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	13	Open Access
	Notes	; ;			Approved	Most recent IF: 3.836; 2014 IF: 3.736
	Call Number	UA @ lucian @ c:irua:122177			Serial	1928
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	Author	Berdiyorov, G.R.; Doria, M.M.; de Romaguera, A.R.C.; Milošević, M.V.; Brandt, E.H.; Peeters, F.M.
	Title	Current-induced cutting and recombination of magnetic superconducting vortex loops in mesoscopic superconductor-ferromagnet heterostructures			Type	A1 Journal article
	Year	2013	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	87	Issue	18	Pages	184508-5
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Vortex loops are generated by the inhomogeneous stray field of a magnetic dipole on top of a current-carrying mesoscopic superconductor. Cutting and recombination processes unfold under the applied drive, resulting in periodic voltage oscillations across the sample. We show that a direct and detectable consequence of the cutting and recombination of these vortex loops in the present setup is the onset of vortices at surfaces where they were absent prior to the application of the external current. The nonlinear dynamics of vortex loops is studied within the time-dependent Ginzburg-Landau theory to describe the profound three-dimensional features of their time evolution.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000319252000008	Publication Date	2013-05-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	13	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-VI) and the bilateral programme between Flanders and Brazil. G.R.B. acknowledges support from FWO-VI. A.R. de C.R. acknowledges CNPq for financial support. ;			Approved	Most recent IF: 3.836; 2013 IF: 3.664
	Call Number	UA @ lucian @ c:irua:109648			Serial	593
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	Author	Muñoz, W.A.; Covaci, L.; Peeters, F.M.
	Title	Tight-binding study of bilayer graphene Josephson junctions			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	86	Issue	18	Pages	184505-184507
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Using highly efficient simulations of the tight-binding Bogoliubov-de-Gennes model, we solved self-consistently for the pair correlation and the Josephson current in a superconducting-bilayer graphene-superconducting Josephson junction. Different doping levels for the non-superconducting link are considered in the short- and long-junction regimes. Self-consistent results for the pair correlation and superconducting current resemble those reported previously for single-layer graphene except at the Dirac point, where remarkable differences in the proximity effect are found, as well as a suppression of the superconducting current in the long-junction regime. Inversion symmetry is broken by considering a potential difference between the layers and we found that the supercurrent can be switched if the junction length is larger than the Fermi length.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000310840400005	Publication Date	2012-11-07
	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	13	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-VI). ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:105149			Serial	3661
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	Author	Zha, G.-Q.; Milošević, M.V.; Zhou, S.-P.; Peeters, F.M.
	Title	Influence of impurities and surface defects on the flux-induced current in mesoscopic d-wave superconducting loops			Type	A1 Journal article
	Year	2011	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	84	Issue	13	Pages	132501-132501,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We investigated the magnetic flux dependence of the supercurrent in mesoscopic d-wave superconducting loops, containing impurities and surface defects, by numerically solving the Bogoliubovde Gennes equations self-consistently. In the presence of impurities, bound states arise close to the Fermi energy. In the case of a single impurity, the flux-induced current is found to be suppressed. This can be different when more impurities are introduced in the sample due to the quantum interference effect, which depends sensitively on the relative position between the impurities. We further analyze the effect of small surface defects at the inner or outer edge of the loop, and show that indentation and bulge defects have pronounced and different effects on the supercurrent.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000295713600002	Publication Date	2011-10-07
	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	13	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl), by Belgian Science Policy (IAP), by National Science Foundation of China (Grant Nos. 10904089 and 60971053), and by research funds under Grant Nos. 20093108120005, S30105, 09JC1406000, and 10zz63. ;			Approved	Most recent IF: 3.836; 2011 IF: 3.691
	Call Number	UA @ lucian @ c:irua:92811			Serial	1623
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	Author	Tadić, M.; Čukarić, N.; Arsoski, V.; Peeters, F.M.
	Title	Excitonic Aharonov-Bohm effect : unstrained versus strained type-I semiconductor nanorings			Type	A1 Journal article
	Year	2011	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	84	Issue	12	Pages	125307-125307,13
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We study how mechanical strain affects the magnetic field dependence of the exciton states in type-I semiconductor nanorings. Strain spatially separates the electron and hole in (In,Ga)As/GaAs nanorings which is beneficial for the occurrence of the excitonic Aharonov-Bohm (AB) effect. In narrow strained (In,Ga)As/GaAs nanorings the AB oscillations in the exciton ground-state energy are due to anticrossings with the first excited state. No such AB oscillations are found in unstrained GaAs/(Al,Ga)As nanorings irrespective of the ring width. Our results are obtained within an exact numerical diagonalization scheme and are shown to be accurately described by a two-level model with off-diagonal coupling t. The later transfer integral expresses the Coulomb coupling between states of electron-hole pairs. We also found that the oscillator strength for exciton recombination in (In,Ga)As/GaAs nanorings exhibits AB oscillations, which are superimposed on a linear increase with magnetic field. Our results agree qualitatively with recent experiments on the excitonic Aharonov-Bohm effect in type-I (In,Ga)As/GaAs nanorings.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000294777400013	Publication Date	2011-09-09
	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	13	Open Access
	Notes	; This work was supported by the Ministry of Education and Science of Serbia, the Flemish Science Foundation (FWO-Vl), the EU NoE: SANDiE, and the Belgian Science Policy (IAP). The calculations were performed on the CalcUA and Seastar computer clusters of the University of Antwerp. ;			Approved	Most recent IF: 3.836; 2011 IF: 3.691
	Call Number	UA @ lucian @ c:irua:92326			Serial	1122
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	Author	Matulis, A.; Masir, M.R.; Peeters, F.M.
	Title	Application of optical beams to electrons in graphene			Type	A1 Journal article
	Year	2011	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	83	Issue	11	Pages	115458-115458,7
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The technique of beam optics is applied to the description of the wave function of Dirac electrons. This approach is illustrated by considering electron transmission through simple nonhomogeneous structures, such as flat and bent p-n junctions and superlattices. We found that a convex p-n junction compresses the beam waist, while a concave interface widens it without loosing its focusing properties. At a flat p-n junction the waist of the transmitted Gaussian beam can be narrowed or widened, depending on the angle of incidence. A general condition is derived for the occurrence of beam collimation in a superlattice which is less stringent than previous discussed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000288896400013	Publication Date	2011-03-29
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	13	Open Access
	Notes	; This research was supported by the Flemish Science Foundation (Grant No. FWO-Vl), by the Belgian Science policy (IAP), and (in part) by the Lithuanian Science Council under project No. MIP-79/2010. ;			Approved	Most recent IF: 3.836; 2011 IF: 3.691
	Call Number	UA @ lucian @ c:irua:89377			Serial	142
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	Author	Peelaers, H.; Partoens, B.; Peeters, F.M.
	Title	Electronic and dynamical properties of Si/Ge core-shell nanowires			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	11	Pages	113411-113411,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Full ab initio techniques are applied to study the electronic and dynamical properties of free standing, hydrogen-passivated Si/Ge core-shell nanowires oriented along the [110] direction. All studied wires exhibit a direct band gap and are found to be structurally stable. The different contributions of the core and shell atoms to the phonon spectra are identified. The acoustic phonon velocities and the frequencies of some typical optical modes are compared with those of pure Si and Ge nanowires. These depend either on the concentration or on the type of core material. Optical modes are hardened and longitudinal acoustic velocities are softened with decreasing wire diameter.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000282270000001	Publication Date	2010-09-29
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	13	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and NOI-BOF (University of Antwerp). ;			Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:85421			Serial	995
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	Author	Tsirlin, A.A.; Abakumov, A.M.; Van Tendeloo, G.; Rosner, H.
	Title	Interplay of atomic displacement in the quantum magnet (CuCI)LaNb₂O₇			Type	A1 Journal article
	Year	2010	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	82	Issue	5	Pages	054107,1-054107,12
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	We report on the crystal structure of the quantum magnet CuClLaNb2O7 that was controversially described with respect to its structural organization and magnetic behavior. Using high-resolution synchrotron powder x-ray diffraction, electron diffraction, transmission electron microscopy, and band-structure calculations, we solve the room-temperature structure of this compound -CuClLaNb2O7 and find two high-temperature polymorphs. The -CuClLaNb2O7 phase, stable above 640 K, is tetragonal with asub=3.889 Å, csub =11.738 Å, and the space group P4/mmm. In the -CuClLaNb2O7 structure, the Cu and Cl atoms are randomly displaced from the special positions along the 100 directions. The phase asub2asubcsub, space group Pbmm and the phase 2asub2asubcsub, space group Pbam are stable between 640 K and 500 K and below 500 K, respectively. The structural changes at 500 and 640 K are identified as order-disorder phase transitions. The displacement of the Cl atoms is frozen upon the → transformation while a cooperative tilting of the NbO6 octahedra in the phase further eliminates the disorder of the Cu atoms. The low-temperature -CuClLaNb2O7 structure thus combines the two types of the atomic displacements that interfere due to the bonding between the Cu atoms and the apical oxygens of the NbO6 octahedra. The precise structural information resolves the controversy between the previous computation-based models and provides the long-sought input for understanding CuClLaNb2O7 and related compounds with unusual magnetic properties.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000280849400001	Publication Date	2010-08-12
	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	13	Open Access
	Notes				Approved	Most recent IF: 3.836; 2010 IF: 3.774
	Call Number	UA @ lucian @ c:irua:83991			Serial	1706
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	Author	Zha, G.-Q.; Milošević, M.V.; Zhou, S.-P.; Peeters, F.M.
	Title	Magnetic flux periodicity in mesoscopic d-wave symmetric and asymmetric superconducting loops			Type	A1 Journal article
	Year	2009	Publication	Physical review : B : solid state	Abbreviated Journal	Phys Rev B
	Volume	80	Issue	14	Pages	144501,1-144501,5
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The magnetic flux dependence of energy and supercurrent in mesoscopic d-wave symmetric and asymmetric superconducting loops is investigated by numerically solving the Bogoliubov-de Gennes equations self-consistently. For square loops, we find an hc/e-flux periodicity in energy and supercurrent and demonstrate that the flux periodicity is sensitive to the hole size and the superconducting pairing strength as well as temperature. The hc/2e-periodic behavior can be restored almost entirely when we displace the central hole sufficiently out of the center of the sample. In rectangular loops, the discrete current-carrying low-energy spectrum can exist for an odd winding number of the order parameter.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000271351500085	Publication Date	2009-10-15
	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	13	Open Access
	Notes				Approved	Most recent IF: 3.836; 2009 IF: 3.475
	Call Number	UA @ lucian @ c:irua:79994			Serial	1879
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	Author	Szafran, B.; Nowak, M.P.; Bednarek, S.; Chwiej, T.; Peeters, F.M.
	Title	Selective suppression of Dresselhaus or Rashba spin-orbit coupling effects by the Zeeman interaction in quantum dots			Type	A1 Journal article
	Year	2009	Publication	Physical review : B : solid state	Abbreviated Journal	Phys Rev B
	Volume	79	Issue	23	Pages	235303,1-235303,13
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We study single- and two-electron parabolic quantum dots in the presence of linear Dresselhaus and Rashba spin-orbit interactions. Contributions of both types of spin-orbit coupling are investigated in the context of the spin polarization of the system at high magnetic fields. We demonstrate that for negative Landé factors the effect of the Dresselhaus coupling is suppressed at high magnetic field, which for structures without inversion asymmetry leads to a completely spin-polarized system and a strict antisymmetry of the wave functions with respect to the interchange of spatial-electron coordinates. For negative Landé factor the Rashba coupling is preserved at high field and consequently the spin polarization of the systems as well as the spatial antisymmetry of the two-electron wave function remain approximate.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000267699500073	Publication Date	2009-06-02
	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	13	Open Access
	Notes				Approved	Most recent IF: 3.836; 2009 IF: 3.475
	Call Number	UA @ lucian @ c:irua:77691			Serial	2969
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	Author	Vodolazov, D.Y.; Golubovic, D.S.; Peeters, F.M.; Moshchalkov, V.V.
	Title	Enhancement and decrease of critical current due to suppression of superconductivity by a magnetic field			Type	A1 Journal article
	Year	2007	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	76	Issue	13	Pages	134505,1-7
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000250619800084	Publication Date	2007-10-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	13	Open Access
	Notes				Approved	Most recent IF: 3.836; 2007 IF: 3.172
	Call Number	UA @ lucian @ c:irua:67347			Serial	1059
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	Author	Baelus, B.J.; Yampolskii, S.V.; Peeters, F.M.; Montevecchi, E.; Indekeu, J.O.
	Title	Superconducting properties of mesoscopic cylinders with enhanced surface superconductivity			Type	A1 Journal article
	Year	2002	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	65	Issue	2	Pages	024510-10
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The superconducting state of an infinitely long superconducting cylinder surrounded by a medium which enhances its superconductivity near the boundary is studied within the nonlinear Ginzburg-Landau theory. This enhancement can be due to the proximity of another superconductor or due to surface treatment. Quantities such as the free energy, the magnetization and the Cooper-pair density are calculated. Phase diagrams are obtained to investigate how the critical field and the critical temperature depend on this surface enhancement for different values of the Ginzburg-Landau parameter kappa. Increasing the superconductivity near the surface leads to higher critical fields and critical temperatures. For small cylinder diameters only giant vortex states nucleate, while for larger cylinders multivortices can nucleate. The stability of these multivortex states also depends on the surface enhancement. For type-I superconductors we found the remarkable result that for a range of values of the surface extrapolation length the superconductor can transit from the Meissner state into superconducting states with vorticity L > 1. Such a behavior is not found for the case of large kappa, i.e., type-II superconductivity,
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000173213100099	Publication Date	2002-07-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0163-1829;1095-3795;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	13	Open Access
	Notes				Approved	Most recent IF: 3.836; 2002 IF: NA
	Call Number	UA @ lucian @ c:irua:103890			Serial	3363
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	Author	Xu, W.; Peeters, F.M.; Devreese, J.T.
	Title	Streaming-to-accumulation transition in a 2-dimensional electron-system in a polar semiconductor			Type	A1 Journal article
	Year	1992	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	46	Issue	12	Pages	7571-7580
	Keywords	A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
	Abstract	Hot-electron transport is studied for a two-dimensional electron gas coupled to longitudinal-optical phonons in crossed electric and magnetic fields. At low electric and high magnetic fields the electrons are accumulated, while at high electric fields they are in a streaming state. We develop a streaming-to-accumulation transition model and compare the results with that from a Monte Carlo simulation.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	A1992JQ37800028	Publication Date	2002-07-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0163-1829;1095-3795;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.736	Times cited	13	Open Access
	Notes				Approved	PHYSICS, APPLIED 28/145 Q1 #
	Call Number	UA @ lucian @ c:irua:103023			Serial	3174
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	Author	Wen, X.; Peeters, F.M.; Devreese, J.T.
	Title	Streaming-to-accumulation transition in a two-dimensional electron system in a polar semiconductor			Type	A1 Journal article
	Year	1992	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	46	Issue		Pages	7571-7580
	Keywords	A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	A1992JQ37800028	Publication Date	2002-07-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0163-1829	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.736	Times cited	13	Open Access
	Notes				Approved	PHYSICS, APPLIED 28/145 Q1 #
	Call Number	UA @ lucian @ c:irua:2913			Serial	3175
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	Author	Sabani, D.; Bacaksiz, C.; Milošević, M.V.
	Title	Ab initio methodology for magnetic exchange parameters: Generic four-state energy mapping onto a Heisenberg spin Hamiltonian			Type	A1 Journal article
	Year	2020	Publication	Physical Review B	Abbreviated Journal	Phys Rev B
	Volume	102	Issue	1	Pages	014457-14458
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The recent development in the field of two-dimensional magnetic materials urges reliable theoretical methodology for determination of magnetic properties. Among the available methods, ab initio four-state energy mapping based on density functional theory stands out as a powerful technique to calculate the magnetic exchange interaction in the Heisenberg spin model. Although the required formulas were explained in earlier works, the considered Hamiltonian in those studies always corresponded to the specific case that the off-diagonal part of J matrix is antisymmetric, which may be misleading in other cases. Therefore, using the most general form of the Heisenberg spin Hamiltonian, we here derive the generic formulas. With a proper choice of four different magnetic states, a single formula governs all elements of the exchange interaction matrix for any considered pair of spin sites.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000554409500002	Publication Date	2020-07-31
	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	3.7	Times cited	13	Open Access
	Notes	; This work was supported by the Research Foundation-Flanders (FWO-Vlaanderen) and the Special Research Funds of the University of Antwerp (TOPBOF). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation-Flanders (FWO-Vlaanderen) and the Flemish Government, Department EWI. ;			Approved	Most recent IF: 3.7; 2020 IF: 3.836
	Call Number	UA @ admin @ c:irua:171203			Serial	6448
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	Author	Saberi-Pouya, S.; Conti, S.; Perali, A.; Croxall, A.F.; Hamilton, A.R.; Peeters, F.M.; Neilson, D.
	Title	Experimental conditions for the observation of electron-hole superfluidity in GaAs heterostructures			Type	A1 Journal article
	Year	2020	Publication	Physical Review B	Abbreviated Journal	Phys Rev B
	Volume	101	Issue	14	Pages	140501-140506
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The experimental parameter ranges needed to generate superfluidity in optical and drag experiments in GaAs double quantum wells are determined using a formalism that includes self-consistent screening of the Coulomb pairing interaction in the presence of the superfluid. The very different electron and hole masses in GaAs make this a particularly interesting system for superfluidity with exotic superfluid phases predicted in the BCS-Bose-Einstein condensation crossover regime. We find that the density and temperature ranges for superfluidity cover the range for which optical experiments have observed indications of superfluidity but that existing drag experiments lie outside the superfluid range. We also show that, for samples with low mobility with no macroscopically connected superfluidity, if the superfluidity survives in randomly distributed localized pockets, standard quantum capacitance measurements could detect these pockets.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000523627600001	Publication Date	2020-04-06
	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	3.7	Times cited	13	Open Access
	Notes	; We thank K. Das Gupta, F. Dubin, U. Siciliani de Cumis, M. Pini, and J. Waldie for illuminating discus-sions. This work was partially supported by the Flemish Science Foundation (FWO-Vl) and the Australian Government through the Australian Research Council Centre of Excellence in Future Low-Energy Electronics (Project No. CE170100039). ;			Approved	Most recent IF: 3.7; 2020 IF: 3.836
	Call Number	UA @ admin @ c:irua:168561			Serial	6517
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	Author	Mirzakhani, M.; Peeters, F.M.; Zarenia, M.
	Title	Circular quantum dots in twisted bilayer graphene			Type	A1 Journal article
	Year	2020	Publication	Physical Review B	Abbreviated Journal	Phys Rev B
	Volume	101	Issue	7	Pages	075413
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Within a tight-binding approach, we investigate the effect of twisting angle on the energy levels of circular bilayer graphene (BLG) quantum dots (QDs) in both the absence and presence of a perpendicular magnetic field. The QDs are defined by an infinite-mass potential, so that the specific edge effects are not present. In the absence of magnetic field (or when the magnetic length is larger than the moire length), we show that the low-energy states in twisted BLG QDs are completely affected by the formation of moire patterns, with a strong localization at AA-stacked regions. When magnetic field increases, the energy gap of an untwisted BLG QD closes with the edge states, localized at the boundaries between the AA- and AB-stacked spots in a twisted BLG QD. Our observation of the spatial localization of the electrons in twisted BLG QDs can be experimentally probed by low-bias scanning tunneling microscopy measurements.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000512772200004	Publication Date	2020-02-13
	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	3.7	Times cited	13	Open Access
	Notes	; We gratefully acknowledge discussions with I. Snyman. M.Z. acknowledges support from the U.S. Department of Energy (Office of Science) under Grant No. DE-FG0205ER46203. ;			Approved	Most recent IF: 3.7; 2020 IF: 3.836
	Call Number	UA @ admin @ c:irua:166493			Serial	6470
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	Author	Juchtmans, R.; Guzzinati, G.; Verbeeck, J.
	Title	Extension of Friedel's law to vortex-beam diffraction			Type	A1 Journal article
	Year	2016	Publication	Physical Review A	Abbreviated Journal	Phys Rev A
	Volume	94	Issue	94	Pages	033858
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Friedel's law states that the modulus of the Fourier transform of real functions is centrosymmetric, while the phase is antisymmetric. As a consequence of this, elastic scattering of plane-wave photons or electrons within the first-order Born-approximation, as well as Fraunhofer diffraction on any aperture, is bound to result in centrosymmetric diffraction patterns. Friedel's law, however, does not apply for vortex beams, and centrosymmetry in general is not present in their diffraction patterns. In this work we extend Friedel's law for vortex beams by showing that the diffraction patterns of vortex beams with opposite topological charge, scattered on the same two-dimensional potential, always are centrosymmetric to one another, regardless of the symmetry of the scattering object. We verify our statement by means of numerical simulations and experimental data. Our research provides deeper understanding in vortex-beam diffraction and can be used to design new experiments to measure the topological charge of vortex beams with diffraction gratings or to study general vortex-beam diffraction.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000384374500010	Publication Date	2016-09-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9926	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.925	Times cited	13	Open Access
	Notes	The authors acknowledge support from the FWO (Aspirant Fonds Wetenschappelijk Onderzoek – Vlaanderen) and the EU under the Seventh Framework Program (FP7) under a contract for an Integrated Infrastructure Initiative, Reference No. 312483-ESTEEM2 and ERC Starting Grant No. 278510 VORTEX.; ECASJO_;			Approved	Most recent IF: 2.925
	Call Number	EMAT @ emat @ c:irua:137200UA @ admin @ c:irua:137200			Serial	4314
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	Author	Moldovan, D.; Masir, M.R.; Peeters, F.M.
	Title	Magnetic field dependence of the atomic collapse state in graphene			Type	A1 Journal article
	Year	2018	Publication	2D materials	Abbreviated Journal	2D Mater
	Volume	5	Issue	1	Pages	015017
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	<script type='text/javascript'>document.write(unpmarked('Quantum electrodynamics predicts that heavy atoms (Z \u003E Z(c) approximate to 170) will undergo the process of atomic collapse where electrons sink into the positron continuum and a new family of so-called collapsing states emerges. The relativistic electrons in graphene exhibit the same physics but at a much lower critical charge (Z(c) approximate to 1) which has made it possible to confirm this phenomenon experimentally. However, there exist conflicting predictions on the effect of a magnetic field on atomic collapse. These theoretical predictions are based on the continuum Dirac-Weyl equation, which does not have an exact analytical solution for the interplay of a supercritical Coulomb potential and the magnetic field. Approximative solutions have been proposed, but because the two effects compete on similar energy scales, the theoretical treatment varies depending on the regime which is being considered. These limitations are overcome here by starting from a tight-binding approach and computing exact numerical results. By avoiding special limit cases, we found a smooth evolution between the different regimes. We predict that the atomic collapse effect persists even after the magnetic field is activated and that the critical charge remains unchanged. We show that the atomic collapse regime is characterized: (1) by a series of Landau level anticrossings and (2) by the absence of root B scaling of the Landau levels with regard to magnetic field strength.'));
	Address
	Corporate Author				Thesis
	Publisher	IOP Publishing	Place of Publication	Bristol	Editor
	Language		Wos	000415015000001	Publication Date	2017-10-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2053-1583	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	6.937	Times cited	13	Open Access
	Notes	; We thank Eva Andrei, Jinhai Mao and Yuhang Jiang for insightful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Funding of the Flemish Government. ;			Approved	Most recent IF: 6.937
	Call Number	UA @ lucian @ c:irua:147361UA @ admin @ c:irua:147361			Serial	4884
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	Author	Zhang, Q.-Z.; Wang, W.-Z.; Bogaerts, A.
	Title	Importance of surface charging during plasma streamer propagation in catalyst pores			Type	A1 Journal article
	Year	2018	Publication	Plasma sources science and technology	Abbreviated Journal	Plasma Sources Sci T
	Volume	27	Issue	6	Pages	065009
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Plasma catalysis is gaining increasing interest, but the underlying mechanisms are far from understood. Different catalyst materials will have different chemical effects, but in addition, they might also have different dielectric constants, which will affect surface charging, and thus the plasma behavior. In this work, we demonstrate that surface charging plays an important role in the streamer propagation and discharge enhancement inside catalyst pores, and in the plasma distribution along the dielectric surface, and this role greatly depends on the dielectric constant of the material. For εr50, surface charging causes the plasma to spread along the dielectric surface and inside the pores, leading to deeper plasma streamer penetration, while for εr>50 or for metallic coatings, the discharge is more localized, due to very weak surface charging. In addition, at εr=50, the significant surface charge density near the pore entrance causes a large potential drop at the sharp pore edges, which induces a strong electric field and results in most pronounced plasma enhancement near the pore entrance.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000436845700002	Publication Date	2018-06-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1361-6595	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.302	Times cited	13	Open Access	OpenAccess
	Notes	We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604) and from the TOP-BOF project of the University of Antwerp. This work was carried out in part using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the University of Antwerp.			Approved	Most recent IF: 3.302
	Call Number	PLASMANT @ plasmant @c:irua:152243			Serial	4995
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	Author	Mehta, A.N.; Gauquelin, N.; Nord, M.; Orekhov, A.; Bender, H.; Cerbu, D.; Verbeeck, J.; Vandervorst, W.
	Title	Unravelling stacking order in epitaxial bilayer MX₂ using 4D-STEM with unsupervised learning			Type	A1 Journal article
	Year	2020	Publication	Nanotechnology	Abbreviated Journal	Nanotechnology
	Volume	31	Issue	44	Pages	445702
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Following an extensive investigation of various monolayer transition metal dichalcogenides (MX2), research interest has expanded to include multilayer systems. In bilayer MX2, the stacking order strongly impacts the local band structure as it dictates the local confinement and symmetry. Determination of stacking order in multilayer MX(2)domains usually relies on prior knowledge of in-plane orientations of constituent layers. This is only feasible in case of growth resulting in well-defined triangular domains and not useful in-case of closed layers with hexagonal or irregularly shaped islands. Stacking order can be discerned in the reciprocal space by measuring changes in diffraction peak intensities. Advances in detector technology allow fast acquisition of high-quality four-dimensional datasets which can later be processed to extract useful information such as thickness, orientation, twist and strain. Here, we use 4D scanning transmission electron microscopy combined with multislice diffraction simulations to unravel stacking order in epitaxially grown bilayer MoS2. Machine learning based data segmentation is employed to obtain useful statistics on grain orientation of monolayer and stacking in bilayer MoS2.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000561424400001	Publication Date	2020-07-14
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0957-4484	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.5	Times cited	13	Open Access	OpenAccess
	Notes	; J.V. acknowledges funding from FLAG-ERA JTC2017 project 'Graph-Eye'. N.G. acknowledges funding from GOA project 'Solarpaint' of the University of Antwerp. This project has received funding from the European Union's Horizon 2020 research and innovation programme under Grant Agreement No. 823717-ESTEEM3. 4D STEM data was acquired on a hybrid pixel detector funded with a Hercules fund 'Direct electron detector for soft matter TEM' from the Flemish Government. M. N. acknowledges funding from a Marie Curie Fellowship agreement No 838001. We thank Dr Jiongjiong Mo and Dr Benjamin Groven for developing the CVD-MoS<INF>2</INF> growth on sapphire and providing the material used in this article. ;			Approved	Most recent IF: 3.5; 2020 IF: 3.44
	Call Number	UA @ admin @ c:irua:171119			Serial	6649
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	Author	Heyne, M.H.; de Marneffe, J.-F.; Delabie, A.; Caymax, M.; Neyts, E.C.; Radu, I.; Huyghebaert, C.; De Gendt, S.
	Title	Two-dimensional WS2 nanoribbon deposition by conversion of pre-patterned amorphous silicon			Type	A1 Journal article
	Year	2017	Publication	Nanotechnology	Abbreviated Journal	Nanotechnology
	Volume	28	Issue	28	Pages	04LT01
	Keywords	A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	We present a method for area selective deposition of 2D WS2 nanoribbons with tunable thickness on a dielectric substrate. The process is based on a complete conversion of a prepatterned, H-terminated Si layer to metallic W by WF6, followed by in situ sulfidation by H2S. The reaction process, performed at 450 degrees C, yields nanoribbons with lateral dimension down to 20 nm and with random basal plane orientation. The thickness of the nanoribbons is accurately controlled by the thickness of the pre-deposited Si layer. Upon rapid thermal annealing at 900 degrees C under inert gas, the WS2 basal planes align parallel to the substrate.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Bristol	Editor
	Language		Wos	000391445100001	Publication Date	2016-12-15
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0957-4484	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.44	Times cited	13	Open Access	OpenAccess
	Notes				Approved	Most recent IF: 3.44
	Call Number	UA @ lucian @ c:irua:140382			Serial	4471
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