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Author Bacaksiz, C.; Fyta, M.
Title Phthalocyanine adsorbed on monolayer CrI₃ : tailoring their magnetic properties Type A1 Journal article
Year 2024 Publication ACS Omega Abbreviated Journal
Volume 9 Issue 32 Pages 34589-34596
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Metallo-phthalocyanines molecules, especially ironphthalocyanines (Fe-Pc), are often examined due to their rich chemical, magnetic, and optoelectronic features. Due to these, Fe-Pc molecules are promising for applications in gas sensors, field-effect transistors, organic LEDs, and data storage. Motivated by this potential, this study investigates Fe-Pc molecules adsorbed on a magnetic monolayer, CrI3. Using quantum-mechanical simulations, the aim of this work was to find pathways to selectively tune and engineer the magnetic and electronic properties of the molecules when they form hybrid complexes. The results quantitatively underline how adsorption alters the magnetic properties of the Fe-Pc molecules. Interestingly, the analysis points to changes in the molecular magnetic anisotropy when comparing the magnetic moment of the isolated molecule to that of the molecule/monolayer complex formed after adsorption. The presence of iodine vacancies was shown to enhance the magnetic interactions between the iron of the Fe-Pc molecule and the chromium of the monolayer. Our findings suggest ways to control oxygen capture-release properties through material choice and defect creation. Insights into the stability and charge density depletion on the molecule provide critical information for selective tuning of the magnetic properties and engineering of the functionalities of these molecule/material complexes.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001280 Publication Date 2024-07-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-1343 ISBN Additional Links UA library record; WoS full record
Impact Factor 4.1 Times cited Open Access (up)
Notes Approved Most recent IF: 4.1; 2024 IF: NA
Call Number UA @ admin @ c:irua:207512 Serial 9310
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Author Yari, S.; Bird, L.; Rahimisheikh, S.; Reis, A.C.; Mohammad, M.; Hadermann, J.; Robinson, J.; Shearing, P.R.; Safari, M.
Title Probing charge transport and microstructural attributes in solvent- versus water-based electrodes with a spotlight on Li-S battery cathode Type A1 Journal article
Year 2024 Publication Advanced energy materials Abbreviated Journal
Volume Issue Pages 2402163
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract In the quest for environmentally benign battery technologies, this study examines the microstructural and transport properties of water-processed electrodes and compares them to conventionally formulated electrodes using the toxic solvent, N-Methyl-2-pyrrolidone (NMP). Special focus is placed on sulfur electrodes utilized in lithium-sulfur batteries for their sustainability and compatibility with diverse binder/solvent systems. The characterization of the electrodes by X-ray micro-computed tomography reveals that in polyvinylidene fluoride (PVDF) Lithium bis(trifluoromethanesulfonyl)imide/NMP, sulfur particles tend to remain in large clusters but break down into finer particles in carboxymethyl cellulose-styrene butadiene rubber (CMC-SBR)/water and lithium polyacrylate (LiPAA)/water dispersions. The findings reveal that in the water-based electrodes, the binder properties dictate the spatial arrangement of carbon particles, resulting in either thick aggregates with short-range connectivity or thin films with long-range connectivity among sulfur particles. Additionally, cracking is found to be particularly prominent in thicker water-based electrodes, propagating especially in regions with larger particle agglomerates and often extending to cause local delamination of the electrodes. These microstructural details are shown to significantly impact the tortuosity and contact resistance of the sulfur electrodes and thereby affecting the cycling performance of the Li-S battery cells. The choice of solvent and binder is crucial in determining particle surface charge, which directly influences active material dispersion and carbon-binder arrangement within the battery porous electrodes. This, in turn, affects ionic and electronic transport properties, ultimately impacting electrochemical performance. Meticulous engineering of the slurry to control these factors is essential for efficient and sustainable water-based electrode processing. image
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001291 Publication Date 2024-08-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1614-6832; 1614-6840 ISBN Additional Links UA library record; WoS full record
Impact Factor 27.8 Times cited Open Access (up)
Notes Approved Most recent IF: 27.8; 2024 IF: 16.721
Call Number UA @ admin @ c:irua:207624 Serial 9311
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Author Vermeulen, B.B.; Sorée, B.; Couet, S.; Temst, K.; Van Nguyen, D.
Title Progress in spin logic devices based on domain-wall motion Type A1 Journal article
Year 2024 Publication Micromachines Abbreviated Journal
Volume 15 Issue 6 Pages 696-20
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Spintronics, utilizing both the charge and spin of electrons, benefits from the nonvolatility, low switching energy, and collective behavior of magnetization. These properties allow the development of magnetoresistive random access memories, with magnetic tunnel junctions (MTJs) playing a central role. Various spin logic concepts are also extensively explored. Among these, spin logic devices based on the motion of magnetic domain walls (DWs) enable the implementation of compact and energy-efficient logic circuits. In these devices, DW motion within a magnetic track enables spin information processing, while MTJs at the input and output serve as electrical writing and reading elements. DW logic holds promise for simplifying logic circuit complexity by performing multiple functions within a single device. Nevertheless, the demonstration of DW logic circuits with electrical writing and reading at the nanoscale is still needed to unveil their practical application potential. In this review, we discuss material advancements for high-speed DW motion, progress in DW logic devices, groundbreaking demonstrations of current-driven DW logic, and its potential for practical applications. Additionally, we discuss alternative approaches for current-free information propagation, along with challenges and prospects for the development of DW logic.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001256 Publication Date 2024-05-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2072-666x ISBN Additional Links UA library record; WoS full record; WoS full record
Impact Factor Times cited Open Access (up)
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:207054 Serial 9312
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Author Ghosh, S.; Pradhan, B.; Bandyopadhyay, A.; Skvortsova, I.; Zhang, Y.; Sternemann, C.; Paulus, M.; Bals, S.; Hofkens, J.; Karki, K.J.; Materny, A.
Title Rashba-type band splitting effect in 2D (PEA)₂PbI₄ perovskites and its impact on exciton-phonon coupling Type A1 Journal article
Year 2024 Publication The journal of physical chemistry letters Abbreviated Journal
Volume 15 Issue 31 Pages 7970-7978
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Despite a few recent reports on Rashba effects in two-dimensional (2D) Ruddlesden-Popper (RP) hybrid perovskites, the precise role of organic spacer cations in influencing Rashba band splitting remains unclear. Here, using a combination of temperature-dependent two-photon photoluminescence (2PPL) and time-resolved photoluminescence spectroscopy, alongside density functional theory (DFT) calculations, we contribute to significant insights into the Rashba band splitting found for 2D RP hybrid perovskites. The results demonstrate that the polarity of the organic spacer cation is crucial in inducing structural distortions that lead to Rashba-type band splitting. Our investigations show that the intricate details of the Rashba band splitting occur for organic cations with low polarity but not for more polar ones. Furthermore, we have observed stronger exciton-phonon interactions due to the Rashba-type band splitting effect. These findings clarify the importance of selecting appropriate organic spacer cations to manipulate the electronic properties of 2D perovskites.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001280 Publication Date 2024-07-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1948-7185 ISBN Additional Links UA library record; WoS full record
Impact Factor 5.7 Times cited Open Access (up)
Notes Approved Most recent IF: 5.7; 2024 IF: 9.353
Call Number UA @ admin @ c:irua:207672 Serial 9313
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Author Barich, H.; Voet, O.; Sleegers, N.; Schram, J.; Montiel, F.N.; Beltran, V.; Nuyts, G.; De Wael, K.
Title Selecting optimal carbon inks for fabricating high-performance screen-printed electrodes for diverse electroanalytical applications Type A1 Journal article
Year 2024 Publication Journal of electroanalytical chemistry : an international journal devoted to all aspects of electrode kynetics, interfacial structure, properties of electrolytes, colloid and biological electrochemistry. Abbreviated Journal
Volume 971 Issue Pages 118585-11
Keywords A1 Journal article; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab); Antwerp engineering, PhotoElectroChemistry & Sensing (A-PECS)
Abstract Carbon-based screen-printed electrodes (SPEs) are extensively employed in electrochemistry due to their reproducibility, low-cost production, disposability and versatility. It is commonly accepted that batch to batch variations may occur due to variations in the ink formulation or the use of a different ink to print the electrodes. In this paper, three different commercial carbon-based inks (DuPont, Loctite and SunChemical) were used to manufacture SPEs, referred to respectively as Dup-SPE, Loc-SPE and Sun-SPE, using a semi-automated screen-printing technology. This study focuses on evaluating the quality, characteristics and electrochemical performance of the fabricated SPEs. Furthermore, the study aimed to investigate potential correlations between the ink composition and the nature of different target molecules, as well as their electroanalytical responses. Specifically, phenolic compounds and cocaine cutting agents are tested in alkaline conditions, while benzodiazepines and cephalosporine antibiotics are investigated in acidic media using square wave voltammetry (SWV). This aims to extract insights for the proper selection of inks and SPEs in both conditions. Additionally, a scan rate study of cephalosporine antibiotics using linear sweep voltammetry (LSV) is performed confirming the ion-exchange polymer layer on the electrode surface of Loc-SPE, which impact surface and electrochemical properties, leading to drawbacks in alkaline SWV sensing, but strategic benefits in reductive sensing resulting in an enhanced selective detection of specific targets. The insights on ink-specific influences on the surface and electrochemical properties of the SPEs obtained, may be useful for facilitating the electrode selection in diverse electrochemical applications, emphasizing the critical role of ink composition in achieving desired sensing capabilities.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2024-08-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1572-6657; 1873-2569 ISBN Additional Links UA library record
Impact Factor 4.5 Times cited Open Access (up)
Notes Approved Most recent IF: 4.5; 2024 IF: 3.012
Call Number UA @ admin @ c:irua:207447 Serial 9314
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Author Kadu, A.; Lucka, F.; Batenburg, K.J.
Title Single-shot tomography of discrete dynamic objects Type A1 Journal article
Year 2024 Publication IEEE transactions on computational imaging Abbreviated Journal
Volume 10 Issue Pages 941-952
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract This paper presents a novel method for the reconstruction of high-resolution temporal images in dynamic tomographic imaging, particularly for discrete objects with smooth boundaries that vary over time. Addressing the challenge of limited measurements per time point, we propose a technique that incorporates spatial and temporal information of the dynamic objects. Our method uses the explicit assumption of homogeneous attenuation values of discrete objects. We achieve this computationally through the application of the level-set method for image segmentation and the representation of motion via a sinusoidal basis. The result is a computationally efficient and easily optimizable variational framework that enables the reconstruction of high-quality 2D or 3D image sequences with a single projection per frame. Compared to variational regularization-based methods using similar image models, our approach demonstrates superior performance on both synthetic and pseudo-dynamic real X-ray tomography datasets. The implications of this research extend to improved visualization and analysis of dynamic processes in tomographic imaging, finding potential applications in diverse scientific and industrial domains. The supporting data and code are provided.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001256 Publication Date 2024-06-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2573-0436; 2333-9403 ISBN Additional Links UA library record; WoS full record; WoS full record
Impact Factor 5.4 Times cited Open Access (up)
Notes Approved Most recent IF: 5.4; 2024 IF: NA
Call Number UA @ admin @ c:irua:207017 Serial 9315
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Author Thomen, D.M.N.; Sevik, C.; Milošević, M.V.; Teles, L.K.; Chaves, A.
Title Strain and stacking registry effects on the hyperbolicity of exciton polaritons in few-layer black phosphorus Type A1 Journal article
Year 2024 Publication Physical review B Abbreviated Journal
Volume 109 Issue 24 Pages 245413-245419
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We analyze, from first -principles calculations, the excitonic properties of monolayer black phosphorus (BP) under strain, as well as of bilayer BP with different stacking registries, as a base platform for the observation and use of hyperbolic polaritons. In the unstrained case, our results confirm the in -plane hyperbolic behavior of polaritons coupled to the ground -state excitons in both mono- and bilayer systems, as observed in recent experiments. With strain, we reveal that the exciton-polariton hyperbolicity in monolayer BP is enhanced (reduced) by compressive (tensile) strain in the zig-zag direction of the crystal. In the bilayer case, different stacking registries are shown to exhibit hyperbolic exciton polaritons with different dispersion, while also peaking at different frequencies. This renders both mechanical stress and stacking registry control as practical tools for tuning physical properties of hyperbolic exciton polaritons in black phosphorus, which facilitates detection and further optoelectronic use of these quasiparticles.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001247621000008 Publication Date 2024-06-10
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
Impact Factor 3.7 Times cited Open Access (up)
Notes Approved Most recent IF: 3.7; 2024 IF: 3.836
Call Number UA @ admin @ c:irua:206631 Serial 9316
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Author Gonzalez-Garcia, A.; Bacaksiz, C.; Frauenheim, T.; Milošević, M.V.
Title Strong spin-lattice coupling and high-temperature magnetic ordering in monolayer chromium dichalcogenides Type A1 Journal article
Year 2024 Publication Physical review materials Abbreviated Journal
Volume 8 Issue 6 Pages 064001-64009
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We detail the magnetic properties of monolayer CrX2 and its Janus counterparts CrXY (X, Y = S, Se, Te, with X not equal Y) using ab initio methods and Landau-Lifshitz-Gilbert magnetization dynamics, and uncover the pronouncedly strong interplay between their structure symmetry and the magnetic order. The relaxation of nonmagnetic chalcogen atoms, that carry large spin-orbit coupling, changes the energetically preferential magnetic order between in-plane antiferromagnetic and tilted ferromagnetic one. The considered Janus monolayers exhibit sizable Dzyaloshinskii-Moriya interaction, in some cases above 20% of the isotropic exchange, and critical temperature of the long-range magnetic order in the vicinity or even significantly above the room temperature.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001247462600001 Publication Date 2024-06-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record
Impact Factor 3.4 Times cited Open Access (up)
Notes Approved Most recent IF: 3.4; 2024 IF: NA
Call Number UA @ admin @ c:irua:206660 Serial 9317
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Author Mazurkow, J.M.; Montiel, F.N.; Van Echelpoel, R.; Kusior, A.; De Wael, K.
Title The potential of electrochemical sensors to unveil counterfeits : Xanax as a case study Type A1 Journal article
Year 2024 Publication Electrochimica acta Abbreviated Journal
Volume 494 Issue Pages 144458-8
Keywords A1 Journal article; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab); Antwerp engineering, PhotoElectroChemistry & Sensing (A-PECS)
Abstract The illicit drug market has been constantly evolving in the last decades, with a significant rise in counterfeit medicines posing serious public health risks. Benzodiazepines (BZDs) such as alprazolam (generally sold under the brand name Xanax), have particularly become the target of counterfeiting efforts due to their addictive nature and upsurge of unregulated designer BZDs. These counterfeit versions frequently resemble legitimate products but contain harmful adulterants or other potent illicit substances. Few methods have been developed to tackle counterfeit pills, usually limited to accurate and sophisticated laboratory equipment. This study explores the feasibility of combining electrochemical fingerprinting with data analysis to overcome the limitations of traditional methods. First, the electrochemical behavior of selected BZDs is studied, and analytical parameters such as pH are optimized. Then, the electroanalysis of common adulterants and illicit drugs is addressed and integrated into a user-friendly app, including a flowchart system. The proposed electrochemical strategy enables the detection of counterfeit Xanax by identifying the presence or absence of alprazolam. It also allows determination of the alprazolam content within a pill while meeting the fundamental requirements of the end users. This study represents an on-site methodology to address the growing challenges posed by BZDs, easily transferable to counterfeit medicines from other drug groups.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001244860300001 Publication Date 2024-05-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4686 ISBN Additional Links UA library record; WoS full record
Impact Factor 6.6 Times cited Open Access (up)
Notes Approved Most recent IF: 6.6; 2024 IF: 4.798
Call Number UA @ admin @ c:irua:206519 Serial 9321
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Author Kirkpatrick, S.; Sanyova, J.; Janssens, K.; van der Snickt, G.
Title The synergistic influence of metal cations on the drying and viscosity of linseed oil assessed by means of model samples containing synthesised metal carboxylates Type A1 Journal article
Year 2024 Publication Heritage science Abbreviated Journal
Volume 12 Issue 1 Pages 209-215
Keywords A1 Journal article; Art; Antwerp Cultural Heritage Sciences (ARCHES); Antwerp X-ray Imaging and Spectroscopy (AXIS)
Abstract The recent multi-analytical study carried out on the Van Eyck's Ghent Altarpiece showed the simultaneous presence of several kinds of metal carboxylates in oil-rich glaze layers. This outcome raised the question whether these carboxylates had already formed during the preparation of the oil binder by the artists. In the case of early-stage formation, they may have had an impact on the drying rate of the resulting oil, as well as on its handling properties. This hypothesis was investigated using a model system of in-house-prepared linseed oil containing incremental concentrations (2-5-10 wt.%) of relevant metal carboxylates (i.e. Ca-, Zn-, Cu-, and Pb oleates and stearates). This paper describes the influence of these type of molecules on the drying rate of linseed oil and, to an extent, on its viscosity. The drying time of the linseed oil, to which one or more metal carboxylates were added, was measured with a drying recorder while the viscosity was assessed with a rheometer. When introduced together, some of these metal carboxylates act in synergy to shorten the drying time with respect to the situation when the same metal carboxylates were added separately to linseed oil. Mixtures of Ca- and Zn-oleates proved to have a larger effect than other binary combinations. Addition of two metal oleates (combination of Ca/Zn/Cu/Pb) reduced the drying time even more. On the other hand, specific combinations of three metal stearates and/or oleates also demonstrated a significant synergistic effect towards increasing the viscosity of the binder. Especially combinations of Ca/Zn/Cu and Ca/Zn/Pb stearates and oleates gave rise to the highest level of linseed oil viscosity increase, when compared to the situation in which the same metal carboxylates were added separately.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001249638200003 Publication Date 2024-06-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7445 ISBN Additional Links UA library record; WoS full record
Impact Factor 2.5 Times cited Open Access (up)
Notes Approved Most recent IF: 2.5; 2024 IF: NA
Call Number UA @ admin @ c:irua:206484 Serial 9322
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Author Hoekx, S.; Daems, N.; Arenas Esteban, D.; Bals, S.; Breugelmans, T.
Title Toward the rational design of Cu electrocatalysts for improved performance of the NO3RR Type A1 Journal article
Year 2024 Publication ACS applied energy materials Abbreviated Journal
Volume 7 Issue 9 Pages 3761-3775
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT)
Abstract Cu is one of the most promising materials as an electrocatalyst for the nitrate reduction reaction (NO3RR) to ammonia, a reaction that can simultaneously remove nitrates from wastewater and produce ammonia, a high-value commodity chemical. However, a rational approach to catalyst design is lacking, limiting efficient catalyst optimization. In this work, we propose a way to synthesize monodisperse, polycrystalline Cu NPs with small variances in size by changing the carbon chain length of the phosphonic acid-based ligand. Cu NPs with 8.3, 10.0, and 11.9 nm diameters are successfully synthesized, and high-resolution electron microscopy and tomography are used to characterize these NPs in depth. By isolating Cu NP size as a parameter, we can unequivocally establish its effect on electrochemical performance for the NO3RR to ammonia under optimal operating conditions for the catalyst (0.1 M KOH electrolyte at -1.25 V vs RHE, as established in the first phase). The smallest Cu NPs (8.3 nm with a TDPA ligand) perform best, achieving Faradaic efficiencies (FEs) of 85.4% and absolute current densities of similar to 250 mA cm(-2), with increasing current densities and constant FEs as the particle size decreases. To allow for a rational approach to Cu-based catalyst design from a stability perspective, this work completed a first study of the main degradation pathway that the Cu NPs undergo during NO3RR. High-resolution electron microscopy and tomography are used to characterize the particles at various stages of the reaction. The NPs undergo agglomeration, pulverization, and particle detachment due to the reaction, starting at a particle size of 8.3 nm and progressively getting smaller, but leveling off, until a NP size of 2.6 nm is reached after 2 h of electrolysis. This decrease in NP size goes paired with a decrease in FE from 83% after the first 15 min to 74% after 2 h at -0.75 V vs RHE, despite the increase in active surface area. These insights into the most prominent degradation mechanisms allow for rational adjustments to future catalysts to combat these changes; for example, by embedding NPs in a tailored support, morphological degradation could be impeded. Therefore, these insights allow for a rational approach to the improvement of the stability of Cu-based catalysts for the NO3RR, a very important but often an overlooked aspect of catalyst design.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001228056800001 Publication Date 2024-04-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2574-0962 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.4 Times cited Open Access (up)
Notes Approved Most recent IF: 6.4; 2024 IF: NA
Call Number UA @ admin @ c:irua:206469 Serial 9323
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Author Shafiei, M.; Fazileh, F.; Peeters, F.M.; Milošević, M.V.
Title Tuning the quantum phase transition of an ultrathin magnetic topological insulator Type A1 Journal article
Year 2024 Publication Physical review materials Abbreviated Journal
Volume 8 Issue 7 Pages 074201-74208
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We explore the effect of thickness, magnetization direction, strain, and gating on the topological quantum phase transition of a thin-film magnetic topological insulator. Reducing the film thickness to the ultrathin regime couples the edge states on the two surfaces, opening a gap known as the hybridization gap, and causing a phase transition from a topological insulator to a normal insulator (NI). An out-of-plane/in-plane magnetization of size proportional to the hybridization gap triggers a phase transition from a normal insulator state to a quantum anomalous Hall (QAH)/semimetal state. A magnetization tilt by angle 0 from the out-of-plane axis influences the topological phase transition in a way that for sufficiently large 0, no phase transition from NI to QAH can be observed regardless of the sample thickness or magnetization, and for 0 close to pi /2 the system transits to a semimetal phase. Furthermore, we demonstrate that compressive/tensile strain can be used to decrease/increase the magnetization threshold for the topological phase transition. Finally, we reveal the effect of a vertical potential acting on the film, be it due to the substrate or applied gating, which breaks inversion symmetry and raises the magnetization threshold for the transition from NI to QAH state.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001281 Publication Date 2024-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record
Impact Factor 3.4 Times cited Open Access (up)
Notes Approved Most recent IF: 3.4; 2024 IF: NA
Call Number UA @ admin @ c:irua:207598 Serial 9324
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Author Lavor, I.R.; Tao, Z.H.; Dong, H.M.; Chaves, A.; Peeters, F.M.; Milošević, M.V.
Title Ultrasensitive acoustic graphene plasmons in a graphene-transition metal dichalcogenide heterostructure : strong plasmon-phonon coupling and wavelength sensitivity enhanced by a metal screen Type A1 Journal article
Year 2024 Publication Carbon Abbreviated Journal
Volume 228 Issue Pages 119401-119409
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Acoustic plasmons in graphene exhibit strong confinement induced by a proximate metal surface and hybridize with phonons of transition metal dichalcogenides (TMDs) when these materials are combined in a van der Waals heterostructure, thus forming screened graphene plasmon-phonon polaritons (SGPPPs), a type of acoustic mode. While SGPPPs are shown to be very sensitive to the dielectric properties of the environment, enhancing the SGPPPs coupling strength in realistic heterostructures is still challenging. Here we employ the quantum electrostatic heterostructure model, which builds upon the density functional theory calculations for monolayers, to show that the use of a metal as a substrate for graphene-TMD heterostructures (i) vigorously enhances the coupling strength between acoustic plasmons and the TMD phonons, and (ii) markedly improves the sensitivity of the plasmon wavelength on the structural details of the host platform in real space, thus allowing one to use the effect of environmental screening on acoustic plasmons to probe the structure and composition of a van der Waals heterostructure down to the monolayer resolution.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001267 Publication Date 2024-07-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record; WoS full record
Impact Factor 10.9 Times cited Open Access (up)
Notes Approved Most recent IF: 10.9; 2024 IF: 6.337
Call Number UA @ admin @ c:irua:207077 Serial 9325
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Author Zhang, Y.; Grunewald, L.; Cao, X.; Abdelbarey, D.; Zheng, X.; Rugeramigabo, E.P.; Verbeeck, J.; Zopf, M.; Ding, F.
Title Unveiling the 3D morphology of epitaxial GaAs/AlGaAs quantum dots Type A1 Journal article
Year 2024 Publication Nano letters Abbreviated Journal
Volume 24 Issue 33 Pages 10106-10113
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Strain-free GaAs/AlGaAs semiconductor quantum dots (QDs) grown by droplet etching and nanohole infilling (DENI) are highly promising candidates for the on-demand generation of indistinguishable and entangled photon sources. The spectroscopic fingerprint and quantum optical properties of QDs are significantly influenced by their morphology. The effects of nanohole geometry and infilled material on the exciton binding energies and fine structure splitting are well-understood. However, a comprehensive understanding of GaAs/AlGaAs QD morphology remains elusive. To address this, we employ high-resolution scanning transmission electron microscopy (STEM) and reverse engineering through selective chemical etching and atomic force microscopy (AFM). Cross-sectional STEM of uncapped QDs reveals an inverted conical nanohole with Al-rich sidewalls and defect-free interfaces. Subsequent selective chemical etching and AFM measurements further reveal asymmetries in element distribution. This study enhances the understanding of DENI QD morphology and provides a fundamental three-dimensional structural model for simulating and optimizing their optoelectronic properties.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001280 Publication Date 2024-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1530-6984 ISBN Additional Links UA library record; WoS full record
Impact Factor 10.8 Times cited Open Access (up)
Notes Approved Most recent IF: 10.8; 2024 IF: 12.712
Call Number UA @ admin @ c:irua:207525 Serial 9326
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Author Cadorim, L.R.; Sardella, E.; Milošević, M.V.
Title Vortical versus skyrmionic states in the topological phase of a twisted bilayer with d-wave superconducting pairing Type A1 Journal article
Year 2024 Publication Physical review B Abbreviated Journal
Volume 110 Issue 6 Pages 064508-64511
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract It was recently shown that a chiral topological phase emerges from the coupling of two twisted monolayers of superconducting Bi2Sr2CaCu2O8+delta for 2 Sr 2 CaCu 2 O 8 +delta for certain twist angles. In this work, we reveal the behavior of such twisted superconducting bilayers with d x 2 – y 2 pairing symmetry in the presence of an applied magnetic field. Specifically, we show that the emergent vortex matter can serve as a smoking gun for the detection of topological superconductivity in such bilayers. Moreover, we report two distinct skyrmionic states that characterize the chiral topological phase and provide a full account of their experimental signatures and their evolution with the twist angle.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=brocade2&SrcAuth=WosAPI&KeyUT=WOS:001290 Publication Date 2024-08-12
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
Impact Factor 3.7 Times cited Open Access (up)
Notes Approved Most recent IF: 3.7; 2024 IF: 3.836
Call Number UA @ admin @ c:irua:208602 Serial 9327
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Author Vávra, O.; Gaži, S.; Golubović, D.S.; Vávra, I.; Dérer, J.; Verbeeck, J.; Van Tendeloo, G.; Moshchalkov, V.V.
Title 0 and π phase Josephson coupling through an insulating barrier with magnetic impurities Type A1 Journal article
Year 2006 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 74 Issue 2 Pages 020502
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We have studied the temperature and field dependencies of the critical current I(C) in the Nb-Fe(0.1)Si(0.9)-Nb Josephson junction with a tunneling barrier formed by a paramagnetic insulator. We demonstrate that in these junctions coexistence of both the 0 and the pi states within one tunnel junction occurs, and leads to the appearance of a sharp cusp in the temperature dependence I(C)(T), similar to the I(C)(T) cusp found for the 0-pi transition in metallic pi junctions. This cusp is not related to the 0-pi temperature-induced transition itself, but is caused by the different temperature dependencies of the opposing 0 and pi supercurrents through the barrier.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000239426600010 Publication Date 2006-07-15
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 27 Open Access (up)
Notes Approved Most recent IF: 3.836; 2006 IF: 3.107
Call Number UA @ lucian @ c:irua:60087 c:irua:60087 c:irua:60087 c:irua:60087UA @ admin @ c:irua:60087 Serial 1
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Author Van Tendeloo, G.; Bals, S.; Van Aert, S.; Verbeeck, J.; van Dyck, D.
Title Advanced electron microscopy for advanced materials Type A1 Journal article
Year 2012 Publication Advanced materials Abbreviated Journal Adv Mater
Volume 24 Issue 42 Pages 5655-5675
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Vision lab
Abstract The idea of this Review is to introduce newly developed possibilities of advanced electron microscopy to the materials science community. Over the last decade, electron microscopy has evolved into a full analytical tool, able to provide atomic scale information on the position, nature, and even the valency atoms. This information is classically obtained in two dimensions (2D), but can now also be obtained in 3D. We show examples of applications in the field of nanoparticles and interfaces.
Address
Corporate Author Thesis
Publisher Place of Publication Weinheim Editor
Language Wos 000310602200001 Publication Date 2012-08-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0935-9648; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 19.791 Times cited 107 Open Access (up)
Notes This work was supported by funding from the European Research Council under the 7th Framework Program (FP7), ERC grant No 246791 – COUNTATOMS. J.V. Acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. The authors gratefully acknowledge funding from the Research Foundation Flanders (FWO, Belgium). The Qu-Ant-EM microscope was partly funded by the Hercules Fund from the Flemish Government. We thank Rafal Dunin-Borkowski for providing Figure 5d. The authors would like to thank the colleagues who have contributed to this work over the years, including K.J. Batenburg, R. Erni, B. Goris, F. Leroux, H. Lichte, A. Lubk, B. Partoens, M. D. Rossell, P. Schattschneider, B. Schoeters, D. Schryvers, H. Tan, H. Tian, S. Turner, M. van Huis. ECASJO_; Approved Most recent IF: 19.791; 2012 IF: 14.829
Call Number UA @ lucian @ c:irua:100470UA @ admin @ c:irua:100470 Serial 70
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Author Iyikanat, F.; Sahin, H.; Senger, R.T.; Peeters, F.M.
Title Ag and Au atoms intercalated in bilayer heterostructures of transition metal dichalcogenides and graphene Type A1 Journal article
Year 2014 Publication APL materials Abbreviated Journal Apl Mater
Volume 2 Issue 9 Pages 092801
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The diffusive motion of metal nanoparticles Au and Ag on monolayer and between bilayer heterostructures of transition metal dichalcogenides and graphene are investigated in the framework of density functional theory. We found that the minimum energy barriers for diffusion and the possibility of cluster formation depend strongly on both the type of nanoparticle and the type of monolayers and bilayers. Moreover, the tendency to form clusters of Ag and Au can be tuned by creating various bilayers. Tunability of the diffusion characteristics of adatoms in van der Waals heterostructures holds promise for controllable growth of nanostructures. (C) 2014 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000342568000020 Publication Date 2014-08-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2166-532X ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.335 Times cited 10 Open Access (up)
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus Marie Curie Fellowship. F.I. and R.T.S. acknowledge the support from TUBITAK Project No. 111T318. ; Approved Most recent IF: 4.335; 2014 IF: NA
Call Number UA @ lucian @ c:irua:119950 Serial 82
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Author Wang, A.; Turner, S.; Van Aert, S.; van Dyck, D.
Title An alternative approach to determine attainable resolution directly from HREM images Type A1 Journal article
Year 2013 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 133 Issue Pages 50-61
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract The concept of resolution in high-resolution electron microscopy (HREM) is the power to resolve neighboring atoms. Since the resolution is related to the width of the point spread function of the microscope, it could in principle be determined from the image of a point object. However, in electron microscopy there are no ideal point objects. The smallest object is an individual atom. If the width of an atom is much smaller than the resolution of the microscope, this atom can still be considered as a point object. As the resolution of the microscope enters the sub-Å regime, information about the microscope is strongly entangled with the information about the atoms in HREM images. Therefore, we need to find an alternative method to determine the resolution in an object-independent way. In this work we propose to use the image wave of a crystalline object in zone axis orientation. Under this condition, the atoms of a column act as small lenses so that the electron beam channels through the atom column periodically. Because of this focusing, the image wave of the column can be much more peaked than the constituting atoms and can thus be a much more sensitive probe to measure the resolution. Our approach is to use the peakiness of the image wave of the atom column to determine the resolution. We will show that the resolution can be directly linked to the total curvature of the atom column wave. Moreover, we can then directly obtain the resolution of the microscope given that the contribution from the object is known, which is related to the bounding energy of the atom. The method is applied on an experimental CaTiO3 image wave.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000324471800007 Publication Date 2013-05-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0304-3991; ISBN Additional Links UA library record; WoS full record
Impact Factor 2.843 Times cited Open Access (up)
Notes FWO; Hercules; Esteem2; esteem2_jra2 Approved Most recent IF: 2.843; 2013 IF: 2.745
Call Number UA @ lucian @ c:irua:109919 Serial 90
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Author Ludu, A.; Van Deun, J.; Milošević, M.V.; Cuyt, A.; Peeters, F.M.
Title Analytic treatment of vortex states in cylindrical superconductors in applied axial magnetic field Type A1 Journal article
Year 2010 Publication Journal of mathematical physics Abbreviated Journal J Math Phys
Volume 51 Issue 8 Pages 082903,1-082903,29
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We solve the linear GinzburgLandau (GL) equation in the presence of a uniform magnetic field with cylindrical symmetry and we find analytic expressions for the eigenfunctions in terms of the confluent hypergeometric functions. The discrete spectrum results from an implicit equation associated to the boundary conditions and it is resolved in analytic form using the continued fractions formalism. We study the dependence of the spectrum and the eigenfunctions on the sample size and the surface conditions for solid and hollow cylindrical superconductors. Finally, the solutions of the nonlinear GL formalism are constructed as expansions in the linear GL eigenfunction basis and selected by minimization of the free energy. We present examples of vortex states and their energies for different samples in enhancing/suppressing superconductivity surroundings.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000281905000026 Publication Date 2010-08-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2488; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.077 Times cited 10 Open Access (up)
Notes ; ; Approved Most recent IF: 1.077; 2010 IF: 1.291
Call Number UA @ lucian @ c:irua:84880 Serial 106
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Author de Backer, A.; Martinez, G.T.; Rosenauer, A.; Van Aert, S.
Title Atom counting in HAADF STEM using a statistical model-based approach : methodology, possibilities, and inherent limitations Type A1 Journal article
Year 2013 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 134 Issue Pages 23-33
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract In the present paper, a statistical model-based method to count the number of atoms of monotype crystalline nanostructures from high resolution high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM) images is discussed in detail together with a thorough study on the possibilities and inherent limitations. In order to count the number of atoms, it is assumed that the total scattered intensity scales with the number of atoms per atom column. These intensities are quantitatively determined using model-based statistical parameter estimation theory. The distribution describing the probability that intensity values are generated by atomic columns containing a specific number of atoms is inferred on the basis of the experimental scattered intensities. Finally, the number of atoms per atom column is quantified using this estimated probability distribution. The number of atom columns available in the observed STEM image, the number of components in the estimated probability distribution, the width of the components of the probability distribution, and the typical shape of a criterion to assess the number of components in the probability distribution directly affect the accuracy and precision with which the number of atoms in a particular atom column can be estimated. It is shown that single atom sensitivity is feasible taking the latter aspects into consideration.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000324474900005 Publication Date 2013-05-17
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 48 Open Access (up)
Notes FWO; Esteem2; FP 2007-2013; esteem2_jra2 Approved Most recent IF: 2.843; 2013 IF: 2.745
Call Number UA @ lucian @ c:irua:109916 Serial 162
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Author Mueller, K.; Krause, F.F.; Béché, A.; Schowalter, M.; Galioit, V.; Loeffler, S.; Verbeeck, J.; Zweck, J.; Schattschneider, P.; Rosenauer, A.
Title Atomic electric fields revealed by a quantum mechanical approach to electron picodiffraction Type A1 Journal article
Year 2014 Publication Nature communications Abbreviated Journal Nat Commun
Volume 5 Issue Pages 5653
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract By focusing electrons on probes with a diameter of 50 pm, aberration-corrected scanning transmission electron microscopy (STEM) is currently crossing the border to probing subatomic details. A major challenge is the measurement of atomic electric fields using differential phase contrast (DPC) microscopy, traditionally exploiting the concept of a field- induced shift of diffraction patterns. Here we present a simplified quantum theoretical interpretation of DPC. This enables us to calculate the momentum transferred to the STEM probe from diffracted intensities recorded on a pixel array instead of conventional segmented bright- field detectors. The methodical development yielding atomic electric field, charge and electron density is performed using simulations for binary GaN as an ideal model system. We then present a detailed experimental study of SrTiO3 yielding atomic electric fields, validated by comprehensive simulations. With this interpretation and upgraded instrumentation, STEM is capable of quantifying atomic electric fields and high-contrast imaging of light atoms.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000347227700003 Publication Date 2014-12-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-1723; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.124 Times cited 197 Open Access (up)
Notes 246791 COUNTATOMS; 278510 VORTEX; Hercules; 312483 ESTEEM2; esteem2ta; ECASJO; Approved Most recent IF: 12.124; 2014 IF: 11.470
Call Number UA @ lucian @ c:irua:122835UA @ admin @ c:irua:122835 Serial 166
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Author Jungbauer, M.; Huehn, S.; Egoavil, R.; Tan, H.; Verbeeck, J.; Van Tendeloo, G.; Moshnyaga, V.
Title Atomic layer epitaxy of Ruddlesden-Popper SrO(SrTiO3)n films by means of metalorganic aerosol deposition Type A1 Journal article
Year 2014 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 105 Issue 25 Pages 251603
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report an atomic layer epitaxial growth of Ruddlesden-Popper (RP) thin films of SrO(SrTiO3)(n) (n = infinity, 2, 3, 4) by means of metalorganic aerosol deposition (MAD). The films are grown on SrTiO3(001) substrates by means of a sequential deposition of Sr-O/Ti-O-2 atomic monolayers, monitored in-situ by optical ellipsometry. X-ray diffraction and transmission electron microscopy (TEM) reveal the RP structure with n = 2-4 in accordance with the growth recipe. RP defects, observed by TEM in a good correlation with the in-situ ellipsometry, mainly result from the excess of SrO. Being maximal at the film/substrate interface, the SrO excess rapidly decreases and saturates after 5-6 repetitions of the SrO(SrTiO3)(4) block at the level of 2.4%. This identifies the SrTiO3 substrate surface as a source of RP defects under oxidizing conditions within MAD. Advantages and limitations of MAD as a solution-based and vacuum-free chemical deposition route were discussed in comparison with molecular beam epitaxy. (C) 2014 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000346914000007 Publication Date 2014-12-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951;1077-3118; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 32 Open Access (up)
Notes 246102 IFOX; 278510 VORTEX; 246791 COUNTATOMS; Hercules; 312483 ESTEEM2; esteem2jra3 ECASJO; Approved Most recent IF: 3.411; 2014 IF: 3.302
Call Number UA @ lucian @ c:irua:122830UA @ admin @ c:irua:122830 Serial 172
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Author Turner, S.; Verbeeck, J.; Ramezanipour, F.; Greedan, J.E.; Van Tendeloo, G.; Botton, G.A.
Title Atomic resolution coordination mapping in Ca2FeCoO5 brownmillerite by spatially resolved electron energy-loss spectroscopy Type A1 Journal article
Year 2012 Publication Chemistry of materials Abbreviated Journal Chem Mater
Volume 24 Issue 10 Pages 1904-1909
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Using a combination of high-angle annular dark field scanning transmission electron microscopy and atomically resolved electron energy-loss spectroscopy at high energy resolution in an aberration-corrected electron microscope, we demonstrate the capability of coordination mapping in complex oxides. Brownmillerite compound Ca2FeCoO5, consisting of repetitive octahedral and tetrahedral coordination layers with Fe and Co in a fixed 3+ valency, is selected to demonstrate the principle of atomic resolution coordination mapping. Analysis of the Co-L2,3 and the Fe-L2,3 edges shows small variations in the fine structure that can be specifically attributed to Co/Fe in tetrahedral or in octahedral coordination. Using internal reference spectra, we show that the coordination of the Fe and Co atoms in the compound can be mapped at atomic resolution.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000304237500024 Publication Date 2012-04-25
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 33 Open Access (up)
Notes A.M. Abakumov is thanked for fruitful discussions. S.T. gratefully acknowledges the Fund for Scientific Research Flanders (FWO). J.E.G. and GAB. acknowledge the support of the NSERC of Canada through Discovery Grants. The Canadian Centre for Electron Microscopy is a National Facility supported by NSERC and McMaster University and was funded by the Canada Foundation for Innovation and the Ontario Government. Part of this work was supported by funding from the European Research Council under the FP7, ERC Grant N 246791 COUNTATOMS and ERC Starting Grant N 278510 VORTEX. The EMAT microscope is partially funded by the Hercules fund of the Flemish Government. ECASJO_; Approved Most recent IF: 9.466; 2012 IF: 8.238
Call Number UA @ lucian @ c:irua:98379UA @ admin @ c:irua:98379 Serial 175
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Author Egoavil, R.; Gauquelin, N.; Martinez, G.T.; Van Aert, S.; Van Tendeloo, G.; Verbeeck, J.
Title Atomic resolution mapping of phonon excitations in STEM-EELS experiments Type A1 Journal article
Year 2014 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 147 Issue Pages 1-7
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Atomically resolved electron energy-loss spectroscopy experiments are commonplace in modern aberration-corrected transmission electron microscopes. Energy resolution has also been increasing steadily with the continuous improvement of electron monochromators. Electronic excitations however are known to be delocalized due to the long range interaction of the charged accelerated electrons with the electrons in a sample. This has made several scientists question the value of combined high spatial and energy resolution for mapping interband transitions and possibly phonon excitation in crystals. In this paper we demonstrate experimentally that atomic resolution information is indeed available at very low energy losses around 100 meV expressed as a modulation of the broadening of the zero loss peak. Careful data analysis allows us to get a glimpse of what are likely phonon excitations with both an energy loss and gain part. These experiments confirm recent theoretical predictions on the strong localization of phonon excitations as opposed to electronic excitations and show that a combination of atomic resolution and recent developments in increased energy resolution will offer great benefit for mapping phonon modes in real space.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000343157400001 Publication Date 2014-05-29
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 22 Open Access (up)
Notes 246102 IFOX; 278510 VORTEX; 246791 COUNTATOMS; Hercules; 312483 ESTEEM2; esteem2jra3 ECASJO; Approved Most recent IF: 2.843; 2014 IF: 2.436
Call Number UA @ lucian @ c:irua:118332UA @ admin @ c:irua:118332 Serial 177
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Author Van Aert, S.; Verbeeck, J.; Bals, S.; Erni, R.; van Dyck, D.; Van Tendeloo, G.
Title Atomic resolution mapping using quantitative high-angle annular dark field scanning transmission electron microscopy Type A1 Journal article
Year 2009 Publication Microscopy and microanalysis Abbreviated Journal Microsc Microanal
Volume 15 Issue S:2 Pages 464-465
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge, Mass. Editor
Language Wos 000208119100230 Publication Date 2009-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1431-9276;1435-8115; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.891 Times cited 1 Open Access (up)
Notes Approved Most recent IF: 1.891; 2009 IF: 3.035
Call Number UA @ lucian @ c:irua:96555UA @ admin @ c:irua:96555 Serial 178
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Author Verbeeck, J.; Schattschneider, P.; Lazar, S.; Stöger-Pollach, M.; Löffler, S.; Steiger-Thirsfeld, A.; Van Tendeloo, G.
Title Atomic scale electron vortices for nanoresearch Type A1 Journal article
Year 2011 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 99 Issue 20 Pages 203109-203109,3
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Electron vortex beams were only recently discovered and their potential as a probe for magnetism in materials was shown. Here we demonstrate a method to produce electron vortex beams with a diameter of less than 1.2 Å. This unique way to prepare free electrons to a state resembling atomic orbitals is fascinating from a fundamental physics point of view and opens the road for magnetic mapping with atomic resolution in an electron microscope.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000297786500058 Publication Date 2011-11-17
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 90 Open Access (up)
Notes Hercules Approved Most recent IF: 3.411; 2011 IF: 3.844
Call Number UA @ lucian @ c:irua:93625UA @ admin @ c:irua:93625 Serial 184
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Author Egoavil, R.; Tan, H.; Verbeeck, J.; Bals, S.; Smith, B.; Kuiper, B.; Rijnders, G.; Koster, G.; Van Tendeloo, G.
Title Atomic scale investigation of a PbTiO3/SrRuO3/DyScO3 heterostructure Type A1 Journal article
Year 2013 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 102 Issue 22 Pages 223106-5
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract An epitaxial PbTiO3 thin film grown on self-organized crystalline SrRuO3 nanowires deposited on a DyScO3 substrate with ordered DyO and ScO2 chemical terminations is investigated by transmission electron microscopy. In this PbTiO3/SrRuO3/DyScO3 heterostructure, the SrRuO3 nanowires are assumed to grow on only one type of substrate termination. Here, we report on the structure, morphology, and chemical composition analysis of this heterostructure. Electron energy loss spectroscopy reveals the exact termination sequence in this complex structure. The energy loss near-edge structure of the Ti-L-2,L-3, Sc-L-2,L-3, and O K edges shows intrinsic interfacial electronic reconstruction. Furthermore, PbTiO3 domain walls are observed to start at the end of the nanowires resulting in atomic steps on the film surface. (C) 2013 AIP Publishing LLC.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000320621600070 Publication Date 2013-06-05
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 (up)
Notes Ifox; Esteem2; Countatoms; Vortex; esteem2jra3 ECASJO; Approved Most recent IF: 3.411; 2013 IF: 3.515
Call Number UA @ lucian @ c:irua:109606UA @ admin @ c:irua:109606 Serial 185
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Author Barbier, M.; Vasilopoulos, P.; Peeters, F.M.; Pereira, J.M.
Title Band structure, density of states, and transmission in graphene bilayer superlattices Type A1 Journal article
Year 2009 Publication AIP conference proceedings Abbreviated Journal
Volume 1199 Issue Pages 547-548
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The energy spectrum and density of states of graphene bilayer superlattices (SLs) are evaluated. We take into account doping and/or gating of the layers as well as tunnel coupling between them. In addition, we evaluate the transmission through such SLs and through single or double barriers. The transmission exhibits a strong dependence on the direction of the incident wave vector.
Address
Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos 000281590800258 Publication Date 2010-01-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access (up)
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:84893 Serial 217
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Author Maistrenko, Y.L.; Vasylenko, A.; Sudakov, O.; Levchenko, R.; Maistrenko, V.L.
Title Cascades of multiheaded chimera states for coupled phase oscillators Type A1 Journal article
Year 2014 Publication International journal of bifurcation and chaos in applied sciences and engineering Abbreviated Journal Int J Bifurcat Chaos
Volume 24 Issue 8 Pages 1440014
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Chimera state is a recently discovered dynamical phenomenon in arrays of nonlocally coupled oscillators, that displays a self-organized spatial pattern of coexisting coherence and incoherence. We discuss the appearance of the chimera states in networks of phase oscillators with attractive and with repulsive interactions, i.e. when the coupling respectively favors synchronization or works against it. By systematically analyzing the dependence of the spatiotemporal dynamics on the level of coupling attractivity/repulsivity and the range of coupling, we uncover that different types of chimera states exist in wide domains of the parameter space as cascades of the states with increasing number of intervals of irregularity, so-called chimera's heads. We report three scenarios for the chimera birth: (1) via saddle-node bifurcation on a resonant invariant circle, also known as SNIC or SNIPER, (2) via blue-sky catastrophe, when two periodic orbits, stable and saddle, approach each other creating a saddle-node periodic orbit, and (3) via homoclinic transition with complex multistable dynamics including an “eight-like” limit cycle resulting eventually in a chimera state.
Address
Corporate Author Thesis
Publisher Place of Publication Singapore Editor
Language Wos 000341494900015 Publication Date 2014-08-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0218-1274;1793-6551; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.329 Times cited Open Access (up)
Notes Approved Most recent IF: 1.329; 2014 IF: 1.078
Call Number UA @ lucian @ c:irua:119303 Serial 285
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