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	Author	Ranieri, P.; Shrivastav, R.; Wang, M.; Lin, A.; Fridman, G.; Fridman, A.A.; Han, L.-H.; Miller, V.
	Title	Nanosecond-pulsed dielectric barrier dischargeinduced antitumor effects propagate through depth of tissue via intracellular signaling			Type	A1 Journal article
	Year	2017	Publication	Plasma medicine	Abbreviated Journal
	Volume	7	Issue	3	Pages	283-297
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Studies using xenograft mouse models have shown that plasma applied to the skin overlying tumors results in tumor shrinkage. Plasma is considered a nonpenetrating treatment; however, these studies demonstrate plasma effects that occur beyond the postulated depth of physical penetration of plasma components. The present study examines the propagation of plasma effects through a tissue model using three-dimensional, cell-laden extracellular matrices (ECMs). These ECMs are used as barriers against direct plasma penetration. By placing them onto a monolayer of target cancer cells to create an in-vitro analog to in-vivo studies, we distinguished between cellular effects from direct plasma exposure and cellular effects due to cell-to-cell signaling stimulated by plasma. We show that nanosecond-pulsed dielectric barrier discharge plasma treatment applied atop an acellular barrier impedes the externalization of calreticulin (CRT) in the target cells. In contrast, when a barrier is populated with cells, CRT externalization is restored. Thus, we demonstrate that plasma components stimulate signaling among cells embedded in the barrier to transfer plasma effects to the target cells.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	2017-09-01
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:155658			Serial	8293
Permanent link to this record



	Author	Bliokh, K.Y.; Ivanov, I.P.; Guzzinati, G.; Clark, L.; Van Boxem, R.; Béché, A.; Juchtmans, R.; Alonso, M.A.; Schattschneider, P.; Nori, F.; Verbeeck, J.
	Title	Theory and applications of free-electron vortex states			Type	A1 Journal article
	Year	2017	Publication	Physics reports	Abbreviated Journal	Phys Rep
	Volume	690	Issue	690	Pages	1-70
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Both classical and quantum waves can form vortices: with helical phase fronts and azimuthal current densities. These features determine the intrinsic orbital angular momentum carried by localized vortex states. In the past 25 years, optical vortex beams have become an inherent part of modern optics, with many remarkable achievements and applications. In the past decade, it has been realized and demonstrated that such vortex beams or wavepackets can also appear in free electron waves, in particular, in electron microscopy. Interest in free-electron vortex states quickly spread over different areas of physics: from basic aspects of quantum mechanics, via applications for fine probing of matter (including individual atoms), to high-energy particle collision and radiation processes. Here we provide a comprehensive review of theoretical and experimental studies in this emerging field of research. We describe the main properties of electron vortex states, experimental achievements and possible applications within transmission electron microscopy, as well as the possible role of vortex electrons in relativistic and high-energy processes. We aim to provide a balanced description including a pedagogical introduction, solid theoretical basis, and a wide range of practical details. Special attention is paid to translate theoretical insights into suggestions for future experiments, in electron microscopy and beyond, in any situation where free electrons occur.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000406169900001	Publication Date	2017-05-29
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0370-1573	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	17.425	Times cited	210	Open Access	OpenAccess
	Notes	AFOSR, FA9550-14-1-0040 ; CREST, JPMJCR1676 ; Portuguese Fundação para a Ciência e a Tecnologia (FCT), IF/00989/2014/CP1214/CT0004 ; Austrian Science Fund, I543-N20 ; ERC, 278510 VORTEX ; We acknowledge discussions with Mark R. Dennis and Andrei Afanasev. This work was supported by the RIKEN Interdisciplinary Theoretical Science Research Group (iTHES) Project, the Multi-University Research Initiative (MURI) Center for Dynamic Magneto-Optics via the Air Force Office of Scientific Research (AFOSR) (Grant No. FA9550-14-1-0040), Grant-in-Aid for Scientific Research (A), Core Research for Evolutionary Science and Technology (CREST), the John Templeton Foundation, the Australian Research Council, the Portuguese Funda¸c˜ao para a Ciˆencia e a Tecnologia (FCT) (contract IF/00989/2014/CP1214/CT0004 under the IF2014 Program), contracts UID/FIS/00777/2013 and CERN/FIS-NUC/0010/2015 (partially funded through POCTI, COMPETE, QREN, and the European Union), Austrian Science Fund Grant No. I543-N20, the European Research Council under the 7th Framework Program (FP7) (ERC Starting Grant No. 278510 VORTEX), and FWO PhD Fellowship grants (Aspirant Fonds Wetenschappelijk OnderzoekVlaanderen).			Approved	Most recent IF: 17.425
	Call Number	EMAT @ emat @ c:irua:143262			Serial	4574
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	Author	van der Torren, A.J.H.; Liao, Z.; Xu, C.; Gauquelin, N.; Yin, C.; Aarts, J.; van der Molen, S.J.
	Title	Formation of a conducting LaAlO₃/SrTiO₃ interface studied by low-energy electron reflection during growth			Type	A1 Journal Article
	Year	2017	Publication	Physical Review Materials	Abbreviated Journal	Phys. Rev. Materials
	Volume	1	Issue	7	Pages	075001
	Keywords	A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
	Abstract	The two-dimensional electron gas occurring between the band insulators SrTiO 3 and LaAlO 3 continues to attract considerable interest, due to the possibility of dynamic control over the carrier density, and the ensuing phenomena such as magnetism and superconductivity. The formation of this conducting interface is sensitive to the growth conditions, but despite numerous investigations, there are still questions about the details of the physics involved. In particular, not much is known about the electronic structure of the growing LaAlO 3 layer at the growth temperature (around 800 ◦ C) in oxygen (pressure around 5 × 10 −5 mbar), since analysis techniques at these conditions are not readily available. We developed a pulsed laser deposition system inside a low-energy electron microscope in order to study this issue. The setup allows for layer-by-layer growth control and in-situ measurements of the angle-dependent electron reflection intensity, which can be used as a fingerprint of the electronic structure of the surface layers during growth. By using different substrate terminations and growth conditions we observe two families of reflectivity maps, which we can connect either to samples with an AlO 2 -rich surface and a conducting interface; or to samples with a LaO-rich surface and an insulating interface. Our observations emphasize that substrate termination and stoichiometry determine the electronic structure of the growing layer, and thereby the conductance of the interface.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000418770200003	Publication Date	2017-12-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2475-9953	ISBN		Additional Links
	Impact Factor		Times cited	2	Open Access	Not_Open_Access
	Notes	Nederlandse Organisatie voor Wetenschappelijk Onderzoek; Fonds Wetenschappelijk Onderzoek, G.0044.13N ; European Cooperation in Science and Technology, MP 1308 ; We want to acknowledge Ruud Tromp, Daniel Gee- len, Johannes Jobst, Regina Dittmann, Gert Jan Koster, Guus Rijnders and Jo Verbeek for discussions and ad- vice and Ruud van Egmond and Marcel Hesselberth for technical assistance. This work was supported by the Netherlands Organization for Scientific Research (NWO) by means of an ”NWO Groot” grant and by the Leiden- Delft Consortium NanoFront. The work is part of the re- search programmes NWOnano and DESCO, which are fi- nanced by NWO. N.G. acknowledges funding through the GOA project “Solarpaint” of the University of Antwerp and from the FWO project G.0044.13N (Charge order- ing). The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. We would also like to acknowledge networking support by the COST Action MP 1308 (COST TO-BE).			Approved	Most recent IF: NA
	Call Number	EMAT @ emat @			Serial	4903
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	Author	Conti, S.; Perali, A.; Peeters, F.M.; Neilson, D.
	Title	Multicomponent electron-hole superfluidity and the BCS-BEC crossover in double bilayer graphene			Type	A1 Journal article
	Year	2017	Publication	Physical review letters	Abbreviated Journal	Phys Rev Lett
	Volume	119	Issue	25	Pages	257002
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	<script type='text/javascript'>document.write(unpmarked('Superfluidity in coupled electron-hole sheets of bilayer graphene is predicted here to be multicomponent because of the conduction and valence bands. We investigate the superfluid crossover properties as functions of the tunable carrier densities and the tunable energy band gap Eg. For small band gaps there is a significant boost in the two superfluid gaps, but the interaction-driven excitations from the valence to the conduction band can weaken the superfluidity, even blocking the system from entering the Bose-Einstein condensate (BEC) regime at low densities. At a given larger density, a band gap E-g similar to 80-120 meV can carry the system into the strong-pairing multiband BCS-BEC crossover regime, the optimal range for realization of high-Tc superfluidity.'));
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000418619100017	Publication Date	2017-12-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-9007	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.462	Times cited	18	Open Access
	Notes	; We thank Mohammad Zarenia for useful discussions. Part of this work was supported by FWO-VI (Flemish Science Foundation) and the Methusalem program. ;			Approved	Most recent IF: 8.462
	Call Number	UA @ lucian @ c:irua:148509			Serial	4885
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	Author	Groenendijk, D.J.; Autieri, C.; Girovsky, J.; Martinez-Velarte, M.C.; Manca, N.; Mattoni, G.; Monteiro, A.M.R.V.L.; Gauquelin, N.; Verbeeck, J.; Otte, A.F.; Gabay, M.; Picozzi, S.; Caviglia, A.D.
	Title	Spin-orbit semimetal SrIrO₃ in the two-dimensional limit			Type	A1 Journal article
	Year	2017	Publication	Physical review letters	Abbreviated Journal	Phys Rev Lett
	Volume	119	Issue	25	Pages	256403
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	<script type='text/javascript'>document.write(unpmarked('We investigate the thickness-dependent electronic properties of ultrathin SrIrO3 and discover a transition from a semimetallic to a correlated insulating state below 4 unit cells. Low-temperature magnetoconductance measurements show that spin fluctuations in the semimetallic state are significantly enhanced while approaching the transition point. The electronic properties are further studied by scanning tunneling spectroscopy, showing that 4 unit cell SrIrO(3)d is on the verge of a gap opening. Our density functional theory calculations reproduce the critical thickness of the transition and show that the opening of a gap in ultrathin SrIrO3 requires antiferromagnetic order.'));
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	New York, N.Y.	Editor
	Language		Wos	000418619100014	Publication Date	2017-12-22
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0031-9007	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	8.462	Times cited	79	Open Access	OpenAccess
	Notes	; This work was supported by The Netherlands Organisation for Scientific Research (NWO/OCW) as part of the Frontiers of Nanoscience program (NanoFront), by the Dutch Foundation for Fundamental Research on Matter (FOM), and by the European Research Council under the European Union's H2020 programme/ERC Grant Agreement No. [677458]. The authors thank R. Claessen, P. Schutz, D. Di Sante, G. Sangiovanni, and A. Santander Syro for useful discussions. M. G. gratefully acknowledges support from the French National Research Agency (ANR) (Project LACUNES No. ANR-13-BS04-0006-01). C. A. and S. P. acknowledge financial support from Fondazione Cariplo via the project Magister (Project No. 2013-0726) and from CNR-SPIN via the Seed Project “CAMEO”. N. G. and J. V. acknowledge support from the GOA project “Solarpaint” of the University of Antwerp. The Qu-AntEM microscope was partly funded by the Hercules fund from the Flemish Government. ;			Approved	Most recent IF: 8.462
	Call Number	UA @ lucian @ c:irua:148510			Serial	4897
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	Author	Yang, W.; Misko, V.R.; Tempère, J.; Kong, M.; Peeters, F.M.
	Title	Artificial living crystals in confined environment			Type	A1 Journal article
	Year	2017	Publication	Physical Review E	Abbreviated Journal	Phys Rev E
	Volume	95	Issue	6	Pages	062602
	Keywords	A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT)
	Abstract	Similar to the spontaneous formation of colonies of bacteria, flocks of birds, or schools of fish, “living crystals” can be formed by artificial self-propelled particles such as Janus colloids. Unlike usual solids, these “crystals” are far from thermodynamic equilibrium. They fluctuate in time forming a crystalline structure, breaking apart and re-forming again. We propose a method to stabilize living crystals by applying a weak confinement potential that does not suppress the ability of the particles to perform self-propelled motion, but it stabilizes the structure and shape of the dynamical clusters. This gives rise to such configurations of living crystals as “living shells” formed by Janus colloids. Moreover, the shape of the stable living clusters can be controlled by tuning the potential strength. Our proposal can be verified experimentally with either artificial microswimmers such as Janus colloids, or with living active matter.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000402667600006	Publication Date	2017-06-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2470-0045;2470-0053;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.366	Times cited	10	Open Access
	Notes	; This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Research Foundation (FWO-Vl) (Belgium), the Flemish Research Foundation (through Projects No. G.0115.12N, No. G.0119.12N, No. G.0122.12N, and No. G.0429.15N), and the Research Fund of the University of Antwerp. W.Y. acknowledges the support from the National Natural Science Foundation of China under Grants No. 11204199 and No. 51135007, the China Scholarship Council, the 131 project and the Program for the Outstanding Innovative Teams of Higher Learning Institutions of Shanxi, and a project under Grant No. 2016-096 by Shanxi Scholarship Council of China. ;			Approved	Most recent IF: 2.366
	Call Number	UA @ lucian @ c:irua:144205			Serial	4641
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	Author	Domingos, J.L.C.; Peeters, F.M.; Ferreira, W.P.
	Title	Self-assembly of rigid magnetic rods consisting of single dipolar beads in two dimensions			Type	A1 Journal article
	Year	2017	Publication	Physical review E	Abbreviated Journal	Phys Rev E
	Volume	96	Issue	1	Pages	012603
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Molecular dynamics simulations are used to investigate the structural properties of a two-dimensional ensemble of magnetic rods, which are modeled as aligned single dipolar beads. The obtained self-assembled configurations can be characterized as (1) clusters, (2) percolated, and (3) ordered structures, and their structural properties are investigated in detail. By increasing the aspect ratio of the magnetic rods, we show that the percolation transition is suppressed due to the reduced mobility of the rods in two dimensions. Such a behavior is opposite to the one observed in three dimensions. A magnetic bulk phase is found with local ferromagnetic order and an unusual nonmonotonic behavior of the nematic order is observed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000405713900014	Publication Date	2017-07-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2470-0045;2470-0053;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.366	Times cited	8	Open Access
	Notes	; This work was supported by the Brazilian agencies FUNCAP, CAPES, program Science without borders, and CNPq (Project No. 400748/2013-4), the joint CNPq-FWO bilateral project, and the Flemish Science Foundation (FWO-V1). ;			Approved	Most recent IF: 2.366
	Call Number	UA @ lucian @ c:irua:145210			Serial	4723
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	Author	de Araujo, J.L.B.; Munarin, F.F.; Farias, G.A.; Peeters, F.M.; Ferreira, W.P.
	Title	Structure and reentrant percolation in an inverse patchy colloidal system			Type	A1 Journal article
	Year	2017	Publication	Physical Review E	Abbreviated Journal
	Volume	95	Issue	6	Pages	062606
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Two-dimensional systems of inverse patchy colloids modeled as disks with a central charge and having their surface decorated with oppositely pointlike charged patches are investigated using molecular dynamics simulations. The self-assembly of the patchy colloids leads to diverse ground state configurations ranging from crystalline arrangements of monomers to linear clusters, ramified linear clusters and to percolated configurations. Two structural phase diagrams are constructed: (1) as a function of the net charge and area fraction, and (2) as a function of the net charge and the range of the pair interaction potential. An interesting reentrant percolation transition is obtained as a function of the net charge of the colloids. We identify distinct mechanisms that lead to the percolation transition.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000404545700005	Publication Date	2017-06-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	5	Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:152628			Serial	8587
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	Author	Stosic, D.; Mulkers, J.; Van Waeyenberge, B.; Ludermir, T.B.; Milošević, M.V.
	Title	Paths to collapse for isolated skyrmions in few-monolayer ferromagnetic films			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	21	Pages	214418
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Magnetic skyrmions are topological spin configurations in materials with chiral Dzyaloshinskii-Moriya interaction (DMI), that are potentially useful for storing or processing information. To date, DMI has been found in few bulk materials, but can also be induced in atomically thin magnetic films in contact with surfaces with large spin-orbit interactions. Recent experiments have reported that isolated magnetic skyrmions can be stabilized even near room temperature in few-atom-thick magnetic layers sandwiched between materials that provide asymmetric spin-orbit coupling. Here we present the minimum-energy path analysis of three distinct mechanisms for the skyrmion collapse, based on ab initio input and the performed atomic-spin simulations. We focus on the stability of a skyrmion in three atomic layers of Co, either epitaxial on the Pt(111) surface or within a hybrid multilayer where DMI nontrivially varies per monolayer due to competition between different symmetry breaking from two sides of the Co film. In laterally finite systems, their constrained geometry causes poor thermal stability of the skyrmion toward collapse at the boundary, which we show to be resolved by designing the high-DMI structure within an extended film with lower or no DMI.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000404015500001	Publication Date	2017-06-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	48	Open Access
	Notes	This work was supported by the Research Foundation, Flanders (FWO-Vlaanderen) and Brazilian agency CNPq (Grants No. 442668/2014-7 and No. 140840/2016-8).			Approved	Most recent IF: 3.836
	Call Number	CMT @ cmt @c:irua:144865			Serial	4704
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	Author	Callewaert, V.; Saniz, R.; Barbiellini, B.; Bansil, A.; Partoens, B.
	Title	Application of the weighted-density approximation to the accurate description of electron-positron correlation effects in materials			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	96	Issue	8	Pages	085135
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We discuss positron-annihilation lifetimes for a set of illustrative bulk materials within the framework of the weighted-density approximation (WDA). The WDA can correctly describe electron-positron correlations in strongly inhomogeneous systems, such as surfaces, where the applicability of (semi-)local approximations is limited. We analyze the WDA in detail and show that the electrons which cannot screen external charges efficiently, such as the core electrons, cannot be treated accurately via the pair correlation of the homogeneous electron gas. We discuss how this problem can be addressed by reducing the screening in the homogeneous electron gas by adding terms depending on the gradient of the electron density. Further improvements are obtained when core electrons are treated within the LDA and the valence electron using the WDA. Finally, we discuss a semiempirical WDA-based approach in which a sum rule is imposed to reproduce the experimental lifetimes.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000408342600003	Publication Date	2017-08-24
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	6	Open Access
	Notes	Fonds Wetenschappelijk Onderzoek, G. 0224.14N ; U.S. Department of Energy, DE-FG02-07ER46352 DE-AC02-05CH11231 DE-SC0012575 ;			Approved	Most recent IF: 3.836
	Call Number	CMT @ cmt @c:irua:145703			Serial	4703
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	Author	Li, L.L.; Moldovan, D.; Vasilopoulos, P.; Peeters, F.M.
	Title	Aharonov-Bohm oscillations in phosphorene quantum rings			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	20	Pages	205426
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The Aharonov-Bohm (AB) effect in square phosphorene quantum rings, with armchair and zigzag edges, is investigated using the tight-binding method. The energy spectra and wave functions of such rings, obtained as a function of the magnetic flux Phi threading the ring, are strongly influenced by the ringwidthW, an in-plane electric field E-p, and a side-gating potential V-g. Compared to a square dot, the ring shows an enhanced confinement due to its inner edges and an interedge coupling along the zigzag direction, both of which strongly affect the energy spectrum and the wave functions. The energy spectrum that is gapped consists of a regular part, of conduction (valence) band states, that shows the usual AB oscillations in the higher-(lower-) energy region, and of edge states, in the gap, that exhibit no AB oscillations. As the width W decreases, the AB oscillations become more distinct and regular and their period is close to Phi(0)/2, where the flux quantum Phi(0) = h/e is the period of an ideal circular ring (W -> 0). Both the electric field E-p and the side-gating potential V-g reduce the amplitude of the AB oscillations. The amplitude can be effectively tuned by E-p or V-g and exhibits an anisotropic behavior for different field directions or side-gating configurations.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000402003700010	Publication Date	2017-05-23
	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	16	Open Access
	Notes	; This work was financially supported by the Chinese Academy of Sciences, the Flemish Science Foundation (FWO-V1), and by the Canadian NSERC Grant No. OGP0121756 (P.V.). ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:144267			Serial	4638
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	Author	Mulkers, J.; Van Waeyenberge, B.; Milošević, M.V.
	Title	Effects of spatially engineered Dzyaloshinskii-Moriya interaction in ferromagnetic films			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	95	Pages	144401
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The Dzyaloshinskii-Moriya interaction (DMI) is a chiral interaction that favors formation of domain walls. Recent experiments and ab initio calculations show that there are multiple ways to modify the strength of the interfacially induced DMI in thin ferromagnetic films with perpendicular magnetic anisotropy. In this paper we reveal theoretically the effects of spatially varied DMI on the magnetic state in thin films. In such heterochiral 2D structures we report several emergent phenomena, ranging from the equilibrium spin canting at the interface between regions with different DMI, over particularly strong confinement of domain walls and skyrmions within high-DMI tracks, to advanced applications such as domain tailoring nearly at will, design of magnonic waveguides, and much improved skyrmion racetrack memory.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000399382100003	Publication Date	2017-04-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	60	Open Access
	Notes	Fonds Wetenschappelijk Onderzoek, G098917N ;			Approved	Most recent IF: 3.836
	Call Number	CMT @ cmt @ c:irua:141917			Serial	4534
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	Author	Li, L.L.; Zarenia, M.; Xu, W.; Dong, H.M.; Peeters, F.M.
	Title	Exciton states in a circular graphene quantum dot: Magnetic field induced intravalley to intervalley transition			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	95	Pages	045409
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The magnetic-field dependence of the energy spectrum, wave function, binding energy, and oscillator strength of exciton states confined in a circular graphene quantum dot (CGQD) is obtained within the configuration interaction method. We predict that (i) excitonic effects are very significant in the CGQD as a consequence of a combination of geometric confinement, magnetic confinement, and reduced screening; (ii) two types of excitons (intravalley and intervalley) are present in the CGQD because of the valley degree of freedom in graphene; (iii) the intravalley and intervalley exciton states display different magnetic-field dependencies due to the different electron-hole symmetries of the single-particle energy spectra; (iv) with increasing magnetic field, the exciton ground state in the CGQD undergoes an intravalley to intervalley transition accompanied by a change of angular momentum; (v) the exciton binding energy does not increase monotonically with the magnetic field due to the competition between geometric and magnetic confinements; and (vi) the optical transitions of the intervalley and intravalley excitons can be tuned by the magnetic field, and valley-dependent excitonic transitions can be realized in a CGQD.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000391856000006	Publication Date	2017-01-12
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9950;2469-9969;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	14	Open Access
	Notes	; This work was financially supported by the China Scholarship Council (CSC), the Flemish Science Foundation (FWO-Vl), the National Natural Science Foundation of China (Grants No. 11304316, No. 11574319, and No. 11604380), and by the Chinese Academy of Sciences (CAS). ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:141444			Serial	4555
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	Author	Satarifard, V.; Mousaei, M.; Hadadi, F.; Dix, J.; Sobrino Fernández, M.; Carbone, P.; Beheshtian, J.; Peeters, F.M.; Neek-Amal, M.
	Title	Reversible structural transition in nanoconfined ice			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	95	Pages	064105
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The report on square ice sandwiched between two graphene layers by Algara-Siller et al. [Nature (London) 519, 443 (2015)] has generated a large interest in this system. By applying high lateral pressure on nanoconfined water, we found that monolayer ice is transformed to bilayer ice when the two graphene layers are separated by H = 6,7 angstrom. It was also found that three layers of a denser phase of ice with smaller lattice constant are formed if we start from bilayer ice and apply a lateral pressure of about 0.7 GPa with H = 8,9 angstrom. The lattice constant (2.5-2.6 angstrom) in both transitions is found to be smaller than those typical for the known phases of ice and water, i.e., 2.8 angstrom. We validate these results using ab initio calculations and find good agreement between ab initio O-O distance and those obtained from classical molecular dynamics simulations. The reversibility of the mentioned transitions is confirmed by decompressing the systems.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000393943300005	Publication Date	2017-02-16
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9950;2469-9969;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	23	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:141994			Serial	4558
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	Author	Han, F.W.; Xu, W.; Li, L.L.; Zhang, C.; Dong, H.M.; Peeters, F.M.
	Title	Electronic and transport properties of n-type monolayer black phosphorus at low temperatures			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	95	Pages	115436
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We present a detailed theoretical study of the electronic and transport properties of monolayer black phosphorus (BP). This study is motivated by recent experimental activities in investigating n-type few-layer BP systems. The electron density of states, the screening length, and the low-temperature electron mobility are calculated for monolayer BP (MLBP). In particular, the electron transport mobilities along the armchair and zigzag directions are examined on the basis of the momentum-balance equation derived from a semiclassical Boltzmann equation. The anisotropic electron mobilities in MLBP along different directions are demonstrated where the electron-impurity scattering is considered. Furthermore, we compare the results obtained from two electronic band structures of MLBP and find that the simplified model can describe quite rightly the electronic and transport properties of MLBP. This study is relevant to the application of few-layer BP based electronic systems as advanced electronic devices.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000399140700012	Publication Date	2017-03-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	12	Open Access
	Notes	National Natural Science Foundation of China, 11574319 11304316 11304317 11604380 ; Ministry of Science and Technology of the People's Republic of China, 2011YQ130018 ; Chinese Academy of Sciences;			Approved	Most recent IF: 3.836
	Call Number	CMT @ cmt @ c:irua:142431			Serial	4564
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	Author	Zhao, H.J.; Misko, V.R.; Tempere, J.; Nori, F.
	Title	Pattern formation in vortex matter with pinning and frustrated intervortex interactions			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	95	Pages	104519
	Keywords	A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT)
	Abstract	We investigate the effects related to vortex-core deformations when vortices approach each other. As a result of these vortex-core deformations, the vortex-vortex interaction effectively acquires an attractive component leading to a variety of vortex patterns typical for systems with nonmonotonic repulsive-attractive interaction, such as stripes and labyrinths. The core deformations are anisotropic and can induce frustration in the vortex-vortex interaction. In turn, this frustration has an impact on the resulting vortex patterns, which are analyzed in the presence of additional random pinning, as a function of the pinning strength. This analysis can be applicable to vortices in multiband superconductors or to vortices in Bose-Einstein condensates.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000399138800006	Publication Date	2017-03-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9969; 2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	5	Open Access
	Notes	; We acknowledge fruitful discussions with E. Babaev and V. Gladilin. This work is partially supported by the Natural Science Foundation of Jiangsu Province (Grant No. BK20150595), the National Natural Science Foundation of China (Grants No. NSFC-U1432135, No. 11611140101, and No. 11674054), the “Odysseus” program of the Flemish Government and Flemish Research Foundation (FWO-Vl), the Flemish Research Foundation (through Projects No. G.0115.12N, No. G.0119.12N, No. G.0122.12N, and No. G.0429.15N), the Research Fund of the University of Antwerp, the RIKEN iTHES Project, the MURI Center for Dynamic Magneto-Optics via the AFOSR Award No. FA9550-14-1-0040, the IMPACT program of JST, a Grant-in-Aid for Scientific Research (A), the Japan Society for the Promotion of Science (KAKENHI), CREST, and a grant from the John Templeton Foundation. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:142429			Serial	4602
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	Author	Michel, K.H.; Çakir, D.; Sevik, C.; Peeters, F.M.
	Title	Piezoelectricity in two-dimensional materials : comparative study between lattice dynamics and ab initio calculations			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	95	Pages	125415
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The elastic constant C-11 and piezoelectric stress constant e(1),(11) of two-dimensional (2D) dielectric materials comprising h-BN, 2H-MoS2, and other transition-metal dichalcogenides and dioxides are calculated using lattice dynamical theory. The results are compared with corresponding quantities obtained with ab initio calculations. We identify the difference between clamped-ion and relaxed-ion contributions with the dependence on inner strains which are due to the relative displacements of the ions in the unit cell. Lattice dynamics allows us to express the inner-strain contributions in terms of microscopic quantities such as effective ionic charges and optoacoustical couplings, which allows us to clarify differences in the piezoelectric behavior between h-BN and MoS2. Trends in the different microscopic quantities as functions of atomic composition are discussed.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000396013400005	Publication Date	2017-03-11
	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	29	Open Access
	Notes	; The authors acknowledge useful discussions with L. Wirtz and A. Molina-Sanchez. This work was supported by the Methusalem program and the Fonds voor Wetenschappelijk Onderzoek-Vlaanderen. Computational resources were provided by HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:142444			Serial	4603
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	Author	De Beule, C.; Zarenia, M.; Partoens, B.
	Title	Transmission in graphene-topological insulator heterostructures			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	95	Pages	115424
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We investigate scattering of the topological surface state of a three-dimensional time-reversal invariant topological insulator when graphene is deposited on the topological-insulator surface. Specifically, we consider the (111) surface of a Bi2Se3-like topological insulator. We present a low-energy model for the graphene-topological insulator heterostructure and we calculate the transmission probability at zigzag and armchair edges of the deposited graphene, and the conductance through graphene nanoribbon barriers, and show that its features can be understood from antiresonances in the transmission probability.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000399216700004	Publication Date	2017-03-22
	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	4	Open Access
	Notes	; The authors would like to thank B. Van Duppen for interesting discussions. This work was supported by the Flemish Research Foundation (FWO) through the Aspirant Fellowship of Christophe De Beule. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:143652			Serial	4609
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	Author	de Sousa, G.O.; da Costa, D.R.; Chaves, A.; Farias, G.A.; Peeters, F.M.
	Title	Unusual quantum confined Stark effect and Aharonov-Bohm oscillations in semiconductor quantum rings with anisotropic effective masses			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	95	Pages	205414
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The effects of external electric and magnetic fields on the energy spectrum of quantum rings made out of a bidimensional semiconductor material with anisotropic band structures are investigated within the effective-mass model. The interplay between the effective-mass anisotropy and the radial confinement leads to wave functions that are strongly localized at two diametrically opposite regions where the kinetic energy is lowest due to the highest effective mass. We show that this quantum phenomenon has clear consequences on the behavior of the energy states in the presence of applied in-plane electric fields and out-of-plane magnetic fields. In the former, the quantum confined Stark effect is observed with either linear or quadratic shifts, depending on the direction of the applied field. As for the latter, the usual Aharonov-Bohm oscillations are not observed for a circularly symmetric confining potential, however they can be reinstated if an elliptic ring with an appropriate aspect ratio is chosen.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000401230600007	Publication Date	2017-05-12
	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; WoS citing articles
	Impact Factor	3.836	Times cited	19	Open Access
	Notes	; This work was financially supported by CNPq under the PRONEX/FUNCAP grants, CAPES Foundation, the Flemish Science Foundation (FWO-Vl), and the Brazilian Program Science Without Borders (CsF). ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:143746			Serial	4610
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	Author	Zarenia, M.; Neilson, D.; Partoens, B.; Peeters, F.M.
	Title	Wigner crystallization in transition metal dichalcogenides : a new approach to correlation energy			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	95	Pages	115438
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We introduce a new approach for the correlation energy of one- and two-valley two-dimensional electron gas (2DEG) systems. Our approach is based on an interpolation between two limits, a random phase approximation at high densities and a classical approach at low densities which gives excellent agreement with available Quantum Monte Carlo (QMC) calculations. The two-valley 2DEG model is introduced to describe the electron correlations in monolayer transition metal dichalcogenides (TMDs). We study the zero-temperature transition from a Fermi liquid to a quantum Wigner crystal phase in monolayer TMDs. Consistent with QMC, we find that electrons crystallize at r(s) = 31 in one-valley 2DEG. For two valleys, we predict Wigner crystallization at r(s) = 30, implying that valley degeneracy has little effect on the critical r(s), in contrast to an earlier claim.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000399141200003	Publication Date	2017-03-30
	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	18	Open Access
	Notes	; This work was partially supported by the Flanders Research Foundation (FWO) and the Methusalem program of the Flemish government. D.N. acknowledges support by the University of Camerino FAR project CESEMN. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:142428			Serial	4613
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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	Houben, K.; Couet, S.; Trekels, M.; Menendez, E.; Peissker, T.; Seo, J.W.; Hu, M.Y.; Zhao, J.Y.; Alp, E.E.; Roelants, S.; Partoens, B.; Milošević, M.V.; Peeters, F.M.; Bessas, D.; Brown, S.A.; Vantomme, A.; Temst, K.; Van Bael, M.J.
	Title	Lattice dynamics in Sn nanoislands and cluster-assembled films			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	15	Pages	155413
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	To unravel the effects of phonon confinement, the influence of size and morphology on the atomic vibrations is investigated in Sn nanoislands and cluster-assembled films. Nuclear resonant inelastic x-ray scattering is used to probe the phonon densities of states of the Sn nanostructures which show significant broadening of the features compared to bulk phonon behavior. Supported by ab initio calculations, the broadening is attributed to phonon scattering and can be described within the damped harmonic oscillator model. Contrary to the expectations based on previous research, the appearance of high-energy modes above the cutoff energy is not observed. From the thermodynamic properties extracted from the phonon densities of states, it was found that grain boundary Sn atoms are bound by weaker forces than bulk Sn atoms.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000401762400008	Publication Date	2017-04-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9969; 2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	5	Open Access
	Notes	; This work was supported by the Research Foundation-Flanders (FWO) and the Concerted Research Action (GOA/14/007). The authors acknowledge Hercules stichting (Projects No. AKUL/13/19 and No. AKUL/13/25). K.H. and S.C. thank the FWO for financial support. T.P. acknowledges the IWT for financial support. S.R., M.V.M., and B.P. acknowledge TOPBOF funding of the University of Antwerp Research Fund. J.W.S. acknowledges Hercules Stichting (Project No. AKUL/13/19). The authors want to thank R. Lieten for help with the XRD measurements and T. Picot for fruitful discussions. The authors gratefully acknowledge R. Ruffer and A. I. Chumakov for fruitful discussions and the European Synchrotron Radiation Facility for the measurement of the SnO<INF>2</INF> powder at the Nuclear Resonance beamline (ID-18). This research used resources of the Advanced Photon Source, a US Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:144305			Serial	4667
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	Author	Kleibert, A.; Balan, A.; Yanes, R.; Derlet, P.M.; Vaz, C.A.F.; Timm, M.; Fraile Rodríguez, A.; Béché, A.; Verbeeck, J.; Dhaka, R.S.; Radovic, M.; Nowak, U.; Nolting, F.
	Title	Direct observation of enhanced magnetism in individual size- and shape-selected 3d transition metal nanoparticles			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	95	Issue	95	Pages	195404
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Magnetic nanoparticles are critical building blocks for future technologies ranging from nanomedicine to spintronics. Many related applications require nanoparticles with tailored magnetic properties. However, despite significant efforts undertaken towards this goal, a broad and poorly understood dispersion of magnetic properties is reported, even within monodisperse samples of the canonical ferromagnetic 3d transition metals. We address this issue by investigating the magnetism of a large number of size- and shape-selected, individual nanoparticles of Fe, Co, and Ni using a unique set of complementary characterization techniques. At room temperature, only superparamagnetic behavior is observed in our experiments for all Ni nanoparticles within the investigated sizes, which range from 8 to 20 nm. However, Fe and Co nanoparticles can exist in two distinct magnetic states at any size in this range: (i) a superparamagnetic state, as expected from the bulk and surface anisotropies known for the respective materials and as observed for Ni, and (ii) a state with unexpected stable magnetization at room temperature. This striking state is assigned to significant modifications of the magnetic properties arising from metastable lattice defects in the core of the nanoparticles, as concluded by calculations and atomic structural characterization. Also related with the structural defects, we find that the magnetic state of Fe and Co nanoparticles can be tuned by thermal treatment enabling one to tailor their magnetic properties for applications. This paper demonstrates the importance of complementary single particle investigations for a better understanding of nanoparticle magnetism and for full exploration of their potential for applications.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000400665300002	Publication Date	2017-05-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	21	Open Access	OpenAccess
	Notes	We thank A. Weber, R. Schelldorfer, and J. Krbanjevic (Paul Scherrer Institut) for technical assistance. This paper was supported by the Swiss Nanoscience Institute, University of Basel. A.F.R. acknowledges support from the MICIIN “Ramón y Cajal” Programme. A.B. and J.V. acknowledge funding from the European Union under the European Research Council (ERC) Starting Grant No. 278510 VORTEX and under a contract for Integrated Infrastructure Initiative ESTEEM2 No. 312483. R.Y. and U.N. thank the Deutsche Forschungsgemeinschaft for financial support via Sonderforschungsbereich 1214. Part of this work was performed at the Surface/Interface: Microscopy (SIM) beamline of the Swiss Light Source, Paul Scherrer Institut, Villigen, Switzerland.			Approved	Most recent IF: 3.836
	Call Number	EMAT @ emat @ c:irua:143634UA @ admin @ c:irua:143634			Serial	4575
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	Author	Van der Donck, M.; Zarenia, M.; Peeters, F.M.
	Title	Excitons and trions in monolayer transition metal dichalcogenides : a comparative study between the multiband model and the quadratic single-band model			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	96	Issue	3	Pages	035131
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The electronic and structural properties of excitons and trions in monolayer transition metal dichalcogenides are investigated using both a multiband and a single- band model. In the multiband model we construct the excitonic Hamiltonian in the product base of the single-particle states at the conduction and valence band edges. We decouple the corresponding energy eigenvalue equation and solve the resulting differential equation self-consistently, using the finite element method (FEM), to determine the energy eigenvalues and the wave functions. As a comparison, we also consider the simple single-band model which is often used in numerical studies. We solve the energy eigenvalue equation using the FEM as well as with the stochastic variational method (SVM) in which a variational wave function is expanded in a basis of a large number of correlated Gaussians. We find good agreement between the results of both methods, as well as with other theoretical works for excitons, and we also compare with available experimental data. For trions the agreement between both methods is not as good due to our neglect of angular correlations when using the FEM. Finally, when comparing the two models, we see that the presence of the valence bands in the mutiband model leads to differences with the single- band model when (interband) interactions are strong.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000405706600005	Publication Date	2017-07-18
	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	50	Open Access
	Notes	; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:145209			Serial	4716
Permanent link to this record



	Author	Kong, X.; Li, L.; Leenaerts, O.; Liu, X.-J.; Peeters, F.M.
	Title	New group-V elemental bilayers : a tunable structure model with four-, six-, and eight-atom rings			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	96	Issue	3	Pages	035123
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Two-dimensional group-V elemental materials have attracted widespread attention due to their nonzero band gap while displaying high electron mobility. Using first-principles calculations, we propose a series of new elemental bilayers with group-V elements (Bi, Sb, As). Our study reveals the dynamical stability of four-, six-, and eight-atom ring structures, demonstrating their possible coexistence in such bilayer systems. The proposed structures for Sb and As are large-gap semiconductors that are potentially interesting for applications in future nanodevices. The Bi structures have nontrivial topological properties with a direct nontrivial band gap. The nontrivial gap is shown to arise from a band inversion at the Brillouin zone center due to the strong intrinsic spin-orbit coupling in Bi atoms. Moreover, we demonstrate the possibility of tuning the properties of these materials by enhancing the ratio of six-atom rings to four-and eight-atom rings, which results in wider nontrivial band gaps and lower formation energies.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000405363900005	Publication Date	2017-07-14
	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	14	Open Access
	Notes	; This work is supported by Ministry of Science and Technology of China (MOST) (Grant No. 2016YFA0301604), National Natural Science Foundation of China (NSFC) ( No. 11574008), the Thousand-Young-Talent Program of China, and the Fonds voor 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, and the National Supercomputing Center in Tianjin, funded by the Collaborative Innovation Center of Quantum Matter. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:144834			Serial	4721
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	Author	Ghorbanfekr-Kalashami, H.; Peeters, F.M.; Novoselov, K.S.; Neek-Amal, M.
	Title	Spatial design and control of graphene flake motion			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	96	Issue	6	Pages	060101
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000406860300001	Publication Date	2017-08-04
	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	3	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program. M.N.-A. was supported by Iran National Science Foundation (INSF). K.S.N. was supported by the EU Graphene Flagship Program, European Research Council Synergy Grant Hetero2D, the Royal Society, Engineering and Physical Research Council (UK), US Army Research Office. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:145166			Serial	4724
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	Author	Saberi-Pouya, S.; Vazifehshenas, T.; Salavati-fard, T.; Farmanbar, M.
	Title	Anisotropic hybrid excitation modes in monolayer and double-layer phosphorene on polar substrates			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	96	Issue	11	Pages	115402
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We investigate the anisotropic hybrid surface optical (SO) phonon-plasmon dispersion relations in monolayer and double-layer phosphorene systems located on the polar substrates, such as SiO2, h-BN, and Al2O3. We calculate these hybrid modes by using the dynamical dielectric function in the random phase approximation in which the electron-electron interaction and long-range electric field generated by the substrate SO phonons via Frohlich interaction are taken into account. In the long-wavelength limit, we obtain some analytical expressions for the hybrid SO phonon-plasmon dispersion relations which agree with those obtained from the loss function. Our results indicate a strong anisotropy in SO phonon-plasmon modes, which are stronger along the light-mass direction in our heterostructures. Furthermore, we find that the type of substrate has a significant effect on the dispersion relations of the coupled modes. Importantly, the hybrid excitations are apparently sensitive to the misalignment and separation between layers in double-layer phosphorene.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000408826200004	Publication Date	2017-09-01
	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	6	Open Access
	Notes	; ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:145665			Serial	4737
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	Author	Zebrowski, D.P.; Peeters, F.M.; Szafran, B.
	Title	Double quantum dots defined in bilayer graphene			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	96	Issue	3	Pages	035434
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Artificial molecular states of double quantum dots defined in bilayer graphene are studied with the atomistic tight-binding method and its low-energy continuum approximation. We indicate that the extended electron wave functions have opposite parities on sublattices of the layers and that the ground-state wave-function components change from bonding to antibonding with the interdot distance. In the weak-coupling limit, the one most relevant for quantum dots defined electrostatically, the signatures of the interdot coupling include, for the two-electron ground state, formation of states with symmetric or antisymmetric spatial wave functions split by the exchange energy. In the high-energy part of the spectrum the states with both electrons in the same dot are found with the splitting of energy levels corresponding to simultaneous tunneling of the electron pair from one dot to the other.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000406284200005	Publication Date	2017-07-26
	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	6	Open Access
	Notes	; ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:145758			Serial	4739
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	Author	Bekaert, J.; Aperis, A.; Partoens, B.; Oppeneer, P.M.; Milošević, M.V.
	Title	Evolution of multigap superconductivity in the atomically thin limit : strain-enhanced three-gap superconductivity in monolayer MgB₂			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	96	Issue	9	Pages	094510
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Starting from first principles, we show the formation and evolution of superconducting gaps in MgB2 at its ultrathin limit. Atomically thin MgB2 is distinctly different from bulk MgB2 in that surface states become comparable in electronic density to the bulklike sigma and pi bands. Combining the ab initio electron-phonon coupling with the anisotropic Eliashberg equations, we showthat monolayer MgB2 develops three distinct superconducting gaps, on completely separate parts of the Fermi surface due to the emergent surface contribution. These gaps hybridize nontrivially with every extra monolayer added to the film owing to the opening of additional coupling channels. Furthermore, we reveal that the three-gap superconductivity in monolayer MgB2 is robust over the entire temperature range that stretches up to a considerably high critical temperature of 20 K. The latter can be boosted to >50K under biaxial tensile strain of similar to 4%, which is an enhancement that is stronger than in any other graphene-related superconductor known to date.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000410166800008	Publication Date	2017-09-11
	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	56	Open Access
	Notes	; This work was supported by TOPBOF-UAntwerp, Research Foundation-Flanders (FWO), the Swedish Research Council (VR), and the Rontgen-Angstrom Cluster. The first-principles calculations have been carried out on the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Centre (VSC), supported financially by the Hercules Foundation and the Flemish Government (EWI Department). Eliashberg theory calculations were supported through the Swedish National Infrastructure for Computing (SNIC). ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:145623			Serial	4741
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	Author	Xiao, Y.M.; Xu, W.; Peeters, F.M.; Van Duppen, B.
	Title	Multicomponent plasmons in monolayer MoS₂ with circularly polarized optical pumping			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	96	Issue	8	Pages	085405
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	By making use of circularly polarized light and electrostatic gating, monolayer molybdenum disulfide (ML – MoS2) can form a platform supporting multiple types of charge carriers. They can be discriminated by their spin, valley index, or whether they are electrons or holes. We investigate the collective properties of those charge carriers and are able to identify distinct plasmon modes. We analyze the corresponding dispersion relation, lifetime, and oscillator strength, and calculate the phase relation between the oscillations in the different components of the plasmon modes. All platforms in ML-MoS2 support a long-wavelength root q plasmon branch at zero kelvins. In addition to this, for an n-component system, n-1 distinct plasmon modes appear as acoustic modes with linear dispersion in the long-wavelength limit. These modes correspond to out-of-phase oscillations in the different fermion liquids and have, although being damped, a relatively long lifetime. Additionally, we also find distinct modes at large wave vectors that are more strongly damped by intraband processes.
	Address
	Corporate Author				Thesis
	Publisher	American Physical Society	Place of Publication	New York, N.Y	Editor
	Language		Wos	000406861600001	Publication Date	2017-08-04
	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	2	Open Access
	Notes	; Y.M.X. acknowledges financial support from the China Scholarship Council (CSC). B.V.D. is supported by the Flemish Science Foundation (FWO-Vl) through a postdoctoral fellowship. This work was also supported by the National Natural Science Foundation of China (Grants No. 11574319 and No. 11304272), the Ministry of Science and Technology of China (Grant No. 2011YQ130018), the Department of Science and Technology of Yunnan Province, the Applied Basic Research Foundation of Yunnan Province (2013FD003), and the Chinese Academy of Sciences. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ lucian @ c:irua:145729			Serial	4745
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