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	Author	Singh, S.K.; Neek-Amal, M.; Costamagna, S.; Peeters, F.M.
	Title	Rippling, buckling, and melting of single- and multilayer MoS₂			Type	A1 Journal article
	Year	2015	Publication	Physical Review B	Abbreviated Journal	Phys Rev B
	Volume	91	Issue	91	Pages	014101
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Large-scale atomistic simulations using the reactive empirical bond order force field approach is implemented to investigate thermal and mechanical properties of single-layer (SL) and multilayer (ML) molybdenum disulfide (MoS2). The amplitude of the intrinsic ripples of SL MoS2 are found to be smaller than those exhibited by graphene (GE). Furthermore, because of the van der Waals interaction between layers, the out-of-plane thermal fluctuations of ML MoS2 decreases rapidly with increasing number of layers. This trend is confirmed by the buckling transition due to uniaxial stress which occurs for a significantly larger applied tension as compared to graphene. For SL MoS2, the melting temperature is estimated to be 3700 K which occurs through dimerization followed by the formation of small molecules consisting of two to five atoms. When different types of vacancies are inserted in the SL MoS2 it results in a decrease of both the melting temperature as well as the stiffness.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lancaster, Pa	Editor
	Language		Wos	000347921300001	Publication Date	2015-01-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	40	Open Access
	Notes	; This work is supported by the ESF-Eurographene project CONGRAN, the Flemish Science Foundation (FWO-VI), and the Methusalem Foundation of the Flemish Government. We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. We would like to thanks Prof. Douglas E. Spearot [26] for giving us the implemented parameters of Mo-S in LAMMPS. ;			Approved	Most recent IF: 3.836; 2015 IF: 3.736
	Call Number	c:irua:123834			Serial	2909
Permanent link to this record



	Author	da Costa, D.R.; Zarenia, M.; Chaves, A.; Farias, G.A.; Peeters, F.M.
	Title	Magnetic field dependence of energy levels in biased bilayer graphene quantum dots			Type	A1 Journal article
	Year	2016	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	93	Issue	93	Pages	085401
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Using the tight-binding approach, we study the influence of a perpendicular magnetic field on the energy levels of hexagonal, triangular, and circular bilayer graphene (BLG) quantum dots (QDs) with zigzag and armchair edges. We obtain the energy levels for AB (Bernal)-stacked BLG QDs in both the absence and the presence of a perpendicular electric field (i.e., biased BLG QDs). We find different regions in the spectrum of biased QDs with respect to the crossing point between the lowest-electron and -hole Landau levels of a biased BLG sheet. Those different regions correspond to electron states that are localized at the center, edge, or corner of the BLG QD. Quantum Hall corner states are found to be absent in circular BLG QDs. The spatial symmetry of the carrier density distribution is related to the symmetry of the confinement potential, the position of zigzag edges, and the presence or absence of interlayer inversion symmetry.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000369402400008	Publication Date	2016-02-01
	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	22	Open Access
	Notes	; This work was financially supported by CNPq, under Contract No. NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES Foundation under the Process No. BEX 7178/13-1, the Flemish Science Foundation (FWO-Vl), the Bilateral programme between CNPq and FWO-Vl, and the Brazilian Program Science Without Borders (CsF). ;			Approved	Most recent IF: 3.836
	Call Number	c:irua:131623			Serial	4038
Permanent link to this record



	Author	Bekaert, J.; Vercauteren, S.; Aperis, A.; Komendová, L.; Prozorov, R.; Partoens, B.; Milošević, M.V.
	Title	Anisotropic type-I superconductivity and anomalous superfluid density in OsB2			Type	A1 Journal article
	Year	2016	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	94	Issue	94	Pages	144506
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We present a microscopic study of superconductivity in OsB2 , and discuss the origin and characteristic length scales of the superconducting state. From first-principles we show that OsB2 is characterized by three different Fermi sheets, and we prove that this fermiology complies with recent quantum-oscillation experiments. Using the found microscopic properties, and experimental data from the literature, we employ Ginzburg-Landau relations to reveal that OsB2 is a distinctly type-I superconductor with a very low Ginzburg-Landau parameter κ—a rare property among compound materials. We show that the found coherence length and penetration depth corroborate the measured thermodynamic critical field. Moreover, our calculation of the superconducting gap structure using anisotropic Eliashberg theory and ab initio calculated electron-phonon interaction as input reveals a single but anisotropic gap. The calculated gap spectrum is shown to give an excellent account for the unconventional behavior of the superfluid density of OsB2 measured in experiments as a function of temperature. This reveals that gap anisotropy can explain such behavior, observed in several compounds, which was previously attributed solely to a two-gap nature of superconductivity.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000385622500009	Publication Date	2016-10-12
	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	19	Open Access
	Notes	Fonds Wetenschappelijk Onderzoek; European Cooperation in Science and Technology, MP1201 ; Vetenskapsrådet;			Approved	Most recent IF: 3.836
	Call Number	CMT @ cmt @ c:irua:139020			Serial	4338
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	Author	Vagov, A.; Shanenko, A.A.; Milošević, M.V.; Axt, V.M.; Vinokur, V.M.; Aguiar, J.A.; Peeters, F.M.
	Title	Superconductivity between standard types: Multiband versus single-band materials			Type	A1 Journal article
	Year	2016	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	93	Issue	93	Pages	174503
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000375527500001	Publication Date	2016-05-06
	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	37	Open Access
	Notes	Conselho Nacional de Desenvolvimento Científico e Tecnológico, 307552/2012-8 141911/2012-3 ; Fundação de Amparo à Ciência e Tecnologia do Estado de Pernambuco, APQ-0589-1.05/08 ; U.S. Department of Energy;			Approved	Most recent IF: 3.836
	Call Number	CMT @ cmt @ c:irua:141732			Serial	4480
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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	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	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	Mulkers, J.; Van Waeyenberge, B.; Milošević, M.V.
	Title	Tunable Snell's law for spin waves in heterochiral magnetic films			Type	A1 Journal article
	Year	2018	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	97	Issue	10	Pages	104422
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Thin ferromagnetic films with an interfacially induced DMI exhibit nontrivial asymmetric dispersion relations that lead to unique and useful magnonic properties. Here we derive an analytical expression for the magnon propagation angle within the micromagnetic framework and show how the dispersion relation can be approximated with a comprehensible geometrical interpretation in the k space of the propagation of spin waves. We further explore the refraction of spin waves at DMI interfaces in heterochiral magnetic films, after deriving a generalized Snell's law tunable by an in-plane magnetic field, that yields analytical expressions for critical incident angles. The found asymmetric Brewster angles at interfaces of regions with different DMI strengths, adjustable by magnetic field, support the conclusion that heterochiral ferromagnetic structures are an ideal platform for versatile spin-wave guides.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000428238600006	Publication Date	2018-03-26
	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	20	Open Access
	Notes	This work was supported by the Research Foundation- Flanders (FWO-Vlaanderen) through Project No. G098917N.			Approved	Most recent IF: 3.836
	Call Number	CMT @ cmt @c:irua:150118UA @ admin @ c:irua:150118			Serial	4915
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	Author	Cavalcante, L.S.R.; Chaves, A.; Van Duppen, B.; Peeters, F.M.; Reichman, D.R.
	Title	Electrostatics of electron-hole interactions in van der Waals heterostructures			Type	A1 Journal article
	Year	2018	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	97	Issue	12	Pages	125427
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The role of dielectric screening of electron-hole interaction in van der Waals heterostructures is theoretically investigated. A comparison between models available in the literature for describing these interactions is made and the limitations of these approaches are discussed. A simple numerical solution of Poisson's equation for a stack of dielectric slabs based on a transfer matrix method is developed, enabling the calculation of the electron-hole interaction potential at very low computational cost and with reasonable accuracy. Using different potential models, direct and indirect exciton binding energies in these systems are calculated within Wannier-Mott theory, and a comparison of theoretical results with recent experiments on excitons in two-dimensional materials is discussed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000427983700007	Publication Date	2018-03-21
	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	22	Open Access
	Notes	Discussions with A. Chernikov and A. Raja are gratefully acknowledged. This work has been financially supported by CNPq, through the PRONEX/FUNCAP, PQ, and Science Without Borders programs, and the FWO-CNPq bilateral program between Brazil and Flanders. B.V.D. acknowledges support from the Flemish Science Foundation (FWO-Vl) through a postdoctoral fellowship. D.R.R. was supported by NSF CHE-1464802.			Approved	Most recent IF: 3.836
	Call Number	CMT @ cmt @c:irua:150835UA @ admin @ c:irua:150835			Serial	4953
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	Author	Bacaksiz, C.; Šabani, D.; Menezes, R.M.; Milošević, M.V.
	Title	Distinctive magnetic properties of CrI3 and CrBr3 monolayers caused by spin-orbit coupling			Type	A1 Journal article
	Year	2021	Publication	Physical Review B	Abbreviated Journal	Phys Rev B
	Volume	103	Issue	12	Pages	125418
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	After the discovery of magnetism in monolayer CrI3, the magnetic properties of different 2D materials from the chromium-trihalide family are intuitively assumed to be similar, yielding magnetic anisotropy from the spin-orbit coupling on halide ligands. Here we reveal significant differences between the CrI3 and CrBr3 magnetic monolayers in their magnetic anisotropy, resulting Curie temperature, hysteresis in external magnetic field, and evolution of magnetism with strain, all predominantly attributed to distinctly different interplay of atomic contributions to spin-orbit coupling in two materials.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000646179300003	Publication Date	2021-03-17
	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	18	Open Access	OpenAccess
	Notes	Fonds Wetenschappelijk Onderzoek; Universiteit Antwerpen;			Approved	Most recent IF: 3.836
	Call Number	CMT @ cmt @c:irua:177506			Serial	6756
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	Author	Claes, J.; Partoens, B.; Lamoen, D.
	Title	Decoupled DFT-1/2 method for defect excitation energies			Type	A1 Journal Article
	Year	2023	Publication	Physical Review B	Abbreviated Journal	Phys. Rev. B
	Volume	108	Issue	12	Pages	125306
	Keywords	A1 Journal Article; Condensed Matter Theory (CMT) ;
	Abstract	The DFT-1/2 method is a band-gap correction with GW precision at a density functional theory (DFT) computational cost. The method was also extended to correct the gap between defect levels, allowing for the calculation of optical transitions. However, this method fails when the atomic character of the occupied and unoccupied defect levels is similar as we illustrate by two examples, the tetrahedral hydrogen interstitial and the negatively charged vacancy in diamond. We solve this problem by decoupling the effect of the occupied and unoccupied defect levels and call this the decoupled DFT-1/2 method for defects.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	001089302800003	Publication Date	2023-09-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9950	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor	3.7	Times cited		Open Access	Not_Open_Access
	Notes	This work was supported by the FWO (Research Foundation-Flanders), Project No. G0D1721N. This work was performed in part using HPC resources from the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government department EWI (Economie, Wetenschap & Innovatie).			Approved	Most recent IF: 3.7; 2023 IF: 3.836
	Call Number	CMT @ cmt @c:irua:201287			Serial	8976
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	Author	N. Gauquelin, E. Benckiser, M. K. Kinyanjui, M. Wu, Y. Lu, G. Christiani, G. Logvenov, H.-U. Habermeier, U. Kaiser, B. Keimer, and G. A. Botton
	Title	Atomically resolved EELS mapping of the interfacial structure of epitaxially strained LaNiO3/LaAlO3 superlattices			Type	A1 Journal Article
	Year	2014	Publication	Physical Review B	Abbreviated Journal
	Volume	90	Issue		Pages	195140
	Keywords	A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
	Abstract	The interfacial atomic structure of a metallic LaNiO3/LaAlO3 superlattice grown on a LaSrAlO4 substrate was investigated using a combination of atomically resolved electron energy loss spectroscopy (EELS) at the Al K, Al L2,3, Sr L2,3, Ni L2,3, La M4,5, and O K edges as well as hybridization mapping of selected features of the O K-edge fine structure.We observe an additional La1−xSrxAl1−yNiyO3 layer at the substrate-superlattice interface, possibly linked to diffusion of Al and Sr into the growing film or a surface reconstruction due to Sr segregation. The roughness of the LaNiO3/LaAlO3 interfaces is found to be on average around one pseudocubic unit cell. The O K-edge EELS spectra revealed reduced spectral weight of the prepeak derived from Ni-O hybridized states in the LaNiO3 layers. We rule out oxygen nonstoichiometry of the LaNiO3 layers and discuss changes in the Ni-O hybridization due to heterostructuring as possible origin.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000345467000003	Publication Date	2014-11-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links
	Impact Factor		Times cited	17	Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	EMAT @ emat @			Serial	4544
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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	Tsirlin, A.A.; Rousochatzakis, I.; Filimonov, D.; Batuk, D.; Frontzek, M.; Abakumov, A.M.
	Title	Spin-reorientation transitions in the Cairo pentagonal magnet Bi4Fe5O13F			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	96	Issue	9	Pages	094420
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	We show that interlayer spins play a dual role in the Cairo pentagonal magnet Bi4Fe5O13F, on one hand mediating the three-dimensional magnetic order, and on the other driving spin-reorientation transitions both within and between the planes. The corresponding sequence of magnetic orders unraveled by neutron diffraction and Mossbauer spectroscopy features two orthogonal magnetic structures described by opposite local vector chiralities, and an intermediate, partly disordered phase with nearly collinear spins. A similar collinear phase has been predicted theoretically to be stabilized by quantum fluctuations, but Bi4Fe5O13F is very far from the relevant parameter regime. While the observed in-plane reorientation cannot be explained by any standard frustration mechanism, our ab initio band-structure calculations reveal strong single-ion anisotropy of the interlayer Fe3+ spins that turns out to be instrumental in controlling the local vector chirality and the associated interlayer order.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000411161700002	Publication Date	2017-09-19
	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	7	Open Access	OpenAccess
	Notes	We are grateful to J.-M. Perez-Mato and Dmitry Khalyavin for valuable discussions on the magnetic structures and symmetries. D.F. and A.A. are grateful to the Russian Science Foundation (Grant No. 14-13-00680) for support. A.T. was supported by the Federal Ministry for Education and Research through the Sofja Kovalevskaya Award of the Alexander von Humboldt Foundation. This work is based on experiments performed at the Swiss spallation neutron source SINQ, Paul Scherrer Institut, Villigen, Switzerland.			Approved	Most recent IF: 3.836
	Call Number	EMAT @ emat @c:irua:146748			Serial	4774
Permanent link to this record



	Author	Savchenko, T.M.; Buzzi, M.; Howald, L.; Ruta, S.; Vijayakumar, J.; Timm, M.; Bracher, D.; Saha, S.; Derlet, P.M.; Béché, A.; Verbeeck, J.; Chantrell, R.W.; Vaz, C.A.F.; Nolting, F.; Kleibert, A.
	Title	Single femtosecond laser pulse excitation of individual cobalt nanoparticles			Type	A1 Journal article
	Year	2020	Publication	Physical Review B	Abbreviated Journal	Phys Rev B
	Volume	102	Issue	20	Pages	205418
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Laser-induced manipulation of magnetism at the nanoscale is a rapidly growing research topic with potential for applications in spintronics. In this work, we address the role of the scattering cross section, thermal effects, and laser fluence on the magnetic, structural, and chemical stability of individual magnetic nanoparticles excited by single femtosecond laser pulses. We find that the energy transfer from the fs laser pulse to the nanoparticles is limited by the Rayleigh scattering cross section, which in combination with the light absorption of the supporting substrate and protective layers determines the increase in the nanoparticle temperature. We investigate individual Co nanoparticles (8 to 20 nm in size) as a prototypical model system, using x-ray photoemission electron microscopy and scanning electron microscopy upon excitation with single femtosecond laser pulses of varying intensity and polarization. In agreement with calculations, we find no deterministic or stochastic reversal of the magnetization in the nanoparticles up to intensities where ultrafast demagnetization or all-optical switching is typically reported in thin films. Instead, at higher fluences, the laser pulse excitation leads to photo-chemical reactions of the nanoparticles with the protective layer, which results in an irreversible change in the magnetic properties. Based on our findings, we discuss the conditions required for achieving laser-induced switching in isolated nanomagnets.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000589602000005	Publication Date	2020-11-16
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9950	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor	3.7	Times cited	1	Open Access	OpenAccess
	Notes	This work received funding by the Swiss National Foundation (SNF) (Grants No. 200021160186 and No. 2002153540), the Swiss Nanoscience Institute (SNI) (Grant No. SNI P1502), the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No. 737093 (FEMTOTERABYTE), and the COST Action CA17123 (MAGNETOFON). Part of this work was performed at the SIM beamline of the Swiss Light Source (SLS), Paul Scherrer Institut, Villigen, Switzerland. Part of the simulations were undertaken on the VIKING cluster, which is a high-performance compute facility provided by the University of York. We kindly acknowledge Anja Weber from PSI for preparation of substrates with marker structures. A.B. and Jo Verbeeck acknowledge funding through FWO Project No. G093417N (“Compressed sensing enabling low dose imaging in transmission electron microscopy”) from the Flanders Research Fund. Jo Verbeeck acknowledges funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No. 823717 – ESTEEM3. S.S. acknowledges ETH Zurich Post-Doctoral fellowship and Marie Curie actions for people COFUND program.; esteem3JRA; esteem3reported			Approved	Most recent IF: 3.7; 2020 IF: 3.836
	Call Number	EMAT @ emat @c:irua:174273			Serial	6669
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	Author	Bercx, M.; Partoens, B.; Lamoen, D.
	Title	Quantitative modeling of secondary electron emission from slow-ion bombardment on semiconductors			Type	A1 Journal article
	Year	2019	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	99	Issue	8	Pages	085413
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	When slow ions incident on a surface are neutralized, the excess potential energy is passed on to an electron inside the surface, leading to emission of secondary electrons. The microscopic description of this process, as well as the calculation of the secondary electron yield, is a challenging problem due to its complexity as well as its sensitivity to surface properties. One of the first quantitative descriptions was articulated in the 1950s by Hagstrum, who based his calculation on a parametrization of the density of states of the material. In this paper, we present a model for calculating the secondary electron yield, derived from Hagstrum’s initial approach. We use first-principles density functional theory calculations to acquire the necessary input and introduce the concept of electron cascades to Hagstrum’s model in order to improve the calculated spectra, as well as remove its reliance on fitting parameters. We apply our model to He+ and Ne+ ions incident on Ge(111) and Si(111) and obtain yield spectra that match closely to the experimental results of Hagstrum.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000458367800010	Publication Date	2019-02-11
	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	5	Open Access	OpenAccess
	Notes	We would like to thank Prof. D. Depla for the useful discussions on the secondary electron yield. Furthermore, we acknowledge financial support of FWO-Vlaanderen through project G.0216.14N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWOVlaanderen and the Flemish Government-department EWI.			Approved	Most recent IF: 3.836
	Call Number	EMAT @ emat @UA @ admin @ c:irua:157174			Serial	5154
Permanent link to this record



	Author	Mirzakhani, M.; Zarenia, M.; Vasilopoulos, P.; Peeters, F.M.
	Title	Electrostatically confined trilayer graphene quantum dots			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal
	Volume	95	Issue	15	Pages	155434
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Electrically gating of trilayer graphene (TLG) opens a band gap offering the possibility to electrically engineer TLG quantum dots. We study the energy levels of such quantum dots and investigate their dependence on a perpendicular magnetic field B and different types of stacking of the graphene layers. The dots are modeled as circular and confined by a truncated parabolic potential which can be realized by nanostructured gates or position-dependent doping. The energy spectra exhibit the intervalley symmetry E-K(e) (m) = -E (h)(K') (m) for the electron (e) and hole (h) states, where m is the angular momentum quantum number and K and K' label the two valleys. The electron and hole spectra for B = 0 are twofold degenerate due to the intervalley symmetry E-K (m) = E-K' [-(m + 1)]. For both ABC [alpha = 1.5 (1.2) for large (small) R] and ABA (alpha = 1) stackings, the lowest-energy levels show approximately a R-alpha dependence on the dot radius R in contrast with the 1/R-3 one for ABC-stacked dots with infinite-mass boundary. As functions of the field B, the oscillator strengths for dipole-allowed transitions differ drastically for the two types of stackings.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000399797200003	Publication Date	2017-04-22
	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		Times cited	6	Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:152652			Serial	7878
Permanent link to this record



	Author	Shayeganfar, F.; Vasu, K.S.; Nair, R.R.; Peeters, F.M.; Neek-Amal, M.
	Title	Monolayer alkali and transition-metal monoxides : MgO, CaO, MnO, and NiO			Type	A1 Journal article
	Year	2017	Publication	Physical review B	Abbreviated Journal
	Volume	95	Issue	14	Pages	144109
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Two-dimensional crystals with strong interactions between layers has attracted increasing attention in recent years in a variety of fields. In particular, the growth of a single layer of oxide materials (e.g., MgO, CaO, NiO, and MnO) over metallic substrates were found to display different physical properties than their bulk. In this study, we report on the physical properties of a single layer of metallic oxide materials and compare their properties with their bulk and other two-dimensional (2D) crystals. We found that the planar structure of metallic monoxides are unstable whereas the buckled structures are thermodynamically stable. Also, the 2D-MnO and NiO exhibit different magnetic (ferromagnetic) and optical properties than their bulk, whereas band-gap energy and linear stiffness are found to be decreasing from NiO to MgO. Our findings provide insight into oxide thin-film technology applications.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000399792400001	Publication Date	2017-04-20
	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		Times cited	21	Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:152654			Serial	8278
Permanent link to this record



	Author	Saberi-Pouya, S.; Zarenia, M.; Vazifehshenas, T.; Peeters, F.M.
	Title	Anisotropic charge density wave in electron-hole double monolayers : applied to phosphorene			Type	A1 Journal article
	Year	2018	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	98	Issue	24	Pages	245115
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The possibility of an inhomogeneous charge density wave phase is investigated in a system of two coupled electron and hole monolayers separated by a hexagonal boron nitride insulating layer. The charge-density-wave state is induced through the assumption of negative compressibility of electron/hole gases in a Coulomb drag configuration between the electron and hole sheets. Under equilibrium conditions, we derive analytical expressions for the density oscillation along the zigzag and armchair directions. We find that the density modulation not only depends on the sign of the compressibility but also on the anisotropy of the low-energy bands. Our results are applicable to any two-dimensional system with anisotropic parabolic bands, characterized by different effective masses. For equal effective masses, i.e., isotropic energy bands, our results agree with Hroblak et al. [Phys. Rev. B 96, 075422 (2017)]. Our numerical results are applied to phosphorene.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000452995600001	Publication Date	2018-12-12
	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	3.836	Times cited		Open Access
	Notes	; This work was partially supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program of the Flemish government and Iran Science Elites Federation. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ admin @ c:irua:156233			Serial	5195
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	Author	Sanchez-Barriga, J.; Aguilera, I.; Yashina, L., V; Tsukanova, D.Y.; Freyse, F.; Chaika, A.N.; Callaert, C.; Abakumov, A.M.; Hadermann, J.; Varykhalov, A.; Rienks, E.D.L.; Bihlmayer, G.; Blugel, S.; Rader, O.
	Title	Anomalous behavior of the electronic structure of (Bi_1-xIn_x)₂Se₃across the quantum phase transition from topological to trivial insulator			Type	A1 Journal article
	Year	2018	Publication	Physical review B	Abbreviated Journal
	Volume	98	Issue	23	Pages	235110
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Using spin- and angle-resolved photoemission spectroscopy and relativistic many-body calculations, we investigate the evolution of the electronic structure of (Bi1-xInx)(2)Se-3)(2)Se-3 bulk single crystals around the critical point of the trivial to topological insulator quantum-phase transition. By increasing x, we observe how a surface gap opens at the Dirac point of the initially gapless topological surface state of Bi2Se3, leading to the existence of massive fermions. The surface gap monotonically increases for a wide range of x values across the topological and trivial sides of the quantum-phase transition. By means of photon-energy-dependent measurements, we demonstrate that the gapped surface state survives the inversion of the bulk bands which occurs at a critical point near x = 0.055. The surface state exhibits a nonzero in-plane spin polarization which decays exponentially with increasing x, and which persists in both the topological and trivial insulator phases. Our calculations reveal qualitative agreement with the experimental results all across the quantum-phase transition upon the systematic variation of the spin-orbit coupling strength. A non-time-reversal symmetry-breaking mechanism of bulk-mediated scattering processes that increase with decreasing spin-orbit coupling strength is proposed as explanation.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000452322800003	Publication Date	2018-12-05
	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		Times cited		Open Access
	Notes				Approved	no
	Call Number	UA @ admin @ c:irua:156240			Serial	7462
Permanent link to this record



	Author	Van der Donck, M.; Peeters, F.M.
	Title	Excitonic complexes in anisotropic atomically thin two-dimensional materials : black phosphorus and TiS₃			Type	A1 Journal article
	Year	2018	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	98	Issue	23	Pages	235401
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The effect of anisotropy in the energy spectrum on the binding energy and structural properties of excitons, trions, and biexcitons is investigated. To this end we employ the stochastic variational method with a correlated Gaussian basis. We present results for the binding energy of different excitonic complexes in black phosphorus (bP) and TiS3 and compare them with recent results in the literature when available, for which we find good agreement. The binding energies of excitonic complexes in bP are larger than those in TiS3. We calculate the different average interparticle distances in bP and TiS3 and show that excitonic complexes in bP are strongly anisotropic whereas in TiS3 they are almost isotropic, even though the constituent particles have an anisotropic energy spectrum. This is also confirmed by the correlation functions.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000452003400009	Publication Date	2018-12-03
	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	10	Open Access
	Notes	; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD and by the FLAG-ERA project TRANS-2D-TMD. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ admin @ c:irua:156247			Serial	5211
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	Author	Das, S.; Rata, A.D.; Maznichenko, I., V; Agrestini, I.S.; Pippel, E.; Gauquelin, N.; Verbeeck, J.; Chen, K.; Valvidares, S.M.; Vasili, H.B.; Herrero-Martin, J.; Pellegrin, E.; Nenkov, K.; Herklotz, A.; Ernst, A.; Mertig, I.; Hu, Z.; Doerr, K.
	Title	Low-field switching of noncollinear spin texture at La_0.7Sr_0.3MnO₃-SrRuO₃interfaces			Type	A1 Journal article
	Year	2019	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	99	Issue	2	Pages	024416
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Interfaces of ferroic oxides can show complex magnetic textures which have strong impact on spintronics devices. This has been demonstrated recently for interfaces with insulating antiferromagnets such as BiFeO3. Here, noncollinear spin textures which can be switched in very low magnetic field are reported for conducting ferromagnetic bilayers of La0.7Sr0.3MnO3-SrRuO3 (LSMO-SRO). The magnetic order and switching are fundamentally different for bilayers coherently grown in reversed stacking sequence. The SRO top layer forms a persistent exchange spring which is antiferromagnetically coupled to LSMO and drives switching in low fields of a few milliteslas. Density functional theory reveals the crucial impact of the interface termination on the strength of Mn-Ru exchange coupling across the interface. The observation of an exchange spring agrees with ultrastrong coupling for the MnO2/SrO termination. Our results demonstrate low-field switching of noncollinear spin textures at an interface between conducting oxides, opening a pathway for manipulating and utilizing electron transport phenomena in controlled spin textures at oxide interfaces.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000455821400005	Publication Date	2019-01-15
	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	OpenAccess
	Notes	; The research in Halle was supported by Deutsche Forschungsgemeinschaft (DFG), SFB 762 Functional Oxide Interfaces (Projects No. A9 and No. B1). K.C. benefited from support of the DFG (Project 600575). Discussions with M. Trassin, M. Ziese, H. M. Christen, E.-J. Guo, F. Grcondciel, M. Bibes, and H. N. Lee are gratefully acknowledged. N. G. and J. V. acknowledge funding under the GOA project “Solarpaint” of the University of Antwerp. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ admin @ c:irua:156717			Serial	5255
Permanent link to this record



	Author	Dharma-Wardana, M.W.C.; Neilson, D.; Peeters, F.M.
	Title	Correlation functions in electron-electron and electron-hole double quantum wells : temperature, density, and barrier-width dependence			Type	A1 Journal article
	Year	2019	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	99	Issue	3	Pages	035303
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The classical-map hypernetted-chain (CHNC) scheme, developed for treating fermion fluids at strong coupling and at finite temperatures, is applied to electron-electron and electron-hole double quantum wells. The pair-distribution functions and the local field factors needed in linear-response theory are determined for a range of temperatures, carrier densities, and barrier widths typical for experimental double-quantum-well systems in GaAs-GaAlAs. For electron-hole double quantum wells, a large enhancement in the pair-distribution functions is found for small carrier separations. The CHNC equations for electron-hole systems no longer hold at low densities where bound-state formation occurs.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000455163800004	Publication Date	2019-01-08
	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	; This work was partially supported by the Flemish Science Foundation (FWO-Vl). M.W.C.D.-W. acknowledges with thanks the hospitality and stimulating atmosphere of the Condensed Matter Theory group at the University of Antwerp. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ admin @ c:irua:156734			Serial	5201
Permanent link to this record



	Author	Kuo, C.-T.; Lin, S.-C.; Ghiringhelli, G.; Peng, Y.; De Luca, G.M.; Di Castro, D.; Betto, D.; Gehlmann, M.; Wijnands, T.; Huijben, M.; Meyer-Ilse, J.; Gullikson, E.; Kortright, J.B.; Vailionis, A.; Gauquelin, N.; Verbeeck, J.; Gerber, T.; Balestrino, G.; Brookes, N.B.; Braicovich, L.; Fadley, C.S.
	Title	Depth-resolved resonant inelastic x-ray scattering at a superconductor/half-metallic-ferromagnet interface through standing wave excitation			Type	A1 Journal article
	Year	2018	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	98	Issue	23	Pages	235146
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	We demonstrate that combining standing wave (SW) excitation with resonant inelastic x-ray scattering (RIXS) can lead to depth resolution and interface sensitivity for studying orbital and magnetic excitations in correlated oxide heterostructures. SW-RIXS has been applied to multilayer heterostructures consisting of a superconductor La1.85Sr0.15CuO4 (LSCO) and a half-metallic ferromagnet La0.67Sr0.33MnO3 (LSMO). Easily observable SW effects on the RIXS excitations were found in these LSCO/LSMO multilayers. In addition, we observe different depth distribution of the RIXS excitations. The magnetic excitations are found to arise from the LSCO/LSMO interfaces, and there is also a suggestion that one of the dd excitations comes from the interfaces. SW-RIXS measurements of correlated-oxide and other multilayer heterostructures should provide unique layer-resolved insights concerning their orbital and magnetic excitations, as well as a challenge for RIXS theory to specifically deal with interface effects.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000454160800004	Publication Date	2018-12-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2469-9969; 2469-9950	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	5	Open Access
	Notes	J.V. and N.G. acknowledge ˝ funding through the GOA project “Solarpaint” of the University of Antwerp. The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government.			Approved	Most recent IF: 3.836
	Call Number	UA @ admin @ c:irua:156784			Serial	5363
Permanent link to this record



	Author	Wang, W.; Van Duppen, B.; Peeters, F.M.
	Title	Intense-terahertz-laser-modulated magnetopolaron effect on shallow-donor states in the presence of magnetic field in the Voigt configuration			Type	A1 Journal article
	Year	2019	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	99	Issue	1	Pages	014114
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The laser-modulated magnetopolaron effect on shallow donors in semiconductors is investigated in the presence of a magnetic field in the Voigt configuration. A nonperturbative approach is used to describe the electron-photon interaction by including the radiation field in an exact way via a laser-dressed interaction potential. Through a variational approach we evaluate the donor binding energy. We find that the interaction strength of the laser-dressed Coulomb potential in the z direction cannot only be enhanced but also weakened by the radiation field, while that in the x-y plane is only weakened. In this way, the binding energy of the states with odd z parity, like 2p(z) can be decreased or increased with respect to its static binding energy by the radiation field, while that of the other states can be only decreased. Furthermore, all binding energies become insensitive to the magnetic field if the radiation field is strong. The magnetopolaron effect on these energies is studied within second-order time-dependent perturbation theory. In the nonresonant region, a laser-modulated magnetopolaron correction, including the effect of single-photon processes, is observed. In the resonant region, a laser-modulated magnetopolaron effect, accompanied by the emission and absorption of a single photon, is found. Moreover, the 1s -> 2p(+) transition, accompanied by the emission of a single photon, is tuned by the radiation field into resonance with the longitudinal-optical phonon branch. This is electrically analogous to the magnetopolaron effect, and therefore we name it the dynamical magnetopolaron effect. Finally, by changing the frequency of the radiation field, these interesting effects can be tuned to be far away from the reststrahlen band and, therefore, can be detected experimentally. This in turn provides a direct measure of the electron-phonon interaction.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000457057500001	Publication Date	2019-01-29
	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	; This work was supported by National Natural Science Foundation of China (Grants No. 11404214, No. 11455015, and No. 61504016) and the China Scholarship Council (CSC), and Science and Technology Research Foundation of Jiangxi Provincial Education Department (Grants No. GJJ161062 and No. GJJ180868). B.V.D. was supported by the Research Foundation – Flanders (FWO-Vl) through a postdoctoral fellowship. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ admin @ c:irua:157555			Serial	5218
Permanent link to this record



	Author	Behera, B.C.; Jana, S.; Bhat, S.G.; Gauquelin, N.; Tripathy, G.; Kumar, P.S.A.; Samal, D.
	Title	Evidence for exchange bias coupling at the perovskite/brownmillerite interface in spontaneously stabilized SrCoO_3-\delta/SrCoO_2.5 bilayers			Type	A1 Journal article
	Year	2019	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	99	Issue	2	Pages	024425
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Interface effect in complex oxide thin-film heterostructures lies at the vanguard of current research to design technologically relevant functionality and explore emergent physical phenomena. While most of the previous works focus on the perovskite/perovskite heterostructures, the study of perovskite/brownmillerite interfaces remains in its infancy. Here, we investigate spontaneously stabilized perovskite-ferromagnet (SrCoO3-delta)/brownmillerite-antiferromagnet (SrCoO2.5) bilayer with T-N > T-C and discover an unconventional interfacial magnetic exchange bias effect. From magnetometry investigations, it is rationalized that the observed effect stems from the interfacial ferromagnet/antiferromagnet coupling. The possibility for coupled ferromagnet/spin-glass interface engendering such effect is ruled out. Strikingly, a finite coercive field persists in the paramagnetic state of SrCoO3-delta,whereas the exchange bias field vanishes at T-C . We conjecture the observed effect to be due to the effective external quenched staggered field provided by the antiferromagnetic layer for the ferromagnetic spins at the interface. Our results not only unveil a paradigm to tailor the interfacial magnetic properties in oxide heterostructures without altering the cations at the interface, but also provide a purview to delve into the fundamental aspects of exchange bias in such unusual systems, paving a big step forward in thin-film magnetism.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000456481900003	Publication Date	2019-01-23
	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	2	Open Access	OpenAccess
	Notes	; We are grateful to Sachin Sarangi for his superb technical support during magnetic measurements. We thank Gopal Pradhan for fruitful discussion. We thank Zhicheng Zhong for reading the manuscript and for suggestions. We thank T. Som for extending laboratory facility. D.S. and B.C.B. acknowledge the financial support from Max-Planck Society through Max Planck Partner Group. S.G.B. acknowledges the INSPIRE Faculty Fellowship Programme (DSTO1899) for the financial support. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ admin @ c:irua:157562			Serial	5248
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	Author	Neek-Amal, M.; Rashidi, R.; Nair, R.R.; Neilson, D.; Peeters, F.M.
	Title	Electric-field-induced emergent electrical connectivity in graphene oxide			Type	A1 Journal article
	Year	2019	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	99	Issue	11	Pages	115425
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Understanding the appearance of local electrical connectivity in liquid filled layered graphene oxide subjected to an external electric field is important to design electrically controlled smart permeable devices and also to gain insight into the physics behind electrical effects on confined water permeation. Motivated by recent experiments [K. G. Zhou et al. Nature (London) 559, 236 (2018)], we introduce a new model with random percolating paths for electrical connectivity in micron thick water filled layered graphene oxide, which mimics parallel resistors connected across the top and bottom electrodes. We find that a strong nonuniform radial electric field of the order similar to 10-50 mV/nm can be induced between layers depending on the current flow through the formed conducting paths. The maxima of the induced fields are not necessarily close to the electrodes and may be localized in the middle region of the layered material. The emergence of electrical connectivity and the associated electrical effects have a strong influence on the surrounding fluid in terms of ionization and wetting which subsequently determines the permeation properties.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000461960100001	Publication Date	2019-03-19
	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. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ admin @ c:irua:158534			Serial	5206
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	Author	Aslani, Z.; Sisakht, E.T.; Fazileh, F.; Ghorbanfekr-Kalashami, H.; Peeters, F.M.
	Title	Conductance fluctuations of monolayer GeSnH₂$ in the topological phase using a low-energy effective tight-binding Hamiltonian			Type	A1 Journal article
	Year	2019	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	99	Issue	11	Pages	115421
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	An effective tight-binding (TB) Hamiltonian for monolayer GeSnH2 is constructed which has an inversion-asymmetric honeycomb structure. The low-energy band structure of our TB model agrees very well with previous ab initio calculations even under biaxial tensile strain. Our model predicts a phase transition at 7.5% biaxial tensile strain in agreement with DFT calculations. Upon 8.5% strain the system exhibits a band gap of 134 meV, suitable for room temperature applications. It is shown that an external applied magnetic field produces a special phase which is a combination of the quantum Hall (QH) and quantum spin Hall (QSH) phases; and at a critical magnetic field strength the QSH phase completely disappears. The topological nature of the phase transition is confirmed from: (1) the calculation of the Z(2) topological invariant, and (2) quantum transport properties of disordered GeSnH2 nanoribbons which allows us to determine the universality class of the conductance fluctuations. The application of an external applied magnetic field reduces the conductance fluctuations by a factor of root 2.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000461958900006	Publication Date	2019-03-15
	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	; This work was supported by the FLAG-ERA project TRANS-2D-TMD. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ admin @ c:irua:158538			Serial	5199
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	Author	Menezes, R.M.; Mulkers, J.; de Souza Silva, C.C.; Milošević, M.V.
	Title	Deflection of ferromagnetic and antiferromagnetic skyrmions at heterochiral interfaces			Type	A1 Journal article
	Year	2019	Publication	Physical review B	Abbreviated Journal	Phys Rev B
	Volume	99	Issue	10	Pages	104409
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Devising magnetic nanostructures with spatially heterogeneous Dzyaloshinskii-Moriya interaction (DMI) is a promising pathway toward advanced confinement and control of magnetic skyrmions in potential devices. Here we discuss theoretically how a skyrmion interacts with a heterochiral interface using micromagnetic simulations and analytic arguments. We show that a heterochiral interface deflects the trajectory of ferromagnetic (FM) skyrmions, and that the extent of such deflection is tuned by the applied spin-polarized current and the difference in DMI across the interface. Further, we show that this deflection is characteristic of the FM skyrmion, and it is completely absent in the antiferromagnetic (AFM) case. In turn, we reveal that the AFM skyrmion achieves much higher velocities than its FM counterpart, yet experiences far stronger confinement in nanoengineered heterochiral tracks, which reinforces AFM skyrmions as a favorable choice for skyrmion-based devices.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000460720600005	Publication Date	2019-03-07
	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 supported by the Research Foundation-Flanders (FWO-Vlaanderen) and Brazilian Agencies FACEPE under Grant No. APQ-0198-1.05/14, CAPES and CNPq. ;			Approved	Most recent IF: 3.836
	Call Number	UA @ admin @ c:irua:158557			Serial	5203
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