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Author Lebedev, O.I.; Verbeeck, J.; Van Tendeloo, G.; Dubourdieu, C.; Rosina, M.; Chaudouët, P.
  Title Structure and properties of artificial [(La0.7Sr0.3MnO3)m(SrTiO3)n]15 superlattices on (001)SrTiO3 Type A1 Journal article
  Year 2003 Publication Journal of applied physics Abbreviated Journal J Appl Phys
  Volume (up) 94 Issue 12 Pages 7646-7656
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Complex [(La0.7Sr0.3MnO3)(m)(SrTiO3)(n)] [(LSMO)(m)/(STO)(8)](15) superlattices with different layer thicknesses (m=5, 8, 12, 16, 32) have been prepared using pulsed liquid injection metalorganic chemical vapor deposition. Transmission electron microscopy and electron diffraction reveal a very clear and well-separated layer sequence. The remarkable microstructure, as well as the ferromagnetic transition temperature, depends on the LSMO layer thickness. Apart from a very clear layer sequence, electron microscopy shows evidence of a self-assembled nanostructure formation: SrMnO3 nanoinclusions and associated SrTiO3-SrMnO3 thin walls. A formation model and growth mechanism for the self-assembled structure is proposed, based on high resolution and energy filtered elemental imaging. (C) 2003 American Institute of Physics.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000186969900042 Publication Date 2003-12-04
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0021-8979; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.068 Times cited 22 Open Access
  Notes Approved Most recent IF: 2.068; 2003 IF: 2.171
  Call Number UA @ lucian @ c:irua:54822 Serial 3292
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Author Milošević, M.V.; Peeters, F.M.
  Title Vortex-antivortex nucleation in magnetically nanotextured superconductors: magnetic-field-driven and thermal scenarios Type A1 Journal article
  Year 2005 Publication Physical review letters Abbreviated Journal Phys Rev Lett
  Volume (up) 94 Issue Pages 227001,1-4
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication New York, N.Y. Editor
  Language Wos 000229700800059 Publication Date 2005-06-06
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0031-9007;1079-7114; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 8.462 Times cited 48 Open Access
  Notes Approved Most recent IF: 8.462; 2005 IF: 7.489
  Call Number UA @ lucian @ c:irua:57243 Serial 3859
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Author da Costa; Zarenia, M.; Chaves, A.; Pereira, J.M., Jr.; Farias, G.A.; Peeters, F.M.
  Title Hexagonal-shaped monolayer-bilayer quantum disks in graphene : a tight-binding approach Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 94 Pages 035415
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Using the tight-binding approach, we investigate confined states in two different hybrid monolayer-bilayer systems: (i) a hexagonal monolayer area surrounded by bilayer graphene in the presence of a perpendicularly applied electric field and (ii) a hexagonal bilayer graphene dot surrounded by monolayer graphene. The dependence of the energy levels on dot size and external magnetic field is calculated. We find that the energy spectrum for quantum dots with zigzag edges consists of states inside the gap which range from dot-localized states, edge states, to mixed states coexisting together, whereas for dots with armchair edges, only dot-localized states are observed.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000379502200008 Publication Date 2016-07-11
  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 11 Open Access
  Notes ; This work was financially supported by CNPq, under contract NanoBioEstruturas No. 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, the Brazilian Program Science Without Borders (CsF), and the Lemann Foundation. ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:134947 Serial 4190
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Author Zhao, H.J.; Wu, W.; Zhou, W.; Shi, Z.X.; Misko, V.R.; Peeters, F.M.
  Title Reentrant dynamics of driven pancake vortices in layered superconductors Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 94 Pages 024514
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The dynamics of driven pancake vortices in layered superconductors is studied using molecular-dynamics simulations. We found that, with increasing driving force, for strong interlayer coupling, the preexisted vortex lines either directly depin or first transform to two-dimensional (2D) pinned states before they are depinned, depending on the pinning strength. In a narrow region of pinning strengths, we found an interesting repinning process, which results in a negative differential resistance. For weak interlayer coupling, individually pinned pancake vortices first form disordered 2D flow and then transform to ordered three-dimensional (3D) flow with increasing driving force. However, for extremely strong pinning, the random pinning-induced thermal-like Langevin forces melt 3D vortex lines, which results in a persistent 2D flow in the fast-sliding regime. In the intermediate regime, the peak effect is found: With increasing driving force, the moving pancake vortices first crystallize to moving 3D vortex lines, and then these 3D vortex lines are melted, leading to the appearance of a reentrant 2D flow state. Our results are summarized in a dynamical phase diagram.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000380097800006 Publication Date 2016-07-18
  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 3 Open Access
  Notes ; We acknowledge useful discussions with C. Olson Reichhardt. This work was supported by the Natural Science Foundation of Jiangsu Province (Grant No. BK20150595), National Natural Science Foundation of China (Grants No. NSFC-U1432135 and No. 11611140101). V.R.M. acknowledges support from the “Odysseus” program of the Flemish Government and Flemish Science Foundation (FWO-Vl), the FWO-Vl, and the Research Fund of the University of Antwerp. ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:134943 Serial 4238
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Author Zhang, L.; Fernández Becerra, V.; Covaci, L.; Milošević, M.V.
  Title Electronic properties of emergent topological defects in chiral p-wave superconductivity Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 94 Pages 024520
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Chiral p-wave superconductors in applied magnetic field can exhibit more complex topological defects than just conventional superconducting vortices, due to the two-component order parameter (OP) and the broken time-reversal symmetry. We investigate the electronic properties of those exotic states, some of which contain clusters of one-component vortices in chiral components of the OP and/or exhibit skyrmionic character in the relative OP space, all obtained as a self-consistent solution of the microscopic Bogoliubov-de Gennes equations. We reveal the link between the local density of states (LDOS) of the novel topological states and the behavior of the chiral domain wall between the OP components, enabling direct identification of those states in scanning tunneling microscopy. For example, a skyrmion always contains a closed chiral domain wall, which is found to be mapped exactly by zero-bias peaks in LDOS. Moreover, the LDOS exhibits electron-hole asymmetry, which is different from the LDOS of conventional vortex states with same vorticity. Finally, we present the magnetic field and temperature dependence of the properties of a skyrmion, indicating that this topological defect can be surprisingly large in size, and can be pinned by an artificially indented nonsuperconducting closed path in the sample. These features are expected to facilitate the experimental observation of skyrmionic states, thereby enabling experimental verification of chirality in emerging superconducting materials.
  Address
  Corporate Author Thesis
  Publisher American Physical Society Place of Publication New York, N.Y Editor
  Language Wos 000381479500002 Publication Date 2016-07-26
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2469-9969 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 27 Open Access
  Notes ; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO). ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:135742 Serial 4303
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Author Klimin, S.N.; Tempere, J.; Verhelst, N.; Milošević, M.V.
  Title Finite-temperature vortices in a rotating Fermi gas Type A1 Journal article
  Year 2016 Publication Physical review A Abbreviated Journal Phys Rev A
  Volume (up) 94 Issue 94 Pages 023620
  Keywords A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT)
  Abstract Vortices and vortex arrays have been used as a hallmark of superfluidity in rotated, ultracold Fermi gases. These superfluids can be described in terms of an effective field theory for a macroscopic wave function representing the field of condensed pairs, analogous to the Ginzburg-Landau theory for superconductors. Here we establish how rotation modifies this effective field theory, by rederiving it starting from the action of Fermi gas in the rotating frame of reference. The rotation leads to the appearance of an effective vector potential, and the coupling strength of this vector potential to the macroscopic wave function depends on the interaction strength between the fermions, due to a renormalization of the pair effective mass in the effective field theory. The mass renormalization derived here is in agreement with results of functional renormalization-group theory. In the extreme Bose-Einstein condensate regime, the pair effective mass tends to twice the fermion mass, in agreement with the physical picture of a weakly interacting Bose gas of molecular pairs. Then we use our macroscopic-wave-function description to study vortices and the critical rotation frequencies to form them. Equilibrium vortex state diagrams are derived and they are in good agreement with available results of the Bogoliubov-de Gennes theory and with experimental data.
  Address
  Corporate Author Thesis
  Publisher American Physical Society Place of Publication New York, N.Y. Editor
  Language Wos 000381473100001 Publication Date 2016-08-16
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2469-9934 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.925 Times cited 6 Open Access
  Notes ; We are grateful to G. C. Strinati and H. Warringa for valuable discussions. This research was supported by the Flemish Research Foundation Projects No. G.0115.12N, No. G.0119.12N, No. G.0122.12N, and No. G.0429.15N, by the Scientific Research Network of the Flemish Research Foundation, Grant No. WO.033.09N, and by the Research Fund of the University of Antwerp. ; Approved Most recent IF: 2.925
  Call Number UA @ lucian @ c:irua:135686 Serial 4304
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Author Sisakht, E.T.; Fazileh, F.; Zare, M.H.; Zarenia, M.; Peeters, F.M.
  Title Strain-induced topological phase transition in phosphorene and in phosphorene nanoribbons Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 94 Pages 085417
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Using the tight-binding (TB) approximation with inclusion of the spin-orbit interaction, we predict a topological phase transition in the electronic band structure of phosphorene in the presence of axial strains. We derive a low-energy TB Hamiltonian that includes the spin-orbit interaction for bulk phosphorene. Applying a compressive biaxial in-plane strain and perpendicular tensile strain in ranges where the structure is still stable leads to a topological phase transition. We also examine the influence of strain on zigzag phosphorene nanoribbons (zPNRs) and the formation of the corresponding protected edge states when the system is in the topological phase. For zPNRs up to a width of 100 nm the energy gap is at least three orders of magnitude larger than the thermal energy at room temperature.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000381600800004 Publication Date 2016-08-18
  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 76 Open Access
  Notes ; This work was supported by Ministry of Science, Research and Technology, Iran. M.Z. acknowledges support as a postdoctoral fellow of the Flemish Research Foundation (FWO-Vl). ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:135643 Serial 4309
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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 (up) 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 De Beule, C.; Ziani, N.T.; Zarenia, M.; Partoens, B.; Trauzettel, B.
  Title Correlation and current anomalies in helical quantum dots Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 94 Pages 155111
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We theoretically investigate the ground-state properties of a quantum dot defined on the surface of a strong three-dimensional time-reversal invariant topological insulator. Confinement is realized by ferromagnetic barriers and Coulomb interaction is treated numerically for up to seven electrons in the dot. Experimentally relevant intermediate interaction strengths are considered. The topological origin of the dot has several consequences: (i) spin polarization increases and the ground state exhibits quantum phase transitions at specific angular momenta as a function of interaction strength, (ii) the onset of Wigner correlations takes place mainly in one spin channel, and (iii) the ground state is characterized by a robust persistent current that changes sign as a function of the distance from the center of the dot.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000385242200001 Publication Date 2016-10-07
  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 3 Open Access
  Notes ; We thank F. Cavaliere, F. Crepin, C. Felser, and B. Yan for interesting discussions, and S. Curreli for performing the finite-element calculation of the magnetic field in COMSOL. C.D.B. and M.Z. are supported by the Flemish Research Foundation (FWO). N.T.Z. and B.T. acknowledge financial support by the DFG (SPP1666 and SFB1170 “ToCoTronics”), the Helmholtz Foundation (VITI), and the ENB Graduate School on “Topological Insulators.” ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:137234 Serial 4351
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Author Mirzakhani, M.; Zarenia, M.; da Costa, D.R.; Ketabi, S.A.; Peeters, F.M.
  Title Energy levels of ABC-stacked trilayer graphene quantum dots with infinite-mass boundary conditions Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 94 Pages 165423
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Using the continuum model, we investigate the confined states and the corresponding wave functions of ABC-stacked trilayer graphene (TLG) quantum dots (QDs). First, a general infinite-mass boundary condition is derived and applied to calculate the electron and hole energy levels of a circular QD in both the absence and presence of a perpendicular magnetic field. Our analytical results for the energy spectra agree with those obtained by using the tight-binding model, where a TLG QD is surrounded by a staggered potential. Our findings show that (i) the energy spectrum exhibits intervalley symmetry E-K(e)(m) = -E-K'(h)(m) for the electron (e) and hole (h) states, where m is the angular momentum quantum number, (ii) the zero-energy Landau level (LL) is formed by the magnetic states with m <= 0 for both Dirac valleys, that is different from monolayer and bilayer graphene QD with infinite-mass potential in which only one of the cones contributes, and (iii) groups of three quantum Hall edge states in the tight-binding magnetic spectrum approach the zero LL, which results from the layer symmetry in TLG QDs.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000386168000011 Publication Date 2016-10-19
  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 9 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Brazilian Council for Research (CNPq), the Science without Borders program, PRONEX/FUNCAP, and CAPES foundation. ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:138174 Serial 4353
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Author Xiao, Y.M.; Xu, W.; Van Duppen, B.; Peeters, F.M.
  Title Infrared to terahertz optical conductivity of n-type and p-type monolayer MoS2 in the presence of Rashba spin-orbit coupling Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 94 Pages 155432
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We investigate the effect of Rashba spin-orbit coupling (SOC) on the optoelectronic properties of n- and p-type monolayer MoS2. The optical conductivity is calculated within the Kubo formalism. We find that the spin-flip transitions enabled by the Rashba SOC result in a wide absorption window in the optical spectrum. Furthermore, we evaluate the effects of the polarization direction of the radiation, temperature, carrier density, and the strength of the Rashba spin-orbit parameter on the optical conductivity. We find that the position, width, and shape of the absorption peak or absorption window can be tuned by varying these parameters. This study shows that monolayer MoS2 can be a promising tunable optical and optoelectronic material that is active in the infrared to terahertz spectral range.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000386097800003 Publication Date 2016-10-18
  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 20 Open Access
  Notes ; Y.M.X. acknowledges financial support from the China Scholarship Council (CSC). This work was also supported by the National Natural Science Foundation of China (Grant No. 11574319), Ministry of Science and Technology of China (Grant No. 2011YQ130018), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. B.V.D. is supported by a Ph.D. fellowship from the Flemish Science Foundation. ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:138175 Serial 4355
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Author Yagmurcukardes, M.; Senger, R.T.; Peeters, F.M.; Sahin, H.
  Title Mechanical properties of monolayer GaS and GaSe crystals Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 94 Pages 245407
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The mechanical properties of monolayer GaS and GaSe crystals are investigated in terms of their elastic constants: in-plane stiffness (C), Poisson ratio (nu), and ultimate strength (sigma(U)) by means of first-principles calculations. The calculated elastic constants are compared with those of graphene and monolayer MoS2. Our results indicate that monolayer GaS is a stiffer material than monolayer GaSe crystals due to the more ionic character of the Ga-S bonds than the Ga-Se bonds. Although their Poisson ratio values are very close to each other, 0.26 and 0.25 for GaS and GaSe, respectively, monolayer GaS is a stronger material than monolayer GaSe due to its slightly higher sU value. However, GaS and GaSe crystals are found to be more ductile and flexible materials than graphene and MoS2. We have also analyzed the band-gap response of GaS and GaSe monolayers to biaxial tensile strain and predicted a semiconductor-metal crossover after 17% and 14% applied strain, respectively, for monolayer GaS and GaSe. In addition, we investigated how the mechanical properties are affected by charging. We found that the flexibility of single layer GaS and GaSe displays a sharp increase under 0.1e/cell charging due to the repulsive interactions between extra charges located on chalcogen atoms. These charging-controllable mechanical properties of single layers of GaS and GaSe can be of potential use for electromechanical applications.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000389503400008 Publication Date 2016-12-05
  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 108 Open Access
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. R.T.S. acknowledges the support from TUBITAK through project 114F397. ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:139229 Serial 4356
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Author Khoeini, F.; Shakouri; Peeters, F.M.
  Title Peculiar half-metallic state in zigzag nanoribbons of MoS2 : spin filtering Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 94 Pages 125412
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Layered structures of molybdenum disulfide (MoS2) belong to a new class of two-dimensional (2D) semiconductor materials in which monolayers exhibit a direct band gap in their electronic spectrum. This band gap has recently been shown to vanish due to the presence of metallic edge modes when MoS2 monolayers are terminated by zigzag edges on both sides. Here, we demonstrate that a zigzag nanoribbon of MoS2, when exposed to an external exchange field in combination with a transverse electric field, has the potential to exhibit a peculiar half-metallic nature and thereby allows electrons of only one spin direction to move. The peculiarity of such spin-selective conductors originates from a spin switch near the gap-closing region, so the allowed spin orientation can be controlled by means of an external gate voltage. It is shown that the induced half-metallic phase is resistant to random fluctuations of the exchange field as well as the presence of edge vacancies.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000383238800009 Publication Date 2016-09-09
  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 38 Open Access
  Notes ; ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:137130 Serial 4360
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Author Yagmurcukardes, M.; Torun, E.; Senger, R.T.; Peeters, F.M.; Sahin, H.
  Title Mg(OH)2-WS2 van der Waals heterobilayer : electric field tunable band-gap crossover Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 94 Pages 195403
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Magnesium hydroxide [Mg(OH)(2)] has a layered brucitelike structure in its bulk form and was recently isolated as a new member of two-dimensional monolayer materials. We investigated the electronic and optical properties of monolayer crystals of Mg(OH)(2) and WS2 and their possible heterobilayer structure by means of first-principles calculations. It was found that both monolayers of Mg(OH)(2) and WS2 are direct-gap semiconductors and these two monolayers form a typical van der Waals heterostructure with a weak interlayer interaction and a type-II band alignment with a staggered gap that spatially separates electrons and holes. We also showed that an out-of-plane electric field induces a transition from a staggered to a straddling-type heterojunction. Moreover, by solving the Bethe-Salpeter equation on top of single-shot G(0)W(0) calculations, we show that the low-energy spectrum of the heterobilayer is dominated by the intralyer excitons of the WS2 monolayer. Because of the staggered interfacial gap and the field-tunable energy-band structure, the Mg(OH)(2)-WS2 heterobilayer can become an important candidate for various optoelectronic device applications in nanoscale.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000386769400007 Publication Date 2016-11-03
  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 38 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. is supported by a FWOPegasus Long Marie Curie Fellowship. H.S. and R.T.S. acknowledge support from TUBITAK through Project No. 114F397. H.S. acknowledges support from Bilim Akademisi – The Science Academy, Turkey, under the BAGEP program. ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:138205 Serial 4364
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Author Fernández Becerra, V.; Milošević, M.V.
  Title Multichiral ground states in mesoscopic p-wave superconductors Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 94 Pages 184517
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Using Ginzburg-Landau formalism, we investigate the effect of confinement on the ground state of mesoscopic chiral p-wave superconductors in the absence of magnetic field. We reveal stable multichiral states with domain walls separating the regions with different chiralities, as well as monochiral states with spontaneous currents flowing along the edges. We show that multichiral states can exhibit identifying signatures in the spatial profile of the magnetic field if those are not screened by edge currents in the case of strong confinement. Such magnetic detection of domain walls in topological superconductors can serve as long-sought evidence of broken time-reversal symmetry. Furthermore, when applying electric current to mesoscopic p-wave samples, we found a hysteretic behavior in the current-voltage characteristic that distinguishes states with and without domain walls, thereby providing another useful hallmark for indirect confirmation of chiral p-wave superconductivity.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000388816700001 Publication Date 2016-11-30
  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 7 Open Access
  Notes ; This work was supported by the Research Foundation-Flanders (FWO-Vlaanderen), the COST-EU action MP1201, and the MultiSuper network. ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:139241 Serial 4456
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Author Petrovic, M.D.; Peeters, F.M.
  Title Quantum transport in graphene Hall bars: Effects of vacancy disorder Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 94 Pages 235413
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Using the tight-binding model, we investigate the influence of vacancy disorder on electrical transport in graphene Hall bars in the presence of quantizing magnetic fields. Disorder, induced by a random distribution of monovacancies, breaks the graphene sublattice symmetry and creates states localized on the vacancies. These states are observable in the bend resistance, as well as in the total DOS. Their energy is proportional to the square root of the magnetic field, while their localization length is proportional to the cyclotron radius. At the energies of these localized states, the electron current flows around the monovacancies and, as we show, it can follow unexpected paths depending on the particular arrangement of vacancies. We study how these localized states change with the vacancy concentration, and what are the effects of including the next-nearest-neighbor hopping term. Our results are also compared with the situation when double vacancies are present in the system. Double vacancies also induce localized states, but their energy and magnetic field dependencies are different. Their localization energy scales linearly with the magnetic field, and their localization length appears not to depend on the field strength.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000389574200005 Publication Date 2016-12-14
  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 supported by the Methusalem program of the Flemish government. ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:140237 Serial 4459
Permanent link to this record
 

 
Author Heshmati-Moulai, A.; Simchi, H.; Esmaeilzadeh, M.; Peeters, F.M.
  Title Phase transition and spin-resolved transport in MoS2 nanoribbons Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 94 Pages 235424
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The electronic structure and transport properties of monolayer MoS2 are studied using a tight-binding approach coupled with the nonequilibrium Green's function method. A zigzag nanoribbon of MoS2 is conducting due to the intersection of the edge states with the Fermi level that is located within the bulk gap. We show that applying a transverse electric field results in the disappearance of this intersection and turns the material into a semiconductor. By increasing the electric field the band gap undergoes a two stage linear increase after which it decreases and ultimately closes. It is shown that in the presence of a uniform exchange field, this electric field tuning of the gap can be exploited to open low energy domains where only one of the spin states contributes to the electronic conductance. This introduces possibilities in designing spin filters for spintronic applications.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000394546100005 Publication Date 2016-12-20
  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 7 Open Access
  Notes ; ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:141978 Serial 4557
Permanent link to this record
 

 
Author Cavalcante, L.S.; Chaves, A.; da Costa, D.R.; Farias, G.A.; Peeters, F.M.
  Title All-strain based valley filter in graphene nanoribbons using snake states Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 7 Pages 075432
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract A pseudomagnetic field kink can be realized along a graphene nanoribbon using strain engineering. Electron transport along this kink is governed by snake states that are characterized by a single propagation direction. Those pseudomagnetic fields point towards opposite directions in the K and K' valleys, leading to valley polarized snake states. In a graphene nanoribbon with armchair edges this effect results in a valley filter that is based only on strain engineering. We discuss how to maximize this valley filtering by adjusting the parameters that define the stress distribution along the graphene ribbon.
  Address
  Corporate Author Thesis
  Publisher American Physical Society Place of Publication New York, N.Y Editor
  Language Wos 000381889300002 Publication Date 2016-08-23
  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 29 Open Access
  Notes ; Discussions with R. Grassi are gratefully acknowledged. This work was supported by the Brazilian Council for Research (CNPq), under the PRONEX/FUNCAP and Science Without Borders (SWB) programs, CAPES, the Lemann Foundation, and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:144667 Serial 4639
Permanent link to this record
 

 
Author Fernandez, M.S.; Peeters, F.M.; Neek-Amal, M.
  Title Electric-field-induced structural changes in water confined between two graphene layers Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 4 Pages 045436
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract An external electric field changes the physical properties of polar liquids due to the reorientation of their permanent dipoles. Using molecular dynamics simulations, we predict that an in-plane electric field applied parallel to the channel polarizes water molecules which are confined between two graphene layers, resulting in distinct ferroelectricity and electrical hysteresis. We found that electric fields alter the in-plane order of the hydrogen bonds: Reversing the electric field does not restore the system to the nonpolar initial state, instead a residual dipole moment remains in the system. The square-rhombic structure of 2D ice is transformed into two rhombic-rhombic structures. Our study provides insights into the ferroelectric state of water when confined in nanochannels and shows how this can be tuned by an electric field.
  Address
  Corporate Author Thesis
  Publisher American Physical Society Place of Publication New York, N.Y Editor
  Language Wos 000381485200005 Publication Date 2016-07-27
  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 31 Open Access
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:144684 Serial 4649
Permanent link to this record
 

 
Author Aierken, Y.; Leenaerts, O.; Peeters, F.M.
  Title Intrinsic magnetism in penta-hexa-graphene: A first-principles study Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B
  Volume (up) 94 Issue 15 Pages 155410
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Recently, several monolayer carbon allotropes have been proposed. The magnetic properties of these metal-free materials are investigated, and we explore a special type of all carbon system having an intrinsic magnetic ground state. The structure is composed of mixing pentagonal and hexagonal rings of carbon atoms, such that the unit cell consists of eleven atoms, where two C atoms each have an unpaired electron each with a local magnetic moment. The antiferromagnetic (AFM) state has a lower energy than the ferromagnetic (FM) one. However, a strain-driven transition to the FM ground state is possible. The application of strain not only lowers the energy of the FM state but it also induces an energy barrier of about 13 meV/(magnetic atom) to protect the FM state from excitation. Our findings based on first-principles calculations will motivate other works on similar metal-free magnetic monolayer materials and will have an impact on their possible applications in spintronic devices.
  Address
  Corporate Author Thesis
  Publisher American Physical Society Place of Publication New York, N.Y Editor
  Language Wos 000385623700006 Publication Date 2016-10-10
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 3.836 Times cited 13 Open Access
  Notes ; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation-Flanders (FWO) and the Flemish Government-department EWI. ; Approved Most recent IF: 3.836
  Call Number UA @ lucian @ c:irua:144641 Serial 4665
Permanent link to this record
 

 
Author Orlova, N.V.; Kuopanportti, P.; Milošević, M.V.
  Title Skyrmionic vortex lattices in coherently coupled three-component Bose-Einstein condensates Type A1 Journal article
  Year 2016 Publication Physical Review A Abbreviated Journal Phys Rev A
  Volume (up) 94 Issue 2 Pages 023617
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We show numerically that a harmonically trapped and coherently Rabi-coupled three-component Bose-Einstein condensate can host unconventional vortex lattices in its rotating ground state. The discovered lattices incorporate square and zig-zag patterns, vortex dimers and chains, and doubly quantized vortices, and they can be quantitatively classified in terms of a skyrmionic topological index, which takes into account the multicomponent nature of the system. The exotic ground-state lattices arise due to the intricate interplay of the repulsive density-density interactions and the Rabi couplings as well as the ubiquitous phase frustration between the components. In the frustrated state, domain walls in the relative phases can persist between some components even at strong Rabi coupling, while vanishing between others. Consequently, in this limit the three-component condensate effectively approaches a two-component condensate with only density-density interactions. At intermediate Rabi coupling strengths, however, we face unique vortex physics that occurs neither in the two-component counterpart nor in the purely density-density-coupled three-component system.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000381303800006 Publication Date 2016-08-12
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2469-9926;2469-9934; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 2.925 Times cited 16 Open Access
  Notes ; This work was supported by the Research Foundation Flanders (FWO). P. K. acknowledges financial support from the Emil Aaltonen Foundation, the Finnish Cultural Foundation, the Magnus Ehrnrooth Foundation, and the Technology Industries of Finland Centennial Foundation. The authors thank R. P. Anderson, E. Babaev, I. O. Cherednikov, V. R. Misko, T. P. Simula, and J. Tempere for useful comments and discussions. ; Approved Most recent IF: 2.925
  Call Number UA @ lucian @ c:irua:144673 Serial 4688
Permanent link to this record
 

 
Author Van Schoubroeck, S.; Van Dael, M.; Van Passel, S.; Malina, R.
  Title A review of sustainability indicators for biobased chemicals Type A1 Journal article
  Year 2018 Publication Renewable & Sustainable Energy Reviews Abbreviated Journal Renew Sust Energ Rev
  Volume (up) 94 Issue 94 Pages 115-126
  Keywords A1 Journal article; Economics; Engineering sciences. Technology; Engineering Management (ENM)
  Abstract Companies dealing with chemical products have to cope with large amounts of waste and environmental risk due to the use and production of toxic substances. Against this background, increasing attention is being paid to green chemistry and the translation of this concept into biobased chemicals. Given the multitude of economic, environmental and societal impacts that the production and use of biobased chemicals have on sustainability, assessment approaches need to be developed that allow for measurement and comparison of these impacts. To evaluate sustainability in the context of policy and decision-making, indicators are generally accepted means. However, sustainability indicators currently predominantly exist for low-value applications in the bioeconomy, like bioenergy and biofuels. In this paper, a review of the state-of-the-art sustainability indicators for biobased chemicals is conducted and a gap analysis is performed to identify indicator development needs. Based on the analysis, a clear hierarchy within the concept of sustainability is found where the environmental aspect dominates over economic and social indicators. All one-dimensional indicator-sets account for environmental impacts (50%), whereas two-dimensional sets complement the environmental issues with economic indicators (34%). Moreover, even the sets encompassing all three sustainability dimensions (16%) do not account for the dynamics and interlinkages between the environment, economy and society. Using results from the literature review, an indicator list is presented that captures all indicators currently used within sustainability assessment of biobased chemicals. Finally, a framework is proposed for future indicator selection using a stakeholder survey to obtain a prioritized list of sustainability indicators for biobased chemicals.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000446310000008 Publication Date 2018-06-07
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1364-0321; 1879-0690 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 8.05 Times cited 17 Open Access
  Notes ; ; Approved Most recent IF: 8.05
  Call Number UA @ admin @ c:irua:154140 Serial 6244
Permanent link to this record
 

 
Author Neven, L.; Barich, H.; Ching, H.Y.V.; Khan, S.U.; Colomier, C.; Patel, H.H.; Gorun, S.M.; Verbruggen, S.; Van Doorslaer, S.; De Wael, K.
  Title Correlation between the fluorination degree of perfluorinated zinc phthalocyanines, their singlet oxygen generation ability, and their photoelectrochemical response for phenol sensing Type A1 Journal article
  Year 2022 Publication Analytical chemistry Abbreviated Journal Anal Chem
  Volume (up) 94 Issue 13 Pages 5221-5230
  Keywords A1 Journal article; Organic synthesis (ORSY); Sustainable Energy, Air and Water Technology (DuEL); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
  Abstract Electron-withdrawing perfluoroalkyl peripheral groups grafted on phthalocyanine (Pc) macrocycles improve their single-site isolation, solubility, and resistance to self-oxidation, all beneficial features for catalytic applications. A high degree of fluorination also enhances the reducibility of Pcs and could alter their singlet oxygen (1O2) photoproduction. The ethanol/toluene 20:80 vol % solvent mixture was found to dissolve perfluorinated FnPcZn complexes, n = 16, 52, and 64, and minimize the aggregation of the sterically unencumbered F16PcZn. The 1O2 production ability of FnPcZn complexes was examined using 9,10-dimethylanthracene (DMA) and 2,2,6,6-tetramethylpiperidine (TEMP) in combination with UV–vis and electron paramagnetic resonance (EPR) spectroscopy, respectively. While the photoreduction of F52PcZn and F64PcZn in the presence of redox-active TEMP lowered 1O2 production, DMA was a suitable 1O2 trap for ranking the complexes. The solution reactivity was complemented by solid-state studies via the construction of photoelectrochemical sensors based on TiO2-supported FnPcZn, FnPcZn|TiO2. Phenol photo-oxidation by 1O2, followed by its electrochemical reduction, defines a redox cycle, the 1O2 production having been found to depend on the value of n and structural features of the supported complexes. Consistent with solution studies, F52PcZn was found to be the most efficient 1O2 generator. The insights on reactivity testing and structural–activity relationships obtained may be useful for designing efficient and robust sensors and for other 1O2-related applications of FnPcZn.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000786254500002 Publication Date 2022-03-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 7.4 Times cited Open Access OpenAccess
  Notes Approved Most recent IF: 7.4
  Call Number UA @ admin @ c:irua:187522 Serial 7141
Permanent link to this record
 

 
Author Khan, S.U.; Trashin, S.; Beltran, V.; Korostei, Y.S.; Pelmus, M.; Gorun, S.M.; Dubinina, T., V.; Verbruggen, S.W.; De Wael, K.
  Title Photoelectrochemical behavior of phthalocyanine-sensitized TiO₂ in the presence of electron-shuttling mediators Type A1 Journal article
  Year 2022 Publication Analytical chemistry Abbreviated Journal Anal Chem
  Volume (up) 94 Issue 37 Pages 12723-12731
  Keywords A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
  Abstract Dye-sensitized TiO(2 )has found many applications for dye sensitized solar cells (DSSC), solar-to-chemical energy conversion, water/air purification systems, and (electro)chemical sensors. We report an electrochemical system for testing dye-sensitized materials that can be utilized in photoelectrochemical (PEC) sensors and energy conversion. Unlike related systems, the reported system does not require a direct electron transfer from semiconductors to electrodes. Rather, it relies on electron shuttling by redox mediators. A range of model photocatalytic materials were prepared using three different TiO2 materials (P25, P90, and PC500) and three sterically hindered phthalocyanines (Pcs) with electron-rich tert-butyl substituents (t-Bu4PcZn, t-Bu4PcAlCl, and t-Bu4PcH2). The materials were compared with previously developed TiO(2 )modified by electron-deficient, also sterically hindered fluorinated phthalocyanine F64PcZn, a singlet oxygen (O-1(2)) producer, as well as its metal-free derivative, F64PcH2. The PEC activity depended on the redox mediator, as well as the type of TiO2 and Pc. By comparing the responses of one-electron shuttles, such as K4Fe(CN)(4), and O-1(2)-reactive electron shuttles, such as phenol, it is possible to reveal the action mechanism of the supported photosensitizers, while the overall activity can be assessed using hydroquinone. t-Bu4PcAlCl showed significantly lower blank responses and higher specific responses toward chlorophenols compared to t-Bu4PcZn due to the electron-withdrawing effect of the Al3+ metal center. The combination of reactivity insights and the need for only microgram amounts of sensing materials renders the reported system advantageous for practical applications.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000855284300001 Publication Date 2022-09-12
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 7.4 Times cited Open Access OpenAccess
  Notes Approved Most recent IF: 7.4
  Call Number UA @ admin @ c:irua:190602 Serial 7190
Permanent link to this record
 

 
Author Reichhardt, C.; Reichhardt, C.J.O.; Milošević, M.V.
  Title Statics and dynamics of skyrmions interacting with disorder and nanostructures Type A1 Journal article
  Year 2022 Publication Reviews of modern physics Abbreviated Journal Rev Mod Phys
  Volume (up) 94 Issue 3 Pages 035005-35061
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Magnetic skyrmions are topologically stable nanoscale particlelike objects that were discovered in 2009. Since that time, intense research interest in the field has led to the identification of numerous compounds that support skyrmions over a range of conditions spanning from cryogenic to room temperatures. Skyrmions can be set into motion under various types of driving, and the combination of their size, stability, and dynamics makes them ideal candidates for numerous applications. At the same time, skyrmions represent a new class of system in which the energy scales of the skyrmion-skyrmion interactions, sample disorder, temperature, and drive can compete. A growing body of work indicates that the static and dynamic states of skyrmions can be influenced strongly by pinning or disorder in the sample; thus, an understanding of such effects is essential for the eventual use of skyrmions in applications. The current state of knowledge regarding individual skyrmions and skyrmion assemblies interacting with quenched disorder or pinning is reviewed. The microscopic mechanisms for skyrmion pinning, including the repulsive and attractive interactions that can arise from impurities, grain boundaries, or nanostructures, are outlined. This is followed by descriptions of depinning phenomena, sliding states over disorder, the effect of pinning on the skyrmion Hall angle, the competition between thermal and pinning effects, the control of skyrmion motion using ordered potential landscapes such as one-or two-dimensional periodic asymmetric substrates, the creation of skyrmion diodes, and skyrmion ratchet effects. Highlighted are the distinctions arising from internal modes and the strong gyrotropic or Magnus forces that cause the dynamical states of skyrmions to differ from those of other systems with pinning, such as vortices in type-II superconductors, charge density waves, or colloidal particles. Throughout this review future directions and open questions related to the and in are also discussed.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000861559900001 Publication Date 2022-09-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0034-6861; 1539-0756 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 44.1 Times cited 12 Open Access OpenAccess
  Notes Approved Most recent IF: 44.1
  Call Number UA @ admin @ c:irua:191507 Serial 7339
Permanent link to this record
 

 
Author Hellar-Kihampa, H.; Potgieter-Vermaak, S.; van Meel, K.; Gatto Rotondo, G.; Kishimba, M.; Van Grieken, R.
  Title Elemental composition of bottom-sediments from Pangani river basin, Tanzania : lithogenic and anthropogenic sources Type A1 Journal article
  Year 2012 Publication Toxicological and environmental chemistry Abbreviated Journal
  Volume (up) 94 Issue 3 Pages 525-544
  Keywords A1 Journal article; Pharmacology. Therapy; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract River-bed sediments from the Pangani basin, Tanzania, were characterized for elemental compositions, following contamination risks from rapid expansions of human activities in the area. Samples were collected during two individual seasons and analyzed by high-polarizing beam energy dispersive X-ray fluorescence (EDXRF) for eight major and 14 trace elements. Evaluation of enrichment factors (EFs) was used to investigate the elemental flux and assess the contributions of natural and anthropogenic influences. The abundances of the major elements followed the order Si > Al > Fe > Ca > K > Ti > Mn > P, similar to that of the upper earth's crust, and were generally from the weathering of the bed-rock. The high concentrations of typical anthropogenic trace-elements (Cr < 160 mg kg−1, V < 85 mg kg−1, Ni < 60 mg kg−1, Cu < 87 mg kg−1, La < 90 mg kg−1) coupled with high EFs (>2) in some locations indicated contamination associated with agricultural and industrial activities. Factor analysis extracted five principal components that contributed to 96.0% of the total observed variance. The results indicated that river-bed sediments of the Pangani basin were influenced to a larger extent by lithogenic sources than anthropogenic impacts.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000304276100007 Publication Date 2012-01-16
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0277-2248 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:97080 Serial 7889
Permanent link to this record
 

 
Author Saiz-Jimenez, C.; Garcia-Rowe, J.; Garcia Del Cura, M.A.; Ortega-Camvo, J.J.; Roekens, E.; Van Grieken, R.
  Title Endolithic cyanobacteria in Maastricht limestone Type A1 Journal article
  Year 1990 Publication The science of the total environment Abbreviated Journal
  Volume (up) 94 Issue 3 Pages 209-220
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
  Abstract The Maastricht limestone used for the construction of the 14th century O.L. Basilica in Tongeren, Belgium, is a light yellowish, porous, soft rock of the Late Cretaceous age. The limestone has a high carbonate content (> 95%); quartz and glauconite occur rarely. On the north side of the building, there is extensive growth of epilithic algae. On the south side, an assemblage of organisms was observed beneath the abiotic surface. This community, developed as a green layer 1 mm below the surface, is dominated by cyanobacteria. A moss was also present. The organisms were studied by transmitted light, phase contrast and scanning electron microscopy, and isolated in cultures. The cyanobacteria belong to the genera Synechococcus and Chroococcidiopsis, and the moss was identified as Tortula muralis Hedw. The organic matter present in the green layer was characterized in terms of molecular components using analytical pyrolysis. Pyrolysis products from polysaccharides and proteins, and evaporation/pyrolysis products from lipids, comprise the vast majority of identified compounds. The identification of specific biomarkers such as 7-methylheptadecane is further evidence of the presence of cyanobacteria. Phytenes and phytadienes are indicative of phototrophic organisms, as they are pyrolysis products from chlorophylls.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos A1990DF51800004 Publication Date 2003-09-12
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0048-9697; 1879-1026 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:116654 Serial 7902
Permanent link to this record
 

 
Author Ma, X.; Pavlidis, G.; Dillon, E.; Beltran, V.; Schwartz, J.J.; Thoury, M.; Borondics, F.; Sandt, C.; Kjoller, K.; Berrie, B.H.; Centrone, A.
  Title Micro to nano : multiscale IR analyses reveal zinc soap heterogeneity in a 19th-century painting by Corot Type A1 Journal article
  Year 2022 Publication Analytical chemistry Abbreviated Journal
  Volume (up) 94 Issue 7 Pages 3103-3110
  Keywords A1 Journal article; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
  Abstract Formation and aggregation of metal carboxylates (metal soaps) can degrade the appearance and integrity of oil paints, challenging efforts to conserve painted works of art. Endeavors to understand the root cause of metal soap formation have been hampered by the limited spatial resolution of Fourier transform infrared microscopy (mu-FTIR). We overcome this limitation using optical photothermal infrared spectroscopy (O-PTIR) and photothermal-induced resonance (PTIR), two novel methods that provide IR spectra with approximate to 500 and approximate to 10 nm spatial resolutions, respectively. The distribution of chemical phases in thin sections from the top layer of a 19th-century painting is investigated at multiple scales (mu-FTIR approximate to 10(2) mu m(3), O-PTIR approximate to 10(-1) mu m(3), PTIR approximate to 10(-5) mu m(3)). The paint samples analyzed here are found to be mixtures of pigments (cobalt green, lead white), cured oil, and a rich array of intermixed, small (often << 0.1 mu m(3)) zinc soap domains. We identify Zn stearate and Zn oleate crystalline soaps with characteristic narrow IR peaks (approximate to 1530-1558 cm(-1)) and a heterogeneous, disordered, water-permeable, tetrahedral zinc soap phase, with a characteristic broad peak centered at approximate to 1596 cm(-1). We show that the high signal-to-noise ratio and spatial resolution afforded by O-PTIR are ideal for identifying phase-separated (or locally concentrated) species with low average concentration, while PTIR provides an unprecedented nanoscale view of distributions and associations of species in paint. This newly accessible nanocompositional information will advance our knowledge of chemical processes in oil paint and will stimulate new art conservation practices.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000766206700011 Publication Date 2022-02-09
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0003-2700; 5206-882x ISBN Additional Links UA library record; WoS full record; WoS full record; WoS citing articles
  Impact Factor Times cited Open Access OpenAccess
  Notes Approved no
  Call Number UA @ admin @ c:irua:187380 Serial 8897
Permanent link to this record
 

 
Author Taylor, P.R.; Martin, J.M.L.; François, J.P.; Gijbels, R.
  Title An ab initio study of the C3+ cation using multireference methods Type A1 Journal article
  Year 1991 Publication The journal of chemical physics Abbreviated Journal J Chem Phys
  Volume (up) 95 Issue Pages 6530-6534
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication New York, N.Y. Editor
  Language Wos Publication Date 0000-00-00
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0021-9606 ISBN Additional Links UA library record
  Impact Factor 2.952 Times cited Open Access
  Notes Approved no
  Call Number UA @ lucian @ c:irua:720 Serial 39
Permanent link to this record
 

 
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 (up) 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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