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Author (down) Masir, M.R.; Vasilopoulos, P.; Matulis, A.; Peeters, F.M. pdf  doi
openurl 
  Title Angular confinement and direction-dependent transmission in graphene nanostructures with magnetic barriers Type A1 Journal article
  Year 2009 Publication AIP conference proceedings Abbreviated Journal  
  Volume 1199 Issue Pages 363-364  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We evaluate the transmission through magnetic barriers in graphene-based nanostructures. Several particular cases are considered: a magnetic step, single and double barriers, delta -function barriers as well as barrier structures with inhomogeneous magnetic field profiles but with average magnetic field equal to zero. The transmission exhibits a strong dependence on the direction of the incident wave vector. In general the resonant structure of the transmission is significantly more pronounced for (Dirac) electrons with linear spectrum compared to that for electrons with a parabolic one.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York Editor  
  Language Wos 000281590800171 Publication Date 2010-01-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:84892 Serial 115  
Permanent link to this record
 

 
Author (down) Masir, M.R.; Vasilopoulos, P.; Matulis, A.; Peeters, F.M. url  doi
openurl 
  Title Direction-dependent tunneling through nanostructured magnetic barriers in graphene Type A1 Journal article
  Year 2008 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 77 Issue 23 Pages 235443,1-11  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000257289500133 Publication Date 2008-06-27  
  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 212 Open Access  
  Notes Approved Most recent IF: 3.836; 2008 IF: 3.322  
  Call Number UA @ lucian @ c:irua:69639 Serial 727  
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Author (down) Masir, M.R.; Peeters, F.M. doi  openurl
  Title Scattering of Dirac electrons by a random array of magnetic flux tubes Type A1 Journal article
  Year 2013 Publication Journal of computational electronics Abbreviated Journal J Comput Electron  
  Volume 12 Issue 2 Pages 115-122  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The scattering of two-dimensional (2D) massless electrons as presented in graphene in the presence of a random array of circular magnetic flux tubes is investigated. The momentum relaxation time and the Hall factor are obtained using optical theorem techniques for scattering. Electrons with energy close to those of the Landau levels of the flux tubes exhibit resonant scattering and have a long life-time to reside inside the magnetic flux tube. These resonances appear as sharp structures in the Hall factor and the magneto-resistance.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication S.l. Editor  
  Language Wos 000320044900007 Publication Date 2013-02-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1569-8025;1572-8137; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.526 Times cited 2 Open Access  
  Notes ; This work was supported by the European Science Foundation (ESF) under the EUROCORES Program Euro-GRAPHENE within the project CONGRAN and the Flemish Science Foundation (FWO-Vl). We acknowledge fruitful discussions with A. Matulis. ; Approved Most recent IF: 1.526; 2013 IF: 1.372  
  Call Number UA @ lucian @ c:irua:109615 Serial 2950  
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Author (down) Masir, M.R.; Moldovan, D.; Peeters, F.M. pdf  doi
openurl 
  Title Pseudo magnetic field in strained graphene : revisited Type A1 Journal article
  Year 2013 Publication Solid state communications Abbreviated Journal Solid State Commun  
  Volume 175 Issue Pages 76-82  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We revisit the theory of the pseudo magnetic field as induced by strain in graphene using the tight- binding approach. A systematic expansion of the hopping parameter and the deformation of the lattice vectors is presented from which we obtain an expression for the pseudo magnetic field for low energy electrons. We generalize and discuss previous results and propose a novel effective Hamiltonian. The contributions of the different terms to the pseudo field expression are investigated for a model triaxial strain profile and are compared with the full solution. Our work suggests that the previous proposed pseudo magnetic field expression is valid up to reasonably high strain (15%) and there is no K-dependent pseudo-magnetic field.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos 000329538200010 Publication Date 2013-04-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0038-1098; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.554 Times cited 57 Open Access  
  Notes This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EURO- CORES Program EuroGRAPHENE within the project CONGRAN and the Methusalem programme of the Flemish government. Approved Most recent IF: 1.554; 2013 IF: 1.698  
  Call Number UA @ lucian @ c:irua:114805 Serial 2737  
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Author (down) Masir, M.R.; Matulis, A.; Peeters, F.M. url  doi
openurl 
  Title Quasibound states of Schrödinger and Dirac electrons in a magnetic quantum dot Type A1 Journal article
  Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 79 Issue 15 Pages 155451,1-155451,8  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The properties of a two-dimensional electron are investigated in the presence of a circular step magnetic-field profile. Both electrons with parabolic dispersion as well as Dirac electrons with linear dispersion are studied. We found that in such a magnetic quantum dot no electrons can be confined. Nevertheless close to the Landau levels quasibound states can exist with a rather long lifetime.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000265944200140 Publication Date 2009-04-30  
  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 55 Open Access  
  Notes Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:77026 Serial 2800  
Permanent link to this record
 

 
Author (down) Masir, M.R.; Matulis, A.; Peeters, F.M. url  doi
openurl 
  Title Scattering of Dirac electrons by circular mass barriers : valley filter and resonant scattering Type A1 Journal article
  Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 84 Issue 24 Pages 245413-245413,9  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The scattering of two-dimensional (2D) massless Dirac electrons is investigated in the presence of a random array of circular mass barriers. The inverse momentum relaxation time and the Hall factor are calculated and used to obtain parallel and perpendicular resistivity components within linear transport theory. We found a nonzero perpendicular resistivity component which has opposite sign for electrons in the different K and K′ valleys. This property can be used for valley filter purposes. The total cross section for scattering on penetrable barriers exhibits resonances due to the presence of quasibound states in the barriers that show up as sharp gaps in the cross section while for Schrödinger electrons they appear as peaks.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000297934500008 Publication Date 2011-12-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 32 Open Access  
  Notes ; This work was supported by the European Science Foundation (ESF) under the EUROCORES Program Euro-GRAPHENE within the project CONGRAN. ; Approved Most recent IF: 3.836; 2011 IF: 3.691  
  Call Number UA @ lucian @ c:irua:94383 Serial 2951  
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Author (down) Masir, M.R. openurl 
  Title Electronic properties of graphene in inhomogeneous magnetic fields Type Doctoral thesis
  Year 2012 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords Doctoral thesis; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Antwerpen Editor  
  Language Wos Publication Date 0000-00-00  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:98178 Serial 1001  
Permanent link to this record
 

 
Author (down) Martens, K.; Jeong, J.W.; Aetukuri, N.; Rettner, C.; Shukla, N.; Freeman, E.; Esfahani, D.N.; Peeters, F.M.; Topuria, T.; Rice, P.M.; Volodin, A.; Douhard, B.; Vandervorst, W.; Samant, M.G.; Datta, S.; Parkin, S.S.P. url  doi
openurl 
  Title Field Effect and Strongly Localized Carriers in the Metal-Insulator Transition Material VO(2) Type A1 Journal article
  Year 2015 Publication Physical review letters Abbreviated Journal Phys Rev Lett  
  Volume 115 Issue 115 Pages 196401  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The intrinsic field effect, the change in surface conductance with an applied transverse electric field, of prototypal strongly correlated VO(2) has remained elusive. Here we report its measurement enabled by epitaxial VO(2) and atomic layer deposited high-kappa dielectrics. Oxygen migration, joule heating, and the linked field-induced phase transition are precluded. The field effect can be understood in terms of field-induced carriers with densities up to approximately 5x10(13) cm(-2) which are trongly localized, as shown by their low, thermally activated mobility ( approximately 1x10(-3) cm(2)/V s at 300 K). These carriers show behavior consistent with that of Holstein polarons and strongly impact the (opto)electronics of VO(2).  
  Address IBM Research-Almaden, San Jose, California 95120, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Wos 000364024800013 Publication Date 2015-11-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0031-9007 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 8.462 Times cited 28 Open Access  
  Notes ; The authors acknowledge B. Hughes, K. Roche, L. Gao, C. Lada, J. Van Houdt, M. Heyns, J. P. Locquet, J. Delmotte, L. Krupp, L. Clark, and FWO (K. M.). S. D. and N. S. acknowledge LEAST (Low Energy Systems Technology), one of six SRC STARnet Centers, sponsored by MARCO/DARPA, for financial support. ; Approved Most recent IF: 8.462; 2015 IF: 7.512  
  Call Number c:irua:129547 Serial 4051  
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Author (down) Marmorkos, I.K.; Schweigert, V.A.; Peeters, F.M.; Lok, J.G.S. openurl 
  Title Binding of remote and spatial separated D- centers in double barrier resonant tunneling semiconductor devices Type P3 Proceeding
  Year 1996 Publication Abbreviated Journal  
  Volume Issue Pages 2769-2772  
  Keywords P3 Proceeding; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher World Scientific Place of Publication Singapore Editor  
  Language Wos Publication Date 0000-00-00  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved MATERIALS SCIENCE, MULTIDISCIPLINARY 135/271 Q2 # PHYSICS, APPLIED 70/145 Q2 # PHYSICS, CONDENSED MATTER 40/67 Q3 #  
  Call Number UA @ lucian @ c:irua:15809 Serial 241  
Permanent link to this record
 

 
Author (down) Marmorkos, I.K.; Schweigert, V.A.; Peeters, F.M. openurl 
  Title Remote and spatially separated D- centers in quasi-two-dimensional semiconductor structures Type A1 Journal article
  Year 1997 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 55 Issue Pages 5065-5072  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos A1997WL49900038 Publication Date 0000-00-00  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121; 0163-1829 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 41 Open Access  
  Notes Approved Most recent IF: 3.836; 1997 IF: NA  
  Call Number UA @ lucian @ c:irua:19289 Serial 2868  
Permanent link to this record
 

 
Author (down) Marmorkos, I.K.; Matulis, A.; Peeters, F.M. openurl 
  Title Stability of the superconducting vortex structure around a magnetic dot Type A3 Journal article
  Year 1995 Publication Physics of low-dimensional structures Abbreviated Journal  
  Volume 10/11 Issue Pages 77-86  
  Keywords A3 Journal article; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date 0000-00-00  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved PHYSICS, APPLIED 28/145 Q1 #  
  Call Number UA @ lucian @ c:irua:13036 Serial 3133  
Permanent link to this record
 

 
Author (down) Marmorkos, I.K.; Matulis, A.; Peeters, F.M. doi  openurl
  Title Vortex structure around a magnetic dot in planar superconductors Type A1 Journal article
  Year 1996 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 53 Issue Pages 2677-2685  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos A1996TV39300081 Publication Date 2002-07-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0163-1829;1095-3795; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.736 Times cited 58 Open Access  
  Notes Approved INSTRUMENTS & INSTRUMENTATION 31/56 Q3 # NUCLEAR SCIENCE & TECHNOLOGY 9/32 Q2 # PHYSICS, PARTICLES & FIELDS 24/28 Q4 # SPECTROSCOPY 28/43 Q3 #  
  Call Number UA @ lucian @ c:irua:15804 Serial 3893  
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Author (down) Marikutsa, A.; Rumyantseva, M.; Gaskov, A.; Batuk, M.; Hadermann, J.; Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D. url  doi
openurl 
  Title Effect of zinc oxide modification by indium oxide on microstructure, adsorbed surface species, and sensitivity to CO Type A1 Journal article
  Year 2019 Publication Frontiers in materials Abbreviated Journal  
  Volume 6 Issue 6 Pages  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract Additives in semiconductor metal oxides are commonly used to improve sensing behavior of gas sensors. Due to complicated effects of additives on the materials microstructure, adsorption sites and reactivity to target gases the sensing mechanism with modified metal oxides is a matter of thorough research. Herein, we establish the promoting effect of nanocrystalline zinc oxide modification by 1-7 at.% of indium on the sensitivity to CO gas due to improved nanostructure dispersion and concentration of active sites. The sensing materials were synthesized via an aqueous coprecipitation route. Materials composition, particle size and BET area were evaluated using X-ray diffraction, nitrogen adsorption isotherms, high-resolution electron microscopy techniques and EDX-mapping. Surface species of chemisorbed oxygen, OH-groups, and acid sites were characterized by probe molecule techniques and infrared spectroscopy. It was found that particle size of zinc oxide decreased and the BET area increased with the amount of indium oxide. The additive was observed as amorphous indium oxide segregated on agglomerated ZnO nanocrystals. The measured concentration of surface species was higher on In2O3-modified zinc oxide. With the increase of indium oxide content, the sensor response of ZnO/In2O3 to CO was improved. Using in situ infrared spectroscopy, it was shown that oxidation of CO molecules was enhanced on the modified zinc oxide surface. The effect of modifier was attributed to promotion of surface OH-groups and enhancement of CO oxidation on the segregated indium ions, as suggested by DFT in previous work.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000461540600001 Publication Date 2019-03-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2296-8016 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 11 Open Access OpenAccess  
  Notes ; Research was supported by the grant from Russian Science Foundation (project No. 18-73-00071). ; Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:158540 Serial 5205  
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Author (down) Marchetti, A.; Saniz, R.; Krishnan, D.; Rabbachin, L.; Nuyts, G.; De Meyer, S.; Verbeeck, J.; Janssens, K.; Pelosi, C.; Lamoen, D.; Partoens, B.; De Wael, K. pdf  url
doi  openurl
  Title Unraveling the Role of Lattice Substitutions on the Stabilization of the Intrinsically Unstable Pb2Sb2O7Pyrochlore: Explaining the Lightfastness of Lead Pyroantimonate Artists’ Pigments Type A1 Journal article
  Year 2020 Publication Chemistry Of Materials Abbreviated Journal Chem Mater  
  Volume 32 Issue 7 Pages 2863-2873  
  Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract The pyroantimonate pigments Naples yellow and lead tin antimonate yellow are recognized as some of the most stable synthetic yellow pigments in the history of art. However, this exceptional lightfastness is in contrast with experimental evidence suggesting that this class of mixed oxides is of semiconducting nature. In this study the electronic structure and light-induced behavior of the lead pyroantimonate pigments were determined by means of a combined multifaceted analytical and computational approach (photoelectrochemical measurements, UV-vis diffuse reflectance spectroscopy, STEM-EDS, STEM-HAADF, and density functional theory calculations). The results demonstrate both the semiconducting nature and the lightfastness of these pigments. Poor optical absorption and minority carrier mobility are the main properties responsible for the observed stability. In addition, novel fundamental insights into the role played by Na atoms in the stabilization of the otherwise intrinsically unstable Pb2Sb2O7 pyrochlore were obtained.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000526394000016 Publication Date 2020-04-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 8.6 Times cited 8 Open Access OpenAccess  
  Notes Universiteit Antwerpen; Belgian Federal Science Policy Office; Approved Most recent IF: 8.6; 2020 IF: 9.466  
  Call Number EMAT @ emat @c:irua:168819 Serial 6363  
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Author (down) Marazzi, E.; Ghojavand, A.; Pirard, J.; Petretto, G.; Charlier, J.-C.; Rignanese, G.-M. pdf  doi
openurl 
  Title Modeling symmetric and defect-free carbon schwarzites into various zeolite templates Type A1 Journal article
  Year 2023 Publication Carbon Abbreviated Journal  
  Volume 215 Issue Pages 118385-118389  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Recently, a process has been proposed for generating negatively-curved carbon schwarzites via zeolite-templating (Braun et al., 2018). However, the proposed process leads to atomistic models which are not very symmetric and often rather defective. In the present work, an improved generation approach is developed, by imposing symmetry constraints, which systematically leads to defect-free, hence more stable, schwarzites. The stability of the newly predicted symmetric schwarzites is also compared to that of other carbon nanostructures (in particular carbon nanotubes – CNTs), which could also be accommodated within the same templates. Our results suggest that only a few of these (such as FAU, SBT and SBS) can fit schwarzites more stable than CNTs. Our predictions could help experimentalists in the crucial choice of the template for the challenging synthesis of schwarzites. Furthermore, being highly symmetric and stable phases, the models could also be synthesized by means of other experimental procedures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001078649800001 Publication Date 2023-09-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:200314 Serial 9057  
Permanent link to this record
 

 
Author (down) Mao, J.; Milovanović, S.P.; Andelkovic, M.; Lai, X.; Cao, Y.; Watanabe, K.; Taniguchi, T.; Covaci, L.; Peeters, F.M.; Geim, A.K.; Jiang, Y.; Andrei, E.Y. pdf  doi
openurl 
  Title Evidence of flat bands and correlated states in buckled graphene superlattices Type A1 Journal article
  Year 2020 Publication Nature Abbreviated Journal Nature  
  Volume 584 Issue 7820 Pages 215-220  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract Two-dimensional atomic crystals can radically change their properties in response to external influences, such as substrate orientation or strain, forming materials with novel electronic structure(1-5). An example is the creation of weakly dispersive, 'flat' bands in bilayer graphene for certain 'magic' angles of twist between the orientations of the two layers(6). The quenched kinetic energy in these flat bands promotes electron-electron interactions and facilitates the emergence of strongly correlated phases, such as superconductivity and correlated insulators. However, the very accurate fine-tuning required to obtain the magic angle in twisted-bilayer graphene poses challenges to fabrication and scalability. Here we present an alternative route to creating flat bands that does not involve fine-tuning. Using scanning tunnelling microscopy and spectroscopy, together with numerical simulations, we demonstrate that graphene monolayers placed on an atomically flat substrate can be forced to undergo a buckling transition(7-9), resulting in a periodically modulated pseudo-magnetic field(10-14), which in turn creates a 'post-graphene' material with flat electronic bands. When we introduce the Fermi level into these flat bands using electrostatic doping, we observe a pseudogap-like depletion in the density of states, which signals the emergence of a correlated state(15-17). This buckling of two-dimensional crystals offers a strategy for creating other superlattice systems and, in particular, for exploring interaction phenomena characteristic of flat bands. Buckled monolayer graphene superlattices are found to provide an alternative to twisted bilayer graphene for the study of flat bands and correlated states in a carbon-based material.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000559831500012 Publication Date 2020-08-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-0836 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 64.8 Times cited 75 Open Access Not_Open_Access  
  Notes ; ; Approved Most recent IF: 64.8; 2020 IF: 40.137  
  Call Number UA @ admin @ c:irua:171150 Serial 6513  
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Author (down) Mao, J.; Jiang, Y.; Moldovan, D.; Li, G.; Watanabe, K.; Taniguchi, T.; Masir, M.R.; Peeters, F.M.; Andrei, E.Y. doi  openurl
  Title Realization of a tunable artificial atom at a supercritically charged vacancy in graphene Type A1 Journal article
  Year 2016 Publication Nature physics Abbreviated Journal Nat Phys  
  Volume 12 Issue 12 Pages 545-549  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Graphene’s remarkable electronic properties have fuelled the vision of a graphene-based platform for lighter, faster and smarter electronics and computing applications. One of the challenges is to devise ways to tailor graphene’s electronic properties and to control its charge carriers. Here we show that a single-atom vacancy in graphene can stably host a local charge and that this charge can be gradually built up by applying voltage pulses with the tip of a scanning tunnelling microscope. The response of the conduction electrons in graphene to the local charge is monitored with scanning tunnelling and Landau level spectroscopy, and compared to numerical simulations. As the charge is increased, its interaction with the conduction electrons undergoes a transition into a supercritical regime where itinerant electrons are trapped in a sequence of quasi-bound states which resemble an artificial atom. The quasi-bound electron states are detected by a strong enhancement of the density of states within a disc centred on the vacancy site which is surrounded by halo of hole states. We further show that the quasi-bound states at the vacancy site are gate tunable and that the trapping mechanism can be turned on and off, providing a mechanism to control and guide electrons in graphene.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000377475700011 Publication Date 2016-02-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1745-2473 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 22.806 Times cited 93 Open Access  
  Notes ; Funding was provided by DOE-FG02-99ER45742 (STM/STS), NSF DMR 1207108 (fabrication and characterization). Theoretical work supported by ESF-EUROCORES-EuroGRAPHENE, FWO-VI and Methusalem programme of the Flemish government. We thank V. F. Libisch, M. Pereira and E. Rossi for useful discussions. ; Approved Most recent IF: 22.806  
  Call Number c:irua:134210 Serial 4011  
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Author (down) Man, L.F.; Xu, W.; Xiao, Y.M.; Wen, H.; Ding, L.; Van Duppen, B.; Peeters, F.M. url  doi
openurl 
  Title Terahertz magneto-optical properties of graphene hydrodynamic electron liquid Type A1 Journal article
  Year 2021 Publication Physical Review B Abbreviated Journal Phys Rev B  
  Volume 104 Issue 12 Pages 125420  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The discovery of the hydrodynamic electron liquid (HEL) in graphene [D. Bandurin et al., Science 351, 1055 (2016) and J. Crossno et al., Science 351, 1058 (2016)] has marked the birth of the solid-state HEL which can be probed near room temperature in a table-top setup. Here we examine the terahertz (THz) magneto-optical (MO) properties of a graphene HEL. Considering the case where the magnetic length l(B) = root h/eB is comparable to the mean-free path l(ee) for electron-electron interaction in graphene, the MO conductivities are obtained by taking a momentum balance equation approach on the basis of the Boltzmann equation. We find that when l(B) similar to l(ee), the viscous effect in a HEL can weaken significantly the THz MO effects such as cyclotron resonance and Faraday rotation. The upper hybrid and cyclotron resonance magnetoplasmon modes omega(+/-) are also obtained through the RPA dielectric function. The magnetoplasmons of graphene HEL at large wave-vector regime are affected by the viscous effect, and results in red-shifts of the magnetoplasmon frequencies. We predict that the viscosity in graphene HEL can affect strongly the magneto-optical and magnetoplasmonic properties, which can be verified experimentally.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000704419300004 Publication Date 2021-09-15  
  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 1 Open Access OpenAccess  
  Notes Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:182518 Serial 7029  
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Author (down) Maistrenko, Y.L.; Vasylenko, A.; Sudakov, O.; Levchenko, R.; Maistrenko, V.L. doi  openurl
  Title Cascades of multiheaded chimera states for coupled phase oscillators Type A1 Journal article
  Year 2014 Publication International journal of bifurcation and chaos in applied sciences and engineering Abbreviated Journal Int J Bifurcat Chaos  
  Volume 24 Issue 8 Pages 1440014  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Chimera state is a recently discovered dynamical phenomenon in arrays of nonlocally coupled oscillators, that displays a self-organized spatial pattern of coexisting coherence and incoherence. We discuss the appearance of the chimera states in networks of phase oscillators with attractive and with repulsive interactions, i.e. when the coupling respectively favors synchronization or works against it. By systematically analyzing the dependence of the spatiotemporal dynamics on the level of coupling attractivity/repulsivity and the range of coupling, we uncover that different types of chimera states exist in wide domains of the parameter space as cascades of the states with increasing number of intervals of irregularity, so-called chimera's heads. We report three scenarios for the chimera birth: (1) via saddle-node bifurcation on a resonant invariant circle, also known as SNIC or SNIPER, (2) via blue-sky catastrophe, when two periodic orbits, stable and saddle, approach each other creating a saddle-node periodic orbit, and (3) via homoclinic transition with complex multistable dynamics including an “eight-like” limit cycle resulting eventually in a chimera state.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Singapore Editor  
  Language Wos 000341494900015 Publication Date 2014-08-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0218-1274;1793-6551; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.329 Times cited Open Access  
  Notes Approved Most recent IF: 1.329; 2014 IF: 1.078  
  Call Number UA @ lucian @ c:irua:119303 Serial 285  
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Author (down) Magnus, W.; Nelissen, K. pdf  doi
openurl 
  Title Quantum diffusion: A simple, exactly solvable model Type A1 Journal article
  Year 2015 Publication Physica: A : theoretical and statistical physics Abbreviated Journal Physica A  
  Volume 417 Issue 417 Pages 96-101  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We propose a simple quantum mechanical model describing the time dependent diffusion current between two fermion reservoirs that were initially disconnected and characterized by different densities or chemical potentials. The exact, analytical solution of the model yields the transient behavior of the coupled fermion systems evolving to a final steady state, whereas the long-time behavior is determined by a power law rather than by exponential decay. Similar results are obtained for the entropy production which is proportional to the diffusion current. (C) 2014 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000345721800011 Publication Date 2014-09-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0378-4371; ISBN Additional Links UA library record; WoS full record  
  Impact Factor 2.243 Times cited Open Access  
  Notes ; ; Approved Most recent IF: 2.243; 2015 IF: 1.732  
  Call Number c:irua:122170 Serial 2777  
Permanent link to this record
 

 
Author (down) Magnus, W.; Lemmens, L.; Brosens, F. pdf  doi
openurl 
  Title Quantum canonical ensemble : a projection operator approach Type A1 Journal article
  Year 2017 Publication Physica: A : theoretical and statistical physics Abbreviated Journal Physica A  
  Volume 482 Issue Pages 1-13  
  Keywords A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT)  
  Abstract Knowing the exact number of particles N, and taking this knowledge into account, the quantum canonical ensemble imposes a constraint on the occupation number operators. The constraint particularly hampers the systematic calculation of the partition function and any relevant thermodynamic expectation value for arbitrary but fixed N. On the other hand, fixing only the average number of particles, one may remove the above constraint and simply factorize the traces in Fock space into traces over single-particle states. As is well known, that would be the strategy of the grand-canonical ensemble which, however, comes with an additional Lagrange multiplier to impose the average number of particles. The appearance of this multiplier can be avoided by invoking a projection operator that enables a constraint-free computation of the partition function and its derived quantities in the canonical ensemble, at the price of an angular or contour integration. Introduced in the recent past to handle various issues related to particle-number projected statistics, the projection operator approach proves beneficial to a wide variety of problems in condensed matter physics for which the canonical ensemble offers a natural and appropriate environment. In this light, we present a systematic treatment of the canonical ensemble that embeds the projection operator into the formalism of second quantization while explicitly fixing N, the very number of particles rather than the average. Being applicable to both bosonic and fermionic systems in arbitrary dimensions, transparent integral representations are provided for the partition function Z(N) and the Helmholtz free energy F-N as well as for two- and four-point correlation functions. The chemical potential is not a Lagrange multiplier regulating the average particle number but can be extracted from FN+1 – F-N, as illustrated for a two-dimensional fermion gas. (C) 2017 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos 000405885500001 Publication Date 2017-04-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0378-4371 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.243 Times cited 1 Open Access  
  Notes ; ; Approved Most recent IF: 2.243  
  Call Number UA @ lucian @ c:irua:145145 Serial 4722  
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Author (down) Magnus, W.; Carrillo-Nunez, H.; Sorée, B. isbn  openurl
  Title Transport in nanostructures Type H3 Book chapter
  Year 2011 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords H3 Book chapter; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Pan Stanford Place of Publication S.l. Editor  
  Language Wos Publication Date 0000-00-00  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN 9789814364027 Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:93075 Serial 3724  
Permanent link to this record
 

 
Author (down) Magnus, W.; Brosens, F.; Sorée, B. doi  openurl
  Title Modeling drive currents and leakage currents : a dynamic approach Type A1 Journal article
  Year 2009 Publication Journal of computational electronics Abbreviated Journal J Comput Electron  
  Volume 8 Issue 3/4 Pages 307-323  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems  
  Abstract The dynamics of electrons and holes propagating through the nano-scaled channels of modern semiconductor devices can be seen as a widespread manifestation of non-equilibrium statistical physics and its ruling principles. In this respect both the devices that are pushing conventional CMOS technology towards the final frontiers of Moores law and the upcoming set of alternative, novel nanostructures grounded on entirely new concepts and working principles, provide an almost unlimited playground for assessing physical models and numerical techniques emerging from classical and quantum mechanical non-equilibrium theory. In this paper we revisit the Boltzmann as well as the WignerBoltzmann equation which offers a valuable platform to study transport of charge carriers taking part in drive currents. We focus on a numerical procedure that regained attention recently as an alternative tool to solve the time-dependent Boltzmann equation for inhomogeneous systems, such as the channel regions of field-effect transistors, and we discuss its extension to the WignerBoltzmann equation. Furthermore, we pay attention to the calculation of tunneling leakage currents. The latter typically occurs in nano-scaled transistors when part of the carrier distribution sustaining the drive current is found to tunnel into the gate due the presence of an ultra-thin insulating barrier separating the gate from the channel region. In particular, we discuss the paradox related to the very existence of leakage currents established by electrons occupying quasi-bound states, while the (real) wave functions of the latter cannot carry net currents. Finally, we describe a simple model to resolve the paradox as well as to estimate gate currents provided the local carrier generation rates largely exceed the tunneling rates.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication S.l. Editor  
  Language Wos 000208236100009 Publication Date 2009-09-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1569-8025;1572-8137; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.526 Times cited 4 Open Access  
  Notes Approved Most recent IF: 1.526; 2009 IF: NA  
  Call Number UA @ lucian @ c:irua:89503 Serial 2110  
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Author (down) Magnus, W.; Brosens, F.; Sorée, B. url  doi
openurl 
  Title Time dependent transport in 1D micro- and nanostructures: solving the Boltzmann and Wigner-Boltzmann equations Type A1 Journal article
  Year 2009 Publication Journal of physics : conference series Abbreviated Journal  
  Volume 193 Issue 1 Pages 012004,1-012004,4  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems  
  Abstract For many decades the Boltzmann distribution function has been used to calculate the non-equilibrium properties of mobile particles undergoing the combined action of various scattering mechanisms and externally applied force fields. When the latter give rise to the occurrence of inhomogeneous potential profiles across the region through which the particles are moving, the numerical solution of the Boltzmann equation becomes a highly complicated task. In this work we highlight a particular algorithm that can be used to solve the time dependent Boltzmann equation as well as its quantum mechanical extension, the WignerBoltzmann equation. As an illustration, we show the calculated distribution function describing electrons propagating under the action of both a uniform and a pronouncedly non-uniform electric field.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000277100400004 Publication Date 2009-11-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1742-6596; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 2 Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:82861 Serial 3667  
Permanent link to this record
 

 
Author (down) Magnus, W.; Brosens, F. pdf  url
doi  openurl
  Title Occupation numbers in a quantum canonical ensemble : a projection operator approach Type A1 Journal article
  Year 2019 Publication Physica: A : theoretical and statistical physics Abbreviated Journal Physica A  
  Volume 518 Issue 518 Pages 253-264  
  Keywords A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT)  
  Abstract Recently, we have used a projection operator to fix the number of particles in a second quantization approach in order to deal with the canonical ensemble. Having been applied earlier to handle various problems in nuclear physics that involve fixed particle numbers, the projector formalism was extended to grant access as well to quantum-statistical averages in condensed matter physics, such as particle densities and correlation functions. In this light, the occupation numbers of the subsequent single-particle energy eigenstates are key quantities to be examined. The goal of this paper is (1) to provide a sound extension of the projector formalism directly addressing the occupation numbers as well as the chemical potential, and (2) to demonstrate how the emerging problems related to numerical instability for fermions can be resolved to obtain the canonical statistical quantities for both fermions and bosons. (C) 2018 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000456359200021 Publication Date 2018-11-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0378-4371 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.243 Times cited 1 Open Access  
  Notes ; ; Approved Most recent IF: 2.243  
  Call Number UA @ admin @ c:irua:157468 Serial 5223  
Permanent link to this record
 

 
Author (down) Magalhães Cunha, S. url  openurl
  Title Wave-packet dynamics and electronic transport properties in 2D materials Type Doctoral thesis
  Year 2022 Publication Abbreviated Journal  
  Volume Issue Pages 219 p.  
  Keywords Doctoral thesis; Condensed Matter Theory (CMT)  
  Abstract This piece of work is twofold. First, the time evolution of wave-packets in 2D systems is analyzed by the Split-Operator technique in three different scenarios: in multilayer phosphorene, the transient oscillations in the time-dependent average of position and momentum were observed due to the zitterbewegung effect, and the wave packet propagates non-uniformly along the space deforming itself into an elliptical shape. These results were corroborated by the Green’s function formalism except for large values of the wave-vector and long times; in 2D semiconductor quantum wires (QWs) with anisotropic effective masses and different angle orientations with respect to the anisotropic axis. We have shown that the greater this angle, the smaller is the energy levels spacing implying in an increase of the accessible electronic states. Additionally, for non-null magnetic field, the quantum Hall edge states are significantly affected by the edge orientation. In the anisotropic case damped oscillations in the average values of velocity in both x and y directions where obtained. Theses oscillations are originated by the QW geometry but also from subwavepackets with different momentum orientations, whereas for isotropic QWs the wavepacket disperses without splitting; in the third scenario the split-operator technique was used to study the Landau levels, the wave packet trajectories and velocities of electrons in graphene at low-energy regime described by a modified Dirac equation where the momentum-operator is written in a generalized form as result of applying the position-dependent translation operator formalism (PDTO). In the second part of this thesis, the electronic and tunneling properties of α − T3 lattices were studied. Electrons in these lattices behave analogous to integer-spin Dirac Fermions. The presence of a third atomic site in the unit cell leads to a flat band in the energy spectrum, providing unique electronic and tunneling properties. The presence of a super-periodic potential and the inclusion of symmetry-breaking terms results in deviations of the atomic equivalence between the atomic sites affecting the Dirac points and the band-gap. Small deviations in the equivalence between the atomic sites and the number of barriers change the transmission properties in these lattices. Additionally, new tunneling regions are possible by adjusting the symmetry between the atomic sites and affect the omnidirectional total transmission called super-Klein tunneling observed in these lattices. We compare those results to the tunneling probabilities through regions where the energy spectrum changes from linear with a middle flat band to a hyperbolic dispersion.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:189191 Serial 7227  
Permanent link to this record
 

 
Author (down) Maes, J.; Hayne, M.; Sidor, Y.; Partoens, B.; Peeters, F.M.; González, Y.; González, L.; Fuster, D.; Garcia, J.M.; Moshchalkov, V.V. url  doi
openurl 
  Title Electron wave-function spillover in self-assembled InAs/InP quantum wires Type A1 Journal article
  Year 2004 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 70 Issue Pages 155311,1-7  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000224855900053 Publication Date 2004-10-19  
  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 43 Open Access  
  Notes Approved Most recent IF: 3.836; 2004 IF: 3.075  
  Call Number UA @ lucian @ c:irua:62435 Serial 994  
Permanent link to this record
 

 
Author (down) Madan, I.; Kusar, P.; Baranov, V.V.; Lu-Dac, M.; Kabanov, V.V.; Mertelj, T.; Mihailovic, D. url  doi
openurl 
  Title Real-time measurement of the emergence of superconducting order in a high-temperature superconductor Type A1 Journal article
  Year 2016 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 93 Issue 22 Pages 224520  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Systems which rapidly evolve through symmetry-breaking transitions on timescales comparable to the fluctuation timescale of the single-particle excitations may behave very differently than under controlled near-ergodic conditions. A real-time investigation with high temporal resolution may reveal insights into the ordering through the transition that are not available in static experiments. We present an investigation of the system trajectory through a normal-to-superconductor transition in a prototype high-temperature superconducting cuprate in which such a situation occurs. Using a multiple pulse femtosecond spectroscopy technique we measure the system trajectory and time evolution of the single-particle excitations through the transition in La1.9Sr0.1CuO4 and compare the data to a simulation based on the time-dependent Ginzburg-Landau theory, using the laser excitation fluence as an adjustable parameter controlling the quench conditions in both experiment and theory. The comparison reveals the presence of significant superconducting fluctuations which precede the transition on short timescales. By including superconducting fluctuations as a seed for the growth of the superconducting order we can obtain a satisfactory agreement of the theory with the experiment. Remarkably, the pseudogap excitations apparently play no role in this process.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos 000378815800003 Publication Date 2016-07-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 5 Open Access  
  Notes ; We wish to acknowledge the useful discussion with T. W. Kibble regarding the importance of a variable quench rate in the experiment. The funding was provided by European Research Council advanced grant TRAJECTORY. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:144701 Serial 4683  
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Author (down) Maciel de Menezes, R. url  openurl
  Title Skyrmionics and magnonics in chiral ferromagnets : from micromagnetic to atomistic control Type Doctoral thesis
  Year 2021 Publication Abbreviated Journal  
  Volume Issue Pages 222 p.  
  Keywords Doctoral thesis; Condensed Matter Theory (CMT)  
  Abstract The precise control of skyrmionics and magnonics in magnetic materials is key to the development of novel spin-based technology and information transport applications. Essentially, the inherent stability of magnetic skyrmions (provided by their topological charge) together with their extremely small size (down to a few nanometers) and the ultralow threshold current necessary to move them in nanostructures are the main advantages of skyrmionics. Not least, magnonics offers lower power consumption compared to electronics and the excitation of high frequency (sub-100~nm wavelength) magnons makes it possible for the creation of nanometric devices for ultrafast information transport. Even though extensive research has been carried out in recent years, the precise manipulation of skyrmions and spin waves (magnons) in nanostructures is not fully mastered and needs to be addressed before making functional skyrmionic and magnonic devices. In this thesis, we reveal multiple alternatives for the manipulation of skyrmions and spin-waves in different materials, such as bulk chiral magnets, heterochiral structures, magnet-supperconductor hybrids and two-dimentional magnetic materials. We make use of a multiscale model to numerically simulate the magnetic states at each considered material, from micromagnetic to atomistic control. We first explore the different nucleation mechanisms, activation energy, and the time evolution of the skyrmion formation in chiral magnetic films, crucial for the realization of skyrmion-based devices. We show that the skyrmion lattice is formed from the conical phase progressively, most probably by the formation of chiral bobbres, followed by the cylindrical growth of individual skyrmions from the film surface. That reflects a rod-like (one-dimensional) nucleation of the skyrmion phase, with an activation barrier of several electronvolts per skyrmion for the case of MnSi (Manganese monosilicide). In addition, we reveal the interesting blinking (creation-annihilation) behavior of skyrmions close to the phase boundary between the conical and skyrmion phases, where we recall that such switching between topologically distinct states has been proposed as a bit operation for information storage. Next, we discuss the motion of ferromagnetic and antiferromagnetic skyrmions in heterochiral magnets. We report the characteristic deflection of ferromagnetic skyrmions when moving across a heterochiral interface, where the extent of such deflection is tuned by the applied spin-polarized current and the magnitude of Dzyaloshinskii-Moriya interaction. Following, we show that the antiferromagnetic skyrmion achieves much higher velocities than its ferromagnetic counterpart, yet experiences far stronger confinement in nanoengineered heterochiral tracks, which reinforces antiferromagnetic skyrmions as a favorable choice for skyrmion-based devices. After that, we study the interesting coupling of magnetic skyrmions and superconducting vortices in magnet-superconductor heterostructures. We perform numerical simulations, based on experimental observations, to demonstrate that the stray field of magnetic skyrmions can nucleate antivortices in an adjacent superconducting film, giving rise to a hybrid topological object, the skyrmion-vortex pair, which harbor promising features for skyrmionics and quantum computing applications. We then explore the manipulation of a single skyrmion-vortex pair when currents are applied into both superconducting and magnetic parts of the heterostructure, which is of importance for the facilitated skyrmion guidance in racetrack applications. Afterwards, we make use of the high tunability of magnetic parameters in two-dimensional magnetic materials to reveal the rich phase diagram of exotic magnetic configurations in magnetic monolayers with suppressed nearest-neighbour exchange, where we show that several unique cycloidal, checkerboard, row-wise and spin-ice states are stabilized by the competition between the second-nearest-neighbor exchange, Dzyaloshinskii-Moriya, and dipolar interactions. Additionally, we show the coexistence of ferromagnetic and antiferromagnetic spin-cycloids, as well as novel types of skyrmions and chiral domain walls. Finally, in the last part of the thesis, we present the spin wave properties in the two-dimensional magnetic materials CrBr$3$ and CrI$3$. Using spin-dynamics simulations parametrized from first principles, we reveal that the spin wave dispersion in such materials can be tuned in a broad range of frequencies by strain-engineering, and that a designed pattern of strain, as well as structural defects (halide vacancies) can be turned useful in the design of spin-wave guides. Lastly, we discuss the realization of magnonic crystals by moiré-periodic modulation of magnetic parameters in van der Waals heterostructures, where we show that the several nanometer small periodicities in such samples are ideal for the interference of terahertz spin waves. Recalling the wide range of possibilities for manipulating spin waves in such two-dimensional materials, we therefore suggest these systems as a front-runner for prospective terahertz magnonic applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:184244 Serial 7019  
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Author (down) Lyu, Y.-Y.; Jiang, J.; Wang, Y.-L.; Xiao, Z.-L.; Dong, S.; Chen, Q.-H.; Milošević, M.V.; Wang, H.; Divan, R.; Pearson, J.E.; Wu, P.; Peeters, F.M.; Kwok, W.-K. url  doi
openurl 
  Title Superconducting diode effect via conformal-mapped nanoholes Type A1 Journal article
  Year 2021 Publication Nature Communications Abbreviated Journal Nat Commun  
  Volume 12 Issue 1 Pages 2703  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract A superconducting diode is an electronic device that conducts supercurrent and exhibits zero resistance primarily for one direction of applied current. Such a dissipationless diode is a desirable unit for constructing electronic circuits with ultralow power consumption. However, realizing a superconducting diode is fundamentally and technologically challenging, as it usually requires a material structure without a centre of inversion, which is scarce among superconducting materials. Here, we demonstrate a superconducting diode achieved in a conventional superconducting film patterned with a conformal array of nanoscale holes, which breaks the spatial inversion symmetry. We showcase the superconducting diode effect through switchable and reversible rectification signals, which can be three orders of magnitude larger than that from a flux-quantum diode. The introduction of conformal potential landscapes for creating a superconducting diode is thereby proven as a convenient, tunable, yet vastly advantageous tool for superconducting electronics. This could be readily applicable to any superconducting materials, including cuprates and iron-based superconductors that have higher transition temperatures and are desirable in device applications. A superconducting diode is dissipationless and desirable for electronic circuits with ultralow power consumption, yet it remains challenging to realize it. Here, the authors achieve a superconducting diode in a conventional superconducting film patterned with a conformal array of nanoscale holes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000658724200018 Publication Date 2021-05-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 12.124 Times cited 23 Open Access OpenAccess  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:179611 Serial 7024  
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