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Author Petrovic, M.D.; Peeters, F.M.; Chaves, A.; Farias, G.A. pdf  doi
openurl 
  Title Conductance maps of quantum rings due to a local potential perturbation Type A1 Journal article
  Year 2013 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 25 Issue 49 Pages (down) 495301-495309  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We performed a numerical simulation of the dynamics of a Gaussian shaped wavepacket inside a small sized quantum ring, smoothly connected to two leads and exposed to a perturbing potential of a biased atomic force microscope tip. Using the Landauer formalism, we calculated conductance maps of this system in the case of single and two subband transport. We explain the main features in the conductance maps as due to the AFM tip influence on the wavepacket phase and amplitude. In the presence of an external magnetic field, the tip modifies the phi(0) periodic Aharonov-Bohm oscillation pattern into a phi(0)/2 periodic Al'tshuler-Aronov-Spivak oscillation pattern. Our results in the case of multiband transport suggest tip selectivity to higher subbands, making them more observable in the total  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000327181400002 Publication Date 2013-11-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 12 Open Access  
  Notes ; This work was supported by the Methusalem programme of the Flemish government, the CNPq-FWO bilateral programme and PNPD and FUNCAP/PRONEX grants. ; Approved Most recent IF: 2.649; 2013 IF: 2.223  
  Call Number UA @ lucian @ c:irua:112694 Serial 478  
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Author Masir, M.R.; Vasilopoulos, P.; Peeters, F.M. pdf  doi
openurl 
  Title Kronig-Penney model of scalar and vector potentials in graphene Type A1 Journal article
  Year 2010 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 22 Issue 46 Pages (down) 465302,1-465302,10  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We consider a one-dimensional (1D) superlattice (SL) on graphene consisting of very high and very thin (δ-function) magnetic and potential barriers with zero average potential and zero magnetic field. We calculate the energy spectrum analytically, study it in different limiting cases, and determine the condition under which an electron beam incident on an SL is highly collimated along its direction. In the absence of the magnetic SL the collimation is very sensitive to the value of W/Ws and is optimal for W/Ws = 1, where W is the distance between the positive and negative barriers and L = W + Ws is the size of the unit cell. In the presence of only the magnetic SL the collimation decreases and the symmetry of the spectrum around ky is broken for W/Ws\neq 1 . In addition, a gap opens which depends on the strength of the magnetic field. We also investigate the effect of spatially separated potential and magnetic δ-function barriers and predict a better collimation in specific cases.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000283838800004 Publication Date 2010-11-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 41 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-VI), the Belgian Science Policy (IAP), and the Canadian NSERC Grant No. OGP0121756. ; Approved Most recent IF: 2.649; 2010 IF: 2.332  
  Call Number UA @ lucian @ c:irua:85807 Serial 1767  
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Author Chen, Y.; Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M. pdf  doi
openurl 
  Title Superconducting nanowires: quantum confinement and spatially dependent Hartree-Fock potential Type A1 Journal article
  Year 2009 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 21 Issue 43 Pages (down) 435701,1-435701,7  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract It is well known that, in bulk, the solution of the Bogoliubovde Gennes equations is the same whether or not the HartreeFock term is included. Here the HartreeFock potential is position independent and so gives the same contribution to both the single-electron energies and the Fermi level (the chemical potential). Thus, the single-electron energies measured from the Fermi level (they control the solution) stay the same. This is not the case for nanostructured superconductors, where quantum confinement breaks the translational symmetry and results in a position-dependent HartreeFock potential. In this case its contribution to the single-electron energies depends on the relevant quantum numbers. We numerically solved the Bogoliubovde Gennes equations with the HartreeFock term for a clean superconducting nanocylinder and found a shift of the curve representing the thickness-dependent oscillations of the critical superconducting temperature to larger diameters.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000270642700012 Publication Date 2009-10-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 12 Open Access  
  Notes Approved Most recent IF: 2.649; 2009 IF: 1.964  
  Call Number UA @ lucian @ c:irua:79162 Serial 3360  
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Author Pizzochero, M.; Leenaerts, O.; Partoens, B.; Martinazzo, R.; Peeters, F.M. pdf  url
doi  openurl
  Title Hydrogen adsorption on nitrogen and boron doped graphene Type A1 Journal article
  Year 2015 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 27 Issue 27 Pages (down) 425502  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Hydrogen adsorption on boron and nitrogen doped graphene is investigated in detail by means of first-principles calculations. A comprehensive study is performed of the structural, electronic, and magnetic properties of chemisorbed hydrogen atoms and atom pairs near the dopant sites. The main effect of the substitutional atoms is charge doping which is found to greatly affect the adsorption process by increasing the binding energy at the sites closest to the substitutional species. It is also found that doping does not induce magnetism despite the odd number of electrons per atom introduced by the foreign species, and that it quenches the paramagnetic response of chemisorbed H atoms on graphene. Overall, the effects are similar for B and N doping, with only minor differences in the adsorption energetics due to different sizes of the dopant atoms and the accompanying lattice distortions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Wos 000362573500008 Publication Date 2015-10-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 20 Open Access  
  Notes This work was supported by the Flemish Science Foundation (FWO-Vl). MP gratefully acknowledges the Condensed Matter Theory group at Universiteit Antwerpen for the hospitality during his stay. Approved Most recent IF: 2.649; 2015 IF: 2.346  
  Call Number c:irua:128759 Serial 3971  
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Author Abdullah, H.M.; Van Duppen, B.; Zarenia, M.; Bahlouli, H.; Peeters, F.M. pdf  doi
openurl 
  Title Quantum transport across van der Waals domain walls in bilayer graphene Type A1 Journal article
  Year 2017 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 29 Issue 42 Pages (down) 425303  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Bilayer graphene can exhibit deformations such that the two graphene sheets are locally detached from each other resulting in a structure consisting of domains with different van der Waals inter-layer coupling. Here we investigate how the presence of these domains affects the transport properties of bilayer graphene. We derive analytical expressions for the transmission probability, and the corresponding conductance, across walls separating different inter-layer coupling domains. We find that the transmission can exhibit a valley-dependent layer asymmetry and that the domain walls have a considerable effect on the chiral tunnelling properties of the charge carriers. We show that transport measurements allow one to obtain the strength with which the two layers are coupled. We perform numerical calculations for systems with two domain walls and find that the availability of multiple transport channels in bilayer graphene significantly modifies the conductance dependence on inter-layer potential asymmetry.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000410958400001 Publication Date 2017-07-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 15 Open Access  
  Notes ; HMA and HB acknowledge the Saudi Center for Theoretical Physics (SCTP) for their generous support and the support of KFUPM under physics research group projects RG1502-1 and RG1502-2. This work is supported by the Flemish Science Foundation (FWO-VI) by a post-doctoral fellowship (BVD). ; Approved Most recent IF: 2.649  
  Call Number UA @ lucian @ c:irua:146664 Serial 4793  
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Author Dabaghmanesh, S.; Saniz, R.; Amini, M.N.; Lamoen, D.; Partoens, B. pdf  doi
openurl 
  Title Perovskite transparent conducting oxides : an ab initio study Type A1 Journal article
  Year 2013 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 25 Issue 41 Pages (down) 415503  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract We present an ab initio study of the electronic structure and of the formation energies of various point defects in BaSnO3 and SrGeO3. We show that La and Y impurities substituting Ba or Sr are shallow donors with a preferred 1 + charge state. These defects have a low formation energy within all the suitable equilibrium growth conditions considered. Oxygen vacancies behave as shallow donors as well, preferring the 2 + charge state. Their formation energies, however, are higher in most growth conditions, indicating a limited contribution to conductivity. The calculated electron effective mass in BaSnO3, with a value of 0.21 me, and the very high mobility reported recently in La-doped BaSnO3 single-crystals, suggest that remarkably low scattering rates can be achieved in the latter. In the case of SrGeO3, our results point to carrier density and mobility values in the low range for typical polycrystalline TCOs, in line with experiment.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000324920400011 Publication Date 2013-09-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 17 Open Access  
  Notes FWO;Hercules Approved Most recent IF: 2.649; 2013 IF: 2.223  
  Call Number UA @ lucian @ c:irua:110495 Serial 2574  
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Author Nowak, M.P.; Szafran, B.; Peeters, F.M. doi  openurl
  Title Manipulation of two-electron states by the electric field in stacked self-assembled dots Type A1 Journal article
  Year 2008 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 20 Issue 39 Pages (down) 395225,1-395225,14  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract A pair of electrons in vertically stacked self-assembled quantum dots is studied and the singlettriplet energy splitting is calculated in an external electric field using the configuration-interaction method. We show that for double quantum dots the dependence of the singlet energy levels on the electric field involves multiple avoided crossings of three energy levels. The exchange interaction, i.e., the energy difference of the lowest triplet and lowest singlet states, can be tuned by an electric field in a wide range of several tens of meV. For electric fields exceeding a threshold value the exchange interaction becomes a linear function of the field when the two electrons in the singlet state start to occupy the same dot. We also consider non-symmetric confinement, non-perfectly aligned dots, in horizontal as well as vertical field orientation. In a stack of three vertically coupled dots the depth of the confinement in the central dot can be used to enhance the exchange interaction. For a deeper central dot the dependence of the exchange interaction on the electric field is anomalousit initially decreases when the field is applied in both directions parallel and antiparallel to the axis of the stack. Such a behavior is never observed for a pair of quantum dots.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000259034200032 Publication Date 2008-09-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 5 Open Access  
  Notes Approved Most recent IF: 2.649; 2008 IF: 1.900  
  Call Number UA @ lucian @ c:irua:76592 Serial 1940  
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Author Abdullah, H.M.; Bahlouli, H.; Peeters, F.M.; Van Duppen, B. pdf  doi
openurl 
  Title Confined states in graphene quantum blisters Type A1 Journal article
  Year 2018 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 30 Issue 38 Pages (down) 385301  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Bilayer graphene samples may exhibit regions where the two layers are locally delaminated forming a so-called quanttun blister in the graphene sheet. Electron and hole states can be confined in this graphene quantum blisters (GQB) by applying a global electrostatic bias. We scrutinize the electronic properties of these confined states under the variation of interlayer bias, coupling, and blister's size. The spectra display strong anti-crossings due to the coupling of the confined states on upper and lower layers inside the blister. These spectra are layer localized where the respective confined states reside on either layer or equally distributed. For finite angular momentum, this layer localization can be at the edge of the blister and corresponds to degenerate modes of opposite momenta. Furthermore, the energy levels in GQB exhibit electron-hole symmetry that is sensitive to the electrostatic bias. Finally, we demonstrate that confinement in GQB persists even in the presence of a variation in the interlayer coupling.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000443135000001 Publication Date 2018-08-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 6 Open Access  
  Notes ; HMA and HB acknowledge the Saudi Center for Theoretical Physics (SCTP) for their generous support and the support of KFUPM under physics research group projects RG1502-1 and RG1502-2. This work is supported by the Flemish Science Foundation (FWO-Vl) by a post-doctoral fellowship (BVD). ; Approved Most recent IF: 2.649  
  Call Number UA @ lucian @ c:irua:153620UA @ admin @ c:irua:153620 Serial 5086  
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Author Sena, S.H.R.; Pereira, J.M.; Farias, G.A.; Peeters, F.M.; Costa Filho, R.N. pdf  doi
openurl 
  Title The electronic properties of graphene and graphene ribbons under simple shear strain Type A1 Journal article
  Year 2012 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 24 Issue 37 Pages (down) 375301  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract A tight-binding model is used to study the energy band of graphene and graphene ribbon under simple shear strain. The ribbon consists of lines of carbon atoms in an armchair or zigzag orientation where a simple shear strain is applied in the x-direction keeping the atomic distances in the y-direction unchanged. Such modification in the lattice gives an energy band that differs in several aspects from the one without any shear and with pure shear. The changes in the spectrum depend on the line displacement of the ribbon, and also on the modified hopping parameter. It is also shown that this simple shear strain tunes the electronic properties of both graphene and graphene ribbon, opening and closing energy gaps for different displacements of the system. The modified density of states is also shown.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000308202700011 Publication Date 2012-08-14  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 15 Open Access  
  Notes ; This work was supported by CNPq (RNCF), the National Council for the Improvement of Higher Education (CAPES), the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the bilateral program between Flanders and Brazil. ; Approved Most recent IF: 2.649; 2012 IF: 2.355  
  Call Number UA @ lucian @ c:irua:101838 Serial 1000  
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Author Wang, J.; Shin, Y.; Gauquelin, N.; Yang, Y.; Lee, C.; Jannis, D.; Verbeeck, J.; Rondinelli, J.M.; May, S.J. url  doi
openurl 
  Title Physical properties of epitaxial SrMnO2.5−δFγoxyfluoride films Type A1 Journal article
  Year 2019 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 31 Issue 36 Pages (down) 365602  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract Recently, topotactic fluorination has become an alternative way of doping epitaxial perovskite oxides through anion substitution to engineer their electronic properties instead of the more commonly used cation substitution. In this work, epitaxial oxyfluoride SrMnO2.5−δ F γ films were synthesized via topotactic fluorination of SrMnO2.5 films using polytetrafluoroethylene as the fluorine source. Oxidized SrMnO3 films were also prepared for comparison with the fluorinated samples. The F content, probed by x-ray photoemission spectroscopy, was systematically controlled by adjusting fluorination conditions. Electronic transport measurements reveal that increased F content (up to γ  =  0.14) systematically increases the electrical resistivity, despite the nominal electron-doping induced by F substitution for O in these films. In contrast, oxidized SrMnO3 exhibits a decreased resistivity and conduction activation energy. A blue-shift of optical absorption features occurs with increasing F content. Density functional theory calculations indicate that F acts as a scattering center for electronic transport, controls the observed weak ferromagnetic behavior of the films, and reduces the inter-band optical transitions in the manganite films. These results stand in contrast to bulk electron-doped La1−x Ce x MnO3, illustrating how aliovalent anionic substitutions can yield physical behavior distinct from A-site substituted perovskites with the same nominal B-site oxidation states.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000472232000002 Publication Date 2019-09-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 5 Open Access  
  Notes Work at Drexel was supported by the National Science Foundation (NSF), grant number CMMI-1562223. Thin film synthesis utilized deposition instrumentation acquired through an Army Research Office DURIP grant (W911NF-14-1-0493). Y.S and J.M.R. were supported by NSF (Grant No. DMR-1454688). Calculations were performed using the QUEST HPC Facility at Northwestern, the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by NSF Grant No. ACI-1053575, and the Center for Nanoscale Materials (Carbon Cluster). Use of the Center for Nanoscale Materials, an Office of Science user facility, was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. J.V. and N. G. acknowledge funding from a GOA project “Solarpaint” of the University of Antwerp. D.J. acknowledges funding from FWO project G093417N from the Flemish fund for scientific research. Approved Most recent IF: 2.649  
  Call Number EMAT @ emat @UA @ admin @ c:irua:161174 Serial 5293  
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Author Moors, K.; Sorée, B.; Magnus, W. pdf  doi
openurl 
  Title Validity criteria for Fermi's golden rule scattering rates applied to metallic nanowires Type A1 Journal article
  Year 2016 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 28 Issue 28 Pages (down) 365302  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Fermi's golden rule underpins the investigation of mobile carriers propagating through various solids, being a standard tool to calculate their scattering rates. As such, it provides a perturbative estimate under the implicit assumption that the effect of the interaction Hamiltonian which causes the scattering events is sufficiently small. To check the validity of this assumption, we present a general framework to derive simple validity criteria in order to assess whether the scattering rates can be trusted for the system under consideration, given its statistical properties such as average size, electron density, impurity density et cetera. We derive concrete validity criteria for metallic nanowires with conduction electrons populating a single parabolic band subjected to different elastic scattering mechanisms: impurities, grain boundaries and surface roughness.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000380754400013 Publication Date 2016-07-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 2 Open Access  
  Notes ; ; Approved Most recent IF: 2.649  
  Call Number UA @ lucian @ c:irua:135011 Serial 4274  
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Author Varley, J.B.; Peelaers, H.; Janotti, A.; van de Walle, C.G. pdf  doi
openurl 
  Title Hydrogenated cation vacancies in semiconducting oxides Type A1 Journal article
  Year 2011 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 23 Issue 33 Pages (down) 334212,1-334212,9  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first-principles calculations we have studied the electronic and structural properties of cation vacancies and their complexes with hydrogen impurities in SnO2, In2O3 and β-Ga2O3. We find that cation vacancies have high formation energies in SnO2 and In2O3 even in the most favorable conditions. Their formation energies are significantly lower in β-Ga2O3. Cation vacancies, which are compensating acceptors, strongly interact with H impurities resulting in complexes with low formation energies and large binding energies, stable up to temperatures over 730 °C. Our results indicate that hydrogen has beneficial effects on the conductivity of transparent conducting oxides: it increases the carrier concentration by acting as a donor in the form of isolated interstitials, and by passivating compensating acceptors such as cation vacancies; in addition, it potentially enhances carrier mobility by reducing the charge of negatively charged scattering centers. We have also computed vibrational frequencies associated with the isolated and complexed hydrogen, to aid in the microscopic identification of centers observed by vibrational spectroscopy.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000294060600014 Publication Date 2011-08-04  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 125 Open Access  
  Notes ; We gratefully acknowledge useful discussions with M D Mc-Cluskey, O Bierwagen and J Speck. The work was supported by the NSF MRSEC Program (DMR05-20415), the Flemish Science Foundation (FWO-VI), the Belgian American Educational Foundation, and by Saint-Gobain Research, and made use of computing facilities at CNSI (NSF grant No. CHE-0321368), TeraGrid and TACC (NSF grant No. DMR070072N), and NERSC (DOE Office of Science Contract No. DE-AC02-05CH11231). ; Approved Most recent IF: 2.649; 2011 IF: 2.546  
  Call Number UA @ lucian @ c:irua:92415 Serial 1534  
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Author Bekaert, J.; Bringmans, L.; Milošević, M.V. pdf  url
doi  openurl
  Title Ginzburg-Landau surface energy of multiband superconductors : derivation and application to selected systems Type A1 Journal article
  Year 2023 Publication Journal of physics : condensed matter Abbreviated Journal  
  Volume 35 Issue 32 Pages (down) 325602-325610  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We determine the energy of an interface between a multiband superconducting and a normal half-space, in presence of an applied magnetic field, based on a multiband Ginzburg-Landau (GL) approach. We obtain that the multiband surface energy is fully determined by the critical temperature, electronic densities of states, and superconducting gap functions associated with the different band condensates. This furthermore yields an expression for the thermodynamic critical magnetic field, in presence of an arbitrary number of contributing bands. Subsequently, we investigate the sign of the surface energy as a function of material parameters, through numerical solution of the GL equations. Here, we consider two distinct cases: (i) standard multiband superconductors with attractive interactions, and (ii) a three-band superconductor with a chiral ground state with phase frustration, arising from repulsive interband interactions. Furthermore, we apply this approach to several prime examples of multiband superconductors, such as metallic hydrogen and MgB2, based on microscopic parameters obtained from first-principles calculations.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000986281900001 Publication Date 2023-05-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 2.7 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 2.7; 2023 IF: 2.649  
  Call Number UA @ admin @ c:irua:196664 Serial 8875  
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Author Masir, M.R.; Vasilopoulos, P.; Peeters, F.M. pdf  doi
openurl 
  Title Graphene in inhomogeneous magnetic fields : bound, quasi-bound and scattering states Type A1 Journal article
  Year 2011 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 23 Issue 31 Pages (down) 315301,1-315301,14  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The electron states in graphene-based magnetic dot and magnetic ring structures and combinations of both are investigated. The corresponding spectra are studied as a function of the radii, the strengths of the inhomogeneous magnetic field and of a uniform background field, the strength of an electrostatic barrier and the angular momentum quantum number. In the absence of an external magnetic field we have only long-lived quasi-bound and scattering states and we assess their influence on the density of states. In addition, we consider elastic electron scattering by a magnetic dot, whose average B vanishes, and show that the Hall and longitudinal resistivities, as a function of the Fermi energy, exhibit a pronounced oscillatory structure due to the presence of quasi-bound states. Depending on the dot parameters this oscillatory structure differs substantially for energies below and above the first Landau level.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000293008900002 Publication Date 2011-07-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 38 Open Access  
  Notes ; This work was supported by the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE, the Canadian NSERC grant no. OGP0121756 and the Belgian Science Policy (IAP). We acknowledge discussions and correspondence with Professor A Matulis. ; Approved Most recent IF: 2.649; 2011 IF: 2.546  
  Call Number UA @ lucian @ c:irua:91176 Serial 1372  
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Author Wang, S.; Tian, H.; Sun, M. pdf  doi
openurl 
  Title Valley-polarized and enhanced transmission in graphene with a smooth strain profile Type A1 Journal article
  Year 2023 Publication Journal of physics : condensed matter Abbreviated Journal  
  Volume 35 Issue 30 Pages (down) 304002-304013  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We explore the influence of strain on the valley-polarized transmission of graphene by employing the wave-function matching and the non-equilibrium Green's function technique. When the transmission is along the armchair direction, we show that the valley polarization and transmission can be improved by increasing the width of the strained region and increasing (decreasing) the extensional strain in the armchair (zigzag) direction. It is noted that the shear strain does not affect transmission and valley polarization. Furthermore, when we consider the smooth strain barrier, the valley-polarized transmission can be enhanced by increasing the smoothness of the strain barrier. We hope that our finding can shed new light on constructing graphene-based valleytronic and quantum computing devices by solely employing strain.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000977124700001 Publication Date 2023-04-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.7 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 2.7; 2023 IF: 2.649  
  Call Number UA @ admin @ c:irua:196718 Serial 8953  
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Author Oncel, N.; Çakir, D.; Dil, J.H.; Slomski, B.; Landolt, G. pdf  doi
openurl 
  Title Angle-resolved synchrotron photoemission and density functional theory on the iridium modified Si(111) surface Type A1 Journal article
  Year 2014 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 26 Issue 28 Pages (down) 285501  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The physical and electronic properties of the Ir modified Si(1 1 1) surface have been investigated with the help of angle resolved photoemission spectroscopy and density functional theory. The surface consists of Ir-ring clusters that form a root 7 x root 7 -R19.1 degrees reconstruction. A comparison between the measured and calculated band structure of the system reveals that the dispersions of the projected bulk states and the states originating from '1x1' domains are heavily modified due to Umklapp scattering from the surface Brillouin zone. Density of states calculations show that Ir-ring clusters contribute to the states in the vicinity of the Fermi level.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000338830300019 Publication Date 2014-06-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 4 Open Access  
  Notes ; This work was partially supported by the National Science Foundation (DMR-1306101), North Dakota EPSCoR office (NSF grant #EPS-814442), the University of North Dakota and the Swiss National Science Foundation. Computer resources used in this work partially provided by Computational Research Center (HPC-Linux cluster) at UND and TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). ; Approved Most recent IF: 2.649; 2014 IF: 2.346  
  Call Number UA @ lucian @ c:irua:118636 Serial 114  
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Author Rakhimov, K.Y.; Chaves, A.; Farias, G.A.; Peeters, F.M. pdf  doi
openurl 
  Title Wavepacket scattering of Dirac and Schrödinger particles on potential and magnetic barriers Type A1 Journal article
  Year 2011 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 23 Issue 27 Pages (down) 275801,1-275801,16  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We investigate the dynamics of a charged particle moving in a graphene layer and in a two-dimensional electron gas, where it obeys the Dirac and the Schrödinger equations, respectively. The charge carriers are described as Gaussian wavepackets. The dynamics of the wavepackets is studied numerically by solving both quantum-mechanical and relativistic equations of motion. The scattering of such wavepackets by step-like magnetic and potential barriers is analysed for different values of wavepacket energy and width. We find: (1) that the average position of the wavepacket does not coincide with the classical trajectory, and (2) that, for slanted incidence, the path of the centre of mass of the wavepacket does not have to penetrate the barrier during the scattering process. Trembling motion of the charged particle in graphene is observed in the absence of an external magnetic field and can be enhanced by a substrate-induced mass term.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000291993600009 Publication Date 2011-06-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 32 Open Access  
  Notes ; Discussions with A Matulis are gratefully acknowledged. KR is beneficiary of a mobility grant from the Belgian Federal Science Policy Office, co-funded by the European Commission and was supported in part by a grant of the Third World Academy of Sciences (ref. 09-188 RG/PHYS/AS-I). In addition, this work was financially supported by CNPq, under contract NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES, the Bilateral programme between Flanders and Brazil, the joint project CNPq-FWO, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 2.649; 2011 IF: 2.546  
  Call Number UA @ lucian @ c:irua:90880 Serial 3908  
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Author Vanherck, J.; Sorée, B.; Magnus, W. pdf  doi
openurl 
  Title Anisotropic bulk and planar Heisenberg ferromagnets in uniform, arbitrarily oriented magnetic fields Type A1 Journal article
  Year 2018 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 30 Issue 27 Pages (down) 275801  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Today, further downscaling of mobile electronic devices poses serious problems, such as energy consumption and local heat dissipation. In this context, spin wave majority gates made of very thin ferromagnetic films may offer a viable alternative. However, similar downscaling of magnetic thin films eventually enforces the latter to operate as quasi-2D magnets, the magnetic properties of which are not yet fully understood, especially those related to anisotropies and external magnetic fields in arbitrary directions. To this end, we have investigated the behaviour of an easy-plane and easy-axis anisotropic ferromagnet-both in two and three dimensions-subjected to a uniform magnetic field, applied along an arbitrary direction. In this paper, a spin-1/2 Heisenberg Hamiltonian with anisotropic exchange interactions is solved using double-time temperature-dependent Green's functions and the Tyablikov decoupling approximation. We determine various magnetic properties such as the Curie temperature and the magnetization as a function of temperature and the applied magnetic field, discussing the impact of the system's dimensionality and the type of anisotropy. The magnetic reorientation transition taking place in anisotropic Heisenberg ferromagnets is studied in detail. Importantly, spontaneous magnetization is found to be absent for easy-plane 2D spin systems with short range interactions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000434980600001 Publication Date 2018-05-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited Open Access  
  Notes ; ; Approved Most recent IF: 2.649  
  Call Number UA @ lucian @ c:irua:151945UA @ admin @ c:irua:151945 Serial 5012  
Permanent link to this record
 

 
Author Croitoru, M.D.; Shanenko, A.A.; Kaun, C.C.; Peeters, F.M. pdf  doi
openurl 
  Title Ultra-small metallic grains : effect of statistical fluctuations of the chemical potential on superconducting correlations and vice versa Type A1 Journal article
  Year 2012 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 24 Issue 27 Pages (down) 275701  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Superconducting correlations in an isolated metallic grain are governed by the interplay between two energy scales: the mean level spacing delta and the bulk pairing gap Delta(0), which are strongly influenced by the position of the chemical potential with respect to the closest single-electron level. In turn superconducting correlations affect the position of the chemical potential. Within the parity projected BCS model we investigate the probability distribution of the chemical potential in a superconducting grain with randomly distributed single-electron levels. Taking into account statistical fluctuations of the chemical potential due to the pairing interaction, we find that such fluctuations have a significant impact on the critical level spacing delta(c) at which the superconducting correlations cease: the critical ratio delta(c)/Delta(0) at which superconductivity disappears is found to be increased.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000305653100012 Publication Date 2012-06-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 9 Open Access  
  Notes ; This work was supported by the European Community under the Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR), the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF network INSTANS. MDC and AAS are grateful to A Vagov for stimulating discussions. ; Approved Most recent IF: 2.649; 2012 IF: 2.355  
  Call Number UA @ lucian @ c:irua:100280 Serial 3793  
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Author Chen, Y.; Shanenko, A.A.; Croitoru, M.D.; Peeters, F.M. pdf  doi
openurl 
  Title Quantum cascades in nano-engineered superconductors : geometrical, thermal and paramagnetic effects Type A1 Journal article
  Year 2012 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 24 Issue 26 Pages (down) 265702  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The effect of a parallel magnetic field on the orbital motion of electrons in high-quality superconducting nanowires resulting in a superconductor-to-normal transition which occurs through a cascade of jumps in the order parameter as a function of the magnetic field. Such cascades originate from the transverse size quantization that splits the conduction band into a series of subbands. Here, based on a numerical solution of the Bogoliubov-de Gennes equations for a hollow nanocylinder, we investigate how the quantum-size cascades depend on the confining geometry, i.e., by changing the cylinder radius R and its thickness d we cover the range from the nanowire-like to the nanofilm-like regime. The cascades are shown to become much less pronounced when increasing R/d, i.e., when the nanofilm-like regime is approached. When the temperature is non-zero they are thermally smoothed. This includes the spin-magnetic-field interaction which reduces the critical (depairing) parallel magnetic field H-c,H-parallel to but does not have any qualitative effect on the quantum cascades. From our calculations it is seen that the paramagnetic limiting field H-par significantly exceeds H-c,H-parallel to even in extremely narrow nanocylinders, i.e., when R, d are down to a few nanometers, and H-c,H-parallel to is only about 10% larger when switching-off the spin-magnetic-field interaction in this case. Both characteristic fields, H-c,H-parallel to and H-par, exhibit pronounced quantum-size oscillations. We demonstrate that the quantum cascades and the quantum-size oscillations survive in the presence of surface roughness.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000305640800014 Publication Date 2012-06-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 6 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-VI) and the ESF-AQDJJ network. MDC acknowledges the support of the EU Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR). ; Approved Most recent IF: 2.649; 2012 IF: 2.355  
  Call Number UA @ lucian @ c:irua:100281 Serial 2773  
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Author Gonzalez-Garcia, A.; Lopez-Perez, W.; Gonzalez-Hernandez, R.; Rodriguez, J.A.; Milošević, M.V.; Peeters, F.M. pdf  url
doi  openurl
  Title Tunable 2D-gallium arsenide and graphene bandgaps in a graphene/GaAs heterostructure : an ab initio study Type A1 Journal article
  Year 2019 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 31 Issue 26 Pages (down) 265502  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The bandgap behavior of 2D-GaAs and graphene have been investigated with van der Waals heterostructured into a yet unexplored graphene/GaAs bilayer, under both uniaxial stress along c axis and different planar strain distributions. The 2D-GaAs bandgap nature changes from Gamma-K indirect in isolated monolayer to Gamma-Gamma direct in graphene/GaAs bilayer. In the latter, graphene exhibits a bandgap of 5 meV. The uniaxial stress strongly affects the graphene electronic bandgap, while symmetric in-plane strain does not open the bandgap in graphene. Nevertheless, it induces remarkable changes on the GaAs bandgap-width around the Fermi level. However, when applying asymmetric in-plane strain to graphene/GaAs, the graphene sublattice symmetry is broken, and the graphene bandgap is open at the Fermi level to a maximum width of 814 meV. This value is much higher than that reported for just graphene under asymmetric strain. The Gamma-Gamma direct bandgap of GaAs remains unchanged in graphene/ GaAs under different types of applied strain. The analyses of phonon dispersion and the elastic constants yield the dynamical and mechanical stability of the graphene/GaAs system, respectively. The calculated mechanical properties for bilayer heterostructure are better than those of their constituent monolayers. This finding, together with the tunable graphene bandgap not only by the strength but also by the direction of the strain, enhance the potential for strain engineering of ultrathin group-III-V electronic devices hybridized by graphene.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000465887100001 Publication Date 2019-03-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 6 Open Access  
  Notes ; This work has been carried out with the financial support of Universidad del Norte and Colciencias (Administrative Department of Science, Technology and Research of Colombia) under Convocatoria 712-Convocatoria para proyectos de investigacion en Ciencias Basicas, ano 2015, Cod: 121571250192, Contrato 110-216; and the partial support of DGAPA-UNAM project IN114817-3. The authors gratefully acknowledge the support from the High Performance Computing core facility CalcUA and the TOPBOF project at the University of Antwerp, Belgium; DGTIC-UNAM under project LANCAD-UNAM-DGTIC-150, and the computing time granted on the supercomputer Mogon at Johannes Gutenberg University Mainz (hpc.uni-mainz.de). ; Approved Most recent IF: 2.649  
  Call Number UA @ admin @ c:irua:160216 Serial 5236  
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Author de de Meux, A.J.; Pourtois, G.; Genoe, J.; Heremans, P. pdf  doi
openurl 
  Title Origin of the apparent delocalization of the conduction band in a high-mobility amorphous semiconductor Type A1 Journal article
  Year 2017 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 29 Issue 25 Pages (down) 255702  
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract In this paper, we show that the apparent delocalization of the conduction band reported from first-principles simulations for the high-mobility amorphous oxide semiconductor InGaZnO4 (a-IGZO) is an artifact induced by the periodic conditions imposed to the model. Given a sufficiently large unit-cell dimension (over 40 angstrom), the conduction band becomes localized. Such a model size is up to four times the size of commonly used models for the study of a-IGZO. This finding challenges the analyses done so far on the nature of the defects and on the interpretation of numerous electrical measurements. In particular, we re-interpret the meaning of the computed effective mass reported so far in literature. Our finding also applies to materials such as SiZnSnO, ZnSnO, InZnSnO, In2O3 or InAlZnO4 whose models have been reported to display a fully delocalized conduction band in the amorphous phase.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000402434900002 Publication Date 2017-02-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 5 Open Access Not_Open_Access  
  Notes Approved Most recent IF: 2.649  
  Call Number UA @ lucian @ c:irua:144183 Serial 4676  
Permanent link to this record
 

 
Author Kong, X.; Li, L.; Peeters, F.M. pdf  doi
openurl 
  Title Graphene-based heterostructures with moire superlattice that preserve the Dirac cone: a first-principles study Type A1 Journal article
  Year 2019 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 31 Issue 25 Pages (down) 255302  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In van der Waals heterostructures consisting of graphene and a substrate, lattice mismatch often leads to a moire pattern with a huge supercell, preventing its treatment within first- principles calculations. Previous theoretical works considered mostly simple stacking models such as AB, AA with straining the lattice of graphene to match that of the substrate. Here, we propose a moire superlattice build from graphene and porous graphene or graphyne like monolayers, having a lower interlayer binding energy, needing little strain in order to match the lattices. In contrast to the results from the simple stacking models, the present ab initio calculations for the moire superlattices show different properties in lattice structure, energy, and band structures. For example, the Dirac cone at the K point is preserved and a linear energy dispersion near the Fermi level is obtained.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000464184300001 Publication Date 2019-03-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 4 Open Access  
  Notes ; This work is supported by the Collaborative Innovation Center of Quantum Matter, the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl) and the FLAG-ERA project TRANS-2D-TMD. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation-Flanders (FWO) and the Flemish Government-department EWI, and the National Supercomputing Center in Tianjin, funded by the Collaborative Innovation Center of Quantum Matter. ; Approved Most recent IF: 2.649  
  Call Number UA @ admin @ c:irua:159314 Serial 5215  
Permanent link to this record
 

 
Author Simchi, H.; Simchi, M.; Fardmanesh, M.; Peeters, F.M. pdf  url
doi  openurl
  Title Phase transition and field effect topological quantum transistor made of monolayer MoS2 Type A1 Journal article
  Year 2018 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 30 Issue 23 Pages (down) 235303  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We study topological phase transitions and topological quantum field effect transistor in monolayer molybdenum disulfide (MoS2) using a two-band Hamiltonian model. Without considering the quadratic (q(2)) diagonal term in the Hamiltonian, we show that the phase diagram includes quantum anomalous Hall effect, quantum spin Hall effect, and spin quantum anomalous Hall effect regions such that the topological Kirchhoff law is satisfied in the plane. By considering the q(2) diagonal term and including one valley, it is shown that MoS2 has a non-trivial topology, and the valley Chern number is non-zero for each spin. We show that the wave function is (is not) localized at the edges when the q(2) diagonal term is added (deleted) to (from) the spin-valley Dirac mass equation. We calculate the quantum conductance of zigzag MoS2 nanoribbons by using the nonequilibrium Green function method and show how this device works as a field effect topological quantum transistor.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000432821600001 Publication Date 2018-04-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 2 Open Access  
  Notes ; ; Approved Most recent IF: 2.649  
  Call Number UA @ lucian @ c:irua:151457UA @ admin @ c:irua:151457 Serial 5035  
Permanent link to this record
 

 
Author Singh, K.; Maignan, A.; Simon, C.; Kumar, S.; Martin, C.; Lebedev, O.; Turner, S.; Van Tendeloo, G. pdf  doi
openurl 
  Title Magnetodielectric CuCr0.5V0.5O2 : an example of a magnetic and dielectric multiglass Type A1 Journal article
  Year 2012 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 24 Issue 22 Pages (down) 226002-226002,4  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)  
  Abstract The complex dielectric susceptibility and spin glass properties of polycrystalline CuCr0.5V 0.5O2 delafossite have been investigated. Electron diffraction, high resolution electron microscopy and electron energy loss spectroscopy show that the Cr3+ and V 3+ magnetic cations are randomly distributed on the triangular network of CdI2-type layers. In contrast to CuCrO2, CuCr0.5V 0.5O2 exhibits two distinctive (magnetic and electric) glassy states evidenced by memory effects in electric and magnetic susceptibilities. A large magnetodielectric coupling is observed at low temperature.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000304873300027 Publication Date 2012-05-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 19 Open Access  
  Notes Approved Most recent IF: 2.649; 2012 IF: 2.355  
  Call Number UA @ lucian @ c:irua:98380 Serial 1916  
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Author da Costa, D.R.; Chaves, A.; Farias, G.A.; Peeters, F.M. pdf  doi
openurl 
  Title Valley filtering in graphene due to substrate-induced mass potential Type A1 Journal article
  Year 2017 Publication Journal of physics : condensed matter Abbreviated Journal  
  Volume 29 Issue 21 Pages (down) 215502  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The interaction of monolayer graphene with specific substrates may break its sublattice symmetry and results in unidirectional chiral states with opposite group velocities in the different Dirac cones (Zarenia et al 2012 Phys. Rev. B 86 085451). Taking advantage of this feature, we propose a valley filter based on a transversal mass kink for low energy electrons in graphene, which is obtained by assuming a defect region in the substrate that provides a change in the sign of the substrate-induced mass and thus creates a non-biased channel, perpendicular to the kink, for electron motion. By solving the time-dependent Schrodinger equation for the tight-binding Hamiltonian, we investigate the time evolution of a Gaussian wave packet propagating through such a system and obtain the transport properties of this graphene-based substrate-induced quantum point contact. Our results demonstrate that efficient valley filtering can be obtained, provided: (i) the electron energy is sufficiently low, i.e. with electrons belonging mostly to the lowest sub-band of the channel, and (ii) the channel length (width) is sufficiently long (narrow). Moreover, even though the transmission probabilities for each valley are significantly affected by impurities and defects in the channel region, the valley polarization in this system is shown to be robust against their presence.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000400092700002 Publication Date 2017-04-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 15 Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:152636 Serial 8730  
Permanent link to this record
 

 
Author Dixit, H.; Saniz, R.; Cottenier, S.; Lamoen, D.; Partoens, B. pdf  doi
openurl 
  Title Electronic structure of transparent oxides with the Tran-Blaha modified Becke-Johnson potential Type A1 Journal article
  Year 2012 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 24 Issue 20 Pages (down) 205503-205503,9  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract We present electronic band structures of transparent oxides calculated using the Tran-Blaha modified Becke-Johnson (TB-mBJ) potential. We studied the basic n-type conducting binary oxides In2O3, ZnO, CdO and SnO2 along with the p-type conducting ternary oxides delafossite CuXO2 (X = Al, Ga, In) and spinel ZnX2O4 (X = Co, Rh, Ir). The results are presented for calculated band gaps and effective electron masses. We discuss the improvements in the band gap determination using TB-mBJ compared to the standard generalized gradient approximation (GGA) in density functional theory (DFT) and also compare the electronic band structure with available results from the quasiparticle GW method. It is shown that the calculated band gaps compare well with the experimental and GW results, although the electron effective mass is generally overestimated.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000303507100009 Publication Date 2012-04-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 113 Open Access  
  Notes Iwt; Fwo Approved Most recent IF: 2.649; 2012 IF: 2.355  
  Call Number UA @ lucian @ c:irua:98222 Serial 1017  
Permanent link to this record
 

 
Author Cukaric, N.A.; Partoens, B.; Tadic, M.Z.; Arsoski, V.V.; Peeters, F.M. pdf  doi
openurl 
  Title The 30-band k . p theory of valley splitting in silicon thin layers Type A1 Journal article
  Year 2016 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 28 Issue 28 Pages (down) 195303  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The valley splitting of the conduction-band states in a thin silicon-on-insulator layer is investigated using the 30-band k . p theory. The system composed of a few nm thick Si layer embedded within thick SiO2 layers is analyzed. The valley split states are found to cross periodically with increasing quantum well width, and therefore the energy splitting is an oscillatory function of the quantum well width, with period determined by the wave vector K-0 of the conduction band minimum. Because the valley split states are classified by parity, the optical transition between the ground hole state and one of those valley split conduction band states is forbidden. The oscillations in the valley splitting energy decrease with electric field and with smoothing of the composition profile between the well and the barrier by diffusion of oxygen from the SiO2 layers to the Si quantum well. Such a smoothing also leads to a decrease of the interband transition matrix elements. The obtained results are well parametrized by the effective two-valley model, but are found to disagree from previous 30-band calculations. This discrepancy could be traced back to the fact that the basis for the numerical solution of the eigenproblem must be restricted to the first Brillouin zone in order to obtain quantitatively correct results for the valley splitting.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000374394700009 Publication Date 2016-04-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 2.649 Times cited Open Access  
  Notes ; This work was supported by the Ministry of Education, Science, and Technological Development of Serbia, the Flemish fund for Scientific Research (FWO-Vl), and the Methusalem programme of the Flemish government. ; Approved Most recent IF: 2.649  
  Call Number UA @ lucian @ c:irua:133610 Serial 4261  
Permanent link to this record
 

 
Author Sivek, J.; Sahin, H.; Partoens, B.; Peeters, F.M. pdf  doi
openurl 
  Title Giant magnetic anisotropy in doped single layer molybdenum disulfide and fluorographene Type A1 Journal article
  Year 2016 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 28 Issue 28 Pages (down) 195301  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Stable monolayer materials based on existing, well known and stable two-dimensional crystal fluorographene and molybdenum disulfide are predicted to exhibit a huge magnetocrystalline anisotropy when functionalized with adsorbed transition metal atoms at vacant sides. Ab initio calculations within the density-functional theory formalism were performed to investigate the adsorption of the transitional metals in a single S (or F) vacancy of monolayer molybdenum disulfide (or fluorographene). We found strong bonding of the transitional metal atoms to the vacant sites with binding energies ranging from 2.5 to 5.2 eV. Our calculations revealed that these systems with adsorbed metal atoms exhibit a magnetic anisotropy, specifically the structures including Os and Ir show a giant magnetocrystalline anisotropy energy of 31-101 meV. Our results demonstrate the possibility of obtaining stable monolayer materials with huge magnetocrystalline anisotropy based on preexisting, well known and stable two-dimensional crystals: fluorographene and molybdenum disulfide. We believe that the results obtained here are useful not only for deeper understanding of the origin of magnetocrystalline anisotropy but also for the design of monolayer optoelectronic devices with novel functionalities.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000374394700007 Publication Date 2016-04-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 7 Open Access  
  Notes Approved Most recent IF: 2.649  
  Call Number UA @ lucian @ c:irua:133611 Serial 4185  
Permanent link to this record
 

 
Author Chen, Y.; Shanenko, A.A.; Perali, A.; Peeters, F.M. pdf  doi
openurl 
  Title Superconducting nanofilms : molecule-like pairing induced by quantum confinement Type A1 Journal article
  Year 2012 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 24 Issue 18 Pages (down) 185701-185701,8  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Quantum confinement of the perpendicular motion of electrons in single-crystalline metallic superconducting nanofilms splits the conduction band into a series of single-electron subbands. A distinctive feature of such a nanoscale multi-band superconductor is that the energetic position of each subband can vary significantly with changing nanofilm thickness, substrate material, protective cover and other details of the fabrication process. It can occur that the bottom of one of the available subbands is situated in the vicinity of the Fermi level. We demonstrate that the character of the superconducting pairing in such a subband changes dramatically and exhibits a clear molecule-like trend, which is very similar to the well-known crossover from the Bardeen-Cooper-Schrieffer regime to Bose-Einstein condensation (BCS-BEC) observed in trapped ultracold fermions. For Pb nanofilms with thicknesses of 4 and 5 monolayers (MLs) this will lead to a spectacular scenario: up to half of all the Cooper pairs nearly collapse, shrinking in the lateral size (parallel to the nanofilm) down to a few nanometers. As a result, the superconducting condensate will be a coherent mixture of almost molecule-like fermionic pairs with ordinary, extended Cooper pairs.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000303500900018 Publication Date 2012-04-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984;1361-648X; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 26 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). AAS thanks A Bianconi, M D Croitoru and A V Vagov for useful discussions. AAS acknowledges the hospitality and fruitful interactions with G C Strinati, P Pieri and D Neilson during his visit to the University of Camerino, supported by the School of Advanced Studies of the University of Camerino. ; Approved Most recent IF: 2.649; 2012 IF: 2.355  
  Call Number UA @ lucian @ c:irua:98223 Serial 3357  
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