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“Position-dependent effect of non-magnetic impurities on superconducting properties of nanowires”. Zhang L-F, Covaci L, Peeters FM, Europhysics letters 109, 17010 (2015). http://doi.org/10.1209/0295-5075/109/17010
Abstract: Anderson's theorem states that non-magnetic impurities do not change the bulk properties of conventional superconductors. However, as the dimensionality is reduced, the effect of impurities becomes more significant. Here we investigate superconducting nanowires with diameter comparable to the Fermi wavelength $\lambda_F$ (which is less than the superconducting coherence length) by using a microscopic description based on the Bogoliubov-de Gennes method. We find that: 1) impurities strongly affect the superconducting properties, 2) the effect is impurity position dependent, and 3) it exhibits opposite behavior for resonant and off-resonant wire widths. We show that this is due to the interplay between the shape resonances of the order parameter and the subband energy spectrum induced by the lateral quantum confinement. These effects can be used to manipulate the Josephson current, filter electrons by subband and investigate the symmetries of the superconducting subband gaps.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.957
Times cited: 7
DOI: 10.1209/0295-5075/109/17010
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“Pentagonal monolayer crystals of carbon, boron nitride, and silver azide”. Yagmurcukardes M, Sahin H, Kang J, Torun E, Peeters FM, Senger RT, Journal of applied physics 118, 104303 (2015). http://doi.org/10.1063/1.4930086
Abstract: In this study, we present a theoretical investigation of structural, electronic, and mechanical properties of pentagonal monolayers of carbon (p-graphene), boron nitride (p-B2N4 and p-B4N2), and silver azide (p-AgN3) by performing state-of-the-art first principles calculations. Our total energy calculations suggest feasible formation of monolayer crystal structures composed entirely of pentagons. In addition, electronic band dispersion calculations indicate that while p-graphene and p-AgN3 are semiconductors with indirect bandgaps, p-BN structures display metallic behavior. We also investigate the mechanical properties (in-plane stiffness and the Poisson's ratio) of four different pentagonal structures under uniaxial strain. p-graphene is found to have the highest stiffness value and the corresponding Poisson's ratio is found to be negative. Similarly, p-B2N4 and p-B4N2 have negative Poisson's ratio values. On the other hand, the p-AgN3 has a large and positive Poisson's ratio. In dynamical stability tests based on calculated phonon spectra of these pentagonal monolayers, we find that only p-graphene and p-B2N4 are stable, but p-AgN3 and p-B4N2 are vulnerable against vibrational excitations.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.068
Times cited: 79
DOI: 10.1063/1.4930086
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Schoeters B (2015) An ab initio study of the properties of doped semiconducting nanwires. Antwerpen
Keywords: Doctoral thesis; Condensed Matter Theory (CMT)
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“Significant effect of stacking on the electronic and optical properties of few-layer black phosphorus”. Çakir D, Sevik C, Peeters FM, Physical review : B : condensed matter and materials physics 92, 165406 (2015). http://doi.org/10.1103/PhysRevB.92.165406
Abstract: The effect of the number of stacking layers and the type of stacking on the electronic and optical properties of bilayer and trilayer black phosphorus are investigated by using first-principles calculations within the framework of density functional theory. We find that inclusion of many-body effects (i.e., electron-electron and electron-hole interactions) modifies strongly both the electronic and optical properties of black phosphorus. While trilayer black phosphorus with a particular stacking type is found to be a metal by using semilocal functionals, it is predicted to have an electronic band gap of 0.82 eV when many-body effects are taken into account within the G(0)W(0) scheme. Though different stacking types result in similar energetics, the size of the band gap and the optical response of bilayer and trilayer phosphorene are very sensitive to the number of layers and the stacking type. Regardless of the number of layers and the type of stacking, bilayer and trilayer black phosphorus are direct band gap semiconductors whose band gaps vary within a range of 0.3 eV. Stacking arrangements that are different from the ground state structure in both bilayer and trilayer black phosphorus exhibit significant modified valence bands along the zigzag direction and result in larger hole effective masses. The optical gap of bilayer (trilayer) black phosphorus varies by 0.4 (0.6) eV when changing the stacking type. The calculated binding energy of the bound exciton hardly changes with the type of stacking and is found to be 0.44 (0.30) eV for bilayer (trilayer) phosphorous.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 127
DOI: 10.1103/PhysRevB.92.165406
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Somers W (2015) Atomic scale simulations of the interactions of plasma species on nickel catalyst surfaces. Antwerpen
Keywords: Doctoral thesis; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
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“MULTEM : a new multislice program to perform accurate and fast electron diffraction and imaging simulations using graphics processing units with CUDA”. Lobato I, Van Dyck D, Ultramicroscopy 156, 9 (2015). http://doi.org/10.1016/j.ultramic.2015.04.016
Abstract: The main features and the GPU implementation of the MULTEM program are presented and described. This new program performs accurate and fast multislice simulations by including higher order expansion of the multislice solution of the high energy Schrodinger equation, the correct subslicing of the three-dimensional potential and top-bottom surfaces. The program implements different kinds of simulation for CTEM, STEM, ED, PED, CBED, ADF-TEM and ABF-HC with proper treatment of the spatial and temporal incoherences. The multislice approach described here treats the specimen as amorphous material which allows a straightforward implementation of the frozen phonon approximation. The generalized transmission function for each slice is calculated when is needed and then discarded. This allows us to perform large simulations that can include millions of atoms and keep the computer memory requirements to a reasonable level. (C) 2015 Elsevier B.V. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Impact Factor: 2.843
Times cited: 32
DOI: 10.1016/j.ultramic.2015.04.016
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“Quantifying inflow and RANS turbulence model form uncertainties for wind engineering flows”. Gorle C, Garcia Sánchez C, Iaccarino G, Journal of wind engineering and industrial aerodynamics
T2 –, 6th International Symposium on Computational Wind Engineering (CWE), JUN 08-12, 2014, Hamburg, GERMANY 144, 202 (2015). http://doi.org/10.1016/j.jweia.2015.03.025
Abstract: Reynolds-averaged Navier-Stokes (RANS) simulations are often used in the wind engineering practice for the analysis of turbulent bluff body flows. An approach that allows identifying the uncertainty related to the use of reduced-order turbulence models in RANS simulations would significantly increase the confidence in the use of simulation results as a basis for design decisions. In the present study we apply a strategy that enables quantifying these uncertainties by introducing perturbations in the Reynolds stress tensor to simulations of the flow in downtown Oklahoma City. The method is combined with a framework to quantify uncertainties in the inflow wind direction and intensity, and the final result of the UQ approach is compared to field measurement data for the velocity at 13 locations in the downtown area. (C) 2015 Elsevier Ltd. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.049
Times cited: 22
DOI: 10.1016/j.jweia.2015.03.025
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“Tuning the magnetic anisotropy in single-layer crystal structures”. Torun E, Sahin H, Bacaksiz C, Senger RT, Peeters FM, Physical review : B : condensed matter and materials physics 92, 104407 (2015). http://doi.org/10.1103/PhysRevB.92.104407
Abstract: The effect of an applied electric field and the effect of charging are investigated on themagnetic anisotropy (MA) of various stable two-dimensional (2D) crystals such as graphene, FeCl2, graphone, fluorographene, and MoTe2 using first-principles calculations. We found that themagnetocrystalline anisotropy energy of Co-on-graphene and Os-doped-MoTe2 systems change linearly with electric field, opening the possibility of electric field tuningMAof these compounds. In addition, charging can rotate the easy-axis direction ofCo-on-graphene andOs-doped-MoTe2 systems from the out-of-plane (in-plane) to in-plane (out-of-plane) direction. The tunable MA of the studied materials is crucial for nanoscale electronic technologies such as data storage and spintronics devices. Our results show that controlling the MA of the mentioned 2D crystal structures can be realized in various ways, and this can lead to the emergence of a wide range of potential applications where the tuning and switching of magnetic functionalities are important.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 37
DOI: 10.1103/PhysRevB.92.104407
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“An eco-friendly soft template synthesis of mesostructured silica-carbon nanocomposites for acid catalysis”. Zhong R, Peng L, de Clippel F, Gommes C, Goderis B, Ke X, Van Tendeloo G, Jacobs PA, Sels BF, ChemCatChem 7, 3047 (2015). http://doi.org/10.1002/cctc.201500728
Abstract: The synthesis of ordered mesoporous silica-carbon composites was explored by employing TEOS and sucrose as the silica and carbon precursor respectively, and the triblock copolymer F127 as a structure-directing agent via an evaporation-induced self-assembly (EISA) process. It is demonstrated that the synthesis procedures allow for control of the textural properties and final composition of these silica-carbon nanocomposites via adjustment of the effective SiO2/C weight ratio. Characterization by SAXS, N-2 physisorption, HRTEM, TGA, and C-13 and Si-29 solid-state MAS NMR show a 2D hexagonal mesostructure with uniform large pore size ranging from 5.2 to 7.6nm, comprising of separate carbon phases in a continuous silica phase. Ordered mesoporous silica and non-ordered porous carbon can be obtained by combustion of the pyrolyzed nanocomposites in air or etching with HF solution, respectively. Sulfonic acid groups can be readily introduced to such kind of silica-carbon nanocomposites by a standard sulfonation procedure with concentrated sulfuric acid. Excellent acid-catalytic activities and selectivities for the dimerization of styrene to produce 1,3-diphenyl-1-butene and dimerization of -methylstyrene to unsaturated dimers were demonstrated with the sulfonated materials.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 4.803
Times cited: 13
DOI: 10.1002/cctc.201500728
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“The role of ions in plasma catalytic carbon nanotube growth : a review”. Neyts EC, Frontiers of Chemical Science and Engineering 9, 154 (2015). http://doi.org/10.1007/s11705-015-1515-5
Abstract: While it is well-known that the plasma-enhanced catalytic chemical vapor deposition (PECVD) of carbon nanotubes (CNTs) offers a number of advantages over thermal CVD, the influence of the various individual contributing factors is not well understood. Especially the role of ions is unclear, since ions in plasmas are generally associated with sputtering rather than with growing a material. Even so, various studies have demonstrated the beneficial effects of ion bombardment during the growth of CNTs. This review looks at the role of the ions in plasma-enhanced CNT growth as deduced from both experimental and simulation studies. Specific attention is paid to the beneficial effects of ion bombardment. Based on the available literature, it can be concluded that ions can be either beneficial or detrimental for carbon nanotube growth, depending on the exact conditions and the control over the growth process.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 1.712
Times cited: 8
DOI: 10.1007/s11705-015-1515-5
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“TiS3 nanoribbons : width-independent band gap and strain-tunable electronic properties”. Kang J, Sahin H, Ozaydin HD, Senger RT, Peeters FM, Physical review : B : condensed matter and materials physics 92, 075413 (2015). http://doi.org/10.1103/PhysRevB.92.075413
Abstract: The electronic properties, carrier mobility, and strain response of TiS3 nanoribbons (TiS3 NRs) are investigated by first-principles calculations. We found that the electronic properties of TiS3 NRs strongly depend on the edge type (a or b). All a-TiS3 NRs are metallic with a magnetic ground state, while b-TiS3 NRs are direct band gap semiconductors. Interestingly, the size of the band gap and the band edge position are almost independent of the ribbon width. This feature promises a constant band gap in a b-TiS3 NR with rough edges, where the ribbon width differs in different regions. The maximum carrier mobility of b-TiS3 NRs is calculated by using the deformation potential theory combined with the effective mass approximation and is found to be of the order 10(3) cm(2) V-1 s(-1). The hole mobility of the b-TiS3 NRs is one order of magnitude lower, but it is enhanced compared to the monolayer case due to the reduction in hole effective mass. The band gap and the band edge position of b-TiS3 NRs are quite sensitive to applied strain. In addition we investigate the termination of ribbon edges by hydrogen atoms. Upon edge passivation, the metallic and magnetic features of a-TiS3 NRs remain unchanged, while the band gap of b-TiS3 NRs is increased significantly. The robust metallic and ferromagnetic nature of a-TiS3 NRs is an essential feature for spintronic device applications. The direct, width-independent, and strain-tunable band gap, as well as the high carrier mobility, of b-TiS3 NRs is of potential importance in many fields of nanoelectronics, such as field-effect devices, optoelectronic applications, and strain sensors.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 55
DOI: 10.1103/PhysRevB.92.075413
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“Structural and phononic characteristics of nitrogenated holey graphene”. Sahin H, Physical review : B : condensed matter and materials physics 92, 085421 (2015). http://doi.org/10.1103/PhysRevB.92.085421
Abstract: Recent experimental studies showed that formation of a two-dimensional crystal structure of nitrogenated holey graphene (NHG) is possible. Similar to graphene, NHGs have an atomically thin and strong crystal structure. Using first-principles calculations, we investigate the structural, phononic, and thermal properties of monolayer NHG crystal. Our charge analysis reveals that the charged holey sites of NHG provide a reactive ground for further functionalization by adatoms or molecules. We also found that similar to graphene, the NHG structure has quite high-frequency phonon modes and the presence of nitrogen atoms leads to the emergence of additional vibrational modes. Our phonon analysis reveals the presence of three characteristic Raman-active modes of NHG. Furthermore, the analysis of constant-volume heat capacity showed that the NHG structure has a linear temperature dependence in the low-temperature region. The strong lattice structure and unique thermal properties of the NHG crystal structure are desirable in nanoscale device applications.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 49
DOI: 10.1103/PhysRevB.92.085421
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“Chainlike transitions in Wigner crystals : sequential versus nonsequential”. Galvan-Moya, Misko VR, Peeters FM, Physical review : B : condensed matter and materials physics 92, 064112 (2015). http://doi.org/10.1103/PhysRevB.92.064112
Abstract: The structural transitions of the ground state of a system of repulsively interacting particles confined in a quasi-one-dimensional channel, and the effect of the interparticle interaction as well as the functional form of the confinement potential on those transitions are investigated. Although the nonsequential ordering of transitions (non-SOT), i.e., the 1 – 2 – 4 – 3 – 4 – 5 – 6 – ... sequence of chain configurations with increasing density, is widely robust as predicted in a number of theoretical studies, the sequential ordering of transitions (SOT), i.e., the 1 – 2 – 3 – 4 – 5 – 6 – ... chain, is found as the ground state for long-ranged interparticle interaction and hard-wall-like confinement potentials. We found an energy barrier between every two different phases around its transition point, which plays an important role in the preference of the system to follow either a SOT or a non-SOT. However, that preferential transition requires also the stability of the phases during the transition. Additionally, we analyze the effect of a small structural disorder on the transition between the two phases around its transition point. Our results show that a small deformation of the triangular structure changes dramatically the picture of the transition between two phases, removing in a considerable region the non-SOT in the system. This feature could explain the fact that the non-SOT is, up to now, not observed in experimental systems, and suggests a more advanced experimental setup to detect the non-SOT.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 3
DOI: 10.1103/PhysRevB.92.064112
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Grujić, MM (2015) Manifestations of intrinsic and induced magnetic properties of graphene nanostructures. University of Antwerp, Faculty of Sciences, Department of Physics, Antwerp
Keywords: Doctoral thesis; Condensed Matter Theory (CMT)
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Govaerts K (2015) First-principles study of homologous series of layered Bi-Sb-Te-Se and Sn-O structures. Antwerpen
Keywords: Doctoral thesis; Electron microscopy for materials research (EMAT)
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Zhang L (2015) Effects of quantum confinement in nanoscale superconductors : from electronic density of states to vortex matter. Antwerpen
Keywords: Doctoral thesis; Condensed Matter Theory (CMT)
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Sarmadian N (2015) Identification of thin-film photovoltaic cell materials based on high-throughput first-principles calculations. Antwerpen
Keywords: Doctoral thesis; Electron microscopy for materials research (EMAT)
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de Backer A (2015) Quantitative atomic resolution electron microscopy using advanced statistical techniques. Antwerpen
Keywords: Doctoral thesis; Electron microscopy for materials research (EMAT)
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Sivek J (2015) First-principles characterization and functionalization of graphene-like materials. Antwerpen
Keywords: Doctoral thesis; Condensed Matter Theory (CMT)
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da Costa DR (2015) Transport and confinement in monolayer and bilayer graphene nanostructures with different edges, interfaces and potentials. Antwerpen
Keywords: Doctoral thesis; Condensed Matter Theory (CMT)
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Amin-Ahmadi B (2015) Adanced TEM investigation of the elementary plsticity mechanisms in palladium thin films at the nano scale. Antwerpen
Keywords: Doctoral thesis; Electron microscopy for materials research (EMAT)
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Roose D (2015) Magnetic resonance imaging and electron microscopy of iron oxide particles in the brain. Universiteit Antwerpen, Faculteit Farmaceutische, Biomedische en Diergeneeskundige Wetenschappen, Departement Biomedische Wetenschappen, Antwerpen
Keywords: Doctoral thesis; Electron microscopy for materials research (EMAT)
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Martí,nez Alanis GT (2015) Quantitative model-based high angle annular dark field scanning transmission electron microscopy. Antwerpen
Keywords: Doctoral thesis; Electron microscopy for materials research (EMAT); Engineering Management (ENM)
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“Emergent phenomena in multicomponent superconductivity: an introduction to the focus issue”. Milošević, MV, Perali A, Superconductor Science &, Technology 28, 060201 (2015). http://doi.org/10.1088/0953-2048/28/6/060201
Keywords: A1 Journal article; CMT
Impact Factor: 2.878
Times cited: 41
DOI: 10.1088/0953-2048/28/6/060201
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“Sidestream deammonification on thermal hydrolysis process digestate : strategies to overcome nitritation inhibition”. Zhang Q, De Clippeleir H, Al-Omari A, Wett B, Vlaeminck SE, Murthy S, , 11 p.
T2 (2015)
Keywords: P3 Proceeding; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
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“Energy efficient treatment of A-stage effluent : pilot-scale experiences with short-cut nitrogen removal”. Seuntjens D, Bundervoet BLM, Mollen H, De Mulder C, Wypkema E, Verliefde A, Nopens I, Colsen JGM, Vlaeminck SE, , 10 p.
T2 (2015)
Keywords: P3 Proceeding; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
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“Some like it hot : perspectives for thermophilic nitrogen removal”. Vlaeminck SE, Courtens ENP, Vandekerckhove TGL, Boon N, , 4 p.
T2 (2015)
Keywords: P3 Proceeding; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
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“The age of wastewater mining : selection for sludge with a maximum capture potential for organics in a high-rate contact stabilization system”. Meerburg FA, Boon N, Van Winckel T, Pauwels K, Vlaeminck SE, , 3 p.
T2 (2015)
Keywords: P3 Proceeding; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
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“Water and nutrient recovery from combined urine and grey water treatment in Space”. Lindeboom REF, Clauwaert P, Alloul A, Coessens W, Christiaens M, Vanoppen M, Rabaey K, Verliefde ARD, Vlaeminck SE, , 3 p.
T2 (2015)
Keywords: P3 Proceeding; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
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“The nitrogen and phosphorus budget of Flanders : a tool for efficient resource management”. Coppens J, Meers E, Boon N, Buysse J, Vlaeminck SE, , 3 p.
T2 (2015)
Keywords: P3 Proceeding; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
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