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Author | Singh, S.K.; Srinivasan, S.G.; Neek-Amal, M.; Costamagna, S.; van Duin, A.C.T.; Peeters, F.M. | ||||
Title | Thermal properties of fluorinated graphene | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 10 | Pages | 104114-104116 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Large-scale atomistic simulations using the reactive force field approach are implemented to investigate the thermomechanical properties of fluorinated graphene (FG). A set of parameters for the reactive force field potential optimized to reproduce key quantum mechanical properties of relevant carbon-fluorine cluster systems are presented. Molecular dynamics simulations are used to investigate the thermal rippling behavior of FG and its mechanical properties and compare them with graphene, graphane and a sheet of boron nitride. The mean square value of the height fluctuations < h(2)> and the height-height correlation function H(q) for different system sizes and temperatures show that FG is an unrippled system in contrast to the thermal rippling behavior of graphene. The effective Young's modulus of a flake of fluorinated graphene is obtained to be 273 N/m and 250 N/m for a flake of FG under uniaxial strain along armchair and zigzag directions, respectively. DOI: 10.1103/PhysRevB.87.104114 | ||||
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Language | Wos | 000316933500002 | Publication Date | 2013-03-29 | |
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ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 80 | Open Access | |
Notes | ; M.N.-A. is supported by the EU-Marie Curie IIF postdoc Fellowship/299855. This work is supported by the ESF-Eurographene project CONGRAN, the Flemish Science Foundation (FWO-Vl), and the Methusalem Foundation of the Flemish Government. S. G. S. and A.C.T.vD. acknowledge support by the Air Force Office of Scientific Research (AFOSR) under Grant No. FA9550-10-1-0563. ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:108495 | Serial | 3629 | ||
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Author | Sivek, J.; Sahin, H.; Partoens, B.; Peeters, F.M. | ||||
Title | Adsorption and absorption of boron, nitrogen, aluminum, and phosphorus on silicene : stability and electronic and phonon properties | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 8 | Pages | 085444-85448 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Ab initio calculations within the density-functional theory formalism are performed to investigate the chemical functionalization of a graphene-like monolayer of siliconsilicenewith B, N, Al, or P atoms. The structural, electronic, magnetic, and vibrational properties are reported. The most preferable adsorption sites are found to be valley, bridge, valley and hill sites for B, N, Al, and P adatoms, respectively. All the relaxed systems with adsorbed/substituted atoms exhibit metallic behavior with strongly bonded B, N, Al, and P atoms accompanied by an appreciable electron transfer from silicene to the B, N, and P adatom/substituent. The Al atoms exhibit opposite charge transfer, with n-type doping of silicene and weaker bonding. The adatoms/substituents induce characteristic branches in the phonon spectrum of silicene, which can be probed by Raman measurements. Using molecular dynamics, we found that the systems under study are stable up to at least T=500 K. Our results demonstrate that silicene has a very reactive and functionalizable surface. | ||||
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Language | Wos | 000315482900007 | Publication Date | 2013-02-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
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ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 169 | Open Access | |
Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus Marie Curie Fellowship. ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:107071 | Serial | 60 | ||
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Author | Grujić, M.; Tadić, M.; Peeters, F.M. | ||||
Title | Antiferromagnetism in hexagonal graphene structures : rings versus dots | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 8 | Pages | 085434-85436 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Themean-field Hubbard model is used to investigate the formation of the antiferromagnetic phase in hexagonal graphene rings with inner zigzag edges. The outer edge of the ring was taken to be either zigzag or armchair, and we found that both types of structures can have a larger antiferromagnetic interaction as compared with hexagonal dots. This difference could be partially ascribed to the larger number of zigzag edges per unit area in rings than in dots. Furthermore, edge states localized on the inner ring edge are found to hybridize differently than the edge states of dots, which results in important differences in the magnetism of graphene rings and dots. The largest staggered magnetization is found when the outer edge has a zigzag shape. However, narrow rings with armchair outer edge are found to have larger staggered magnetization than zigzag hexagons. The edge defects are shown to have the least effect on magnetization when the outer ring edge is armchair shaped. DOI: 10.1103/PhysRevB.87.085434 | ||||
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Language | Wos | 000315146600005 | Publication Date | 2013-02-20 | |
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 | 29 | Open Access | |
Notes | ; This work was supported by the EuroGRAPHENE programme of the ESF (project CONGRAN), the Serbian Ministry of Education, Science, and Technological Development, and the Flemish Science Foundation (FWO-VI). ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:107661 | Serial | 137 | ||
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Author | Sahin, H.; Peeters, F.M. | ||||
Title | Adsorption of alkali, alkaline-earth, and 3d transition metal atoms on silicene | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 8 | Pages | 085423-85429 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The adsorption characteristics of alkali, alkaline-earth, and transition metal adatoms on silicene, a graphene-like monolayer structure of silicon are analyzed by means of first-principles calculations. In contrast to graphene, interaction between the metal atoms and the silicene surface is quite strong due to its highly reactive buckled hexagonal structure. In addition to structural properties, we also calculate the electronic band dispersion, net magnetic moment, charge transfer, work function, and dipole moment of the metal adsorbed silicene sheets. Alkali metals, Li, Na, and K, adsorb to hollow sites without any lattice distortion. As a consequence of the significant charge transfer from alkalis to silicene, metalization of silicene takes place. Trends directly related to atomic size, adsorption height, work function, and dipole moment of the silicene/alkali adatom system are also revealed. We found that the adsorption of alkaline-earth metals on silicene is entirely different from their adsorption on graphene. The adsorption of Be, Mg, and Ca turns silicene into a narrow gap semiconductor. Adsorption characteristics of eight transition metals Ti, V, Cr, Mn, Fe, Co, Mo, and W are also investigated. As a result of their partially occupied d orbital, transition metals show diverse structural, electronic, and magnetic properties. Upon the adsorption of transition metals, depending on the adatom type and atomic radius, the system can exhibit metal, half-metal, and semiconducting behavior. For all metal adsorbates, the direction of the charge transfer is from adsorbate to silicene, because of its high surface reactivity. Our results indicate that the reactive crystal structure of silicene provides a rich playground for functionalization at nanoscale. DOI: 10.1103/PhysRevB.87.085423 | ||||
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Language | Wos | 000315146500008 | Publication Date | 2013-02-19 | |
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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 | 281 | Open Access | |
Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vl). Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. is supported by a FWO Pegasus Marie Curie Fellowship. ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:107663 | Serial | 62 | ||
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Author | Zhu, J.-J.; Badalyan, S.M.; Peeters, F.M. | ||||
Title | Plasmonic excitations in Coulomb-coupled N-layer graphene structures | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 8 | Pages | 085401-85408 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We study Dirac plasmons and their damping in spatially separated N-layer graphene structures at finite doping and temperatures. The plasmon spectrum consists of one optical excitation with square-root dispersion and N – 1 acoustical excitations with linear dispersion, which are undamped at zero temperature and finite doping within a triangular energy region outside the electron-hole continuum. In the long-wavelength limit the energy and weight of the optical plasmon modes increase, respectively, as the square root and linearly with N in agreement with recent experimental findings. The energy and weight of the upper-lying acoustical branches also increase with N. This increase is strongest for the uppermost acoustical mode, and we find that its energy can exceed at some value of momentum the plasmon energy in an individual graphene sheet. Meanwhile, the energy of the low-lying acoustical branches decreases weakly with N as compared with the single acoustical mode in double-layer graphene structures. Our numerical calculations provide a detailed understanding of the overall behavior of the wave-vector dependence of the optical and acoustical multilayer plasmon modes and show how their dispersion and damping are modified as a function of temperature, interlayer spacing, and inlayer carrier density in (un)balanced graphene multilayer structures. DOI: 10.1103/PhysRevB.87.085401 | ||||
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Language | Wos | 000314682900005 | Publication Date | 2013-02-05 | |
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ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 59 | Open Access | |
Notes | ; This work was supported by the ESF-Eurocores program EuroGRAPHENE (CONGRAN project) and the Flemish Science Foundation (FWO-Vl). ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:107671 | Serial | 2645 | ||
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Author | Arsoski, V.V.; Tadić, M.Z.; Peeters, F.M. | ||||
Title | Strain and band-mixing effects on the excitonic Aharonov-Bohm effect in In(Ga)As/GaAs ringlike quantum dots | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 8 | Pages | 085314-14 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Neutral excitons in strained axially symmetric In(Ga)As/GaAs quantum dots with a ringlike shape are investigated. Similar to experimental self-assembled quantum rings, the analyzed quantum dots have volcano-like shapes. The continuum mechanical model is employed to determine the strain distribution, and the single-band envelope function approach is adopted to compute the electron states. The hole states are determined by the axially symmetric multiband Luttinger-Kohn Hamiltonian, and the exciton states are obtained from an exact diagonalization. We found that the presence of the inner layer covering the ring opening enhances the excitonic Aharonov-Bohm (AB) oscillations. The reason is that the hole becomes mainly localized in the inner part of the quantum dot due to strain, whereas the electron resides mainly inside the ring-shaped rim. Interestingly, larger AB oscillations are found in the analyzed quantum dot than in a fully opened quantum ring of the same width. Comparison with the unstrained ringlike quantum dot shows that the amplitude of the excitonic Aharonov-Bohm oscillations are almost doubled in the presence of strain. The computed oscillations of the exciton energy levels are comparable in magnitude to the oscillations measured in recent experiments. DOI: 10.1103/PhysRevB.87.085314 | ||||
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Language | Wos | 000315278000003 | Publication Date | 2013-02-25 | |
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ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 18 | Open Access | |
Notes | ; This work was supported by the EU NoE: SANDiE, the Ministry of Education, Science, and Technological Development of Serbia, and the Flemish Science Foundation (FWO-Vl). ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:107656 | Serial | 3165 | ||
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Author | Neek-Amal, M.; Beheshtian, J.; Shayeganfar, F.; Singh, S.K.; Los, J.H.; Peeters, F.M. | ||||
Title | Spiral graphone and one-sided fluorographene nanoribbons | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 7 | Pages | 075448-8 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The instability of a free-standing one-sided hydrogenated/fluorinated graphene nanoribbon, i.e., graphone/fluorographene, is studied using ab initio, semiempirical, and large-scale molecular dynamics simulations. Free-standing semi-infinite armchairlike hydrogenated/fluorinated graphene (AC-GH/AC-GF) and boatlike hydrogenated/fluorinated graphene (B-GH/B-GF) (nanoribbons which are periodic along the zigzag direction) are unstable and spontaneously transform into spiral structures. We find that rolled, spiral B-GH and B-GF are energetically more favorable than spiral AC-GH and AC-GF which is opposite to the double-sided flat hydrogenated/fluorinated graphene, i.e., graphane/fluorographene. We found that the packed, spiral structures exhibit an unexpected localized highest occupied molecular orbital and lowest occupied molecular orbital at the edges with increasing energy gap during rolling. These rolled hydrocarbon structures are stable beyond room temperature up to at least T = 1000 K within our simulation time of 1 ns. DOI: 10.1103/PhysRevB.87.075448 | ||||
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Language | Wos | 000315481800005 | Publication Date | 2013-02-27 | |
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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 | 14 | Open Access | |
Notes | ; We thank A. Sadeghi, M. R. Ejtehadi, and J. Amini for their useful comments. This work is supported by the ESF EuroGRAPHENE project CONGRAN and the Flemish Science Foundation (FWO-Vl). M.N.-A. is supported by a EU-Marie Curie IIF fellowship program Grant No. 299855. ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:107654 | Serial | 3106 | ||
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Author | Zhang, S.H.; Xu, W.; Badalyan, S.M.; Peeters, F.M. | ||||
Title | Piezoelectric surface acoustical phonon limited mobility of electrons in graphene on a GaAs substrate | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 7 | Pages | 075443-75445 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We study the mobility of Dirac fermions in monolayer graphene on a GaAs substrate, limited by the combined action of the extrinsic potential of piezoelectric surface acoustical phonons of GaAs (PA) and of the intrinsic deformation potential of acoustical phonons in graphene (DA). In the high-temperature (T) regime, the momentum relaxation rate exhibits the same linear dependence on T but different dependencies on the carrier density n, corresponding to the mobility mu proportional to 1 root n and 1/n, respectively for the PA and DA scattering mechanisms. In the low-T Bloch-Gruneisen regime, the mobility shows the same square-root density dependence mu proportional to root n, but different temperature dependencies mu proportional to T-3 and T-4, respectively for PA and DA phonon scattering. DOI: 10.1103/PhysRevB.87.075443 | ||||
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Language | Wos | 000315375200008 | Publication Date | 2013-02-27 | |
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ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 25 | Open Access | |
Notes | ; This work was supported by the ESF-Eurocores program EuroGRAPHENE (CONGRAN project) and the Flemish Science Foundation (FWO-VI). ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:107655 | Serial | 2622 | ||
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Author | Li, B.; Djotyan, A.P.; Hao, Y.L.; Avetisyan, A.A.; Peeters, F.M. | ||||
Title | Effect of a perpendicular magnetic field on the shallow donor states near a semiconductor-metal interface | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 7 | Pages | 075313-75319 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We investigate the influence of an external perpendicular magnetic field on the lowest-energy states of an electron bound to a donor which is located near a semiconductor-metal interface. The problem is treated within the effective mass approach and the lowest-energy states are obtained through (1) the “numerically exact” finite element method, and (2) a variational approach using a trial wave function where all image charges that emerge due to the presence of the metallic gate are taken into account. The trial wave functions are constructed such that they reduce to an exponential behavior for sufficiently small magnetic fields and become Gaussian for intermediate and large magnetic fields. The average electron-donor distance can be controlled by the external magnetic field. We find that the size of the 2p(z) state depends strongly on the magnetic field when the donor is close to the interface, showing a nonmonotonic behavior, in contrast with the ground and the other excited states. DOI: 10.1103/PhysRevB.87.075313 | ||||
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Language | Wos | 000314874800017 | Publication Date | 2013-02-13 | |
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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 | 1 | Open Access | |
Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vl). ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:107664 | Serial | 793 | ||
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Author | Saniz, R.; Partoens, B.; Peeters, F.M. | ||||
Title | Confinement effects on electron and phonon degrees of freedom in nanofilm superconductors : a Green function approach | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 6 | Pages | 064510-64513 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The Green function approach to the Bardeen-Cooper-Schrieffer theory of superconductivity is used to study nanofilms. We go beyond previous models and include effects of confinement on the strength of the electron-phonon coupling as well as on the electronic spectrum and on the phonon modes. Within our approach, we find that in ultrathin films, confinement effects on the electronic screening become very important. Indeed, contrary to what has been advanced in recent years, the sudden increases of the density of states when new bands start to be occupied as the film thickness increases, tend to suppress the critical temperature rather than to enhance it. On the other hand, the increase of the number of phonon modes with increasing number of monolayers in the film leads to an increase in the critical temperature. As a consequence, the superconducting critical parameters in such nanofilms are determined by these two competing effects. Furthermore, in sufficiently thin films, the condensate consists of well-defined subcondensates associated with the occupied bands, each with a distinct coherence length. The subcondensates can interfere constructively or destructively giving rise to an interference pattern in the Cooper pair probability density. | ||||
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Language | Wos | 000315374100009 | Publication Date | 2013-02-25 | |
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ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 6 | Open Access | |
Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vl). R.S. thanks M. R. Norman, B. Soree, and L. Komendova for useful comments. ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:107072 | Serial | 487 | ||
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Author | Van Aert, S.; de Backer, A.; Martinez, G.T.; Goris, B.; Bals, S.; Van Tendeloo, G.; Rosenauer, A. | ||||
Title | Procedure to count atoms with trustworthy single-atom sensitivity | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 6 | Pages | 064107-6 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We report a method to reliably count the number of atoms from high-angle annular dark field scanning transmission electron microscopy images. A model-based analysis of the experimental images is used to measure scattering cross sections at the atomic level. The high sensitivity of these measurements in combination with a thorough statistical analysis enables us to count atoms with single-atom sensitivity. The validity of the results is confirmed by means of detailed image simulations. We will show that the method can be applied to nanocrystals of arbitrary shape, size, and atom type without the need for a priori knowledge about the atomic structure. | ||||
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Language | Wos | 000315144700006 | Publication Date | 2013-02-20 | |
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ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 106 | Open Access | |
Notes | FWO; 262348 ESMI; 312483 ESTEEM2;246791 COUNTATOMS; Hercules 3; esteem2_jra2 | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:105674 | Serial | 2718 | ||
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Author | Zarenia, M.; Pereira, J.M., Jr.; Peeters, F.M.; Farias, G.A. | ||||
Title | Snake states in graphene quantum dots in the presence of a p-n junction | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 3 | Pages | 035426 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We investigate the magnetic interface states of graphene quantum dots that contain p-n junctions. Within a tight-binding approach, we consider rectangular quantum dots in the presence of a perpendicular magnetic field containing p-n as well as p-n-p and n-p-n junctions. The results show the interplay between the edge states associated with the zigzag terminations of the sample and the snake states that arise at the p-n junction due to the overlap between electron and hole states at the potential interface. Remarkable localized states are found at the crossing of the p-n junction with the zigzag edge having a dumb-bell-shaped electron distribution. The results are presented as a function of the junction parameters and the applied magnetic flux. DOI: 10.1103/PhysRevB.87.035426 | ||||
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Language | Wos | 000313941000003 | Publication Date | 2013-01-29 | |
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ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 16 | Open Access | |
Notes | ; This work was supported by the Flemish Science Foundation (FWO-VI), the European Science Foundation (ESF) under the EUROCORES program EuroGRAPHENE (project CONGRAN), the Brazilian agency CNPq (Pronex), and the bilateral projects between Flanders and Brazil and the collaboration project FWO-CNPq. ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:110087 | Serial | 3048 | ||
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Author | Turner, S.; Lebedev, O.I.; Verbeeck, J.; Gehrke, K.; Moshnyaga, V.; Van Tendeloo, G. | ||||
Title | Structural phase transition and spontaneous interface reconstruction in La2/3Ca1/3MnO3/BaTiO3 superlattices | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 3 | Pages | 035418-8 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | (La2/3Ca1/3MnO3)n/(BaTiO3)m (LCMOn/BTOm) superlattices on MgO and SrTiO3 substrates with different layer thicknesses (n = 10, 38, 40 and m = 5, 18, 20) have been grown by metal organic aerosol deposition (MAD) and have been fully characterized down to the atomic scale to study the interface characteristics. Scanning transmission electron microscopy combined with spatially resolved electron energy-loss spectroscopy provides clear evidence for the existence of atomically sharp interfaces in MAD grown films, which exhibit epitaxial growth conditions, a uniform normal strain, and a fully oxidized state. Below a critical layer thickness the LCMO structure is found to change from the bulk Pnma symmetry to a pseudocubic R3̅ c symmetry. An atomically flat interface reconstruction consisting of a single Ca-rich atomic layer is observed on the compressively strained BTO on LCMO interface, which is thought to partially neutralize the total charge from the alternating polar atomic layers in LCMO as well as relieving strain at the interface. No interface reconstruction is observed at the tensile strained LCMO on BTO interface. | ||||
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Language | Wos | 000313940400008 | Publication Date | 2013-01-23 | |
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ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 12 | Open Access | |
Notes | FWO; Hercules; Countatoms | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:106180 | Serial | 3245 | ||
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Author | Esfahani, D.N.; Covaci, L.; Peeters, F.M. | ||||
Title | Field effect on surface states in a doped Mott-insulator thin film | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 3 | Pages | 035131-35136 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Surface effects of a doped thin film made of a strongly correlated material are investigated both in the absence and presence of a perpendicular electric field. We use an inhomogeneous Gutzwiller approximation for a single-band Hubbard model in order to describe correlation effects. For low doping, the bulk value of the quasiparticle weight is recovered exponentially deep into the slab, but with increasing doping, additional Friedel oscillations appear near the surface. We show that the inverse correlation length has a power-law dependence on the doping level. In the presence of an electrical field, considerable changes in the quasiparticle weight can be realized throughout the system. We observe a large difference (as large as five orders of magnitude) in the quasiparticle weight near the opposite sides of the slab. This effect can be significant in switching devices that use the surface states for transport. DOI: 10.1103/PhysRevB.87.035131 | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000313941000001 | Publication Date | 2013-01-29 | |
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 | 4 | Open Access | |
Notes | ; This work was supported by the Flemish Science Foundation (FWO-VI). ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:110086 | Serial | 1190 | ||
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Author | Geurts, R.; Milošević, M.V.; Albino Aguiar, J.; Peeters, F.M. | ||||
Title | Enhanced stability of vortex-antivortex states in two-component mesoscopic superconductors | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 2 | Pages | 024501-24508 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Using the Ginzburg-Landau (GL) theory, we calculate the stability of sample symmetry-induced vortex-antivortex molecules in a mesoscopic superconducting bilayer exposed to a homogeneous magnetic field. We demonstrate the conditions under which the two condensates cooperatively broaden the field-temperature stability range of the composite (joint) vortex-antivortex state. In cases when such broadening is not achieved, a reentrance of the vortex-antivortex state is found at lower temperatures. In a large portion of the phase diagram noncomposite states are possible, in which the antivortex is present in only one of the layers. In this case, we demonstrate that the vortex-antivortex molecule in one of the layers can be pinned and enlarged by interaction with a vortex molecule in the other. Using analogies in the respective GL formalisms, we map our findings for the bilayer onto mesoscopic two-band superconductors. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000313029800003 | Publication Date | 2013-01-04 | |
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 | 25 | Open Access | |
Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen), the Brazilian science agencies FACEPE/CNPq under Grant No. APQ-0589-1.05/08 and CNPq under Grant No. 309832/2007-1, and the CNPq-FWO cooperation program under Grant No. 490681/2010-7. M.V.M. acknowledges support from the CAPES-PVE program. ; | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | ||
Call Number | UA @ lucian @ c:irua:105925 | Serial | 1058 | ||
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Author | Abakumov, A.M.; Batuk, D.; Tsirlin, A.A.; Prescher, C.; Dubrovinsky, L.; Sheptyakov, D.V.; Schnelle, W.; Hadermann, J.; Van Tendeloo, G. | ||||
Title | Frustrated pentagonal Cairo lattice in the non-collinear antiferromagnet Bi4Fe5O13F | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
Volume | 87 | Issue | 2 | Pages | 024423-24429 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We report on the crystal structure and magnetism of the iron-based oxyfluoride Bi4Fe5O13F, a material prototype of the Cairo pentagonal spin lattice. The crystal structure of Bi4Fe5O13F is determined by a combination of neutron diffraction, synchrotron x-ray diffraction, and transmission electron microscopy. It comprises layers of FeO6 octahedra and FeO4 tetrahedra forming deformed pentagonal units. The topology of these layers resembles a pentagonal least-perimeter tiling, which is known as the Cairo lattice. This topology gives rise to frustrated exchange couplings and underlies a sequence of magnetic transitions at T-1 = 62 K, T-2 = 71 K, and T-N = 178 K, as determined by thermodynamic measurements and neutron diffraction. Below T-1, Bi4Fe5O13F forms a fully ordered non-collinear antiferromagnetic structure, whereas the magnetic state between T-1 and T-N may be partially disordered according to the sizable increase in the magnetic entropy at T-1 and T-2. Bi4Fe5O13F reveals unanticipated magnetic transitions on the pentagonal Cairo spin lattice and calls for a further work on finite-temperature properties of this strongly frustrated spin model. DOI: 10.1103/PhysRevB.87.024423 | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000314224800002 | Publication Date | 2013-02-01 | |
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 | 17 | Open Access | |
Notes | Approved | Most recent IF: 3.836; 2013 IF: 3.664 | |||
Call Number | UA @ lucian @ c:irua:107688 | Serial | 1293 | ||
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Author | Lubk, A.; Clark, L.; Guzzinati, G.; Verbeeck, J. | ||||
Title | Topological analysis of paraxially scattered electron vortex beams | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review : A : atomic, molecular and optical physics | Abbreviated Journal | Phys Rev A |
Volume | 87 | Issue | 3 | Pages | 033834-33838 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We investigate topological aspects of subnanometer electron vortex beams upon elastic propagation through atomic scattering potentials. Two main aspects can be distinguished: (i) significantly reduced delocalization compared to a similar nonvortex beam if the beam centers on an atomic column and (ii) site symmetry dependent splitting of higher-order vortex beams. Furthermore, the results provide insight into the complex vortex line fabric within the elastically scattered wave containing characteristic vortex loops predominantly attached to atomic columns and characteristic twists of vortex lines around atomic columns. DOI: 10.1103/PhysRevA.87.033834 | ||||
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Corporate Author | Thesis | ||||
Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
Language | Wos | 000316790600011 | Publication Date | 2013-03-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1050-2947;1094-1622; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.925 | Times cited | 26 | Open Access | |
Notes | Countatoms; Vortex; Esteem2; esteem2jra3 ECASJO; | Approved | Most recent IF: 2.925; 2013 IF: 2.991 | ||
Call Number | UA @ lucian @ c:irua:108496 | Serial | 3673 | ||
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Author | Schryvers, D.; Cao, S.; Tirry, W.; Idrissi, H.; Van Aert, S. | ||||
Title | Advanced three-dimensional electron microscopy techniques in the quest for better structural and functional materials | Type | A1 Journal article | ||
Year | 2013 | Publication | Science and technology of advanced materials | Abbreviated Journal | Sci Technol Adv Mat |
Volume | 14 | Issue | 1 | Pages | 014206-14213 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | After a short review of electron tomography techniques for materials science, this overview will cover some recent results on different shape memory and nanostructured metallic systems obtained by various three-dimensional (3D) electron imaging techniques. In binary NiTi, the 3D morphology and distribution of Ni4Ti3 precipitates are investigated by using FIB/SEM slice-and-view yielding 3D data stacks. Different quantification techniques will be presented including the principal ellipsoid for a given precipitate, shape classification following a Zingg scheme, particle distribution function, distance transform and water penetration. The latter is a novel approach to quantifying the expected matrix transformation in between the precipitates. The different samples investigated include a single crystal annealed with and without compression yielding layered and autocatalytic precipitation, respectively, and a polycrystal revealing different densities and sizes of the precipitates resulting in a multistage transformation process. Electron tomography was used to understand the interaction between focused ion beam-induced Frank loops and long dislocation structures in nanobeams of Al exhibiting special mechanical behaviour measured by on-chip deposition. Atomic resolution electron tomography is demonstrated on Ag nanoparticles in an Al matrix. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Sendai | Editor | ||
Language | Wos | 000316463800008 | Publication Date | 2013-03-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1468-6996;1878-5514; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.798 | Times cited | 6 | Open Access | |
Notes | Fwo; Iap; Esteem | Approved | Most recent IF: 3.798; 2013 IF: 2.613 | ||
Call Number | UA @ lucian @ c:irua:107343 | Serial | 77 | ||
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Author | Villegas, C.E.P.; Tavares, M.R.S.; Hai, G.-Q.; Peeters, F.M. | ||||
Title | Sorting the modes contributing to guidance in strain-induced graphene waveguides | Type | A1 Journal article | ||
Year | 2013 | Publication | New journal of physics | Abbreviated Journal | New J Phys |
Volume | 15 | Issue | Pages | 023015-11 | |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We propose a simple way of probing the number of modes contributing to the channeling in graphene waveguides which are formed by a gauge potential produced by mechanical strain. The energy mode structure for both homogeneous and non-homogeneous strain regimes is carefully studied using the continuum description of the Dirac equation. We found that high strain values privilege negative (instead of positive) group velocities throughout the guidance, sorting the types of modes flowing through it. We also show how the effect of a substrate-induced gap competes against the strain. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Bristol | Editor | ||
Language | Wos | 000314868000002 | Publication Date | 2013-02-08 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1367-2630; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.786 | Times cited | 7 | Open Access | |
Notes | ; This work was supported by FAPESP, CNPq and the Flemish Science Foundation (FWO-VI). ; | Approved | Most recent IF: 3.786; 2013 IF: 3.671 | ||
Call Number | UA @ lucian @ c:irua:107667 | Serial | 3056 | ||
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Author | Park, K.; De Beule, C.; Partoens, B. | ||||
Title | The ageing effect in topological insulators : evolution of the surface electronic structure of Bi2Se3 upon K adsorption | Type | A1 Journal article | ||
Year | 2013 | Publication | New journal of physics | Abbreviated Journal | New J Phys |
Volume | 15 | Issue | Pages | 113031-16 | |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Topological insulators (TIs) have attracted a lot of interest in recent years due to their topologically protected surface states, as well as exotic proximity-induced phenomena and device applications for TI heterostructures. Since the first experimental studies of TIs, angle-resolved photoemission spectra (ARPES) showed that the electronic structure of the topological surface states significantly changes as a function of time after cleavage. The origin and underlying mechanism of this ageing effect are still under debate, despite its importance. Here we investigate the evolution of the surface Dirac cone for Bi2Se3 films upon asymmetric potassium (K) adsorption, using density-functional theory and a tight-binding model. We find that the K adatoms induce short-ranged downward band bending within 2-3 nm from the surface, due to charge transfer from the adatoms to the TI. These findings are in contrast to earlier proposals in the literature, that propose a long-ranged downward band bending up to 15 nm from the surface. Furthermore, as the charge transfer increases, we find that a new Dirac cone, localized slightly deeper into the TI than the original one, appears at the K-adsorbed surface, originating from strong Rashba-split conduction-band states. Our results suggest possible reinterpretations of experiments because the new Dirac cone might have been observed in ARPES measurements instead of the original one that appears immediately after cleavage. Our findings are consistent with ARPES data and provide insight into building TI-heterostructure devices by varying the band-bending potential or film thickness. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Bristol | Editor | ||
Language | Wos | 000326876100006 | Publication Date | 2013-11-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1367-2630; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.786 | Times cited | 45 | Open Access | |
Notes | ; KP was supported by National Science Foundation grant numbers DMR-0804665 and DMR-1206354 and SDSC Trestles under DMR060009N. CDB was supported by the Research Foundation Flanders (FWO). ; | Approved | Most recent IF: 3.786; 2013 IF: 3.671 | ||
Call Number | UA @ lucian @ c:irua:112707 | Serial | 84 | ||
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Author | Kapra, A.V.; Vodolazov, D.Y.; Misko, V.R. | ||||
Title | Vortex transport in a channel with periodic constrictions | Type | A1 Journal article | ||
Year | 2013 | Publication | Superconductor science and technology | Abbreviated Journal | Supercond Sci Tech |
Volume | 26 | Issue | 9 | Pages | 095010-95011 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | By numerically solving the time-dependent Ginzburg-Landau equations in a type-II superconductor, characterized by a critical temperature T-c1, and the coherence length xi(1), with a channel formed by overlapping rhombuses (diamond-like channel) made of another type-II superconductor, characterized, in general, by different T-c2 and xi(2), we investigate the dynamics of driven vortex matter for varying parameters of the channel: the width of the neck connecting the diamond cells, the cell geometry, and the ratio between the coherence lengths in the bank and the channel. We analyzed samples with periodic boundary conditions (which we call 'infinite' samples) and finite-size samples (with boundaries for vortex entry/exit), and we found that by tuning the channel parameters, one can manipulate the vortex dynamics, e.g., change the transition from flux-pinned to flux-flow regime and tune the slope of the IV-curves. In addition, we analyzed the effect of interstitial vortices on these characteristics. The critical current of this device was studied as a function of the applied magnetic field, j(c)(H). The function j(c)(H) reveals a striking commensurability peak, in agreement with recent experimental observations. The obtained results suggest that the diamond channel, which combines the properties of pinning arrays and flux-guiding channels, can be a promising candidate for potential use in devices controlling magnetic flux motion. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Bristol | Editor | ||
Language | Wos | 000323073800016 | Publication Date | 2013-07-30 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0953-2048;1361-6668; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.878 | Times cited | 2 | Open Access | |
Notes | ; This work was supported by the 'Odysseus' Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl). ; | Approved | Most recent IF: 2.878; 2013 IF: 2.796 | ||
Call Number | UA @ lucian @ c:irua:110737 | Serial | 3898 | ||
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Author | Zarenia, M.; Vasilopoulos, P.; Pourtolami, N.; Peeters, F.M. | ||||
Title | Landau-level dispersion and the quantum Hall plateaus in bilayer graphene | Type | P1 Proceeding | ||
Year | 2013 | Publication | AIP conference proceedings | Abbreviated Journal | |
Volume | 1566 | Issue | Pages | 275-276 | |
Keywords | P1 Proceeding; Condensed Matter Theory (CMT) | ||||
Abstract | We study the quantum Hall effect (QHE) in bilayer graphene using the Kubo-Greenwood formula. At zero temperature the Hall conductivity sigma(yx) is given by sigma(yx) – 4(N + 1)e(2)/h with N the index of the highest occupied Landau level (LL). Including the dispersion of the LLs and their width, due to e. g. scattering by impurities, produces the plateau of the n = 0 LL in agreement with experimental results on doped samples and similar theoretical results on single-layer graphene plateaus widen with impurity concentration. Further, the evaluated resistivity rho(xx) exhibits a strong, oscillatory dependence on the electron concentration. Explicit results are obtained for delta-function impurities. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York | Editor | ||
Language | Wos | 000331793000137 | Publication Date | 2014-01-03 | |
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 | ; This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (project CONGRAN) and the Canadian NSERC Grant No. OGP0121756. ; | Approved | Most recent IF: NA | ||
Call Number | UA @ lucian @ c:irua:115871 | Serial | 1770 | ||
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Author | Egoavil, R.; Tan, H.; Verbeeck, J.; Bals, S.; Smith, B.; Kuiper, B.; Rijnders, G.; Koster, G.; Van Tendeloo, G. | ||||
Title | Atomic scale investigation of a PbTiO3/SrRuO3/DyScO3 heterostructure | Type | A1 Journal article | ||
Year | 2013 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume | 102 | Issue | 22 | Pages | 223106-5 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | An epitaxial PbTiO3 thin film grown on self-organized crystalline SrRuO3 nanowires deposited on a DyScO3 substrate with ordered DyO and ScO2 chemical terminations is investigated by transmission electron microscopy. In this PbTiO3/SrRuO3/DyScO3 heterostructure, the SrRuO3 nanowires are assumed to grow on only one type of substrate termination. Here, we report on the structure, morphology, and chemical composition analysis of this heterostructure. Electron energy loss spectroscopy reveals the exact termination sequence in this complex structure. The energy loss near-edge structure of the Ti-L-2,L-3, Sc-L-2,L-3, and O K edges shows intrinsic interfacial electronic reconstruction. Furthermore, PbTiO3 domain walls are observed to start at the end of the nanowires resulting in atomic steps on the film surface. (C) 2013 AIP Publishing LLC. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000320621600070 | Publication Date | 2013-06-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 12 | Open Access | |
Notes | Ifox; Esteem2; Countatoms; Vortex; esteem2jra3 ECASJO; | Approved | Most recent IF: 3.411; 2013 IF: 3.515 | ||
Call Number | UA @ lucian @ c:irua:109606UA @ admin @ c:irua:109606 | Serial | 185 | ||
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Author | Lindell, L.; Çakir, D.; Brocks, G.; Fahlman, M.; Braun, S. | ||||
Title | Role of intrinsic molecular dipole in energy level alignment at organic interfaces | Type | A1 Journal article | ||
Year | 2013 | Publication | Applied Physics Letters | Abbreviated Journal | Appl Phys Lett |
Volume | 102 | Issue | 22 | Pages | 223301 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The energy level alignment in metal-organic and organic-organic junctions of the widely used materials tris-(8-hydroxyquinoline) aluminum (Alq(3)) and 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTCDA) is investigated. The measured alignment schemes for single and bilayer films of Alq(3) and NTCDA are interpreted with the integer charge transfer (ICT) model. Single layer films of Alq(3) feature a constant vacuum level shift of similar to 0.2-0.4 eV in the absence of charge transfer across the interface. This finding is attributed to the intrinsic dipole of the Alq(3) molecule and (partial) ordering of the molecules at the interfaces. The vacuum level shift changes the onset of Fermi level pinning, as it changes the energy needed for equilibrium charge transfer across the interface. (C) 2013 AIP Publishing LLC. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000320621600081 | Publication Date | 2013-06-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951; 1077-3118 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 22 | Open Access | |
Notes | ; We acknowledge funding from the European Community's Framework Programme under Grant No. FP7-NMP-228424 of the MINOTOR project as well as a project grant from the Swedish Energy Agency, STEM. ; | Approved | Most recent IF: 3.411; 2013 IF: 3.515 | ||
Call Number | UA @ lucian @ c:irua:128323 | Serial | 4605 | ||
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Author | Schouteden, K.; Zeng, Y.-J.; Lauwaet, K.; Romero, C.P.; Goris, B.; Bals, S.; Van Tendeloo, G.; Lievens, P.; Van Haesendonck, C. | ||||
Title | Band structure quantization in nanometer sized ZnO clusters | Type | A1 Journal article | ||
Year | 2013 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 5 | Issue | 9 | Pages | 3757-3763 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Nanometer sized ZnO clusters are produced in the gas phase and subsequently deposited on clean Au(111) surfaces under ultra-high vacuum conditions. The zinc blende atomic structure of the approximately spherical ZnO clusters is resolved by high resolution scanning transmission electron microscopy. The large band gap and weak n-type conductivity of individual clusters are determined by scanning tunnelling microscopy and spectroscopy at cryogenic temperatures. The conduction band is found to exhibit clear quantization into discrete energy levels, which can be related to finite-size effects reflecting the zero-dimensional confinement. Our findings illustrate that gas phase cluster production may provide unique possibilities for the controlled fabrication of high purity quantum dots and heterostructures that can be size selected prior to deposition on the desired substrate under controlled ultra-high vacuum conditions. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000317859400026 | Publication Date | 2013-03-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364;2040-3372; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.367 | Times cited | 13 | Open Access | |
Notes | FWO; Hercules; COUNTATOMS | Approved | Most recent IF: 7.367; 2013 IF: 6.739 | ||
Call Number | UA @ lucian @ c:irua:108518 | Serial | 219 | ||
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Author | Mourdikoudis, S.; Chirea, M.; Altantzis, T.; Pastoriza-Santos, I.; Perez-Juste, J.; Silva, F.; Bals, S.; Liz-Marzan, L.M. | ||||
Title | Dimethylformamide-mediated synthesis of water-soluble platinum nanodendrites for ethanol oxidation electrocatalysis | Type | A1 Journal article | ||
Year | 2013 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
Volume | 5 | Issue | 11 | Pages | 4776-4784 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Herein we describe the synthesis of water-soluble platinum nanodendrites in dimethylformamide (DMF), in the presence of polyethyleneimine (PEI) as a stabilizing agent. The average size of the dendrites is in the range of 20-25 nm while their porosity can be tuned by modifying the concentration of the metal precursor. Electron tomography revealed different crystalline orientations of nanocrystallites in the nanodendrites and allowed a better understanding of their peculiar branching and porosity. The high surface area of the dendrites (up to 22 m(2) g(-1)) was confirmed by BET measurements, while X-ray diffraction confirmed the abundance of high-index facets in the face-centered-cubic crystal structure of Pt. The prepared nanodendrites exhibit excellent performance in the electrocatalytic oxidation of ethanol in alkaline solution. Sensing, selectivity, cycleability and great tolerance toward poisoning were demonstrated by cyclic voltammetry measurements. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000319008700028 | Publication Date | 2013-04-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2040-3364;2040-3372; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 7.367 | Times cited | 50 | Open Access | |
Notes | Esf; 262348 Esmi | Approved | Most recent IF: 7.367; 2013 IF: 6.739 | ||
Call Number | UA @ lucian @ c:irua:109060 | Serial | 705 | ||
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Author | Schoeters, B.; Neyts, E.C.; Khalilov, U.; Pourtois, G.; Partoens, B. | ||||
Title | Stability of Si epoxide defects in Si nanowires : a mixed reactive force field/DFT study | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
Volume | 15 | Issue | 36 | Pages | 15091-15097 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
Abstract | Modeling the oxidation process of silicon nanowires through reactive force field based molecular dynamics simulations suggests that the formation of Si epoxide defects occurs both at the Si/SiOx interface and at the nanowire surface, whereas for flat surfaces, this defect is experimentally observed to occur only at the interface as a result of stress. In this paper, we argue that the increasing curvature stabilizes the defect at the nanowire surface, as suggested by our density functional theory calculations. The latter can have important consequences for the opto-electronic properties of thin silicon nanowires, since the epoxide induces an electronic state within the band gap. Removing the epoxide defect by hydrogenation is expected to be possible but becomes increasingly difficult with a reduction of the diameter of the nanowires. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Cambridge | Editor | ||
Language | Wos | 000323520600029 | Publication Date | 2013-07-16 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1463-9076;1463-9084; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4.123 | Times cited | 3 | Open Access | |
Notes | ; BS gratefully acknowledges financial support of the IWT, Institute for the Promotion of Innovation by Science and Technology in Flanders, via the SBO project “SilaSol”. This work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish government and the Universiteit Antwerpen. ; | Approved | Most recent IF: 4.123; 2013 IF: 4.198 | ||
Call Number | UA @ lucian @ c:irua:110793 | Serial | 3130 | ||
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Author | Shuhui Sun, Gaixia Zhang, Nicolas Gauquelin, Ning Chen, Jigang Zhou, Songlan Yang, Weifeng Chen, Xiangbo Meng, Dongsheng Geng, Mohammad N. Banis, Ruying Li, Siyu Ye, Shanna Knights, Gianluigi A. Botton, Tsun-Kong Sham & Xueliang Sun | ||||
Title | Single-atom Catalysis Using Pt/Graphene Achieved through Atomic Layer Deposition | Type | A1 Journal Article | ||
Year | 2013 | Publication | Scientific Reports | Abbreviated Journal | |
Volume | 3 | Issue | Pages | 1775 | |
Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
Abstract | Platinum-nanoparticle-based catalysts are widely used in many important chemical processes and automobile industries. Downsizing catalyst nanoparticles to single atoms is highly desirable to maximize their use efficiency, however, very challenging. Here we report a practical synthesis for isolated single Pt atoms anchored to graphene nanosheet using the atomic layer deposition (ALD) technique. ALD offers the capability of precise control of catalyst size span from single atom, subnanometer cluster to nanoparticle. The single-atom catalysts exhibit significantly improved catalytic activity (up to 10 times) over that of the state-of-the-art commercial Pt/C catalyst. X-ray absorption fine structure (XAFS) analyses reveal that the low-coordination and partially unoccupied densities of states of 5d orbital of Pt atoms are responsible for the excellent performance. This work is anticipated to form the basis for the exploration of a next generation of highly efficient single-atom catalysts for various applications. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000318334300004 | Publication Date | 2013-05-03 | |
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ISSN | ISBN | Additional Links | |||
Impact Factor | Times cited | 345 | Open Access | ||
Notes | Approved | Most recent IF: NA | |||
Call Number | EMAT @ emat @ | Serial | 4543 | ||
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Author | Evers, W.H.; Goris, B.; Bals, S.; Casavola, M.; de Graaf, J.; van Roij, R.; Dijkstra, M.; Vanmaekelbergh, D. | ||||
Title | Low-dimensional semiconductor superlattices formed by geometric control over nanocrystal attachment | Type | A1 Journal article | ||
Year | 2013 | Publication | Nano letters | Abbreviated Journal | Nano Lett |
Volume | 13 | Issue | 6 | Pages | 2317-2323 |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Oriented attachment, the process in which nanometer-sized crystals fuse by atomic bonding of specific crystal facets, is expected to be more difficult to control than nanocrystal self-assembly that is driven by entropic factors or weak van der Waals attractions. Here, we present a study of oriented attachment of PbSe nanocrystals that counteract this tuition. The reaction was studied in a thin film of the suspension casted on an immiscible liquid at a given temperature. We report that attachment can be controlled such that it occurs with one type of facets exclusively. By control of the temperature and particle concentration we obtain one- or two-dimensional PbSe single crystals, the latter with a honeycomb or square superimposed periodicity in the nanometer range. We demonstrate the ability to convert these PbSe superstructures into other semiconductor compounds with the preservation of crystallinity and geometry. | ||||
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Publisher | Place of Publication | Washington | Editor | ||
Language | Wos | 000320485100001 | Publication Date | 2012-10-11 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 1530-6984;1530-6992; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 12.712 | Times cited | 206 | Open Access | |
Notes | 262348 ESMI; Hercules 3 | Approved | Most recent IF: 12.712; 2013 IF: 12.940 | ||
Call Number | UA @ lucian @ c:irua:101777 | Serial | 1847 | ||
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Author | Dunin-Borkowski, R.E.; Lichte, H.; Tillmann, K.; Van Aert, S.; Van Tendeloo, G. | ||||
Title | Introduction to a special issue in honour of W. Owen Saxton, David J. Smith and Dirk Van Dyck on the occasion of their 65th birthdays | Type | Editorial | ||
Year | 2013 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume | 134 | Issue | Pages | 1-1 | |
Keywords | Editorial; Electron microscopy for materials research (EMAT) | ||||
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Publisher | Elsevier science bv | Place of Publication | Amsterdam | Editor | |
Language | Wos | 000324474900001 | Publication Date | 2013-07-24 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 1 | Open Access | |
Notes | Approved | Most recent IF: 2.843; 2013 IF: 2.745 | |||
Call Number | UA @ lucian @ c:irua:109917 | Serial | 1721 | ||
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