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| Author | Domingos, J.L.C.; Peeters, F.M.; Ferreira, W.P. | ||||
| Title | Self-assembly of rigid magnetic rods consisting of single dipolar beads in two dimensions | Type | A1 Journal article | ||
Year  |
2017 | Publication | Physical review E | Abbreviated Journal | Phys Rev E |
| Volume | 96 | Issue | 1 | Pages | 012603 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Molecular dynamics simulations are used to investigate the structural properties of a two-dimensional ensemble of magnetic rods, which are modeled as aligned single dipolar beads. The obtained self-assembled configurations can be characterized as (1) clusters, (2) percolated, and (3) ordered structures, and their structural properties are investigated in detail. By increasing the aspect ratio of the magnetic rods, we show that the percolation transition is suppressed due to the reduced mobility of the rods in two dimensions. Such a behavior is opposite to the one observed in three dimensions. A magnetic bulk phase is found with local ferromagnetic order and an unusual nonmonotonic behavior of the nematic order is observed. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000405713900014 | Publication Date | 2017-07-18 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2470-0045;2470-0053; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.366 | Times cited | 8 | Open Access | |
| Notes | ; This work was supported by the Brazilian agencies FUNCAP, CAPES, program Science without borders, and CNPq (Project No. 400748/2013-4), the joint CNPq-FWO bilateral project, and the Flemish Science Foundation (FWO-V1). ; | Approved | Most recent IF: 2.366 | ||
| Call Number | UA @ lucian @ c:irua:145210 | Serial | 4723 | ||
| Permanent link to this record | |||||
| Author | Kong, X.; Li, L.; Leenaerts, O.; Liu, X.-J.; Peeters, F.M. | ||||
| Title | New group-V elemental bilayers : a tunable structure model with four-, six-, and eight-atom rings | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 96 | Issue | 3 | Pages | 035123 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Two-dimensional group-V elemental materials have attracted widespread attention due to their nonzero band gap while displaying high electron mobility. Using first-principles calculations, we propose a series of new elemental bilayers with group-V elements (Bi, Sb, As). Our study reveals the dynamical stability of four-, six-, and eight-atom ring structures, demonstrating their possible coexistence in such bilayer systems. The proposed structures for Sb and As are large-gap semiconductors that are potentially interesting for applications in future nanodevices. The Bi structures have nontrivial topological properties with a direct nontrivial band gap. The nontrivial gap is shown to arise from a band inversion at the Brillouin zone center due to the strong intrinsic spin-orbit coupling in Bi atoms. Moreover, we demonstrate the possibility of tuning the properties of these materials by enhancing the ratio of six-atom rings to four-and eight-atom rings, which results in wider nontrivial band gaps and lower formation energies. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
| Language | Wos | 000405363900005 | Publication Date | 2017-07-14 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 14 | Open Access | |
| Notes | ; This work is supported by Ministry of Science and Technology of China (MOST) (Grant No. 2016YFA0301604), National Natural Science Foundation of China (NSFC) ( No. 11574008), the Thousand-Young-Talent Program of China, and the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government – department EWI, and the National Supercomputing Center in Tianjin, funded by the Collaborative Innovation Center of Quantum Matter. ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ lucian @ c:irua:144834 | Serial | 4721 | ||
| Permanent link to this record | |||||
| Author | Embon, L.; Anahory, Y.; Jelić, Z.L.; Lachman, E.O.; Myasoedov, Y.; Huber, M.E.; Mikitik, G.P.; Silhanek, A.V.; Milošević, M.V.; Gurevich, A.; Zeldov, E. | ||||
| Title | Imaging of super-fast dynamics and flow instabilities of superconducting vortices | Type | A1 Journal article | ||
| Year |
2017 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
| Volume | 8 | Issue | Pages | 85 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
| Abstract | Quantized magnetic vortices driven by electric current determine key electromagnetic properties of superconductors. While the dynamic behavior of slow vortices has been thoroughly investigated, the physics of ultrafast vortices under strong currents remains largely unexplored. Here, we use a nanoscale scanning superconducting quantum interference device to image vortices penetrating into a superconducting Pb film at rates of tens of GHz and moving with velocities of up to tens of km/s, which are not only much larger than the speed of sound but also exceed the pair-breaking speed limit of superconducting condensate. These experiments reveal formation of mesoscopic vortex channels which undergo cascades of bifurcations as the current and magnetic field increase. Our numerical simulations predict metamorphosis of fast Abrikosov vortices into mixed Abrikosov-Josephson vortices at even higher velocities. This work offers an insight into the fundamental physics of dynamic vortex states of superconductors at high current densities, crucial for many applications. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000405900400002 | Publication Date | 2017-07-13 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.124 | Times cited | 124 | Open Access | |
| Notes | ; We would like to thank M.L. Rappaport for fruitful discussions and technical support. This work was supported by the US-Israel Binational Science Foundation (BSF) grant No. 2014155 and the Israel Science Foundation grant No. 132/14. A.G. was also supported by the United States Department of Energy under Grant No. DE-SC0010081. M.V.M. acknowledges support from Research Foundation-Flanders (FWO). The work of Z.L.J. and A.V.S. was partially supported by “Mandat d'Impulsion Scientifique” MIS F.4527.13 of the F.R.S.-FNRS. This work benefited from the support of COST action MP-1201. ; | Approved | Most recent IF: 12.124 | ||
| Call Number | UA @ lucian @ c:irua:144832 | Serial | 4720 | ||
| Permanent link to this record | |||||
| Author | Chirayath, V.A.; Callewaert, V.; Fairchild, A.J.; Chrysler, M.D.; Gladen, R.W.; Mcdonald, A.D.; Imam, S.K.; Shastry, K.; Koymen, A.R.; Saniz, R.; Barbiellini, B.; Rajeshwar, K.; Partoens, B.; Weiss, A.H. | ||||
| Title | Auger electron emission initiated by the creation of valence-band holes in graphene by positron annihilation | Type | A1 Journal article | ||
| Year |
2017 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
| Volume | 8 | Issue | 8 | Pages | 16116 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
| Abstract | Auger processes involving the filling of holes in the valence band are thought to make important contributions to the low-energy photoelectron and secondary electron spectrum from many solids. However, measurements of the energy spectrum and the efficiency with which electrons are emitted in this process remain elusive due to a large unrelated background resulting from primary beam-induced secondary electrons. Here, we report the direct measurement of the energy spectra of electrons emitted from single layer graphene as a result of the decay of deep holes in the valence band. These measurements were made possible by eliminating competing backgrounds by employing low-energy positrons (<1.25 eV) to create valence-band holes by annihilation. Our experimental results, supported by theoretical calculations, indicate that between 80 and 100% of the deep valence-band holes in graphene are filled via an Auger transition. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000405398200001 | Publication Date | 2017-07-13 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.124 | Times cited | 20 | Open Access | |
| Notes | The experiments in this work were supported by the grant NSF DMR 1508719. A.H.W and A.R.K. gratefully acknowledge support for the building of advanced positron beam through the grant NSF DMR MRI 1338130. V.C. and R.S. were supported by the FWO-Vlaanderen through Project No. G. 0224.14N. The computational resources and services used in this work were in part provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the Hercules Foundation and the Flemish Government (EWI Department). The work at Northeastern University was supported by the US Department of Energy (DOE), Office of Science, Basic Energy Sciences grant number DE-FG02-07ER46352 (core research), and benefited from Northeastern University’s Advanced Scientific Computation Center (ASCC), the NERSC supercomputing center through DOE grant number DE-AC02-05CH11231, and support (applications to layered materials) from the DOE EFRC: Center for the Computational Design of Functional Layered Materials (CCDM) under DE-SC0012575. | Approved | Most recent IF: 12.124 | ||
| Call Number | CMT @ cmt @ c:irua:144625 | Serial | 4627 | ||
| Permanent link to this record | |||||
| Author | de Araujo, J.L.B.; Munarin, F.F.; Farias, G.A.; Peeters, F.M.; Ferreira, W.P. | ||||
| Title | Structure and reentrant percolation in an inverse patchy colloidal system | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical Review E | Abbreviated Journal | |
| Volume | 95 | Issue | 6 | Pages | 062606 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Two-dimensional systems of inverse patchy colloids modeled as disks with a central charge and having their surface decorated with oppositely pointlike charged patches are investigated using molecular dynamics simulations. The self-assembly of the patchy colloids leads to diverse ground state configurations ranging from crystalline arrangements of monomers to linear clusters, ramified linear clusters and to percolated configurations. Two structural phase diagrams are constructed: (1) as a function of the net charge and area fraction, and (2) as a function of the net charge and the range of the pair interaction potential. An interesting reentrant percolation transition is obtained as a function of the net charge of the colloids. We identify distinct mechanisms that lead to the percolation transition. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000404545700005 | Publication Date | 2017-06-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | ||
| Impact Factor | Times cited | 5 | Open Access | ||
| Notes | Approved | no | |||
| Call Number | UA @ admin @ c:irua:152628 | Serial | 8587 | ||
| Permanent link to this record | |||||
| Author | Stosic, D.; Mulkers, J.; Van Waeyenberge, B.; Ludermir, T.B.; Milošević, M.V. | ||||
| Title | Paths to collapse for isolated skyrmions in few-monolayer ferromagnetic films | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 95 | Issue | 21 | Pages | 214418 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Magnetic skyrmions are topological spin configurations in materials with chiral Dzyaloshinskii-Moriya interaction (DMI), that are potentially useful for storing or processing information. To date, DMI has been found in few bulk materials, but can also be induced in atomically thin magnetic films in contact with surfaces with large spin-orbit interactions. Recent experiments have reported that isolated magnetic skyrmions can be stabilized even near room temperature in few-atom-thick magnetic layers sandwiched between materials that provide asymmetric spin-orbit coupling. Here we present the minimum-energy path analysis of three distinct mechanisms for the skyrmion collapse, based on ab initio input and the performed atomic-spin simulations. We focus on the stability of a skyrmion in three atomic layers of Co, either epitaxial on the Pt(111) surface or within a hybrid multilayer where DMI nontrivially varies per monolayer due to competition between different symmetry breaking from two sides of the Co film. In laterally finite systems, their constrained geometry causes poor thermal stability of the skyrmion toward collapse at the boundary, which we show to be resolved by designing the high-DMI structure within an extended film with lower or no DMI. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000404015500001 | Publication Date | 2017-06-23 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 48 | Open Access | |
| Notes | This work was supported by the Research Foundation, Flanders (FWO-Vlaanderen) and Brazilian agency CNPq (Grants No. 442668/2014-7 and No. 140840/2016-8). | Approved | Most recent IF: 3.836 | ||
| Call Number | CMT @ cmt @c:irua:144865 | Serial | 4704 | ||
| Permanent link to this record | |||||
| Author | Doevenspeck, J.; Zografos, O.; Gurunarayanan, S.; Lauwereins, R.; Raghavan, P.; Sorée, B. | ||||
| Title | Design and simulation of plasmonic interference-based majority gate | Type | A1 Journal article | ||
| Year |
2017 | Publication | AIP advances | Abbreviated Journal | |
| Volume | 7 | Issue | 6 | Pages | 065116 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
| Abstract | Major obstacles in current CMOS technology, such as the interconnect bottleneck and thermal heat management, can be overcome by employing subwavelength-scaled light in plasmonic waveguides and devices. In this work, a plasmonic structure that implements the majority (MAJ) gate function is designed and thoroughly studied through simulations. The structure consists of three merging waveguides, serving as the MAJ gate inputs. The information of the logic signals is encoded in the phase of transmitted surface plasmon polaritons (SPP). SPPs are excited at all three inputs and the phase of the output SPP is determined by theMAJof the input phases. The operating dimensions are identified and the functionality is verified for all input combinations. This is the first reported simulation of a plasmonic MAJ gate and thus contributes to the field of optical computing at the nanoscale. (C) 2017 Author(s). | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000404621200036 | Publication Date | 2017-06-23 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2158-3226 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | no | |||
| Call Number | UA @ admin @ c:irua:152632 | Serial | 7764 | ||
| Permanent link to this record | |||||
| Author | Ghorbanfekr-Kalashami, H.; Vasu, K.S.; Nair, R.R.; Peeters, F.M.; Neek-Amal, M. | ||||
| Title | Dependence of the shape of graphene nanobubbles on trapped substance | Type | A1 Journal article | ||
| Year |
2017 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
| Volume | 8 | Issue | 8 | Pages | 15844 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
| Abstract | Van der Waals (vdW) interaction between two-dimensional crystals (2D) can trap substances in high pressurized (of order 1 GPa) on nanobubbles. Increasing the adhesion between the 2D crystals further enhances the pressure and can lead to a phase transition of the trapped material. We found that the shape of the nanobubble can depend critically on the properties of the trapped substance. In the absence of any residual strain in the top 2D crystal, flat nanobubbles can be formed by trapped long hydrocarbons (that is, hexadecane). For large nanobubbles with radius 130 nm, our atomic force microscopy measurements show nanobubbles filled with hydrocarbons (water) have a cylindrical symmetry (asymmetric) shape which is in good agreement with our molecular dynamics simulations. This study provides insights into the effects of the specific material and the vdW pressure on the microscopic details of graphene bubbles. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000403417500001 | Publication Date | 2017-06-16 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.124 | Times cited | 44 | Open Access | |
| Notes | We acknowledge fruitful discussion with Irina Grigorieva and Andre K. Geim. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program, the Royal Society and the Engineering and Physical Sciences Research Council, UK (EP/K016946/1). M.N.-A. was supported by Iran National Science Foundation (INSF). | Approved | Most recent IF: 12.124 | ||
| Call Number | CMT @ cmt @ c:irua:144189 | Serial | 4580 | ||
| Permanent link to this record | |||||
| Author | Van Pottelberge, R.; Zarenia, M.; Vasilopoulos, P.; Peeters, F.M. | ||||
| Title | Graphene quantum dot with a Coulomb impurity : subcritical and supercritical regime | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 95 | Issue | 24 | Pages | 245410 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | We study the influence of confinement on the atomic collapse due to a Coulomb impurity placed at the center of a graphene quantum dot of radius R. We apply the zigzag or infinite-mass boundary condition and consider both a point-size and a finite-size impurity. As a function of the impurity strength Za, the energy spectra are discrete. In the case of the zigzag boundary condition, the degenerate (with respect to the angular momentum m) zero-energy levels are pulled down in energy as Z alpha increases, and they remain below epsilon = – Z alpha. Our results show that the energy levels exhibit a 1/R dependence in the subcritical regime [Z alpha < |km + 1/2|, k = 1 (-1) for the K (K') valley]. In the supercritical regime (Z alpha > |km + 1/2|) we find a qualitatively very different behavior where the levels decrease as a function of R in a nonmonotonic manner. While the valley symmetry is preserved in the presence of the impurity, we find that the impurity breaks electron-hole symmetry. We further study the energy spectrum of zigzag quantum dots in gapped graphene. Our results show that as the gap increases, the lowest electron states are pushed into the gap by the impurity. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
| Language | Wos | 000403072400005 | Publication Date | 2017-06-13 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 13 | Open Access | |
| Notes | ; We thank Massoud Ramezani-Masir and Dean Moldovan for fruitful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the Methusalem funding of the Flemish Government, and by the Canadian NSERC Grant No. OGP0121756 (P. V.). ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ lucian @ c:irua:144197 | Serial | 4661 | ||
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| Author | Yang, W.; Misko, V.R.; Tempère, J.; Kong, M.; Peeters, F.M. | ||||
| Title | Artificial living crystals in confined environment | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical Review E | Abbreviated Journal | Phys Rev E |
| Volume | 95 | Issue | 6 | Pages | 062602 |
| Keywords | A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) | ||||
| Abstract | Similar to the spontaneous formation of colonies of bacteria, flocks of birds, or schools of fish, “living crystals” can be formed by artificial self-propelled particles such as Janus colloids. Unlike usual solids, these “crystals” are far from thermodynamic equilibrium. They fluctuate in time forming a crystalline structure, breaking apart and re-forming again. We propose a method to stabilize living crystals by applying a weak confinement potential that does not suppress the ability of the particles to perform self-propelled motion, but it stabilizes the structure and shape of the dynamical clusters. This gives rise to such configurations of living crystals as “living shells” formed by Janus colloids. Moreover, the shape of the stable living clusters can be controlled by tuning the potential strength. Our proposal can be verified experimentally with either artificial microswimmers such as Janus colloids, or with living active matter. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000402667600006 | Publication Date | 2017-06-06 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2470-0045;2470-0053; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.366 | Times cited | 10 | Open Access | |
| Notes | ; This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Research Foundation (FWO-Vl) (Belgium), the Flemish Research Foundation (through Projects No. G.0115.12N, No. G.0119.12N, No. G.0122.12N, and No. G.0429.15N), and the Research Fund of the University of Antwerp. W.Y. acknowledges the support from the National Natural Science Foundation of China under Grants No. 11204199 and No. 51135007, the China Scholarship Council, the 131 project and the Program for the Outstanding Innovative Teams of Higher Learning Institutions of Shanxi, and a project under Grant No. 2016-096 by Shanxi Scholarship Council of China. ; | Approved | Most recent IF: 2.366 | ||
| Call Number | UA @ lucian @ c:irua:144205 | Serial | 4641 | ||
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| Author | Li, L.L.; Moldovan, D.; Vasilopoulos, P.; Peeters, F.M. | ||||
| Title | Aharonov-Bohm oscillations in phosphorene quantum rings | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 95 | Issue | 20 | Pages | 205426 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | The Aharonov-Bohm (AB) effect in square phosphorene quantum rings, with armchair and zigzag edges, is investigated using the tight-binding method. The energy spectra and wave functions of such rings, obtained as a function of the magnetic flux Phi threading the ring, are strongly influenced by the ringwidthW, an in-plane electric field E-p, and a side-gating potential V-g. Compared to a square dot, the ring shows an enhanced confinement due to its inner edges and an interedge coupling along the zigzag direction, both of which strongly affect the energy spectrum and the wave functions. The energy spectrum that is gapped consists of a regular part, of conduction (valence) band states, that shows the usual AB oscillations in the higher-(lower-) energy region, and of edge states, in the gap, that exhibit no AB oscillations. As the width W decreases, the AB oscillations become more distinct and regular and their period is close to Phi(0)/2, where the flux quantum Phi(0) = h/e is the period of an ideal circular ring (W -> 0). Both the electric field E-p and the side-gating potential V-g reduce the amplitude of the AB oscillations. The amplitude can be effectively tuned by E-p or V-g and exhibits an anisotropic behavior for different field directions or side-gating configurations. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
| Language | Wos | 000402003700010 | Publication Date | 2017-05-23 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 16 | Open Access | |
| Notes | ; This work was financially supported by the Chinese Academy of Sciences, the Flemish Science Foundation (FWO-V1), and by the Canadian NSERC Grant No. OGP0121756 (P.V.). ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ lucian @ c:irua:144267 | Serial | 4638 | ||
| Permanent link to this record | |||||
| Author | Saniz, R.; Bekaert, J.; Partoens, B.; Lamoen, D. | ||||
| Title | Structural and electronic properties of defects at grain boundaries in CuInSe2 | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 19 | Issue | 19 | Pages | 14770-14780 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract | We report on a first-principles study of the structural and electronic properties of a Sigma3 (112) grain boundary model in CuInSe2. The study focuses on a coherent, stoichiometry preserving, cation–Se terminated grain boundary, addressing the properties of the grain boundary as such, as well as the effect of well known defects in CuInSe2. We show that in spite of its apparent simplicity, such a grain boundary exhibits a very rich phenomenology, providing an explanation for several of the experimentally observed properties of grain boundaries in CuInSe2 thin films. In particular, we show that the combined effect of Cu vacancies and cation antisites can result in the observed Cu depletion with no In enrichment at the grain boundaries. Furthermore, Cu vacancies are unlikely to produce a hole barrier at the grain boundaries, but Na may indeed have such an effect. We find that Na-on-Cu defects will tend to form abundantly at the grain boundaries, and can provide a mechanism for the carrier depletion and/or type inversion experimentally reported. |
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000403327200059 | Publication Date | 2017-05-12 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 12 | Open Access | OpenAccess |
| Notes | We thank B. Schoeters for his assistance running the GBstudio software. We acknowledge the financial support of FWO-Vlaanderen through project G.0150.13. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by FWO-Vlaanderen and the Flemish Government-department EWI. | Approved | Most recent IF: 4.123 | ||
| Call Number | EMAT @ emat @ c:irua:143869 | Serial | 4577 | ||
| Permanent link to this record | |||||
| Author | de Sousa, G.O.; da Costa, D.R.; Chaves, A.; Farias, G.A.; Peeters, F.M. | ||||
| Title | Unusual quantum confined Stark effect and Aharonov-Bohm oscillations in semiconductor quantum rings with anisotropic effective masses | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 95 | Issue | 95 | Pages | 205414 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | The effects of external electric and magnetic fields on the energy spectrum of quantum rings made out of a bidimensional semiconductor material with anisotropic band structures are investigated within the effective-mass model. The interplay between the effective-mass anisotropy and the radial confinement leads to wave functions that are strongly localized at two diametrically opposite regions where the kinetic energy is lowest due to the highest effective mass. We show that this quantum phenomenon has clear consequences on the behavior of the energy states in the presence of applied in-plane electric fields and out-of-plane magnetic fields. In the former, the quantum confined Stark effect is observed with either linear or quadratic shifts, depending on the direction of the applied field. As for the latter, the usual Aharonov-Bohm oscillations are not observed for a circularly symmetric confining potential, however they can be reinstated if an elliptic ring with an appropriate aspect ratio is chosen. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
| Language | Wos | 000401230600007 | Publication Date | 2017-05-12 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 19 | Open Access | |
| Notes | ; This work was financially supported by CNPq under the PRONEX/FUNCAP grants, CAPES Foundation, the Flemish Science Foundation (FWO-Vl), and the Brazilian Program Science Without Borders (CsF). ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ lucian @ c:irua:143746 | Serial | 4610 | ||
| Permanent link to this record | |||||
| Author | Volodin, A.; Van Haesendonck, C.; Leenaerts, O.; Partoens, B.; Peeters, F.M. | ||||
| Title | Stress dependence of the suspended graphene work function : vacuum Kelvin probe force microscopy and density functional theory | Type | A1 Journal article | ||
| Year |
2017 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
| Volume | 110 | Issue | 19 | Pages | 193101 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | We report on work function measurements on graphene, which is exfoliated over a predefined array of wells in silicon oxide, by Kelvin probe force microscopy operating in a vacuum. The obtained graphene sealed microchambers can support large pressure differences, providing controllable stretching of the nearly impermeable graphene membranes. These measurements allow detecting variations of the work function induced by the mechanical stresses in the suspended graphene where the work function varies linearly with the strain and changes by 62 +/- 2 meV for 1 percent of strain. Our related ab initio calculations result in a work function variation that is a factor of 1.4 larger than the experimental value. The limited discrepancy between the theory and the experiment can be accounted for by a charge transfer from the unstrained to the strained graphene regions. Published by AIP Publishing. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
| Language | Wos | 000402319200036 | Publication Date | 2017-05-08 | |
| 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 | 8 | Open Access | |
| Notes | ; The authors wish to thank A. Klekachev (IMEC Leuven, Belgium) for the fabrication of the samples. This work was supported by the Science Foundation-Flanders (FWO, Belgium). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government-Department EWI. The Hercules Foundation also funded the scanning probe microscopy equipment. ; | Approved | Most recent IF: 3.411 | ||
| Call Number | UA @ lucian @ c:irua:144279 | Serial | 4690 | ||
| Permanent link to this record | |||||
| Author | Ozden, A.; Ay, F.; Sevik, C.; Perkgoz, N.K. | ||||
| Title | CVD growth of monolayer MoS2: Role of growth zone configuration and precursors ratio | Type | A1 Journal article | ||
| Year |
2017 | Publication | Japanese journal of applied physics | Abbreviated Journal | |
| Volume | 56 | Issue | 6s:[1] | Pages | 06gg05 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Single-layer, large-scale two-dimensional material growth is still a challenge for their wide-range usage. Therefore, we carried out a comprehensive study of monolayer MoS2 growth by CVD investigating the influence of growth zone configuration and precursors ratio. We first compared the two commonly used approaches regarding the relative substrate and precursor positions, namely, horizontal and face-down configurations where facedown approach is found to be more favorable to obtain larger flakes under identical growth conditions. Secondly, we used different types of substrate holders to investigate the influence of the Mo and S vapor confinement on the resulting diffusion environment. We suggest that local changes of the S to Mo vapor ratio in the growth zone is a key factor for the change of shape, size and uniformity of the resulting MoS2 formations, which is also confirmed by performing depositions under different precursor ratios. Therefore, to obtain continuous monolayer films, the S to Mo vapor ratio is needed to be kept within a certain range throughout the substrate. As a conclusion, we obtained monolayer triangles with a side length of 90 mu m and circles with a diameter of 500 mu m and continuous films with an area of 85 0 mu m x 1 cm when the S-to-Mo vapor ratio is optimized. (C) 2017 The Japan Society of Applied Physics | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000401059800003 | Publication Date | 2017-05-08 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-4922; 1347-4065 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | no | |||
| Call Number | UA @ admin @ c:irua:193783 | Serial | 7747 | ||
| Permanent link to this record | |||||
| Author | Leenaerts, O.; Vercauteren, S.; Partoens, B. | ||||
| Title | Band alignment of lateral two-dimensional heterostructures with a transverse dipole | Type | A1 Journal article | ||
| Year |
2017 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
| Volume | 110 | Issue | 110 | Pages | 181602 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | It was recently shown that the electronic band alignment in lateral two-dimensional heterostructures is strongly dependent on the system geometry, such as heterostructure width and layer thickness. This is so even in the absence of polar edge terminations because of the appearance of an interface dipole between the two different materials. In this study, this work is expanded to include two-dimensional materials that possess an electronic dipole over their surface, i.e., in the direction transverse to the crystal plane. To this end, a heterostucture consisting of polar hydrofluorinated graphene and non-polar graphane layers is studied with first-principles calculations. As for nonpolar heterostructures, a significant geometry dependence is observed with two different limits for the band offset. For infinitely wide heterostructures, the potential step in the vacuum is equally divided over the two sides of the heterostructure, resulting in a finite potential step in the heterostructure. For infinitely thick heterostructure slabs, on the other hand, the band offset is reduced, similar to the three-dimensional case. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
| Language | Wos | 000400931900014 | Publication Date | 2017-05-01 | |
| 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 | 4 | Open Access | |
| Notes | ; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-VI). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government-department EWI. ; | Approved | Most recent IF: 3.411 | ||
| Call Number | UA @ lucian @ c:irua:143755 | Serial | 4586 | ||
| Permanent link to this record | |||||
| Author | da Costa, D.R.; Chaves, A.; Farias, G.A.; Peeters, F.M. | ||||
| 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 | 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 | Mirzakhani, M.; Zarenia, M.; Vasilopoulos, P.; Peeters, F.M. | ||||
| Title | Electrostatically confined trilayer graphene quantum dots | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical review B | Abbreviated Journal | |
| Volume | 95 | Issue | 15 | Pages | 155434 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Electrically gating of trilayer graphene (TLG) opens a band gap offering the possibility to electrically engineer TLG quantum dots. We study the energy levels of such quantum dots and investigate their dependence on a perpendicular magnetic field B and different types of stacking of the graphene layers. The dots are modeled as circular and confined by a truncated parabolic potential which can be realized by nanostructured gates or position-dependent doping. The energy spectra exhibit the intervalley symmetry E-K(e) (m) = -E (h)(K') (m) for the electron (e) and hole (h) states, where m is the angular momentum quantum number and K and K' label the two valleys. The electron and hole spectra for B = 0 are twofold degenerate due to the intervalley symmetry E-K (m) = E-K' [-(m + 1)]. For both ABC [alpha = 1.5 (1.2) for large (small) R] and ABA (alpha = 1) stackings, the lowest-energy levels show approximately a R-alpha dependence on the dot radius R in contrast with the 1/R-3 one for ABC-stacked dots with infinite-mass boundary. As functions of the field B, the oscillator strengths for dipole-allowed transitions differ drastically for the two types of stackings. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000399797200003 | Publication Date | 2017-04-22 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | 6 | Open Access | ||
| Notes | Approved | no | |||
| Call Number | UA @ admin @ c:irua:152652 | Serial | 7878 | ||
| Permanent link to this record | |||||
| Author | Shayeganfar, F.; Vasu, K.S.; Nair, R.R.; Peeters, F.M.; Neek-Amal, M. | ||||
| Title | Monolayer alkali and transition-metal monoxides : MgO, CaO, MnO, and NiO | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical review B | Abbreviated Journal | |
| Volume | 95 | Issue | 14 | Pages | 144109 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Two-dimensional crystals with strong interactions between layers has attracted increasing attention in recent years in a variety of fields. In particular, the growth of a single layer of oxide materials (e.g., MgO, CaO, NiO, and MnO) over metallic substrates were found to display different physical properties than their bulk. In this study, we report on the physical properties of a single layer of metallic oxide materials and compare their properties with their bulk and other two-dimensional (2D) crystals. We found that the planar structure of metallic monoxides are unstable whereas the buckled structures are thermodynamically stable. Also, the 2D-MnO and NiO exhibit different magnetic (ferromagnetic) and optical properties than their bulk, whereas band-gap energy and linear stiffness are found to be decreasing from NiO to MgO. Our findings provide insight into oxide thin-film technology applications. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000399792400001 | Publication Date | 2017-04-20 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | 21 | Open Access | ||
| Notes | Approved | no | |||
| Call Number | UA @ admin @ c:irua:152654 | Serial | 8278 | ||
| Permanent link to this record | |||||
| Author | Magnus, W.; Lemmens, L.; Brosens, F. | ||||
| Title | Quantum canonical ensemble : a projection operator approach | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physica: A : theoretical and statistical physics | Abbreviated Journal | Physica A |
| Volume | 482 | Issue | Pages | 1-13 | |
| Keywords | A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) | ||||
| Abstract | Knowing the exact number of particles N, and taking this knowledge into account, the quantum canonical ensemble imposes a constraint on the occupation number operators. The constraint particularly hampers the systematic calculation of the partition function and any relevant thermodynamic expectation value for arbitrary but fixed N. On the other hand, fixing only the average number of particles, one may remove the above constraint and simply factorize the traces in Fock space into traces over single-particle states. As is well known, that would be the strategy of the grand-canonical ensemble which, however, comes with an additional Lagrange multiplier to impose the average number of particles. The appearance of this multiplier can be avoided by invoking a projection operator that enables a constraint-free computation of the partition function and its derived quantities in the canonical ensemble, at the price of an angular or contour integration. Introduced in the recent past to handle various issues related to particle-number projected statistics, the projection operator approach proves beneficial to a wide variety of problems in condensed matter physics for which the canonical ensemble offers a natural and appropriate environment. In this light, we present a systematic treatment of the canonical ensemble that embeds the projection operator into the formalism of second quantization while explicitly fixing N, the very number of particles rather than the average. Being applicable to both bosonic and fermionic systems in arbitrary dimensions, transparent integral representations are provided for the partition function Z(N) and the Helmholtz free energy F-N as well as for two- and four-point correlation functions. The chemical potential is not a Lagrange multiplier regulating the average particle number but can be extracted from FN+1 – F-N, as illustrated for a two-dimensional fermion gas. (C) 2017 Elsevier B.V. All rights reserved. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Amsterdam | Editor | ||
| Language | Wos | 000405885500001 | Publication Date | 2017-04-20 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0378-4371 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.243 | Times cited | 1 | Open Access | |
| Notes | ; ; | Approved | Most recent IF: 2.243 | ||
| Call Number | UA @ lucian @ c:irua:145145 | Serial | 4722 | ||
| Permanent link to this record | |||||
| Author | Zebrowski, D.P.; Peeters, F.M.; Szafran, B. | ||||
| Title | Driven spin transitions in fluorinated single- and bilayer-graphene quantum dots | Type | A1 Journal article | ||
| Year |
2017 | Publication | Semiconductor science and technology | Abbreviated Journal | Semicond Sci Tech |
| Volume | 32 | Issue | 6 | Pages | 065016 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Spin transitions driven by a periodically varying electric potential in dilute fluorinated graphene quantum dots are investigated. Flakes of monolayer graphene as well as electrostatic electron traps induced in bilayer graphene are considered. The stationary states obtained within the tight-binding approach are used as the basis for description of the system dynamics. The dilute fluorination of the top layer lifts the valley degeneracy of the confined states and attenuates the orbital magnetic dipole moments due to current circulation within the flake. The spin-orbit coupling introduced by the surface deformation of the top layer induced by the adatoms allows the spin flips to be driven by the AC electric field. For the bilayer quantum dots the spin flip times is substantially shorter than the spin relaxation. Dynamical effects including many-photon and multilevel transitions are also discussed. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | London | Editor | ||
| Language | Wos | 000402405800007 | Publication Date | 2017-04-19 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0268-1242 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 2.305 | Times cited | Open Access | ||
| Notes | ; This work was supported by the National Science Centre according to decision DEC-2013/11/B/ST3/03837 and by the Flemish Science Foundation (FWO-VL). ; | Approved | Most recent IF: 2.305 | ||
| Call Number | UA @ lucian @ c:irua:144238 | Serial | 4646 | ||
| Permanent link to this record | |||||
| Author | Houben, K.; Couet, S.; Trekels, M.; Menendez, E.; Peissker, T.; Seo, J.W.; Hu, M.Y.; Zhao, J.Y.; Alp, E.E.; Roelants, S.; Partoens, B.; Milošević, M.V.; Peeters, F.M.; Bessas, D.; Brown, S.A.; Vantomme, A.; Temst, K.; Van Bael, M.J. | ||||
| Title | Lattice dynamics in Sn nanoislands and cluster-assembled films | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 95 | Issue | 15 | Pages | 155413 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | To unravel the effects of phonon confinement, the influence of size and morphology on the atomic vibrations is investigated in Sn nanoislands and cluster-assembled films. Nuclear resonant inelastic x-ray scattering is used to probe the phonon densities of states of the Sn nanostructures which show significant broadening of the features compared to bulk phonon behavior. Supported by ab initio calculations, the broadening is attributed to phonon scattering and can be described within the damped harmonic oscillator model. Contrary to the expectations based on previous research, the appearance of high-energy modes above the cutoff energy is not observed. From the thermodynamic properties extracted from the phonon densities of states, it was found that grain boundary Sn atoms are bound by weaker forces than bulk Sn atoms. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
| Language | Wos | 000401762400008 | Publication Date | 2017-04-11 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 5 | Open Access | |
| Notes | ; This work was supported by the Research Foundation-Flanders (FWO) and the Concerted Research Action (GOA/14/007). The authors acknowledge Hercules stichting (Projects No. AKUL/13/19 and No. AKUL/13/25). K.H. and S.C. thank the FWO for financial support. T.P. acknowledges the IWT for financial support. S.R., M.V.M., and B.P. acknowledge TOPBOF funding of the University of Antwerp Research Fund. J.W.S. acknowledges Hercules Stichting (Project No. AKUL/13/19). The authors want to thank R. Lieten for help with the XRD measurements and T. Picot for fruitful discussions. The authors gratefully acknowledge R. Ruffer and A. I. Chumakov for fruitful discussions and the European Synchrotron Radiation Facility for the measurement of the SnO<INF>2</INF> powder at the Nuclear Resonance beamline (ID-18). This research used resources of the Advanced Photon Source, a US Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ lucian @ c:irua:144305 | Serial | 4667 | ||
| Permanent link to this record | |||||
| Author | Li, L.; Leenaerts, O.; Kong, X.; Chen, X.; Zhao, M.; Peeters, F.M. | ||||
| Title | Gallium bismuth halide GaBi-X2 (X = I, Br, Cl) monolayers with distorted hexagonal framework: Novel room-temperature quantum spin Hall insulators | Type | A1 Journal article | ||
| Year |
2017 | Publication | Nano Research | Abbreviated Journal | Nano Res |
| Volume | 10 | Issue | 10 | Pages | 2168-2180 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
| Abstract | Quantum spin Hall (QSH) insulators with a large topologically nontrivial bulk gap are crucial for future applications of the QSH effect. Among these, group III-V monolayers and their halides, which have a chair structure (regular hexagonal framework), have been widely studied. Using first-principles calculations, we formulate a new structure model for the functionalized group III-V monolayers, which consist of rectangular GaBi-X-2 (X = I, Br, Cl) monolayers with a distorted hexagonal framework (DHF). These structures have a far lower energy than the GaBi-X-2 monolayers with a chair structure. Remarkably, the DHF GaBi-X-2 monolayers are all QSH insulators, which exhibit sizeable nontrivial band gaps ranging from 0.17 to 0.39 eV. The band gaps can be widely tuned by applying different spin-orbit coupling strengths, resulting in a distorted Dirac cone. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000401320700029 | Publication Date | 2017-04-08 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1998-0124 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 7.354 | Times cited | 15 | Open Access | |
| Notes | ; This work was supported by the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation-Flanders (FWO) and the Flemish Government-department EWI. ; | Approved | Most recent IF: 7.354 | ||
| Call Number | UA @ lucian @ c:irua:143739 | Serial | 4598 | ||
| Permanent link to this record | |||||
| Author | Mulkers, J.; Van Waeyenberge, B.; Milošević, M.V. | ||||
| Title | Effects of spatially engineered Dzyaloshinskii-Moriya interaction in ferromagnetic films | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 95 | Issue | 95 | Pages | 144401 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | The Dzyaloshinskii-Moriya interaction (DMI) is a chiral interaction that favors formation of domain walls. Recent experiments and ab initio calculations show that there are multiple ways to modify the strength of the interfacially induced DMI in thin ferromagnetic films with perpendicular magnetic anisotropy. In this paper we reveal theoretically the effects of spatially varied DMI on the magnetic state in thin films. In such heterochiral 2D structures we report several emergent phenomena, ranging from the equilibrium spin canting at the interface between regions with different DMI, over particularly strong confinement of domain walls and skyrmions within high-DMI tracks, to advanced applications such as domain tailoring nearly at will, design of magnonic waveguides, and much improved skyrmion racetrack memory. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000399382100003 | Publication Date | 2017-04-03 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 60 | Open Access | |
| Notes | Fonds Wetenschappelijk Onderzoek, G098917N ; | Approved | Most recent IF: 3.836 | ||
| Call Number | CMT @ cmt @ c:irua:141917 | Serial | 4534 | ||
| Permanent link to this record | |||||
| Author | Petrovic, M.D.; Peeters, F.M. | ||||
| Title | Quantum transport in graphene Hall bars : effects of side gates | Type | A1 Journal article | ||
| Year |
2017 | Publication | Solid state communications | Abbreviated Journal | Solid State Commun |
| Volume | 257 | Issue | 257 | Pages | 20-26 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Quantum electron transport in side-gated graphene Hall bars is investigated in the presence of quantizing external magnetic fields. The asymmetric potential of four side-gates distorts the otherwise flat bands of the relativistic Landau levels, and creates new propagating states in the Landau spectrum (i.e. snake states). The existence of these new states leads to an interesting modification of the bend and Hall resistances, with new quantizing plateaus appearing in close proximity of the Landau levels. The electron guiding in this system can be understood by studying the current density profiles of the incoming and outgoing modes. From the fact that guided electrons fully transmit without any backscattering (similarly to edge states), we are able to analytically predict the values of the quantized resistances, and they match the resistance data we obtain with our numerical (tight-binding) method. These insights in the electron guiding will be useful in predicting the resistances for other side-gate configurations, and possibly in other system geometries, as long as there is no backscattering of the guided states. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | New York, N.Y. | Editor | ||
| Language | Wos | 000401101400005 | Publication Date | 2017-04-02 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0038-1098 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 1.554 | Times cited | Open Access | ||
| Notes | ; This work was supported by the Methusalem programme of the Flemish government. One of us (F. M. Peeters) acknowledges correspondence with K. Novoselov. ; | Approved | Most recent IF: 1.554 | ||
| Call Number | UA @ lucian @ c:irua:143761 | Serial | 4604 | ||
| Permanent link to this record | |||||
| Author | Zhao, H.J.; Misko, V.R.; Tempere, J.; Nori, F. | ||||
| Title | Pattern formation in vortex matter with pinning and frustrated intervortex interactions | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 95 | Issue | 95 | Pages | 104519 |
| Keywords | A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) | ||||
| Abstract | We investigate the effects related to vortex-core deformations when vortices approach each other. As a result of these vortex-core deformations, the vortex-vortex interaction effectively acquires an attractive component leading to a variety of vortex patterns typical for systems with nonmonotonic repulsive-attractive interaction, such as stripes and labyrinths. The core deformations are anisotropic and can induce frustration in the vortex-vortex interaction. In turn, this frustration has an impact on the resulting vortex patterns, which are analyzed in the presence of additional random pinning, as a function of the pinning strength. This analysis can be applicable to vortices in multiband superconductors or to vortices in Bose-Einstein condensates. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
| Language | Wos | 000399138800006 | Publication Date | 2017-03-30 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 5 | Open Access | |
| Notes | ; We acknowledge fruitful discussions with E. Babaev and V. Gladilin. This work is partially supported by the Natural Science Foundation of Jiangsu Province (Grant No. BK20150595), the National Natural Science Foundation of China (Grants No. NSFC-U1432135, No. 11611140101, and No. 11674054), the “Odysseus” program of the Flemish Government and Flemish Research Foundation (FWO-Vl), the Flemish Research Foundation (through Projects No. G.0115.12N, No. G.0119.12N, No. G.0122.12N, and No. G.0429.15N), the Research Fund of the University of Antwerp, the RIKEN iTHES Project, the MURI Center for Dynamic Magneto-Optics via the AFOSR Award No. FA9550-14-1-0040, the IMPACT program of JST, a Grant-in-Aid for Scientific Research (A), the Japan Society for the Promotion of Science (KAKENHI), CREST, and a grant from the John Templeton Foundation. ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ lucian @ c:irua:142429 | Serial | 4602 | ||
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| Author | Zarenia, M.; Neilson, D.; Partoens, B.; Peeters, F.M. | ||||
| Title | Wigner crystallization in transition metal dichalcogenides : a new approach to correlation energy | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 95 | Issue | 95 | Pages | 115438 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | We introduce a new approach for the correlation energy of one- and two-valley two-dimensional electron gas (2DEG) systems. Our approach is based on an interpolation between two limits, a random phase approximation at high densities and a classical approach at low densities which gives excellent agreement with available Quantum Monte Carlo (QMC) calculations. The two-valley 2DEG model is introduced to describe the electron correlations in monolayer transition metal dichalcogenides (TMDs). We study the zero-temperature transition from a Fermi liquid to a quantum Wigner crystal phase in monolayer TMDs. Consistent with QMC, we find that electrons crystallize at r(s) = 31 in one-valley 2DEG. For two valleys, we predict Wigner crystallization at r(s) = 30, implying that valley degeneracy has little effect on the critical r(s), in contrast to an earlier claim. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
| Language | Wos | 000399141200003 | Publication Date | 2017-03-30 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 18 | Open Access | |
| Notes | ; This work was partially supported by the Flanders Research Foundation (FWO) and the Methusalem program of the Flemish government. D.N. acknowledges support by the University of Camerino FAR project CESEMN. ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ lucian @ c:irua:142428 | Serial | 4613 | ||
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| Author | Willhammar, T.; Sentosun, K.; Mourdikoudis, S.; Goris, B.; Kurttepeli, M.; Bercx, M.; Lamoen, D.; Partoens, B.; Pastoriza-Santos, I.; Pérez-Juste, J.; Liz-Marzán, L.M.; Bals, S.; Van Tendeloo, G. | ||||
| Title | Structure and vacancy distribution in copper telluride nanoparticles influence plasmonic activity in the near-infrared | Type | A1 Journal article | ||
| Year |
2017 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
| Volume | 8 | Issue | 8 | Pages | 14925 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract | Copper chalcogenides find applications in different domains including photonics, photothermal therapy and photovoltaics. CuTe nanocrystals have been proposed as an alternative to noble metal particles for plasmonics. Although it is known that deviations from stoichiometry are a prerequisite for plasmonic activity in the near-infrared, an accurate description of the material and its (optical) properties is hindered by an insufficient understanding of the atomic structure and the influence of defects, especially for materials in their nanocrystalline form. We demonstrate that the structure of Cu1.5±xTe nanocrystals canbe determined using electron diffraction tomography. Real-space high-resolution electron tomography directly reveals the three-dimensional distribution of vacancies in the structure. Through first-principles density functional theory, we furthermore demonstrate that the influence of these vacancies on the optical properties of the nanocrystals is determined. Since our methodology is applicable to a variety of crystalline nanostructured materials, it is expected to provide unique insights concerning structure–property correlations. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000397799700001 | Publication Date | 2017-03-30 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 12.124 | Times cited | 37 | Open Access | OpenAccess |
| Notes | The work was financially supported by the European Research Council through an ERC Starting Grant (#335078-COLOURATOMS). T.W. acknowledges the Swedish Research Council for an international postdoc grant. We acknowledge financial support of FWO-Vlaanderen through project G.0216.14N, G.0369.15N and a postdoctoral research grant to B.G. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government–Department EWI. The work was further supported by the Spanish MINECO (MAT2013-45168-R). S.M. thanks the Action ooSupporting Postdoctoral Researchers44 of the Operational Program ‘Education and Lifelong Learning’ (Action’s Beneficiary: General Secretariat for Research and Technology of Greece), which was co-financed by the European Social Fund (ESF) and the Greek State. (ROMEO:green; preprint:; postprint:can ; pdfversion:can); ECAS_Sara | Approved | Most recent IF: 12.124 | ||
| Call Number | EMAT @ emat @ c:irua:142203UA @ admin @ c:irua:142203 | Serial | 4538 | ||
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| Author | Han, F.W.; Xu, W.; Li, L.L.; Zhang, C.; Dong, H.M.; Peeters, F.M. | ||||
| Title | Electronic and transport properties of n-type monolayer black phosphorus at low temperatures | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 95 | Issue | 95 | Pages | 115436 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | We present a detailed theoretical study of the electronic and transport properties of monolayer black phosphorus (BP). This study is motivated by recent experimental activities in investigating n-type few-layer BP systems. The electron density of states, the screening length, and the low-temperature electron mobility are calculated for monolayer BP (MLBP). In particular, the electron transport mobilities along the armchair and zigzag directions are examined on the basis of the momentum-balance equation derived from a semiclassical Boltzmann equation. The anisotropic electron mobilities in MLBP along different directions are demonstrated where the electron-impurity scattering is considered. Furthermore, we compare the results obtained from two electronic band structures of MLBP and find that the simplified model can describe quite rightly the electronic and transport properties of MLBP. This study is relevant to the application of few-layer BP based electronic systems as advanced electronic devices. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000399140700012 | Publication Date | 2017-03-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 12 | Open Access | |
| Notes | National Natural Science Foundation of China, 11574319 11304316 11304317 11604380 ; Ministry of Science and Technology of the People's Republic of China, 2011YQ130018 ; Chinese Academy of Sciences; | Approved | Most recent IF: 3.836 | ||
| Call Number | CMT @ cmt @ c:irua:142431 | Serial | 4564 | ||
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| Author | De Beule, C.; Zarenia, M.; Partoens, B. | ||||
| Title | Transmission in graphene-topological insulator heterostructures | Type | A1 Journal article | ||
| Year |
2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 95 | Issue | 95 | Pages | 115424 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | We investigate scattering of the topological surface state of a three-dimensional time-reversal invariant topological insulator when graphene is deposited on the topological-insulator surface. Specifically, we consider the (111) surface of a Bi2Se3-like topological insulator. We present a low-energy model for the graphene-topological insulator heterostructure and we calculate the transmission probability at zigzag and armchair edges of the deposited graphene, and the conductance through graphene nanoribbon barriers, and show that its features can be understood from antiresonances in the transmission probability. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
| Language | Wos | 000399216700004 | Publication Date | 2017-03-22 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 4 | Open Access | |
| Notes | ; The authors would like to thank B. Van Duppen for interesting discussions. This work was supported by the Flemish Research Foundation (FWO) through the Aspirant Fellowship of Christophe De Beule. ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ lucian @ c:irua:143652 | Serial | 4609 | ||
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