Records |
Author |
Suslu, A.; Wu, K.; Sahin, H.; Chen, B.; Yang, S.; Cai, H.; Aoki, T.; Horzum, S.; Kang, J.; Peeters, F.M.; Tongay, S.; |
Title |
Unusual dimensionality effects and surface charge density in 2D Mg(OH)2 |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
Volume |
6 |
Issue |
6 |
Pages |
20525 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
We present two-dimensional Mg(OH)(2) sheets and their vertical heterojunctions with CVD-MoS2 for the first time as flexible 2D insulators with anomalous lattice vibration and chemical and physical properties. New hydrothermal crystal growth technique enabled isolation of environmentally stable monolayer Mg(OH)(2) sheets. Raman spectroscopy and vibrational calculations reveal that the lattice vibrations of Mg(OH)(2) have fundamentally different signature peaks and dimensionality effects compared to other 2D material systems known to date. Sub-wavelength electron energy-loss spectroscopy measurements and theoretical calculations show that Mg(OH)(2) is a 6 eV direct-gap insulator in 2D, and its optical band gap displays strong band renormalization effects from monolayer to bulk, marking the first experimental confirmation of confinement effects in 2D insulators. Interestingly, 2D-Mg(OH)(2) sheets possess rather strong surface polarization (charge) effects which is in contrast to electrically neutral h-BN materials. Using 2D-Mg(OH)(2) sheets together with CVD-MoS2 in the vertical stacking shows that a strong change transfer occurs from n-doped CVD-MoS2 sheets to Mg(OH)(2), naturally depleting the semiconductor, pushing towards intrinsic doping limit and enhancing overall optical performance of 2D semiconductors. Results not only establish unusual confinement effects in 2D-Mg(OH)(2), but also offer novel 2D-insulating material with unique physical, vibrational, and chemical properties for potential applications in flexible optoelectronics. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000369510300001 |
Publication Date |
2016-02-05 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.259 |
Times cited |
39 |
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). HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus-short Marie Curie Fellowship. We acknowledge the use of John M. Cowley Center for High Resolution Electron Microscopy at Arizona State University. ; |
Approved |
Most recent IF: 4.259 |
Call Number |
UA @ lucian @ c:irua:131615 |
Serial |
4272 |
Permanent link to this record |
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Author |
Torun, E.; Sahin, H.; Peeters, F.M. |
Title |
Optical properties of GaS-Ca(OH)2 bilayer heterostructure |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
93 |
Issue |
93 |
Pages |
075111 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Finding novel atomically thin heterostructures and understanding their characteristic properties are critical for developing better nanoscale optoelectronic devices. In this study, we investigate the electronic and optical properties of a GaS-Ca(OH)(2) heterostructure using first-principle calculations. The band gap of the GaS-Ca(OH)(2) heterostructure is significantly reduced when compared to those of the isolated constituent layers. Our calculations showthat the GaS-Ca(OH)(2) heterostructure is a type-II heterojunction which can be used to separate photoinduced charge carriers where electrons are localized in GaS and holes in the Ca(OH)(2) layer. This leads to spatially indirect excitons which are important for solar energy and optoelectronic applications due to their long lifetime. By solving the Bethe-Salpeter equation on top of a single shot GW calculation (G(0)W(0)), the dielectric function and optical oscillator strength of the constituent monolayers and the heterostructure are obtained. The oscillator strength of the optical transition for the GaS monolayer is an order of magnitude larger than the Ca(OH)(2) monolayer. We also found that the calculated optical spectra of different stacking types of the heterostructure show dissimilarities, although their electronic structures are rather similar. This prediction can be used to determine the stacking type of ultrathin heterostructures. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000369401000001 |
Publication Date |
2016-02-06 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2469-9950;2469-9969; |
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 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 long Marie Curie Fellowship. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:131614 |
Serial |
4220 |
Permanent link to this record |
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Author |
Ozaydin, H.D.; Sahin, H.; Kang, J.; Peeters, F.M.; Senger, R.T. |
Title |
Electronic and magnetic properties of 1T-TiSe2 nanoribbons |
Type |
A1 Journal article |
Year |
2015 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
2 |
Issue |
2 |
Pages |
044002 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Motivated by the recent synthesis of single layer TiSe2, we used state-of-the-art density functional theory calculations, to investigate the structural and electronic properties of zigzag and armchair-edged nanoribbons (NRs) of this material. Our analysis reveals that, differing from ribbons of other ultra-thin materials such as graphene, TiSe2 NRs have some distinctive properties. The electronic band gap of the NRs decreases exponentially with the width and vanishes for ribbons wider than 20 angstrom. For ultranarrow zigzag-edged NRs we find odd-even oscillations in the band gap width, although their band structures show similar features. Moreover, our detailed magnetic-ground-state analysis reveals that zigzag and armchair edged ribbons have non-magnetic ground states. Passivating the dangling bonds with hydrogen at the edges of the structures influences the band dispersion. Our results shed light on the characteristic properties of T phase NRs of similar crystal structures. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000368936600005 |
Publication Date |
2015-10-13 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
20 |
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 ULAK-BIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus Short Marie Curie Fellowship. HDO, HS and RTS acknowledge the support from TUBITAK through project 114F397. ; |
Approved |
Most recent IF: 6.937; 2015 IF: NA |
Call Number |
UA @ lucian @ c:irua:131602 |
Serial |
4169 |
Permanent link to this record |
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|
Author |
Bogaerts, A.; Aghaei, M. |
Title |
What modeling reveals about the properties of an inductively coupled plasma |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Spectroscopy |
Abbreviated Journal |
Spectroscopy-Us |
Volume |
31 |
Issue |
1 |
Pages |
52-59 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
To get better performance from inductively coupled plasma (ICP)-based methods, it is informative to study the properties of the ICP under different conditions. Annemie Bogaerts and Maryam Aghaei at the University of Antwerp, Belgium, are using computational modeling to examine how various properties of the ICP, such as gas flow path lines and velocity, temperature changes, and ionization effects, are affected by numerous factors, such as the gas flow rates of injector and auxiliary gas, applied power, and even the very presence of a mass spectrometry (MS) sampler. They have also applied their models to study particle transport through the ICP. Using their developed model, it is now possible to predict optimum conditions for specific analyses. Bogaerts and Aghaei spoke to us about this work. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Springfield, Or. |
Editor |
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Language |
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Wos |
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Publication Date |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0887-6703 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
0.466 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 0.466 |
Call Number |
UA @ lucian @ c:irua:131601 |
Serial |
4278 |
Permanent link to this record |
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Author |
Zhang, B.; Dugas, R.; Rousse, G.; Rozier, P.; Abakumov, A.M.; Tarascon, J.-M. |
Title |
Insertion compounds and composites made by ball milling for advanced sodium-ion batteries |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
7 |
Issue |
7 |
Pages |
10308 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Sodium-ion batteries have been considered as potential candidates for stationary energy storage because of the low cost and wide availability of Na sources. However, their future commercialization depends critically on control over the solid electrolyte interface formation, as well as the degree of sodiation at the positive electrode. Here we report an easily scalable ball milling approach, which relies on the use of metallic sodium, to prepare a variety of sodium-based alloys, insertion layered oxides and polyanionic compounds having sodium in excess such as the Na4V2(PO4)(2)F-3 phase. The practical benefits of preparing sodium-enriched positive electrodes as reservoirs to compensate for sodium loss during solid electrolyte interphase formation are demonstrated by assembling full C/P'2-Na-1[Fe0.5Mn0.5]O-2 and C/'Na3+xV2(PO4)(2)F-3' sodium-ion cells that show substantial increases (>10%) in energy storage density. Our findings may offer electrode design principles for accelerating the development of the sodium-ion technology. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000369021400002 |
Publication Date |
2016-01-18 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
104 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 12.124 |
Call Number |
UA @ lucian @ c:irua:131599 |
Serial |
4197 |
Permanent link to this record |
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|
Author |
Calizzi, M.; Venturi, F.; Ponthieu, M.; Cuevas, F.; Morandi, V.; Perkisas, T.; Bals, S.; Pasquini, L. |
Title |
Gas-phase synthesis of Mg-Ti nanoparticles for solid-state hydrogen storage |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
Volume |
18 |
Issue |
18 |
Pages |
141-148 |
Keywords |
A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT) |
Abstract |
Mg-Ti nanostructured samples with different Ti contents were prepared via compaction of nanoparticles grown by inert gas condensation with independent Mg and Ti vapour sources. The growth set-up offered the option to perform in situ hydrogen absorption before compaction. Structural and morphological characterisation was carried out by X-ray diffraction, energy dispersive spectroscopy and electron microscopy. The formation of an extended metastable solid solution of Ti in hcp Mg was detected up to 15 at% Ti in the as-grown nanoparticles, while after in situ hydrogen absorption, phase separation between MgH2 and TiH2 was observed. At a Ti content of 22 at%, a metastable Mg-Ti-H fcc phase was observed after in situ hydrogen absorption. The co-evaporation of Mg and Ti inhibited nanoparticle coalescence and crystallite growth in comparison with the evaporation of Mg only. In situ hydrogen absorption was beneficial to subsequent hydrogen behaviour, studied by high pressure differential scanning calorimetry and isothermal kinetics. A transformed fraction of 90% was reached within 100 s at 300 degrees C during both hydrogen absorption and desorption. The enthalpy of hydride formation was not observed to differ from bulk MgH2. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000368755500014 |
Publication Date |
2015-11-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.123 |
Times cited |
31 |
Open Access |
Not_Open_Access |
Notes |
; Part of this work was supported by the COST Action MP1103 “Nanostructured materials for solid-state hydrogen storage”. ; |
Approved |
Most recent IF: 4.123 |
Call Number |
UA @ lucian @ c:irua:131589 |
Serial |
4184 |
Permanent link to this record |
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|
Author |
Fernández Becerra, V.; Sardella, E.; Peeters, F.M.; Milošević, M.V. |
Title |
Vortical versus skyrmionic states in mesoscopic p-wave superconductors |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
93 |
Issue |
93 |
Pages |
014518 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate the superconducting states that arise as a consequence of mesoscopic confinement and a multicomponent order parameter in the Ginzburg-Landau model for p-wave superconductivity. Conventional vortices, but also half-quantum vortices and skyrmions, are found as the applied magnetic field and the anisotropy parameters of the Fermi surface are varied. The solutions are well differentiated by a topological charge that for skyrmions is given by the Hopf invariant and for vortices by the circulation of the superconducting velocity. We revealed several unique states combining vortices and skyrmions, their possible reconfiguration with varied magnetic field, as well as temporal and field-induced transitions between vortical and skyrmionic states. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000369217400004 |
Publication Date |
2016-01-29 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
28 |
Open Access |
|
Notes |
; This work was supported by the Research Foundation – Flanders (FWO). E.S. acknowledges support from the Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP). ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:131581 |
Serial |
4275 |
Permanent link to this record |
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Author |
Cabral, L.R.E.; de Aquino, B.R.C.H.T.; de Souza Silva, C.C.; Milošević, M.V.; Peeters, F.M. |
Title |
Two-shell vortex and antivortex dynamics in a Corbino superconducting disk |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
93 |
Issue |
93 |
Pages |
014515 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We examine theoretically the dynamics of two vortex shells in pinning-free superconducting thin disks in the Corbino geometry. In the first considered case, the inner shell is composed of vortices and the outer one of antivortices, corresponding to a state induced by the stray field of an off-plane magnetic dipole placed on top of the superconductor. In the second considered case, both shells comprise vortices induced by a homogeneous external field. We derive the equation of motion for each shell within the Bardeen-Stephen model and study the dynamics analytically by assuming both shells are rigid and commensurate. In both cases, two distinct regimes for vortex shell motion are identified: For low applied currents the entire configuration rotates rigidly, while above a threshold current the shells decouple from each other and rotate at different angular velocities. Analytical expressions for the decoupling current, the recombination time in the decoupled phases, as well as the voltage-current characteristics are presented. Our analytical results are in excellent agreement with numerical molecular dynamics simulations of the full many-vortex problem. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000368481600003 |
Publication Date |
2016-01-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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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 |
7 |
Open Access |
|
Notes |
; This work was supported by the Brazilian Science Agencies CAPES, CNPq, and FACEPE under Grants No. APQ-1381-1.05/12, No. APQ 2017-1.05/12, and No. APQ-0598/1.05-08 and by EU-COST Action No. MP1201 and the Research Foundation-Flanders (FWO). ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:131541 |
Serial |
4270 |
Permanent link to this record |
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Author |
Brito, B.G.A.; Candido, L.; Hai, G.-Q.; Peeters, F.M. |
Title |
Quantum effects in a free-standing graphene lattice : path-integral against classical Monte Carlo simulations |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
92 |
Issue |
92 |
Pages |
195416 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In order to study quantum effects in a two-dimensional crystal lattice of a free-standing monolayer graphene, we have performed both path-integral Monte Carlo (PIMC) and classical Monte Carlo (MC) simulations for temperatures up to 2000 K. The REBO potential is used for the interatomic interaction. The total energy, interatomic distance, root-mean-square displacement of the atom vibrations, and the free energy of the graphene layer are calculated. The obtained lattice vibrational energy per atom from the classical MC simulation is very close to the energy of a three-dimensional harmonic oscillator 3k(B)T. The PIMC simulation shows that quantum effects due to zero-point vibrations are significant for temperatures T < 1000 K. The quantum contribution to the lattice vibrational energy becomes larger than that of the classical lattice for T < 400 K. The lattice expansion due to the zero-point motion causes an increase of 0.53% in the lattice parameter. A minimum in the lattice parameter appears at T similar or equal to 500 K. Quantum effects on the atomic vibration amplitude of the graphene lattice and its free energy are investigated. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000368095400004 |
Publication Date |
2015-11-13 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1098-0121; 1550-235x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
22 |
Open Access |
|
Notes |
; This research was supported by the Brazilian agencies FAPESP, FAPEG, and CNPq, the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
Call Number |
UA @ lucian @ c:irua:131144 |
Serial |
4232 |
Permanent link to this record |
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Author |
Ryabova, A.S.; Napolskiy, F.S.; Poux, T.; Istomin, S.Y.; Bonnefont, A.; Antipin, D.M.; Baranchikov, A.Y.; Levin, E.E.; Abakumov, A.M.; Kéranguéven, G.; Antipov, E.V.; Tsirlina, G.A.; Savinova, E.R.; |
Title |
Rationalizing the influence of the Mn(IV)/Mn(III) red-Ox transition on the electrocatalytic activity of manganese oxides in the oxygen reduction reaction |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Electrochimica acta |
Abbreviated Journal |
Electrochim Acta |
Volume |
187 |
Issue |
187 |
Pages |
161-172 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Knowledge on the mechanisms of oxygen reduction reaction (ORR) and descriptors linking the catalytic activity to the structural and electronic properties of transition metal oxides enable rational design of more efficient catalysts. In this work ORR electrocatalysis was studied on a set of single and complex Mn (III) oxides with a rotating disc electrode method and cyclic voltammetry. We discovered an exponential increase of the specific electrocatalytic activity with the potential of the surface Mn(IV)/Mn(III) red-ox couple, suggesting the latter as a new descriptor for the ORR electrocatalysis. The observed dependence is rationalized using a simple mean-field kinetic model considering availability of the Mn( III) centers and adsorbate-adsorbate interactions. We demonstrate an unprecedented activity of Mn2O3, ca. 40 times exceeding that of MnOOH and correlate the catalytic activity of Mn oxides to their crystal structure. (C) 2015 Elsevier Ltd. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000367235600019 |
Publication Date |
2015-11-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0013-4686 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.798 |
Times cited |
51 |
Open Access |
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Notes |
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Approved |
Most recent IF: 4.798 |
Call Number |
UA @ lucian @ c:irua:131096 |
Serial |
4237 |
Permanent link to this record |
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Author |
Rozova, M.G.; Grigoriev, V.V.; Bobrikov, I.A.; Filimonov, D.S.; Zakharov, K.V.; Volkova, O.S.; Vasiliev, A.N.; Antipov, E.V.; Tsirlin, A.A.; Abakumov, A.M. |
Title |
Synthesis, structure and magnetic ordering of the mullite-type Bi2Fe4-xCrxO9 solid solutions with a frustrated pentagonal Cairo lattice |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
Dalton T |
Volume |
45 |
Issue |
45 |
Pages |
1192-1200 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Highly homogeneous mullite-type solid solutions Bi2Fe4-xCrxO9 (x = 0.5, 1, 1.2) were synthesized using a soft chemistry technique followed by a solid-state reaction in Ar. The crystal structure of Bi2Fe3CrO9 was investigated using X-ray and neutron powder diffraction, transmission electron microscopy and Fe-57 Mossbauer spectroscopy (S.G. Pbam, a = 7.95579(9) angstrom , b = 8.39145(9) angstrom, c = 5.98242(7) angstrom, R-F(X-ray) = 0.022, R-F(neutron) = 0.057). The ab planes in the structure are tessellated with distorted pentagonal loops built up by three tetrahedrally coordinated Fe sites and two octahedrally coordinated Fe/Cr sites, linked together in the ab plane by corner-sharing forming a pentagonal Cairo lattice. Magnetic susceptibility measurements and powder neutron diffraction show that the compounds order antiferromagnetically (AFM) with the Neel temperatures decreasing upon increasing the Cr content from T-N similar to 250 K for x = 0 to T-N similar to 155 K for x = 1.2. The magnetic structure of Bi2Fe3CrO9 at T = 30 K is characterized by a propagation vector k = (1/2,1/2,1/2). The tetrahedrally coordinated Fe cations form singlet pairs within dimers of corner-sharing tetrahedra, but spins on the neighboring dimers are nearly orthogonal. The octahedrally coordinated (Fe, Cr) cations form antiferromagnetic up-up-down-down chains along c, while the spin arrangement in the ab plane is nearly orthogonal between nearest neighbors and collinear between second neighbors. The resulting magnetic structure is remarkably different from the one in pure Bi2Fe4O9 and features several types of spin correlations even on crystallographically equivalent exchange that may be caused by the simultaneous presence of Fe and Cr on the octahedral site. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
|
Wos |
000367614700041 |
Publication Date |
2015-11-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0300-9246; 1477-9226; 1472-7773 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.029 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:131095 |
Serial |
4257 |
Permanent link to this record |
|
|
|
Author |
Tahir, M.; Vasilopoulos, P.; Peeters, F.M. |
Title |
Quantum magnetotransport properties of a MoS2 monolayer |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
93 |
Issue |
93 |
Pages |
035406 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study transport properties of a MoS2 monolayer in the presence of a perpendicular magnetic field B. We derive and discuss its band structure and take into account spin and valley Zeeman effects. Compared to a conventional two-dimensional electron gas, these effects lead to new quantum Hall plateaus and new peaks in the longitudinal resistivity as functions of the magnetic field. The field B leads to a significant enhancement of the spin splitting in the conduction band, to a beating of the Shubnikov-de Haas (SdH) oscillations in the low-field regime, and to their splitting in the high-field regime. The Zeeman fields suppress significantly the beating of the SdH oscillations in the low-field regime and strongly enhance their splitting at high fields. The spin and valley polarizations show a similar beating pattern at low fields and are clearly separated at high fields in which they attain a value higher than 90%. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000367663500003 |
Publication Date |
2016-01-05 |
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 |
42 |
Open Access |
|
Notes |
; This work was supported by the Canadian NSERC Grant No. OGP0121756 (M.T., P.V.) and by the Flemish Science Foundation (FWO-Vl) (F.M.P.). ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:131093 |
Serial |
4233 |
Permanent link to this record |
|
|
|
Author |
Semkina, A.; Abakumov, M.; Grinenko, N.; Abakumov, A.; Skorikov, A.; Mironova, E.; Davydova, G.; Majouga, A.G.; Nukolova, N.; Kabanov, A.; Chekhonin, V.; |
Title |
Core-shell-corona doxorubicin-loaded superparamagnetic Fe3O4 nanoparticles for cancer theranostics |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Colloids and surfaces: B : biointerfaces |
Abbreviated Journal |
Colloid Surface B |
Volume |
136 |
Issue |
136 |
Pages |
1073-1080 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Superparamagnetic iron oxide magnetic nanoparticles (MNPs) are successfully used as contrast agents in magnetic-resonance imaging. They can be easily functionalized for drug delivery functions, demonstrating great potential for both imaging and therapeutic applications. Here we developed new pH-responsive theranostic core-shell-corona nanoparticles consisting of superparamagentic Fe3O4 core that displays high T2 relaxivity, bovine serum albumin (BSA) shell that binds anticancer drug, doxorubicin (Dox) and poly(ethylene glycol) (PEG) corona that increases stability and biocompatibility. The nanoparticles were produced by adsorption of the BSA shell onto the Fe3O4 core followed by crosslinking of the protein layer and subsequent grafting of the PEG corona using monoamino-terminated PEG via carbodiimide chemistry. The hydrodynamic diameter, zeta-potential, composition and T2 relaxivity of the resulting nanoparticles were characterized using transmission electron microscopy, dynamic light scattering, thermogravimetric analysis and T2-relaxometry. Nanoparticles were shown to absorb Dox molecules, possibly through a combination of electrostatic and hydrophobic interactions. The loading capacity (LC) of the nanoparticles was 8 wt.%. The Dox loaded nanoparticles release the drug at a higher rate at pH 5.5 compared to pH 7.4 and display similar cytotoxicity against C6 and HEK293 cells as the free Dox. (C) 2015 Elsevier B.V. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000367408100131 |
Publication Date |
2015-11-10 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0927-7765 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.887 |
Times cited |
37 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.887; 2015 IF: 4.152 |
Call Number |
UA @ lucian @ c:irua:131075 |
Serial |
4157 |
Permanent link to this record |
|
|
|
Author |
Kurttepeli, M. |
Title |
Carbon based materials and hybrid nanostructures investigated by advanced transmission electron microscopy |
Type |
Doctoral thesis |
Year |
2015 |
Publication |
|
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
Doctoral thesis; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Antwerpen |
Editor |
|
Language |
|
Wos |
|
Publication Date |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:130502 |
Serial |
4145 |
Permanent link to this record |
|
|
|
Author |
van Bockstal, L.; Mahy, M.; de Keyser, A.; Hoeks, W.; Herlach, F.; Peeters, F.M.; van de Graaf, W.; Borghs, G. |
Title |
Cyclotron-resonance of 2D electrons at Si-δ-doped InSb layers grown on GaAs |
Type |
A1 Journal article |
Year |
1995 |
Publication |
Physica: B : condensed matter |
Abbreviated Journal |
Physica B |
Volume |
211 |
Issue |
|
Pages |
455-457 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
A1995RD54400118 |
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4526 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.319 |
Times cited |
2 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:13038 |
Serial |
600 |
Permanent link to this record |
|
|
|
Author |
Marmorkos, I.K.; Matulis, A.; Peeters, F.M. |
Title |
Stability of the superconducting vortex structure around a magnetic dot |
Type |
A3 Journal article |
Year |
1995 |
Publication |
Physics of low-dimensional structures |
Abbreviated Journal |
|
Volume |
10/11 |
Issue |
|
Pages |
77-86 |
Keywords |
A3 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
|
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
PHYSICS, APPLIED 28/145 Q1 # |
Call Number |
UA @ lucian @ c:irua:13036 |
Serial |
3133 |
Permanent link to this record |
|
|
|
Author |
Charkin, D.O.; Akinfiev, V.S.; Alekseeva, A.M.; Batuk, M.; Abakumov, A.M.; Kazakov, S.M. |
Title |
Synthesis and cation distribution in the new bismuth oxyhalides with the Sillen-Aurivillius intergrowth structures |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
Dalton T |
Volume |
44 |
Issue |
44 |
Pages |
20568-20576 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
About 20 new compounds with the Sillen-Aurivillius intergrowth structure, (MeMeBi3Nb2O11X)-Me-1-Bi-2 (Me-1 = Pb, Sr, Ba; Me-2 = Ca, Sr, Ba; X = Cl, Br, I), have been prepared. They are composed of stacking of [ANb(2)O(7)] perovskite blocks, fluorite-type [M2O2] blocks and halogen sheets. The cation distribution between the fluorite and perovskite layers has been studied for Ba2Bi3Nb2O11I, Ca1.25Sr0.75Bi3Nb2O11Cl, BaCaBi3Nb2O11Br and Sr2Bi3Nb2O11Cl. The smaller Me cations tend to reside in the perovskite block while the larger ones are situated in the fluorite-type block. The distribution of the elements was confirmed for BaCaBi3Nb2O11Br using energy dispersive X-ray analysis combined with scanning transmission electron microscopy (STEM-EDX). An electron diffraction study of this compound reveals a local symmetry lowering caused by weakly correlated rotation of NbO6 octahedra. Based on our findings, we suggest a new stability criterion for mixed-layer structures, which is that net charges of any two consecutive layers do not compensate for each other and only the whole layer sequence is electroneutral. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000365411500036 |
Publication Date |
2015-10-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0300-9246; 1477-9226; 1472-7773 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.029 |
Times cited |
5 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:130330 |
Serial |
4256 |
Permanent link to this record |
|
|
|
Author |
Michel, K.H.; Costamagna; Peeters, F.M. |
Title |
Theory of thermal expansion in 2D crystals |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
Volume |
252 |
Issue |
252 |
Pages |
2433-2437 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The thermal expansion alpha(T) in layered crystals is of fundamental and technological interest. As suggested by I. M. Lifshitz in 1952, in thin solid films (crystalline membranes) a negative contribution to alpha(T) is due to anharmonic couplings between in-plane stretching modes and out-of-plane bending (flexural modes). Genuine in-plane anharmonicities give a positive contribution to alpha(T). The competition between these two effects can lead to a change of sign (crossover) from a negative value of alpha(T) in a temperature (T) range T <= T-alpha to a positive value of alpha(T) for T > T-alpha in layered crystals. Here, we present an analytical lattice dynamical theory of these phenomena for a two-dimensional (2D) hexagonal crystal. We start from a Hamiltonian that comprises anharmonic terms of third and fourth order in the lattice displacements. The in-plane and out-of-plane contributions to the thermal expansion are studied as functions of T for crystals of different sizes. Besides, renormalization of the flexural mode frequencies plays a crucial role in determining the crossover temperature T-alpha. Numerical examples are given for graphene where the anharmonic couplings are determined from experiments. The theory is applicable to other layer crystals wherever the anharmonic couplings are known. (C) 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Berlin |
Editor |
|
Language |
|
Wos |
000364690400014 |
Publication Date |
2015-08-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0370-1972 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.674 |
Times cited |
21 |
Open Access |
|
Notes |
; We thank B. Verberck, D. Lamoen, and A. Dobry for useful comments. We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. This work is supported by the Euro GRAPHENE project CONGRAN. ; |
Approved |
Most recent IF: 1.674; 2015 IF: 1.489 |
Call Number |
UA @ lucian @ c:irua:130281 |
Serial |
4264 |
Permanent link to this record |
|
|
|
Author |
Kang, J.; Horzum, S.; Peeters, F.M. |
Title |
Heterostructures of graphene and nitrogenated holey graphene: Moire pattern and Dirac ring |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
92 |
Issue |
92 |
Pages |
195419 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Nitrogenated holey graphene (NHG) is a recently synthesized two-dimensional material. In this paper the structural and electronic properties of heterostructures of graphene and NHG are investigated using first-principles and tight-binding calculations. Due to the lattice mismatch between NHG and graphene, the formation of a moire pattern is preferred in the graphene/NHG heterostructure, instead of a lattice-coherent structure. In moire-patterned graphene/NHG, the band gap opening at the K point is negligible, and the linear band dispersion of graphene survives. Applying an electric field modifies the coupling strength between the two atomic layers. The Fermi velocity upsilon(F) is reduced as compared to the one of pristine graphene, and its magnitude depends on the twist angle theta between graphene and NHG: For theta = 0 degrees, upsilon(F) is 30% of that of graphene, and it increases rapidly to a value of 80% with increasing theta. The heterostructure exhibits electron-hole asymmetry in upsilon(F), which is large for small theta. In NHG encapsulated between two graphene layers, a “Dirac ring” appears around the K point. Its presence is robust with respect to the relative stacking of the two graphene layers. These findings can be useful for future applications of graphene/NHG heterostructures. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000364998000006 |
Publication Date |
2015-11-19 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121; 1550-235x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
33 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
Call Number |
UA @ lucian @ c:irua:130266 |
Serial |
4189 |
Permanent link to this record |
|
|
|
Author |
Missault, N.; Vasilopoulos, P.; Vargiamidis, V.; Peeters, F.M.; Van Duppen, B. |
Title |
Spin- and valley-dependent transport through arrays of ferromagnetic silicene junctions |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
92 |
Issue |
92 |
Pages |
195423 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study ballistic transport of Dirac fermions in silicene through arrays of barriers, of width d, in the presence of an exchange field M and a tunable potential of height U or depth-U. The spin-and valley-resolved conductances as functions of U or M, exhibit resonances away from the Dirac point (DP) and close to it a pronounced dip that becomes a gap when a critical electric field E-z is applied. This gap widens by increasing the number of barriers and can be used to realize electric field-controlled switching of the current. The spin p(s) and valley p(v) polarizations of the current near the DP increase with Ez or M and can reach 100% for certain of their values. These field ranges widen significantly by increasing the number of barriers. Also, ps and pv oscillate nearly periodically with the separation between barriers or wells and can be inverted by reversing M. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000364998100006 |
Publication Date |
2015-11-20 |
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 |
54 |
Open Access |
|
Notes |
; This work was supported by the Canadian NSERC Grant No. OGP0121756 (P.V.) and by the Flemish Science Foundation (FWO-Vl) with a Ph.D. research grant (B.V.D.). ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
Call Number |
UA @ lucian @ c:irua:130264 |
Serial |
4247 |
Permanent link to this record |
|
|
|
Author |
Forsh, E.A.; Abakumov, A.M.; Zaytsev, V.B.; Konstantinova, E.A.; Forsh, P.A.; Rumyantseva, M.N.; Gaskov, A.M.; Kashkarov, P.K. |
Title |
Optical and photoelectrical properties of nanocrystalline indium oxide with small grains |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Thin solid films : an international journal on the science and technology of thin and thick films |
Abbreviated Journal |
Thin Solid Films |
Volume |
595 |
Issue |
595 |
Pages |
25-31 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Optical properties, spectral dependence of photoconductivity and photoconductivity decay in nanocrystalline indium oxide In2O3 are studied. A number of nanostructured In2O3 samples with various nanocrystals size are prepared by sol-gel method and characterized using various techniques. The mean nanocrystals size varies from 7 to 8 nm to 39-41 nm depending on the preparation conditions. Structural characterization of the In2O3 samples is performed by means of transmission electron microscopy and X-ray powder diffraction. The combined analysis of ultraviolet-visible absorption spectroscopy and diffuse reflectance spectroscopy shows that nanostructuring leads to the change in optical band gap: optical band gap of the In2O3 samples (with an average nanocrystal size from 7 to 41 nm) is equal to 2.8 eV. We find out the correlation between spectral dependence of photoconductivity and optical properties of nanocrystalline In2O3: sharp increase in photoconductivity was observed to begin at 2.8 eV that is equal to the optical bandgap in the In2O3 samples, and reached its maximum at 3.2-3.3 eV. The combined analysis of the slow photoconductivity decay in air, vacuum and argon, that was accurately fitted by a stretched-exponential function, and electron paramagnetic resonance (EPR) measurements shows that the kinetics of photoconductivity decay is strongly depended on the presence of oxygen molecules in the ambient of In2O3 nanocrystals. There is the quantitative correlation between EPR and photoconductivity data. Based on the obtained data we propose the model clearing up the phenomenon of permanent photoconductivity decay in nanocrystalline In2O3. (C) 2015 Elsevier B.V. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
000365812400005 |
Publication Date |
2015-10-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0040-6090 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.879 |
Times cited |
18 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.879; 2015 IF: 1.759 |
Call Number |
UA @ lucian @ c:irua:130254 |
Serial |
4219 |
Permanent link to this record |
|
|
|
Author |
Van Aelst, J.; Verboekend, D.; Philippaerts, A.; Nuttens, N.; Kurttepeli, M.; Gobechiya, E.; Haouas, M.; Sree, S.P.; Denayer, J.F.M.; Martens, J.A.; Kirschhock, C.E.A.; Taulelle, F.; Bals, S.; Baron, G.V.; Jacobs, P.A.; Sels, B.F. |
Title |
Catalyst design by NH4OH treatment of USY zeolite |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
Volume |
25 |
Issue |
25 |
Pages |
7130-7144 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Hierarchical zeolites are a class of superior catalysts which couples the intrinsic zeolitic properties to enhanced accessibility and intracrystalline mass transport to and from the active sites. The design of hierarchical USY (Ultra-Stable Y) catalysts is achieved using a sustainable postsynthetic room temperature treatment with mildly alkaline NH4OH ( 0.02(M)) solutions. Starting from a commercial dealuminated USY zeolite (Si/Al = 47), a hierarchical material is obtained by selective and tuneable creation of interconnected and accessible small mesopores (2- 6 nm). In addition, the treatment immediately yields the NH4+ form without the need for additional ion exchange. After NH4OH modification, the crystal morphology is retained, whereas the microporosity and relative crystallinity are decreased. The gradual formation of dense amorphous phases throughout the crystal without significant framework atom leaching rationalizes the very high material yields (>90%). The superior catalytic performance of the developed hierarchical zeolites is demonstrated in the acid-catalyzed isomerization of alpha-pinene and the metal-catalyzed conjugation of safflower oil. Significant improvements in activity and selectivity are attained, as well as a lowered susceptibility to deactivation. The catalytic performance is intimately related to the introduced mesopores, hence enhanced mass transport capacity, and the retained intrinsic zeolitic properties. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000366503700003 |
Publication Date |
2015-10-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1616-301x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
64 |
Open Access |
OpenAccess |
Notes |
; The authors thank Dr. M. Thommes and Dr. K. Cychosz for numerous and helpful discussions on the correct evaluation of the Ar isotherms. I. Cuppens is acknowledged for ICP-AES analyses. Research was funded through a PhD grant to J.V.A. of the Agency for Innovation by Science and Technology in Flanders (IWT). D.V. and A.P. acknowledge F.W.O.-Vlaanderen (Research Foundation Flanders) for a postdoctoral fellowship. N.N. thanks the KU Leuven for financial support (FLOF). E.G., C.K., and J.M. acknowledge the long-term structural funding by the Flemish Government (Methusalem). S.B. acknowledges the European Research Council for funding under the European Union's Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement No. 335078-COLOURATOMS. The authors are grateful for financial support by the Belgian government through Interuniversity Attraction Poles (IAP-PAI). They also thank Oleon NV for supplying safflower oil. ; ecas_Sara |
Approved |
Most recent IF: 12.124; 2015 IF: 11.805 |
Call Number |
UA @ lucian @ c:irua:130214 |
Serial |
4147 |
Permanent link to this record |
|
|
|
Author |
Ercolani, G.; Gorle, C.; Garcia Sánchez, C.; Corbari, C.; Mancini, M. |
Title |
RAMS and WRF sensitivity to grid spacing in large-eddy simulations of the dry convective boundary layer |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Computers and fluids |
Abbreviated Journal |
Comput Fluids |
Volume |
123 |
Issue |
123 |
Pages |
54-71 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Large-eddy simulations (LESS) are frequently used to model the planetary boundary layer, and the choice of the grid cell size, numerical schemes and sub grid model can significantly influence the simulation results. In the present paper the impact of grid spacing on LES of an idealized atmospheric convective boundary layer (CBL), for which the statistics and flow structures are well understood, is assessed for two mesoscale models: the Regional Atmospheric Modeling System (RAMS) and the Weather Research and Forecasting model (WRF). Nine simulations are performed on a fixed computational domain (6 x 6 x 2 km), combining three different horizontal (120, 60, 30 m) and vertical (20, 10, 5 m) spacings. The impact of the cell size on the CBL is investigated by comparing turbulence statistics and velocity spectra. The results demonstrate that both WRF and RAMS can perform LES of the CBL under consideration without requiring extremely high computational loads, but they also indicate the importance of adopting a computational grid that is adequate for the numerical schemes and subgrid models used. In both RAMS and WRF a horizontal cell size of 30 m is required to obtain a suitable turbulence reproduction throughout the CBL height. Considering the vertical grid spacing, WRF produced similar results for all the three tested values, while in RAMS it should be ensured that the aspect ratio of the cells does not exceed a value of 3. The two models were found to behave differently in function of the grid resolution, and they have different shortcomings in their prediction of CBL turbulence. WRF exhibits enhanced damping at the smallest scales, while RAMS is prone to the appearance of spurious fluctuations in the flow when the grid aspect ratio is too high. (C) 2015 Elsevier Ltd. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000365367500006 |
Publication Date |
2015-10-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0045-7930 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.313 |
Times cited |
3 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.313; 2015 IF: 1.619 |
Call Number |
UA @ lucian @ c:irua:130200 |
Serial |
4236 |
Permanent link to this record |
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Author |
Van Tendeloo, G.; op de Beeck, M.; De Meulenaere, P.; van Dyck, D. |
Title |
Towards quantitative high resolution electron microscopy? |
Type |
A1 Journal article |
Year |
1995 |
Publication |
Institute of physics conference series |
Abbreviated Journal |
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Volume |
147 |
Issue |
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Pages |
67-72 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
The basics of the interpretation of high resolution images showing detail of the order of 0.1 nm are shortly explained here. The use of a field emission source, a CCD camera and an adapted reconstruction method for restoring the projected crystal potential (focus variation method) allows a quantitative interpretation of HREM images. Examples of partially disordered alloys and carbonate ordering in high Tc superconductors are presented. |
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Corporate Author |
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Publisher |
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Place of Publication |
London |
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Wos |
A1995BE67F00014 |
Publication Date |
0000-00-00 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0-7503-0357-3; 0951-3248; 0305-2346 |
ISBN |
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Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ lucian @ c:irua:13015 |
Serial |
3688 |
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Author |
Bogaerts, A.; Khosravian, N.; Van der Paal, J.; Verlackt, C.C.W.; Yusupov, M.; Kamaraj, B.; Neyts, E.C. |
Title |
Multi-level molecular modelling for plasma medicine |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Journal Of Physics D-Applied Physics |
Abbreviated Journal |
J Phys D Appl Phys |
Volume |
49 |
Issue |
5 |
Pages |
054002-54019 |
Keywords |
A1 Journal article; Plasma, laser ablation and surface modeling – Antwerp (PLASMANT) |
Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record |
Impact Factor |
2.588 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 2.588 |
Call Number |
UA @ lucian @ c:irua:129798 |
Serial |
4467 |
Permanent link to this record |
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Author |
de Sousa, A.A.; Chaves, A.; Pereira, T.A.S.; Farias, G.A.; Peeters, F.M. |
Title |
Quantum tunneling between bent semiconductor nanowires |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
118 |
Issue |
118 |
Pages |
174301 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We theoretically investigate the electronic transport properties of two closely spaced L-shaped semiconductor quantum wires, for different configurations of the output channel widths as well as the distance between the wires. Within the effective-mass approximation, we solve the time-dependent Schrodinger equation using the split-operator technique that allows us to calculate the transmission probability, the total probability current, the conductance, and the wave function scattering between the energy subbands. We determine the maximum distance between the quantum wires below which a relevant non-zero transmission is still found. The transmission probability and the conductance show a strong dependence on the width of the output channel for small distances between the wires. (C) 2015 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000364584200020 |
Publication Date |
2015-11-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979; 1089-7550 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
7 |
Open Access |
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Notes |
; A. A. Sousa was financially supported by CAPES, under the PDSE Contract No. BEX 7177/13-5. T. A. S. Pereira was financially supported by PRONEX/CNPq/FAPEMAT 850109/2009 and by CAPES under process BEX 3299/13-9. This work was financially supported by PRONEX/CNPq/FUNCAP, the Science Without Borders program and the bilateral project CNPq-FWO. ; |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:129544 |
Serial |
4234 |
Permanent link to this record |
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Author |
Croitoru, M.D.; Shanenko, A.A.; Vagov, A.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. |
Title |
Phonon limited superconducting correlations in metallic nanograins |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
Volume |
5 |
Issue |
5 |
Pages |
16515 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Conventional superconductivity is inevitably suppressed in ultra-small metallic grains for characteristic sizes smaller than the Anderson limit. Experiments have shown that above the Anderson limit the critical temperature may be either enhanced or reduced when decreasing the particle size, depending on the superconducting material. In addition, there is experimental evidence that whether an enhancement or a reduction is found depends on the strength of the electronphonon interaction in the bulk. We reveal how the strength of the e-ph interaction interplays with the quantum-size effect and theoretically obtain the critical temperature of the superconducting nanograins in excellent agreement with experimental data. We demonstrate that strong e-ph scattering smears the peak structure in the electronic density-of-states of a metallic grain and enhances the electron mass, and thereby limits the highest T-c achievable by quantum confinement. |
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Corporate Author |
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Thesis |
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Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
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Language |
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Wos |
000364647700001 |
Publication Date |
2015-11-13 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2045-2322 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.259 |
Times cited |
9 |
Open Access |
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Notes |
; This work was supported by the Belgian Science Policy (BELSPO Back to Belgium Grant), the Research Foundation Flanders (FWO), the Methusalem Foundation of the Flemish Government, TOPBOF-UA, and the bilateral project CNPq-FWO. M.D.C. acknowledges fruitful discussions with V. Z. Kresin, S. N. Klimin and V. N. Gladilin. ; |
Approved |
Most recent IF: 4.259; 2015 IF: 5.578 |
Call Number |
UA @ lucian @ c:irua:129543 |
Serial |
4224 |
Permanent link to this record |
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Author |
Sun, Z.; Madej, E.; Wiktor; Sinev, I.; Fischer, R.A.; Van Tendeloo, G.; Muhler, M.; Schuhmann, W.; Ventosa, E. |
Title |
One-pot synthesis of carbon-coated nanostructured iron oxide on few-layer graphene for lithium-ion batteries |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Chemistry: a European journal |
Abbreviated Journal |
Chem-Eur J |
Volume |
21 |
Issue |
21 |
Pages |
16154-16161 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Nanostructure engineering has been demonstrated to improve the electrochemical performance of iron oxide based electrodes in Li-ion batteries (LIBs). However, the synthesis of advanced functional materials often requires multiple steps. Herein, we present a facile one-pot synthesis of carbon-coated nanostructured iron oxide on few-layer graphene through high-pressure pyrolysis of ferrocene in the presence of pristine graphene. The ferrocene precursor supplies both iron and carbon to form the carbon-coated iron oxide, while the graphene acts as a high-surface-area anchor to achieve small metal oxide nanoparticles. When evaluated as a negative-electrode material for LIBs, our composite showed improved electrochemical performance compared to commercial iron oxide nanopowders, especially at fast charge/discharge rates. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
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Language |
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Wos |
000363890700036 |
Publication Date |
2015-09-11 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0947-6539 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.317 |
Times cited |
8 |
Open Access |
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Notes |
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Approved |
Most recent IF: 5.317; 2015 IF: 5.731 |
Call Number |
UA @ lucian @ c:irua:129510 |
Serial |
4218 |
Permanent link to this record |
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Author |
Berdiyorov, G.R.; Savel'ev, S.; Kusmartsev, F.V.; Peeters, F.M. |
Title |
Effect of ordered array of magnetic dots on the dynamics of Josephson vortices in stacked SNS Josephson junctions under DC and AC current |
Type |
A1 Journal article |
Year |
2015 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
Volume |
88 |
Issue |
88 |
Pages |
286 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We use the anisotropic time-dependent Ginzburg-Landau theory to investigate the effect of a square array of out-of-plane magnetic dots on the dynamics of Josephson vortices (fluxons) in artificial stacks of superconducting-normal-superconducting (SNS) Josephson junctions in the presence of external DC and AC currents. Periodic pinning due to the magnetic dots distorts the triangular lattice of fluxons and results in the appearance of commensurability features in the current-voltage characteristics of the system. For the larger values of the magnetization, additional peaks appear in the voltage-time characteristics of the system due to the creation and annihilation of vortex-antivortex pairs. Peculiar changes in the response of the system to the applied current is found resulting in a “superradiant” vortex-flow state at large current values, where a rectangular lattice of moving vortices is formed. Synchronizing the motion of fluxons by adding a small ac component to the biasing dc current is realized. However, we found that synchronization becomes difficult for large magnetization of the dots due to the formation of vortex-antivortex pairs. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000363960900002 |
Publication Date |
2015-10-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1434-6028 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.461 |
Times cited |
1 |
Open Access |
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Notes |
; This work was supported by EU Marie Curie (Project No. 253057). ; |
Approved |
Most recent IF: 1.461; 2015 IF: 1.345 |
Call Number |
UA @ lucian @ c:irua:129509 |
Serial |
4166 |
Permanent link to this record |
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Author |
Kang, J.; Sahin, H.; Peeters, F.M. |
Title |
Mechanical properties of monolayer sulphides : a comparative study between MoS2, HfS2 and TiS3 |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
Volume |
17 |
Issue |
17 |
Pages |
27742-27749 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The in-plane stiffness (C), Poisson's ratio (nu), Young's modulus and ultimate strength (sigma) along two different crystallographic orientations are calculated for the single layer crystals: MoS2, HfS2 and TiS3 in 1H, 1T and monoclinic phases. We find that MoS2 and HfS2 have isotropic in-plane stiffnesses of 124.24 N m(-1) and 79.86 N m(-1), respectively. While for TiS3 the in-plane stiffness is highly anisotropic due to its monoclinic structure, with C-x = 83.33 N m(-1) and C-y = 133.56 N m(-1) (x and y are parallel to its longer and shorter in-plane lattice vectors.). HfS2 which is in the 1T phase has the smallest anisotropy in its ultimate strength, whereas TiS3 in the monoclinic phase has the largest. Along the armchair direction MoS2 has the largest sigma of 23.48 GPa, whereas along y TiS3 has the largest sigma of 18.32 GPa. We have further analyzed the band gap response of these materials under uniaxial tensile strain, and find that they exhibit different behavior. Along both armchair and zigzag directions, the band gap of MoS2 (HfS2) decreases (increases) as strain increases, and the response is almost isotropic. For TiS3, the band gap decreases when strain is along x, while if strain is along y, the band gap increases first and then decreases beyond a threshold strain value. The different characteristics observed in these sulphides with different structures shed light on the relationship between the structure and properties, which is useful for applications in nanotechnology. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000363193800055 |
Publication Date |
2015-09-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1463-9076 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.123 |
Times cited |
83 |
Open Access |
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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 Super-computer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus-Long Marie Curie Fellowship, and J.K. by a FWO Pegasus-Short Marie Curie Fellowship. ; |
Approved |
Most recent IF: 4.123; 2015 IF: 4.493 |
Call Number |
UA @ lucian @ c:irua:129478 |
Serial |
4204 |
Permanent link to this record |