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Records |
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Author |
Ramos, I.R.O.; Ferreira, W.P.; Munarin, F.F.; Farias, G.A.; Peeters, F.M. |
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Title |
Bilayer crystals of charged magnetic dipoles : structure and phonon spectrum |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : E : statistical, nonlinear, and soft matter physics |
Abbreviated Journal |
Phys Rev E |
| |
Volume |
85 |
Issue |
5:1 |
Pages |
051404-051404,12 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We study the structure and phonon spectrum of a two-dimensional bilayer system of classical charged dipoles oriented perpendicular to the plane of the layers for equal density in each layer. This system can be tuned through six different crystalline phases by changing the interlayer separation or the charge and/or dipole moment of the particle. The presence of the charge on the dipole particles is responsible for the nucleation of five staggered phases and a disordered phase which are not found in the magnetic dipole bilayer system. These extra phases are a consequence of the competition between the repulsive Coulomb and the attractive dipole interlayer interaction. We present the phase diagram and determine the order of the phase transitions. The phonon spectrum of the system was calculated within the harmonic approximation, and a nonmonotonic behavior of the phonon spectrum is found as a function of the effective strength of the interparticle interaction. The stability of the different phases is determined. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
Woodbury (NY) |
Editor |
|
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Language |
|
Wos |
000304403400002 |
Publication Date |
2012-05-30 |
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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 |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1539-3755;1550-2376; |
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 CNPq, CAPES, and FUNCAP (PRONEX grant), the Flemish Science Foundation (FWO-Vl), the bilateral program between Flanders and Brazil, and the CNPq-FWO collaborating project. The authors are grateful to Prof. G. Goldoni for some technical clarifications concerning Ref. [18]. ; |
Approved |
Most recent IF: 2.366; 2012 IF: 2.313 |
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Call Number |
UA @ lucian @ c:irua:98940 |
Serial |
233 |
| Permanent link to this record |
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Author |
Badalyan, S.M.; Peeters, F.M. |
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Title |
Effect of nonhomogenous dielectric background on the plasmon modes in graphene double-layer structures at finite temperatures |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
85 |
Issue |
19 |
Pages |
195444-195444,6 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
We have calculated the plasmon modes in graphene double layer structures at finite temperatures, taking into account the inhomogeneity of the dielectric background of the system. The effective dielectric function is obtained from the solution of the Poisson equation of a three-layer dielectric medium with graphene sheets located at the interfaces, separating the different materials. Due to the momentum dispersion of the effective dielectric function, the intra- and interlayer bare Coulomb interactions in the graphene double layer system acquires an additional momentum dependence-an effect that is of the order of the interlayer interaction itself. We show that the energies of the in-phase and out-of-phase plasmon modes are determined largely by different values of the spatially dependent effective dielectric function. The effect of the dielectric inhomogeneity increases with temperature, and even at high temperatures the energy shift induced by the dielectric inhomogeneity and temperature itself remains larger than the broadening of the plasmon energy dispersions due to the Landau damping. The obtained new features of the plasmon dispersions can be observed in frictional drag measurements and in inelastic light scattering and electron energy-loss spectroscopies. |
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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 |
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Editor |
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Language |
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Wos |
000304394800011 |
Publication Date |
2012-05-23 |
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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 |
|
Series Issue |
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Edition |
|
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ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
67 |
Open Access |
|
| |
Notes |
; We thank G. Vignale for useful discussions and acknowledge support from the Flemisch Science Foundation (FWO-Fl) and the Belgian Science Policy (BELSPO). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:98941 |
Serial |
826 |
| Permanent link to this record |
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Author |
Neek-Amal, M.; Peeters, F.M. |
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Title |
Strain-engineered graphene through a nanostructured substrate : 1 : deformations |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
85 |
Issue |
19 |
Pages |
195445-195445,11 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Using atomistic simulations we investigate the morphological properties of graphene deposited on top of a nanostructured substrate. Sinusoidally corrugated surfaces, steps, elongated trenches, one-dimensional and cubic barriers, spherical bubbles, Gaussian bumps, and Gaussian depressions are considered as support structures for graphene. The graphene-substrate interaction is governed by van der Waals forces and the profile of the graphene layer is determined by minimizing the energy using molecular dynamics simulations. Based on the obtained optimum configurations, we found that (i) for graphene placed over sinusoidally corrugated substrates with corrugation wavelengths longer than 2 nm, the graphene sheet follows the substrate pattern while for supported graphene it is always suspended across the peaks of the substrate, (ii) the conformation of graphene to the substrate topography is enhanced when increasing the energy parameter in the van der Waals model, (iii) the adhesion of graphene into the trenches depends on the width of the trench and on the graphene's orientation, i. e., in contrast to a small-width (3 nm) nanoribbon with armchair edges, the one with zigzag edges follows the substrate profile, (iv) atomic-scale graphene follows a Gaussian bump substrate but not the substrate with a Gaussian depression, and (v) the adhesion energy due to van der Waals interaction varies in the range [0.1-0.4] J/m(2). |
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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 |
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Editor |
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Language |
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Wos |
000304394800012 |
Publication Date |
2012-05-23 |
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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 |
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Edition |
|
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ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
62 |
Open Access |
|
| |
Notes |
; We thank L. Covaci and S. Costamagna for valuable comments. We acknowledge M. Zarenia, M. R. Masir and D. Nasr for fruitful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl) and ESF EUROCORE program EuroGRAPHENE: CONGRAN. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:98942 |
Serial |
3166 |
| Permanent link to this record |
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Author |
Neek-Amal, M.; Peeters, F.M. |
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Title |
Strain-engineered graphene through a nanostructured substrate : 2 : pseudomagnetic fields |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
85 |
Issue |
19 |
Pages |
195446-195446,6 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The strain-induced pseudomagnetic field in supported graphene deposited on top of a nanostructured substrate is investigated by using atomistic simulations. A step, an elongated trench, a one-dimensional barrier, a spherical bubble, a Gaussian bump, and a Gaussian depression are considered as support structures for graphene. From the obtained optimum configurations we found very strong induced pseudomagnetic fields which can reach up to similar to 1000 T due to the strain-induced deformations in the supported graphene. Different magnetic confinements with controllable geometries are found by tuning the pattern of the substrate. The resulting induced magnetic fields for graphene on top of a step, barrier, and trench are calculated. In contrast to the step and trench the middle part of graphene on top of a barrier has zero pseudomagnetic field. This study provides a theoretical background for designing magnetic structures in graphene by nanostructuring substrates. We found that altering the radial symmetry of the deformation changes the sixfold symmetry of the induced pseudomagnetic field. |
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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 |
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Editor |
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Language |
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Wos |
000304394800013 |
Publication Date |
2012-05-23 |
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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 |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
31 |
Open Access |
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the ESF EUROCORE program EuroGRAPHENE: CONGRAN. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:98943 |
Serial |
3167 |
| Permanent link to this record |
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Author |
Komendová, L.; Chen, Y.; Shanenko, A.A.; Milošević, M.V.; Peeters, F.M. |
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Title |
Two-band superconductors : hidden criticality deep in the superconducting state |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
| |
Volume |
108 |
Issue |
20 |
Pages |
207002-207002,5 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We show that two-band superconductors harbor hidden criticality deep in the superconducting state, stemming from the critical temperature of the weaker band taken as an independent system. For sufficiently small interband coupling gamma the coherence length of the weaker band exhibits a remarkable deviation from the conventional monotonic increase with temperature, namely, a pronounced peak close to the hidden critical point. The magnitude of the peak scales as proportional to gamma(-mu), with the Landau critical exponent mu = 1/3, the same as found for the mean-field critical behavior with respect to the source field in ferromagnets and ferroelectrics. Here reported hidden criticality of multiband superconductors can be experimentally observed by, e.g., imaging of the variations of the vortex core in a broader temperature range. Similar effects are expected for the superconducting multilayers. |
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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 |
New York, N.Y. |
Editor |
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Language |
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Wos |
000304064000017 |
Publication Date |
2012-05-15 |
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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 |
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Edition |
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ISSN |
0031-9007;1079-7114; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.462 |
Times cited |
75 |
Open Access |
|
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). Useful discussions with A. V. Vagov are acknowledged. ; |
Approved |
Most recent IF: 8.462; 2012 IF: 7.943 |
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Call Number |
UA @ lucian @ c:irua:98945 |
Serial |
3770 |
| Permanent link to this record |
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Author |
Grimaldi, G.; Leo, A.; Nigro, A.; Silhanek, A.V.; Verellen, N.; Moshchalkov, V.V.; Milošević, M.V.; Casaburi, A.; Cristiano, R.; Pace, S. |
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Title |
Controlling flux flow dissipation by changing flux pinning in superconducting films |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
100 |
Issue |
20 |
Pages |
202601-202601,4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We study the flux flow state in superconducting materials characterized by rather strong intrinsic pinning, such as Nb, NbN, and nanostructured Al thin films, in which we drag the superconducting dissipative state into the normal state by current biasing. We modify the vortex pinning strength either by ion irradiation, by tuning the measuring temperature or by including artificial pinning centers. We measure critical flux flow voltages for all materials and the same effect is observed: switching to low flux flow dissipations at low fields for an intermediate pinning regime. This mechanism offers a way to additionally promote the stability of the superconducting state. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4718309] |
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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 |
000304265000051 |
Publication Date |
2012-05-14 |
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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 |
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Edition |
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ISSN |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
33 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
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Call Number |
UA @ lucian @ c:irua:98946 |
Serial |
504 |
| Permanent link to this record |
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Author |
Palgrave, R.G.; Borisov, P.; Dyer, M.S.; McMitchell, S.R.C.; Darling, G.R.; Claridge, J.B.; Batuk, M.; Tan, H.; Tian, H.; Verbeeck, J.; Hadermann, J.; Rosseinsky, M.J.; |
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Title |
Artificial construction of the layered Ruddlesden-Popper manganite La2Sr2Mn3O10 by reflection high energy electron diffraction monitored pulsed laser deposition |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
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Volume |
134 |
Issue |
18 |
Pages |
7700-7714 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Pulsed laser deposition has been used to artificially construct the n = 3 Ruddlesden Popper structure La2Sr2Mn3O10 in epitaxial thin film form by sequentially layering La1-xSrxMnO3 and SrO unit cells aided by in situ reflection high energy electron diffraction monitoring. The interval deposition technique was used to promote two-dimensional SrO growth. X-ray diffraction and cross-sectional transmission electron microscopy indicated that the trilayer structure had been formed. A site ordering was found to differ from that expected thermodynamically, with the smaller Sr2+ predominantly on the R site due to kinetic trapping of the deposited cation sequence. A dependence of the out-of-plane lattice parameter on growth pressure was interpreted as changing the oxygen content of the films. Magnetic and transport measurements on fully oxygenated films indicated a frustrated magnetic ground state characterized as a spin glass-like magnetic phase with the glass temperature T-g approximate to 34 K. The magnetic frustration has a clear in-plane (ab) magnetic anisotropy, which is maintained up to temperatures of 150 K. Density functional theory calculations suggest competing antiferromagnetic and ferromagnetic long-range orders, which are proposed as the origin of the low-temperature glassy state. |
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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 |
Washington, D.C. |
Editor |
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Language |
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Wos |
000303696200029 |
Publication Date |
2012-03-30 |
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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 |
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Edition |
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ISSN |
0002-7863;1520-5126; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
13.858 |
Times cited |
27 |
Open Access |
|
| |
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 13.858; 2012 IF: 10.677 |
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Call Number |
UA @ lucian @ c:irua:98947UA @ admin @ c:irua:98947 |
Serial |
153 |
| Permanent link to this record |
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Author |
Silhanek, A.V.; Leo, A.; Grimaldi, G.; Berdiyorov, G.R.; Milošević, M.V.; Nigro, A.; Pace, S.; Verellen, N.; Gillijns, W.; Metlushko, V.; Ilić, B.; Zhu, X.; Moshchalkov, V.V.; |
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Title |
Influence of artificial pinning on vortex lattice instability in superconducting films |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
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Volume |
14 |
Issue |
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Pages |
053006-053006,11 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
In superconducting films under an applied dc current, we analyze experimentally and theoretically the influence of engineered pinning on the vortex velocity at which the flux-flow dissipation undergoes an abrupt transition from low to high resistance. We argue, based on a nonuniform distribution of vortex velocity in the sample, that in strongly disordered systems the mean critical vortex velocity for flux-flow instability (i) has a nonmonotonic dependence on magnetic field and (ii) decreases as the pinning strength is increased. These findings challenge the generally accepted microscopic model of Larkin and Ovchinnikov (1979 J. Low. Temp. Phys. 34 409) and all subsequent refinements of this model which ignore the presence of pinning centers. |
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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 |
Bristol |
Editor |
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Language |
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Wos |
000304871700003 |
Publication Date |
2012-05-04 |
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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 |
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Edition |
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ISSN |
1367-2630; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.786 |
Times cited |
40 |
Open Access |
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Notes |
; This work was supported by the Methusalem Funding of the Flemish Government, the ESF-NES program, the Belgian Science Policy (IAP) and the Fund for Scientific Research-Flanders (FWO-Vlaanderen). AVS, GRB and WG received individual support from FWO-Vlaanderen. GG acknowledges support from the research project L.R. N5 of Regione Campania. VM acknowledges financial support from the US NSF, grant no. ECCS-0823813. We acknowledge J Van de Vondel for a critical reading of the manuscript. ; |
Approved |
Most recent IF: 3.786; 2012 IF: 4.063 |
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Call Number |
UA @ lucian @ c:irua:98949 |
Serial |
1616 |
| Permanent link to this record |
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Author |
Chen, Y.; Shanenko, A.A.; Peeters, F.M. |
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Title |
Superconducting transition temperature of Pb nanofilms : impact of thickness-dependent oscillations of the phonon-mediated electron-electron coupling |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
22 |
Pages |
224517-224517,6 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
To date, several experimental groups reported measurements of the thickness dependence of T-c of atomically uniform single-crystalline Pb nanofilms. The reported amplitude of the T-c oscillations varies significantly from one experiment to another. Here we propose that the reason for this unresolved issue is an interplay of the quantum-size variations in the single-electron density of states with thickness-dependent oscillations in the phonon-mediated electron-electron coupling. Such oscillations in the coupling depend on the substrate material, the quality of the interface, the protection cover, and other details of the fabrication process, changing from one experiment to another. This explains why the available data do not exhibit one-voice consistency about the amplitude of the T-c oscillations. Our analyses are based on a numerical solution of the Bogoliubov-de Gennes equations for a superconducting slab. |
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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 |
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Editor |
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Language |
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Wos |
000305251300006 |
Publication Date |
2012-06-14 |
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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 |
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Edition |
|
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ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
24 |
Open Access |
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:99076 |
Serial |
3368 |
| Permanent link to this record |
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Author |
Zarenia, M.; Vasilopoulos, P.; Peeters, F.M. |
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Title |
Magnetotransport in periodically modulated bilayer graphene |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
24 |
Pages |
245426-245426,10 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Magnetotransport in bilayer graphene in the presence of a weak and periodic potential is investigated in the presence of a perpendicular magnetic field B. The modulation broadens the Landau levels into bands and for weak magnetic fields leads to the well-known Weiss oscillations in their bandwidth and their transport coefficients at very low B and to the Shubnikov-de Haas oscillations at larger B. The amplitude of the Weiss oscillations is severely reduced if the periodic potentials applied to the two layers oscillate out of phase. We also contrast some results with those corresponding to single-layer graphene. Relative to them the flat-band condition and the oscillation amplitude differ substantially, due to the interlayer coupling, and agree only when this coupling is extremely weak. We further show that the Hall conductivity exhibits the well-known steps at half-integer and integer multiples of 4e(2)/h in single-layer and bilayer graphene, respectively, even for very weak magnetic fields. The results are pertinent to weak and periodic corrugations when the potential modulation dominates the strain-induced magnetic modulation. |
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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 |
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Editor |
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Language |
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Wos |
000305253600012 |
Publication Date |
2012-06-14 |
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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 |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
21 |
Open Access |
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES program EuroGRAPHENE (project CON-GRAN), and the Canadian NSERC Grant No. OGP0121756. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| |
Call Number |
UA @ lucian @ c:irua:99077 |
Serial |
1934 |
| Permanent link to this record |
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Author |
Dendooven, J.; Goris, B.; Devloo-Casier, K.; Levrau, E.; Biermans, E.; Baklanov, M.R.; Ludwig, K.F.; van der Voort, P.; Bals, S.; Detavernier, C. |
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Title |
Tuning the pore size of ink-bottle mesopores by atomic layer deposition |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
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Volume |
24 |
Issue |
11 |
Pages |
1992-1994 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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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 |
Washington, D.C. |
Editor |
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Language |
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Wos |
000305092600002 |
Publication Date |
2012-05-03 |
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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 |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
9.466 |
Times cited |
52 |
Open Access |
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
| |
Call Number |
UA @ lucian @ c:irua:99078 |
Serial |
3760 |
| Permanent link to this record |
| |
|
| |
|
Author |
Neyts, E.C.; Thijsse, B.J.; Mees, M.J.; Bal, K.M.; Pourtois, G. |
| |
Title |
Establishing uniform acceptance in force biased Monte Carlo simulations |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of chemical theory and computation |
Abbreviated Journal |
J Chem Theory Comput |
| |
Volume |
8 |
Issue |
6 |
Pages |
1865-1869 |
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
Uniform acceptance force biased Monte Carlo (UFMC) simulations have previously been shown to be a powerful tool to simulate atomic scale processes, enabling one to follow the dynamical path during the simulation. In this contribution, we present a simple proof to demonstrate that this uniform acceptance still complies with the condition of detailed balance, on the condition that the characteristic parameter lambda = 1/2 and that the maximum allowed step size is chosen to be sufficiently small. Furthermore, the relation to Metropolis Monte Carlo (MMC) is also established, and it is shown that UFMC reduces to MMC by choosing the characteristic parameter lambda = 0 [Rao, M. et al. Mol. Phys. 1979, 37, 1773]. Finally, a simple example compares the UFMC and MMC methods. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000305092400002 |
Publication Date |
2012-05-16 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1549-9618;1549-9626; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
5.245 |
Times cited |
20 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 5.245; 2012 IF: 5.389 |
| |
Call Number |
UA @ lucian @ c:irua:99090 |
Serial |
1082 |
| Permanent link to this record |
| |
|
| |
|
Author |
Scarrozza, M.; Pourtois, G.; Houssa, M.; Heyns, M.; Stesmans, A. |
| |
Title |
Oxidation of the GaAs(001) surface : insights from first-principles calculations |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
85 |
Issue |
19 |
Pages |
195307-195307,8 |
| |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| |
Abstract |
We performed a detailed investigation of the oxidation of the technologically relevant GaAs(001)-beta 2(2x4) surface via density functional calculations. The purpose is to gain insights on the atomistic mechanisms and local bondings that underlie the degradation of the surface properties once exposed to oxygen. The study comprises the adsorption of single O atoms, through the sampling of several adsorption sites, and the subsequent formation of the O adsorbate at increasing coverage by taking into account multiple-atom adsorption. Based on the evaluation of the energetics and the structural properties of the atomistic models generated, the results here reported delineate a consistent picture of the initial stage of the surface oxidation: (i) at low coverage, in the limit of single O insertions, oxygen is incorporated on the surface forming a twofold-bridging Ga-O-As bond; (ii) at increasing coverage, as multiple O atoms are involved, this is accompanied by the formation of a threefold-coordinated bond (with two Ga and one As atoms); (iii) the latter has important implications regarding the electronic properties of the adsorbate since this O bonding may result in the formation of As dangling bonds. Moreover, a clear trend of increased energy gain for the incorporation of neighboring O atoms compared to single O insertions indicates that the formation of oxide clusters is favored over a regime of uniform oxidation. Our findings provide a detailed description of the O bonding and stress the importance of modeling the adsorption of multiple O atoms for an accurate description of the surface oxidation. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000303755700006 |
Publication Date |
2012-05-08 |
| |
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 |
15 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| |
Call Number |
UA @ lucian @ c:irua:99122 |
Serial |
2538 |
| Permanent link to this record |
| |
|
| |
|
Author |
Lajevardipour, A.; Neek-Amal, M.; Peeters, F.M. |
| |
Title |
Thermomechanical properties of graphene : valence force field model approach |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
| |
Volume |
24 |
Issue |
17 |
Pages |
175303-175303,8 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Using the valence force field model of Perebeinos and Tersoff (2009 Phys. Rev. B 79 241409(R)), different energy modes of suspended graphene subjected to tensile or compressive strain are studied. By carrying out Monte Carlo simulations it is found that: (i) only for small strains (vertical bar epsilon vertical bar (sic) 0.02) is the total energy symmetrical in the strain, while it behaves completely differently beyond this threshold; (ii) the important energy contributions in stretching experiments are stretching, angle bending, an out-of-plane term, and a term that provides repulsion against pi-pi misalignment; (iii) in compressing experiments the two latter terms increase rapidly, and beyond the buckling transition stretching and bending energies are found to be constant; (iv) from stretching-compressing simulations we calculated the Young's modulus at room temperature 350 +/- 3.15 N m(-1), which is in good agreement with experimental results (340 +/- 50 N m(-1)) and with ab initio results (322-353) N m(-1); (v) molar heat capacity is estimated to be 24.64 J mol(-1) K-1 which is comparable with the Dulong-Petit value, i. e. 24.94 J mol(-1) K-1, and is almost independent of the strain; (vi) nonlinear scaling properties are obtained from height-height correlations at finite temperature; (vii) the used valence force field model results in a temperature independent bending modulus for graphene, and (viii) the Gruneisen parameter is estimated to be 0.64. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
London |
Editor |
|
| |
Language |
|
Wos |
000303499700012 |
Publication Date |
2012-04-05 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.649 |
Times cited |
29 |
Open Access |
|
| |
Notes |
; We acknowledge helpful comments by V Perebeinos, S Costamagna, A Fasolino and J H Los. This work was supported by the Flemish science foundation (FWO-Vl) and the Belgium Science Policy (IAP). ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
| |
Call Number |
UA @ lucian @ c:irua:99123 |
Serial |
3639 |
| Permanent link to this record |
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|
| |
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Author |
Barbier, M.; Papp, G.; Peeters, F.M. |
| |
Title |
Snake states and Klein tunneling in a graphene Hall bar with a pn-junction |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| |
Volume |
100 |
Issue |
16 |
Pages |
163121-163121,3 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The Hall (R-H) and bend (R-B) resistances of a graphene Hall bar structure containing a pn-junction are calculated when in the ballistic regime. The simulations are done using the billiard model. Introducing a pn-junction-dividing the Hall bar geometry in two regions-leads to two distinct regimes exhibiting very different physics: (1) both regions are of n-type and (2) one region is n-type and the other p-type. In regime (1), a “Hall plateau”-an enhancement of the resistance-appears for R-H. On the other hand, in regime (2), we found a negative R-H, which approaches zero for large B. The bend resistance is highly asymmetric in regime (2) and the resistance increases with increasing magnetic field B in one direction while it reduces to zero in the other direction. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4704667] |
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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| |
Language |
|
Wos |
000303128500064 |
Publication Date |
2012-04-20 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.411 |
Times cited |
20 |
Open Access |
|
| |
Notes |
; This work was supported by IMEC, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-EuroGRAPHENE project CONGRAN. ; |
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
| |
Call Number |
UA @ lucian @ c:irua:99129 |
Serial |
3047 |
| Permanent link to this record |
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| |
|
Author |
Arsoski, V.; Čukarić, N.; Tadić, M.; Peeters, F.M. |
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Title |
Exciton states in a nanocup in the presence of a perpendicular magnetic field |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physica scripta |
Abbreviated Journal |
Phys Scripta |
| |
Volume |
T149 |
Issue |
|
Pages |
014054-014054,5 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The exciton states in a strained (In,Ga)As/GaAs nanocup are theoretically determined. We explore how the nanocup bottom thickness (t) affects the magnetic field dependence of the exciton energy. Strain distribution is computed by the continuum mechanical model under the approximation of isotropic elasticity. The exciton wave functions are expanded into products of the electron and hole envelope functions. For small t, the exciton ground state has zero orbital momentum and exhibits small oscillations of the second derivative when the magnetic field increases. When t approaches the value of the cup height, however, the exciton levels exhibit angular momentum transitions, whose behavior is similar to that for type-II quantum dots. Small oscillations of the oscillator strength for exciton recombination are found when the magnetic field increases. An increase in thickness of the nanocup bottom has only a small effect on those oscillations for the optically active exciton states, but the exciton ground state becomes dark when the magnetic field increases. Hence, the results of our calculations show that an increase in thickness of the nanocup bottom transforms the exciton ground energy level dependence on magnetic field from the one characteristic of type-I rings to the one characteristic of type-II dots. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Stockholm |
Editor |
|
| |
Language |
|
Wos |
000303523500055 |
Publication Date |
2012-04-27 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0031-8949;1402-4896; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
1.28 |
Times cited |
2 |
Open Access |
|
| |
Notes |
; This work was supported by the EU Network of Excellence SANDiE, the Ministry of Education and Science of Serbia, the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 1.28; 2012 IF: 1.032 |
| |
Call Number |
UA @ lucian @ c:irua:99135 |
Serial |
1117 |
| Permanent link to this record |
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| |
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Author |
Grujić, M.; Zarenia, M.; Tadić, M.; Peeters, F.M. |
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Title |
Interband optical absorption in a circular graphene quantum dot |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physica scripta |
Abbreviated Journal |
Phys Scripta |
| |
Volume |
T149 |
Issue |
|
Pages |
014056-014056,4 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
We investigate the energy levels and optical properties of a circular graphene quantum dot in the presence of an external magnetic field perpendicular to the dot. Based on the Dirac-Weyl equation and assuming zero outward current at the edge of the dot we present the results for two different types of boundary conditions, i.e. infinite-mass (IMBC) and zigzag boundary conditions. We found that the dot with zigzag edges displays a zero-energy state in the energy spectra while this is not the case for the IMBCs. For both boundary conditions, the confinement becomes dominated by the magnetic field, where the energy levels converge to the Landau levels as the magnetic field increases. The effect of boundary conditions on the electron-and hole-energy states is found to affect the interband absorption spectra, where we found larger absorption in the case of IMBCs. The selection rules for interband optical transitions are determined and discussed for both boundary conditions. |
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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
Stockholm |
Editor |
|
| |
Language |
|
Wos |
000303523500057 |
Publication Date |
2012-04-27 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0031-8949;1402-4896; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
1.28 |
Times cited |
5 |
Open Access |
|
| |
Notes |
; This work was supported by the EuroGraphene program of the ESF (project CONGRAN), the Ministry of Education and Science of Serbia, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 1.28; 2012 IF: 1.032 |
| |
Call Number |
UA @ lucian @ c:irua:99136 |
Serial |
1688 |
| Permanent link to this record |
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|
Author |
Bertrand, L.; Robinet, L.; Thoury, M.; Janssens, K.; Cohen, S.X.; Schöder, S. |
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Title |
Cultural heritage and archaeology materials studied by synchrotron spectroscopy and imaging |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Applied physics A : materials science & processing |
Abbreviated Journal |
Appl Phys A-Mater |
| |
Volume |
106 |
Issue |
2 |
Pages |
377-396 |
| |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| |
Abstract |
The use of synchrotron radiation techniques to study cultural heritage and archaeological materials has undergone a steep increase over the past 10-15 years. The range of materials studied is very broad and encompasses painting materials, stone, glass, ceramics, metals, cellulosic and wooden materials, and a cluster of organic-based materials, in phase with the diversity observed at archaeological sites, museums, historical buildings, etc. Main areas of investigation are: (1) the study of the alteration and corrosion processes, for which the unique non-destructive speciation capabilities of X-ray absorption have proved very beneficial, (2) the understanding of the technologies and identification of the raw materials used to produce archaeological artefacts and art objects and, to a lesser extent, (3) the investigation of current or novel stabilisation, conservation and restoration practices. In terms of the synchrotron methods used, the main focus so far has been on X-ray techniques, primarily X-ray fluorescence, absorption and diffraction, and Fourier-transform infrared spectroscopy. We review here the use of these techniques from recent works published in the field demonstrating the breadth of applications and future potential offered by third generation synchrotron techniques. New developments in imaging and advanced spectroscopy, included in the UV/visible and IR ranges, could even broaden the variety of materials studied, in particular by fostering more studies on organic and complex organic-inorganic mixtures, while new support activities at synchrotron facilities might facilitate transfer of knowledge between synchrotron specialists and users from archaeology and cultural heritage sciences. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000299749000009 |
Publication Date |
2011-11-25 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0947-8396 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
1.455 |
Times cited |
55 |
Open Access |
|
| |
Notes |
; The authors acknowledge the critical reading by B. Berrie (National Gallery of Art, Washington DC, USA). We thank J. Mass (Conservation Department, Winterthur Museum and Country Estate, Winterthur, DE, USA), H. Roemich (Institute of Fine Arts, New York University, USA), J. Hiller (Non-Crystalline Diffraction Beamline, Diamond Light Source, Didcot, UK) and J.-P. Echard (Laboratoire de recherche et de restauration, Musee de la musique, Paris, France) for their comments on the presentation of their work in the manuscript. The IPANEMA platform is jointly developed by CNRS, MNHN, the French Ministry of Culture and Communication and SOLEIL, and benefits from a CPER grant (MESR, Region Ile-de-France). Support by the Access to Research Infrastructures activity in the 7th Framework Programme of the EU (CHARISMA Grant Agreement n. 228330) and the NWO Science4Arts programme are acknowledged. ; |
Approved |
Most recent IF: 1.455; 2012 IF: 1.545 |
| |
Call Number |
UA @ admin @ c:irua:99166 |
Serial |
5561 |
| Permanent link to this record |
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| |
|
Author |
De Trizio, L.; Figuerola, A.; Manna, L.; Genovese, A.; George, C.; Brescia, R.; Saghi, Z.; Simonutti, R.; van Huis, M.; Falqui, A. |
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Title |
Size-tunable, hexagonal plate-like Cu3P and Janus-like Cu-Cu3P nanocrystals |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
| |
Volume |
6 |
Issue |
1 |
Pages |
32-41 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| |
Abstract |
We describe two synthesis approaches to colloidal Cu3P nanocrystals using trioctylphosphine (TOP) as phosphorus precursor. One approach is based on the homogeneous nucleation of small Cu3P nanocrystals with hexagonal plate-like morphology and with sizes that can be tuned from 5 to 50 nm depending on the reaction time. In the other approach, metallic Cu nanocrystals are nucleated first and then they are progressively phosphorized to Cu3P. In this case, intermediate Janus-like dimeric nanoparticles can be isolated, which are made of two domains of different materials, Cu and Cu3P, sharing a flat epitaxial interface. The Janus-like nanoparticles can be transformed back to single-crystalline copper particles if they are annealed at high temperature under high vacuum conditions, which makes them an interesting source of phosphorus. The features of the Cu Cu3P Janus-like nanoparticles are compared with those of the Wiped microstructure discovered more than two decades ago in the rapidly quenched Cu Cu3P eutectic of the Cu P alloy, suggesting that other alloy/eutectic systems that display similar behavior might give origin to nanostructures with flat, epitaxial Interface between domains of two diverse materials. Finally, the electrochemical properties of the copper phosphide plates are studied, and they are found to be capable of undergoing lithiation/delithiation through a displacement reaction, while the Janus-like Cu Cu3P particles do not display an electrochemical behavior that would make them suitable for applications in batteries. |
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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 |
|
Editor |
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Language |
|
Wos |
000299368300006 |
Publication Date |
2011-12-03 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
13.942 |
Times cited |
60 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 13.942; 2012 IF: 12.062 |
| |
Call Number |
UA @ lucian @ c:irua:99172 |
Serial |
3039 |
| Permanent link to this record |
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|
| |
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Author |
Gardner, G.P.; Go, Y.B.; Robinson, D.M.; Smith, P.F.; Hadermann, J.; Abakumov, A.; Greenblatt, M.; Dismukes, G.C. |
| |
Title |
Structural requirements in lithium cobalt oxides for the catalytic oxidation of water |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Angewandte Chemie: international edition in English |
Abbreviated Journal |
Angew Chem Int Edit |
| |
Volume |
51 |
Issue |
7 |
Pages |
1616-1619 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
|
| |
Address |
|
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Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
| |
Language |
|
Wos |
000299946400020 |
Publication Date |
2012-01-11 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1433-7851; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
11.994 |
Times cited |
119 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 11.994; 2012 IF: 13.734 |
| |
Call Number |
UA @ lucian @ c:irua:99173 |
Serial |
3258 |
| Permanent link to this record |
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Author |
Kovba, M.L.; Skolis, Y.Y.; Abakumov, A.M.; Hadermann, J.; Sukhushina, I.S. |
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Title |
The synthesis and thermodynamic properties of strontium fluoromanganite Sr2.5Mn6O12.5-\deltaF2 |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Russian journal of physical chemistry A |
Abbreviated Journal |
Russ J Phys Chem A+ |
| |
Volume |
84 |
Issue |
12 |
Pages |
2033-2038 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
The existence of the [SrF(0.8)O(0.1)](2.5)[Mn(6)O(12)] = Sr(2.5)Mn(6)O(12.5 – delta)F(2) compound was established in the SrO-Mn(2)O(3)-SrF(2) system at 900A degrees C and p(O(2)) = 1 atm. The crystal structure of strontium fluoromanganite was determined from the X-ray powder diffraction data, electron diffraction, and high-resolution electron microscopy. It can be described in the monoclynic system with four Miller hklm indices: hklm: H = h a* + k b* + l c (1) (*) + m q (1), q (1), q (1) = c (2) (*) = gamma c (1) (*) , gamma a parts per thousand 0.632, a a parts per thousand a a parts per thousand 9.72 , b a parts per thousand 9.55 , c (1) a parts per thousand 2.84 , c (2) a parts per thousand 4.49 , monoclinic angle gamma a parts per thousand 95.6A degrees. The electromotive force method with a solid fluorine ion electrolyte was used to refine the composition of fluoromanganite and determine the thermodynamic functions of its formation from phases neighboring in the phase diagram (SrMn(3)O(6), Mn(2)O(3), SrF(2), and oxygen), Delta GA degrees, kJ/mol = -(111.7 +/- 1.9) + (89.5 +/- 1.5) x 10(-3) T. |
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Address |
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Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
London |
Editor |
|
| |
Language |
|
Wos |
000284775000004 |
Publication Date |
2011-02-11 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0036-0244;1531-863X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
0.581 |
Times cited |
1 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 0.581; 2010 IF: 0.503 |
| |
Call Number |
UA @ lucian @ c:irua:99190 |
Serial |
3601 |
| Permanent link to this record |
| |
|
| |
|
Author |
Quintana, M.; Ke, X.; Van Tendeloo, G.; Meneghetti, M.; Bittencourt, C.; Prato, M. |
| |
Title |
Light-induced selective deposition of Au nanoparticles on single-wall carbon nanotubes |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
| |
Volume |
4 |
Issue |
10 |
Pages |
6105-6113 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Novel applications of single-walled carbon nanotubes (SWNT) rely on the development of new strategies to make them easier to handle without affecting their structural properties. In this work, we have selectively deposited Au nanoparticles (Au NP) on SWNT assisted by UV light irradiation. XPS analysis and UV-vis spectroscopy indicate that the deposition occurs at the defects generated after oxidation of the SWNT. By addition of n-dodecylthiol, the separation of oxidized tubes with Au NP (Au-ox-SWNT) from tubes devoid of Au NP (bare tubes, b-SWNT) was achieved. Raman and UV-vis-NIR spectra indicate that UV irradiation induces a faster nucleation of Au NP on metallic SWNT. This new technique can be useful for the preparation of nanohybrid composites with enhanced properties, as increased thermal stability, and to obtain purified SWNT. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000283453700081 |
Publication Date |
2010-09-24 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
13.942 |
Times cited |
26 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 13.942; 2010 IF: 9.865 |
| |
Call Number |
UA @ lucian @ c:irua:99202 |
Serial |
1819 |
| Permanent link to this record |
| |
|
| |
|
Author |
Dong, H.M.; Xu, W.; Zhang, J.; Peeters, F.M.; Vasilopoulos, P. |
| |
Title |
Photo-excited carriers and optical conductance and transmission in graphene in the presence of phonon scattering |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Physica. E: Low-dimensional systems and nanostructures |
Abbreviated Journal |
Physica E |
| |
Volume |
42 |
Issue |
4 |
Pages |
748-750 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| |
Abstract |
We present a theoretical study of the optoelectronic properties of monolayer graphene. Including the effect of the electron-photon-phonon scattering, we employ the mass- and energy-balance equations derived from the Boltzmann equation to evaluate self-consistently the carrier densities, optical conductance and transmission coefficient in graphene in the presence of linearly polarized radiation field. We find that the photo-excited carrier density can be increased under infrared radiation and depend strongly on radiation intensity and frequency. For short wavelengths (lambda <3 mu m), the universal optical conductance sigma(0) = e(2)/4h is obtained and the light transmittance is about 0.97-0.98. Interestingly, there is an optical absorption window in the range 4-100 mu m which is induced by different transition energies required for inter- and intra-band optical absorption. The position and width of this absorption window depend sensitively on temperature and carrier density of the system. These results are relevant for applications of recently developed graphene devices in advanced optoelectronics such as the infrared photodetectors. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
North-Holland |
Place of Publication |
Amsterdam |
Editor |
|
| |
Language |
|
Wos |
000276541200022 |
Publication Date |
2009-11-25 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1386-9477; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.221 |
Times cited |
7 |
Open Access |
|
| |
Notes |
; ; |
Approved |
Most recent IF: 2.221; 2010 IF: 1.304 |
| |
Call Number |
UA @ lucian @ c:irua:99216 |
Serial |
2607 |
| Permanent link to this record |
| |
|
| |
|
Author |
Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M. |
| |
Title |
Tuning the superconducting properties of nanomaterials |
Type |
H1 Book chapter |
| |
Year |
2009 |
Publication |
|
Abbreviated Journal |
|
| |
Volume |
|
Issue |
|
Pages |
1-14 |
| |
Keywords |
H1 Book chapter; Condensed Matter Theory (CMT); Electron microscopy for materials research (EMAT) |
| |
Abstract |
Electron continement and its effect on the superconducting-to-normal phase transition driven by a magentic field and/or a current is studied in nanowires. Our investigation is based on a self-consistent numerical solution of the Bogoliubov-de Gennes equations. We find that in a parallel magneitc field and/or in the presence of a supercurrent the transition from the superconducting to the normal phase occurs as a cascade of discontinuous jumps in the superconducting order parameter for diameters D < 10 divided by 15 nm at T = 0. The critical magentic field exhibits quantum-size oscillations with pronounced resonant enhancements as a function of the wire radius. |
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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
Springer |
Place of Publication |
Dordrecht |
Editor |
|
| |
Language |
|
Wos |
000274282900001 |
Publication Date |
2009-07-29 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1874-6500; |
ISBN |
978-90-481-3118-1 |
Additional Links |
UA library record; WoS full record |
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: NA |
| |
Call Number |
UA @ lucian @ c:irua:99226 |
Serial |
3761 |
| Permanent link to this record |
| |
|
| |
|
Author |
Doria, M.M.; de Romaguera, A.R.C.; Milošević, M.V.; Peeters, F.M. |
| |
Title |
Domain coexistence of magnetism and superconductivity : appearance of confined vortex loops |
Type |
P1 Proceeding |
| |
Year |
2008 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
|
| |
Volume |
97 |
Issue |
|
Pages |
012070-012070,4 |
| |
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
| |
Abstract |
A magnetic moment inside an extreme type II superconductor can have three, but not one or two, confined vortex loops near to the core. For a sub-micron superconducting particle the confined vortex loops eventually break up and reach the surface turning into external vortex pairs. |
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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
| |
Language |
|
Wos |
000276054100070 |
Publication Date |
2008-03-20 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1742-6596; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| |
Impact Factor |
|
Times cited |
|
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: NA |
| |
Call Number |
UA @ lucian @ c:irua:99232 |
Serial |
747 |
| Permanent link to this record |
| |
|
| |
|
Author |
Baelus, B.J.; Kanda, A.; Peeters, F.M.; Ootuka, Y.; Kadowaki, K. |
| |
Title |
Giant and multivortex states in mesoscopic superconducting disks |
Type |
A1 Journal article |
| |
Year |
2005 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
| |
Volume |
426 |
Issue |
1 |
Pages |
132-135 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Transitions between different multivortex states and transitions between multivortex states and giant vortex states are observed in mesoscopic superconducting disks using the multiple-small-tunnel-junction method. These results are compared to theoretical calculations within the framework of the nonlinear Ginzburg-Landau theory. We find a good qualitative agreement between the theoretical and experimental results, when we assume that a small defect is present near the center of the experimental sample. (c) 2005 Elsevier B.V. All rights reserved. |
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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| |
Language |
|
Wos |
000232698500029 |
Publication Date |
2005-06-28 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| |
Impact Factor |
1.404 |
Times cited |
|
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 1.404; 2005 IF: 0.948 |
| |
Call Number |
UA @ lucian @ c:irua:99281 |
Serial |
1336 |
| Permanent link to this record |
| |
|
| |
|
Author |
Papp, G.; Peeters, F.M. |
| |
Title |
Magneto conductance for tunnelling through double magnetic barriers |
Type |
A1 Journal article |
| |
Year |
2005 |
Publication |
Physica. E: Low-dimensional systems and nanostructures |
Abbreviated Journal |
Physica E |
| |
Volume |
25 |
Issue |
4 |
Pages |
339-346 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| |
Abstract |
The temperature-dependent magnetoresistance effect is investigated in a magnetically modulated two-dimensional (21)) electron gas (2DEG) which can be realized by depositing two parallel ferromagnets on top of a 2DEG electron gas. In the resonant tunnelling regime the transmission for the parallel and antiparallel magnetization configurations shows a quite distinct dependence on the longitudinal wave vector of the incident electrons. This leads to a very large magneto resistance ratio with a strong temperature dependence. (C) 2004 Elsevier B.V. All rights reserved. |
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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
North-Holland |
Place of Publication |
Amsterdam |
Editor |
|
| |
Language |
|
Wos |
000226187900002 |
Publication Date |
2004-09-30 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
1386-9477; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.221 |
Times cited |
25 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 2.221; 2005 IF: 0.946 |
| |
Call Number |
UA @ lucian @ c:irua:99308 |
Serial |
1898 |
| Permanent link to this record |
| |
|
| |
|
Author |
Tadić, M.; Peeters, F.M. |
| |
Title |
Exciton states and oscillator strength in two vertically coupled InP/InGaP quantum discs |
Type |
A1 Journal article |
| |
Year |
2004 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
| |
Volume |
16 |
Issue |
47 |
Pages |
8633-8652 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Quantum mechanical coupling and strain in two vertically arranged InP/InGaP quantum dots is studied as a function of the size of the dots and the spacer thickness. The strain distribution is determined by the continuum mechanical model, while the single-band effective-mass equation and the multiband k (.) p theory are employed to compute the conduction and valence band energy levels, respectively. The exciton states are obtained from an exact diagonalization approach, and we also compute the oscillator strength for recombination. We found that the light holes are confined by strain to the spacer, which is the reason that the hole states exhibit coupling at much larger distances as compared with the electrons. At small d, the doublet structure of the hole energy levels arises as a consequence of the relocation of the light hole from the matrix to the regions located-outside the stack, close to the dot-matrix interface. When d varies, the exciton ground state exhibits numerous anticrossings with other states, which are related to the changing spatial localization of the hole as a function of d. The oscillator strength of the exciton recombination is strongly reduced in a certain range of spacer thicknesses, which effectively turns a bright exciton state into a dark one. This effect is associated with anticrossings between exciton energy levels. |
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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
London |
Editor |
|
| |
Language |
|
Wos |
000225796800016 |
Publication Date |
2004-11-13 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
2.649 |
Times cited |
13 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 2.649; 2004 IF: 2.049 |
| |
Call Number |
UA @ lucian @ c:irua:99315 |
Serial |
1116 |
| Permanent link to this record |
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|
| |
|
Author |
Anisimovas, E.; Peeters, F.M. |
| |
Title |
Dynamic response of artificial bipolar molecules |
Type |
A1 Journal article |
| |
Year |
2002 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
66 |
Issue |
7 |
Pages |
075311 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
We calculate the equilibrium properties and the dynamic response of two vertically coupled circular quantum dots populated by particles of different electrical charge sign, i.e., electrons and holes. The equilibrium density profiles are obtained and used to compute the frequencies and oscillator strengths of magnetoplasma excitations. We find a strong coupling between the modes derived from the center-of-mass modes of the individual dots which leads to an anticrossing with a pronounced oscillator strength transfer from the “acoustic” to the “optical” branch. Also, due to the breaking of the generalized Kohn theorem a number of other than center-of-mass modes are excited whose oscillator strengths, however, are rather weak. |
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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000177969800103 |
Publication Date |
2002-10-01 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.836 |
Times cited |
9 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 3.836; 2002 IF: NA |
| |
Call Number |
UA @ lucian @ c:irua:99397 |
Serial |
765 |
| Permanent link to this record |
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|
| |
|
Author |
Peeters, F.M.; Schweigert, V.A.; Baelus, B.J. |
| |
Title |
Fractional and negative flux penetration in mesoscopic superconducting disks |
Type |
A1 Journal article |
| |
Year |
2002 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
| |
Volume |
369 |
Issue |
1-4 |
Pages |
158-164 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The one vortex entry in a superconducting disk is investigated within the non-linear Ginzburg-Landau theory near the first critical field. We find that in mesoscopic superconducting disks the magnetic flux enters with fractions of one flux quantum phi(0) = ch/2e. For disks with a very smooth surface it is possible to drive the Meissner state so far into the metastable region that at the vortex entry a net amount of flux is expelled from the superconductor. We show that the magnetic field for flux entry is very sensitive to indentations of the disk surface and only weakly to bulges. On the other hand the flux exit field is practically insensitive to such geometrical surface defects. Our results are in agreement with recent experimental findings. (C) 2001 Elsevier Science B.V. All rights reserved. |
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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| |
Language |
|
Wos |
000174200000023 |
Publication Date |
2002-07-25 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
1.404 |
Times cited |
11 |
Open Access |
|
| |
Notes |
|
Approved |
Most recent IF: 1.404; 2002 IF: 0.912 |
| |
Call Number |
UA @ lucian @ c:irua:99412 |
Serial |
1272 |
| Permanent link to this record |
