| |
Records |
Links |
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Author |
Kishore, V.V.R.; Partoens, B.; Peeters, F.M. |
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| |
Title |
Electronic structure of InAs/GaSb core-shell nanowires |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
86 |
Issue |
16 |
Pages |
165439-7 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The electronic and optical properties of InAs/GaSb core-shell nanowires are investigated within the effective mass k . p approach. These systems have a broken band gap, which results in spatially separated confinement of electrons and holes. We investigated these structures for different sizes of the InAs and GaSb core and shell radius. We found that for certain configurations, the conduction band states penetrate into the valence band states resulting in a negative band gap (E-g < 0), which leads to a conduction band ground state that lies below the valence band ground state at the Gamma point. For certain core-shell wires, only one conduction band state penetrates into the valence band and in this case, a minigap Delta opens up away from the Gamma point and as a consequence the electronic properties of the nanowire now depend on both E-g and Delta values. |
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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 |
000310131400005 |
Publication Date |
2012-10-23 |
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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 |
|
Edition |
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| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.836 |
Times cited |
26 |
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:102164 |
Serial |
1014 |
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| Permanent link to this record |
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| |
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Author |
Lobato, I.; van Dyck, D. |
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| |
Title |
Improved multislice calculations for including higher-order Laue zones effects |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
|
| |
Volume |
119 |
Issue |
|
Pages |
63-71 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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| |
Abstract |
A new method for including higher-order Laue zones (HOLZs) effects in an efficient way in electron scattering simulations has been developed and tested by detail calculations. The calculated results by the conventional multislice (CMS) method and the improved conventional multislice (ICMS) method using a large dynamical aperture to avoid numerical errors are compared with accurate results. We have found that the zero-order Laue zones (ZOLZs) reflection cannot be properly described only using the projected potential in the whole unit cell; in general, we need to subslice the electrostatic potential inside the unit cell. It is shown that the ICMS method has higher accuracy than the CMS method for the calculation of the ZOLZ, HOLZ and Pseudo-HOLZ reflections. Hence, ICMS method allows to use a larger slice thickness than the CMS method and reduces the calculation time. (C) 2012 Elsevier B.V. All rights reserved. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000308079200011 |
Publication Date |
2012-01-14 |
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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 |
0304-3991; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.843 |
Times cited |
6 |
Open Access |
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| |
Notes |
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Approved |
Most recent IF: 2.843; 2012 IF: 2.470 |
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| |
Call Number |
UA @ lucian @ c:irua:101902 |
Serial |
1567 |
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| Permanent link to this record |
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| |
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Author |
Grzelczak, M.; Sánchez-Iglesias, A.; Heidari Mezerji, H.; Bals, S.; Pérez-Juste, J.; Liz-Marzán, L.M. |
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| |
Title |
Steric hindrance induces crosslike self-assembly of gold nanodumbbells |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
|
| |
Volume |
12 |
Issue |
8 |
Pages |
4380-4384 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
In the formation of colloidal molecules, directional interactions are crucial for controlling the spatial distribution of the building blocks. Anisotropic nanoparticles facilitate directional clustering via steric constraints imposed by each specific shape, thereby restricting assembly along certain directions. We show in this Letter that the combination of patchiness (attraction) and shape (steric hindrance) allows assembling gold nanodumbbell building blocks into crosslike dimers with well-controlled interparticle distance and relative orientation. Steric hindrance between interacting dumbbell-like particles opens up a new synthetic approach toward low-symmetry plasmonic clusters, which may significantly contribute to understand complex plasmonic phenomena. |
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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 |
Editor |
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| |
Language |
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Wos |
000307211000081 |
Publication Date |
2012-07-05 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
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| |
ISSN |
1530-6984;1530-6992; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
12.712 |
Times cited |
85 |
Open Access |
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| |
Notes |
Nanodirect 213948-2; 262348 Esmi |
Approved |
Most recent IF: 12.712; 2012 IF: 13.025 |
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| |
Call Number |
UA @ lucian @ c:irua:101900 |
Serial |
3161 |
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| Permanent link to this record |
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Author |
Peelaers, H.; Partoens, B.; Peeters, F.M. |
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Title |
Free-standing Si and Ge, and Ge/Si core-shell semiconductor nanowires |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Acta physica Polonica: A: general physics, solid state physics, applied physics
T2 – WELCOME Scientific Meeting on Hybrid Nanostructures, AUG 28-31, 2011, Torun, POLAND |
Abbreviated Journal |
Acta Phys Pol A |
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| |
Volume |
122 |
Issue |
2 |
Pages |
294-298 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The properties of free-standing silicon and germanium nanowires oriented along the [110] direction are studied using different first principles methods. We show the corrections due to quasi-particles to the band structures obtained using the local-density approximation. The formation energies of B and P doped nanowires are calculated, both in the absence and presence of dangling bond defects and we link these to experimental results. Furthermore, we report on the phonon properties of pure Si and Ge nanowires, as well as Ge/Si core-shell nanowires, and discuss the differences between them. |
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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 |
Warszawa |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
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Series Issue |
|
Edition |
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| |
ISSN |
0587-4246 |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
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| |
Impact Factor |
0.469 |
Times cited |
|
Open Access |
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| |
Notes |
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Approved |
Most recent IF: 0.469; 2012 IF: 0.531 |
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| |
Call Number |
UA @ lucian @ c:irua:101896 |
Serial |
1277 |
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| Permanent link to this record |
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Author |
Tsirlin, A.A.; Abakumov, A.M.; Ritter, C.; Rosner, H. |
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Title |
(CuCl)LaTa2O\text{7} and quantum phase transition in the (CuX)LaM2O7 family (X=Cl, Br; M=Nb, Ta) |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
86 |
Issue |
6 |
Pages |
064440-12 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We apply neutron diffraction, high-resolution synchrotron x-ray diffraction, magnetization measurements, electronic structure calculations, and quantum Monte-Carlo simulations to unravel the structure and magnetism of (CuCl)LaTa2O7. Despite the pseudo-tetragonal crystallographic unit cell, this compound features an orthorhombic superstructure, similar to the Nb-containing (CuX)LaNb2O7 with X = Cl and Br. The spin lattice entails dimers formed by the antiferromagnetic fourth-neighbor coupling J(4), as well as a large number of nonequivalent interdimer couplings quantified by an effective exchange parameter J(eff). In (CuCl)LaTa2O7, the interdimer couplings are sufficiently strong to induce the long-range magnetic order with the Neel temperature T-N similar or equal to 7 K and the ordered magnetic moment of 0.53 mu(B), as measured with neutron diffraction. This magnetic behavior can be accounted for by J(eff)/J(4) similar or equal to 1.6 and J(4) similar or equal to 16 K. We further propose a general magnetic phase diagram for the (CuCl)LaNb2O7-type compounds, and explain the transition from the gapped spin-singlet (dimer) ground state in (CuCl)LaNb2O7 to the long-range antiferromagnetic order in (CuCl)LaTa2O7 and (CuBr)LaNb2O7 by an increase in the magnitude of the interdimer couplings J(eff)/J(4), with the (CuCl)LaM2O7 (M = Nb, Ta) compounds lying on different sides of the quantum critical point that separates the singlet and long-range-ordered magnetic ground states. |
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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 |
000308127600006 |
Publication Date |
2012-08-29 |
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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 |
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| |
Impact Factor |
3.836 |
Times cited |
6 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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| |
Call Number |
UA @ lucian @ c:irua:101886 |
Serial |
3526 |
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| Permanent link to this record |
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Author |
Lin, N.S.; Misko, V.R.; Heitmann, T.W.; Yu, K.; Plourde, B.L.T. |
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Title |
Density dependence of the rectification of vortex motion in a circular asymmetric channel |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
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| |
Volume |
479 |
Issue |
|
Pages |
137-139 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We study the rectification of vortex motion in an asymmetric ring channel in a Corbino setup. With an applied ac current, the motion of vortices in the channel is rectified by the asymmetric potential and induces a dc net flow. The net flow in such a system strongly depends on vortex density, and we distinguish “single-vortex'' rectification regime (for low density, when each vortex is rectified individually) determined by the potential-energy landscape inside each cell of the channel and ”multi-vortex'', or "collective'', rectification (high density case) when the interaction between vortices becomes important. (C) 2012 Elsevier B.V. All rights reserved. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000308580600032 |
Publication Date |
2012-01-06 |
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Series Editor |
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Series Title |
|
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 |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
1.404 |
Times cited |
|
Open Access |
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Notes |
; This work was supported by the "Odysseus'' Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl), the Interuniversity Attraction Poles (IAP) Programme – Belgian State – Belgian Science Policy, and the FWO-Vl (Belgium). ; |
Approved |
Most recent IF: 1.404; 2012 IF: 0.718 |
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Call Number |
UA @ lucian @ c:irua:101873 |
Serial |
635 |
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| Permanent link to this record |
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Author |
Zhao, H.J.; Misko, V.R.; Peeters, F.M. |
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Title |
Vortex configurations with non-monotonic interaction |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
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Volume |
479 |
Issue |
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Pages |
130-133 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The pattern formation of the vortex states with non-monotonic inter-vortex interaction is investigated. Our applied model has a short-range repulsive (r < r(c)) and long-range attractive (r > r(c)) potential. We numerically calculate the stable states using molecular-dynamics simulations. The obtained vortex patterns are comparable with the vortices states in low kappa type-II superconductors and recently discovered "type-1.5'' superconductors. We also analyze the nearest neighbor distribution of the obtained patterns. (C) 2012 Published by Elsevier B.V. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000308580600030 |
Publication Date |
2012-01-06 |
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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 |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.404 |
Times cited |
9 |
Open Access |
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Notes |
; We acknowledge fruitful discussions with Ernst Helmut Brandt. This work was supported by the "Odysseus'' Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl), the IAP and FWO-Vl. ; |
Approved |
Most recent IF: 1.404; 2012 IF: 0.718 |
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Call Number |
UA @ lucian @ c:irua:101872 |
Serial |
3864 |
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| Permanent link to this record |
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Author |
Komendová, L.; Shanenko, A.A.; Milošević, M.V.; Peeters, F.M. |
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Title |
The healing lengths in two-band superconductors in extended Ginzburg-Landau theory |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
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| |
Volume |
479 |
Issue |
|
Pages |
126-129 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We study the vortex profiles in two-gap superconductors using the extended Ginzburg-Landau theory. The results shed more light on the disparity between the effective length scales in two bands. We compare the behavior expected from the standard Ginzburg-Landau theory with this new approach, and find good qualitative agreement in the case of LiFeAs. (C) 2011 Elsevier B.V. All rights reserved. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
000308580600029 |
Publication Date |
2012-01-04 |
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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 |
0921-4534; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.404 |
Times cited |
1 |
Open Access |
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| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-INSTANS network. ; |
Approved |
Most recent IF: 1.404; 2012 IF: 0.718 |
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Call Number |
UA @ lucian @ c:irua:101871 |
Serial |
3585 |
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| Permanent link to this record |
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Author |
de Aquino, B.R.C.H.T.; Cabral, L.R.E.; de Souza Silva, C.C.; Albino Aguiar, J.; Milošević, M.V.; Peeters, F.M. |
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Title |
Dynamic phases of vortex-antivortex molecules in a Corbino disk with magnetic dipole on top |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
|
| |
Volume |
479 |
Issue |
|
Pages |
115-118 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We performed a molecular dynamics study of vortex-antivortex motion in a superconducting disk with a magnetic dot on top, in the Corbino disk geometry. In this system, vortices and antivortices are forced to move in opposite azimuthal directions by a radially applied current. The dot is magnetized out of plane in order to stabilize composite vortex-antivortex configurations, with vortices closer to the center of the disk and antivortices near to the disk edge. We observe that the interplay between the spatially inhomogeneous current distribution, the screening currents induced by the dipole, and the attractive vortex-antivortex (v-av) interaction result in different dynamical phases. At low current values, antivortices which are distributed at outer rings – remain bounded to vortices at inner rings and the whole configuration rotates rigidly. Above a threshold current, vortices and antivortices unbind and move at different angular velocities in a highly correlated way. Finally, at very strong drive, vortex-antivortex attraction is overhelmed by the external current Lorentz force, causing them to move in opposite directions. (C) 2011 Elsevier B.V. All rights reserved. |
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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 |
Amsterdam |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
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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 |
0921-4534 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
1.404 |
Times cited |
|
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 1.404; 2012 IF: 0.718 |
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| |
Call Number |
UA @ lucian @ c:irua:101870 |
Serial |
764 |
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| Permanent link to this record |
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Author |
Zhang, L.-F.; Covaci, L.; Milošević, M.V.; Berdiyorov, G.R.; Peeters, F.M. |
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Title |
Unconventional vortex states in nanoscale superconductors due to shape-induced resonances in the inhomogeneous Cooper-pair condensate |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
|
| |
Volume |
109 |
Issue |
10 |
Pages |
107001 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Vortex matter in mesoscopic superconductors is known to be strongly affected by the geometry of the sample. Here we show that in nanoscale superconductors with coherence length comparable to the Fermi wavelength the shape resonances of the order parameter results in an additional contribution to the quantum topological confinement-leading to unconventional vortex configurations. Our Bogoliubov-de Gennes calculations in a square geometry reveal a plethora of asymmetric, giant multivortex, and vortex-antivortex structures, stable over a wide range of parameters and which are very different from those predicted by the Ginzburg-Landau theory. These unconventional states are relevant for high-T-c nanograins, confined Bose-Einstein condensates, and graphene flakes with proximity-induced superconductivity. |
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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 |
000308295700014 |
Publication Date |
2012-09-05 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
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| |
ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
8.462 |
Times cited |
31 |
Open Access |
|
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| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen). ; |
Approved |
Most recent IF: 8.462; 2012 IF: 7.943 |
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| |
Call Number |
UA @ lucian @ c:irua:101850 |
Serial |
3801 |
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| Permanent link to this record |
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Author |
Szumniak, P.; Bednarek, S.; Partoens, B.; Peeters, F.M. |
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Title |
Spin-orbit-mediated manipulation of heavy-hole spin qubits in gated semiconductor nanodevices |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
|
| |
Volume |
109 |
Issue |
10 |
Pages |
107201 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
A novel spintronic nanodevice is proposed that is able to manipulate the single heavy-hole spin state in a coherent manner. It can act as a single quantum logic gate. The heavy-hole spin transformations are realized by transporting the hole around closed loops defined by metal gates deposited on top of the nanodevice. The device exploits Dresselhaus spin-orbit interaction, which translates the spatial motion of the hole into a rotation of the spin. The proposed quantum gate operates on subnanosecond time scales and requires only the application of a weak static voltage which allows for addressing heavy-hole spin qubits individually. Our results are supported by quantum mechanical time-dependent calculations within the four-band Luttinger-Kohn model. |
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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 |
000308295700015 |
Publication Date |
2012-09-05 |
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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 |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
8.462 |
Times cited |
41 |
Open Access |
|
|
| |
Notes |
; This work was supported by the Grant No. NN202 128337 from the Ministry of Science and Higher Education, as well as by the “Krakow Interdisciplinary PhD-Project in Nanoscience and Advances Nanostructures” operated within the Foundation for Polish Science MPD Programme and cofinanced by European Regional Development Fund, the Belgian Science Policy (IAP), and the Flemish Science Foundation (FWO-V1). ; |
Approved |
Most recent IF: 8.462; 2012 IF: 7.943 |
|
| |
Call Number |
UA @ lucian @ c:irua:101849 |
Serial |
3094 |
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| Permanent link to this record |
| |
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| |
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Author |
Hadermann, J.; Abakumov, A.; Van Rompaey, S.; Perkisas, T.; Filinchuk, Y.; Van Tendeloo, G. |
|
| |
Title |
Crystal structure of a lightweight borohydride from submicrometer crystallites by precession electron diffraction |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
|
| |
Volume |
24 |
Issue |
17 |
Pages |
3401-3405 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
We demonstrate that precession electron diffraction at low-dose conditions can be successfully applied for structure analysis of extremely electron-beam-sensitive materials. Using LiBH4 as a test material, complete structural information, including the location of the H atoms, was obtained from submicrometer-sized crystallites. This demonstrates for the first time that, where conventional transmission electron microscopy techniques fail, quantitative precession electron diffraction can provide structural information from submicrometer particles of such extremely electron-beam-sensitive materials as complex lightweight hydrides. We expect the precession electron diffraction technique to be a useful tool for nanoscale investigations of thermally unstable lightweight hydrogen-storage materials. |
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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 |
|
Wos |
000308833400012 |
Publication Date |
2012-08-01 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
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 |
17 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
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| |
Call Number |
UA @ lucian @ c:irua:101845 |
Serial |
567 |
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| Permanent link to this record |
| |
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| |
|
Author |
Shanenko, A.A.; Croitoru, M.D.; Vagov, A.V.; Axt, V.M.; Perali, A.; Peeters, F.M. |
|
| |
Title |
Atypical BCS-BEC crossover induced by quantum-size effects |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : A : atomic, molecular and optical physics |
Abbreviated Journal |
Phys Rev A |
|
| |
Volume |
86 |
Issue |
3 |
Pages |
033612 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
Quantum-size oscillations of the basic physical characteristics of a confined fermionic condensate are a well-known phenomenon. Its conventional understanding is based on the single-particle physics, whereby the oscillations follow variations in the single-particle density of states driven by the size quantization. Here we present a study of a cigar-shaped ultracold superfluid Fermi gas, which demonstrates an important many-body aspect of the quantum-size coherent effects, overlooked previously. The many-body physics is revealed here in the atypical crossover from the Bardeen-Cooper-Schrieffer (BCS) superfluid to the Bose-Einstein condensate (BEC) induced by the size quantization of the particle motion. The single-particle energy spectrum for the transverse dimensions is tightly bound, whereas for the longitudinal direction it resembles a quasi-free dispersion. This results in the formation of a series of single-particle subbands (shells) so that the aggregate fermionic condensate becomes a coherent mixture of subband condensates. Each time when the lower edge of a subband crosses the chemical potential, the BCS-BEC crossover is approached in this subband, and the aggregate condensate contains both BCS and BEC-like components. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
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| |
Language |
|
Wos |
000308639500004 |
Publication Date |
2012-09-15 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1050-2947;1094-1622; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.925 |
Times cited |
34 |
Open Access |
|
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). The authors thank C. Salomon and C. Vale for their valuable explications of the experimental situation and interest to our work. We are grateful to G. C. Strinati, D. Neilson, and P. Pieri for useful discussions. M. D. C. acknowledges support of the EU Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR). A. P. gratefully acknowledges financial support of the European Science Foundation, POLATOM Research Networking Programme, Ref. No. 4844 for his visit to the University of Antwerp. A. A. S. acknowledges financial support of the European Science Foundation, POLATOM Research Networking Programme, Ref. No. 5200 for his visit to the University of Camerino. ; |
Approved |
Most recent IF: 2.925; 2012 IF: 3.042 |
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| |
Call Number |
UA @ lucian @ c:irua:101844 |
Serial |
203 |
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| Permanent link to this record |
| |
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| |
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Author |
Sivek, J.; Leenaerts, O.; Partoens, B.; Peeters, F.M. |
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| |
Title |
First-principles investigation of bilayer fluorographene |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
|
| |
Volume |
116 |
Issue |
36 |
Pages |
19240-19245 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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| |
Abstract |
Ab initio calculations within the density functional theory formalism are performed to investigate the stability and electronic properties of fluorinated bilayer graphene (bilayer fluorographene). A comparison is made to previously investigated graphane, bilayer graphane, and fluorographene. Bilayer fluorographene is found to be a much more stable material than bilayer graphane. Its electronic band structure is similar to that of monolayer fluorographene, but its electronic band gap is significantly larger (about 1 eV). We also calculate the effective masses around the Gamma-point for fluorographene and bilayer fluorographene and find that they are isotropic, in contrast to earlier reports. Furthermore, it is found that bilayer fluorographene is almost as strong as graphene, as its 2D Young's modulus is approximately 300 N m(-1). |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
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| |
Language |
|
Wos |
000308631300022 |
Publication Date |
2012-08-21 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
4.536 |
Times cited |
39 |
Open Access |
|
|
| |
Notes |
; This work is supported by the ESF-Eurocores program EuroGRAPHENE (project CONERAN) and the Flemish Science Foundation (FWO-V1). ; |
Approved |
Most recent IF: 4.536; 2012 IF: 4.814 |
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| |
Call Number |
UA @ lucian @ c:irua:101842 |
Serial |
1211 |
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| Permanent link to this record |
| |
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| |
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Author |
Gotter, R.; Fratesi, G.; Bartynski, R.A.; da Pieve, F.; Offi, F.; Ruocco, A.; Ugenti, S.; Trioni, M.I.; Brivio, G.P.; Stefani, G. |
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| |
Title |
Spin-dependent on-site electron correlations and localization in itinerant f erromagnets |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
|
| |
Volume |
109 |
Issue |
12 |
Pages |
126401 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Spin selectivity in angle-resolved Auger photoelectron coincidence spectroscopy (AR-APECS) is used to probe electron correlation in ferromagnetic thin films. In particular, exploiting the AR-APECS capability to discriminate Auger electron emission events characterized by valence hole pairs created either in the high or in the low total spin state, a strong correlation effect in the Fe M2,3VV Auger line shape (measured in coincidence with the Fe 3p photoelectrons) of Fe/Cu(001) thin films is detected and ascribed to interactions within the majority spin subband. Such an assignment follows from a close comparison of the experimental AR-APECS line shapes with the predictions of a model based on spin polarized density functional theory and the Cini-Sawatzky approach. |
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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 |
|
Wos |
000308877000002 |
Publication Date |
2012-09-21 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
8.462 |
Times cited |
9 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 8.462; 2012 IF: 7.943 |
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| |
Call Number |
UA @ lucian @ c:irua:101841 |
Serial |
3084 |
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| Permanent link to this record |
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| |
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Author |
Euán-Díaz, E.C.; Misko, V.R.; Peeters, F.M.; Herrera-Velarde, S.; Castaneda-Priego, R. |
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| |
Title |
Single-file diffusion in periodic energy landscapes : the role of hydrodynamic interactions |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : E : statistical, nonlinear, and soft matter physics |
Abbreviated Journal |
Phys Rev E |
|
| |
Volume |
86 |
Issue |
3Part 1 |
Pages |
031123 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
We report on the dynamical properties of interacting colloids confined to one dimension and subjected to external periodic energy landscapes. We particularly focus on the influence of hydrodynamic interactions on the mean-square displacement. Using Brownian dynamics simulations, we study colloidal systems with two types of repulsive interparticle interactions, namely, Yukawa and superparamagnetic potentials. We find that in the homogeneous case, hydrodynamic interactions lead to an enhancement of the particle mobility and the mean-square displacement at long times scales as t(alpha), with alpha = 1/2 + epsilon and epsilon being a small correction. This correction, however, becomes much more important in the presence of an external field, which breaks the homogeneity of the particle distribution along the line and, therefore, promotes a richer dynamical scenario due to the hydrodynamical coupling among particles. We provide here the complete dynamical scenario in terms of the external potential parameters: amplitude and commensurability. |
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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 |
000308873500002 |
Publication Date |
2012-09-21 |
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| |
Series Editor |
|
Series Title |
|
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 |
14 |
Open Access |
|
|
| |
Notes |
; This work was partially supported by the “Odysseus” Program of the Flemish Government, the Flemish Science Foundation (FWO-Vl), and PIFI 3.4-PROMEP and CONACyT (Grant Nos. 61418/2007 and 102339/2008, Ph.D. Scholarship No. 230171/ 2010). ; |
Approved |
Most recent IF: 2.366; 2012 IF: 2.313 |
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| |
Call Number |
UA @ lucian @ c:irua:101840 |
Serial |
3021 |
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| Permanent link to this record |
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| |
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Author |
Nowak, M.P.; Szafran, B.; Peeters, F.M. |
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| |
Title |
Resonant harmonic generation and collective spin rotations in electrically driven quantum dots |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
86 |
Issue |
12 |
Pages |
125428 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Spin rotations induced by an ac electric field in a two-electron double quantum dot are studied by an exact numerical solution of the time-dependent Schrodinger equation in the context of recent electric-dipole spin resonance experiments on gated nanowires. We demonstrate that the splitting of the main resonance line by the spin exchange coupling is accompanied by the appearance of fractional resonances and that both these effects are triggered by interdot tunnel coupling. We find that the ac-driven system generates residual but distinct harmonics of the driving frequency, which are amplified when tuned to the main transition frequency. The mechanism is universal for electron systems in electrically driven potentials and works also in the absence of electron-electron interaction or spin-orbit coupling. |
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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 |
000308867300005 |
Publication Date |
2012-09-21 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
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 |
29 |
Open Access |
|
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| |
Notes |
; This work was supported by funds of the Ministry of Science and Higher Education (MNiSW) for 2012-2013 under Project No. IP2011038671, and by PL-Grid Infrastructure. M.P.N. gratefully acknowledges support from the Foundation for Polish Science (FNP) under START and MPD program cofinanced by the EU European Regional Development Fund. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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| |
Call Number |
UA @ lucian @ c:irua:101839 |
Serial |
2885 |
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| Permanent link to this record |
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Author |
Sena, S.H.R.; Pereira, J.M.; Farias, G.A.; Peeters, F.M.; Costa Filho, R.N. |
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Title |
The electronic properties of graphene and graphene ribbons under simple shear strain |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
|
| |
Volume |
24 |
Issue |
37 |
Pages |
375301 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
A tight-binding model is used to study the energy band of graphene and graphene ribbon under simple shear strain. The ribbon consists of lines of carbon atoms in an armchair or zigzag orientation where a simple shear strain is applied in the x-direction keeping the atomic distances in the y-direction unchanged. Such modification in the lattice gives an energy band that differs in several aspects from the one without any shear and with pure shear. The changes in the spectrum depend on the line displacement of the ribbon, and also on the modified hopping parameter. It is also shown that this simple shear strain tunes the electronic properties of both graphene and graphene ribbon, opening and closing energy gaps for different displacements of the system. The modified density of states is also shown. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
London |
Editor |
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| |
Language |
|
Wos |
000308202700011 |
Publication Date |
2012-08-14 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.649 |
Times cited |
15 |
Open Access |
|
|
| |
Notes |
; This work was supported by CNPq (RNCF), the National Council for the Improvement of Higher Education (CAPES), the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the bilateral program between Flanders and Brazil. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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| |
Call Number |
UA @ lucian @ c:irua:101838 |
Serial |
1000 |
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| Permanent link to this record |
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Author |
Moldovan, D.; Masir, M.R.; Covaci, L.; Peeters, F.M. |
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| |
Title |
Resonant valley filtering of massive Dirac electrons |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
86 |
Issue |
11 |
Pages |
115431 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Electrons in graphene, in addition to their spin, have two pseudospin degrees of freedom: sublattice and valley pseudospin. Valleytronics uses the valley degree of freedom as a carrier of information similarly to the way spintronics uses electron spin. We show how a double-barrier structure consisting of electric and vector potentials can be used to filter massive Dirac electrons based on their valley index. We study the resonant transmission through a finite number of barriers and we obtain the energy spectrum of a superlattice consisting of electric and vector potentials. When a mass term is included, the energy bands and energy gaps at the K and K′ points are different and they can be tuned by changing the potential. |
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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 |
000309173300004 |
Publication Date |
2012-09-21 |
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| |
Series Editor |
|
Series Title |
|
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 |
55 |
Open Access |
|
|
| |
Notes |
This work was supported by the European Science Foundation (ESF) under the EUROCORES Program Euro- GRAPHENE within the project CONGRAN, and 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:101835 |
Serial |
2896 |
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| Permanent link to this record |
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Author |
Badalyan, S.M.; Peeters, F.M. |
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| |
Title |
Enhancement of Coulomb drag in double-layer graphene structures by plasmons and dielectric background inhomogeneity |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
86 |
Issue |
12 |
Pages |
121405 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
The drag of massless fermions in graphene double-layer structures is investigated over a wide range of temperatures and interlayer separations. We show that the inhomogeneity of the dielectric background in such graphene structures, for experimentally relevant parameters, results in a significant enhancement of the drag resistivity. At intermediate temperatures the dynamical screening via plasmon-mediated drag enhances the drag resistivity and results in an upturn in its behavior at large interlayer separations. In a range of interlayer separations, corresponding to the crossover from strong to weak coupling of graphene layers, we find that the decrease of the drag resistivity with interlayer spacing is approximately quadratic. This dependence weakens below this range of interlayer spacing while for larger separations we find a cubic (quartic) dependence at intermediate (low) temperatures. |
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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 |
000309178100003 |
Publication Date |
2012-09-21 |
|
| |
Series Editor |
|
Series Title |
|
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 |
21 |
Open Access |
|
|
| |
Notes |
; We acknowledge support from the Flemisch Science Foundation (FWO-Vl) and the Belgian Science Policy (BELSPO). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
|
| |
Call Number |
UA @ lucian @ c:irua:101834 |
Serial |
1060 |
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| Permanent link to this record |
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| |
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Author |
da Costa, D.R.; Chaves, A.; Farias, G.A.; Covaci, L.; Peeters, F.M. |
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| |
Title |
Wave-packet scattering on graphene edges in the presence of a pseudomagnetic field |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
86 |
Issue |
11 |
Pages |
115434 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The scattering of a Gaussian wave packet in armchair and zigzag graphene edges is theoretically investigated by numerically solving the time-dependent Schrodinger equation for the tight-binding model Hamiltonian. Our theory allows us to investigate scattering in reciprocal space, and depending on the type of graphene edge we observe scattering within the same valley, or between different valleys. In the presence of an external magnetic field, the well-known skipping orbits are observed. However, our results demonstrate that in the case of a pseudomagnetic field, induced by nonuniform strain, the scattering by an armchair edge results in a nonpropagating edge 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 |
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Editor |
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| |
Language |
|
Wos |
000309174100005 |
Publication Date |
2012-09-21 |
|
| |
Series Editor |
|
Series Title |
|
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 |
28 |
Open Access |
|
|
| |
Notes |
; Discussions with E. B. Barros are gratefully acknowledged. This work was supported by the Brazilian Council for Research (CNPq), the Flemish Science Foundation (FWO-Vl), the ESF-EuroGRAPHENE (project CONGRAN), and the bilateral program between Flanders and Brazil. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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| |
Call Number |
UA @ lucian @ c:irua:101833 |
Serial |
3907 |
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| Permanent link to this record |
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Author |
Vagov, A.; Shanenko, A.A.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. |
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| |
Title |
Two-band superconductors : extended Ginzburg-Landau formalism by a systematic expansion in small deviation from the critical temperature |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
| |
Volume |
86 |
Issue |
14 |
Pages |
144514 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
We derive the extended Ginzburg-Landau (GL) formalism for a clean s-wave two-band superconductor by employing a systematic expansion of the free-energy functional and the corresponding matrix gap equation in powers of the small deviation from the critical temperature tau = 1 – T/T-c. The two lowest orders of this expansion produce the equation for T-c and the standard GL theory. It is shown that in agreement with previous studies, this two-band GL theory maps onto the single-band GL model and thus fails to describe the difference in the spatial profiles of the two-band condensates. We prove that this difference appears already in the leading correction to the standard GL theory, which constitutes the extended GL formalism. We derive linear differential equations that determine the leading corrections to the band order parameters and magnetic field, discuss the validity of these equations, and consider examples of an important interplay between the band condensates. Finally, we present numerical results for the thermodynamic critical magnetic field and temperature-dependent band gaps for recent materials of interest, which are in very good agreement with those obtained from the full BCS approach in a wide temperature range. To this end, we emphasize the advantages of our extended GL theory in comparison with the often used two-component GL-like model based on an unreconstructed two-band generalization of the Gor'kov derivation. |
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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 |
000309776800001 |
Publication Date |
2012-10-12 |
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| |
Series Editor |
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Series Title |
|
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 |
44 |
Open Access |
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|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). Authors are indebted to Y. Singh and R. Prozorov for discussions and for providing recent experimental data. A. V. is grateful to W. Pesch for stimulating discussions and critical comments on this work. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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| |
Call Number |
UA @ lucian @ c:irua:101798 |
Serial |
3769 |
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| Permanent link to this record |
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| |
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Author |
Liu, J.; Jin, J.; Deng, Z.; Huang, S.Z.; Hu, Z.Y.; Wang, L.; Wang, C.; Chen, L.H.; Li, Y.; Van Tendeloo, G.; Su, B.L.; |
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| |
Title |
Tailoring CuO nanostructures for enhanced photocatalytic property |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of colloid and interface science |
Abbreviated Journal |
J Colloid Interf Sci |
|
| |
Volume |
384 |
Issue |
|
Pages |
1-9 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
We report on one-pot synthesis of various morphologies of CuO nanostructures. PEG200 as a structure directing reagent under the synergism of alkalinity by hydrothermal method has been employed to tailor the morphology of CuO nanostructures. The CuO products have been characterized by XRD, SEM, and TEM. The morphologies of the CuO nanostructures can be tuned from 10 (nanoseeds, nanoribbons) to 2D (nanoleaves) and to 3D (shuttle-like, shrimp-like, and nanoflowers) by changing the volume of PEG200 and the alkalinity in the reaction system. At neutral and relatively low alkalinity (OH-/Cu2+ <= 3), the addition of PEG200 can strongly influence the morphologies of the CuO nanostructures. At high alkalinity (OH/Cu2+ >= 4), PEG200 has no influence on the morphology of the CuO nanostructure. The different morphologies of the CuO nanostructures have been used for the photodecomposition of the pollutant rhodamine B (RhB) in water. The photocatalytic activity has been correlated with the different nanostructures of CuO. The 10 CuO nanoribbons exhibit the best performance on the RhB photodecomposition because of the exposed high surface energy {-121} crystal plane. The photocatalytic results show that the high energy surface planes of the CuO nanostructures mostly affect the photocatalytic activity rather than the morphology of the CuO nanostructures. Our synthesis method also shows it is possible to control the morphologies of nanostructures in a simple way. (C) 2012 Elsevier Inc. All rights reserved. |
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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 |
|
Wos |
000308337700001 |
Publication Date |
2012-06-27 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0021-9797; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
4.233 |
Times cited |
105 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 4.233; 2012 IF: 3.172 |
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| |
Call Number |
UA @ lucian @ c:irua:101796 |
Serial |
3468 |
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| Permanent link to this record |
| |
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| |
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Author |
Verheyen, E.; Joos, L.; Van Havenbergh, K.; Breynaert, E.; Kasian, N.; Gobechiya, E.; Houthoofd, K.; Martineau, C.; Hinterstein, M.; Taulelle, F.; Van Speybroeck, V.; Waroquier, M.; Bals, S.; Van Tendeloo, G.; Kirschhock, C.E.A.; Martens, J.A.; |
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| |
Title |
Design of zeolite by inverse sigma transformation |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Nature materials |
Abbreviated Journal |
Nat Mater |
|
| |
Volume |
11 |
Issue |
12 |
Pages |
1059-1064 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Although the search for new zeolites has traditionally been based on trial and error, more rational methods are now available. The theoretical concept of inverse transformation of a zeolite framework to generate a new structure by removal of a layer of framework atoms and contraction has for the first time been achieved experimentally. The reactivity of framework germanium atoms in strong mineral acid was exploited to selectively remove germanium-containing four-ring units from an UTL type germanosilicate zeolite. Annealing of the leached framework through calcination led to the new all-silica COK-14 zeolite with intersecting 12- and 10-membered ring channel systems. An intermediate stage of this inverse transformation with dislodged germanate four-rings still residing in the pores could be demonstrated. Inverse transformation involving elimination of germanium-containing structural units opens perspectives for the synthesis of many more zeolites. |
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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 |
Editor |
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| |
Language |
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Wos |
000311432600025 |
Publication Date |
2012-10-19 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1476-1122;1476-4660; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
39.737 |
Times cited |
140 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 39.737; 2012 IF: 35.749 |
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| |
Call Number |
UA @ lucian @ c:irua:101783 |
Serial |
661 |
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| Permanent link to this record |
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Author |
Saniz, R.; Xu, Y.; Matsubara, M.; Amini, M.N.; Dixit, H.; Lamoen, D.; Partoens, B. |
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| |
Title |
A simplified approach to the band gap correction of defect formation energies : Al, Ga, and In-doped ZnO |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
The journal of physics and chemistry of solids |
Abbreviated Journal |
J Phys Chem Solids |
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| |
Volume |
74 |
Issue |
1 |
Pages |
45-50 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
| |
Abstract |
The calculation of defect levels in semiconductors within a density functional theory approach suffers greatly from the band gap problem. We propose a band gap correction scheme that is based on the separation of energy differences in electron addition and relaxation energies. We show that it can predict defect levels with a reasonable accuracy, particularly in the case of defects with conduction band character, and yet is simple and computationally economical. We apply this method to ZnO doped with group III elements (Al, Ga, In). As expected from experiment, the results indicate that Zn substitutional doping is preferred over interstitial doping in Al, Ga, and In-doped ZnO, under both zinc-rich and oxygen-rich conditions. Further, all three dopants act as shallow donors, with the +1 charge state having the most advantageous formation energy. Also, doping effects on the electronic structure of ZnO are sufficiently mild so as to affect little the fundamental band gap and lowest conduction bands dispersion, which secures their n-type transparent conducting behavior. A comparison with the extrapolation method based on LDA+U calculations and with the HeydScuseriaErnzerhof hybrid functional (HSE) shows the reliability of the proposed scheme in predicting the thermodynamic transition levels in shallow donor systems. |
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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 |
000311062500009 |
Publication Date |
2012-08-10 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
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Edition |
|
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| |
ISSN |
0022-3697; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.059 |
Times cited |
36 |
Open Access |
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| |
Notes |
Fwo; Bof-Nio |
Approved |
Most recent IF: 2.059; 2013 IF: 1.594 |
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| |
Call Number |
UA @ lucian @ c:irua:101782 |
Serial |
3004 |
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| Permanent link to this record |
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Author |
Sánchez-Muñoz, L.; García-Guinea, J.; Zagorsky, V.Y.; Juwono, T.; Modreski, P.J.; Cremades, A.; Van Tendeloo, G.; de Moura, O.J.M. |
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Title |
The evolution of twin patterns in perthitic K-feldspar from garnitic pegmatites |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Canadian mineralogist |
Abbreviated Journal |
Can Mineral |
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| |
Volume |
50 |
Issue |
4 |
Pages |
989-1024 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Grains of K-feldspar are commonly seen as heterogeneous mixtures of mineral species and varieties with random microstructures. Most consider that observable features arise from incomplete re-equilibrations owing to slow kinetic and localized effects of aqueous fluids (catalyst), with geological environment and chemical impurities playing only a secondary role. Here, an alternative approach is explored by studying well-preserved regularities in the twin patterns of K-feldspars formed in the subsolidus stage from a historical perspective. Selected samples from granitic pegmatites were studied by polarized light optical microscopy (PLOM), electron-probe micro-analysis (EPMA), scanning (SEM) and transmission electron microscopy (TEM), cathodoluminescence imaging (CL), micro-Raman spectroscopy (MRS) and 31P nuclear magnetic resonance (NMR). We have found that the essential feature of this crystalline medium is the astounding capability to recrystallize in self-organized twin patterns. The mechanism involves coupling between short-range atomic motion, and long-range displacive correlations propagated as ideal and non-ideal Albite and Pericline orientations. We suggest a general evolutionary process to explain the development of macroscopic twin patterns in microcline, based on three twin generations as microtwins, macrotwins and cryptotwins. Evolutionary variants also were identified; they depend on both internal crystallochemical features and an external geological stimulus. We suggest a continuous monoclinictriclinic transformation for impure K-feldspar, whereas a discontinuous inversion occurs where the starting composition is close to the ideal chemical formula. Twin patterns can evolve by twin coarsening to single-orientation microcline if the system releases energy, or by twin fragmentation to finely twinned microcline if the system stores energy. Hence, K-feldspar is seen here as a very sensitive medium in which precious geological information is recorded in the form of twin patterns, and thus useful for general geological challenges. |
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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 |
Toronto |
Editor |
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Language |
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Wos |
000314174400015 |
Publication Date |
2012-10-29 |
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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 |
0008-4476;1499-1276; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
0.817 |
Times cited |
11 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 0.817; 2012 IF: 1.180 |
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| |
Call Number |
UA @ lucian @ c:irua:101781 |
Serial |
1103 |
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| Permanent link to this record |
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Author |
Matsubara, M.; Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B. |
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| |
Title |
Attracting shallow donors : hydrogen passivation in (Al,Ga,In)-doped ZnO |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
86 |
Issue |
16 |
Pages |
165207 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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| |
Abstract |
The hydrogen interstitial and the substitutional AlZn, GaZn, and InZn are all shallow donors in ZnO and lead to n-type conductivity. Although shallow donors are expected to repel each other, we show by first-principles calculations that in ZnO these shallow donor impurities attract and form a complex, leading to a donor level deep in the band gap. This puts a limit on the n-type conductivity of (Al,Ga,In)-doped ZnO in the presence of hydrogen. |
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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 |
000310131300008 |
Publication Date |
2012-10-22 |
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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 |
|
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| |
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.836 |
Times cited |
7 |
Open Access |
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| |
Notes |
Iwt; Fwo; Bof-Noi |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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| |
Call Number |
UA @ lucian @ c:irua:101780 |
Serial |
202 |
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| Permanent link to this record |
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Author |
Li, M.R.; Retuerto, M.; Bok Go, Y.; Emge, T.J.; Croft, M.; Ignatov, A.; Ramanujachary, K.V.; Dachraoui, W.; Hadermann, J.; Tang, M.B.; Zhao, J.T.; Greenblatt, M.; |
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Title |
Synthesis, crystal structure, and properties of KSbO3-type Bi3Mn1.9Te1.1O11 |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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| |
Volume |
197 |
Issue |
|
Pages |
543-549 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Single crystals of Bi3Mn1.9Te1.1O11 were prepared from NaCl+KCl flux. This compound adopts KSbO3-type crystal structure as evidenced by electron and single crystal X-ray diffraction analysis. The three-dimensional channel structure is formed by corner-sharing octahedral (Mn0.63Te0.37)2O10 dimers and two identical (Bi1)4(Bi2)2 interpenetrating lattices. The intra-dimer Mn/TeMn/Te distances in Bi3Mn1.9Te1.1O11 are short and are consistent with weak metalmetal interactions. The mixed oxidation state of manganese and the edge-sharing octahedral features are confirmed by X-ray near edge absorption spectroscopy measurements, which indicate Bi3(MnIII1.1MnIV0.8)TeVI1.1O11 with 57.7% Mn3+ and 42.3% Mn4+. The partial substitution of Te for Mn perturbs long-range magnetic interactions, thereby destroying the ferromagnetic ordering found in Bi3Mn3O11 (TC=150 K). |
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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 |
Editor |
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| |
Language |
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Wos |
000312281000076 |
Publication Date |
2012-07-25 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
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| |
ISSN |
0022-4596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.299 |
Times cited |
13 |
Open Access |
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| |
Notes |
|
Approved |
Most recent IF: 2.299; 2013 IF: 2.200 |
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| |
Call Number |
UA @ lucian @ c:irua:101779 |
Serial |
3452 |
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| Permanent link to this record |
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| |
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Author |
Goris, B.; Bals, S.; van den Broek, W.; Carbó-Argibay, E.; Gómez-Graña, S.; Liz-Marzán, L.M.; Van Tendeloo, G. |
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Title |
Atomic-scale determination of surface facets in gold nanorods |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Nature materials |
Abbreviated Journal |
Nat Mater |
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| |
Volume |
11 |
Issue |
11 |
Pages |
930-935 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
It is widely accepted that the physical properties of nanostructures depend on the type of surface facets1, 2. For Au nanorods, the surface facets have a major influence on crucial effects such as reactivity and ligand adsorption and there has been controversy regarding facet indexing3, 4. Aberration-corrected electron microscopy is the ideal technique to study the atomic structure of nanomaterials5, 6. However, these images correspond to two-dimensional (2D) projections of 3D nano-objects, leading to an incomplete characterization. Recently, much progress was achieved in the field of atomic-resolution electron tomography, but it is still far from being a routinely used technique. Here we propose a methodology to measure the 3D atomic structure of free-standing nanoparticles, which we apply to characterize the surface facets of Au nanorods. This methodology is applicable to a broad range of nanocrystals, leading to unique insights concerning the connection between the structure and properties of nanostructures. |
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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 |
Editor |
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| |
Language |
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Wos |
000310434600015 |
Publication Date |
2012-10-19 |
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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 |
|
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| |
ISSN |
1476-1122;1476-4660; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
39.737 |
Times cited |
261 |
Open Access |
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| |
Notes |
262348 ESMI; Hercules 3; 24691 COUNTATOMS; 267867 PLASMAQUO |
Approved |
Most recent IF: 39.737; 2012 IF: 35.749 |
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| |
Call Number |
UA @ lucian @ c:irua:101778 |
Serial |
182 |
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| Permanent link to this record |
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| |
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Author |
Evers, W.H.; Goris, B.; Bals, S.; Casavola, M.; de Graaf, J.; van Roij, R.; Dijkstra, M.; Vanmaekelbergh, D. |
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Title |
Low-dimensional semiconductor superlattices formed by geometric control over nanocrystal attachment |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
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| |
Volume |
13 |
Issue |
6 |
Pages |
2317-2323 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
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| |
Abstract |
Oriented attachment, the process in which nanometer-sized crystals fuse by atomic bonding of specific crystal facets, is expected to be more difficult to control than nanocrystal self-assembly that is driven by entropic factors or weak van der Waals attractions. Here, we present a study of oriented attachment of PbSe nanocrystals that counteract this tuition. The reaction was studied in a thin film of the suspension casted on an immiscible liquid at a given temperature. We report that attachment can be controlled such that it occurs with one type of facets exclusively. By control of the temperature and particle concentration we obtain one- or two-dimensional PbSe single crystals, the latter with a honeycomb or square superimposed periodicity in the nanometer range. We demonstrate the ability to convert these PbSe superstructures into other semiconductor compounds with the preservation of crystallinity and geometry. |
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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 |
Editor |
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| |
Language |
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Wos |
000320485100001 |
Publication Date |
2012-10-11 |
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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 |
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| |
ISSN |
1530-6984;1530-6992; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
12.712 |
Times cited |
206 |
Open Access |
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| |
Notes |
262348 ESMI; Hercules 3 |
Approved |
Most recent IF: 12.712; 2013 IF: 12.940 |
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| |
Call Number |
UA @ lucian @ c:irua:101777 |
Serial |
1847 |
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| Permanent link to this record |
