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Records |
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Author |
Matulis, A.; Peeters, F.M. |
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Title |
Renormalized perturbation series for quantum dots |
Type |
A1 Journal article |
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Year |
1994 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
6 |
Issue |
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Pages |
7751-7762 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Place of Publication |
London |
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Wos |
A1994PH49300013 |
Publication Date |
2002-08-25 |
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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 |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.346 |
Times cited |
77 |
Open Access |
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Notes |
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Approved |
PHYSICS, MULTIDISCIPLINARY 6/79 Q1 # |
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Call Number |
UA @ lucian @ c:irua:9368 |
Serial |
2873 |
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Author |
Copley, J.R.D.; Michel, K.H. |
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Title |
Neutron and X-ray-scattering cross sections of orientationally disordered solid C60 |
Type |
A1 Journal article |
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Year |
1993 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
5 |
Issue |
26 |
Pages |
4353-4370 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Differential cross sections for neutron and x-ray scattering have been derived for the orientationally disordered phase of solid C60. Interaction centres are placed at nuclei and at the centres of interatomic bonds. Bragg and diffuse scattering cross sections, for single crystals and for powders, are formulated using symmetry-adapted rotator functions. Thermal averages are calculated taking account of crystal field effects. Thermally averaged orientational distribution functions have also been calculated. |
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Place of Publication |
London |
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Wos |
A1993LK74100008 |
Publication Date |
2002-08-25 |
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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 |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.346 |
Times cited |
34 |
Open Access |
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Notes |
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Approved |
MATERIALS SCIENCE, MULTIDISCIPLINARY 96/271 Q2 # |
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Call Number |
UA @ lucian @ c:irua:102972 |
Serial |
2298 |
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Author |
Leenaerts, O.; Partoens, B.; Peeters, F.M.; Volodin, A.; van Haesendonck, C. |
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Title |
The work function of few-layer graphene |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
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| |
Volume |
29 |
Issue |
3 |
Pages |
035003 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
A theoretical and experimental study of the work function of few-layer graphene is reported. The influence of the number of layers on the work function is investigated in the presence of a substrate, a molecular dipole layer, and combinations of the two. The work function of few-layer graphene is almost independent of the number of layers with only a difference between monolayer and multilayer graphene of about 60 meV. In the presence of a charge-donating substrate the charge distribution is found to decay exponentially away from the substrate and this is directly reflected in the work function of few-layer graphene. A dipole layer changes the work function only when placed in between the substrate and few-layer graphene through a change of the charge transfer between the two. |
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Wos |
000425250600002 |
Publication Date |
2016-11-16 |
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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 |
0953-8984 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
61 |
Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:164938 |
Serial |
8760 |
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Author |
Moors, K.; Sorée, B.; Magnus, W. |
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Title |
Validity criteria for Fermi's golden rule scattering rates applied to metallic nanowires |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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| |
Volume |
28 |
Issue |
28 |
Pages |
365302 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Fermi's golden rule underpins the investigation of mobile carriers propagating through various solids, being a standard tool to calculate their scattering rates. As such, it provides a perturbative estimate under the implicit assumption that the effect of the interaction Hamiltonian which causes the scattering events is sufficiently small. To check the validity of this assumption, we present a general framework to derive simple validity criteria in order to assess whether the scattering rates can be trusted for the system under consideration, given its statistical properties such as average size, electron density, impurity density et cetera. We derive concrete validity criteria for metallic nanowires with conduction electrons populating a single parabolic band subjected to different elastic scattering mechanisms: impurities, grain boundaries and surface roughness. |
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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 |
000380754400013 |
Publication Date |
2016-07-12 |
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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 |
0953-8984 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.649 |
Times cited |
2 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 2.649 |
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Call Number |
UA @ lucian @ c:irua:135011 |
Serial |
4274 |
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Author |
Cukaric, N.A.; Partoens, B.; Tadic, M.Z.; Arsoski, V.V.; Peeters, F.M. |
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Title |
The 30-band k . p theory of valley splitting in silicon thin layers |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
28 |
Issue |
28 |
Pages |
195303 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The valley splitting of the conduction-band states in a thin silicon-on-insulator layer is investigated using the 30-band k . p theory. The system composed of a few nm thick Si layer embedded within thick SiO2 layers is analyzed. The valley split states are found to cross periodically with increasing quantum well width, and therefore the energy splitting is an oscillatory function of the quantum well width, with period determined by the wave vector K-0 of the conduction band minimum. Because the valley split states are classified by parity, the optical transition between the ground hole state and one of those valley split conduction band states is forbidden. The oscillations in the valley splitting energy decrease with electric field and with smoothing of the composition profile between the well and the barrier by diffusion of oxygen from the SiO2 layers to the Si quantum well. Such a smoothing also leads to a decrease of the interband transition matrix elements. The obtained results are well parametrized by the effective two-valley model, but are found to disagree from previous 30-band calculations. This discrepancy could be traced back to the fact that the basis for the numerical solution of the eigenproblem must be restricted to the first Brillouin zone in order to obtain quantitatively correct results for the valley splitting. |
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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 |
000374394700009 |
Publication Date |
2016-04-19 |
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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 |
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Series Issue |
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Edition |
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ISSN |
0953-8984 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
2.649 |
Times cited |
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Open Access |
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Notes |
; This work was supported by the Ministry of Education, Science, and Technological Development of Serbia, the Flemish fund for Scientific Research (FWO-Vl), and the Methusalem programme of the Flemish government. ; |
Approved |
Most recent IF: 2.649 |
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Call Number |
UA @ lucian @ c:irua:133610 |
Serial |
4261 |
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Author |
Sivek, J.; Sahin, H.; Partoens, B.; Peeters, F.M. |
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Title |
Giant magnetic anisotropy in doped single layer molybdenum disulfide and fluorographene |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
28 |
Issue |
28 |
Pages |
195301 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Stable monolayer materials based on existing, well known and stable two-dimensional crystal fluorographene and molybdenum disulfide are predicted to exhibit a huge magnetocrystalline anisotropy when functionalized with adsorbed transition metal atoms at vacant sides. Ab initio calculations within the density-functional theory formalism were performed to investigate the adsorption of the transitional metals in a single S (or F) vacancy of monolayer molybdenum disulfide (or fluorographene). We found strong bonding of the transitional metal atoms to the vacant sites with binding energies ranging from 2.5 to 5.2 eV. Our calculations revealed that these systems with adsorbed metal atoms exhibit a magnetic anisotropy, specifically the structures including Os and Ir show a giant magnetocrystalline anisotropy energy of 31-101 meV. Our results demonstrate the possibility of obtaining stable monolayer materials with huge magnetocrystalline anisotropy based on preexisting, well known and stable two-dimensional crystals: fluorographene and molybdenum disulfide. We believe that the results obtained here are useful not only for deeper understanding of the origin of magnetocrystalline anisotropy but also for the design of monolayer optoelectronic devices with novel functionalities. |
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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 |
000374394700007 |
Publication Date |
2016-04-13 |
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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 |
0953-8984 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.649 |
Times cited |
7 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.649 |
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Call Number |
UA @ lucian @ c:irua:133611 |
Serial |
4185 |
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Author |
Chen, Y.; Hong-Yu, W.; Peeters, F.M.; Shanenko, A.A. |
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Title |
Quantum-size effects and thermal response of anti-Kramer-Pesch vortex core |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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| |
Volume |
27 |
Issue |
27 |
Pages |
125701 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Since the 1960's it has been well known that the basic superconductive quantities can exhibit oscillations as functions of the thickness (diameter) in superconducting nanofilms (nanowires) due to the size quantization of the electronic spectrum. However, very little is known about the effects of quantum confinement on the microscopic properties of vortices. Based on a numerical solution to the Bogoliubov-de Gennes equations, we study the quantum-size oscillations of the vortex core resulting from the sequential interchange of the Kramer-Pesch and anti-Kramer-Pesch regimes with changing nanocylinder radius. The physics behind the anti-Kramer-Pesch anomaly is displayed by utilizing a semi-analytical Anderson approximate solution. We also demonstrate that the anti-Kramer-Pesch vortex core is robust against thermal smearing and results in a distinctive two-maxima structure in the local density of states, which can be used to identify the existence of the anti-Kramer-Pesch vortex. |
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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 |
000351294700018 |
Publication Date |
2015-03-09 |
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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 |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.649 |
Times cited |
4 |
Open Access |
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Notes |
; This work was supported by the National Natural Science Foundation of China under Grant No. NSFC-11304134, the Flemish Science Foundation (FWO-Vl), and the Methusalem program. AAS acknowledges the support of the Brazilian agencies CNPq (grants 307552/2012-8 and 141911/2012-3) and FACEPE (APQ-0589-1.05/08). WHY acknowledges the support of Scientific Research Fund of Zhejiang Provincial Education Department (Y201120994). ; |
Approved |
Most recent IF: 2.649; 2015 IF: 2.346 |
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Call Number |
c:irua:125460 |
Serial |
2787 |
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| Permanent link to this record |
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Author |
Ravi Kishore, V.V.; Partoens, B.; Peeters, F.M. |
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Title |
Electronic and optical properties of core-shell nanowires in a magnetic field |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
26 |
Issue |
9 |
Pages |
095501-95512 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The electronic and optical properties of zincblende nanowires are investigated in the presence of a uniform magnetic field directed along the [001] growth direction within the k . p method. We focus our numerical study on core-shell nanowires consisting of the III-V materials GaAs, AlxGa1-xAs and AlyGa1-y/0.51In0.49P. Nanowires with electrons confined in the core exhibit a Fock-Darwin-like spectrum, whereas nanowires with electrons confined in the shell show Aharonov-Bohm oscillations. Thus, by properly choosing the core and the shell materials of the nanowire, the optical properties in a magnetic field can be tuned in very different ways. |
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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 |
000331954500006 |
Publication Date |
2014-02-12 |
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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 |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.649 |
Times cited |
10 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish government. ; |
Approved |
Most recent IF: 2.649; 2014 IF: 2.346 |
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Call Number |
UA @ lucian @ c:irua:115845 |
Serial |
998 |
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Author |
Nasr Esfahani, D.; Covaci, L.; Peeters, F.M. |
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Title |
Surface correlation effects in two-band strongly correlated slabs |
Type |
A1 Journal article |
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Year |
2014 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
26 |
Issue |
7 |
Pages |
075601-75609 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Using an extension of the Gutzwiller approximation for an inhomogeneous system, we study the two-band Hubbard model with unequal band widths for a slab geometry. The aim is to investigate the mutual effect of individual bands on the spatial distribution of quasi-particle weight and charge density, especially near the surface of the slab. The main effect of the difference in band width is the presence of two different length scales corresponding to the quasi-particle profile of each band. This is enhanced in the vicinity of the critical interaction of the narrow band where an orbitally selective Mott transition occurs and a surface dead layer forms for the narrow band. For the doped case, two different regimes of charge transfer between the surface and the bulk of the slab are revealed. The charge transfer from surface/ center to center/ surface depends on both the doping level and the average relative charge accumulated in each band. Such effects could also be of importance when describing the accumulation of charges at the interface between structures made of multi-band strongly correlated 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 |
London |
Editor |
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Language |
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Wos |
000330719500009 |
Publication Date |
2014-01-29 |
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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 |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.649 |
Times cited |
1 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program of the Flemish government. One of us (LC) is a postdoctoral fellow of the FWO-Vl. ; |
Approved |
Most recent IF: 2.649; 2014 IF: 2.346 |
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Call Number |
UA @ lucian @ c:irua:115723 |
Serial |
3395 |
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| Permanent link to this record |
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Author |
Oncel, N.; Çakir, D.; Dil, J.H.; Slomski, B.; Landolt, G. |
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Title |
Angle-resolved synchrotron photoemission and density functional theory on the iridium modified Si(111) surface |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
26 |
Issue |
28 |
Pages |
285501 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The physical and electronic properties of the Ir modified Si(1 1 1) surface have been investigated with the help of angle resolved photoemission spectroscopy and density functional theory. The surface consists of Ir-ring clusters that form a root 7 x root 7 -R19.1 degrees reconstruction. A comparison between the measured and calculated band structure of the system reveals that the dispersions of the projected bulk states and the states originating from '1x1' domains are heavily modified due to Umklapp scattering from the surface Brillouin zone. Density of states calculations show that Ir-ring clusters contribute to the states in the vicinity of the Fermi level. |
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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 |
000338830300019 |
Publication Date |
2014-06-19 |
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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 |
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Series Issue |
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Edition |
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ISSN |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
2.649 |
Times cited |
4 |
Open Access |
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Notes |
; This work was partially supported by the National Science Foundation (DMR-1306101), North Dakota EPSCoR office (NSF grant #EPS-814442), the University of North Dakota and the Swiss National Science Foundation. Computer resources used in this work partially provided by Computational Research Center (HPC-Linux cluster) at UND and TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). ; |
Approved |
Most recent IF: 2.649; 2014 IF: 2.346 |
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Call Number |
UA @ lucian @ c:irua:118636 |
Serial |
114 |
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Author |
Petrovic, M.D.; Peeters, F.M.; Chaves, A.; Farias, G.A. |
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Title |
Conductance maps of quantum rings due to a local potential perturbation |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
25 |
Issue |
49 |
Pages |
495301-495309 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We performed a numerical simulation of the dynamics of a Gaussian shaped wavepacket inside a small sized quantum ring, smoothly connected to two leads and exposed to a perturbing potential of a biased atomic force microscope tip. Using the Landauer formalism, we calculated conductance maps of this system in the case of single and two subband transport. We explain the main features in the conductance maps as due to the AFM tip influence on the wavepacket phase and amplitude. In the presence of an external magnetic field, the tip modifies the phi(0) periodic Aharonov-Bohm oscillation pattern into a phi(0)/2 periodic Al'tshuler-Aronov-Spivak oscillation pattern. Our results in the case of multiband transport suggest tip selectivity to higher subbands, making them more observable in the total |
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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 |
000327181400002 |
Publication Date |
2013-11-01 |
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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 |
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 |
12 |
Open Access |
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| |
Notes |
; This work was supported by the Methusalem programme of the Flemish government, the CNPq-FWO bilateral programme and PNPD and FUNCAP/PRONEX grants. ; |
Approved |
Most recent IF: 2.649; 2013 IF: 2.223 |
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Call Number |
UA @ lucian @ c:irua:112694 |
Serial |
478 |
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| Permanent link to this record |
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Author |
Dabaghmanesh, S.; Saniz, R.; Amini, M.N.; Lamoen, D.; Partoens, B. |
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| |
Title |
Perovskite transparent conducting oxides : an ab initio study |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
|
| |
Volume |
25 |
Issue |
41 |
Pages |
415503 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
| |
Abstract |
We present an ab initio study of the electronic structure and of the formation energies of various point defects in BaSnO3 and SrGeO3. We show that La and Y impurities substituting Ba or Sr are shallow donors with a preferred 1 + charge state. These defects have a low formation energy within all the suitable equilibrium growth conditions considered. Oxygen vacancies behave as shallow donors as well, preferring the 2 + charge state. Their formation energies, however, are higher in most growth conditions, indicating a limited contribution to conductivity. The calculated electron effective mass in BaSnO3, with a value of 0.21 me, and the very high mobility reported recently in La-doped BaSnO3 single-crystals, suggest that remarkably low scattering rates can be achieved in the latter. In the case of SrGeO3, our results point to carrier density and mobility values in the low range for typical polycrystalline TCOs, in line with experiment. |
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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 |
000324920400011 |
Publication Date |
2013-09-24 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
17 |
Open Access |
|
|
| |
Notes |
FWO;Hercules |
Approved |
Most recent IF: 2.649; 2013 IF: 2.223 |
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| |
Call Number |
UA @ lucian @ c:irua:110495 |
Serial |
2574 |
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| Permanent link to this record |
| |
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| |
|
Author |
Dixit, H.; Lamoen, D.; Partoens, B. |
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| |
Title |
Quasiparticle band structure of rocksalt-CdO determined using maximally localized Wannier functions |
Type |
A1 Journal article |
| |
Year |
2013 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
|
| |
Volume |
25 |
Issue |
3 |
Pages |
035501-35505 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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| |
Abstract |
CdO in the rocksalt structure is an indirect band gap semiconductor. Thus, in order to determine its band gap one needs to calculate the complete band structure. However, in practice, the exact evaluation of the quasiparticle band structure for the large number of k-points which constitute the different symmetry lines in the Brillouin zone can be an extremely demanding task compared to the standard density functional theory (DFT) calculation. In this paper we report the full quasiparticle band structure of CdO using a plane-wave pseudopotential approach. In order to reduce the computational effort and time, we make use of maximally localized Wannier functions (MLWFs). The MLWFs offer a highly accurate method for interpolation of the DFT or GW band structure from a coarse k-point mesh in the irreducible Brillouin zone, resulting in a much reduced computational effort. The present paper discusses the technical details of the scheme along with the results obtained for the quasiparticle band gap and the electron effective mass. |
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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 |
000313100500010 |
Publication Date |
2012-12-12 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
7 |
Open Access |
|
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 2.649; 2013 IF: 2.223 |
|
| |
Call Number |
UA @ lucian @ c:irua:105296 |
Serial |
2801 |
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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 |
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Place of Publication |
London |
Editor |
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| |
Language |
|
Wos |
000308202700011 |
Publication Date |
2012-08-14 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
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 |
|
| |
Call Number |
UA @ lucian @ c:irua:101838 |
Serial |
1000 |
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| Permanent link to this record |
| |
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| |
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Author |
Croitoru, M.D.; Shanenko, A.A.; Kaun, C.C.; Peeters, F.M. |
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| |
Title |
Ultra-small metallic grains : effect of statistical fluctuations of the chemical potential on superconducting correlations and vice versa |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
|
| |
Volume |
24 |
Issue |
27 |
Pages |
275701 |
|
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Superconducting correlations in an isolated metallic grain are governed by the interplay between two energy scales: the mean level spacing delta and the bulk pairing gap Delta(0), which are strongly influenced by the position of the chemical potential with respect to the closest single-electron level. In turn superconducting correlations affect the position of the chemical potential. Within the parity projected BCS model we investigate the probability distribution of the chemical potential in a superconducting grain with randomly distributed single-electron levels. Taking into account statistical fluctuations of the chemical potential due to the pairing interaction, we find that such fluctuations have a significant impact on the critical level spacing delta(c) at which the superconducting correlations cease: the critical ratio delta(c)/Delta(0) at which superconductivity disappears is found to be increased. |
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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 |
|
Wos |
000305653100012 |
Publication Date |
2012-06-21 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
9 |
Open Access |
|
|
| |
Notes |
; This work was supported by the European Community under the Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR), the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF network INSTANS. MDC and AAS are grateful to A Vagov for stimulating discussions. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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| |
Call Number |
UA @ lucian @ c:irua:100280 |
Serial |
3793 |
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| Permanent link to this record |
| |
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| |
|
Author |
Chen, Y.; Shanenko, A.A.; Croitoru, M.D.; Peeters, F.M. |
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| |
Title |
Quantum cascades in nano-engineered superconductors : geometrical, thermal and paramagnetic effects |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
|
| |
Volume |
24 |
Issue |
26 |
Pages |
265702 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The effect of a parallel magnetic field on the orbital motion of electrons in high-quality superconducting nanowires resulting in a superconductor-to-normal transition which occurs through a cascade of jumps in the order parameter as a function of the magnetic field. Such cascades originate from the transverse size quantization that splits the conduction band into a series of subbands. Here, based on a numerical solution of the Bogoliubov-de Gennes equations for a hollow nanocylinder, we investigate how the quantum-size cascades depend on the confining geometry, i.e., by changing the cylinder radius R and its thickness d we cover the range from the nanowire-like to the nanofilm-like regime. The cascades are shown to become much less pronounced when increasing R/d, i.e., when the nanofilm-like regime is approached. When the temperature is non-zero they are thermally smoothed. This includes the spin-magnetic-field interaction which reduces the critical (depairing) parallel magnetic field H-c,H-parallel to but does not have any qualitative effect on the quantum cascades. From our calculations it is seen that the paramagnetic limiting field H-par significantly exceeds H-c,H-parallel to even in extremely narrow nanocylinders, i.e., when R, d are down to a few nanometers, and H-c,H-parallel to is only about 10% larger when switching-off the spin-magnetic-field interaction in this case. Both characteristic fields, H-c,H-parallel to and H-par, exhibit pronounced quantum-size oscillations. We demonstrate that the quantum cascades and the quantum-size oscillations survive in the presence of surface roughness. |
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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 |
000305640800014 |
Publication Date |
2012-06-07 |
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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 |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
6 |
Open Access |
|
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI) and the ESF-AQDJJ network. MDC acknowledges the support of the EU Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR). ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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| |
Call Number |
UA @ lucian @ c:irua:100281 |
Serial |
2773 |
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| Permanent link to this record |
| |
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| |
|
Author |
Dixit, H.; Saniz, R.; Cottenier, S.; Lamoen, D.; Partoens, B. |
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| |
Title |
Electronic structure of transparent oxides with the Tran-Blaha modified Becke-Johnson potential |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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| |
Volume |
24 |
Issue |
20 |
Pages |
205503-205503,9 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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| |
Abstract |
We present electronic band structures of transparent oxides calculated using the Tran-Blaha modified Becke-Johnson (TB-mBJ) potential. We studied the basic n-type conducting binary oxides In2O3, ZnO, CdO and SnO2 along with the p-type conducting ternary oxides delafossite CuXO2 (X = Al, Ga, In) and spinel ZnX2O4 (X = Co, Rh, Ir). The results are presented for calculated band gaps and effective electron masses. We discuss the improvements in the band gap determination using TB-mBJ compared to the standard generalized gradient approximation (GGA) in density functional theory (DFT) and also compare the electronic band structure with available results from the quasiparticle GW method. It is shown that the calculated band gaps compare well with the experimental and GW results, although the electron effective mass is generally overestimated. |
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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 |
000303507100009 |
Publication Date |
2012-04-27 |
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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 |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
113 |
Open Access |
|
|
| |
Notes |
Iwt; Fwo |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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| |
Call Number |
UA @ lucian @ c:irua:98222 |
Serial |
1017 |
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| Permanent link to this record |
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| |
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Author |
Chen, Y.; Shanenko, A.A.; Perali, A.; Peeters, F.M. |
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| |
Title |
Superconducting nanofilms : molecule-like pairing induced by quantum confinement |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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| |
Volume |
24 |
Issue |
18 |
Pages |
185701-185701,8 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Quantum confinement of the perpendicular motion of electrons in single-crystalline metallic superconducting nanofilms splits the conduction band into a series of single-electron subbands. A distinctive feature of such a nanoscale multi-band superconductor is that the energetic position of each subband can vary significantly with changing nanofilm thickness, substrate material, protective cover and other details of the fabrication process. It can occur that the bottom of one of the available subbands is situated in the vicinity of the Fermi level. We demonstrate that the character of the superconducting pairing in such a subband changes dramatically and exhibits a clear molecule-like trend, which is very similar to the well-known crossover from the Bardeen-Cooper-Schrieffer regime to Bose-Einstein condensation (BCS-BEC) observed in trapped ultracold fermions. For Pb nanofilms with thicknesses of 4 and 5 monolayers (MLs) this will lead to a spectacular scenario: up to half of all the Cooper pairs nearly collapse, shrinking in the lateral size (parallel to the nanofilm) down to a few nanometers. As a result, the superconducting condensate will be a coherent mixture of almost molecule-like fermionic pairs with ordinary, extended Cooper pairs. |
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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 |
000303500900018 |
Publication Date |
2012-04-05 |
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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 |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
26 |
Open Access |
|
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| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). AAS thanks A Bianconi, M D Croitoru and A V Vagov for useful discussions. AAS acknowledges the hospitality and fruitful interactions with G C Strinati, P Pieri and D Neilson during his visit to the University of Camerino, supported by the School of Advanced Studies of the University of Camerino. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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| |
Call Number |
UA @ lucian @ c:irua:98223 |
Serial |
3357 |
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| Permanent link to this record |
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Author |
Lajevardipour, A.; Neek-Amal, M.; Peeters, F.M. |
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| |
Title |
Thermomechanical properties of graphene : valence force field model approach |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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| |
Volume |
24 |
Issue |
17 |
Pages |
175303-175303,8 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Using the valence force field model of Perebeinos and Tersoff (2009 Phys. Rev. B 79 241409(R)), different energy modes of suspended graphene subjected to tensile or compressive strain are studied. By carrying out Monte Carlo simulations it is found that: (i) only for small strains (vertical bar epsilon vertical bar (sic) 0.02) is the total energy symmetrical in the strain, while it behaves completely differently beyond this threshold; (ii) the important energy contributions in stretching experiments are stretching, angle bending, an out-of-plane term, and a term that provides repulsion against pi-pi misalignment; (iii) in compressing experiments the two latter terms increase rapidly, and beyond the buckling transition stretching and bending energies are found to be constant; (iv) from stretching-compressing simulations we calculated the Young's modulus at room temperature 350 +/- 3.15 N m(-1), which is in good agreement with experimental results (340 +/- 50 N m(-1)) and with ab initio results (322-353) N m(-1); (v) molar heat capacity is estimated to be 24.64 J mol(-1) K-1 which is comparable with the Dulong-Petit value, i. e. 24.94 J mol(-1) K-1, and is almost independent of the strain; (vi) nonlinear scaling properties are obtained from height-height correlations at finite temperature; (vii) the used valence force field model results in a temperature independent bending modulus for graphene, and (viii) the Gruneisen parameter is estimated to be 0.64. |
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Address |
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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 |
000303499700012 |
Publication Date |
2012-04-05 |
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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 |
|
Edition |
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| |
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
29 |
Open Access |
|
|
| |
Notes |
; We acknowledge helpful comments by V Perebeinos, S Costamagna, A Fasolino and J H Los. This work was supported by the Flemish science foundation (FWO-Vl) and the Belgium Science Policy (IAP). ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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| |
Call Number |
UA @ lucian @ c:irua:99123 |
Serial |
3639 |
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| Permanent link to this record |
| |
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| |
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Author |
Kishore, V.V.R.; Čukarić, N.; Partoens, B.; Tadić, M.; Peeters, F.M. |
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| |
Title |
Hole subbands in freestanding nanowires : six-band versus eight-band k.p modelling |
Type |
A1 Journal article |
| |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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| |
Volume |
24 |
Issue |
13 |
Pages |
135302-135302,10 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The electronic structure of GaAs, InAs and InSb nanowires is studied using the six-band and the eight-band k.p models. The effect of the different Luttinger-like parameters (in the eight-band model) on the hole band structure is investigated. Although GaAs nanostructures are often treated within a six-band model because of the large bandgap, it is shown that an eight-band model is necessary for a correct description of its hole spectrum. The camel-back structure usually found in the six-band model is not always present in the eight-band model. This camel-back structure depends on the interaction between light and heavy holes, especially the ones with opposite spin. The latter effect is less pronounced in an eight-band model, but could be very sensitive to the Kane inter-band energy (E-P) value. |
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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 |
000302120100007 |
Publication Date |
2012-03-06 |
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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 |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
13 |
Open Access |
|
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), Belgian Science Policy (IAP) and the Ministry of Education and Science of Serbia. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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| |
Call Number |
UA @ lucian @ c:irua:97763 |
Serial |
1479 |
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| Permanent link to this record |
| |
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Author |
Neek-Amal, M.; Peeters, F.M. |
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| |
Title |
Buckled circular monolayer graphene : a graphene nano-bowl |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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| |
Volume |
23 |
Issue |
4 |
Pages |
045002-045002,8 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
We investigate the stability of circular monolayer graphene subjected to a radial load using non-equilibrium molecular dynamics simulations. When monolayer graphene is radially stressed, after some small circular strain (~0.4%) it buckles and bends into a new bowl-like shape. Young's modulus is calculated from the linear relation between stress and strain before the buckling threshold, which is in agreement with experimental results. The prediction of elasticity theory for the buckling threshold of a radially stressed plate is presented and its results are compared to the one of our atomistic simulation. The Jarzynski equality is used to estimate the difference between the free energy of the non-compressed states and the buckled states. From a calculation of the free energy we obtain the optimum radius for which the system feels the minimum boundary stress. |
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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 |
000286142800003 |
Publication Date |
2010-12-16 |
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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 |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
27 |
Open Access |
|
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 2.649; 2011 IF: 2.546 |
|
| |
Call Number |
UA @ lucian @ c:irua:88043 |
Serial |
259 |
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| Permanent link to this record |
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| |
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Author |
Varley, J.B.; Peelaers, H.; Janotti, A.; van de Walle, C.G. |
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| |
Title |
Hydrogenated cation vacancies in semiconducting oxides |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
|
| |
Volume |
23 |
Issue |
33 |
Pages |
334212,1-334212,9 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Using first-principles calculations we have studied the electronic and structural properties of cation vacancies and their complexes with hydrogen impurities in SnO2, In2O3 and β-Ga2O3. We find that cation vacancies have high formation energies in SnO2 and In2O3 even in the most favorable conditions. Their formation energies are significantly lower in β-Ga2O3. Cation vacancies, which are compensating acceptors, strongly interact with H impurities resulting in complexes with low formation energies and large binding energies, stable up to temperatures over 730 °C. Our results indicate that hydrogen has beneficial effects on the conductivity of transparent conducting oxides: it increases the carrier concentration by acting as a donor in the form of isolated interstitials, and by passivating compensating acceptors such as cation vacancies; in addition, it potentially enhances carrier mobility by reducing the charge of negatively charged scattering centers. We have also computed vibrational frequencies associated with the isolated and complexed hydrogen, to aid in the microscopic identification of centers observed by vibrational spectroscopy. |
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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 |
|
Wos |
000294060600014 |
Publication Date |
2011-08-04 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
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 |
125 |
Open Access |
|
|
| |
Notes |
; We gratefully acknowledge useful discussions with M D Mc-Cluskey, O Bierwagen and J Speck. The work was supported by the NSF MRSEC Program (DMR05-20415), the Flemish Science Foundation (FWO-VI), the Belgian American Educational Foundation, and by Saint-Gobain Research, and made use of computing facilities at CNSI (NSF grant No. CHE-0321368), TeraGrid and TACC (NSF grant No. DMR070072N), and NERSC (DOE Office of Science Contract No. DE-AC02-05CH11231). ; |
Approved |
Most recent IF: 2.649; 2011 IF: 2.546 |
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| |
Call Number |
UA @ lucian @ c:irua:92415 |
Serial |
1534 |
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| Permanent link to this record |
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| |
|
Author |
Masir, M.R.; Vasilopoulos, P.; Peeters, F.M. |
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| |
Title |
Graphene in inhomogeneous magnetic fields : bound, quasi-bound and scattering states |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
|
| |
Volume |
23 |
Issue |
31 |
Pages |
315301,1-315301,14 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The electron states in graphene-based magnetic dot and magnetic ring structures and combinations of both are investigated. The corresponding spectra are studied as a function of the radii, the strengths of the inhomogeneous magnetic field and of a uniform background field, the strength of an electrostatic barrier and the angular momentum quantum number. In the absence of an external magnetic field we have only long-lived quasi-bound and scattering states and we assess their influence on the density of states. In addition, we consider elastic electron scattering by a magnetic dot, whose average B vanishes, and show that the Hall and longitudinal resistivities, as a function of the Fermi energy, exhibit a pronounced oscillatory structure due to the presence of quasi-bound states. Depending on the dot parameters this oscillatory structure differs substantially for energies below and above the first Landau level. |
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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 |
000293008900002 |
Publication Date |
2011-07-16 |
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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 |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
38 |
Open Access |
|
|
| |
Notes |
; This work was supported by the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE, the Canadian NSERC grant no. OGP0121756 and the Belgian Science Policy (IAP). We acknowledge discussions and correspondence with Professor A Matulis. ; |
Approved |
Most recent IF: 2.649; 2011 IF: 2.546 |
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| |
Call Number |
UA @ lucian @ c:irua:91176 |
Serial |
1372 |
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| Permanent link to this record |
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| |
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Author |
Rakhimov, K.Y.; Chaves, A.; Farias, G.A.; Peeters, F.M. |
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| |
Title |
Wavepacket scattering of Dirac and Schrödinger particles on potential and magnetic barriers |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
|
| |
Volume |
23 |
Issue |
27 |
Pages |
275801,1-275801,16 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
We investigate the dynamics of a charged particle moving in a graphene layer and in a two-dimensional electron gas, where it obeys the Dirac and the Schrödinger equations, respectively. The charge carriers are described as Gaussian wavepackets. The dynamics of the wavepackets is studied numerically by solving both quantum-mechanical and relativistic equations of motion. The scattering of such wavepackets by step-like magnetic and potential barriers is analysed for different values of wavepacket energy and width. We find: (1) that the average position of the wavepacket does not coincide with the classical trajectory, and (2) that, for slanted incidence, the path of the centre of mass of the wavepacket does not have to penetrate the barrier during the scattering process. Trembling motion of the charged particle in graphene is observed in the absence of an external magnetic field and can be enhanced by a substrate-induced mass term. |
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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 |
|
Wos |
000291993600009 |
Publication Date |
2011-06-18 |
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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 |
|
| |
Impact Factor |
2.649 |
Times cited |
32 |
Open Access |
|
|
| |
Notes |
; Discussions with A Matulis are gratefully acknowledged. KR is beneficiary of a mobility grant from the Belgian Federal Science Policy Office, co-funded by the European Commission and was supported in part by a grant of the Third World Academy of Sciences (ref. 09-188 RG/PHYS/AS-I). In addition, this work was financially supported by CNPq, under contract NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES, the Bilateral programme between Flanders and Brazil, the joint project CNPq-FWO, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 2.649; 2011 IF: 2.546 |
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| |
Call Number |
UA @ lucian @ c:irua:90880 |
Serial |
3908 |
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| Permanent link to this record |
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Author |
Hao, Y.L.; Djotyan, A.P.; Avetisyan, A.A.; Peeters, F.M. |
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| |
Title |
D- shallow donor near a semiconductor-metal and a semiconductor-dielectric interface |
Type |
A1 Journal article |
| |
Year |
2011 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
|
| |
Volume |
23 |
Issue |
11 |
Pages |
115303,1-115313,9 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The ground state energy and the extent of the wavefunction of a negatively charged donor (D − ) located near a semiconductormetal or a semiconductordielectric interface are obtained. We apply the effective mass approximation and use a variational two-electron wavefunction that takes into account the influence of all image charges that arise due to the presence of the interface, as well as the correlation between the two electrons bound to the donor. For a semiconductormetal interface, the D − binding energy is enhanced for donor positions d > 1.5aB (aB is the effective Bohr radius) due to the additional attraction of the electrons with their images. When the donor approaches the interface (i.e. d < 1.5aB) the D − binding energy drops and eventually it becomes unbound. For a semiconductordielectric (or a semiconductorvacuum) interface the D − binding energy is reduced for any donor position as compared to the bulk case and the system becomes rapidly unbound when the donor approaches the interface. |
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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 |
000287969200013 |
Publication Date |
2011-03-04 |
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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 |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
5 |
Open Access |
|
|
| |
Notes |
; This work was supported by the Belgian Science Policy (IAP) and the Brazilian Science Foundation CNPq. One of us (AAA) was supported by a fellowship from the Belgian Federal Science Policy Office (IAP). ; |
Approved |
Most recent IF: 2.649; 2011 IF: 2.546 |
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| |
Call Number |
UA @ lucian @ c:irua:88828 |
Serial |
3528 |
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| Permanent link to this record |
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| |
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Author |
Masir, M.R.; Vasilopoulos, P.; Peeters, F.M. |
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| |
Title |
Kronig-Penney model of scalar and vector potentials in graphene |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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| |
Volume |
22 |
Issue |
46 |
Pages |
465302,1-465302,10 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
We consider a one-dimensional (1D) superlattice (SL) on graphene consisting of very high and very thin (δ-function) magnetic and potential barriers with zero average potential and zero magnetic field. We calculate the energy spectrum analytically, study it in different limiting cases, and determine the condition under which an electron beam incident on an SL is highly collimated along its direction. In the absence of the magnetic SL the collimation is very sensitive to the value of W/Ws and is optimal for W/Ws = 1, where W is the distance between the positive and negative barriers and L = W + Ws is the size of the unit cell. In the presence of only the magnetic SL the collimation decreases and the symmetry of the spectrum around ky is broken for W/Ws\neq 1 . In addition, a gap opens which depends on the strength of the magnetic field. We also investigate the effect of spatially separated potential and magnetic δ-function barriers and predict a better collimation in specific cases. |
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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 |
000283838800004 |
Publication Date |
2010-11-05 |
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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 |
|
Edition |
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| |
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
41 |
Open Access |
|
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI), the Belgian Science Policy (IAP), and the Canadian NSERC Grant No. OGP0121756. ; |
Approved |
Most recent IF: 2.649; 2010 IF: 2.332 |
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| |
Call Number |
UA @ lucian @ c:irua:85807 |
Serial |
1767 |
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| Permanent link to this record |
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Author |
Ferreira, W.P.; Farias, G.A.; Peeters, F.M. |
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Title |
A two-component mixture of charged particles confined in a channel: melting |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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| |
Volume |
22 |
Issue |
28 |
Pages |
11 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The melting of a binary system of charged particles confined in a quasi-one-dimensional parabolic channel is studied through Monte Carlo simulations. At zero temperature the particles are ordered in parallel chains. The melting is anisotropic and different melting temperatures are obtained according to the spatial direction, and the different kinds of particles present in the system. Melting is very different for the single-, two- and four-chain configurations. A temperature induced structural phase transition is found between two different four-chain ordered states which is absent in the mono-disperse system. In the mixed regime, where the two kinds of particles are only slightly different, melting is almost isotropic and a thermally induced homogeneous distribution of the distinct kinds of charges is observed. |
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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 |
000279257300023 |
Publication Date |
2010-06-16 |
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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 |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
10 |
Open Access |
|
|
| |
Notes |
; This work was supported by CNPq, the Flemish Science Foundation (FWO-V1) and the bilateral program between Flanders and Brazil. ; |
Approved |
Most recent IF: 2.649; 2010 IF: 2.332 |
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| |
Call Number |
UA @ lucian @ c:irua:83862 |
Serial |
3771 |
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| Permanent link to this record |
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Author |
Dixit, H.; Saniz, R.; Lamoen, D.; Partoens, B. |
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Title |
The quasiparticle band structure of zincblende and rocksalt ZnO |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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| |
Volume |
22 |
Issue |
12 |
Pages |
125505,1-125505,7 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
We present the quasiparticle band structure of ZnO in its zincblende (ZB) and rocksalt (RS) phases at the Γ point, calculated within the GW approximation. The effect of the pd hybridization on the quasiparticle corrections to the band gap is discussed. We compare three systems, ZB-ZnO which shows strong pd hybridization and has a direct band gap, RS-ZnO which is also hybridized but includes inversion symmetry and therefore has an indirect band gap, and ZB-ZnS which shows a weaker hybridization due to a change of the chemical species from oxygen to sulfur. The quasiparticle corrections are calculated with different numbers of valence electrons in the Zn pseudopotential. We find that the Zn20 + pseudopotential is essential for the adequate treatment of the exchange interaction in the self-energy. The calculated GW band gaps are 2.47 eV and 4.27 eV respectively, for the ZB and RS phases. The ZB-ZnO band gap is underestimated compared to the experimental value of 3.27 by ~ 0.8 eV. The RS-ZnO band gap compares well with the experimental value of 4.5 eV. The underestimation for ZB-ZnO is correlated with the strong pd hybridization. The GW band gap for ZnS is 3.57 eV, compared to the experimental value of 3.8 eV. |
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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 |
000275496600010 |
Publication Date |
2010-03-13 |
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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 |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
53 |
Open Access |
|
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| |
Notes |
Iwt; Fwo; Bof-Nio |
Approved |
Most recent IF: 2.649; 2010 IF: 2.332 |
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| |
Call Number |
UA @ lucian @ c:irua:81531 |
Serial |
2802 |
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| Permanent link to this record |
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Author |
Chen, Y.; Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M. |
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Title |
Superconducting nanowires: quantum confinement and spatially dependent Hartree-Fock potential |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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| |
Volume |
21 |
Issue |
43 |
Pages |
435701,1-435701,7 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
It is well known that, in bulk, the solution of the Bogoliubovde Gennes equations is the same whether or not the HartreeFock term is included. Here the HartreeFock potential is position independent and so gives the same contribution to both the single-electron energies and the Fermi level (the chemical potential). Thus, the single-electron energies measured from the Fermi level (they control the solution) stay the same. This is not the case for nanostructured superconductors, where quantum confinement breaks the translational symmetry and results in a position-dependent HartreeFock potential. In this case its contribution to the single-electron energies depends on the relevant quantum numbers. We numerically solved the Bogoliubovde Gennes equations with the HartreeFock term for a clean superconducting nanocylinder and found a shift of the curve representing the thickness-dependent oscillations of the critical superconducting temperature to larger diameters. |
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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 |
000270642700012 |
Publication Date |
2009-10-09 |
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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 |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
12 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 2.649; 2009 IF: 1.964 |
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| |
Call Number |
UA @ lucian @ c:irua:79162 |
Serial |
3360 |
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| Permanent link to this record |
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Author |
Pereira, J.M.; Peeters, F.M.; Costa Filho, R.N.; Farias, G.A. |
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Title |
Valley polarization due to trigonal warping on tunneling electrons in graphene |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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| |
Volume |
21 |
Issue |
4 |
Pages |
045301,1-045301,4 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The effect of trigonal warping on the transmission of electrons tunneling through potential barriers in graphene is investigated. We present calculations of the transmission coefficient for single and double barriers as a function of energy, incidence angle and barrier heights. The results show remarkable valley-dependent directional effects for barriers oriented parallel to the armchair or parallel to the zigzag direction. These results indicate that electrostatic gates can be used as valley filters in graphene-based devices. |
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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 |
|
Wos |
000262354700004 |
Publication Date |
2008-12-20 |
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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 |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
2.649 |
Times cited |
78 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 2.649; 2009 IF: 1.964 |
|
| |
Call Number |
UA @ lucian @ c:irua:75736 |
Serial |
3834 |
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| Permanent link to this record |
