Records |
Author |
Cabral, L.R.E.; de Aquino, B.R.C.H.T.; de Souza Silva, C.C.; Milošević, M.V.; Peeters, F.M. |
Title |
Two-shell vortex and antivortex dynamics in a Corbino superconducting disk |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
93 |
Issue |
93 |
Pages |
014515 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We examine theoretically the dynamics of two vortex shells in pinning-free superconducting thin disks in the Corbino geometry. In the first considered case, the inner shell is composed of vortices and the outer one of antivortices, corresponding to a state induced by the stray field of an off-plane magnetic dipole placed on top of the superconductor. In the second considered case, both shells comprise vortices induced by a homogeneous external field. We derive the equation of motion for each shell within the Bardeen-Stephen model and study the dynamics analytically by assuming both shells are rigid and commensurate. In both cases, two distinct regimes for vortex shell motion are identified: For low applied currents the entire configuration rotates rigidly, while above a threshold current the shells decouple from each other and rotate at different angular velocities. Analytical expressions for the decoupling current, the recombination time in the decoupled phases, as well as the voltage-current characteristics are presented. Our analytical results are in excellent agreement with numerical molecular dynamics simulations of the full many-vortex problem. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000368481600003 |
Publication Date |
2016-01-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121; 1550-235x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
7 |
Open Access |
|
Notes |
; This work was supported by the Brazilian Science Agencies CAPES, CNPq, and FACEPE under Grants No. APQ-1381-1.05/12, No. APQ 2017-1.05/12, and No. APQ-0598/1.05-08 and by EU-COST Action No. MP1201 and the Research Foundation-Flanders (FWO). ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:131541 |
Serial |
4270 |
Permanent link to this record |
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Author |
Piña, J.C.; de Souza Silva, C.C.; Milošević, M.V. |
Title |
Optimizing mesoscopic two-band superconductors for observation of fractional vortex states |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
Volume |
503 |
Issue |
|
Pages |
48-51 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using the two-component Ginzburg-Landau model, we investigate the effect of sample size and magnitude and homogeneity of external magnetic field on the stability of fractional vortex states in a mesoscopic two-band superconducting disk. We found that each fractional state has a preferable sample size, for which the range of applied field in which the state is stable is pronouncedly large. Vice versa, there exists an optimal magnitude of applied field for which a large range of possible sample radii will support the considered fractional state. Finally, we show that the stability of fractional states can be enhanced even further by magnetic nanostructuring of the sample, i.e. by suitably chosen geometrical parameters and magnetic moment of a ferromagnetic dot placed on top of the superconducting disk. (C) 2014 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000340070600010 |
Publication Date |
2014-05-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.404 |
Times cited |
5 |
Open Access |
|
Notes |
; This work was supported by the Brazilian science agencies CNPq and FACEPE, Grant APQ-2017-1.05/12. MVM acknowledges support from the CAPES-PVE program. ; |
Approved |
Most recent IF: 1.404; 2014 IF: 0.942 |
Call Number |
UA @ lucian @ c:irua:118743 |
Serial |
2494 |
Permanent link to this record |
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|
|
Author |
Tahir, M.; Vasilopoulos, P.; Peeters, F.M. |
Title |
Quantum magnetotransport properties of a MoS2 monolayer |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
93 |
Issue |
93 |
Pages |
035406 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study transport properties of a MoS2 monolayer in the presence of a perpendicular magnetic field B. We derive and discuss its band structure and take into account spin and valley Zeeman effects. Compared to a conventional two-dimensional electron gas, these effects lead to new quantum Hall plateaus and new peaks in the longitudinal resistivity as functions of the magnetic field. The field B leads to a significant enhancement of the spin splitting in the conduction band, to a beating of the Shubnikov-de Haas (SdH) oscillations in the low-field regime, and to their splitting in the high-field regime. The Zeeman fields suppress significantly the beating of the SdH oscillations in the low-field regime and strongly enhance their splitting at high fields. The spin and valley polarizations show a similar beating pattern at low fields and are clearly separated at high fields in which they attain a value higher than 90%. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000367663500003 |
Publication Date |
2016-01-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121; 1550-235x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
42 |
Open Access |
|
Notes |
; This work was supported by the Canadian NSERC Grant No. OGP0121756 (M.T., P.V.) and by the Flemish Science Foundation (FWO-Vl) (F.M.P.). ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:131093 |
Serial |
4233 |
Permanent link to this record |
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Author |
Missault, N.; Vasilopoulos, P.; Vargiamidis, V.; Peeters, F.M.; Van Duppen, B. |
Title |
Spin- and valley-dependent transport through arrays of ferromagnetic silicene junctions |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
92 |
Issue |
92 |
Pages |
195423 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study ballistic transport of Dirac fermions in silicene through arrays of barriers, of width d, in the presence of an exchange field M and a tunable potential of height U or depth-U. The spin-and valley-resolved conductances as functions of U or M, exhibit resonances away from the Dirac point (DP) and close to it a pronounced dip that becomes a gap when a critical electric field E-z is applied. This gap widens by increasing the number of barriers and can be used to realize electric field-controlled switching of the current. The spin p(s) and valley p(v) polarizations of the current near the DP increase with Ez or M and can reach 100% for certain of their values. These field ranges widen significantly by increasing the number of barriers. Also, ps and pv oscillate nearly periodically with the separation between barriers or wells and can be inverted by reversing M. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000364998100006 |
Publication Date |
2015-11-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121; 1550-235x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
54 |
Open Access |
|
Notes |
; This work was supported by the Canadian NSERC Grant No. OGP0121756 (P.V.) and by the Flemish Science Foundation (FWO-Vl) with a Ph.D. research grant (B.V.D.). ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
Call Number |
UA @ lucian @ c:irua:130264 |
Serial |
4247 |
Permanent link to this record |
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Author |
Missault, N.; Vasilopoulos, P.; Peeters, F.M.; Van Duppen, B. |
Title |
Spin- and valley-dependent miniband structure and transport in silicene superlattices |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
93 |
Issue |
93 |
Pages |
125425 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate silicene superlattices in the presence of a tunable barrier potential U, an exchange field M, and a perpendicular electric field E-z. The resulting miniband structure depends on the spin and valley indices and on the fields M and E-z. These fields determine the minigaps and also affect the additional Dirac points brought about by the periodic potential U. In addition, we consider diffusive transport and assess its dependence on the spin and valley indices as well as on temperature. The corresponding spin and valley polarizations strongly depend on the potential U and can be made almost 100% at very low temperatures at particular values of the Fermi energy. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000372715800009 |
Publication Date |
2016-03-21 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
49 |
Open Access |
|
Notes |
; This work was supported by the Canadian NSERC Grant No. OGP0121756 (P.V.), and by the Flemish Science Foundation FWO-Vl) with the “Odysseus” Program (N. M.) and with a PhD research grant (B.V.D.). ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:133194 |
Serial |
4246 |
Permanent link to this record |
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Author |
Sui, Y.; Jiang, Y.; Moretti, M.; Vlaeminck, S.E. |
Title |
Harvesting time and biomass composition affect the economics of microalgae production |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Journal Of Cleaner Production |
Abbreviated Journal |
J Clean Prod |
Volume |
259 |
Issue |
|
Pages |
120782-10 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL); Engineering Management (ENM) |
Abstract |
Cost simulations provide a strong tool to render the production of microalgae economically viable. This study evaluated the unexplored effect of harvesting time and the corresponding microalgal biomass composition on the overall production cost, under both continuous light and light/dark regime using techno-economic analysis (TEA). At the same time, the TEA gives evidence that a novel product “proteinaceous salt” from Dunaliella microalgae production is a promising high-value product for commercialization with profitability. The optimum production scenario is to employ natural light/dark regime and harvest microalgal biomass around late exponential phase, obtaining the minimum production cost of 11 €/kg and a profitable minimum selling price (MSP) of 14.4 €/kg for the “proteinaceous salt”. For further optimization of the production, increasing microalgal biomass concentration is the most effective way to reduce the total production cost and increase the profits of microalgae products. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000530695500009 |
Publication Date |
2020-02-29 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0959-6526 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
11.1 |
Times cited |
5 |
Open Access |
|
Notes |
; This work was supported by the China Scholarship Council (File No. 201507650015) and the MIP i-Cleantech Flanders (Milieu-innovatieplatform; Environment innovation platform) project Microbial Nutrients on Demand (MicroNOD). ; |
Approved |
Most recent IF: 11.1; 2020 IF: 5.715 |
Call Number |
UA @ admin @ c:irua:166802 |
Serial |
6531 |
Permanent link to this record |
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Author |
Xu, W.; Dong, H.M.; Li, L.L.; Yao, J.Q.; Vasilopoulos, P.; Peeters, F.M. |
Title |
Optoelectronic properties of graphene in the presence of optical phonon scattering |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
82 |
Issue |
12 |
Pages |
125304-125304,9 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study in detail the optoelectronic properties of graphene. Considering the electron interactions with photons and phonons, we employ the mass- and energy-balance equations to self-consistently evaluate the photoinduced carrier densities, the optical conductance, and the transmission coefficient in the presence of a linearly polarized radiation field. We demonstrate that the photoinduced carrier densities increase around the electron-photon-phonon resonant transition. They depend strongly on the radiation intensity and frequency, temperature, and dark carrier density. For short-wavelength radiation (L<3 μm), we obtain the universal optical conductance σ0=e2/(4ℏ). Importantly, there exists an optical-absorption window in the radiation wavelength range 4100 μm, which is induced by different transition energies required for interband and intraband optical absorption. The position and width of this window depend sensitively on the temperature and the carrier density of the system. These theoretical results are in line with recent experimental findings and indicate that graphene exhibits important features not only in the visible regime but also in the midinfrared bandwidth. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000281516500009 |
Publication Date |
2010-09-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
28 |
Open Access |
|
Notes |
; This work was supported by the Chinese Academy of Sciences, National Natural Science Foundation of China, and Department of Science and Technology of Yunnan Province. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:84260 |
Serial |
2496 |
Permanent link to this record |
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Author |
Kong, X.; Li, L.; Peeters, F.M. |
Title |
Topological Dirac semimetal phase in <tex> $GexSny alloys |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
112 |
Issue |
25 |
Pages |
251601 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Recently, two stable allotropes (germancite and stancite) for the group IV elements (Ge and Sn) with a staggered layered dumbell structure were proposed to be three-dimensional (3D) topological Dirac semimetals [Phys. Rev. B 93, 241117 (2016)]. A pair of Dirac points is on the rotation axis away from the time-reversal invariant momentum, and the stability of the 3D bulk Dirac points is protected by the C-3 rotation symmetry. Here, we use the first principles calculations to investigate GexSny alloys which share the same rhombohedral crystal structure with the space group of D-3d(6). Six GexSny alloys are predicted to be energetically and dynamically stable, where (x, y) = (8, 6) and (6, 8) and the alpha and beta phases of (10, 4) and (4, 10). Our results demonstrate that all the six GexSny alloys are topological Dirac semimetals. The different nontrivial surface states and surface Fermi arcs are identified. Our work will substantially enrich the family of 3D Dirac semimetals which are within the reach of experimental realization. Published by AIP Publishing. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000435987400013 |
Publication Date |
2018-06-18 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0003-6951; 1077-3118 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
8 |
Open Access |
|
Notes |
; This work was supported by the Collaborative Innovation Center of Quantum Matter, the Fonds voor Wetenschappelijk Onderzoek (FWO-VI), and the FLAG-ERA Project TRANS 2D TMD. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government – department EWI, and the National Supercomputing Center in Tianjin, funded by the Collaborative Innovation Center of Quantum Matter. ; |
Approved |
Most recent IF: 3.411 |
Call Number |
UA @ lucian @ c:irua:151970UA @ admin @ c:irua:151970 |
Serial |
5045 |
Permanent link to this record |
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Author |
Retuerto, M.; Calle-Vallejo, F.; Pascual, L.; Lumbeeck, G.; Fernandez-Diaz, M.T.; Croft, M.; Gopalakrishnan, J.; Pena, M.A.; Hadermann, J.; Greenblatt, M.; Rojas, S. |
Title |
La1.5Sr0.5NiMn0.5Ru0.5O6 double perovskite with enhanced ORR/OER bifunctional catalytic activity |
Type |
A1 Journal article |
Year |
2019 |
Publication |
ACS applied materials and interfaces |
Abbreviated Journal |
Acs Appl Mater Inter |
Volume |
11 |
Issue |
24 |
Pages |
21454-21464 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Perovskites (ABO(3)) with transition metals in active B sites are considered alternative catalysts for the water oxidation to oxygen through the oxygen evolution reaction (OER) and for the oxygen reduction through the oxygen reduction reaction (ORR) back to water. We have synthesized a double perovskite (A(2)BB'O-6) with different cations in A, B, and B' sites, namely, ((La15Sr0.5)-Sr-.)(A)(Ni0.5Mn0.5)(B)(Ni0.5Ru0.5)(B)O-6 (LSNMR), which displays an outstanding OER/ORR bifunctional performance. The composition and structure of the oxide has been determined by powder X-ray diffraction, powder neutron diffraction, and transmission electron microscopy to be monoclinic with the space group P2(1)/n and with cationic ordering between the ions in the B and B' sites. X-ray absorption near-edge spectroscopy suggests that LSNMR presents a configuration of similar to Ni2+, similar to Mn4+, and similar to Ru5+. This bifunctional catalyst is endowed with high ORR and OER activities in alkaline media, with a remarkable bifunctional index value of similar to 0.83 V (the difference between the potentials measured at -1 mA cm(-2) for the ORR and +10 mA cm(-2) for the OER). The ORR onset potential (E-onset) of 0.94 V is among the best reported to date in alkaline media for ORR-active perovskites. The ORR mass activity of LSNMR is 1.1 A g(-1) at 0.9 V and 7.3 A g(-1) at 0.8 V. Furthermore, LSNMR is stable in a wide potential window down to 0.05 V. The OER potential to achieve a current density of 10 mA cm(-2) is 1.66 V. Density functional theory calculations demonstrate that the high ORR/OER activity of LSNMR is related to the presence of active Mn sites for the ORR- and Ru-active sites for the OER by virtue of the high symmetry of the respective reaction steps on those sites. In addition, the material is stable to ORR cycling and also considerably stable to OER cycling. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000472683300019 |
Publication Date |
2019-05-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1944-8244 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.504 |
Times cited |
12 |
Open Access |
|
Notes |
; This work was supported by the ENE2016-77055-C3-3-R project from the Spanish Ministry of Economy and Competitiveness (MINECO) and PIE 201480E122 from CSIC. M.R. thanks MINECO's Juan de la Cierva program for a grant (FPDI-2013-17582). F.C.-V. thanks the Spanish MEC for a Ramon y Cajal research contract (RYC-2015-18996). M.G. acknowledges the support from NSF-DMR-1507252 grant, NJ, USA. ; |
Approved |
Most recent IF: 7.504 |
Call Number |
UA @ admin @ c:irua:161320 |
Serial |
5400 |
Permanent link to this record |
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Author |
Müller, A.; Milošević, M.V.; Dale, S.E.C.; Engbarth, M.A.; Bending, S.J. |
Title |
Magnetization measurements and Ginzburg-Landau simulations of micron-size \beta-tin samples : evidence for an unusual critical behavior of mesoscopic type-I superconductors |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
Volume |
109 |
Issue |
19 |
Pages |
197003 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We describe investigations of the largely unexplored field of mesoscopic type-I superconductors. Micromagnetometry and 3D Ginzburg-Landau simulations of our single crystal β-tin samples in this regime reveal size- and temperature-dependent supercritical fields whose behavior is radically different from the bulk critical field HcB. We find that complete suppression of the intermediate state in medium-size samples can result in a surprising reduction of the critical field significantly below HcB. We also reveal an evolution of the superconducting-to-normal phase transition from the expected irreversible first order at low temperatures through the previously unobserved reversible first-order to a second-order transition close to Tc, where the critical field can be many times larger than HcB. Finally, we have identified striking correlations between the mesoscopic Hc3 for nucleation of surface superconductivity and the thermodynamic Hc near Tc. All these observations are entirely unexpected in the conventional type-I picture. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000310853100017 |
Publication Date |
2012-11-09 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.462 |
Times cited |
21 |
Open Access |
|
Notes |
; This work was supported by the EPSRC-UK under Grant No. EP/E039944/1, and the Flemish Science Foundation (FWO). ; |
Approved |
Most recent IF: 8.462; 2012 IF: 7.943 |
Call Number |
UA @ lucian @ c:irua:102401 |
Serial |
1893 |
Permanent link to this record |
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Author |
Malkov, I., V; Krivetskii, V.V.; Potemkin, D., I; Zadesenets, A., V; Batuk, M.M.; Hadermann, J.; Marikutsa, A., V; Rumyantseva, M.N.; Gas'kov, A.M. |
Title |
Effect of Bimetallic Pd/Pt Clusters on the Sensing Properties of Nanocrystalline SnO2 in the Detection of CO |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Russian journal of inorganic chemistry |
Abbreviated Journal |
Russ J Inorg Chem+ |
Volume |
63 |
Issue |
8 |
Pages |
1007-1011 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Nanocrystalline tin dioxide modified by Pd and Pt clusters or by bimetallic PdPt nanoparticles was synthesized. Distribution of the modifers on the SnO2 surface was studied by high-resolution transmission electron microscopy and energy dispersive X-ray microanalysis with element distribution mapping. It was shown that the Pd/Pt ratio in bimetallic particles varies over a broad range and does not depend on the particle diameter. The effect of platinum metals on the reducibility of nanocrystalline SnO2 by hydrogen was determined. The sensing properties of the resulting materials towards 6.7 ppm CO in air were estimated in situ by electrical conductivity measurements. The sensor response of SnO2 modified with bimetallic PdPt particles was a superposition of the signals of samples with Pt and Pd clusters. |
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 |
000442749500003 |
Publication Date |
2018-08-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0036-0236 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.787 |
Times cited |
3 |
Open Access |
Not_Open_Access |
Notes |
; This work was supported by the ERA.Net RUS Plus program (project 096 FONSENS, RFBR grant 16-53-76001). ; |
Approved |
Most recent IF: 0.787 |
Call Number |
UA @ lucian @ c:irua:153752 |
Serial |
5092 |
Permanent link to this record |
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|
Author |
Zhang, S.H.; Xu, W.; Badalyan, S.M.; Peeters, F.M. |
Title |
Piezoelectric surface acoustical phonon limited mobility of electrons in graphene on a GaAs substrate |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
87 |
Issue |
7 |
Pages |
075443-75445 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study the mobility of Dirac fermions in monolayer graphene on a GaAs substrate, limited by the combined action of the extrinsic potential of piezoelectric surface acoustical phonons of GaAs (PA) and of the intrinsic deformation potential of acoustical phonons in graphene (DA). In the high-temperature (T) regime, the momentum relaxation rate exhibits the same linear dependence on T but different dependencies on the carrier density n, corresponding to the mobility mu proportional to 1 root n and 1/n, respectively for the PA and DA scattering mechanisms. In the low-T Bloch-Gruneisen regime, the mobility shows the same square-root density dependence mu proportional to root n, but different temperature dependencies mu proportional to T-3 and T-4, respectively for PA and DA phonon scattering. DOI: 10.1103/PhysRevB.87.075443 |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000315375200008 |
Publication Date |
2013-02-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
25 |
Open Access |
|
Notes |
; This work was supported by the ESF-Eurocores program EuroGRAPHENE (CONGRAN project) and the Flemish Science Foundation (FWO-VI). ; |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
Call Number |
UA @ lucian @ c:irua:107655 |
Serial |
2622 |
Permanent link to this record |
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|
|
Author |
Zhu, J.-J.; Badalyan, S.M.; Peeters, F.M. |
Title |
Plasmonic excitations in Coulomb-coupled N-layer graphene structures |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
87 |
Issue |
8 |
Pages |
085401-85408 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study Dirac plasmons and their damping in spatially separated N-layer graphene structures at finite doping and temperatures. The plasmon spectrum consists of one optical excitation with square-root dispersion and N – 1 acoustical excitations with linear dispersion, which are undamped at zero temperature and finite doping within a triangular energy region outside the electron-hole continuum. In the long-wavelength limit the energy and weight of the optical plasmon modes increase, respectively, as the square root and linearly with N in agreement with recent experimental findings. The energy and weight of the upper-lying acoustical branches also increase with N. This increase is strongest for the uppermost acoustical mode, and we find that its energy can exceed at some value of momentum the plasmon energy in an individual graphene sheet. Meanwhile, the energy of the low-lying acoustical branches decreases weakly with N as compared with the single acoustical mode in double-layer graphene structures. Our numerical calculations provide a detailed understanding of the overall behavior of the wave-vector dependence of the optical and acoustical multilayer plasmon modes and show how their dispersion and damping are modified as a function of temperature, interlayer spacing, and inlayer carrier density in (un)balanced graphene multilayer structures. DOI: 10.1103/PhysRevB.87.085401 |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000314682900005 |
Publication Date |
2013-02-05 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
59 |
Open Access |
|
Notes |
; This work was supported by the ESF-Eurocores program EuroGRAPHENE (CONGRAN project) and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
Call Number |
UA @ lucian @ c:irua:107671 |
Serial |
2645 |
Permanent link to this record |
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|
|
Author |
Sobrino Fernandez, M.M.; Neek-Amal, M.; Peeters, F.M. |
Title |
AA-stacked bilayer square ice between graphene layers |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
92 |
Issue |
92 |
Pages |
245428 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Water confined between two graphene layers with a separation of a few A forms a layered two-dimensional ice structure. Using large scale molecular dynamics simulations with the adoptable ReaxFF interatomic potential we found that flat monolayer ice with a rhombic-square structure nucleates between the graphene layers which is nonpolar and nonferroelectric. We provide different energetic considerations and H-bonding results that explain the interlayer and intralayer properties of two-dimensional ice. The controversial AA stacking found experimentally [Algara-Siller et al., Nature (London) 519, 443 (2015)] is consistent with our minimum-energy crystal structure of bilayer ice. Furthermore, we predict that an odd number of layers of ice has the same lattice structure as monolayer ice, while an even number of ice layers exhibits the square ice AA stacking of bilayer ice. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000366731800004 |
Publication Date |
2015-12-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121; 1550-235x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
40 |
Open Access |
|
Notes |
; This work was supported by the ESF-Eurographene project CONGRAN, and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
Call Number |
c:irua:130203 |
Serial |
4127 |
Permanent link to this record |
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|
|
Author |
Ghorbanfekr-Kalashami, H.; Neek-Amal, M.; Peeters, F.M. |
Title |
N-doped graphene : polarization effects and structural properties |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
93 |
Issue |
93 |
Pages |
174112 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The structural and mechanical properties of N-doped graphene (NG) are investigated using reactive force field (ReaxFF) potentials in large-scale molecular dynamics simulations. We found that ripples, which are induced by the dopants, change the roughness of NG, which depends on the number of dopants and their local arrangement. For any doping ratio N/C, the NG becomes ferroelectric with a net dipole moment. The formation energy increases nonlinearly with N/C ratio, while the Young's modulus, tensile strength, and intrinsic strain decrease with the number of dopants. Our results for the structural deformation and the thermoelectricity of the NG sheet are in good agreement with recent experiments and ab initio calculations. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000376245900002 |
Publication Date |
2016-05-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
15 |
Open Access |
|
Notes |
; This work was supported by the ESF-Eurographene project CONGRAN, and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:134148 |
Serial |
4212 |
Permanent link to this record |
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|
|
Author |
Arsoski, V.; Čukarić, N.; Tadić, M.; Peeters, F.M. |
Title |
Exciton states in a nanocup in the presence of a perpendicular magnetic field |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physica scripta |
Abbreviated Journal |
Phys Scripta |
Volume |
T149 |
Issue |
|
Pages |
014054-014054,5 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The exciton states in a strained (In,Ga)As/GaAs nanocup are theoretically determined. We explore how the nanocup bottom thickness (t) affects the magnetic field dependence of the exciton energy. Strain distribution is computed by the continuum mechanical model under the approximation of isotropic elasticity. The exciton wave functions are expanded into products of the electron and hole envelope functions. For small t, the exciton ground state has zero orbital momentum and exhibits small oscillations of the second derivative when the magnetic field increases. When t approaches the value of the cup height, however, the exciton levels exhibit angular momentum transitions, whose behavior is similar to that for type-II quantum dots. Small oscillations of the oscillator strength for exciton recombination are found when the magnetic field increases. An increase in thickness of the nanocup bottom has only a small effect on those oscillations for the optically active exciton states, but the exciton ground state becomes dark when the magnetic field increases. Hence, the results of our calculations show that an increase in thickness of the nanocup bottom transforms the exciton ground energy level dependence on magnetic field from the one characteristic of type-I rings to the one characteristic of type-II dots. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Stockholm |
Editor |
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Language |
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Wos |
000303523500055 |
Publication Date |
2012-04-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0031-8949;1402-4896; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.28 |
Times cited |
2 |
Open Access |
|
Notes |
; This work was supported by the EU Network of Excellence SANDiE, the Ministry of Education and Science of Serbia, the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 1.28; 2012 IF: 1.032 |
Call Number |
UA @ lucian @ c:irua:99135 |
Serial |
1117 |
Permanent link to this record |
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|
|
Author |
Arsoski, V.; Tadic, M.; Peeters, F.M. |
Title |
Electric field tuning of the optical excitonic Aharonov-Bohm effect in nanodots grown by droplet epitaxy |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physica scripta |
Abbreviated Journal |
Phys Scripta |
Volume |
T157 |
Issue |
|
Pages |
014002 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Neutral excitons in axially symmetric GaAs nanodots embedded in an (Al, Ga) As matrix, which are formed by the droplet epitaxy technique, are investigated theoretically. An electric field perpendicular to the nanodot base results in both a vertical and an in-plane exciton polarization, which is beneficial for the appearance of the excitonic Aharonov-Bohm effect. In the range of low magnetic fields (below 5 Tesla), we found that the bright and dark exciton states can cross twice. This results in oscillations of the photoluminescence intensity with magnetic field, which are a striking manifestation of the optical excitonic Aharonov-Bohm effect. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Stockholm |
Editor |
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Language |
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Wos |
000332504600003 |
Publication Date |
2013-11-15 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0031-8949 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
1.28 |
Times cited |
|
Open Access |
|
Notes |
; This work was supported by the EU Network of Excellence: SANDiE, the Ministry of Education and Science of Serbia, the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 1.28; 2013 IF: 1.296 |
Call Number |
UA @ lucian @ c:irua:128901 |
Serial |
4594 |
Permanent link to this record |
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|
|
Author |
Arsoski, V.V.; Tadić, M.Z.; Peeters, F.M. |
Title |
Strain and band-mixing effects on the excitonic Aharonov-Bohm effect in In(Ga)As/GaAs ringlike quantum dots |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
87 |
Issue |
8 |
Pages |
085314-14 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Neutral excitons in strained axially symmetric In(Ga)As/GaAs quantum dots with a ringlike shape are investigated. Similar to experimental self-assembled quantum rings, the analyzed quantum dots have volcano-like shapes. The continuum mechanical model is employed to determine the strain distribution, and the single-band envelope function approach is adopted to compute the electron states. The hole states are determined by the axially symmetric multiband Luttinger-Kohn Hamiltonian, and the exciton states are obtained from an exact diagonalization. We found that the presence of the inner layer covering the ring opening enhances the excitonic Aharonov-Bohm (AB) oscillations. The reason is that the hole becomes mainly localized in the inner part of the quantum dot due to strain, whereas the electron resides mainly inside the ring-shaped rim. Interestingly, larger AB oscillations are found in the analyzed quantum dot than in a fully opened quantum ring of the same width. Comparison with the unstrained ringlike quantum dot shows that the amplitude of the excitonic Aharonov-Bohm oscillations are almost doubled in the presence of strain. The computed oscillations of the exciton energy levels are comparable in magnitude to the oscillations measured in recent experiments. DOI: 10.1103/PhysRevB.87.085314 |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000315278000003 |
Publication Date |
2013-02-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
18 |
Open Access |
|
Notes |
; This work was supported by the EU NoE: SANDiE, the Ministry of Education, Science, and Technological Development of Serbia, and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
Call Number |
UA @ lucian @ c:irua:107656 |
Serial |
3165 |
Permanent link to this record |
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Author |
Seyed-Talebi, S.M.; Beheshtian, J.; Neek-Amal, M. |
Title |
Doping effect on the adsorption of NH3 molecule onto graphene quantum dot : from the physisorption to the chemisorption |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
114 |
Issue |
12 |
Pages |
124307-7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The adsorption of ammonia molecule onto a graphene hexagonal flake, aluminum (Al) and boron (B) doped graphene flakes (graphene quantum dots, GQDs) are investigated using density functional theory. We found that NH3 molecule is absorbed to the hollow site through the physisorption mechanism without altering the electronic properties of GQD. However, the adsorption energy of NH3 molecule onto the Al- and B-doped GQDs increases with respect GQD resulting chemisorption. The adsorption of NH3 onto the Al-doped and B-doped GQDs makes graphene locally buckled, i.e., B-doped and Al-doped GQDs are not planar. The adsorption mechanism onto a GQD is different than that of graphene. This study reveals important features of the edge passivation and doping effects of the adsorption mechanism of external molecules onto the graphene quantum dots. (C) 2013 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000325391100057 |
Publication Date |
2013-09-26 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
10 |
Open Access |
|
Notes |
; This work was supported by the EU-Marie Curie IIF Fellowship/299855 for M.-N.A. ; |
Approved |
Most recent IF: 2.068; 2013 IF: 2.185 |
Call Number |
UA @ lucian @ c:irua:112201 |
Serial |
750 |
Permanent link to this record |
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Author |
Neek-Amal, M.; Beheshtian, J.; Sadeghi, A.; Michel, K.H.; Peeters, F.M. |
Title |
Boron nitride mono layer : a strain-tunable nanosensor |
Type |
A1 Journal article |
Year |
2013 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
Volume |
117 |
Issue |
25 |
Pages |
13261-13267 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
The influence of triaxial in-plane strain on the electronic properties of a hexagonal boron-nitride sheet is investigated using density functional theory. Different from graphene, the triaxial strain localizes the molecular orbitals of the boron-nitride flake in its center depending on the direction of the applied strain. The proposed technique for localizing the molecular orbitals that are close to the Fermi level in the center of boron nitride flakes can be used to actualize engineered nanosensors, for instance, to selectively detect gas molecules. We show that the central part of the strained flake adsorbs polar molecules more strongly as compared with an unstrained sheet. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000321236400041 |
Publication Date |
2013-06-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.536 |
Times cited |
38 |
Open Access |
|
Notes |
; This work was supported by the EU-Marie Curie IIF postdoc Fellowship/299855 (for M.N.-A.), the ESF EuroGRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-VI), and the Methusalem Funding of the Flemish government. AS. would like to thank the Universiteit Antwerpen for its hospitality. ; |
Approved |
Most recent IF: 4.536; 2013 IF: 4.835 |
Call Number |
UA @ lucian @ c:irua:109829 |
Serial |
249 |
Permanent link to this record |
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Author |
Singh, S.K.; Costamagna, S.; Neek-Amal, M.; Peeters, F.M. |
Title |
Melting of partially fluorinated graphene : from detachment of fluorine atoms to large defects and random coils |
Type |
A1 Journal article |
Year |
2014 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
Volume |
118 |
Issue |
8 |
Pages |
4460-4464 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
The melting of fluorographene is very unusual and depends strongly on the degree of fluorination. For temperatures below 1000 K, fully fluorinated graphene (FFG) is thermomechanically more stable than graphene but at T-m approximate to 2800 K FFG transits to random coils which is almost 2 times lower than the melting temperature of graphene, i.e., 5300 K. For fluorinated graphene up to 30% ripples causes detachment of individual F-atoms around 2000 K, while for 40%-60% fluorination large defects are formed beyond 1500 K and beyond 60% of fluorination F-atoms remain bonded to graphene until melting. The results agree with recent experiments on the dependence of the reversibility of the fluorination process on the percentage of fluorination. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington, D.C. |
Editor |
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Language |
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Wos |
000332188100069 |
Publication Date |
2014-01-22 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1932-7447; 1932-7455 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.536 |
Times cited |
16 |
Open Access |
|
Notes |
; This work was supported by the EU-Marie Curie IIF postdoc Fellowship/299855 (for M.N.-A.), the ESF-Eurographene project CONGRAN, and the Flemish Science Foundation (FWO-VI). Financial support from the Collaborative program MINCyT (Argentina)-FWO(Belgium) is also acknowledged. ; |
Approved |
Most recent IF: 4.536; 2014 IF: 4.772 |
Call Number |
UA @ lucian @ c:irua:128874 |
Serial |
4600 |
Permanent link to this record |
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Author |
Singh, S.K.; Neek-Amal, M.; Peeters, F.M. |
Title |
Melting of graphene clusters |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
87 |
Issue |
13 |
Pages |
134103-134109 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Density-functional tight-binding and classical molecular dynamics simulations are used to investigate the structural deformations and melting of planar carbon nanoclusters C-N with N = 2-55. The minimum-energy configurations for different clusters are used as starting configurations for the study of the temperature effects on the bond breaking and rotation in carbon lines (N < 6), carbon rings (5 < N < 19), and graphene nanoflakes. The larger the rings (graphene nanoflakes) the higher the transition temperature (melting point) with ring-to-line (perfect-to-defective) transition structures. The melting point was obtained by using the bond energy, the Lindemann criteria, and the specific heat. We found that hydrogen-passivated graphene nanoflakes (CNHM) have a larger melting temperature with a much smaller dependence on size. The edges in the graphene nanoflakes exhibit several different metastable configurations (isomers) during heating before melting occurs. DOI: 10.1103/PhysRevB.87.134103 |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000317390700001 |
Publication Date |
2013-04-11 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
28 |
Open Access |
|
Notes |
; This work was supported by the EU-Marie Curie IIF Postdoctoral Fellowship No. 299855 (for M.N.-A.), the ESF-EuroGRAPHENE Project CONGRAN, the Flemish Science Foundation (FWO-Vl), and the Methusalem Foundation of the Flemish Government. ; |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
Call Number |
UA @ lucian @ c:irua:108467 |
Serial |
1987 |
Permanent link to this record |
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|
Author |
Singh, S.K.; Neek-Amal, M.; Peeters, F.M. |
Title |
Electronic properties of graphene nano-flakes : energy gap, permanent dipole, termination effect, and Raman spectroscopy |
Type |
A1 Journal article |
Year |
2014 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
Volume |
140 |
Issue |
7 |
Pages |
074304-74309 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The electronic properties of graphene nano-flakes (GNFs) with different edge passivation are investigated by using density functional theory. Passivation with F and H atoms is considered: C-Nc X-Nx (X = F or H). We studied GNFs with 10 < N-c < 56 and limit ourselves to the lowest energy configurations. We found that: (i) the energy difference Delta between the highest occupied molecular orbital and the lowest unoccupied molecular orbital decreases with N-c, (ii) topological defects (pentagon and heptagon) break the symmetry of the GNFs and enhance the electric polarization, (iii) the mutual interaction of bilayer GNFs can be understood by dipole-dipole interaction which were found sensitive to the relative orientation of the GNFs, (iv) the permanent dipoles depend on the edge terminated atom, while the energy gap is independent of it, and (v) the presence of heptagon and pentagon defects in the GNFs results in the largest difference between the energy of the spin-up and spin-down electrons which is larger for the H-passivated GNFs as compared to F-passivated GNFs. Our study shows clearly the effect of geometry, size, termination, and bilayer on the electronic properties of small GNFs. This study reveals important features of graphene nano-flakes which can be detected using Raman spectroscopy. (C) 2014 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000332039900020 |
Publication Date |
2014-02-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-9606;1089-7690; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.965 |
Times cited |
30 |
Open Access |
|
Notes |
; This work was supported by the EU-Marie Curie IIF postdoctoral Fellowship/ 299855 (for M. N.-A.), the ESF-EuroGRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-Vl), and the Methusalem Foundation of the Flemish Government. ; |
Approved |
Most recent IF: 2.965; 2014 IF: 2.952 |
Call Number |
UA @ lucian @ c:irua:115857 |
Serial |
1002 |
Permanent link to this record |
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|
|
Author |
Neek-Amal, M.; Covaci, L.; Shakouri, K.; Peeters, F.M. |
Title |
Electronic structure of a hexagonal graphene flake subjected to triaxial stress |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
88 |
Issue |
11 |
Pages |
115428 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The electronic properties of a triaxially strained hexagonal graphene flake with either armchair or zigzag edges are investigated using molecular dynamics simulations and tight-binding calculations. We found that (i) the pseudomagnetic field in strained graphene flakes is not uniform neither in the center nor at the edge of zigzag terminated flakes, (ii) the pseudomagnetic field is almost zero in the center of armchair terminated flakes but increases dramatically near the edges, (iii) the pseudomagnetic field increases linearly with strain, for strains lower than 15% but increases nonlinearly beyond it, (iv) the local density of states in the center of the zigzag hexagon exhibits pseudo-Landau levels with broken sublattice symmetry in the zeroth pseudo-Landau level, and in addition there is a shift in the Dirac cone due to strain induced scalar potentials, and (v) there is size effect in pseudomagnetic field. This study provides a realistic model of the electronic properties of inhomogeneously strained graphene where the relaxation of the atomic positions is correctly included together with strain induced modifications of the hopping terms up to next-nearest neighbors. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000324690400008 |
Publication Date |
2013-09-24 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
46 |
Open Access |
|
Notes |
; This work was supported by the EU-Marie Curie IIF postdoctoral Fellowship/ 299855 (for M.N.-A.), the ESF EuroGRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-Vl) and the Methusalem Funding of the Flemish government. ; |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
Call Number |
UA @ lucian @ c:irua:111168 |
Serial |
1011 |
Permanent link to this record |
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|
|
Author |
Li, B.; Peeters, F.M. |
Title |
Tunable optical Aharonov-Bohm effect in a semiconductor quantum ring |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
83 |
Issue |
11 |
Pages |
115448-115448,13 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
By applying an electric field perpendicular to a semiconductor quantum ring we show that it is possible to modify the single particle wave function between quantum dot (QD)-like and ring-like. The constraints on the geometrical parameters of the quantum ring to realize such a transition are derived. With such a perpendicular electric field we are able to tune the Aharanov-Bohm (AB) effect for both the single particle and for excitons. The tunability is in both the strength of the AB effect as well as in its periodicity. We also investigate the strain induce potential inside the self-assembled quantum ring and the effect of the strain on the AB effect. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000288855200012 |
Publication Date |
2011-03-28 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
25 |
Open Access |
|
Notes |
; This work was supported by the EU-NoE: SANDiE, the Flemish Science Foundation (FWO-Vl), the Interuniversity Attraction Poles, Belgium State, Belgium Science Policy, and IMEC, vzw collaborative project. We are grateful to Prof. M. Tadic and Dr. Fei Ding for stimulating discussions. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:89376 |
Serial |
3744 |
Permanent link to this record |
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Author |
Grujić, M.; Zarenia, M.; Tadić, M.; Peeters, F.M. |
Title |
Interband optical absorption in a circular graphene quantum dot |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physica scripta |
Abbreviated Journal |
Phys Scripta |
Volume |
T149 |
Issue |
|
Pages |
014056-014056,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate the energy levels and optical properties of a circular graphene quantum dot in the presence of an external magnetic field perpendicular to the dot. Based on the Dirac-Weyl equation and assuming zero outward current at the edge of the dot we present the results for two different types of boundary conditions, i.e. infinite-mass (IMBC) and zigzag boundary conditions. We found that the dot with zigzag edges displays a zero-energy state in the energy spectra while this is not the case for the IMBCs. For both boundary conditions, the confinement becomes dominated by the magnetic field, where the energy levels converge to the Landau levels as the magnetic field increases. The effect of boundary conditions on the electron-and hole-energy states is found to affect the interband absorption spectra, where we found larger absorption in the case of IMBCs. The selection rules for interband optical transitions are determined and discussed for both boundary conditions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Stockholm |
Editor |
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Language |
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Wos |
000303523500057 |
Publication Date |
2012-04-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0031-8949;1402-4896; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.28 |
Times cited |
5 |
Open Access |
|
Notes |
; This work was supported by the EuroGraphene program of the ESF (project CONGRAN), the Ministry of Education and Science of Serbia, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 1.28; 2012 IF: 1.032 |
Call Number |
UA @ lucian @ c:irua:99136 |
Serial |
1688 |
Permanent link to this record |
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Author |
Grujić, M.; Zarenia, M.; Chaves, A.; Tadić, M.; Farias, G.A.; Peeters, F.M. |
Title |
Electronic and optical properties of a circular graphene quantum dot in a magnetic field : influence of the boundary conditions |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
84 |
Issue |
20 |
Pages |
205441-205441,12 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
An analytical approach, using the Dirac-Weyl equation, is implemented to obtain the energy spectrum and optical absorption of a circular graphene quantum dot in the presence of an external magnetic field. Results are obtained for the infinite-massand zigzag boundary conditions. We found that the energy spectrum of a dot with the zigzag boundary condition exhibits a zero-energy band regardless of the value of the magnetic field, while for the infinite-mass boundary condition, the zero-energy states appear only for high magnetic fields. The analytical results are compared to those obtained from the tight-binding model: (i) we show the validity range of the continuum model and (ii) we find that the continuum model with the infinite-mass boundary condition describes rather well its tight-binding analog, which can be partially attributed to the blurring of the mixed edges by the staggered potential. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000297295400011 |
Publication Date |
2011-11-21 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
78 |
Open Access |
|
Notes |
; This work was supported by the EuroGraphene programme of the ESF (project CONGRAN), the Ministry of Education and Science of Serbia, the Belgian Science Policy (IAP), the bilateral projects between Flanders and Brazil, the Flemish Science Foundation (FWO-Vl), and the Brazilian Research Council (CNPq). ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:94025 |
Serial |
997 |
Permanent link to this record |
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Author |
Grujić, M.; Tadić, M.; Peeters, F.M. |
Title |
Antiferromagnetism in hexagonal graphene structures : rings versus dots |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
87 |
Issue |
8 |
Pages |
085434-85436 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Themean-field Hubbard model is used to investigate the formation of the antiferromagnetic phase in hexagonal graphene rings with inner zigzag edges. The outer edge of the ring was taken to be either zigzag or armchair, and we found that both types of structures can have a larger antiferromagnetic interaction as compared with hexagonal dots. This difference could be partially ascribed to the larger number of zigzag edges per unit area in rings than in dots. Furthermore, edge states localized on the inner ring edge are found to hybridize differently than the edge states of dots, which results in important differences in the magnetism of graphene rings and dots. The largest staggered magnetization is found when the outer edge has a zigzag shape. However, narrow rings with armchair outer edge are found to have larger staggered magnetization than zigzag hexagons. The edge defects are shown to have the least effect on magnetization when the outer ring edge is armchair shaped. DOI: 10.1103/PhysRevB.87.085434 |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000315146600005 |
Publication Date |
2013-02-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
29 |
Open Access |
|
Notes |
; This work was supported by the EuroGRAPHENE programme of the ESF (project CONGRAN), the Serbian Ministry of Education, Science, and Technological Development, and the Flemish Science Foundation (FWO-VI). ; |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
Call Number |
UA @ lucian @ c:irua:107661 |
Serial |
137 |
Permanent link to this record |
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Author |
Croitoru, M.D.; Shanenko, A.A.; Peeters, F.M.; Axt, V.M. |
Title |
Parity-fluctuation induced enlargement of the ratio \DeltaE/kBTc in metallic grains |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
84 |
Issue |
21 |
Pages |
214518-214518,12 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate how the interplay of quantum confinement and particle number-parity fluctuations affects superconducting correlations in ultra-small metallic grains. Using the number-parity projected BCS formalism we calculate the critical temperature and the excitation gap as a function of the grain size for grains with even and odd number of confined carriers. We show that the experimentally observed anomalous increase of the coupling ratio ΔE/kBTc with decreasing superconducting grain size can be attributed to an enhancement of the number-parity fluctuations in ultra-small grains. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000298114100003 |
Publication Date |
2011-12-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
14 |
Open Access |
|
Notes |
; This work was supported by the European Community under a Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR), the Flamish Science Foundation (FWO-Vl), and the Belgian Science Policy (IAP). M. D. C. thanks A. S. Mel'nikov and N. B. Kopnin for fruitful discussions. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:94373 |
Serial |
2555 |
Permanent link to this record |
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Author |
Croitoru, M.D.; Shanenko, A.A.; Kaun, C.C.; Peeters, F.M. |
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) |
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. |
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 |
000305653100012 |
Publication Date |
2012-06-21 |
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 |
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 |
Call Number |
UA @ lucian @ c:irua:100280 |
Serial |
3793 |
Permanent link to this record |