Records |
Author |
Kerner, C.; Hackens, B.; Golubović, D.S.; Poli, S.; Faniel, S.; Magnus, W.; Schoenmaker, W.; Bayot, V.; Maes, H. |
Title |
Control and readout of current-induced magnetic flux quantization in a superconducting transformer |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
Volume |
22 |
Issue |
2 |
Pages |
025001,1-025001,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We demonstrate a simple and robust method for inducing and detecting changes of magnetic flux quantization in the absence of an externally applied magnetic field. In our device, an isolated ring is interconnected with two access loops via permalloy cores, forming a superconducting transformer. By applying and tuning a direct current at the first access loop, the number of flux quanta trapped in the isolated ring is modified without the aid of an external field. The flux state of the isolated ring is simply detected by recording the evolution of the critical current of the second access loop. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000262786000003 |
Publication Date |
2008-12-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-2048;1361-6668; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.878 |
Times cited |
2 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.878; 2009 IF: 2.694 |
Call Number |
UA @ lucian @ c:irua:76001 |
Serial |
497 |
Permanent link to this record |
|
|
|
Author |
Abakumov, A.M.; King, G.; Laurinavichute, V.K.; Rozova, M.G.; Woodward, P.M.; Antipov, E.V. |
Title |
The crystal structure of \alpha-K3AIF6: elpasolites and double perovskites with broken corner-sharing connectivity of the octahedral framework |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
Volume |
48 |
Issue |
19 |
Pages |
9336-9344 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The crystal structure of α-K3AlF6 was solved and refined from a combination of powder X-ray and neutron diffraction data (a = 18.8385(3)Å, c = 33.9644(6)Å, S.G. I41/a, Z = 80, RP(X-ray) = 0.037, RP(neutron) = 0.053). The crystal structure is of the A2BB′X6 elpasolite type with the a = b ≈ ae√5, c = 4ae superstructure (ae, parameter of the elpasolite subcell) and rock-salt-type ordering of the K and Al cations over the B and B′ positions, respectively. The remarkable feature of α-K3AlF6 is a rotation of 2/5 of the AlF6 octahedra by π/4 around one of the crystal axes of the elpasolite subcell, coinciding with the 4-fold symmetry axes of the AlF6 octahedra. The rotation of the AlF6 octahedra replaces the corner-sharing between the K and Al polyhedra by edge-sharing, resulting in an increase of coordination numbers of the K cations at the B positions up to 7 and 8. Due to significant deformations of the K polyhedra, the corner-sharing connectivity of the octahedral elpasolite framework is broken and the rotations of the AlF6 octahedra do not have a cooperative character. Elpasolites and double perovskites with similar structural organization are discussed. The difference in ionic radii of the B and B′ cations as well as the tolerance factor are proposed to be the parameters governing the formation of elpasolites and double perovskites with broken corner-sharing connectivity of the octahedral framework. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Easton, Pa |
Editor |
|
Language |
|
Wos |
000270091000039 |
Publication Date |
2009-09-03 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0020-1669;1520-510X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.857 |
Times cited |
20 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.857; 2009 IF: 4.657 |
Call Number |
UA @ lucian @ c:irua:79733 |
Serial |
568 |
Permanent link to this record |
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|
|
Author |
Tarakina, N.V.; Zubkov, V.G.; Leonidov, I.I.; Tyutunnik, A.P.; Surat, L.L.; Hadermann, J.; Van Tendeloo, G. |
Title |
Crystal structure of the group of optical materials Ln2MeGe4O12 (Me = Ca, Mn) |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Zeitschrift für Kristallographie |
Abbreviated Journal |
|
Volume |
|
Issue |
S:30 |
Pages |
401-406 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The crystal structure of the group of optical materials Ln2MeGe4O12, Ln = Eu, Gd, Dy-Lu, Y; Me = Ca, Mn and of the solid solution (Y1-xErx)2CaGe4O12 (x = 0 – 1), promising materials for photonics, has been studied in detail. The crystal structure of all compounds exhibit two alternating layers: one formed by Ln and Me atoms and another by cyclic [Ge4O12]8- anions. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
München |
Editor |
|
Language |
|
Wos |
000271325700028 |
Publication Date |
2009-08-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0930-486X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
7 |
Open Access |
|
Notes |
Iap |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:79988 |
Serial |
575 |
Permanent link to this record |
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|
|
Author |
Wang, M.; Chang, K.; Wang, L.G.; Dai, N.; Peeters, F.M. |
Title |
Crystallographic plane tuning of charge and spin transport in semiconductor quantum wires |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
Volume |
20 |
Issue |
36 |
Pages |
365202,1-365202,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate theoretically the charge and spin transport in quantum wires grown along different crystallographic planes in the presence of the Rashba spinorbit interaction (RSOI) and the Dresselhaus spinorbit interaction (DSOI). We find that changing the crystallographic planes leads to a variation of the anisotropy of the conductance due to a different interplay between the RSOI and DSOI, since the DSOI is induced by bulk inversion asymmetry, which is determined by crystallographic plane. This interplay depends sensitively on the crystallographic planes, and consequently leads to the anisotropic charge and spin transport in quantum wires embedded in different crystallographic planes. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000269077000003 |
Publication Date |
2009-08-19 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.44 |
Times cited |
14 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.44; 2009 IF: 3.137 |
Call Number |
UA @ lucian @ c:irua:78933 |
Serial |
588 |
Permanent link to this record |
|
|
|
Author |
Barreca, D.; Gasparotto, A.; Maccato, C.; Tondello, E.; Lebedev, O.I.; Van Tendeloo, G. |
Title |
CVD of copper oxides from a \beta-diketonate diamine precursor: tailoring the nano-organization |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
Volume |
9 |
Issue |
5 |
Pages |
2470-2480 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A copper(II) hexafluoroacetylacetonate (1,1,1,5,5,5-hexafluoro-2,4-pentanedionate, hfa) adduct with N,N,N¡ä,N¡ä-tetramethylethylenediamine (TMEDA) [Cu(hfa)2¡¤TMEDA] is used for the first time as precursor for the chemical vapor deposition (CVD) of copper oxide nanosystems. The syntheses are carried out under both O2 and O2+H2O reaction atmospheres on Si(100) substrates, at temperatures ranging between 250 and 550 ¡ãC. Subsequently, the interrelations between the preparative conditions and the system composition, nanostructure, and morphology are elucidated by means of complementary analytical techniques [Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron and X-ray excited auger electron spectroscopies (XPS and XE-AES), glancing incidence X-ray diffraction (GIXRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM)]. The obtained data revealed a gradual transformation from Cu2O, to Cu2O + CuO, to CuO nanosystems upon increasing the deposition temperature from 250 to 550 ¡ãC under both growth atmospheres. Such a phenomenon was accompanied by a progressive morphological evolution from continuous films to 1D hyperbranched nanostructures. Water vapor introduction in the deposition environment enabled to lower the deposition temperature and resulted in a higher aggregate interconnection, attributed to a higher density of nucleation centers. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
|
Language |
|
Wos |
000265892200066 |
Publication Date |
2009-05-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1528-7483;1528-7505; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.055 |
Times cited |
60 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.055; 2009 IF: 4.162 |
Call Number |
UA @ lucian @ c:irua:77053 |
Serial |
597 |
Permanent link to this record |
|
|
|
Author |
Verbeeck, J.; Bertoni, G. |
Title |
Deconvolution of core electron energy loss spectra |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
109 |
Issue |
11 |
Pages |
1343-1352 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Different deconvolution methods for removing multiple scattering and instrumental broadening from core loss electron energy loss spectra are compared with special attention to the artefacts they introduce. The Gaussian modifier method, Wiener filter, maximum entropy, and model based methods are described. Their performance is compared on virtual spectra where the true single scattering distribution is known. A test on experimental spectra confirms the good performance of model based deconvolution in comparison to maximum entropy methods and shows the advantage of knowing the estimated error bars from a single spectrum acquisition. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000270765800005 |
Publication Date |
2009-07-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
13 |
Open Access |
|
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
Call Number |
UA @ lucian @ c:irua:79073UA @ admin @ c:irua:79073 |
Serial |
610 |
Permanent link to this record |
|
|
|
Author |
Titantah, J.T.; Lamoen, D.; Schowalter, M.; Rosenauer, A. |
Title |
Density-functional theory calculations of the electron energy-loss near-edge structure of Li-intercalated graphite |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
Volume |
47 |
Issue |
10 |
Pages |
2501-2510 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We have studied the structural and electronic properties of lithium-intercalated graphite (LIG) for various Li content. Atomic relaxation shows that Li above the center of the carbon hexagon in a AAAA stacked graphite is the only stable Li configuration in stage 1 intercalated graphite. Lithium and Carbon 1s energy-loss near-edge structure (ELNES) calculations are performed on the Li-intercalated graphite using the core-excited density-functional theory formulation. Several features of the Li 1s ELNES are correlated with reported experimental features. The ELNES spectra of Li is found to be electron beam orientation sensitive and this property is used to assign the origin of the various Li 1s ELNES features. Information about core-hole screening by the valence electrons and charge transfer in the LIG systems is obtained from the C 1s ELNES and valence charge density difference calculations, respectively. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000268429000025 |
Publication Date |
2009-05-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0008-6223; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.337 |
Times cited |
12 |
Open Access |
|
Notes |
Fwo G.0425.05; Esteem 026019 |
Approved |
Most recent IF: 6.337; 2009 IF: 4.504 |
Call Number |
UA @ lucian @ c:irua:77973 |
Serial |
638 |
Permanent link to this record |
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|
|
Author |
Xu, W.; Peeters, F.M.; Lu, T.C. |
Title |
Dependence of resistivity on electron density and temperature in graphene |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
7 |
Pages |
073403,1-073403,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
On the basis of the momentum-balance equation derived from the Boltzmann equation in which electron interactions with impurities and acoustic and optic phonons are included, we examine the dependence of the resistivity in graphene on temperature and electron density. Simple analytical expressions for the different contributions to the resistivity are obtained. Our results reproduce recent experimental findings and we are able to understand the different temperature dependence of the resistivity for low and high density samples. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000263815800013 |
Publication Date |
2009-02-12 |
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 |
31 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:76222 |
Serial |
642 |
Permanent link to this record |
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|
|
Author |
De Bie, C.; Martens, T.; van Dijk, J.; van der Mullen, J.J.A.M.; Bogaerts, A. |
Title |
Description of the plasma chemistry in an atmospheric pressure CH4 dielectric barrier discharge using a two dimensional fluid model |
Type |
P1 Proceeding |
Year |
2009 |
Publication |
|
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
13-16 |
Keywords |
P1 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
S.l. |
Editor |
|
Language |
|
Wos |
|
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:85692 |
Serial |
654 |
Permanent link to this record |
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|
|
Author |
Turner, S.; Lebedev, O.I.; Shenderova, O.; Vlasov, I.I.; Verbeeck, J.; Van Tendeloo, G. |
Title |
Determination of size, morphology, and nitrogen impurity location in treated detonation nanodiamond by transmission electron microscopy |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
Volume |
19 |
Issue |
13 |
Pages |
2116-2124 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Size, morphology, and nitrogen impurity location, all of which are all thought to be related to the luminescent properties of detonation nanodiamonds, are determined in several detonation nanodiamond samples using a combination of transmission electron microscopy techniques. Results obtained from annealed and cleaned detonation nanodiamond samples are compared to results from conventionally purified detonation nanodiamond. Detailed electron energy loss spectroscopy combined with model-based quantification provides direct evidence for the sp3 like embedding of nitrogen impurities into the diamond cores of all the studied nanodiamond samples. Simultaneously, the structure and morphology of the cleaned detonation nanodiamond particles are studied using high resolution transmission electron microscopy. The results show that the size and morphology of detonation nanodiamonds can be modified by temperature treatment and that by applying a special cleaning procedure after temperature treatment, nanodiamond particles with clean facets almost free from sp2 carbon can be prepared. These clean facets are clear evidence that nanodiamond cores are not necessarily in coexistence with a graphitic shell of non-diamond carbon. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000268297800012 |
Publication Date |
2009-05-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1616-301X;1616-3028; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
100 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 12.124; 2009 IF: 6.990 |
Call Number |
UA @ lucian @ c:irua:78261UA @ admin @ c:irua:78261 |
Serial |
674 |
Permanent link to this record |
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|
|
Author |
Doenen, M.; Zhang, L.; Erni, R.; Williams, O.A.; Hardy, A.; van Bael, M.K.; Wagner, P.; Haenen, K.; Nesladek, M.; Van Tendeloo, G. |
Title |
Diamond nucleation by carbon transport from buried nanodiamond TiO2 sol-gel composites |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
Volume |
21 |
Issue |
6 |
Pages |
670-673 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Weinheim |
Editor |
|
Language |
|
Wos |
000263492000007 |
Publication Date |
2008-12-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0935-9648;1521-4095; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
19.791 |
Times cited |
20 |
Open Access |
|
Notes |
Fwo; Iap-P6/42; Esteem 026019 |
Approved |
Most recent IF: 19.791; 2009 IF: NA |
Call Number |
UA @ lucian @ c:irua:76329 |
Serial |
688 |
Permanent link to this record |
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|
|
Author |
Li, B.; Partoens, B.; Peeters, F.M.; Magnus, W. |
Title |
Dielectric mismatch effect on coupled impurity states in a freestanding nanowire |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microelectronics journal |
Abbreviated Journal |
Microelectron J |
Volume |
40 |
Issue |
3 |
Pages |
446-448 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We studied the coupled impurity states in a freestanding semiconductor nanowire (NW), within the effective mass approximation and including the effect of the dielectric mismatch, by using finite element method. Bonding and anti-bonding states are found and their energies converge with increasing distance di between the two impurities. The dependence of the binding energy on the wire radius R and the distance di between the two impurities is investigated, and we compare it with the result of a freestanding NW that contains a single impurity. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Luton |
Editor |
|
Language |
|
Wos |
000264694700017 |
Publication Date |
2008-07-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0026-2692; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.163 |
Times cited |
4 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.163; 2009 IF: 0.778 |
Call Number |
UA @ lucian @ c:irua:76410 |
Serial |
690 |
Permanent link to this record |
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|
|
Author |
Li, B.; Partoens, B.; Peeters, F.M.; Magnus, W. |
Title |
Dielectric mismatch effect on coupled shallow impurity states in a semiconductor nanowire |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
8 |
Pages |
085306,1-085306,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Coupled shallow impurity states in a freestanding semiconductor nanowire and in a semiconductor nanowire surrounded by a metallic gate are studied within the effective-mass approximation. Bonding and antibonding states are found due to the coupling of the two impurities, and their energy converges with increasing distance di between the two impurities. The dependences of the binding energy on the wire radius R, the distance di between the two impurities, and the impurity radial position in the nanowire are examined. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000263816000051 |
Publication Date |
2009-02-09 |
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 |
11 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:76223 |
Serial |
691 |
Permanent link to this record |
|
|
|
Author |
Barbier, M.; Vasilopoulos, P.; Peeters, F.M. |
Title |
Dirac electrons in a Kronig-Penney potential: dispersion relation and transmission periodic in the strength of the barriers |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
20 |
Pages |
205415,1-205415,5 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The transmission T and conductance G through one or multiple one-dimensional, ä-function barriers of two-dimensional fermions with a linear energy spectrum are studied. T and G are periodic functions of the strength P of the ä-function barrier V(x,y)/ℏvF=Pä(x). The dispersion relation of a Kronig-Penney (KP) model of a superlattice is also a periodic function of P and causes collimation of an incident electron beam for P=2ðn and n integer. For a KP superlattice with alternating sign of the height of the barriers the Dirac point becomes a Dirac line for P=(n+1/2)ð. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000272311400101 |
Publication Date |
2009-12-04 |
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 |
93 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:80316 |
Serial |
707 |
Permanent link to this record |
|
|
|
Author |
Lin, K.; Pescarmona, P.P.; Houthoofd, K.; Liang, D.; Van Tendeloo, G.; Jacobs, P.A. |
Title |
Direct room-temperature synthesis of methyl-functionalized Ti-MCM-41 nanoparticles and their catalytic performance in epoxidation |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of catalysis |
Abbreviated Journal |
J Catal |
Volume |
263 |
Issue |
1 |
Pages |
75-82 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Methyl-functionalized Ti-MCM-41 nanoparticles with a size of 80 to 160 nm (Me-Ti-MCM-41 NP) were directly prepared via a dilute solution route by the co-condensation of tetraethoxysilane and methylalkoxysilanes in sodium hydroxide medium at room temperature. The characterization results showed the existence of ordered hexagonal mesoporous structure and tetrahedral Ti species in the nanoparticles. In the epoxidation of cyclohexene with tert-butyl hydroperoxide and aqueous H2O2, Me-Ti-MCM-41 NP samples displayed higher turnover frequencies (TOFs) for cyclohexene and initial reaction rates compared to Ti-MCM-41 and methyl-functionalized Ti-MCM-41 with normal particle size and to non-functionalized Ti-MCM-41 nanoparticles. Simultaneously, a higher selectivity for cyclohexene epoxide was observed in the case of aqueous H2O2, suggesting that the hydrolysis of cyclohexene epoxide with water is reduced on Me-Ti-MCM-41 NP samples. The improved catalytic behavior of Me-Ti-MCM-41 NP is discussed both in terms of the nanosize and methylation of the surface of the catalyst particles. The regeneration of Me-Ti-MCM-41 NP with tert-butyl hydroperoxide solution was evaluated via washing and calcination approaches. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
San Diego, Calif. |
Editor |
|
Language |
|
Wos |
000265000800008 |
Publication Date |
2009-02-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-9517; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.844 |
Times cited |
89 |
Open Access |
|
Notes |
Iwt; Iap; Goa |
Approved |
Most recent IF: 6.844; 2009 IF: 5.288 |
Call Number |
UA @ lucian @ c:irua:76395 |
Serial |
720 |
Permanent link to this record |
|
|
|
Author |
Li, J.; Chang, K.; Peeters, F.M. |
Title |
Dyakonov-Perel spin relaxation in InSb/AlxIn1-xSb quantum wells |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
15 |
Pages |
153307,1-153307,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate theoretically the Dyakonov-Perel spin relaxation time by solving the eight-band Kane model and Poisson equation self-consistently. Our results show distinct behavior with the single-band model due to the anomalous spin-orbit interactions in narrow band-gap semiconductors, and agree well with the experiment values reported in recent experiment [K. L. Litvinenko et al., New J. Phys. 8, 49 (2006)]. We find a strong resonant enhancement of the spin relaxation time appears for spin align along [11̅ 0] at a certain electron density at 4 K. This resonant peak is smeared out with increasing the temperature. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000271352000015 |
Publication Date |
2009-11-02 |
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 |
6 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:79996 |
Serial |
760 |
Permanent link to this record |
|
|
|
Author |
Tkachenko, D.V.; Misko, V.R.; Peeters, F.M. |
Title |
Dynamics of colloids in a narrow channel driven by a nonuniform force |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
Volume |
80 |
Issue |
5 |
Pages |
051401,1-051401,10 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using Brownian dynamics simulations, we investigate the dynamics of colloids confined in two-dimensional narrow channels driven by a nonuniform force Fdr(y). We considered linear-gradient, parabolic, and deltalike driving-force profiles. This driving force induces melting of the colloidal solid (i.e., shear-induced melting), and the colloidal motion experiences a transition from elastic to plastic regime with increasing Fdr. For intermediate Fdr (i.e., in the transition region) the response of the system, i.e., the distribution of the velocities of the colloidal chains õi(y), in general does not coincide with the profile of the driving force Fdr(y), and depends on the magnitude of Fdr, the width of the channel, and the density of colloids. For example, we show that the onset of plasticity is first observed near the boundaries while the motion in the central region is elastic. This is explained by: (i) (in)commensurability between the chains due to the larger density of colloids near the boundaries, and (ii) the gradient in Fdr. Our study provides a deeper understanding of the dynamics of colloids in channels and could be accessed in experiments on colloids (or in dusty plasma) with, e.g., asymmetric channels or in the presence of a gradient potential field. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000272309500045 |
Publication Date |
2009-11-10 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.366 |
Times cited |
14 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.366; 2009 IF: 2.400 |
Call Number |
UA @ lucian @ c:irua:80313 |
Serial |
774 |
Permanent link to this record |
|
|
|
Author |
Bach, D.; Schneider, R.; Gerthsen, D.; Verbeeck, J.; Sigle, W. |
Title |
EELS of niobium and stoichiometric niobium-oxide phases: part 1: plasmon and Near-edges fine structure |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Microscopy and microanalysis |
Abbreviated Journal |
Microsc Microanal |
Volume |
15 |
Issue |
6 |
Pages |
505-523 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A comprehensive electron energy-loss spectroscopy study of niobium (Nb) and stable Nb-oxide phases (NbO, NbO2, Nb2O5) was carried out. In this work (Part I), the plasmons and energy-loss near-edge structures (ELNES) of all relevant Nb edges (Nb-N2,3, Nb-M4,5, Nb-M2,3, Nb-M1, and Nb-L2,3) up to energy losses of about 2600 eV and the O-K edge are analyzed with respect to achieving characteristic fingerprints of Nb in different formal oxidation states (0 for metallic Nb, +2 for NbO, +4 for NbO2, and +5 for Nb2O5). Chemical shifts of the Nb-N2,3, Nb-M4,5, Nb-M2,3, and Nb-L2,3 edges are extracted from the spectra that amount to about 4 eV as the oxidation state increases from 0 for Nb to +5 for Nb2O5. Four different microscopes, including a 200 keV ZEISS Libra with monochromator, were used. The corresponding wide range of experimental parameters with respect to the primary electron energy, convergence, and collection semi-angles as well as energy resolution allows an assessment of the influence of the experimental setup on the ELNES of the different edges. Finally, the intensity of the Nb-L2,3 white-line edges is correlated with niobium 4d-state occupancy in the different reference materials. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge, Mass. |
Editor |
|
Language |
|
Wos |
000272433200005 |
Publication Date |
2009-10-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1431-9276;1435-8115; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.891 |
Times cited |
55 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.891; 2009 IF: 3.035 |
Call Number |
UA @ lucian @ c:irua:80320UA @ admin @ c:irua:80320 |
Serial |
790 |
Permanent link to this record |
|
|
|
Author |
Van Aert, S.; Chang, L.Y.; Bals, S.; Kirkland, A.I.; Van Tendeloo, G. |
Title |
Effect of amorphous layers on the interpretation of restored exit waves |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
Volume |
109 |
Issue |
3 |
Pages |
237-246 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The effects of amorphous layers on the quality of exit wave restorations have been investigated. Two independently developed software implementations for exit wave restoration have been used to simulated focal series of images of SrTiO3 with amorphous carbon layers incorporated. The restored exit waves have been compared both qualitatively and quantitatively. We have shown that amorphous layers have a strong impact on the quantitative measurements of atomic column positions, however, the error in the position measurements is still in the picometer range. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000264280200005 |
Publication Date |
2008-11-15 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0304-3991; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.843 |
Times cited |
10 |
Open Access |
|
Notes |
Fwo; Esteem 026019 |
Approved |
Most recent IF: 2.843; 2009 IF: 2.067 |
Call Number |
UA @ lucian @ c:irua:76421 |
Serial |
796 |
Permanent link to this record |
|
|
|
Author |
Khalil-Allafi, J.; Amin-Ahmadi, B. |
Title |
The effect of chemical composition on enthalpy and entropy changes of martensitic transformations in binary NiTi shape memory alloys |
Type |
P3 Proceeding |
Year |
2009 |
Publication |
Journal Of Alloys And Compounds |
Abbreviated Journal |
J Alloy Compd |
Volume |
487 |
Issue |
|
Pages |
363-366 |
Keywords |
P3 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
In the present research work the binary NiTi alloys with various compositions in the range of 50.351 at.% Ni were used. Samples have been annealed at 850 °C for 15 min and then quenched in water. In order to characterize transformation temperatures and enthalpy changes of the forward and the reverse martensitic transformation, Differential Scanning Calorimetric (DSC) experiments were performed. The enthalpy and entropy changes as a function of Ni atomic content have been thermodynamically investigated. Results show that enthalpy and entropy changes of martensitic transformation decrease when Ni atomic content increases. The variation of enthalpy and entropy of martensitic transformation with Ni content in binary NiTi alloys were explained by thermodynamic parameters and electron concentration of alloy (e/a) respectively. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000272521900073 |
Publication Date |
2009-07-31 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
Proceedings of the 22nd International Conference on the Physics of Semiconductors |
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0925-8388; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.133 |
Times cited |
30 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.133; 2009 IF: 2.135 |
Call Number |
UA @ lucian @ c:irua:122040 |
Serial |
804 |
Permanent link to this record |
|
|
|
Author |
Berdiyorov, G.R.; Yu, S.H.; Xiao, Z.L.; Peeters, F.M.; Hua, J.; Imre, A.; Kwok, W.K. |
Title |
Effect of sample geometry on the phase boundary of a mesoscopic superconducting loop |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
6 |
Pages |
064511,1-064511,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We studied the effect of sample geometry on the evolution of the superconducting state in nanoscale Nb circular and square loops by transport measurements. A multistage resistive transition with temperature is found for both samples, which is related to the effect of contact leads made from the same superconducting material. The H-T phase diagrams close to Tc0 show clear periodic oscillations on top of a parabolic background, i.e., Little-Parks effect. However, the amplitude of the oscillations decreases faster in the circular loop compared to the one in the square sample. Numerical simulations are conducted within the nonlinear Ginzburg-Landau theory to show the effect of sample geometry on the nucleation of superconductivity in superconducting loop structures. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000269638800067 |
Publication Date |
2009-08-17 |
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 |
21 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:78292 |
Serial |
833 |
Permanent link to this record |
|
|
|
Author |
Neira, I.S.; Kolen'ko, Y.V.; Lebedev, O.I.; Van Tendeloo, G.; Gupta, H.S.; Guitián, F.; Yoshimura, M. |
Title |
An effective morphology control of hydroxyapatite crystals via hydrothermal synthesis |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Crystal growth & design |
Abbreviated Journal |
Cryst Growth Des |
Volume |
9 |
Issue |
1 |
Pages |
466-474 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A facile urea-assisted hydrothermal synthesis and systematic characterization of hydroxyapatite (HA) with calcium nitrate tetrahydrate and diammonium hydrogen phosphate as precursors are reported. The advantage of the proposed technique over previously reported synthetic approaches is the simple but precise control of the HA crystals morphology, which is achieved by employing an intensive, stepwise, and slow thermal decomposition of urea as well as varying initial concentrations of starting reagents. Whereas the plate-, hexagonal prism- and needle-like HA particles preferentially growth along the c-axis, the smaller and fine-plate-like HA crystals demonstrate crystal growth along the (102) and (211) directions, uncommon for HA. Furthermore, it was established that the hydrothermally derived powdered products are phase-pure HA containing CO32− anions in the crystal lattice, that is, AB-type carbonated hydroxyapatite. Transmission electron microscopy (TEM) and electron diffraction (ED) of selected samples reveal that the as-prepared HA crystals are single-crystalline and exhibit a nearly defect-free microstructure. The hardness and elastic modulus of the hexagonal prism-like HA crystals have been investigated on a nanoscale using the nanoindentation technique; the observed trends are discussed. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000262332700073 |
Publication Date |
2008-11-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1528-7483;1528-7505; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.055 |
Times cited |
183 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 4.055; 2009 IF: 4.162 |
Call Number |
UA @ lucian @ c:irua:75740 |
Serial |
853 |
Permanent link to this record |
|
|
|
Author |
Hamelet, S.; Gibot, P.; Casas-Cabanas, M.; Bonnin, D.; Grey, C.P.; Cabana, J.; Leriche, J.B.; Rodriguez-Carvajal, J.; Courty, M.; Levasseur, S.; Carlach, P.; Van Thournout, M.; Tarascon, J.M.; Masquelier, C.; |
Title |
The effects of moderate thermal treatments under air on LiFePO4-based nano powders |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
Volume |
19 |
Issue |
23 |
Pages |
3979-3991 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The thermal behavior under air of LiFePO(4)-based powders was investigated through the combination of several techniques such as temperature-controlled X-ray diffraction, thermogravimetric analysis and Mossbauer and NMR spectroscopies. The reactivity with air at moderate temperatures depends on the particle size and leads to progressive displacement of Fe from the core structure yielding nano-size Fe(2)O(3) and highly defective, oxidized Li(x)Fe(y)PO(4) compositions whose unit-cell volume decreases dramatically when the temperature is raised between 400 and 600 K. The novel LiFePO(4)-like compositions display new electrochemical reactivity when used as positive electrodes in Li batteries. Several redox phenomena between 3.4 V and 2.7 V vs. Li were discovered and followed by in-situ X-ray diffraction, which revealed two distinct solid solution domains associated with highly anisotropic variations of the unit-cell constants. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000266615800024 |
Publication Date |
2009-05-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
93 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:94582 |
Serial |
867 |
Permanent link to this record |
|
|
|
Author |
Dominiczak, M.; Ruyter, A.; Limelette, P.; Monot-Laffez, I.; Giovannelli, F.; Rossell, M.D.; Van Tendeloo, G. |
Title |
Effects of nanocracks on the magnetic and electrical properties of La0.8Sr0.2MnO3 single crystals |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Solid state communications |
Abbreviated Journal |
Solid State Commun |
Volume |
149 |
Issue |
37/38 |
Pages |
1543-1548 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
An investigation of the physical properties of La0.8Sr0.2MnO3 single crystals grown by the molten zone technique is realized close to the metal-to-insulator transition temperature (TMI). In this paper, we review the effect of the structural defects through magnetotransport and local magnetic microstructures. From electron microscopy observations, some nanocrack defects (i.e. defects at a nanometer scale) were found, essentially in the center part of the single crystals. At room temperature, magnetic force microscopy measurements have shown that the absence of defects allowed a magnetic ordering of the domains at the crystal edge, which is the best-crystallized region. In addition, the magnetization loops have permitted us to verify that the crystal was ferromagnetically weaker in the center. On analyzing the electrical resistivity data, we observed in the linear current regime a sensitive variation of the resistivity due to defects, by comparing the center and the edge of the material at TMI. Additionally, at strong current, non-linearity phenomena have been supposed to be related to local heating. Finally, we discuss the structural disorder effect on the relaxation of the ferromagnetic domains. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000269679500012 |
Publication Date |
2009-06-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0038-1098; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.554 |
Times cited |
3 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.554; 2009 IF: 1.837 |
Call Number |
UA @ lucian @ c:irua:78289 |
Serial |
868 |
Permanent link to this record |
|
|
|
Author |
Bogaerts, A. |
Title |
Effects of oxygen addition to argon glow discharges: a hybrid Monte Carlo-fluid modeling investigation |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Spectrochimica acta: part B : atomic spectroscopy |
Abbreviated Journal |
Spectrochim Acta B |
Volume |
64 |
Issue |
11/12 |
Pages |
1266-1279 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
A hybrid model is developed for describing the effects of oxygen addition to argon glow discharges. The species taken into account in the model include Ar atoms in the ground state and the metastable level, O2 gas molecules in the ground state and two metastable levels, O atoms in the ground state and one metastable level, O3 molecules, Ar+, O+, O2+ and O− ions, as well as the electrons. The hybrid model consists of a Monte Carlo model for electrons and fluid models for the other plasma species. In total, 87 different reactions between the various plasma species are taken into account. Calculation results include the species densities and the importance of their production and loss processes, as well as the dissociation degree of oxygen. The effect of different O2 additions on these calculation results, as well as on the sputtering rates, is discussed. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000272910300016 |
Publication Date |
2009-10-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0584-8547; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.241 |
Times cited |
39 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.241; 2009 IF: 2.719 |
Call Number |
UA @ lucian @ c:irua:79271 |
Serial |
869 |
Permanent link to this record |
|
|
|
Author |
Avetisyan, A.A.; Partoens, B.; Peeters, F.M. |
Title |
Electric-field control of the band gap and Fermi energy in graphene multilayers by top and back gates |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
19 |
Pages |
195401,1-195401,11 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
It is known that a perpendicular electric field applied to multilayers of graphene modifies the electronic structure near the K point and may induce an energy gap in the electronic spectrum which is tunable by the gate voltage. Here we consider a system of graphene multilayers in the presence of a positively charged top and a negatively charged back gate to control independently the density of electrons on the graphene layers and the Fermi energy of the system. The band structure of three- and four-layer graphene systems in the presence of the top and back gates is obtained using a tight-binding approach. A self-consistent Hartree approximation is used to calculate the induced charges on the different graphene layers. We predict that for opposite and equal charges on the top and bottom layers an energy gap is opened at the Fermi level. For an even number of layers this gap is larger than in the case of an odd number of graphene layers. We find that the circular asymmetry of the spectrum, which is a consequence of the trigonal warping, changes the size of the induced electronic gap, even when the total density of the induced electrons on the graphene layers is low. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000272311000087 |
Publication Date |
2009-11-10 |
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 |
106 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:80315 |
Serial |
883 |
Permanent link to this record |
|
|
|
Author |
Avetisyan, A.A.; Partoens, B.; Peeters, F.M. |
Title |
Electric field tuning of the band gap in graphene multilayers |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
3 |
Pages |
035421,1-035421,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A perpendicular electric field applied to multilayers of graphene modifies the electronic structure near the K point and may induce an energy gap in the electronic spectrum. This gap is tunable by the gate voltage and its size depends on the number of layers. We use a tight-binding approach to calculate the band structure and include a self-consistent calculation in order to obtain the density of charge carriers. Results are presented for systems consisting of three and four layers of graphene. The effect of the circular asymmetry of the band structure on the gap is critically examined. |
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 |
|
Language |
|
Wos |
000262978200119 |
Publication Date |
2009-01-30 |
Series Editor |
|
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 |
106 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:75984 |
Serial |
887 |
Permanent link to this record |
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Author |
Moshnyaga, V.; Gehrke, K.; Sudheendra, L.; Belenchuk, A.; Raabe, S.; Shapoval, O.; Verbeeck, J.; Van Tendeloo, G.; Samwer, K. |
Title |
Electrical nonlinearity in colossal magnetoresistance manganite films: relevance of correlated polarons |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
13 |
Pages |
134413,1-134413,8 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The metal-insulator (MI) transition in epitaxial thin films of La0.75Ca0.25MnO3 (LCMO) is accompanied by the appearance of an intrinsic electrical nonlinearity. The latter, probed by electrical third harmonic voltage, U3, or resistance, R3=dU3/dJ, is drastically enhanced in the vicinity of the MI transition, TMI=267 K. Applied magnetic field, B=5 T, suppresses the nonlinearity, resulting in a huge nonlinear CMR3(TMI)~105%. R3 shows a peculiar low-frequency (1 kHz) dependence, R3~(-0)n, with exponent, n, changing across the MI transition from n~1,52 for TTMI to n=1 (T<TMI). The observed electrical nonlinearity in LCMO reflects the behavior of correlated polarons, the number of which dramatically enhances in the vicinity of TMI. We argued that correlated polarons, considered as electric-elastic quadrupoles, provide a nonlinear (quadratic) coupling to the electric field, yielding a third harmonic electric nonlinearity in LCMO. The reference film of La0.7Sr0.3MnO3 (LSMO), a prototypic double exchange system with second-order phase transition, is characterized as a linear metallic material in the whole range of temperatures (T=10400 K), magnetic fields (B=05 T), and frequencies (=11000 Hz). |
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 |
|
Wos |
000265942800074 |
Publication Date |
2009-04-09 |
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 |
28 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:77022UA @ admin @ c:irua:77022 |
Serial |
893 |
Permanent link to this record |
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Author |
Felten, A.; Ghijsen, J.; Pireaux, J.-J.; Drube, W.; Johnson, R.L.; Liang, D.; Hecq, M.; Van Tendeloo, G.; Bittencourt, C. |
Title |
Electronic structure of Pd nanoparticles on carbon nanotubes |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Micron |
Abbreviated Journal |
Micron |
Volume |
40 |
Issue |
1 |
Pages |
74-79 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The effect of the oxygen plasma treatment on the electronic states of multi-wall carbon nanotubes (MWCNTs) is analyzed by X-ray photoemission measurements (XPS) and UPS, both using synchrotron radiation. It is found that the plasma treatment effectively grafts oxygen at the CNT-surface. Thereafter, the interaction between evaporated Pd and pristine or oxygen plasma-treated MWCNTs is investigated. Pd is found to nucleate at defective sites, whether initially present or introduced by oxygen plasma treatment. The plasma treatment induced a uniform dispersion of Pd clusters at the CNT-surface. The absence of additional features in the Pd 3d and C I s core levels spectra testifies that no Pd-C bond is formed. The shift of the Pd 3d core level towards high-binding energy for the smallest clusters is attributed to the Coulomb energy of the charged final state. (C) 2008 Elsevier Ltd. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000261420900015 |
Publication Date |
2008-02-21 |
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 |
0968-4328; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.98 |
Times cited |
44 |
Open Access |
|
Notes |
Pai 608 |
Approved |
Most recent IF: 1.98; 2009 IF: 1.626 |
Call Number |
UA @ lucian @ c:irua:94578 |
Serial |
1015 |
Permanent link to this record |
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Author |
Zarenia, M.; Pereira, J.M.; Peeters, F.M.; Farias, G.A. |
Title |
Electrostatically confined quantum rings in bilayer graphene |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
Volume |
9 |
Issue |
12 |
Pages |
4088-4092 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We propose a new system where electron and hole states are electrostatically confined into a quantum ring in bilayer graphene. These structures can be created by tuning the gap of the graphene bilayer using nanostructured gates or by position-dependent doping. The energy levels have a magnetic field (B0) dependence that is strikingly distinct from that of usual semiconductor quantum rings. In particular, the eigenvalues are not invariant under a B0 ¨ −B0 transformation and, for a fixed total angular momentum index m, their field dependence is not parabolic, but displays two minima separated by a saddle point. The spectra also display several anticrossings, which arise due to the overlap of gate-confined and magnetically confined states. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Washington |
Editor |
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Language |
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Wos |
000272395400023 |
Publication Date |
2009-08-25 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1530-6984;1530-6992; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.712 |
Times cited |
42 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 12.712; 2009 IF: 9.991 |
Call Number |
UA @ lucian @ c:irua:80318 |
Serial |
1024 |
Permanent link to this record |