Records |
Author |
Ludu, A. |
Title |
Fiber bundle description of flow and nonlinear hydrodynamics on circles |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Journal of nonlinear mathematical physics |
Abbreviated Journal |
J Nonlinear Math Phy |
Volume |
15 |
Issue |
|
Pages |
157-170 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We introduce a differential geometry description of the path lines, stream lines and particles contours in hydrodynamics. We present a generalized form of a Korteweg-de Vries type of equation for the exterior of a circle. Nonlinearities from the boundary conditions, surface tension and the Euler equations are taken into account, but the flow is considered inviscid and irrotational. For the circular case we describe the traveling waves shapes, solitons and the particles trajectories. |
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 |
000263517200012 |
Publication Date |
2008-09-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1402-9251;1776-0852; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.986 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 0.986; 2008 IF: 0.760 |
Call Number |
UA @ lucian @ c:irua:94603 |
Serial |
1189 |
Permanent link to this record |
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Author |
De Backer, A.; Van Aert, S.; Faes, C.; Arslan Irmak, E.; Nellist, P.D.; Jones, L. |
Title |
Experimental reconstructions of 3D atomic structures from electron microscopy images using a Bayesian genetic algorithm |
Type |
A1 Journal article |
Year |
2022 |
Publication |
N P J Computational Materials |
Abbreviated Journal |
npj Comput Mater |
Volume |
8 |
Issue |
1 |
Pages |
216 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We introduce a Bayesian genetic algorithm for reconstructing atomic models of monotype crystalline nanoparticles from a single projection using Z-contrast imaging. The number of atoms in a projected atomic column obtained from annular dark field scanning transmission electron microscopy images serves as an input for the initial three-dimensional model. The algorithm minimizes the energy of the structure while utilizing a priori information about the finite precision of the atom-counting results and neighbor-mass relations. The results show promising prospects for obtaining reliable reconstructions of beam-sensitive nanoparticles during dynamical processes from images acquired with sufficiently low incident electron doses. |
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 |
000866500900001 |
Publication Date |
2022-10-12 |
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 |
2057-3960 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
Notes |
This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S.V.A. and Grant 823717 ESTEEM3). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0267.18N, G.0502.18N, G.0346.21N) and a postdoctoral grant to A.D.B. L.J. acknowledges Science Foundation Ireland (SFI – grant number URF/RI/191637), the Royal Society, and the AMBER Centre. The authors acknowledge Aakash Varambhia for his assistance and expertise with the experimental recording and use of characterization facilities within the David Cockayne Centre for Electron Microscopy, Department of Materials, University of Oxford, and in particular the EPSRC (EP/K040375/1 South of England Analytical Electron Microscope).; esteem3reported; esteem3JRA |
Approved |
Most recent IF: NA |
Call Number |
EMAT @ emat @c:irua:191398 |
Serial |
7114 |
Permanent link to this record |
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|
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Author |
Turner, S.; Lebedev, O.I.; Schroeder, F.; Fischer, R.A.; Van Tendeloo, G. |
Title |
Direct imaging of loaded metal-organic framework materials (metal@MOF-5) |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
20 |
Issue |
17 |
Pages |
5622-5627 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We illustrate the potential of advanced transmission electron microscopy for the characterization of a new class of soft porous materials: metal@Zn4O(bdc)3 (metal@MOF-5; bdc = 1,4-benzenedicarboxylate). By combining several electron microscopy techniques (transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), electron diffraction (ED), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and electron tomography) and by carefully reducing the electron dose to avoid beam damage, it is possible to simultaneously characterize the MOF-5 framework material and the loaded metal nanoparticles. We also demonstrate that electron tomography can be used to accurately determine the position and distribution of the particles within the MOF-5 framework. To demonstrate the implementation of these microscopy techniques and what kind of results can be expected, measurements on gas-phase-loaded metal−organic framework materials Ru@MOF-5 and Pd@MOF-5 are presented. |
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 |
000258941400021 |
Publication Date |
2008-08-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
112 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 9.466; 2008 IF: 5.046 |
Call Number |
UA @ lucian @ c:irua:76595 |
Serial |
714 |
Permanent link to this record |
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|
Author |
Connolly, M.R.; Bemding, S.J.; Milošević, M.V.; Clem, J.R.; Tamegai, T. |
Title |
Continuum versus discrete flux behaviour in large mesoscopic Bi2Sr2CaCu2O8+\delta disks |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
Volume |
470 |
Issue |
S:1 |
Pages |
S896-S897 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We have used scanning Hall probe and local Hall magnetometry measurements to map flux profiles in superconducting Bi2Sr2CaCu2O8+δ disks whose diameters span the crossover between the bulk and mesoscopic vortex regimes. The behaviour of large disks (greater-or-equal, slanted20 μm diameter) is well described by analytic models that assume a continuous distribution of flux in the sample. Small disks (less-than-or-equals, slant10 μm diameter), on the other hand, exhibit clear signatures of the underlying discrete vortex structure as well as competition between triangular Abrikosov ordering and the formation of shell structures driven by interactions with circulating edge currents. At low fields we are able to directly observe the characteristic mesoscopic compression of vortex clusters which is linked to oscillations in the diameter of the vortex dome in increasing magnetic fields. At higher fields, where single vortex resolution is lost, we are still able to track configurational changes in the vortex patterns, since competing vortex orders impose unmistakable signatures on local magnetisation curves. Our observations are in excellent agreement with molecular-dynamics numerical simulations which lead us to a natural definition of the lengthscale for the crossover between discrete and continuum behaviour in our system. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000286075700384 |
Publication Date |
2009-11-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
1.404 |
Times cited |
|
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 1.404; 2010 IF: 1.415 |
Call Number |
UA @ lucian @ c:irua:88069 |
Serial |
494 |
Permanent link to this record |
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Author |
Bending, S.J.; Neal, J.S.; Milošević, M.V.; Potenza, A.; san Emeterio, L.; Marrows, C.H. |
Title |
Vortex-antivortex 'molecular crystals' in hybrid ferromagnet/superconductor structures |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
|
Volume |
150 |
Issue |
5 |
Pages |
052019 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We have used high resolution Hall probe microscopy to image vortex-antivortex (V-AV) 'molecules' induced in superconducting Pb films by the stray fields from square arrays of ferromagnetic Co/Pt dots. We have directly observed spontaneous V-AV pairs and studied how they interact with added 'free' (anti)fluxons in an applied magnetic field. We observe a rich variety of subtle phenomena arising from competing symmetries in our system which can either drive added antivortices to join AV shells around nanomagnets or stabilise the translationally symmetric AV lattice between the dots. Added vortices annihilate AV shells, leading eventually to a stable 'nulling' state with no free fluxons, which should exhibit a strongly (field-)enhanced critical current. At higher densities we actually observe vortex shells around the magnets, stabilised by the asymmetric anti-pinning potential. Our experimental findings are in good agreement with Ginzburg-Landau 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 |
Bristol |
Editor |
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Language |
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Wos |
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Publication Date |
2009-04-01 |
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 |
1742-6588;1742-6596; |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:106136 |
Serial |
3855 |
Permanent link to this record |
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Author |
Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B. |
Title |
Hydrogen impurities and native defects in CdO |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
110 |
Issue |
6 |
Pages |
063521,1-063521,7 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
We have used first-principles calculations based on density functional theory to study point defects in CdO within the local density approximation and beyond (LDA+U). Hydrogen interstitials and oxygen vacancies are found to act as shallow donors and can be interpreted as the cause of conductivity in CdO. Hydrogen can also occupy an oxygen vacancy in its substitutional form and also acts as a shallow donor. Similar to what was found for ZnO and MgO, hydrogen creates a multicenter bond with its six oxygen neighbors in CdO. The charge neutrality level for native defects and hydrogen impurities has been calculated. It is shown that in the case of native defects, it is not uniquely defined. Indeed, this level depends highly on the chemical potentials of the species and one can obtain different values for different end states in the experiment. Therefore, a comparison with experiment can only be made if the chemical potentials of the species in the experiment are well defined. However, for the hydrogen interstitial defect, since this level is independent of the chemical potential of hydrogen, one can obtain a unique value for the charge neutrality level. We find that the Fermi level stabilizes at 0.43 eV above the conduction band minimum in the case of the hydrogen interstitial defect, which is in good agreement with the experimentally reported value of 0.4 eV. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000295619300041 |
Publication Date |
2011-09-23 |
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 |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
13 |
Open Access |
|
Notes |
; The authors gratefully acknowledge financial support from the IWT-Vlaanderen through the ISIMADE project, the FWO-Vlaanderen through Project G.0191.08 and the BOF-NOI of the University of Antwerp. This work was carried out using the HPC infrastructure at the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC. ; |
Approved |
Most recent IF: 2.068; 2011 IF: 2.168 |
Call Number |
UA @ lucian @ c:irua:93613 |
Serial |
1533 |
Permanent link to this record |
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Author |
Connolly, M.R.; Milošević, M.V.; Bending, S.J.; Tamegai, T. |
Title |
Magneto-optical imaging of flux penetration into arrays of Bi2Sr2CaCu2O8 microdisks |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
78 |
Issue |
13 |
Pages |
132501,1-132501,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We have used differential magneto-optical (MO) imaging to investigate the mixed state of superconducting Bi2Sr2CaCu2O8+ (BSCCO) microdisks fabricated on a single-crystal sample. MO difference images of the stray field distribution over a range of out-of-plane fields allow us to distinguish between flux that is penetrating the disks and that entering the underlying BSCCO platelet. We find that flux preferentially flows along linear defects into the interstitial platelet regions up to a characteristic field Hp, above which flux enters the disks. We identify this as the field of first penetration of pancake vortices over the Bean-Livingston barrier around the disks, where Hp(T) at intermediate temperatures is well described by an exponentially decaying function with a characteristic temperature T0=19 K. At a given temperature, a minority of the disks exhibit a lower penetration field and we correlate the location of these disks with the linear defects in the BSCCO crystal. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
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Wos |
000260574200018 |
Publication Date |
2008-10-01 |
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 |
8 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
Call Number |
UA @ lucian @ c:irua:75658 |
Serial |
1901 |
Permanent link to this record |
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Author |
Lok, J.G.S.; Geim, A.K.; Maan, J.C.; Marmorkos, I.; Peeters, F.M.; Mori, N.; Eaves, L.; McDonnell, P.; Henini, M.; Sakai, J.W.; Main, P.C.; |
Title |
Resonant tunnelling through D- states |
Type |
A1 Journal article |
Year |
1996 |
Publication |
Surface science : a journal devoted to the physics and chemistry of interfaces
T2 – 11th International Conference on the Electronic Properties of 2-Dimensional Systems (EP2DS XI), August 07-11, 1995, Univ. Nottingham, Nottingham, England |
Abbreviated Journal |
Surf Sci |
Volume |
362 |
Issue |
1-3 |
Pages |
247-250 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We have studied tunnelling through Si donors incorporated in the quantum well of double barrier resonant tunnelling devices. In addition to a resonance associated with the ground state of a single donor (1s level), a novel donor-related resonance at a smaller binding energy is observed in high magnetic fields where it becomes dominant over the Is resonance. We attribute this novel feature to a D-minus state of a shallow donor. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Elsevier |
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
A1996UZ03300061 |
Publication Date |
2002-07-26 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0039-6028; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
1.925 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
INSTRUMENTS & INSTRUMENTATION 31/56 Q3 # NUCLEAR SCIENCE & TECHNOLOGY 9/32 Q2 # PHYSICS, PARTICLES & FIELDS 24/28 Q4 # SPECTROSCOPY 28/43 Q3 # |
Call Number |
UA @ lucian @ c:irua:95892 |
Serial |
2895 |
Permanent link to this record |
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Author |
Lebedev, N.; Stehno, M.; Rana, A.; Gauquelin, N.; Verbeeck, J.; Brinkman, A.; Aarts, J. |
Title |
Inhomogeneous superconductivity and quasilinear magnetoresistance at amorphous LaTiO₃/SrTiO₃ interfaces |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Journal Of Physics-Condensed Matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
33 |
Issue |
5 |
Pages |
055001 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We have studied the transport properties of LaTiO3/SrTiO3 (LTO/STO) heterostructures. In spite of 2D growth observed in reflection high energy electron diffraction, transmission electron microscopy images revealed that the samples tend to amorphize. Still, we observe that the structures are conducting, and some of them exhibit high conductance and/or superconductivity. We established that conductivity arises mainly on the STO side of the interface, and shows all the signs of the two-dimensional electron gas usually observed at interfaces between STO and LTO or LaAlO3, including the presence of two electron bands and tunability with a gate voltage. Analysis of magnetoresistance (MR) and superconductivity indicates the presence of spatial fluctuations of the electronic properties in our samples. That can explain the observed quasilinear out-of-plane MR, as well as various features of the in-plane MR and the observed superconductivity. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
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Language |
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Wos |
000588209300001 |
Publication Date |
2020-10-14 |
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 |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.7 |
Times cited |
1 |
Open Access |
OpenAccess |
Notes |
; NL and JA gratefully acknowledge the financial support of the research program DESCO, which is financed by the Netherlands Organisation for Scientific Research (NWO). The authors thank J Jobst, S Smink, K Lahabi and G Koster for useful discussion. ; |
Approved |
Most recent IF: 2.7; 2020 IF: 2.649 |
Call Number |
UA @ admin @ c:irua:173679 |
Serial |
6545 |
Permanent link to this record |
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Author |
Vávra, O.; Gaži, S.; Golubović, D.S.; Vávra, I.; Dérer, J.; Verbeeck, J.; Van Tendeloo, G.; Moshchalkov, V.V. |
Title |
0 and π phase Josephson coupling through an insulating barrier with magnetic impurities |
Type |
A1 Journal article |
Year |
2006 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
74 |
Issue |
2 |
Pages |
020502 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We have studied the temperature and field dependencies of the critical current I(C) in the Nb-Fe(0.1)Si(0.9)-Nb Josephson junction with a tunneling barrier formed by a paramagnetic insulator. We demonstrate that in these junctions coexistence of both the 0 and the pi states within one tunnel junction occurs, and leads to the appearance of a sharp cusp in the temperature dependence I(C)(T), similar to the I(C)(T) cusp found for the 0-pi transition in metallic pi junctions. This cusp is not related to the 0-pi temperature-induced transition itself, but is caused by the different temperature dependencies of the opposing 0 and pi supercurrents through the barrier. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000239426600010 |
Publication Date |
2006-07-15 |
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 |
27 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2006 IF: 3.107 |
Call Number |
UA @ lucian @ c:irua:60087 c:irua:60087 c:irua:60087 c:irua:60087UA @ admin @ c:irua:60087 |
Serial |
1 |
Permanent link to this record |
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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 |
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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 |
000268429000025 |
Publication Date |
2009-05-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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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 |
Nikolaev, A.V.; Michel, K.H. |
Title |
Molecular terms and optical transitions of C60n+/- molecular ions |
Type |
P1 Proceeding |
Year |
2002 |
Publication |
AIP conference proceedings
T2 – 16th International Winterschool on Electronic Properties of Novel, Materials, MAR 02-09, 2002, KIRCHBERG, AUSTRIA |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
417-420 |
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
We have studied the molecular energy terms of the hole configurations (h(u)(+))(m), m=2,3,4,5 of C-60(m+) cations and the electronic configurations (t(1u))(n) n=2,3,4, as well as (t(1u))(n-1)t(1g) of the C-60(n-) anions. The lowest terms (within an energy span of 0.03 eV) for C-60(2+) are three triplets T-3(1g), (3)G(g), T-3(2g) and for C-60(3+) are three quartets T-4(1u), (4)G(u), T-4(2u), which favor Jahn-Teller distortions. For the ground state of C-60(2-) we find a triplet T-3(1g) in agreement with Hund's rules. Our method takes into account intramolecular direct and exchange multipolar Coulomb interactions. |
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 |
Editor |
|
Language |
|
Wos |
|
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
633 |
Series Issue |
|
Edition |
|
ISSN |
0-7354-0088-1 |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:103905 |
Serial |
2187 |
Permanent link to this record |
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Author |
Li, Z.Z.; Raffy, H.; Bals, S.; Van Tendeloo, G.; Megtert, S. |
Title |
Interplay of doping and structural modulation in superconducting Bi2Sr2-xLaxCuO6+\delta thin films |
Type |
A1 Journal article |
Year |
2005 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
71 |
Issue |
17 |
Pages |
174503,1-7 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We have studied the evolution of the structural modulation in epitaxial, c-axis-oriented, Bi2Sr2-xLaCuO6+delta thin films when varying the La content x and for a given x as a function of oxygen content. A series of thin films with 0 <= x <= 0.8 has been prepared in situ by rf-magnetron sputtering and characterized by R(T) measurements, Rutherford backscattering spectroscopy, transmission electron microscopy, and x-ray diffraction techniques. The oxygen content of each individual film was varied by thermal annealing across the phase diagram. The evolution of the structural modulation has been thoroughly studied by x-ray diffraction in determining the variation of the amplitude of satellite reflections in special two axes 2 theta/theta-theta scans (reciprocal space scans). It is shown that the amplitude of the modulation along the c axis decreases strongly when x increases from 0 to 0.2. It is demonstrated that this variation is essentially governed by La content x and that changing the oxygen content by thermal treatments has a much lower influence, even becoming negligible for x > 0.2. Such study is important to understand the electronical properties of Bi2Sr2-xLaxCuO6+gamma thin films. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000229935000092 |
Publication Date |
2005-05-06 |
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; 2005 IF: 3.185 |
Call Number |
UA @ lucian @ c:irua:54746 |
Serial |
1707 |
Permanent link to this record |
|
|
|
Author |
Nikolaev, A.V.; Verberck, B.; Ionova, G.V. |
Title |
Molecular interaction energies and optimal configuration of a cubane dimer |
Type |
A1 Journal article |
Year |
2010 |
Publication |
International journal of quantum chemistry |
Abbreviated Journal |
Int J Quantum Chem |
Volume |
110 |
Issue |
5 |
Pages |
1063-1069 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We have studied the dependence of the binding energy of a cubane dimer on the mutual orientation of and the distance between the composing monomers employing the second-order Møller-Plesset perturbation scheme (MP2) with the cc-pVDZ molecular basis set. We have found that the MP2 contribution from the molecular correlations is responsible for the bound state of the cubane dimer, whereas the Hartree-Fock contribution remains anti-bonding at all intermolecular distances. Starting with two molecules in the standard orientation and centers of mass at (0,0,0) and (0,0,d), respectively, the maximal binding energy is found at d = 5.125 Å and one of the monomers rotated by 45° about the z-axis. This configuration implies that the hydrogen atoms belonging to different monomers tend to repel each other. The results are in agreement with experimental data on the optimal packing of cubane molecules in the solid state. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000274720000011 |
Publication Date |
2009-04-10 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0020-7608;1097-461X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.92 |
Times cited |
1 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 2.92; 2010 IF: 1.302 |
Call Number |
UA @ lucian @ c:irua:81944 |
Serial |
2179 |
Permanent link to this record |
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|
|
Author |
Willems, B.L.; Taylor, D.M.J.; Fritzsche, J.; Malfait, M.; Vanacken, J.; Moshchalkov, V.V.; Montoya, E.; Van Tendeloo, G. |
Title |
Temperature and magnetic field dependence of the voltagein GaAs films with superconducting Ga grains |
Type |
A1 Journal article |
Year |
2008 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
Volume |
66 |
Issue |
1 |
Pages |
25-28 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We have studied granular films consisting of nanoscale Ga droplets formed on GaAs films via a method of vacuum annealing to promote As evaporation. For temperatures and magnetic fields below the bulk Ga critical parameters, the samples are very sensitive towards external microwave radiation when two point voltage measurements are performed. Together with the observation of an oscillating magnetic field dependence of the voltage, a scenario in which the samples consist of Josephson-coupled loops seems to be the most likely one for explaining the obtained results. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Berlin |
Editor |
|
Language |
|
Wos |
000262831300004 |
Publication Date |
2008-10-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1434-6028;1434-6036; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
1.461 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.461; 2008 IF: 1.568 |
Call Number |
UA @ lucian @ c:irua:75997 |
Serial |
3496 |
Permanent link to this record |
|
|
|
Author |
Misko, V.R.; Fomin, V.M.; Devreese, J.T.; Moshchalkov, V.V. |
Title |
Stability of vortex-antivortex “molecules” in mesoscopic superconducting triangles |
Type |
A1 Journal article |
Year |
2005 |
Publication |
|
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
191-196 |
Keywords |
A1 Journal article; Electron Microscopy for Materials Science (EMAT); |
Abstract |
We have revealed thermodynamically stable vortex-antivortex configurations in mesoscopic type I superconducting equilateral triangles. The revealed effect is explained by two factors: (i) vortex confinement in mesoscopic triangles and (ii) appearance of the vortex-antivortex repulsion in mesoscopic type I superconductor triangles in the vicinity of the dual point. The stability of the obtained solutions is examined as a function of material and external parameters – the Ginzburg-Landau parameter K and temperature – as well as a function of a distortion of the sample's shape. The vortex-antivortex. “molecule” turns out to be stable in a wide range of the parameters that makes it possible its experimental visualization. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000234363700030 |
Publication Date |
2007-11-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
3rd International Symposium on Mesoscopic Superconductivity and, Spintronics, MAR 01-04, 2004, Atsug |
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:103704 |
Serial |
3134 |
Permanent link to this record |
|
|
|
Author |
Mikhailova, D.; Reichel, P.; Tsirlin, A.A.; Abakumov, A.M.; Senyshyn, A.; Mogare, K.M.; Schmidt, M.; Kuo, C.Y.; Pao, C.W.; Pi, T.W.; Lee, J.F.; Hu, Z.; Tjeng, L.H.; |
Title |
Oxygen-driven competition between low-dimensional structures of Sr3CoMO6 and Sr3CoMO7-\delta with M = Ru,Ir |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
Dalton T |
Volume |
43 |
Issue |
37 |
Pages |
13883-13891 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We have realized a reversible structure transformation of one-dimensional 1D K4CdCl6-type Sr3CoMO6 with the Co2+/M4+ cation ordering into the two-dimensional 2D double layered Ruddlesden-Popper structure Sr3CoMO7-delta with a random distribution of Co and M (with M = Ru, Ir) upon increasing the partial oxygen pressure. The combined soft and hard X-ray absorption spectroscopy studies show that under transformation, Co and M cations were oxidized to Co3+ and M5+. During oxidation, high-spin Co2+ in Sr3CoMO6 first transforms into high-spin Co3+ in oxygen-deficient Sr3CoMO7-delta, and then further transforms into low-spin Co3+ in fully oxidized Sr3CoMO7 upon further increasing the partial pressure of oxygen. The 1D Sr3CoMO6 compound is magnetically ordered at low temperatures with the magnetic moments lying along the c-axis. Their alignment is parallel for Sr3CoRuO6 and antiparallel for Sr3CoIrO6. The 2D compounds reveal a spin-glass-like behavior related to the random distribution of magnetic cations in the structure. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000342074100009 |
Publication Date |
2014-07-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1477-9226;1477-9234; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.029 |
Times cited |
7 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.029; 2014 IF: 4.197 |
Call Number |
UA @ lucian @ c:irua:119960 |
Serial |
2545 |
Permanent link to this record |
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|
|
Author |
Navío, C.; Vallejos, S.; Stoycheva, T.; Llobet, E.; Correig, X.; Snyders, R.; Blackman, C.; Umek, P.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.; |
Title |
Gold clusters on WO3 nanoneedles grown via AACVD : XPS and TEM studies |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Materials chemistry and physics |
Abbreviated Journal |
Mater Chem Phys |
Volume |
134 |
Issue |
2/3 |
Pages |
809-813 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We have prepared tungsten oxide films decorated with gold particles on Si substrates by aerosol assisted chemical vapor deposition (AACVD) and characterized them using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). SEM shows that the films are composed of needle-like structures and TEM shows that both the needles and the gold particles are crystalline. XPS indicates the presence of oxygen vacancies, i.e. the films are WO3−x, and hence the deposited material is composed of semiconducting nanostructures and that the interaction between the gold particles and the WO3 needles surface is weak. The synthesis of semiconducting tungsten oxide nanostructures decorated with metal particles represents an important step towards the development of sensing devices with optimal properties. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
000305918200038 |
Publication Date |
2012-04-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0254-0584; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.084 |
Times cited |
52 |
Open Access |
|
Notes |
Iap |
Approved |
Most recent IF: 2.084; 2012 IF: 2.072 |
Call Number |
UA @ lucian @ c:irua:97705 |
Serial |
1356 |
Permanent link to this record |
|
|
|
Author |
Bekaert, J.; Saniz, R.; Partoens, B.; Lamoen, D. |
Title |
Native point defects in CuIn1-xGaxSe2 : hybrid density functional calculations predict the origin of p- and n-type conductivity |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
Volume |
16 |
Issue |
40 |
Pages |
22299-22308 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
We have performed a first-principles study of the p- and n-type conductivity in CuIn1−xGaxSe2 due to native point defects, based on the HSE06 hybrid functional. Band alignment shows that the band gap becomes larger with x due to the increasing conduction band minimum, rendering it hard to establish n-type conductivity in CuGaSe2. From the defect formation energies, we find that In/GaCu is a shallow donor, while VCu, VIn/Ga and CuIn/Ga act as shallow acceptors. Using the total charge neutrality of ionized defects and intrinsic charge carriers to determine the Fermi level, we show that under In-rich growth conditions InCu causes strongly n-type conductivity in CuInSe2. Under increasingly In-poor growth conditions, the conductivity type in CuInSe2 alters to p-type and compensation of the acceptors by InCu reduces, as also observed in photoluminescence experiments. In CuGaSe2, the native acceptors pin the Fermi level far away from the conduction band minimum, thus inhibiting n-type conductivity. On the other hand, CuGaSe2 shows strong p-type conductivity under a wide range of Ga-poor growth conditions. Maximal p-type conductivity in CuIn1−xGaxSe2 is reached under In/Ga-poor growth conditions, in agreement with charge concentration measurements on samples with In/Ga-poor stoichiometry, and is primarily due to the dominant acceptor CuIn/Ga. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000343072800042 |
Publication Date |
2014-09-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1463-9076;1463-9084; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.123 |
Times cited |
43 |
Open Access |
|
Notes |
; We gratefully acknowledge financial support from the science fund FWO-Flanders through project G.0150.13. The first-principles calculations have been carried out on the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Centre (VSC), supported financially by the Hercules foundation and the Flemish Government (EWI Department). We also like to thank Prof. S. Siebentritt of the University of Luxembourg for a presentation of her work on GIGS during a visit to our research group and for helpful discussions of our results. ; |
Approved |
Most recent IF: 4.123; 2014 IF: 4.493 |
Call Number |
UA @ lucian @ c:irua:120465 |
Serial |
2284 |
Permanent link to this record |
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|
|
Author |
Leenaerts, O.; Partoens, B.; Peeters, F.M. |
Title |
Graphene: a perfect nanoballoon |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
93 |
Issue |
19 |
Pages |
193107,1-193107,3 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We have performed a first-principles density functional theory investigation of the penetration of helium atoms through a graphene monolayer with defects. The relaxation of the graphene layer caused by the incoming helium atoms does not have a strong influence on the height of the energy barriers for penetration. For defective graphene layers, the penetration barriers decrease exponentially with the size of the defects but they are still sufficiently high that very large defects are needed to make the graphene sheet permeable for small atoms and molecules. This makes graphene a very promising material for the construction of nanocages and nanomembranes. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000260944100090 |
Publication Date |
2008-11-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
295 |
Open Access |
|
Notes |
This work was supported by the Flemish Science Foundation (FWO-Vl), the NOI-BOF of the University of Antwerp, and the Belgian Science Policy (IAP). |
Approved |
Most recent IF: 3.411; 2008 IF: 3.726 |
Call Number |
UA @ lucian @ c:irua:73196 |
Serial |
1368 |
Permanent link to this record |
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|
Author |
Wang, H.; Picot, T.; Houben, K.; Moorkens, T.; Grigg, J.; Van Haesendonck, C.; Biermans, E.; Bals, S.; Brown, S.A.; Vantomme, A.; Temst, K.; Van Bael, M.J.; |
Title |
The superconducting proximity effect in epitaxial Al/Pb nanocomposites |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
Volume |
27 |
Issue |
1 |
Pages |
015008-8 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We have investigated the superconducting properties of Pb nanoparticles with a diameter ranging from 8 to 20 nm, synthesized by Pb+ ion implantation in a crystalline Al matrix. A detailed structural characterization of the nanocomposites reveals the highly epitaxial relation between the Al crystalline matrix and the Pb nanoparticles. The Al/Pb nanocomposites display a single superconducting transition, with the critical temperature T-c increasing with the Pb content. The dependence of T-c on the Pb/Al volume ratio was compared with theoretical models of the superconducting proximity effect based on the bulk properties of Al and Pb. A very good correspondence with the strong-coupling proximity effect model was found, with an electron-phonon coupling constant in the Pb nanoparticles slightly reduced compared to bulk Pb. Our result differs from other studies on Pb nanoparticle based proximity systems where weak-coupling models were found to better describe the T-c dependence. We infer that the high interface quality resulting from the ion implantation synthesis method is a determining factor for the superconducting properties. Critical field and critical current measurements support the high quality of the nanocomposite superconducting films. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000328275000010 |
Publication Date |
2013-11-28 |
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 |
Not_Open_Access |
Notes |
; This work was supported by the Research Foundation-Flanders (FWO), the KU Leuven BOF Concerted Research Action programs (GOA/09/006, the KU Leuven BOF CREA/12/015 project, and GOA/14/007) and the EU FP7 program SPIRIT (227012). TP and KH are postdoctoral research fellow and doctoral fellow of the FWO. ; |
Approved |
Most recent IF: 2.878; 2014 IF: 2.325 |
Call Number |
UA @ lucian @ c:irua:112833 |
Serial |
3599 |
Permanent link to this record |
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|
Author |
Borgatti, F.; Park, C.; Herpers, A.; Offi, F.; Egoavil, R.; Yamashita, Y.; Yang, A.; Kobata, M.; Kobayashi, K.; Verbeeck, J.; Panaccione, G.; Dittmann, R.; |
Title |
Chemical insight into electroforming of resistive switching manganite heterostructures |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
Volume |
5 |
Issue |
9 |
Pages |
3954-3960 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
We have investigated the role of the electroforming process in the establishment of resistive switching behaviour for Pt/Ti/Pr0.5Ca0.5MnO3/SrRuO3 layered heterostructures (Pt/Ti/PCMO/SRO) acting as non-volatile Resistance Random Access Memories (RRAMs). Electron spectroscopy measurements demonstrate that the higher resistance state resulting from electroforming of as-prepared devices is strictly correlated with the oxidation of the top electrode Ti layer through field-induced electromigration of oxygen ions. Conversely, PCMO exhibits oxygen depletion and downward change of the chemical potential for both resistive states. Impedance spectroscopy analysis, supported by the detailed knowledge of these effects, provides an accurate model description of the device resistive behaviour. The main contributions to the change of resistance from the as-prepared (low resistance) to the electroformed (high resistance) states are respectively due to reduced PCMO at the boundary with the Ti electrode and to the formation of an anisotropic np junction between the Ti and the PCMO layers. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000317859400051 |
Publication Date |
2013-03-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2040-3364;2040-3372; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.367 |
Times cited |
40 |
Open Access |
|
Notes |
Vortex; Countatoms ECASJO_; |
Approved |
Most recent IF: 7.367; 2013 IF: 6.739 |
Call Number |
UA @ lucian @ c:irua:108710UA @ admin @ c:irua:108710 |
Serial |
348 |
Permanent link to this record |
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|
|
Author |
Nyssen, J.; Fetene, F.; Dessie, M.; Alemayehu, G.; Sewnet, A.; Wassie, A.; Kibret, M.; Walraevens, K.; Derudder, B.; Nicolai, B.; Annys, S.; Tegegne, F.; Van Passel, S.; Frankl, A.; Verleyen, E.; Teklemariam, D.; Adgo, E. |
Title |
Persistence and changes in the peripheral Beles basin of Ethiopia |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Regional Environmental Change |
Abbreviated Journal |
Reg Environ Change |
Volume |
18 |
Issue |
7 |
Pages |
2089-2104 |
Keywords |
A1 Journal article; Economics; Engineering Management (ENM) |
Abstract |
We have investigated the relevance of the notion of “peripheralism” in the Beles basin. In this lowland border area of Ethiopia, important investments require an evaluation of their socio-economic and ecological impacts in the light of Ethiopia's Climate-Resilient Green Economy (CRGE) strategy. We contrasted literature of different periods with field observations. In the middle and lower parts of the basin, the Gumuz people traditionally practised shifting cultivation. Resettlement of highlanders is particularly linked to water and land resources. A large irrigation project was initiated in the 1980s, but vegetables and fruits face post-harvest losses. Large water transfers from Lake Tana since 2010 affect the movement of people, the hydrogeomorphology, and ecology of the river. In several parts of the basin, the settlers' economy now dominates. Many Gumuz became sedentary but maintained their agricultural system, particularly in the south of the lower basin. Land titling allowed allocation of “vacant” areas to transnational or domestic investors. As a result, the semi-natural vegetation is frequently replaced by open cropland, leading to decreased carbon storage and increased soil erosion. This and water abstraction for irrigation jeopardise hydropower production, in contradiction with the CRGE objectives. Despite the recent developments, the contrasts in economic activity make the core-periphery dichotomy to remain actual in the Beles basin. The resettlements and permanent cropping tend to make the upper basin part of the core. However, the installation of a transit road and commercial farms in the lower basin do not allow to consider that a non-peripheral integration has taken place. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000445234600017 |
Publication Date |
2018-04-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1436-3798 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.919 |
Times cited |
3 |
Open Access |
|
Notes |
; The authors acknowledge the numerous local inhabitants and authorities who shared their knowledge with us, particularly in Pawe and Dangur districts. All participants in group discussions and group excursions to the Beles basin are thanked for sharing ideas. The Institutional University Cooperation with Bahir Dar University (BDU-IUC), funded by the Belgian authorities, through the Flemish Interuniversity Council-University Development Cooperation, hosted the research activities. Lutgart Lenaerts (Norwegian University of Life Sciences) shared inspiring thoughts and Daniel Mege (Polish Academy of Sciences) provided useful documentation. Daniel Mege as well as Eric Movet (www.mydriase.fr) gave permission to use illustrations. The constructive comments on an earlier version of this paper by two anonymous reviewers and the editor are greatly acknowledged. ; |
Approved |
Most recent IF: 2.919 |
Call Number |
UA @ admin @ c:irua:154137 |
Serial |
6235 |
Permanent link to this record |
|
|
|
Author |
Martens, T.; Mihailova, D.; van Dijk, J.; Bogaerts, A. |
Title |
Theoretical characterization of an atmospheric pressure glow discharge used for analytical spectrometry |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
81 |
Issue |
21 |
Pages |
9096-9108 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We have investigated the plasma processes in an atmospheric pressure glow discharge (APGD) in He used for analytical spectrometry by means of fluid and Monte Carlo (MC) simulations. Typical results include the potential and electric field distributions in the plasma, the density profiles of the various plasma species throughout the discharge, the mean electron energy, as well as the rates of the various collision processes in the plasma, and the relative importance of the different production and loss rates for the various species. The similarities and differences with low-pressure glow discharges are discussed. The main differences are a very small cathode dark space region and a large positive column as well as the dominant role of molecular ions. Some characteristic features of the APGD, such as the occurrence of the different spatial zones in the discharge, are illustrated, with links to experimental observations. |
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 |
000276191900062 |
Publication Date |
2009-10-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700;1520-6882; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
15 |
Open Access |
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Notes |
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Approved |
Most recent IF: 6.32; 2009 IF: 5.214 |
Call Number |
UA @ lucian @ c:irua:79554 |
Serial |
3604 |
Permanent link to this record |
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Author |
Brück, S.; Paul, M.; Tian, H.; Müller, A.; Kufer, D.; Praetorius, C.; Fauth, K.; Audehm, P.; Goering, E.; Verbeeck, J.; Van Tendeloo, G.; Sing, M.; Claessen, R.; |
Title |
Magnetic and electronic properties of the interface between half metallic Fe3O4 and semiconducting ZnO |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
100 |
Issue |
8 |
Pages |
081603-081603,4 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We have investigated the magnetic depth profile of an epitaxial Fe3O4 thin film grown directly on a semiconducting ZnO substrate by soft x-ray resonant magnetic reflectometry (XRMR) and electron energy loss spectroscopy (EELS). Consistent chemical profiles at the interface between ZnO and Fe3O4 are found from both methods. Valence selective EELS and XRMR reveal independently that the first monolayer of Fe at the interface between ZnO and Fe3O4 contains only Fe3+ ions. Besides this narrow 2.5 Å interface layer, Fe3O4 shows magnetic bulk properties throughout the whole film making highly efficient spin injection in this system feasible. |
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 |
000300711200014 |
Publication Date |
2012-02-22 |
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 |
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ISSN |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
12 |
Open Access |
|
Notes |
The authors thank E. Pellegrin for helpful comments and S. Macke for help with the software REMAGX. S.B. acknowledges financial support by the HZB, Berlin, and the Australian Government via Grant No. RM08550. H.T. acknowledges funding from GOA project “XANES meets ELNES,” J.V. and G.V.T. acknowledge funding from the European Research Council under Grant No. 46791-COUN-TATOMS. The authors acknowledge financial support by the DFG through Forschergruppe FOR 1162. |
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
Call Number |
UA @ lucian @ c:irua:95041UA @ admin @ c:irua:95041 |
Serial |
1860 |
Permanent link to this record |
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Author |
Aydin, H.; Bacaksiz, C.; Yagmurcukardes, N.; Karakaya, C.; Mermer, O.; Can, M.; Senger, R.T.; Sahin, H.; Selamet, Y. |
Title |
Experimental and computational investigation of graphene/SAMs/n-Si Schottky diodes |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Applied Surface Science |
Abbreviated Journal |
Appl Surf Sci |
Volume |
428 |
Issue |
428 |
Pages |
1010-1017 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We have investigated the effect of two different self-assembled monolayers (SAMs) on electrical characteristics of bilayer graphene (BLG)/n-Si Schottky diodes. Novel 4“bis(diphenylamino)-1, 1':3”-terpheny1-5' carboxylic acids (TPA) and 4,4-di-9H-carbazol-9-y1-1,1':3'1'-terpheny1-5' carboxylic acid (CAR) aromatic SAMs have been used to modify n-Si surfaces. Cyclic voltammetry (CV) and Kelvin probe force microscopy (KPFM) results have been evaluated to verify the modification of n-Si surface. The current-voltage (I-V) characteristics of bare and SAMs modified devices show rectification behaviour verifying a Schottky junction at the interface. The ideality factors (n) from ln(I)-V dependences were determined as 2.13,1.96 and 2.07 for BLG/n-Si, BLG/TPA/n-Si and BLG/CAR/n-Si Schottky diodes, respectively. In addition, Schottky barrier height (SBH) and series resistance (Rs) of SAMs modified diodes were decreased compared to bare diode due to the formation of a compatible interface between graphene and Si as well as n-n interaction between aromatic SAMs and graphene. The CAR-based device exhibits better diode characteristic compared to the TPA-based device. Computational simulations show that the BLG/CAR system exhibits smaller energy-level-differences than the BLG/TPA, which supports the experimental findings of a lower Schottky barrier and series resistance in BLG/CAR diode. (C) 2017 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 |
000415227000128 |
Publication Date |
2017-09-29 |
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 |
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ISSN |
0169-4332 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.387 |
Times cited |
2 |
Open Access |
|
Notes |
; This work was supported by TUBITAK (The Scientific and Technical Research Council of Turkey) with project number 112T946. We also thank AQuReC (Applied Quantum Research Center) for Raman measurements. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges support from Bilim Akademisi The Science Academy, Turkey under the BAGEP program. ; |
Approved |
Most recent IF: 3.387 |
Call Number |
UA @ lucian @ c:irua:154608UA @ admin @ c:irua:154608 |
Serial |
5101 |
Permanent link to this record |
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Author |
Habermeier, H.U.; Razavi, F.; Lebedev, O.; Gross, G.M.; Praus, R.; Zhang, P.X. |
Title |
Correlation of microstructure and magnetotransport properties of epitaxially grown La-Ca-Mn-O3 thin films |
Type |
A1 Journal article |
Year |
1999 |
Publication |
Physica status solidi: B: basic research
T2 – International Conference on Solid State Spectroscopy – (ICSSS), SEP 05-07, 1999, SCHWABISCH-GMUND, GERMANY |
Abbreviated Journal |
Phys Status Solidi B |
Volume |
215 |
Issue |
1 |
Pages |
679-683 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We have investigated epitaxially grown single-crystalline Ca-doped LaMnO3 thin films using the pulsed laser deposition technique in a case study aimed to explore the possibilities buried in epitaxial stress tailoring in order to control the transport properties of CMR materials beyond the limits set by equilibrium thermodynamics. Depending on the film thickness there is an abrupt transition from pseudomorphic to epitaxial granular growth observable which is related to the epitaxial strain of the films. This is associated with microscopic stress relaxation and leads to well controllable modifications of the atomic arrangements of the Mn-O sublattice in the films. Due to the interrelation of double exchange, spin-, charge- and orbital ordering and the Jahn-Teller effect mediated coupling of the electronic system to the crystal lattice, the magnetotransport properties of the firms can be modified in a controllable way. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000082487800110 |
Publication Date |
2002-09-10 |
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 |
0370-1972;1521-3951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.674 |
Times cited |
3 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.674; 1999 IF: 0.978 |
Call Number |
UA @ lucian @ c:irua:103489 |
Serial |
527 |
Permanent link to this record |
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Author |
Brammertz, G.; Oueslati, S.; Buffiere, M.; Bekaert, J.; El Anzeery, H.; Messaoud, K.B.; Sahayaraj, S.; Nuytten, T.; Koble, C.; Meuris, M.; Poortmans, J.; |
Title |
Investigation of properties limiting efficiency in Cu2ZnSnSe4-based solar cells |
Type |
A1 Journal article |
Year |
2015 |
Publication |
IEEE journal of photovoltaics |
Abbreviated Journal |
Ieee J Photovolt |
Volume |
5 |
Issue |
5 |
Pages |
649-655 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
We have investigated different nonidealities in Cu2ZnSnSe4CdSZnO solar cells with 9.7% conversion efficiency, in order to determine what is limiting the efficiency of these devices. Several nonidealities could be observed. A barrier of about 300 meV is present for electron flow at the absorberbuffer heterojunction leading to a strong crossover behavior between dark and illuminated currentvoltage curves. In addition, a barrier of about 130 meV is present at the Moabsorber contact, which could be reduced to 15 meV by inclusion of a TiN interlayer. Admittance spectroscopy results on the devices with the TiN backside contact show a defect level with an activation energy of 170 meV. Using all parameters extracted by the different characterization methods for simulations of the two-diode model including injection and recombination currents, we come to the conclusion that our devices are limited by the large recombination current in the depletion region. Potential fluctuations are present in the devices as well, but they do not seem to have a special degrading effect on the devices, besides a probable reduction in minority carrier lifetime through enhanced recombination through the band tail defects. |
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 |
000353524800026 |
Publication Date |
2014-12-19 |
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 |
2156-3381;2156-3403; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.712 |
Times cited |
13 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.712; 2015 IF: 3.165 |
Call Number |
c:irua:123717 |
Serial |
1734 |
Permanent link to this record |
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Author |
Homm, P.; Dillemans, L.; Menghini, M.; Van Bilzen, B.; Bakalov, P.; Su, C.Y.; Lieten, R.; Houssa, M.; Nasr Esfahani, D.; Covaci, L.; Peeters, F.M.; Seo, J.W.; Locquet, J.P.; |
Title |
Collapse of the low temperature insulating state in Cr-doped V2O3 thin films |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
107 |
Issue |
107 |
Pages |
111904 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We have grown epitaxial Cr-doped V2O3 thin films with Cr concentrations between 0% and 20% on (0001)-Al2O3 by oxygen-assisted molecular beam epitaxy. For the highly doped samples (>3%), a regular and monotonous increase of the resistance with decreasing temperature is measured. Strikingly, in the low doping samples (between 1% and 3%), a collapse of the insulating state is observed with a reduction of the low temperature resistivity by up to 5 orders of magnitude. A vacuum annealing at high temperature of the films recovers the low temperature insulating state for doping levels below 3% and increases the room temperature resistivity towards the values of Cr-doped V2O3 single crystals. It is well-know that oxygen excess stabilizes a metallic state in V2O3 single crystals. Hence, we propose that Cr doping promotes oxygen excess in our films during deposition, leading to the collapse of the low temperature insulating state at low Cr concentrations. These results suggest that slightly Cr-doped V2O3 films can be interesting candidates for field effect devices. (C) 2015 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 |
000361639200020 |
Publication Date |
2015-09-19 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-6951; 1077-3118 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
14 |
Open Access |
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Notes |
; The authors acknowledge financial support from the FWO Project No. G052010N10 as well as the EU-FP7 SITOGA Project. P.H. acknowledges support from Becas Chile-CONICYT. ; |
Approved |
Most recent IF: 3.411; 2015 IF: 3.302 |
Call Number |
UA @ lucian @ c:irua:128728 |
Serial |
4149 |
Permanent link to this record |
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Author |
Brammertz, G.; Buffiere, M.; Verbist, C.; Bekaert, J.; Batuk, M.; Hadermann, J.; et al. |
Title |
Process variability in Cu2ZnSnSe4 solar cell devices: Electrical and structural investigations |
Type |
P1 Proceeding |
Year |
2015 |
Publication |
The conference record of the IEEE Photovoltaic Specialists Conference
T2 – IEEE 42nd Photovoltaic Specialist Conference (PVSC), JUN 14-19, 2015, New Orleans, LA |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
We have fabricated 9.7% efficient Cu2ZnSnSe4/CdS/ZnO solar cells by H2Se selenization of sequentially sputtered metal layers. Despite the good efficiency obtained, process control appears to be difficult. In the present contribution we compare the electrical and physical properties of two devices with nominal same fabrication procedure, but 1% and 9.7% power conversion efficiency respectively. We identify the problem of the lower performing device to be the segregation of ZnSe phases at the backside of the sample. This ZnSe seems to be the reason for the strong bias dependent photocurrent observed in the lower performing devices, as it adds a potential barrier for carrier collection. The reason for the different behavior of the two nominally same devices is not fully understood, but speculated to be related to sputtering variability. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Ieee |
Place of Publication |
New york |
Editor |
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Language |
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Wos |
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Publication Date |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
978-1-4799-7944-8 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:132335 |
Serial |
4229 |
Permanent link to this record |