Records |
Author |
Bertrand, L.; Robinet, L.; Thoury, M.; Janssens, K.; Cohen, S.X.; Schöder, S. |
Title |
Cultural heritage and archaeology materials studied by synchrotron spectroscopy and imaging |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Applied physics A : materials science & processing |
Abbreviated Journal |
Appl Phys A-Mater |
Volume |
106 |
Issue |
2 |
Pages |
377-396 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The use of synchrotron radiation techniques to study cultural heritage and archaeological materials has undergone a steep increase over the past 10-15 years. The range of materials studied is very broad and encompasses painting materials, stone, glass, ceramics, metals, cellulosic and wooden materials, and a cluster of organic-based materials, in phase with the diversity observed at archaeological sites, museums, historical buildings, etc. Main areas of investigation are: (1) the study of the alteration and corrosion processes, for which the unique non-destructive speciation capabilities of X-ray absorption have proved very beneficial, (2) the understanding of the technologies and identification of the raw materials used to produce archaeological artefacts and art objects and, to a lesser extent, (3) the investigation of current or novel stabilisation, conservation and restoration practices. In terms of the synchrotron methods used, the main focus so far has been on X-ray techniques, primarily X-ray fluorescence, absorption and diffraction, and Fourier-transform infrared spectroscopy. We review here the use of these techniques from recent works published in the field demonstrating the breadth of applications and future potential offered by third generation synchrotron techniques. New developments in imaging and advanced spectroscopy, included in the UV/visible and IR ranges, could even broaden the variety of materials studied, in particular by fostering more studies on organic and complex organic-inorganic mixtures, while new support activities at synchrotron facilities might facilitate transfer of knowledge between synchrotron specialists and users from archaeology and cultural heritage sciences. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000299749000009 |
Publication Date |
2011-11-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0947-8396 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.455 |
Times cited |
55 |
Open Access |
|
Notes |
; The authors acknowledge the critical reading by B. Berrie (National Gallery of Art, Washington DC, USA). We thank J. Mass (Conservation Department, Winterthur Museum and Country Estate, Winterthur, DE, USA), H. Roemich (Institute of Fine Arts, New York University, USA), J. Hiller (Non-Crystalline Diffraction Beamline, Diamond Light Source, Didcot, UK) and J.-P. Echard (Laboratoire de recherche et de restauration, Musee de la musique, Paris, France) for their comments on the presentation of their work in the manuscript. The IPANEMA platform is jointly developed by CNRS, MNHN, the French Ministry of Culture and Communication and SOLEIL, and benefits from a CPER grant (MESR, Region Ile-de-France). Support by the Access to Research Infrastructures activity in the 7th Framework Programme of the EU (CHARISMA Grant Agreement n. 228330) and the NWO Science4Arts programme are acknowledged. ; |
Approved |
Most recent IF: 1.455; 2012 IF: 1.545 |
Call Number |
UA @ admin @ c:irua:99166 |
Serial |
5561 |
Permanent link to this record |
|
|
|
Author |
Croitoru, M.D.; Vagov, A.; Shanenko, A.A.; Axt, V.M. |
Title |
The Cooper problem in nanoscale : enhancement of the coupling due to confinement |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
Volume |
25 |
Issue |
12 |
Pages |
124001-124005 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In 1956 Cooper demonstrated (1956 Phys. Rev. 104 1189) that, no matter how weak the attraction is, two electrons in three-dimensional (3D) space just above the Fermi sea could be bound. In this work we investigate the influence of confinement on the binding energy of a Cooper pair. We show that confinement-induced modification of the Fermi sea results in a significant increase of the binding energy, when the bottom of an energy subband is very close to the Fermi surface. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000311418100004 |
Publication Date |
2012-11-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0953-2048;1361-6668; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.878 |
Times cited |
9 |
Open Access |
|
Notes |
; MDC acknowledges support by the European Community under the Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR). ; |
Approved |
Most recent IF: 2.878; 2012 IF: 2.758 |
Call Number |
UA @ lucian @ c:irua:105121 |
Serial |
3573 |
Permanent link to this record |
|
|
|
Author |
Sena, S.H.R.; Pereira, J.M.; Farias, G.A.; Peeters, F.M.; Costa Filho, R.N. |
Title |
The electronic properties of graphene and graphene ribbons under simple shear strain |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
24 |
Issue |
37 |
Pages |
375301 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A tight-binding model is used to study the energy band of graphene and graphene ribbon under simple shear strain. The ribbon consists of lines of carbon atoms in an armchair or zigzag orientation where a simple shear strain is applied in the x-direction keeping the atomic distances in the y-direction unchanged. Such modification in the lattice gives an energy band that differs in several aspects from the one without any shear and with pure shear. The changes in the spectrum depend on the line displacement of the ribbon, and also on the modified hopping parameter. It is also shown that this simple shear strain tunes the electronic properties of both graphene and graphene ribbon, opening and closing energy gaps for different displacements of the system. The modified density of states is also shown. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000308202700011 |
Publication Date |
2012-08-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
15 |
Open Access |
|
Notes |
; This work was supported by CNPq (RNCF), the National Council for the Improvement of Higher Education (CAPES), the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the bilateral program between Flanders and Brazil. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
Call Number |
UA @ lucian @ c:irua:101838 |
Serial |
1000 |
Permanent link to this record |
|
|
|
Author |
Dixit, H.; Saniz, R.; Cottenier, S.; Lamoen, D.; Partoens, B. |
Title |
Electronic structure of transparent oxides with the Tran-Blaha modified Becke-Johnson potential |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
24 |
Issue |
20 |
Pages |
205503-205503,9 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
We present electronic band structures of transparent oxides calculated using the Tran-Blaha modified Becke-Johnson (TB-mBJ) potential. We studied the basic n-type conducting binary oxides In2O3, ZnO, CdO and SnO2 along with the p-type conducting ternary oxides delafossite CuXO2 (X = Al, Ga, In) and spinel ZnX2O4 (X = Co, Rh, Ir). The results are presented for calculated band gaps and effective electron masses. We discuss the improvements in the band gap determination using TB-mBJ compared to the standard generalized gradient approximation (GGA) in density functional theory (DFT) and also compare the electronic band structure with available results from the quasiparticle GW method. It is shown that the calculated band gaps compare well with the experimental and GW results, although the electron effective mass is generally overestimated. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000303507100009 |
Publication Date |
2012-04-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
113 |
Open Access |
|
Notes |
Iwt; Fwo |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
Call Number |
UA @ lucian @ c:irua:98222 |
Serial |
1017 |
Permanent link to this record |
|
|
|
Author |
Kishore, V.V.R.; Čukarić, N.; Partoens, B.; Tadić, M.; Peeters, F.M. |
Title |
Hole subbands in freestanding nanowires : six-band versus eight-band k.p modelling |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
24 |
Issue |
13 |
Pages |
135302-135302,10 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The electronic structure of GaAs, InAs and InSb nanowires is studied using the six-band and the eight-band k.p models. The effect of the different Luttinger-like parameters (in the eight-band model) on the hole band structure is investigated. Although GaAs nanostructures are often treated within a six-band model because of the large bandgap, it is shown that an eight-band model is necessary for a correct description of its hole spectrum. The camel-back structure usually found in the six-band model is not always present in the eight-band model. This camel-back structure depends on the interaction between light and heavy holes, especially the ones with opposite spin. The latter effect is less pronounced in an eight-band model, but could be very sensitive to the Kane inter-band energy (E-P) value. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000302120100007 |
Publication Date |
2012-03-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
13 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), Belgian Science Policy (IAP) and the Ministry of Education and Science of Serbia. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
Call Number |
UA @ lucian @ c:irua:97763 |
Serial |
1479 |
Permanent link to this record |
|
|
|
Author |
Singh, K.; Maignan, A.; Simon, C.; Kumar, S.; Martin, C.; Lebedev, O.; Turner, S.; Van Tendeloo, G. |
Title |
Magnetodielectric CuCr0.5V0.5O2 : an example of a magnetic and dielectric multiglass |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
24 |
Issue |
22 |
Pages |
226002-226002,4 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The complex dielectric susceptibility and spin glass properties of polycrystalline CuCr0.5V 0.5O2 delafossite have been investigated. Electron diffraction, high resolution electron microscopy and electron energy loss spectroscopy show that the Cr3+ and V 3+ magnetic cations are randomly distributed on the triangular network of CdI2-type layers. In contrast to CuCrO2, CuCr0.5V 0.5O2 exhibits two distinctive (magnetic and electric) glassy states evidenced by memory effects in electric and magnetic susceptibilities. A large magnetodielectric coupling is observed at low temperature. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000304873300027 |
Publication Date |
2012-05-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
19 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
Call Number |
UA @ lucian @ c:irua:98380 |
Serial |
1916 |
Permanent link to this record |
|
|
|
Author |
Chen, Y.; Shanenko, A.A.; Croitoru, M.D.; Peeters, F.M. |
Title |
Quantum cascades in nano-engineered superconductors : geometrical, thermal and paramagnetic effects |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
24 |
Issue |
26 |
Pages |
265702 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The effect of a parallel magnetic field on the orbital motion of electrons in high-quality superconducting nanowires resulting in a superconductor-to-normal transition which occurs through a cascade of jumps in the order parameter as a function of the magnetic field. Such cascades originate from the transverse size quantization that splits the conduction band into a series of subbands. Here, based on a numerical solution of the Bogoliubov-de Gennes equations for a hollow nanocylinder, we investigate how the quantum-size cascades depend on the confining geometry, i.e., by changing the cylinder radius R and its thickness d we cover the range from the nanowire-like to the nanofilm-like regime. The cascades are shown to become much less pronounced when increasing R/d, i.e., when the nanofilm-like regime is approached. When the temperature is non-zero they are thermally smoothed. This includes the spin-magnetic-field interaction which reduces the critical (depairing) parallel magnetic field H-c,H-parallel to but does not have any qualitative effect on the quantum cascades. From our calculations it is seen that the paramagnetic limiting field H-par significantly exceeds H-c,H-parallel to even in extremely narrow nanocylinders, i.e., when R, d are down to a few nanometers, and H-c,H-parallel to is only about 10% larger when switching-off the spin-magnetic-field interaction in this case. Both characteristic fields, H-c,H-parallel to and H-par, exhibit pronounced quantum-size oscillations. We demonstrate that the quantum cascades and the quantum-size oscillations survive in the presence of surface roughness. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000305640800014 |
Publication Date |
2012-06-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
6 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI) and the ESF-AQDJJ network. MDC acknowledges the support of the EU Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR). ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
Call Number |
UA @ lucian @ c:irua:100281 |
Serial |
2773 |
Permanent link to this record |
|
|
|
Author |
Chen, Y.; Shanenko, A.A.; Perali, A.; Peeters, F.M. |
Title |
Superconducting nanofilms : molecule-like pairing induced by quantum confinement |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
24 |
Issue |
18 |
Pages |
185701-185701,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Quantum confinement of the perpendicular motion of electrons in single-crystalline metallic superconducting nanofilms splits the conduction band into a series of single-electron subbands. A distinctive feature of such a nanoscale multi-band superconductor is that the energetic position of each subband can vary significantly with changing nanofilm thickness, substrate material, protective cover and other details of the fabrication process. It can occur that the bottom of one of the available subbands is situated in the vicinity of the Fermi level. We demonstrate that the character of the superconducting pairing in such a subband changes dramatically and exhibits a clear molecule-like trend, which is very similar to the well-known crossover from the Bardeen-Cooper-Schrieffer regime to Bose-Einstein condensation (BCS-BEC) observed in trapped ultracold fermions. For Pb nanofilms with thicknesses of 4 and 5 monolayers (MLs) this will lead to a spectacular scenario: up to half of all the Cooper pairs nearly collapse, shrinking in the lateral size (parallel to the nanofilm) down to a few nanometers. As a result, the superconducting condensate will be a coherent mixture of almost molecule-like fermionic pairs with ordinary, extended Cooper pairs. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000303500900018 |
Publication Date |
2012-04-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
26 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). AAS thanks A Bianconi, M D Croitoru and A V Vagov for useful discussions. AAS acknowledges the hospitality and fruitful interactions with G C Strinati, P Pieri and D Neilson during his visit to the University of Camerino, supported by the School of Advanced Studies of the University of Camerino. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
Call Number |
UA @ lucian @ c:irua:98223 |
Serial |
3357 |
Permanent link to this record |
|
|
|
Author |
Lajevardipour, A.; Neek-Amal, M.; Peeters, F.M. |
Title |
Thermomechanical properties of graphene : valence force field model approach |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
24 |
Issue |
17 |
Pages |
175303-175303,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using the valence force field model of Perebeinos and Tersoff (2009 Phys. Rev. B 79 241409(R)), different energy modes of suspended graphene subjected to tensile or compressive strain are studied. By carrying out Monte Carlo simulations it is found that: (i) only for small strains (vertical bar epsilon vertical bar (sic) 0.02) is the total energy symmetrical in the strain, while it behaves completely differently beyond this threshold; (ii) the important energy contributions in stretching experiments are stretching, angle bending, an out-of-plane term, and a term that provides repulsion against pi-pi misalignment; (iii) in compressing experiments the two latter terms increase rapidly, and beyond the buckling transition stretching and bending energies are found to be constant; (iv) from stretching-compressing simulations we calculated the Young's modulus at room temperature 350 +/- 3.15 N m(-1), which is in good agreement with experimental results (340 +/- 50 N m(-1)) and with ab initio results (322-353) N m(-1); (v) molar heat capacity is estimated to be 24.64 J mol(-1) K-1 which is comparable with the Dulong-Petit value, i. e. 24.94 J mol(-1) K-1, and is almost independent of the strain; (vi) nonlinear scaling properties are obtained from height-height correlations at finite temperature; (vii) the used valence force field model results in a temperature independent bending modulus for graphene, and (viii) the Gruneisen parameter is estimated to be 0.64. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000303499700012 |
Publication Date |
2012-04-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
29 |
Open Access |
|
Notes |
; We acknowledge helpful comments by V Perebeinos, S Costamagna, A Fasolino and J H Los. This work was supported by the Flemish science foundation (FWO-Vl) and the Belgium Science Policy (IAP). ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
Call Number |
UA @ lucian @ c:irua:99123 |
Serial |
3639 |
Permanent link to this record |
|
|
|
Author |
Croitoru, M.D.; Shanenko, A.A.; Kaun, C.C.; Peeters, F.M. |
Title |
Ultra-small metallic grains : effect of statistical fluctuations of the chemical potential on superconducting correlations and vice versa |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
24 |
Issue |
27 |
Pages |
275701 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Superconducting correlations in an isolated metallic grain are governed by the interplay between two energy scales: the mean level spacing delta and the bulk pairing gap Delta(0), which are strongly influenced by the position of the chemical potential with respect to the closest single-electron level. In turn superconducting correlations affect the position of the chemical potential. Within the parity projected BCS model we investigate the probability distribution of the chemical potential in a superconducting grain with randomly distributed single-electron levels. Taking into account statistical fluctuations of the chemical potential due to the pairing interaction, we find that such fluctuations have a significant impact on the critical level spacing delta(c) at which the superconducting correlations cease: the critical ratio delta(c)/Delta(0) at which superconductivity disappears is found to be increased. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000305653100012 |
Publication Date |
2012-06-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
9 |
Open Access |
|
Notes |
; This work was supported by the European Community under the Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR), the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF network INSTANS. MDC and AAS are grateful to A Vagov for stimulating discussions. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
Call Number |
UA @ lucian @ c:irua:100280 |
Serial |
3793 |
Permanent link to this record |
|
|
|
Author |
Ray, S.; Kolen'ko, Y.V.; Kovnir, K.A.; Lebedev, O.I.; Turner, S.; Chakraborty, T.; Erni, R.; Watanabe, T.; Van Tendeloo, G.; Yoshimura, M.; Itoh, M. |
Title |
Defect controlled room temperature ferromagnetism in Co-doped barium titanate nanocrystals |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
Volume |
23 |
Issue |
2 |
Pages |
025702,1-025702,10 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Defect mediated high temperature ferromagnetism in oxide nanocrystallites is the central feature of this work. Here, we report the development of room temperature ferromagnetism in nanosized Co-doped barium titanate particles with a size of around 14 nm, synthesized by a solvothermal drying method. A combination of x-ray diffraction with state-of-the-art electron microscopy techniques confirms the intrinsic doping of Co into BaTiO3. The development of the room temperature ferromagnetism was tracked down to the different donor defects, namely hydroxyl groups at the oxygen site (\mathrm {OH}\mathrm {(O)} |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000298409000011 |
Publication Date |
2011-12-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.44 |
Times cited |
19 |
Open Access |
|
Notes |
Esteem 026019; Fwo |
Approved |
Most recent IF: 3.44; 2012 IF: 3.842 |
Call Number |
UA @ lucian @ c:irua:93636 |
Serial |
614 |
Permanent link to this record |
|
|
|
Author |
Schulze, A.; Hantschel, T.; Dathe, A.; Eyben, P.; Ke, X.; Vandervorst, W. |
Title |
Electrical tomography using atomic force microscopy and its application towards carbon nanotube-based interconnects |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
Volume |
23 |
Issue |
30 |
Pages |
305707 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The fabrication and integration of low-resistance carbon nanotubes (CNTs) for interconnects in future integrated circuits requires characterization techniques providing structural and electrical information at the nanometer scale. In this paper we present a slice-and-view approach based on electrical atomic force microscopy. Material removal achieved by successive scanning using doped ultra-sharp full-diamond probes, manufactured in-house, enables us to acquire two-dimensional (2D) resistance maps originating from different depths (equivalently different CNT lengths) on CNT-based interconnects. Stacking and interpolating these 2D resistance maps results in a three-dimensional (3D) representation (tomogram). This allows insight from a structural (e.g. size, density, distribution, straightness) and electrical point of view simultaneously. By extracting the resistance evolution over the length of an individual CNT we derive quantitative information about the resistivity and the contact resistance between the CNT and bottom electrode. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000306333500029 |
Publication Date |
2012-07-11 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.44 |
Times cited |
29 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.44; 2012 IF: 3.842 |
Call Number |
UA @ lucian @ c:irua:100750 |
Serial |
895 |
Permanent link to this record |
|
|
|
Author |
Narayanan, V.; Lommens, P.; De Buysser, K.; Vanpoucke, D.E.P.; Huehne, R.; Molina, L.; Van Tendeloo, G.; van der Voort, P.; Van Driessche, I. |
Title |
Aqueous CSD approach for the growth of novel, lattice-tuned LaxCe1-xO\delta epitaxial layers |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
Volume |
22 |
Issue |
17 |
Pages |
8476-8483 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Lanthanumcerium oxide (LCO) films were deposited on Ni-5%W substrates by chemical solution deposition (CSD) from water-based precursors. LCO films containing different ratios of lanthanum and cerium ions (from CeO2 to La2Ce2O7) were prepared. The composition of the layers was optimized towards the formation of LCO buffer layers, lattice-matched with the superconducting YBa2Cu3Oy layer, useful for the development of coated conductors. Single, crack-free LCO layers with a thickness of up to 140 nm could be obtained in a single deposition step. The crystallinity and microstructure of these lattice-matched LCO layers were studied by X-ray diffraction techniques, RHEED and SEM. We find that only layers with thickness below 100 nm show a crystalline top surface although both thick and thin layers show good biaxial texture in XRD. On the most promising layers, AFM and (S)TEM were performed to further evaluate their morphology. The overall surface roughness varies between 3.9 and 7.5 nm, while the layers appear much more dense than the frequently used La2Zr2O7 (LZO) systems, showing much smaller nanovoids (12 nm) than the latter system. Their effective buffer layer action was studied using XPS. The thin LCO layers supported the growth of superconducting YBCO deposited using PLD methods. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000302367500044 |
Publication Date |
2012-03-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
24 |
Open Access |
|
Notes |
Iap |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:96960 |
Serial |
148 |
Permanent link to this record |
|
|
|
Author |
Simon, Q.; Barreca, D.; Gasparotto, A.; Maccato, C.; Montini, T.; Gombac, V.; Fornasiero, P.; Lebedev, O.I.; Turner, S.; Van Tendeloo, G. |
Title |
Vertically oriented CuO/ZnO nanorod arrays : from plasma-assisted synthesis to photocatalytic H2 production |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of materials chemistry |
Abbreviated Journal |
J Mater Chem |
Volume |
22 |
Issue |
23 |
Pages |
11739-11747 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
1D CuO/ZnO nanocomposites were grown on Si(100) substrates by means of an original two-step synthetic strategy. ZnO nanorod (NR) arrays were initially deposited by plasma enhanced-chemical vapor deposition (PE-CVD) from an ArO2 atmosphere. Subsequently, tailored amounts of CuO were dispersed over zinc oxide matrices by radio frequency (RF)-sputtering of Cu from Ar plasmas, followed by thermal treatment in air. A thorough characterization of the obtained systems was carried out by 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 (FE-SEM), energy dispersive X-ray spectroscopy (EDXS), atomic force microscopy (AFM), transmission electron microscopy (TEM), electron diffraction (ED) and energy filtered-TEM (EF-TEM). Pure and highly oriented CuO/ZnO NR arrays, free from ternary ZnCuO phases and characterized by a copper(II) oxide content controllable as a function of the adopted RF-power, were successfully obtained. Interestingly, the structural relationships between the two oxides at the CuO/ZnO interface were found to depend on the overall CuO loading. The obtained nanocomposites displayed promising photocatalytic performances in H2 production by reforming of ethanolwater solutions under simulated solar illumination, paving the way to the sustainable conversion of solar light into chemical energy. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000304351400046 |
Publication Date |
2012-04-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0959-9428;1364-5501; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
74 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:98382 |
Serial |
3840 |
Permanent link to this record |
|
|
|
Author |
De Schepper, E.; Van Passel, S.; Manca, J.; Thewys, T. |
Title |
Combining photovoltaics and sound barriers : a feasibility study |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Renewable Energy |
Abbreviated Journal |
Renew Energ |
Volume |
46 |
Issue |
|
Pages |
297-303 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM) |
Abstract |
In the light of global warming, renewables such as solar photovoltaics (PV) are important to decrease greenhouse gas emissions. An important issue regarding implementation of solar panels on large scale, is the limited available area. Therefore, it can be interesting to combine PV with alternative applications, as a ways of not requiring “additional” space. One example is a photovoltaic noise barrier (PVNB), where a noise barrier located along a highway or railway is used as substructure for PV modules. Even though a PVNB is not a novel concept, the absence of economic assessments in literature can be a barrier to their wider implementation. In this paper, a feasibility study of a PVNB in Belgium is conducted, using a cost benefit analysis including a Monte Carlo sensitivity analysis. Besides purely economic aspects, also ecological benefits are monetized. The sensitivity analysis indicates that the ecological benefit of noise reduction, which is valuated using a noise sensitivity depreciation index applied to real estate prices, is of major importance in determining the net present value of the case study. On the contrary, the impact of reducing CO2 emissions seems to be negligible when expressed in monetary terms. The results suggest that the PVNB as a whole and also its separate components -.e. the PV array and the noise barrier can be profitable projects, when ecological benefits are included. (C) 2012 Elsevier Ltd. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000305169400036 |
Publication Date |
2012-04-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0960-1481 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.357 |
Times cited |
12 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 4.357; 2012 IF: 2.989 |
Call Number |
UA @ admin @ c:irua:127555 |
Serial |
6170 |
Permanent link to this record |
|
|
|
Author |
Witters, N.; Mendelsohn, R.; Van Passel, S.; Van Slycken, S.; Weyens, N.; Schreurs, E.; Meers, E.; Tack, F.; Vanheusden, B.; Vangronsveld, J. |
Title |
Phytoremediation, a sustainable remediation technology? 2 : economic assessment of CO2 abatement through the use of phytoremediation crops for renewable energy production |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Biomass & Bioenergy |
Abbreviated Journal |
Biomass Bioenerg |
Volume |
39 |
Issue |
|
Pages |
470-477 |
Keywords |
A1 Journal article; Economics; Engineering Management (ENM) |
Abstract |
Phytoremediation could be a sustainable remediation alternative for conventional remediation technologies. However, its implementation on a commercial scale remains disappointing. To emphasize its sustainability, this paper examines whether and how the potential economic benefit of CO2 abatement for different crops used for phytoremediation or sustainable land management purposes could promote phytotechnologies. Our analysis is based on a case study in the Campine region, where agricultural soils are contaminated with mainly cadmium. We use Life Cycle Analysis to show for the most relevant crops (willow (Salix spp), energy maize (Zea mays), and rapeseed (Brassica napus)), that phytoremediation, used for renewable energy production, could abate CO2. Converting this in economic numbers through the Marginal Abatement Cost of CO2 ( 20 ton−1) we can integrate this in the economic analysis to compare phytoremediation crops among each other, and phytoremediation with conventional technologies. The external benefit of CO2 abatement when using phytoremediation crops for land management ranges between 55 and 501 per hectare. The purpose of these calculations is not to calculate a subsidy for phytoremediation. There is no reason why one would prefer phytoremediation crops for renewable energy production over normal biomass. Moreover, subsidies for renewable energy already exist. Therefore, we should not integrate these numbers in the economic analysis again. However, these numbers could contribute to making explicit the competitive advantage of phytoremediation compared to conventional remediation technologies, but also add to a more sustainably funded decision on which crop should be grown on contaminated land. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000302829900054 |
Publication Date |
2011-12-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0961-9534 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.219 |
Times cited |
38 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 3.219; 2012 IF: 2.975 |
Call Number |
UA @ admin @ c:irua:129863 |
Serial |
6236 |
Permanent link to this record |
|
|
|
Author |
Van Dael, M.; Van Passel, S.; Pelkmans, L.; Guisson, R.; Swinnen, G.; Schreurs, E. |
Title |
Determining potential locations for biomass valorization using a macro screening approach |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Biomass & Bioenergy |
Abbreviated Journal |
Biomass Bioenerg |
Volume |
45 |
Issue |
|
Pages |
175-186 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Engineering Management (ENM) |
Abstract |
European policy states that by 2020 at least 20% of final energy consumption should come from renewable energy sources. Biomass as a renewable energy source cannot be disregarded in order to attain this target. In this study a macro screening approach is developed to determine potential locations for biomass valorization in a specified region. The approach consists of five steps: (1) criteria determination, (2) data gathering, (3) weight assignment, (4) final score, (5) spatial representation. The resulting outcome provides a first well balanced scan of the possibilities for energy production using regional biomass. This way policy makers and investors can be supported and motivated to study the possibilities of building energy production plants at specific locations in more detail, which can be described as a 'micro-screening'. In our case study the approach is applied to determine the potentially interesting locations to establish a biomass project. The region has been limited to the forty-four communities in the province of Limburg (Belgium). The macro screening approach has shown to be very effective since the amount of interesting locations has been reduced drastically. (c) 2012 Elsevier Ltd. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000308384500019 |
Publication Date |
2012-06-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0961-9534 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.219 |
Times cited |
23 |
Open Access |
|
Notes |
; The authors gratefully acknowledge the financial support from INTERREG and the province of Limburg. Special thanks to our colleague Thomas Voets for his effort in making the GIS maps. Moreover, the authors would like to thank the two anonymous reviewers for their valuable comments. ; |
Approved |
Most recent IF: 3.219; 2012 IF: 2.975 |
Call Number |
UA @ admin @ c:irua:127554 |
Serial |
6178 |
Permanent link to this record |
|
|
|
Author |
Zhao, S.-X.; Gao, F.; Wang, Y.-N.; Bogaerts, A. |
Title |
The effect of F2 attachment by low-energy electrons on the electron behaviour in an Ar/CF4 inductively coupled plasma |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
Volume |
21 |
Issue |
2 |
Pages |
025008-025008,13 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The electron behaviour in an Ar/CF4 inductively coupled plasma is investigated by a Langmuir probe and a hybrid model. The simulated and measured results include electron density, temperature and electron energy distribution function for different values of Ar/CF4 ratio, coil power and gas pressure. The hybrid plasma equipment model simulations show qualitative agreement with experiment. The effect of F2 electron attachment on the electron behaviour is explored by comparing two sets of data based on different F atom boundary conditions. It is demonstrated that electron attachment at F2 molecules is responsible for the depletion of low-energy electrons, causing a density decrease as well as a temperature increase when CF4 is added to an Ar plasma. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000302779400022 |
Publication Date |
2012-03-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.302 |
Times cited |
23 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.302; 2012 IF: 2.515 |
Call Number |
UA @ lucian @ c:irua:96549 |
Serial |
841 |
Permanent link to this record |
|
|
|
Author |
Xu, Q.; Zandbergen, H.W.; van Dyck, D. |
Title |
Imaging from atomic structure to electronic structure |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Micron |
Abbreviated Journal |
Micron |
Volume |
43 |
Issue |
4 |
Pages |
524-531 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
This paper discusses the possibility of retrieving the electron distribution (with highlighted valence electron distribution information) of materials from recorded HREM images. This process can be achieved by solving two inverse problems: reconstruction of the exit wave and reconstruction of the electron distribution from exit waves. The first inverse problem can be solved using a focal series reconstruction method. We show that the second inverse problem can be solved by combining a series of exit waves recorded at different thickness conditions. This process is designed based on an improved understanding of the dynamical scattering process. It also explains the fundamental difficulty of obtaining the valence electron distribution information and the basis of our solution. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000301702400005 |
Publication Date |
2011-11-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0968-4328; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
1.98 |
Times cited |
|
Open Access |
|
Notes |
Fwo |
Approved |
Most recent IF: 1.98; 2012 IF: 1.876 |
Call Number |
UA @ lucian @ c:irua:93634 |
Serial |
1553 |
Permanent link to this record |
|
|
|
Author |
Van Aert, S.; van den Broek, W.; Goos, P.; van Dyck, D. |
Title |
Model-based electron microscopy : from images toward precise numbers for unknown structure parameters |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Micron |
Abbreviated Journal |
Micron |
Volume |
43 |
Issue |
4 |
Pages |
509-515 |
Keywords |
A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
Statistical parameter estimation theory is proposed as a method to quantify electron microscopy images. It aims at obtaining precise and accurate values for the unknown structure parameters including, for example, atomic column positions and types. In this theory, observations are purely considered as data planes, from which structure parameters have to be determined using a parametric model describing the images. The method enables us to measure positions of atomic columns with a precision of the order of a few picometers even though the resolution of the electron microscope is one or two orders of magnitude larger. Moreover, small differences in averaged atomic number, which cannot be distinguished visually, can be quantified using high-angle annular dark field scanning transmission electron microscopy images. Finally, it is shown how to optimize the experimental design so as to attain the highest precision. As an example, the optimization of the probe size for nanoparticle radius measurements is considered. It is also shown how to quantitatively balance signal-to-noise ratio and resolution by adjusting the probe size. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000301702400003 |
Publication Date |
2011-11-03 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
0968-4328; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.98 |
Times cited |
7 |
Open Access |
|
Notes |
Fwo |
Approved |
Most recent IF: 1.98; 2012 IF: 1.876 |
Call Number |
UA @ lucian @ c:irua:94114 |
Serial |
2099 |
Permanent link to this record |
|
|
|
Author |
Tirry, W.; Bouvier, S.; Benmhenni, N.; Hammami, W.; Habraken, A.M.; Coghe, F.; Schryvers, D.; Rabet, L. |
Title |
Twinning in pure Ti subjected to monotonic simple shear deformation |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Materials characterization |
Abbreviated Journal |
Mater Charact |
Volume |
72 |
Issue |
|
Pages |
24-36 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The aim of this paper is to provide a thorough study on the occurrence and importance of deformation twinning in simple shear deformed pure α-Ti. A statistically relevant inspection of the morphology of the deformation twins in relation to the applied strain/deformation is performed. The investigated microstructural aspects are the twin volume fraction, the twin thickness distribution and the resolved shear stress distribution on the twin plane. All these aspects are examined as a function of the twin types and two initial textures. Monotonic simple shear experiments are carried out for three different loading directions with respect to a direction linked to the initial crystallographic texture. EBSD and TEM observations reveal the presence of View the MathML source and View the MathML source twins. The statistical analysis reveals that View the MathML source and View the MathML source twins have a similar average thickness around 1.9 nm, but the View the MathML source twins show a far larger spread on their thickness and can grow to almost the size of the original parent grain. Correlation of the twin fractions with the RSS analysis shows that RSS is an acceptable method explaining the difference in twin fractions for different textures and orientations. A detailed analysis shows that View the MathML source twins occur in average with a smaller volume fraction but with a higher RSS, indicating they are more difficult to nucleate or grow compared to View the MathML source twinning. In general a higher RSS value on the twin plane is not connected to a higher twin thickness; only in the case of View the MathML source twins the highest RSS values show clearly thicker twins. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York |
Editor |
|
Language |
|
Wos |
000309086700004 |
Publication Date |
2012-07-10 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1044-5803; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.714 |
Times cited |
25 |
Open Access |
|
Notes |
Iap |
Approved |
Most recent IF: 2.714; 2012 IF: 1.880 |
Call Number |
UA @ lucian @ c:irua:101225 |
Serial |
3768 |
Permanent link to this record |
|
|
|
Author |
Shanenko, A.A.; Croitoru, M.D.; Vagov, A.V.; Axt, V.M.; Perali, A.; Peeters, F.M. |
Title |
Atypical BCS-BEC crossover induced by quantum-size effects |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : A : atomic, molecular and optical physics |
Abbreviated Journal |
Phys Rev A |
Volume |
86 |
Issue |
3 |
Pages |
033612 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Quantum-size oscillations of the basic physical characteristics of a confined fermionic condensate are a well-known phenomenon. Its conventional understanding is based on the single-particle physics, whereby the oscillations follow variations in the single-particle density of states driven by the size quantization. Here we present a study of a cigar-shaped ultracold superfluid Fermi gas, which demonstrates an important many-body aspect of the quantum-size coherent effects, overlooked previously. The many-body physics is revealed here in the atypical crossover from the Bardeen-Cooper-Schrieffer (BCS) superfluid to the Bose-Einstein condensate (BEC) induced by the size quantization of the particle motion. The single-particle energy spectrum for the transverse dimensions is tightly bound, whereas for the longitudinal direction it resembles a quasi-free dispersion. This results in the formation of a series of single-particle subbands (shells) so that the aggregate fermionic condensate becomes a coherent mixture of subband condensates. Each time when the lower edge of a subband crosses the chemical potential, the BCS-BEC crossover is approached in this subband, and the aggregate condensate contains both BCS and BEC-like components. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
Language |
|
Wos |
000308639500004 |
Publication Date |
2012-09-15 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1050-2947;1094-1622; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.925 |
Times cited |
34 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). The authors thank C. Salomon and C. Vale for their valuable explications of the experimental situation and interest to our work. We are grateful to G. C. Strinati, D. Neilson, and P. Pieri for useful discussions. M. D. C. acknowledges support of the EU Marie Curie IEF Action (Grant Agreement No. PIEF-GA-2009-235486-ScQSR). A. P. gratefully acknowledges financial support of the European Science Foundation, POLATOM Research Networking Programme, Ref. No. 4844 for his visit to the University of Antwerp. A. A. S. acknowledges financial support of the European Science Foundation, POLATOM Research Networking Programme, Ref. No. 5200 for his visit to the University of Camerino. ; |
Approved |
Most recent IF: 2.925; 2012 IF: 3.042 |
Call Number |
UA @ lucian @ c:irua:101844 |
Serial |
203 |
Permanent link to this record |
|
|
|
Author |
Matulis, A.; Masir, M.R.; Peeters, F.M. |
Title |
Scattering of a Dirac electron on a mass barrier |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : A : atomic, molecular and optical physics |
Abbreviated Journal |
Phys Rev A |
Volume |
86 |
Issue |
2 |
Pages |
022101 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The interaction of a wave packet (and in particular the wave front) with a mass barrier is investigated in one dimension. We discuss the main features of the wave packet that are inherent to two-dimensional wave packets, such as compression during reflection, penetration in the case when the energy is lower than the height of the barrier, waving tails, precursors, and the retardation of the reflected and penetrated wave packets. These features depend on the wave-packet envelope function which we demonstrate by considering the case of a rectangular wave packet with sharp front and trailing edges and a smooth Gaussian wave packet. The method of Fourier integral for obtaining the nonstationary solutions is used. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000306991200001 |
Publication Date |
2012-08-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1050-2947;1094-1622; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.925 |
Times cited |
9 |
Open Access |
|
Notes |
; This research was supported by the Flemish Science Foundation (FWO-Vl) and (in part) by the Lithuanian Science Council under Project No. MIP-79/2010. ; |
Approved |
Most recent IF: 2.925; 2012 IF: 3.042 |
Call Number |
UA @ lucian @ c:irua:100822 |
Serial |
2948 |
Permanent link to this record |
|
|
|
Author |
Matsubara, M.; Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B. |
Title |
Attracting shallow donors : hydrogen passivation in (Al,Ga,In)-doped ZnO |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
86 |
Issue |
16 |
Pages |
165207 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
The hydrogen interstitial and the substitutional AlZn, GaZn, and InZn are all shallow donors in ZnO and lead to n-type conductivity. Although shallow donors are expected to repel each other, we show by first-principles calculations that in ZnO these shallow donor impurities attract and form a complex, leading to a donor level deep in the band gap. This puts a limit on the n-type conductivity of (Al,Ga,In)-doped ZnO in the presence of hydrogen. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000310131300008 |
Publication Date |
2012-10-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
7 |
Open Access |
|
Notes |
Iwt; Fwo; Bof-Noi |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
Call Number |
UA @ lucian @ c:irua:101780 |
Serial |
202 |
Permanent link to this record |
|
|
|
Author |
Rønnow, T.F.; Pedersen, T.G.; Partoens, B. |
Title |
Biexciton binding energy in fractional dimensional semiconductors |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
85 |
Issue |
4 |
Pages |
045412-045412,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Biexcitons in fractional dimensional spaces are studied using variational quantum Monte Carlo. We investigate the biexciton binding energy as a function of the electron-hole mass fraction sigma as well as study the dimensional dependence of biexcitons for sigma = 0 and sigma = 1. As our first application of this model we treat the H(2) molecule in two and three dimensions. Next we investigate biexcitons in carbon nanotubes within the fractional dimensional model. To this end we find a relation between the nanotube radius and the effective dimension. The results of both applications are compared with results obtained using different models and we find a reasonable agreement. Within the fractional dimensional model we find that the biexciton binding energy in carbon nanotubes accurately scales as E(B)(r,epsilon) = 1280 meV angstrom/(r epsilon), as a function of radius r and the dielectric screening epsilon. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000298922200008 |
Publication Date |
2012-01-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
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; 2012 IF: 3.767 |
Call Number |
UA @ lucian @ c:irua:96234 |
Serial |
231 |
Permanent link to this record |
|
|
|
Author |
Sena, S.H.R.; Pereira, J.M.; Farias, G.A.; Peeters, F.M. |
Title |
Cyclotron resonance of trilayer graphene |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
86 |
Issue |
8 |
Pages |
085412 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The cyclotron resonance energies, the corresponding oscillator strengths, and the cyclotron absorption spectrum for trilayer graphene are calculated for both ABA and ABC stacking. A gate potential across the stacked layers leads to (1) a reduction of the transition energies, (2) a lifting of the degeneracy of the zero Landau level, and (3) the removal of the electron-hole symmetry. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000307273100009 |
Publication Date |
2012-08-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
7 |
Open Access |
|
Notes |
; This work was supported by the National Council for the Improvement of Higher education (CAPES), the Brazilian Council for Research (CNPq), the Flemish Science Foundation (FWO-V1), the bilateral projects between Flanders and Brazil and the CNPq and FWO-V1, and the ESF-Eurographene project CONGRAN. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
Call Number |
UA @ lucian @ c:irua:100815 |
Serial |
604 |
Permanent link to this record |
|
|
|
Author |
Badalyan, S.M.; Peeters, F.M. |
Title |
Effect of nonhomogenous dielectric background on the plasmon modes in graphene double-layer structures at finite temperatures |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
85 |
Issue |
19 |
Pages |
195444-195444,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We have calculated the plasmon modes in graphene double layer structures at finite temperatures, taking into account the inhomogeneity of the dielectric background of the system. The effective dielectric function is obtained from the solution of the Poisson equation of a three-layer dielectric medium with graphene sheets located at the interfaces, separating the different materials. Due to the momentum dispersion of the effective dielectric function, the intra- and interlayer bare Coulomb interactions in the graphene double layer system acquires an additional momentum dependence-an effect that is of the order of the interlayer interaction itself. We show that the energies of the in-phase and out-of-phase plasmon modes are determined largely by different values of the spatially dependent effective dielectric function. The effect of the dielectric inhomogeneity increases with temperature, and even at high temperatures the energy shift induced by the dielectric inhomogeneity and temperature itself remains larger than the broadening of the plasmon energy dispersions due to the Landau damping. The obtained new features of the plasmon dispersions can be observed in frictional drag measurements and in inelastic light scattering and electron energy-loss spectroscopies. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000304394800011 |
Publication Date |
2012-05-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
67 |
Open Access |
|
Notes |
; We thank G. Vignale for useful discussions and acknowledge support from the Flemisch Science Foundation (FWO-Fl) and the Belgian Science Policy (BELSPO). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
Call Number |
UA @ lucian @ c:irua:98941 |
Serial |
826 |
Permanent link to this record |
|
|
|
Author |
Lipavsky, P.; Elmurodov, A.; Lin, P.-J.; Matlock, P.; Berdiyorov, G.R. |
Title |
Effect of normal current corrections on the vortex dynamics in type-II superconductors |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
86 |
Issue |
14 |
Pages |
144516-144518 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Within the time-dependent Ginzburg-Landau theory we discuss the effect of nonmagnetic interactions between the normal current and supercurrent in the presence of electric and magnetic fields. The correction due to the current-current interactions is shown to have a transient character so that it contributes only when a system evolves. Numerical studies for thin current-carrying superconducting strips with no magnetic feedback show that the effect of the normal current corrections is more pronounced in the resistive state where fast-moving kinematic vortices are formed. Simulations also reveal that the largest contribution due to current-current interactions appears near the sample edges, where the vortices reach their maximal velocity. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000309809700007 |
Publication Date |
2012-10-15 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
4 |
Open Access |
|
Notes |
; The authors are grateful to Alex Gurevich and Tom Lemberger who brought the longitudinal f-sum rule to our attention. This work was supported by Grants GACR P204/10/0687 and P204/11/0015. We also acknowledge the support from the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). G.R.B. acknowledges individual support from FWO-Vl. P.-J.L. acknowledges support from Old Dominion University. P.M. acknowledges support through UA research index SR-614-1203. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
Call Number |
UA @ lucian @ c:irua:102168 |
Serial |
827 |
Permanent link to this record |
|
|
|
Author |
Shakouri, K.; Szafran, B.; Esmaeilzadeh, M.; Peeters, F.M. |
Title |
Effective spin-orbit interaction Hamiltonian for quasi-one-dimensional quantum rings |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
85 |
Issue |
16 |
Pages |
165314-165314,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The effective Hamiltonian for an electron in a quasi-one-dimensional quantum ring in the presence of spin-orbit interactions is derived. We demonstrate that, when both coupling types are simultaneously present, the effective Hamiltonian derived by the lowest-radial-state approximation produces energy spectra and charge densities which deviate strongly from the exact ones. For equal Rashba and Dresselhaus coupling constants the lowest-radial-state approximation opens artifactal avoided crossings in the energy spectra and deforms the circular symmetry of the confined charge densities. In this case, there does not exist a ring thin enough to justify the restriction to the lowest radially quantized energy state. We derive the effective Hamiltonian accounting for both the lowest and the first excited radial states, and show that the inclusion of the latter restores the correct features of the exact solution. Relation of this result to the states of a quantum wire is also discussed. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000303068800006 |
Publication Date |
2012-04-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
32 |
Open Access |
|
Notes |
; This work was partially supported by Polish Ministry of Science and Higher Education and its grants for Scientific Research. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
Call Number |
UA @ lucian @ c:irua:98258 |
Serial |
855 |
Permanent link to this record |
|
|
|
Author |
Nasr Esfahani, D.; Covaci, L.; Peeters, F.M. |
Title |
Electric-field-induced shift of the Mott metal-insulator transition in thin films |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
85 |
Issue |
8 |
Pages |
085110-085110,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The ground-state properties of a paramagnetic Mott insulator at half-filling are investigated in the presence of an external electric field using the inhomogeneous Gutzwiller approximation for a single-band Hubbard model in a slab geometry. We find that the metal-insulator transition is shifted toward higher Hubbard repulsions by applying an electric field perpendicular to the slab. The main reason is the accumulation of charges near the surface. The spatial distribution of site-dependent quasiparticle weight shows that it is maximal in a few layers beneath the surface, while the central sites where the field is screened have a very low quasiparticle weight. Our results show that above a critical-field value, states near the surface will be metallic, while the bulk quasiparticle weight is extremely suppressed but never vanishing, even for large Hubbard repulsions above the bulk zero-field critical value. Below the critical-field value, our results hint toward an insulating state in which the electric field is totally screened and the slab is again at half-filling. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000300240100002 |
Publication Date |
2012-02-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN ![sorted by ISSN field, ascending order (up)](img/sort_asc.gif) |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
3 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
Call Number |
UA @ lucian @ c:irua:97208 |
Serial |
884 |
Permanent link to this record |