| Records |
| Author |
Wang, H.; Cuppens, J.; Biermans, E.; Bals, S.; Fernandez-Ballester, L.; Kvashnina, K.O.; Bras, W.; van Bael, M.J.; Temst, K.; Vantomme, A. |
| Title |
Tuning of the size and the lattice parameter of ion-beam synthesized Pb nanoparticles embedded in Si |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
| Volume |
45 |
Issue |
3 |
Pages |
035301-035301,7 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The size and lattice constant evolution of Pb nanoparticles (NPs) synthesized by high fluence implantation in crystalline Si have been studied with a variety of experimental techniques. Results obtained from small-angle x-ray scattering showed that the Pb NPs grow with increasing implantation fluence and annealing duration. The theory of NP growth kinetics can be applied to qualitatively explain the size evolution of the Pb NPs during the implantation and annealing processes. Moreover, the lattice constant of the Pb NPs was evaluated by conventional x-ray diffraction. The lattice dilatation was observed to decrease with increasing size of the Pb NPs. Such lattice constant tuning can be attributed to the pseudomorphism caused by the lattice mismatch between the Pb NPs and the Si matrix. |
| Address |
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| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication  |
London |
Editor |
|
| Language |
|
Wos |
000299308400008 |
Publication Date |
2011-12-23 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0022-3727;1361-6463; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.588 |
Times cited |
5 |
Open Access |
|
| Notes |
Fwo; Iap |
Approved |
Most recent IF: 2.588; 2012 IF: 2.528 |
| Call Number |
UA @ lucian @ c:irua:94208 |
Serial |
3754 |
| Permanent link to this record |
| |
|
| |
| Author |
Rosova, A.; Krekels, T.; Van Tendeloo, G.; Darriet, B.; Chambon, M. |
| Title |
Twin boundary structure of Au-doped YBa2Cu3O7-x single crystals |
Type |
A1 Journal article |
| Year |
1993 |
Publication |
Ferroelectrics |
Abbreviated Journal |
Ferroelectrics |
| Volume |
141 |
Issue |
|
Pages |
87-94 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
|
Publication Date |
0000-00-00 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0015-0193 |
ISBN |
|
Additional Links |
UA library record |
| Impact Factor |
0.469 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
no |
| Call Number |
UA @ lucian @ c:irua:7502 |
Serial |
3766 |
| Permanent link to this record |
| |
|
| |
| Author |
Ferreira, W.P.; Farias, G.A.; Peeters, F.M. |
| Title |
A two-component mixture of charged particles confined in a channel: melting |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
| Volume |
22 |
Issue |
28 |
Pages |
11 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The melting of a binary system of charged particles confined in a quasi-one-dimensional parabolic channel is studied through Monte Carlo simulations. At zero temperature the particles are ordered in parallel chains. The melting is anisotropic and different melting temperatures are obtained according to the spatial direction, and the different kinds of particles present in the system. Melting is very different for the single-, two- and four-chain configurations. A temperature induced structural phase transition is found between two different four-chain ordered states which is absent in the mono-disperse system. In the mixed regime, where the two kinds of particles are only slightly different, melting is almost isotropic and a thermally induced homogeneous distribution of the distinct kinds of charges is observed. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000279257300023 |
Publication Date |
2010-06-16 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.649 |
Times cited |
10 |
Open Access |
|
| Notes |
; This work was supported by CNPq, the Flemish Science Foundation (FWO-V1) and the bilateral program between Flanders and Brazil. ; |
Approved |
Most recent IF: 2.649; 2010 IF: 2.332 |
| Call Number |
UA @ lucian @ c:irua:83862 |
Serial |
3771 |
| 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 |
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 |
Pereira, J.M.; Peeters, F.M.; Costa Filho, R.N.; Farias, G.A. |
| Title |
Valley polarization due to trigonal warping on tunneling electrons in graphene |
Type |
A1 Journal article |
| Year |
2009 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
| Volume |
21 |
Issue |
4 |
Pages |
045301,1-045301,4 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The effect of trigonal warping on the transmission of electrons tunneling through potential barriers in graphene is investigated. We present calculations of the transmission coefficient for single and double barriers as a function of energy, incidence angle and barrier heights. The results show remarkable valley-dependent directional effects for barriers oriented parallel to the armchair or parallel to the zigzag direction. These results indicate that electrostatic gates can be used as valley filters in graphene-based devices. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000262354700004 |
Publication Date |
2008-12-20 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.649 |
Times cited |
78 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.649; 2009 IF: 1.964 |
| Call Number |
UA @ lucian @ c:irua:75736 |
Serial |
3834 |
| Permanent link to this record |
| |
|
| |
| Author |
Xu, W.; Peeters, F.M.; Devreese, J.T. |
| Title |
Warm-electron transport in a two-dimensional semiconductor |
Type |
A1 Journal article |
| Year |
1992 |
Publication |
Semiconductor science and technology |
Abbreviated Journal |
Semicond Sci Tech |
| Volume |
7 |
Issue |
|
Pages |
1251-1256 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
| Abstract |
|
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
A1992JT73000006 |
Publication Date |
0000-00-00 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0268-1242 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.19 |
Times cited |
3 |
Open Access |
|
| Notes |
|
Approved |
no |
| Call Number |
UA @ lucian @ c:irua:2915 |
Serial |
3903 |
| Permanent link to this record |
| |
|
| |
| Author |
Rakhimov, K.Y.; Chaves, A.; Farias, G.A.; Peeters, F.M. |
| Title |
Wavepacket scattering of Dirac and Schrödinger particles on potential and magnetic barriers |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
| Volume |
23 |
Issue |
27 |
Pages |
275801,1-275801,16 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We investigate the dynamics of a charged particle moving in a graphene layer and in a two-dimensional electron gas, where it obeys the Dirac and the Schrödinger equations, respectively. The charge carriers are described as Gaussian wavepackets. The dynamics of the wavepackets is studied numerically by solving both quantum-mechanical and relativistic equations of motion. The scattering of such wavepackets by step-like magnetic and potential barriers is analysed for different values of wavepacket energy and width. We find: (1) that the average position of the wavepacket does not coincide with the classical trajectory, and (2) that, for slanted incidence, the path of the centre of mass of the wavepacket does not have to penetrate the barrier during the scattering process. Trembling motion of the charged particle in graphene is observed in the absence of an external magnetic field and can be enhanced by a substrate-induced mass term. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000291993600009 |
Publication Date |
2011-06-18 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.649 |
Times cited |
32 |
Open Access |
|
| Notes |
; Discussions with A Matulis are gratefully acknowledged. KR is beneficiary of a mobility grant from the Belgian Federal Science Policy Office, co-funded by the European Commission and was supported in part by a grant of the Third World Academy of Sciences (ref. 09-188 RG/PHYS/AS-I). In addition, this work was financially supported by CNPq, under contract NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES, the Bilateral programme between Flanders and Brazil, the joint project CNPq-FWO, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 2.649; 2011 IF: 2.546 |
| Call Number |
UA @ lucian @ c:irua:90880 |
Serial |
3908 |
| Permanent link to this record |
| |
|
| |
| Author |
Sivek, J.; Sahin, H.; Partoens, B.; Peeters, F.M. |
| Title |
Giant magnetic anisotropy in doped single layer molybdenum disulfide and fluorographene |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
| Volume |
28 |
Issue |
28 |
Pages |
195301 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Stable monolayer materials based on existing, well known and stable two-dimensional crystal fluorographene and molybdenum disulfide are predicted to exhibit a huge magnetocrystalline anisotropy when functionalized with adsorbed transition metal atoms at vacant sides. Ab initio calculations within the density-functional theory formalism were performed to investigate the adsorption of the transitional metals in a single S (or F) vacancy of monolayer molybdenum disulfide (or fluorographene). We found strong bonding of the transitional metal atoms to the vacant sites with binding energies ranging from 2.5 to 5.2 eV. Our calculations revealed that these systems with adsorbed metal atoms exhibit a magnetic anisotropy, specifically the structures including Os and Ir show a giant magnetocrystalline anisotropy energy of 31-101 meV. Our results demonstrate the possibility of obtaining stable monolayer materials with huge magnetocrystalline anisotropy based on preexisting, well known and stable two-dimensional crystals: fluorographene and molybdenum disulfide. We believe that the results obtained here are useful not only for deeper understanding of the origin of magnetocrystalline anisotropy but also for the design of monolayer optoelectronic devices with novel functionalities. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000374394700007 |
Publication Date |
2016-04-13 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.649 |
Times cited |
7 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.649 |
| Call Number |
UA @ lucian @ c:irua:133611 |
Serial |
4185 |
| Permanent link to this record |
| |
|
| |
| Author |
Zarenia, M.; Perali, A.; Peeters, F.M.; Neilson, D. |
| Title |
Large gap electron-hole superfluidity and shape resonances in coupled graphene nanoribbons |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
| Volume |
6 |
Issue |
6 |
Pages |
24860 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
We predict enhanced electron-hole superfluidity in two coupled electron-hole armchair-edge terminated graphene nanoribbons separated by a thin insulating barrier. In contrast to graphene monolayers, the multiple subbands of the nanoribbons are parabolic at low energy with a gap between the conduction and valence bands, and with lifted valley degeneracy. These properties make screening of the electron-hole interaction much weaker than for coupled electron-hole monolayers, thus boosting the pairing strength and enhancing the superfluid properties. The pairing strength is further boosted by the quasi one-dimensional quantum confinement of the carriers, as well as by the large density of states near the bottom of each subband. The latter magnifies superfluid shape resonances caused by the quantum confinement. Several superfluid partial condensates are present for finite-width nanoribbons with multiple subbands. We find that superfluidity is predominately in the strongly-coupled BEC and BCS-BEC crossover regimes, with large superfluid gaps up to 100 meV and beyond. When the gaps exceed the subband spacing, there is significant mixing of the subbands, a rounding of the shape resonances, and a resulting reduction in the one-dimensional nature of the system. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000374654500002 |
Publication Date |
2016-04-25 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.259 |
Times cited |
7 |
Open Access |
|
| Notes |
; M.Z. acknowledges support by the Flemish Science Foundation (FWO-Vl), the University Research Fund (BOF), and the European Science Foundation (POLATOM). A.P. and D.N. acknowledge support by the University of Camerino FAR project CESEMN. The authors thank the colleagues involved in the MultiSuper International Network (http://www.multisuper.org) for exchange of ideas and suggestions for this work. ; |
Approved |
Most recent IF: 4.259 |
| Call Number |
UA @ lucian @ c:irua:133619 |
Serial |
4201 |
| Permanent link to this record |
| |
|
| |
| Author |
Croitoru, M.D.; Shanenko, A.A.; Vagov, A.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. |
| Title |
Phonon limited superconducting correlations in metallic nanograins |
Type |
A1 Journal article |
| Year |
2015 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
| Volume |
5 |
Issue |
5 |
Pages |
16515 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
Conventional superconductivity is inevitably suppressed in ultra-small metallic grains for characteristic sizes smaller than the Anderson limit. Experiments have shown that above the Anderson limit the critical temperature may be either enhanced or reduced when decreasing the particle size, depending on the superconducting material. In addition, there is experimental evidence that whether an enhancement or a reduction is found depends on the strength of the electronphonon interaction in the bulk. We reveal how the strength of the e-ph interaction interplays with the quantum-size effect and theoretically obtain the critical temperature of the superconducting nanograins in excellent agreement with experimental data. We demonstrate that strong e-ph scattering smears the peak structure in the electronic density-of-states of a metallic grain and enhances the electron mass, and thereby limits the highest T-c achievable by quantum confinement. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000364647700001 |
Publication Date |
2015-11-13 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.259 |
Times cited |
9 |
Open Access |
|
| Notes |
; This work was supported by the Belgian Science Policy (BELSPO Back to Belgium Grant), the Research Foundation Flanders (FWO), the Methusalem Foundation of the Flemish Government, TOPBOF-UA, and the bilateral project CNPq-FWO. M.D.C. acknowledges fruitful discussions with V. Z. Kresin, S. N. Klimin and V. N. Gladilin. ; |
Approved |
Most recent IF: 4.259; 2015 IF: 5.578 |
| Call Number |
UA @ lucian @ c:irua:129543 |
Serial |
4224 |
| Permanent link to this record |
| |
|
| |
| Author |
Ryabova, A.S.; Napolskiy, F.S.; Poux, T.; Istomin, S.Y.; Bonnefont, A.; Antipin, D.M.; Baranchikov, A.Y.; Levin, E.E.; Abakumov, A.M.; Kéranguéven, G.; Antipov, E.V.; Tsirlina, G.A.; Savinova, E.R.; |
| Title |
Rationalizing the influence of the Mn(IV)/Mn(III) red-Ox transition on the electrocatalytic activity of manganese oxides in the oxygen reduction reaction |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Electrochimica acta |
Abbreviated Journal |
Electrochim Acta |
| Volume |
187 |
Issue |
187 |
Pages |
161-172 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Knowledge on the mechanisms of oxygen reduction reaction (ORR) and descriptors linking the catalytic activity to the structural and electronic properties of transition metal oxides enable rational design of more efficient catalysts. In this work ORR electrocatalysis was studied on a set of single and complex Mn (III) oxides with a rotating disc electrode method and cyclic voltammetry. We discovered an exponential increase of the specific electrocatalytic activity with the potential of the surface Mn(IV)/Mn(III) red-ox couple, suggesting the latter as a new descriptor for the ORR electrocatalysis. The observed dependence is rationalized using a simple mean-field kinetic model considering availability of the Mn( III) centers and adsorbate-adsorbate interactions. We demonstrate an unprecedented activity of Mn2O3, ca. 40 times exceeding that of MnOOH and correlate the catalytic activity of Mn oxides to their crystal structure. (C) 2015 Elsevier Ltd. All rights reserved. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000367235600019 |
Publication Date |
2015-11-10 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0013-4686 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.798 |
Times cited |
51 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 4.798 |
| Call Number |
UA @ lucian @ c:irua:131096 |
Serial |
4237 |
| Permanent link to this record |
| |
|
| |
| Author |
Curran, P.J.; Desoky, W.M.; Milošević, M.V.; Chaves, A.; Laloe, J.-B.; Moodera, J.S.; Bending, S.J. |
| Title |
Spontaneous symmetry breaking in vortex systems with two repulsive lengthscales |
Type |
A1 Journal article |
| Year |
2015 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
| Volume |
5 |
Issue |
5 |
Pages |
15569 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
Scanning Hall probe microscopy (SHPM) has been used to study vortex structures in thin epitaxial films of the superconductor MgB2. Unusual vortex patterns observed in MgB2 single crystals have previously been attributed to a competition between short-range repulsive and long-range attractive vortex-vortex interactions in this two band superconductor; the type 1.5 superconductivity scenario. Our films have much higher levels of disorder than bulk single crystals and therefore both superconducting condensates are expected to be pushed deep into the type 2 regime with purely repulsive vortex interactions. We observe broken symmetry vortex patterns at low fields in all samples after field-cooling from above T-c. These are consistent with those seen in systems with competing repulsions on disparate length scales, and remarkably similar structures are reproduced in dirty two band Ginzburg-Landau calculations, where the simulation parameters have been defined by experimental observations. This suggests that in our dirty MgB2 films, the symmetry of the vortex structures is broken by the presence of vortex repulsions with two different lengthscales, originating from the two distinct superconducting condensates. This represents an entirely new mechanism for spontaneous symmetry breaking in systems of superconducting vortices, with important implications for pinning phenomena and high current density applications. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000363306000002 |
Publication Date |
2015-10-23 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.259 |
Times cited |
12 |
Open Access |
|
| Notes |
; P.J.C. and S.J.B. acknowledge support from EPSRC in the UK under grant number EP/J010626/1 and the NanoSC COST Action MP-1201. M.V.M. thanks the Research Foundation-Flanders (FWO) and CAPES Brazil. A.C. acknowledges the financial support of CNPq, under the PRONEX/FUNCAP and PQ programs. J.-B.L. and J.S.M. acknowledge ONR Grant N00014-06-01-0235. ; |
Approved |
Most recent IF: 4.259; 2015 IF: 5.578 |
| Call Number |
UA @ lucian @ c:irua:129450 |
Serial |
4248 |
| Permanent link to this record |
| |
|
| |
| Author |
Charkin, D.O.; Akinfiev, V.S.; Alekseeva, A.M.; Batuk, M.; Abakumov, A.M.; Kazakov, S.M. |
| Title |
Synthesis and cation distribution in the new bismuth oxyhalides with the Sillen-Aurivillius intergrowth structures |
Type |
A1 Journal article |
| Year |
2015 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
Dalton T |
| Volume |
44 |
Issue |
44 |
Pages |
20568-20576 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
About 20 new compounds with the Sillen-Aurivillius intergrowth structure, (MeMeBi3Nb2O11X)-Me-1-Bi-2 (Me-1 = Pb, Sr, Ba; Me-2 = Ca, Sr, Ba; X = Cl, Br, I), have been prepared. They are composed of stacking of [ANb(2)O(7)] perovskite blocks, fluorite-type [M2O2] blocks and halogen sheets. The cation distribution between the fluorite and perovskite layers has been studied for Ba2Bi3Nb2O11I, Ca1.25Sr0.75Bi3Nb2O11Cl, BaCaBi3Nb2O11Br and Sr2Bi3Nb2O11Cl. The smaller Me cations tend to reside in the perovskite block while the larger ones are situated in the fluorite-type block. The distribution of the elements was confirmed for BaCaBi3Nb2O11Br using energy dispersive X-ray analysis combined with scanning transmission electron microscopy (STEM-EDX). An electron diffraction study of this compound reveals a local symmetry lowering caused by weakly correlated rotation of NbO6 octahedra. Based on our findings, we suggest a new stability criterion for mixed-layer structures, which is that net charges of any two consecutive layers do not compensate for each other and only the whole layer sequence is electroneutral. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
London |
Editor |
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| Language |
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Wos |
000365411500036 |
Publication Date |
2015-10-30 |
| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0300-9246; 1477-9226; 1472-7773 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.029 |
Times cited |
5 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:130330 |
Serial |
4256 |
| Permanent link to this record |
| |
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| |
| Author |
Rozova, M.G.; Grigoriev, V.V.; Bobrikov, I.A.; Filimonov, D.S.; Zakharov, K.V.; Volkova, O.S.; Vasiliev, A.N.; Antipov, E.V.; Tsirlin, A.A.; Abakumov, A.M. |
| Title |
Synthesis, structure and magnetic ordering of the mullite-type Bi2Fe4-xCrxO9 solid solutions with a frustrated pentagonal Cairo lattice |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
Dalton T |
| Volume |
45 |
Issue |
45 |
Pages |
1192-1200 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Highly homogeneous mullite-type solid solutions Bi2Fe4-xCrxO9 (x = 0.5, 1, 1.2) were synthesized using a soft chemistry technique followed by a solid-state reaction in Ar. The crystal structure of Bi2Fe3CrO9 was investigated using X-ray and neutron powder diffraction, transmission electron microscopy and Fe-57 Mossbauer spectroscopy (S.G. Pbam, a = 7.95579(9) angstrom , b = 8.39145(9) angstrom, c = 5.98242(7) angstrom, R-F(X-ray) = 0.022, R-F(neutron) = 0.057). The ab planes in the structure are tessellated with distorted pentagonal loops built up by three tetrahedrally coordinated Fe sites and two octahedrally coordinated Fe/Cr sites, linked together in the ab plane by corner-sharing forming a pentagonal Cairo lattice. Magnetic susceptibility measurements and powder neutron diffraction show that the compounds order antiferromagnetically (AFM) with the Neel temperatures decreasing upon increasing the Cr content from T-N similar to 250 K for x = 0 to T-N similar to 155 K for x = 1.2. The magnetic structure of Bi2Fe3CrO9 at T = 30 K is characterized by a propagation vector k = (1/2,1/2,1/2). The tetrahedrally coordinated Fe cations form singlet pairs within dimers of corner-sharing tetrahedra, but spins on the neighboring dimers are nearly orthogonal. The octahedrally coordinated (Fe, Cr) cations form antiferromagnetic up-up-down-down chains along c, while the spin arrangement in the ab plane is nearly orthogonal between nearest neighbors and collinear between second neighbors. The resulting magnetic structure is remarkably different from the one in pure Bi2Fe4O9 and features several types of spin correlations even on crystallographically equivalent exchange that may be caused by the simultaneous presence of Fe and Cr on the octahedral site. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
London |
Editor |
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| Language |
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Wos |
000367614700041 |
Publication Date |
2015-11-30 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0300-9246; 1477-9226; 1472-7773 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.029 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:131095 |
Serial |
4257 |
| Permanent link to this record |
| |
|
| |
| Author |
Cukaric, N.A.; Partoens, B.; Tadic, M.Z.; Arsoski, V.V.; Peeters, F.M. |
| Title |
The 30-band k . p theory of valley splitting in silicon thin layers |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
| Volume |
28 |
Issue |
28 |
Pages |
195303 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The valley splitting of the conduction-band states in a thin silicon-on-insulator layer is investigated using the 30-band k . p theory. The system composed of a few nm thick Si layer embedded within thick SiO2 layers is analyzed. The valley split states are found to cross periodically with increasing quantum well width, and therefore the energy splitting is an oscillatory function of the quantum well width, with period determined by the wave vector K-0 of the conduction band minimum. Because the valley split states are classified by parity, the optical transition between the ground hole state and one of those valley split conduction band states is forbidden. The oscillations in the valley splitting energy decrease with electric field and with smoothing of the composition profile between the well and the barrier by diffusion of oxygen from the SiO2 layers to the Si quantum well. Such a smoothing also leads to a decrease of the interband transition matrix elements. The obtained results are well parametrized by the effective two-valley model, but are found to disagree from previous 30-band calculations. This discrepancy could be traced back to the fact that the basis for the numerical solution of the eigenproblem must be restricted to the first Brillouin zone in order to obtain quantitatively correct results for the valley splitting. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
London |
Editor |
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| Language |
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Wos |
000374394700009 |
Publication Date |
2016-04-19 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
2.649 |
Times cited |
|
Open Access |
|
| Notes |
; This work was supported by the Ministry of Education, Science, and Technological Development of Serbia, the Flemish fund for Scientific Research (FWO-Vl), and the Methusalem programme of the Flemish government. ; |
Approved |
Most recent IF: 2.649 |
| Call Number |
UA @ lucian @ c:irua:133610 |
Serial |
4261 |
| Permanent link to this record |
| |
|
| |
| Author |
Suslu, A.; Wu, K.; Sahin, H.; Chen, B.; Yang, S.; Cai, H.; Aoki, T.; Horzum, S.; Kang, J.; Peeters, F.M.; Tongay, S.; |
| Title |
Unusual dimensionality effects and surface charge density in 2D Mg(OH)2 |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
| Volume |
6 |
Issue |
6 |
Pages |
20525 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
We present two-dimensional Mg(OH)(2) sheets and their vertical heterojunctions with CVD-MoS2 for the first time as flexible 2D insulators with anomalous lattice vibration and chemical and physical properties. New hydrothermal crystal growth technique enabled isolation of environmentally stable monolayer Mg(OH)(2) sheets. Raman spectroscopy and vibrational calculations reveal that the lattice vibrations of Mg(OH)(2) have fundamentally different signature peaks and dimensionality effects compared to other 2D material systems known to date. Sub-wavelength electron energy-loss spectroscopy measurements and theoretical calculations show that Mg(OH)(2) is a 6 eV direct-gap insulator in 2D, and its optical band gap displays strong band renormalization effects from monolayer to bulk, marking the first experimental confirmation of confinement effects in 2D insulators. Interestingly, 2D-Mg(OH)(2) sheets possess rather strong surface polarization (charge) effects which is in contrast to electrically neutral h-BN materials. Using 2D-Mg(OH)(2) sheets together with CVD-MoS2 in the vertical stacking shows that a strong change transfer occurs from n-doped CVD-MoS2 sheets to Mg(OH)(2), naturally depleting the semiconductor, pushing towards intrinsic doping limit and enhancing overall optical performance of 2D semiconductors. Results not only establish unusual confinement effects in 2D-Mg(OH)(2), but also offer novel 2D-insulating material with unique physical, vibrational, and chemical properties for potential applications in flexible optoelectronics. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
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| Language |
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Wos |
000369510300001 |
Publication Date |
2016-02-05 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.259 |
Times cited |
39 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus-short Marie Curie Fellowship. We acknowledge the use of John M. Cowley Center for High Resolution Electron Microscopy at Arizona State University. ; |
Approved |
Most recent IF: 4.259 |
| Call Number |
UA @ lucian @ c:irua:131615 |
Serial |
4272 |
| Permanent link to this record |
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| |
| Author |
Tang, Y.; Hunter, E.C.; Battle, P.D.; Sena, R.P.; Hadermann, J.; Avdeev, M.; Cadogan, J.M. |
| Title |
Structural chemistry and magnetic properties of the perovskite Sr3Fe2TeO9 |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| Volume |
242 |
Issue |
242 |
Pages |
86-95 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
A polycrystalline sample of perovskite-like Sr3Fe2TeO9 has been prepared in a solid-state reaction and studied by a combination of electron microscopy, Mossbauer spectroscopy, magnetometry, X-ray diffraction and neutron diffraction. The majority of the reaction product is shown to be a trigonal phase with a 2:1 ordered arrangement of Fe3+ and Te6+ cations. However, the sample is prone to nano twinning and tetragonal domains with a different pattern of cation ordering exist within many crystallites. Antiferromagnetic ordering exists in the trigonal phase at 300 K and Sr3Fe2TeO9 is thus the first example of a perovskite with 2:1 trigonal cation ordering to show long-range magnetic order. At 300 K the antiferromagnetic phase coexists with two paramagnetic phases which show spin -glass behaviour below similar to 80 K. (C) 2016 The Authors. Published by Elsevier Inc. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000382429600012 |
Publication Date |
2016-06-29 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0022-4596 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.299 |
Times cited |
12 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.299 |
| Call Number |
UA @ lucian @ c:irua:135682 |
Serial |
4310 |
| Permanent link to this record |
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| |
| Author |
Sena, R.P.; Hadermann, J.; Chin, C.-M.; Hunter, E.C.; Battle, P.D. |
| Title |
Structural chemistry and magnetic properties of the perovskite SrLa2Ni2TeO9 |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| Volume |
243 |
Issue |
243 |
Pages |
304-311 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
A polycrystalline sample of SrLa2Ni2TeO9 has been synthesized using a standard ceramic method and characterized by neutron diffraction, magnetometry and electron microscopy. The compound adopts a monoclinic, perovskite-like structure with space group P2(1)/n in and unit cell parameters a=5.6008(1), b = 5.5872(1), c=7.9018(2) angstrom, p=90.021(6)degrees at room temperature. The two crystallographically-distinct B sites are occupied by Ni2+ and Te6+ in ratios of 83:17 and 50:50. Both ac and dc magnetometry suggest that the compound is a spin glass below 35 K but the neutron diffraction data show that some regions of the sample are antiferromagnetic. Electron microscopy revealed twinning on a nanoscale and local variations in composition. These defects are thought to be responsible for the presence of two distinct types of antiferromagnetic ordering. (C) 2016 The Authors. Published by Elsevier Inc. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
London |
Editor |
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| Language |
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Wos |
000384874100041 |
Publication Date |
2016-09-09 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0022-4596 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.299 |
Times cited |
6 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.299 |
| Call Number |
UA @ lucian @ c:irua:137232 |
Serial |
4403 |
| Permanent link to this record |
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| |
| Author |
Milovanovic, S.P.; Peeters, F.M. |
| Title |
Strained graphene Hall bar |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
| Volume |
29 |
Issue |
29 |
Pages |
075601 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The effects of strain, induced by a Gaussian bump, on the magnetic field dependent transport properties of a graphene Hall bar are investigated. The numerical simulations are performed using both classical and quantum mechanical transport theory and we found that both approaches exhibit similar characteristic features. The effects of the Gaussian bump are manifested by a decrease of the bend resistance, RB, around zero-magnetic field and the occurrence of side-peaks in RB. These features are explained as a consequence of bump-assisted scattering of electrons towards different terminals of the Hall bar. Using these features we are able to give an estimate of the size of the bump. Additional oscillations in RB are found in the quantum description that are due to the population/depopulation of Landau levels. The bump has a minor influence on the Hall resistance even for very high values of the pseudo-magnetic field. When the bump is placed outside the center of the Hall bar valley polarized electrons can be collected in the leads. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
London |
Editor |
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| Language |
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Wos |
000391584900001 |
Publication Date |
2016-12-24 |
| Series Editor |
|
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 |
2.649 |
Times cited |
12 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN. ; |
Approved |
Most recent IF: 2.649 |
| Call Number |
UA @ lucian @ c:irua:140381 |
Serial |
4464 |
| Permanent link to this record |
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| |
| Author |
Bogaerts, A.; Khosravian, N.; Van der Paal, J.; Verlackt, C.C.W.; Yusupov, M.; Kamaraj, B.; Neyts, E.C. |
| Title |
Multi-level molecular modelling for plasma medicine |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Journal Of Physics D-Applied Physics |
Abbreviated Journal |
J Phys D Appl Phys |
| Volume |
49 |
Issue |
5 |
Pages |
054002-54019 |
| Keywords |
A1 Journal article; Plasma, laser ablation and surface modeling – Antwerp (PLASMANT) |
| Abstract |
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| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
London |
Editor |
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| Language |
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Wos |
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Publication Date |
0000-00-00 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
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| ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record |
| Impact Factor |
2.588 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.588 |
| Call Number |
UA @ lucian @ c:irua:129798 |
Serial |
4467 |
| Permanent link to this record |
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| |
| Author |
Peelaers, H.; Durgun, E.; Partoens, B.; Bilc, D.I.; Ghosez, P.; Van de Walle, C.G.; Peeters, F.M. |
| Title |
Ab initio study of hydrogenic effective mass impurities in Si nanowires |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
| Volume |
29 |
Issue |
29 |
Pages |
095303 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The effect of B and P dopants on the band structure of Si nanowires is studied using electronic structure calculations based on density functional theory. At low concentrations a dispersionless band is formed, clearly distinguishable from the valence and conduction bands. Although this band is evidently induced by the dopant impurity, it turns out to have purely Si character. These results can be rigorously analyzed in the framework of effective mass theory. In the process we resolve some common misconceptions about the physics of hydrogenic shallow impurities, which can be more clearly elucidated in the case of nanowires than would be possible for bulk Si. We also show the importance of correctly describing the effect of dielectric confinement, which is not included in traditional electronic structure calculations, by comparing the obtained results with those of G(0)W(0) 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 |
London |
Editor |
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| Language |
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Wos |
000395103900002 |
Publication Date |
2017-01-06 |
| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
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Edition |
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| ISSN |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.649 |
Times cited |
1 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the NSF MRSEC Program under award No. DMR11-21053, and the Army Research Office (W911NF-13-1-0380). DIB acknowledges financial support from the grant of the Romanian National Authority for Scientific Research, CNCS UEFISCDI, project No. PN-II-RU-TE-2011-3-0085. Ph G acknowledges a research professorship of the Francqui foundation and financial support of the ARC project AIMED and FNRS project HiT4FiT. This research used resources of the Ceci HPC Center funded by F R S-FNRS (Grant No. 2.5020.1) and of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the US Department of Energy under Contract No. DE-AC02-05CH11231. ; |
Approved |
Most recent IF: 2.649 |
| Call Number |
UA @ lucian @ c:irua:142447 |
Serial |
4584 |
| Permanent link to this record |
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| |
| Author |
Mikhailova, D.; Kuratieva, N.N.; Utsumi, Y.; Tsirlin, A.A.; Abakumov, A.M.; Schmidt, M.; Oswald, S.; Fuess, H.; Ehrenberg, H. |
| Title |
Composition-dependent charge transfer and phase separation in the V1-xRexO2 solid solution |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Journal of the Chemical Society : Dalton transactions |
Abbreviated Journal |
|
| Volume |
46 |
Issue |
5 |
Pages |
1606-1617 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The substitution of vanadium in vanadium dioxide VO2 influences the critical temperatures of structural and metal-to-insulator transitions in different ways depending on the valence of the dopant. Rhenium adopts valence states between + 4 and + 7 in an octahedral oxygen surrounding and is particularly interesting in this context. Structural investigation of V1-xRexO2 solid solutions (0.01 <= x <= 0.30) between 80 and 1200 K using synchrotron X-ray powder diffraction revealed only two polymorphs that resemble VO2: the low-temperature monoclinic MoO2-type form (space group P2(1)/c), and the tetragonal rutile-like form (space group P4(2)/mnm). However, for compositions with 0.03 < x <= 0.15 a phase separation in the solid solution was observed below 1000 K upon cooling down from 1200 K, giving rise to two isostructural phases with slightly different lattice parameters. This is reflected in the appearance of two metal-toinsulator transition temperatures detected by magnetization and specific heat measurements. Comprehensive X-ray photoelectron spectroscopy studies showed that an increased amount of Re leads to a change in the Re valence state from solely Re6+ at a low doping level (<= 3 at% Re) via mixed-valence states Re4+/Re6+ for at least 0.03 < x <= 0.10, up to nearly pure Re4+ in V0.70Re0.30O2. Thus, compositions V1-xRexO2 with only one valence state of Re in the material (Re6+ or Re4+) can be obtained as a single phase, while intermediate compositions are subjected to a phase separation, presumably due to different valence states of Re. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
London |
Editor |
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| Language |
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Wos |
000395442700030 |
Publication Date |
2016-12-24 |
| 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 |
0300-9246; 1477-9226; 1472-7773 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.029 |
Times cited |
1 |
Open Access |
Not_Open_Access |
| Notes |
; The authors are indebted to Dr G. Auffermann (Max Planck Institute for Chemical Physics of Solids, Dresden, Germany) for performing the ICP-OES analyses. This research has received a partial funding from the BMBF, project grant number 03SF0477B (DESIREE). AT acknowledges financial support from Federal Ministry for Education and Research under Sofja Kovalevksaya Award of Alexander von Humboldt Foundation. AMA is grateful to the Russian Science Foundation (grant 14-13-00680) for financial support. ; |
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:142580 |
Serial |
4642 |
| Permanent link to this record |
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| |
| Author |
Zebrowski, D.P.; Peeters, F.M.; Szafran, B. |
| Title |
Driven spin transitions in fluorinated single- and bilayer-graphene quantum dots |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Semiconductor science and technology |
Abbreviated Journal |
Semicond Sci Tech |
| Volume |
32 |
Issue |
6 |
Pages |
065016 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Spin transitions driven by a periodically varying electric potential in dilute fluorinated graphene quantum dots are investigated. Flakes of monolayer graphene as well as electrostatic electron traps induced in bilayer graphene are considered. The stationary states obtained within the tight-binding approach are used as the basis for description of the system dynamics. The dilute fluorination of the top layer lifts the valley degeneracy of the confined states and attenuates the orbital magnetic dipole moments due to current circulation within the flake. The spin-orbit coupling introduced by the surface deformation of the top layer induced by the adatoms allows the spin flips to be driven by the AC electric field. For the bilayer quantum dots the spin flip times is substantially shorter than the spin relaxation. Dynamical effects including many-photon and multilevel transitions are also discussed. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000402405800007 |
Publication Date |
2017-04-19 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0268-1242 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
2.305 |
Times cited |
|
Open Access |
|
| Notes |
; This work was supported by the National Science Centre according to decision DEC-2013/11/B/ST3/03837 and by the Flemish Science Foundation (FWO-VL). ; |
Approved |
Most recent IF: 2.305 |
| Call Number |
UA @ lucian @ c:irua:144238 |
Serial |
4646 |
| Permanent link to this record |
| |
|
| |
| Author |
Bogaerts, A.; Ameye, L.; Bijlholt, M.; Amuli, K.; Heynickx, D.; Devlieger, R. |
| Title |
INTER-ACT : prevention of pregnancy complications through an e-health driven interpregnancy lifestyle intervention: study protocol of a multicentre randomised controlled trial |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
BMC pregnancy and childbirth |
Abbreviated Journal |
Bmc Pregnancy Childb |
| Volume |
17 |
Issue |
|
Pages |
154 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Centre for Research and Innovation in Care (CRIC) |
| Abstract |
Background Excessive maternal pre-pregnancy and gestational weight gain are related to pregnancy- and birth outcomes. The interpregnancy time window offers a unique opportunity to intervene in order to acquire a healthy lifestyle before the start of a new pregnancy. Methods INTER-ACT is an e-health driven multicentre randomised controlled intervention trial targeting women at high risk of pregnancy- and birth related complications. Eligible women are recruited for the study at day 2 or 3 postpartum. At week 6 postpartum, participants are randomised into the intervention or control arm of the study. The intervention focuses on weight, diet, physical activity and mental well-being, and comprises face-to-face coaching, in which behavioural change techniques are central, and use of a mobile application, which is Bluetooth-connected to a weighing scale and activity tracker. The intervention is rolled out postpartum (4 coaching sessions between week 6 and month 6) and in a new pregnancy (3 coaching sessions, one in each trimester of pregnancy); the mobile app is used throughout the two intervention phases. Data collection includes data from the medical record of the participants (pregnancy outcomes and medical history), anthropometric data (height, weight, waist- and hip circumferences, skinfold thickness and body composition by bio-electrical impedance analysis), data from the mobile app (physical activity and weight; intervention group only) and questionnaires (socio-demographics, breastfeeding, food intake, physical activity, lifestyle, psychosocial factors and process evaluation). Medical record data are collected at inclusion and at delivery of the subsequent pregnancy. All other data are collected at week 6 and month 6 postpartum and every subsequent 6 months until a new pregnancy, and in every trimester in the new pregnancy. Primary outcome is the composite endpoint score of pregnancy-induced hypertension, gestational diabetes mellitus, caesarean section, and large-for-gestational-age infant in the subsequent pregnancy. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000402116300002 |
Publication Date |
2017-05-26 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1471-2393 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.263 |
Times cited |
4 |
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 2.263 |
| Call Number |
UA @ lucian @ c:irua:143234 |
Serial |
4663 |
| Permanent link to this record |
| |
|
| |
| Author |
Chin, C.-M.; Sena, R.P.; Hunter, E.C.; Hadermann, J.; Battle, P.D. |
| Title |
Interplay of structural chemistry and magnetism in perovskites : a study of CaLn2Ni2WO9: Ln=La, Pr, Nd |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| Volume |
251 |
Issue |
|
Pages |
224-232 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Polycrystalline samples of CaLn(2)Ni(2)WO(9) (Ln=La, Pr, Nd) have been synthesized and characterised by a combination of X-ray and neutron diffraction, electron microscopy and magnetometry. Each composition adopts a perovskite-like structure with a similar to 5.50, b similar to 5.56, c similar to 7.78 angstrom beta similar to 90.1 degrees in space group P2(1)/n. Of the two crystallographically distinct six-coordinate sites, one is occupied entirely (Ln=Pr) or predominantly (Ln=La, Nd) by Ni2+ and the other by Ni2+ and W6+ in a ratio of approximately 1:2. None of the compounds shows long-range magnetic order at 5 K. The magnetometry data show that the magnetic moments of the Ni2+ cations form a spin glass below 30 K in each case. The Pr3+ moments in CaPr2Ni2WO9 also freeze but the Nd3+ moments in CaNd2Ni2WO9 do not. This behaviour is contrasted with that observed in other (A,A')B2B'O-9 perovskites. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000402581200030 |
Publication Date |
2017-04-22 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0022-4596 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.299 |
Times cited |
5 |
Open Access |
OpenAccess |
| Notes |
; We thank EPSRC for funding through grant EP/M0189541. CMC thanks the Croucher Foundation and Oxford University for a graduate scholarship. We are grateful to Ivan da Silva who provided experimental assistance at ISIS and to Maria Batuk for help with the STEM-EDX analysis. ; |
Approved |
Most recent IF: 2.299 |
| Call Number |
UA @ lucian @ c:irua:144179 |
Serial |
4664 |
| Permanent link to this record |
| |
|
| |
| Author |
Jelić, Z.L.; Milošević, M.V.; Silhanek, A.V. |
| Title |
Velocimetry of superconducting vortices based on stroboscopic resonances |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
| Volume |
6 |
Issue |
|
Pages |
35687 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
An experimental determination of the mean vortex velocity in superconductors mostly relies on the measurement of flux-flow resistance with magnetic field, temperature, or driving current. In the present work we introduce a method combining conventional transport measurements and a frequency-tuned flashing pinning potential to obtain reliable estimates of the vortex velocity. The proposed device is characterized using the time-dependent Ginzburg-Landau formalism, where the velocimetry method exploits the resonances in mean vortex dissipation when temporal commensuration occurs between the vortex crossings and the flashing potential. We discuss the sensitivity of the proposed technique on applied current, temperature and heat diffusion, as well as the vortex core deformations during fast motion. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000385919600001 |
Publication Date |
2016-10-24 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.259 |
Times cited |
22 |
Open Access |
|
| Notes |
; This work was supported by the Research Foundation-Flanders (FWO) and EU COST action MP1201. The work of Z.L.J. and A.V.S. was partially supported by “Mandat d'Impulsion Scientifique” MIS F.4527.13 of the F.R.S.-FNRS. ; |
Approved |
Most recent IF: 4.259 |
| Call Number |
UA @ lucian @ c:irua:144636 |
Serial |
4701 |
| Permanent link to this record |
| |
|
| |
| Author |
Denneulin, T.; Rouvière, J.L.; Béché, A.; Py, M.; Barnes, J.P.; Rochat, N.; Hartmann, J.M.; Cooper, D. |
| Title |
The reduction of the substitutional C content in annealed Si/SiGeC superlattices studied by dark-field electron holography |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Semiconductor science and technology |
Abbreviated Journal |
Semicond Sci Tech |
| Volume |
26 |
Issue |
12 |
Pages |
1-10 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Si/Si(1 − x − y)GexCy superlattices are used in the construction of new microelectronic architectures such as multichannel transistors. The introduction of carbon in SiGe allows for compensation of the strain and to avoid plastic relaxation. However, the formation of incoherent β-SiC clusters during annealing limits the processability of SiGeC. This precipitation leads to a modification of the strain in the alloy due to the reduction of the substitutional carbon content. Here, we investigated the strain in annealed Si/Si0.744Ge0.244C0.012 superlattices grown by reduced pressure chemical vapour deposition using dark-field electron holography. The variation of the substitutional C content was calculated by correlating the results with finite-element simulations. The obtained values were then compared with Fourier-transformed infrared spectrometry measurements. It was shown that after annealing for 2 min at 1050 °C carbon no longer has any influence on strain in the superlattice, which behaves like pure SiGe. However, a significant proportion of substitutional C atoms remain in a third-nearest neighbour (3nn) configuration. It was deduced that the influence of 3nn C on strain is negligible and that only isolated atoms have a significant contribution. It was also proposed that the 3nn configuration is an intermediary step during the formation of SiC clusters. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000300151300010 |
Publication Date |
2011-11-07 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0268-1242 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.305 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.305; 2011 IF: 1.723 |
| Call Number |
UA @ lucian @ c:irua:136427 |
Serial |
4508 |
| Permanent link to this record |
| |
|
| |
| Author |
Ata, I.; Ben Dkhil, S.; Pfannmoeller, M.; Bals, S.; Duche, D.; Simon, J.-J.; Koganezawa, T.; Yoshimoto, N.; Videlot-Ackermann, C.; Margeat, O.; Ackermann, J.; Baeuerle, P. |
| Title |
The influence of branched alkyl side chains in A-D-A oligothiophenes on the photovoltaic performance and morphology of solution-processed bulk-heterojunction solar cells |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Organic chemistry frontiers : an international journal of organic chemistry |
Abbreviated Journal |
Org Chem Front |
| Volume |
4 |
Issue |
4 |
Pages |
1561-1573 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Besides providing sufficient solubility, branched alkyl chains also affect the film-forming and packing properties of organic semiconductors. In order to avoid steric hindrance as it is present in wide-spread alkyl chains comprising a branching point position at the C2-position, i.e., 2-ethylhexyl, the branching point can be moved away from the pi-conjugated backbone. In this report, we study the influence of the modification of the branching point position from the C2-position in 2-hexyldecylamine (1) to the C4-position in 4-hexyldecylamine (2) connected to the central dithieno[3,2-b: 2', 3'-d] pyrrole (DTP) moiety in a well-studied A-D-A oligothiophene on the optoelectronic properties and photovoltaic performance in solution- processed bulk heterojunction solar cells (BHJSCs) with [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as the acceptor material. Post-treatment of the photoactive layers is performed via solvent vapor annealing (SVA) in order to improve the film microstructure of the bulk heterojunction. The time evolution of nanoscale morphological changes is followed by combining scanning transmission electron microscopy with low-energy-loss spectroscopic imaging (STEM-SI), solid-state absorption spectroscopy, and two-dimensional grazing incidence X-ray diffraction (2D-GIXRD). Our results show an improvement of the photovoltaic performance that is dependent on the branching point position in the donor oligomer. Optical spacers are utilized to increase light absorption inside the co-oligomer 2-based BHJSCs leading to increased power conversion efficiencies (PCEs) of 8.2% when compared to the corresponding co-oligomer 1-based devices. A STEM-SI analysis of the respective device cross-sections of active layers containing 1 and 2 as donor materials indeed reveals significant differences in their respective active layer morphologies. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
RSC Publishing |
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000406374800013 |
Publication Date |
2017-05-02 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2052-4129 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.955 |
Times cited |
24 |
Open Access |
OpenAccess |
| Notes |
; We acknowledge financial support by the European Commission under the project “SUNFLOWER” (FP7-ICT-2011-7, grant number: 287594) and S.B. acknowledges the ERC Starting Grant Colouratoms (335078). ; |
Approved |
Most recent IF: 4.955 |
| Call Number |
UA @ lucian @ c:irua:145176UA @ admin @ c:irua:145176 |
Serial |
4727 |
| Permanent link to this record |
| |
|
| |
| Author |
Zarenia, M.; Neilson, D.; Peeters, F.M. |
| Title |
Inhomogeneous phases in coupled electron-hole bilayer graphene sheets : charge density waves and coupled wigner crystals |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
| Volume |
7 |
Issue |
|
Pages |
11510 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
Recently proposed accurate correlation energies are used to determine the phase diagram of strongly coupled electron-hole graphene bilayers. The control parameters of the phase diagram are the charge carrier density and the insulating barrier thickness separating the bilayers. In addition to the electron-hole superfluid phase we find two new inhomogeneous ground states, a one dimensional charge density wave phase and a coupled electron-hole Wigner crystal. The elementary crystal structure of bilayer graphene plays no role in generating these new quantum phases, which are completely determined by the electrons and holes interacting through the Coulomb interaction. The experimental parameters for the new phases lie within attainable ranges and therefore coupled electron-hole bilayer graphene presents itself as an experimental system where novel emergent many-body phases can be realized. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000410739000008 |
Publication Date |
2017-09-11 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.259 |
Times cited |
13 |
Open Access |
|
| Notes |
; We thank Alex Hamilton, Bart Partoens, and Andrea Perali for useful discussions. This work was partially supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program of the Flemish government. D.N. acknowledges support by the University of Camerino FAR project CESEMN. ; |
Approved |
Most recent IF: 4.259 |
| Call Number |
UA @ lucian @ c:irua:145620 |
Serial |
4742 |
| Permanent link to this record |
| |
|
| |
| Author |
Tang, Y.; Sena, R.P.; Aydeev, M.; Battle, P.D.; Cadogan, J.M.; Hadermann, J.; Hunter, E.C. |
| Title |
Magnetic properties of the 6H perovskite Ba3Fe2TeO9 |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
| Volume |
253 |
Issue |
|
Pages |
347-354 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
A polycrystalline sample of Ba3Fe2TeO9 having the 6H perovskite structure has been prepared in a solid-state reaction and studied by a combination of electron microscopy, Mossbauer spectroscopy, magnetometry, X-ray diffraction and neutron diffraction. Partial ordering of Fe3+ and Te6+ cations occurs over the six-coordinate sites; the corner-sharing octahedra are predominantly occupied by the former and the face-sharing octahedra by a 1:1 mixture of the two. On cooling through the temperature range 18 < T/K < 295 an increasing number of spins join an antiferromagnetic backbone running through the structure while the remainder show complex relaxation effects. At 3 K an antiferromagnetic phase and a spin glass coexist. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000406572600047 |
Publication Date |
2017-06-22 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0022-4596 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.299 |
Times cited |
6 |
Open Access |
OpenAccess |
| Notes |
; We thank EPSRC for financial support through grant EP/M018954/1. ; |
Approved |
Most recent IF: 2.299 |
| Call Number |
UA @ lucian @ c:irua:145692 |
Serial |
4743 |
| Permanent link to this record |
