Records |
Author |
Hai, G.-Q.; Candido, L.; Brito, B.G.A.; Peeters, F.M. |
Title |
Electron pairing: from metastable electron pair to bipolaron |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Journal of physics communications |
Abbreviated Journal |
|
Volume |
2 |
Issue |
3 |
Pages |
Unsp 035017 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Starting from the shell structure in atoms and the significant correlation within electron pairs, we distinguish the exchange-correlation effects between two electrons of opposite spins occupying the same orbital from the average correlation among many electrons in a crystal. In the periodic potential of the crystal with lattice constant larger than the effective Bohr radius of the valence electrons, these correlated electron pairs can form a metastable energy band above the corresponding single-electron band separated by an energy gap. In order to determine if these metastable electron pairs can be stabilized, we calculate the many-electron exchange-correlation renormalization and the polaron correction to the two-band system with single electrons and electron pairs. We find that the electron-phonon interaction is essential to counterbalance the Coulomb repulsion and to stabilize the electron pairs. The interplay of the electron-electron and electron-phonon interactions, manifested in the exchange-correlation energies, polaron effects, and screening, is responsible for the formation of electron pairs (bipolarons) that are located on the Fermi surface of the single-electron band. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000434996900022 |
Publication Date |
2018-02-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2399-6528 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
9 |
Open Access |
|
Notes |
; This work was supported by the Brazilian agencies FAPESP and CNPq. GQH would like to thank Prof. Bangfen Zhu for his invaluable support and expert advice. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:152079UA @ admin @ c:irua:152079 |
Serial |
5022 |
Permanent link to this record |
|
|
|
Author |
Nicholas, R.J.; Sasaki, S.; Miura, N.; Peeters, F.M.; Shi, J.M.; Hai, G.Q.; Devreese, J.T.; Lawless, M.J.; Ashenford, D.E.; Lunn, B. |
Title |
Interband magnetooptical studies of resonant polaron coupling in CdTe/Cd1-xMnxTe quantum-wells |
Type |
A1 Journal article |
Year |
1994 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
Volume |
50 |
Issue |
11 |
Pages |
7596-7601 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
Abstract |
Magnetoreflectivity measurements of the 1s and 2s exciton energies in a CdTe/Cd1-xMnxTe superlattice have been made in magnetic fields up to 45 T, showing the resonant polaron coupling of electrons to LO phonons. Strong reflectivity features are seen for both the 1s and 2s excitons, which show a strong field-dependent spin splitting due to the dilute magnetic barriers. At B-z=0, the 2s exciton feature is observed lying 18 meV above the Is state, and is shifted upward in energy by the magnetic fields. No resonant behavior occurs when the 2s state passes through the LO-phonon energy of 21 meV, but at higher fields of around 20 T, the resonances for both spin states (sigma(+/-)) of the 2s exciton broaden and show a strong anticrossing behavior. These experiments are shown to be in excellent agreement with a theoretical treatment which includes the resonant polaron coupling of the electrons alone. Both experiment and theory demonstrate an extremely strong resonant splitting of the 2s exciton states of approximately 11 meV, which is over 50% of the LO-phonon energy. The dominance of single-particle polaron coupling is attributed to the relative sizes of the polaron (35 Angstrom A) and the exciton (50 Angstrom A) radius. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
A1994PJ43700045 |
Publication Date |
2002-07-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.736 |
Times cited |
10 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:99837 |
Serial |
1687 |
Permanent link to this record |
|
|
|
Author |
Brito, B.G.A.; Hai, G.-Q.; Teixeira Rabelo, J.N.; Cândido, L. |
Title |
A quantum Monte Carlo study on electron correlation in all-metal aromatic clusters MAl4 – (M = Li, Na, K, Rb, Cu, Ag and Au) |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
Volume |
16 |
Issue |
18 |
Pages |
8639-8645 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using fixed-node diffusion quantum Monte Carlo (FN-DMC) simulation we investigate the electron correlation in all-metal aromatic clusters MAl4- (with M = Li, Na, K, Rb, Cu, Ag and Au). The electron detachment energies and electron affinities of the clusters are obtained. The vertical electron detachment energies obtained from the FN-DMC calculations are in very good agreement with the available experimental results. Calculations are also performed within the Hartree-Fock approximation, density-functional theory (DFT), and the couple-cluster (CCSD(T)) method. From the obtained results, we analyse the impact of the electron correlation effects in these bimetallic clusters and find that the correlation of the valence electrons contributes significantly to the detachment energies and electron affinities, varying between 20% and 50% of their total values. Furthermore, we discuss the electron correlation effects on the stability of the clusters as well as the accuracy of the DFT and CCSD(T) calculations in the present systems. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
Language |
|
Wos |
000334602900052 |
Publication Date |
2014-03-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1463-9076;1463-9084; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.123 |
Times cited |
10 |
Open Access |
|
Notes |
; This research was supported by CNPq, FAPESP and FAPEG (Brazil). ; |
Approved |
Most recent IF: 4.123; 2014 IF: 4.493 |
Call Number |
UA @ lucian @ c:irua:117247 |
Serial |
2781 |
Permanent link to this record |
|
|
|
Author |
Antipov, E.V.; Putilin, S.N.; Shpanchenko, R.V.; Alyoshin, V.A.; Rozova, M.G.; Abakumov, A.M.; Mikhailova, D.A.; Balagurov, A.M.; Lebedev, O.; Van Tendeloo, G. |
Title |
Structural features, oxygen and fluorine doping in Cu-based superconductors |
Type |
A1 Journal article |
Year |
1997 |
Publication |
Physica: C : superconductivity
T2 – International Conference on Materials and Mechanisms of, Superconductivity – High Temperature Superconductors V, Feb. 28-Mar. 04, 1997, Beijing, Peoples R. China |
Abbreviated Journal |
Physica C |
Volume |
282 |
Issue |
Part 1 |
Pages |
61-64 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The variation of structures and superconducting properties by changing extra oxygen or fluorine atoms concentration in Hg-based Cu mixed oxides and YBa2Cu3O6+delta was studied. The data obtained by NPD study of Hg-1201 can be considered as an evidence of the conventional oxygen doping mechanism with 2 delta holes per (CuO2) layer. The extra oxygen atom was found to be located in the middle of the Hg mesh only. Different formal charges of oxygen and fluorine inserted into reduced 123 structure results in its distinct variations. The fluorine incorporation into strongly reduced YBa2Cu3O6+delta causes a significant structural rearrangement and the formation of a new compound with a composition close to YBa2Cu3O6F2 (tetragonal alpha = 3.87 Angstrom and c approximate to 13 Angstrom), which structure was deduced from the combined results of X-ray diffraction, electron diffraction and high resolution electron microscopy. Fluorination treatment by XeF2 of nonsuperconducting 123 samples causes an appearance of bulk superconductivity with T-c up to 94K. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
Elsevier Science |
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
A1997XZ90400019 |
Publication Date |
2002-07-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.404 |
Times cited |
10 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.404; 1997 IF: 2.199 |
Call Number |
UA @ lucian @ c:irua:95866 |
Serial |
3237 |
Permanent link to this record |
|
|
|
Author |
Teodorescu, V.S.; Mihailescu, I.N.; Gyorgy, E.; Luches, A.; Martino, M.; Nistor, L.C.; van Landuyt, J.; Hermann, J. |
Title |
The study of a crater forming on the surface of a Ti target submitted to multipulse excimer laser irradiation under low pressure N2 |
Type |
A1 Journal article |
Year |
1996 |
Publication |
Journal of modern optics |
Abbreviated Journal |
J Mod Optic |
Volume |
43 |
Issue |
9 |
Pages |
1773-1784 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A Ti target was submitted to laser ablation in low ambient pressure N-2. Electron microscopy examination of the cross-section of the crater zone forming on the Ti target, and XPS analyses, indicate that there is a small effect on the nitridation processes taking place on and in the vicinity of the target. The studies show a zone influenced by the multipulse laser treatment extending beneath the crater down to a depth of the same order of magnitude as the crater depth (i.e. similar to 10 mu m). In this zone, TiN could be identified as being present only in traces, while the whole zone exhibited a layer structure with differences in morphology and mechanical wear. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
A1996VF31900002 |
Publication Date |
2007-07-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0950-0340;1362-3044; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.008 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved |
PHYSICS, APPLIED 47/145 Q2 # |
Call Number |
UA @ lucian @ c:irua:95238 |
Serial |
3594 |
Permanent link to this record |
|
|
|
Author |
Qurashi, A.; Rather, J.A.; Yamazaki, T.; Sohail, M.; De Wael, K.; Merzougui, B.; Hakeem, A.S. |
Title |
Swift electrochemical detection of paraben an endocrine disruptor by In2O3 nanobricks |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Sensors and actuators : B : chemical |
Abbreviated Journal |
Sensor Actuat B-Chem |
Volume |
221 |
Issue |
|
Pages |
167-171 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Novel indium oxide (In2O3) nanobricks have been prepared by template-less and surfactant-free hydrothermal synthesis method and were characterized by X-ray diffraction (XRD), Raman spectroscopy, photoluminescence (PL) spectroscopy and field emission scanning electronic microscopy (FESEM). The synthesized In2O3 nanobricks were successfully immobilized on the surface of glassy carbon electrode for the detection of Parabens (butylparaben). Owing to the unique structure and intriguing properties of these In2O3 nanobricks, the nanostructured thin-film electrode has shown an obvious electrocatalytic activity for the detection of butylparaben (BP). The detection limit (LOD) was estimated as 3 s/m and the sensitivity (LOQ) was calculated as 10 s/m and were found to be 0.08 μM and 0.26 μA μM−1 cm−2 respectively. This sensor showed high sensitivity compared with the reported electrochemical sensors for the detection of BP. The fabricated sensor was successfully applied for the detection of butyl paraben in real cosmetic samples with good recovery ranging from 96.0 to 100.3%. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000362918100021 |
Publication Date |
2015-06-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0925-4005 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
5.401 |
Times cited |
11 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 5.401; 2015 IF: 4.097 |
Call Number |
UA @ admin @ c:irua:127463 |
Serial |
5859 |
Permanent link to this record |
|
|
|
Author |
Mikhailova, D.; Karakulina, O.M.; Batuk, D.; Hadermann, J.; Abakumov, A.M.; Herklotz, M.; Tsirlin, A.A.; Oswald, S.; Giebeler, L.; Schmidt, M.; Eckert, J.; Knapp, M.; Ehrenberg, H. |
Title |
Layered-to-Tunnel Structure Transformation and Oxygen Redox Chemistry in LiRhO2upon Li Extraction and Insertion |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Inorganic chemistry |
Abbreviated Journal |
Inorg Chem |
Volume |
55 |
Issue |
55 |
Pages |
7079-7089 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Layered Li(M,Li)O2 (where M is a transition metal) ordered rock-salt-type structures are used in advanced metal-ion batteries as one of the best hosts for the reversible intercalation of Li ions. Besides the conventional redox reaction involving oxidation/reduction of the M cation upon Li extraction/insertion, creating oxygen-located holes because of the partial oxygen oxidation increases capacity while maintaining the oxidized oxygen species in the lattice through high covalency of the M–O bonding. Typical degradation mechanism of the Li(M,Li)O2 electrodes involves partially irreversible M cation migration toward the Li positions, resulting in gradual capacity/voltage fade. Here, using LiRhO2 as a model system (isostructural and isoelectronic to LiCoO2), for the first time, we demonstrate an intimate coupling between the oxygen redox and M cation migration. A formation of the oxidized oxygen species upon electrochemical Li extraction coincides with transformation of the layered Li1–xRhO2 structure into the γ-MnO2-type rutile–ramsdellite intergrowth LiyRh3O6 structure with rutile-like [1 × 1] channels along with bigger ramsdellite-like [2 × 1] tunnels through massive and concerted Rh migration toward the empty positions in the Li layers. The oxidized oxygen dimers with the O–O distances as short as 2.26 Å are stabilized in this structure via the local Rh–O configuration reminiscent to that in the μ-peroxo-μ-hydroxo Rh complexes. The LiyRh3O6 structure is remarkably stable upon electrochemical cycling illustrating that proper structural implementation of the oxidized oxygen species can open a pathway toward deliberate employment of the anion redox chemistry in high-capacity/high-voltage positive electrodes for metal-ion batteries. Upon chemical or electrochemical oxidation, layered LiRhO2 shows a unique structural transformation that involves both cation migration and oxidation of oxygen resulting in a stable tunnel-like rutile−ramsdellite intergrowth LiyRh3O6 structure. This structure demonstrates excellent performance with the steady and reversible capacity of ∼200 mAh/g. The stability of LiyRh3O6 is rooted in the accommodation of partially oxidized oxygen species through the formation of short O−O distances that are compatible with the connectivity of RhO6 octahedra. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000380181400035 |
Publication Date |
2016-07-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0020-1669 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.857 |
Times cited |
12 |
Open Access |
|
Notes |
Bundesministerium fur Bildung und Forschung, 03SF0477B ; Fonds Wetenschappelijk Onderzoek, G040116N ; |
Approved |
Most recent IF: 4.857 |
Call Number |
EMAT @ emat @ c:irua:140848 |
Serial |
4424 |
Permanent link to this record |
|
|
|
Author |
Savina, A.A.; Morozov, V.A.; Buzlukov, A.L.; Arapova, I.Y.; Stefanovich, S.Y.; Baklanova, Y.V.; Denisova, T.A.; Medvedeva, N.I.; Bardet, M.; Hadermann, J.; Lazoryak, B.I.; Khaikina, E.G. |
Title |
New solid electrolyte Na9Al(MoO4)6 : structure and Na+ ion conductivity |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
29 |
Issue |
20 |
Pages |
8901-8913 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
<script type='text/javascript'>document.write(unpmarked('Solid electrolytes are important materials with a wide range of technological applications. This work reports the crystal structure and electrical properties of a new solid electrolyte Na9Al(MoO4)(6). The monoclinic Na9Al(MoO4)(6) consists of isolated polyhedral, [Al(MoO4)(6)](9-) clusters composed of a central AlO6 octahedron sharing vertices with six MoO4 tetrahedra to form a three-dimensional framework. The AlO6 octahedron also shares edges with one NalO(6) octahedron and two Na2O(6) octahedra. Na3-Na5 atoms are located in the framework cavities. The structure is related to that of sodium ion conductor II-Na3Fe2(AsO4)(3). High-temperature conductivity measurements revealed that the conductivity (sigma) of Na9Al(MoO4)(6) at 803 K equals 1.63 X 10(-2) S cm(-1). The temperature behavior of the Na-23 and Al-27 nuclear magnetic resonance spectra and the spin-lattice relaxation rates of the Na-23 nuclei indicate the presence of fast Na+ ion diffusion in the studied compound. At T\u003C490 K, diffusion occurs by means of Na+ ion jumps exclusively through the sublattice of Na3-Na5 positions, whereas Na1 and Na2 become involved in the diffusion processes (through chemical exchange with the Na3-Na5 sublattice) only at higher temperatures.')); |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Chemical Society |
Place of Publication |
Washington, D.C |
Editor |
|
Language |
|
Wos |
000413884900037 |
Publication Date |
2017-09-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
13 |
Open Access |
OpenAccess |
Notes |
; The research was performed within the state assignment of FASO of Russia (Themes 01201463330, A16-116122810214-9, and 0339-2016-0007), supported in part by the Russian Foundation for Basic Research (Projects 16-03-00510, 16-03-00164, and 17-03-00333). ; |
Approved |
Most recent IF: 9.466 |
Call Number |
UA @ lucian @ c:irua:147432 |
Serial |
4886 |
Permanent link to this record |
|
|
|
Author |
Martens, T.; Mihailova, D.; van Dijk, J.; Bogaerts, A. |
Title |
Theoretical characterization of an atmospheric pressure glow discharge used for analytical spectrometry |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Analytical chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
81 |
Issue |
21 |
Pages |
9096-9108 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We have investigated the plasma processes in an atmospheric pressure glow discharge (APGD) in He used for analytical spectrometry by means of fluid and Monte Carlo (MC) simulations. Typical results include the potential and electric field distributions in the plasma, the density profiles of the various plasma species throughout the discharge, the mean electron energy, as well as the rates of the various collision processes in the plasma, and the relative importance of the different production and loss rates for the various species. The similarities and differences with low-pressure glow discharges are discussed. The main differences are a very small cathode dark space region and a large positive column as well as the dominant role of molecular ions. Some characteristic features of the APGD, such as the occurrence of the different spatial zones in the discharge, are illustrated, with links to experimental observations. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
Language |
|
Wos |
000276191900062 |
Publication Date |
2009-10-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-2700;1520-6882; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.32 |
Times cited |
15 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 6.32; 2009 IF: 5.214 |
Call Number |
UA @ lucian @ c:irua:79554 |
Serial |
3604 |
Permanent link to this record |
|
|
|
Author |
Radaelli, P.G.; Marezio, M.; Tholence, J.L.; de Brion, S.; Santoro, A.; Huang, Q.; Capponi, J.J.; Chaillout, C.; Krekels, T.; Van Tendeloo, G. |
Title |
Crystal structure of the double Hg-layer copper oxide superconductor (Hg, Pr)2Ba2(Y, Ca)Cu2O8-\delta as a function of doping |
Type |
A1 Journal article |
Year |
1995 |
Publication |
The journal of physics and chemistry of solids |
Abbreviated Journal |
J Phys Chem Solids |
Volume |
56 |
Issue |
10 |
Pages |
1471-1478 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
A1995RR95600025 |
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-3697 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.853 |
Times cited |
16 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:13323 |
Serial |
573 |
Permanent link to this record |
|
|
|
Author |
Radaelli, P.G.; Marezio, M.; Tholence, J.L.; Debrion, S.; Santoro, A.; Huang, Q.; Capponi, J.J.; Chaillout, C.; Krekels, T.; Van Tendeloo, G. |
Title |
Crystal-structure of the double-hg-layer copper-oxide superconductor (Hg,Pr)2Ba2(Y,Ca)Cu2O8-\deltaas a function of doping |
Type |
A1 Journal article |
Year |
1995 |
Publication |
The journal of physics and chemistry of solids |
Abbreviated Journal |
J Phys Chem Solids |
Volume |
56 |
Issue |
10 |
Pages |
1471-1478 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The crystal structure of the newly discovered double-Hg-layer copper oxide superconductor (Hg, Pr)(2)Ba-2(Y, Ca)Cu2O8-delta was studied as a function of chemical doping using neutron and electron diffraction and high-resolution transmission electron microscopy (HREM). Rietveld refinements of the structural parameters from neutron powder diffraction data indicate that the oxygen site O3 on the mercury plane is highly defective, being both partially occupied and displaced from the high-symmetry position. The variable concentration of oxygen vacancies partially compensates for the cation doping and, together with the O3 displacement field, makes some of the Hg atoms acquire an unusual pyramidal coordination. HREM images confirm that the structure is of the '2212' type, with very few defects. In some grains, faint superstructure reflections were evidenced by electron diffraction, suggesting that both the oxygen vacancies and the O3 displacement field may order at least on a local scale. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
A1995RR95600025 |
Publication Date |
2002-07-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-3697; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.853 |
Times cited |
16 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:104423 |
Serial |
574 |
Permanent link to this record |
|
|
|
Author |
Shakouri, K.; Vasilopoulos, P.; Vargiamidis, V.; Hai, G.-Q.; Peeters, F.M. |
Title |
Spin- and valley-dependent commensurability oscillations and electric-field-induced quantum Hall plateaux in periodically modulated silicene |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
104 |
Issue |
21 |
Pages |
213109 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study the commensurability oscillations in silicene subject to a perpendicular electric field E-z, a weak magnetic field B, and a weak periodic potential V = V-0 cos(Cy); C = 2 pi/a(0) with a(0) its period. The field E-z and/or the modulation lift the spin degeneracy of the Landau levels and lead to spin and valley resolved Weiss oscillations. The spin resolution is maximal when the field E-z is replaced by a periodic one E-z = E-0 cos(Dy); D = 2 pi/b(0), while the valley one is maximal for b(0) = a(0). In certain ranges of B values, the current is fully spin or valley polarized. Additional quantum Hall conductivity plateaux arise due to spin and valley intra-Landau-level transitions. (C) 2014 AIP Publishing LLC. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000337143000047 |
Publication Date |
2014-05-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-6951;1077-3118; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
16 |
Open Access |
|
Notes |
; The work was supported by the Flemish Science Foundation (FWO-VI), the Methusalem Foundation of the Flemish Government, and by the Canadian NSERC Grant No. OGP0121756. Also, G. Q. H. was supported by FAPESP and CNPq (Brazil). ; |
Approved |
Most recent IF: 3.411; 2014 IF: 3.302 |
Call Number |
UA @ lucian @ c:irua:118409 |
Serial |
3078 |
Permanent link to this record |
|
|
|
Author |
Bekaert, J.; Khestanova, E.; Hopkinson, D.G.; Birkbeck, J.; Clark, N.; Zhu, M.; Bandurin, D.A.; Gorbachev, R.; Fairclough, S.; Zou, Y.; Hamer, M.; Terry, D.J.; Peters, J.J.P.; Sanchez, A.M.; Partoens, B.; Haigh, S.J.; Milošević, M.V.; Grigorieva, I., V |
Title |
Enhanced superconductivity in few-layer TaS₂ due to healing by oxygenation |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Nano Letters |
Abbreviated Journal |
Nano Lett |
Volume |
20 |
Issue |
5 |
Pages |
3808-3818 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
When approaching the atomically thin limit, defects and disorder play an increasingly important role in the properties of two-dimensional (2D) materials. While defects are generally thought to negatively affect superconductivity in 2D materials, here we demonstrate the contrary in the case of oxygenation of ultrathin tantalum disulfide (TaS2). Our first-principles calculations show that incorporation of oxygen into the TaS2 crystal lattice is energetically favorable and effectively heals sulfur vacancies typically present in these crystals, thus restoring the electronic band structure and the carrier density to the intrinsic characteristics of TaS2. Strikingly, this leads to a strong enhancement of the electron-phonon coupling, by up to 80% in the highly oxygenated limit. Using transport measurements on fresh and aged (oxygenated) few-layer TaS2, we found a marked increase of the superconducting critical temperature (T-c) upon aging, in agreement with our theory, while concurrent electron microscopy and electron-energy loss spectroscopy confirmed the presence of sulfur vacancies in freshly prepared TaS2 and incorporation of oxygen into the crystal lattice with time. Our work thus reveals the mechanism by which certain atomic-scale defects can be beneficial to superconductivity and opens a new route to engineer T-c in ultrathin materials. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000535255300114 |
Publication Date |
2020-04-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1530-6984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
10.8 |
Times cited |
16 |
Open Access |
|
Notes |
; This work was supported by Research Foundation-Flanders (FWO). J.Be. acknowledges support of a postdoctoral fellowship of the FWO. The computational resources and services used for the first-principles calculations in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government-department EWI. S.J.H., D.H., and S.F. would like to thank the Engineering and Physical Sciences Research Council (EPSRC) U.K (grants EP/R031711/1, EP/P009050/1 and the Graphene NOWNANO CDT) and the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement ERC-2016-STG-EvoluTEM-715502, the Hetero2D Synergy grant and EC-FET Graphene Flagship) for funding. We thank Diamond Light Source for access and support in use of the electron Physical Science Imaging Centre (Instrument E02 and proposal numbers EM19315 and MG21597) that contributed to the results presented here. ; |
Approved |
Most recent IF: 10.8; 2020 IF: 12.712 |
Call Number |
UA @ admin @ c:irua:170264 |
Serial |
6507 |
Permanent link to this record |
|
|
|
Author |
Su, Y.; Prestat, E.; Hu, C.; Puthiyapura, V.K.; Neek-Amal, M.; Xiao, H.; Huang, K.; Kravets, V.G.; Haigh, S.J.; Hardacre, C.; Peeters, F.M.; Nair, R.R. |
Title |
Self-limiting growth of two-dimensional palladium between graphene oxide layers |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
Volume |
19 |
Issue |
7 |
Pages |
4678-4683 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
The ability of different materials to display self-limiting growth has recently attracted an enormous amount of attention because of the importance of nanoscale materials in applications for catalysis, energy conversion, (opto)-electronics, and so forth. Here, we show that the electrochemical deposition of palladium (Pd) between graphene oxide (GO) sheets result in the self-limiting growth of 5-nm-thick Pd nanosheets. The self-limiting growth is found to be a consequence of the strong interaction of Pd with the confining GO sheets, which results in the bulk growth of Pd being energetically unfavorable for larger thicknesses. Furthermore, we have successfully carried out liquid exfoliation of the resulting Pd-GO laminates to isolate Pd nanosheets and have demonstrated their high efficiency in continuous flow catalysis and electrocatalysis. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000475533900060 |
Publication Date |
2019-06-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1530-6984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.712 |
Times cited |
17 |
Open Access |
|
Notes |
; This work was supported by the Royal Society, Engineering and Physical Sciences Research Council, U.K. (EP/S019367/1, EP/P025021/1, EP/K016946/1, and EP/ P009050/1), Graphene Flagship, and European Research Council (contract 679689 and EvoluTEM). We thank Dr. Sheng Zheng and Dr. K. S. Vasu at the University of Manchester for assisting us with sample preparation and characterization. The authors acknowledge the use of the facilities at the Henry Royce Institute for Advanced Materials and associated support services. V.K.P. and C.H. are grateful for the resources and support provided via membership in the UK Catalysis Hub Consortium and funding by EPSRC (Portfolio grants EP/K014706/2, EP/K014668/1, EP/K014854/1, EP/K014714/1, and EP/I019693/1). F.M.P. and M.N.-A. acknowledge the support from the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 12.712 |
Call Number |
UA @ admin @ c:irua:161245 |
Serial |
5426 |
Permanent link to this record |
|
|
|
Author |
Koelman, P.; Heijkers, S.; Tadayon Mousavi, S.; Graef, W.; Mihailova, D.; Kozak, T.; Bogaerts, A.; van Dijk, J. |
Title |
A Comprehensive Chemical Model for the Splitting of CO2in Non-Equilibrium Plasmas: A Comprehensive Chemical Model for CO2Splitting |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Plasma processes and polymers |
Abbreviated Journal |
Plasma Process Polym |
Volume |
14 |
Issue |
14 |
Pages |
1600155 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
An extensive CO2 plasmamodel is presented that is relevant for the production of ‘‘solar fuels.’’ It is based on reaction rate coefficients fromrigorously reviewed literature, and is augmented with reactionrate coefficients that are obtained fromscaling laws.The input data set,which is suitable for usage with the plasma simulation software Plasimo (https://plasimo.phys.tue.nl/), is available via the Plasimo and publisher’s websites.1 The correctness of this model implementation has been established by independent ZDPlasKin implementation (http://www.zdplaskin.
laplace.univ-tlse.fr/), to verify that the results agree. Results of these ‘‘global models’’ are presented for a DBD plasma reactor. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000403074000009 |
Publication Date |
2016-10-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1612-8850 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.846 |
Times cited |
21 |
Open Access |
Not_Open_Access |
Notes |
Dutch Technology Foundation STW; Ministerie van Economische Zaken; Hercules Foundation; Acknowledgements: This research is supported by the Dutch Technology Foundation STW, which is part of the Netherlands Organization for Scientific Research (NWO), and which is partly funded by the Ministry of Economic Affairs. Furthermore, we acknowledge financial support from the IAP/7 (Inter-university Attraction Pole) program PSI-Physical Chemistry of Plasma- Surface Interactions by the Belgian Federal Office for Science Policy (BELSPO). Part of the calculations were carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UAntwerpen. |
Approved |
Most recent IF: 2.846 |
Call Number |
PLASMANT @ plasmant @ c:irua:142643 |
Serial |
4565 |
Permanent link to this record |
|
|
|
Author |
Zhou, Z.; Tan, Y.; Yang, Q.; Bera, A.; Xiong, Z.; Yagmurcukardes, M.; Kim, M.; Zou, Y.; Wang, G.; Mishchenko, A.; Timokhin, I.; Wang, C.; Wang, H.; Yang, C.; Lu, Y.; Boya, R.; Liao, H.; Haigh, S.; Liu, H.; Peeters, F.M.; Li, Y.; Geim, A.K.; Hu, S. |
Title |
Gas permeation through graphdiyne-based nanoporous membranes |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
13 |
Issue |
1 |
Pages |
4031-4036 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Nanoporous membranes based on two dimensional materials are predicted to provide highly selective gas transport in combination with extreme permeance. Here we investigate membranes made from multilayer graphdiyne, a graphene-like crystal with a larger unit cell. Despite being nearly a hundred of nanometers thick, the membranes allow fast, Knudsen-type permeation of light gases such as helium and hydrogen whereas heavy noble gases like xenon exhibit strongly suppressed flows. Using isotope and cryogenic temperature measurements, the seemingly conflicting characteristics are explained by a high density of straight-through holes (direct porosity of similar to 0.1%), in which heavy atoms are adsorbed on the walls, partially blocking Knudsen flows. Our work offers important insights into intricate transport mechanisms playing a role at nanoscale. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000918423100001 |
Publication Date |
2022-07-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
16.6 |
Times cited |
21 |
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 16.6 |
Call Number |
UA @ admin @ c:irua:194402 |
Serial |
7308 |
Permanent link to this record |
|
|
|
Author |
Kopnin, E.M.; Antipov, E.V.; Capponi, J.J.; Bordet, P.; Chaillout, C.; de Brion, S.; Marezio, M.; Bobylev, A.P.; Van Tendeloo, G. |
Title |
Suppression of superconductivity in Hg-1223 and Hg-1234 by partial replacement of Hg by carbon |
Type |
A1 Journal article |
Year |
1995 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
Volume |
243 |
Issue |
|
Pages |
222-232 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
A1995QL44700004 |
Publication Date |
2003-04-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.942 |
Times cited |
22 |
Open Access |
|
Notes |
|
Approved |
PHYSICS, APPLIED 28/145 Q1 # |
Call Number |
UA @ lucian @ c:irua:13305 |
Serial |
3387 |
Permanent link to this record |
|
|
|
Author |
Brito, B.G.A.; Candido, L.; Hai, G.-Q.; Peeters, F.M. |
Title |
Quantum effects in a free-standing graphene lattice : path-integral against classical Monte Carlo simulations |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
92 |
Issue |
92 |
Pages |
195416 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In order to study quantum effects in a two-dimensional crystal lattice of a free-standing monolayer graphene, we have performed both path-integral Monte Carlo (PIMC) and classical Monte Carlo (MC) simulations for temperatures up to 2000 K. The REBO potential is used for the interatomic interaction. The total energy, interatomic distance, root-mean-square displacement of the atom vibrations, and the free energy of the graphene layer are calculated. The obtained lattice vibrational energy per atom from the classical MC simulation is very close to the energy of a three-dimensional harmonic oscillator 3k(B)T. The PIMC simulation shows that quantum effects due to zero-point vibrations are significant for temperatures T < 1000 K. The quantum contribution to the lattice vibrational energy becomes larger than that of the classical lattice for T < 400 K. The lattice expansion due to the zero-point motion causes an increase of 0.53% in the lattice parameter. A minimum in the lattice parameter appears at T similar or equal to 500 K. Quantum effects on the atomic vibration amplitude of the graphene lattice and its free energy are investigated. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000368095400004 |
Publication Date |
2015-11-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121; 1550-235x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
22 |
Open Access |
|
Notes |
; This research was supported by the Brazilian agencies FAPESP, FAPEG, and CNPq, the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
Call Number |
UA @ lucian @ c:irua:131144 |
Serial |
4232 |
Permanent link to this record |
|
|
|
Author |
da Silva, A.L.C.; Candido, L.; Teixeira Rabelo, J.N.; Hai, G.-Q.; Peeters, F.M. |
Title |
Anharmonic effects on thermodynamic properties of a graphene monolayer |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Europhysics letters |
Abbreviated Journal |
Epl-Europhys Lett |
Volume |
107 |
Issue |
5 |
Pages |
56004 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We extend the unsymmetrized self-consistent-field method (USF) for anharmonic crystals to layered non-Bravais crystals to investigate structural, dynamical and thermodynamic properties of a free-standing graphene monolayer. In this theory, the main anharmonicity of the crystal lattice has been included and the quantum corrections are taken into account in an h-expansion for the one-particle density matrix. The obtained result for the thermal expansion coefficient (TEC) of graphene shows a strong temperature dependence and agrees with experimental results by Bao et al. (Nat. Nanotechnol., 4 (2009) 562). The obtained value of TEC at room temperature (300 K) is -6.4 x 10(- 6) K- 1 and it becomes positive for T > T-alpha = 358K. We find that quantum effects are significant for T < 1000 K. The interatomic distance, effective amplitudes of the graphene lattice vibrations, adiabatic and isothermal bulk moduli, isobaric and isochoric heat capacities are also calculated and their temperature dependences are determined. Copyright (C) EPLA, 2014 |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Paris |
Editor |
|
Language |
|
Wos |
000341559900020 |
Publication Date |
2014-09-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0295-5075;1286-4854; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.957 |
Times cited |
23 |
Open Access |
|
Notes |
; This research was supported by the Brazilian agencies CNPq, FAPEG and FAPESP, the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; |
Approved |
Most recent IF: 1.957; 2014 IF: 2.095 |
Call Number |
UA @ lucian @ c:irua:119289 |
Serial |
118 |
Permanent link to this record |
|
|
|
Author |
Castelano, L.K.; Hai, G.-Q.; Partoens, B.; Peeters, F.M. |
Title |
Artificial molecular quantum rings: spin density functional theory calculations |
Type |
A1 Journal article |
Year |
2006 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
74 |
Issue |
4 |
Pages |
045313,1-5 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000239426800075 |
Publication Date |
2006-07-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
24 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2006 IF: 3.107 |
Call Number |
UA @ lucian @ c:irua:60089 |
Serial |
154 |
Permanent link to this record |
|
|
|
Author |
Hai, G.Q.; Studart, N.; Peeters, F.M. |
Title |
Electron mobility in two coupled δ layers |
Type |
A1 Journal article |
Year |
1995 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
52 |
Issue |
|
Pages |
11273-11276 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
A1995TA85200092 |
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121; 0163-1829 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.736 |
Times cited |
24 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:12193 |
Serial |
980 |
Permanent link to this record |
|
|
|
Author |
Bourgeois, J.; Hervieu, M.; Poienar, M.; Abakumov, A.M.; Elkaïm, E.; Sougrati, M.T.; Porcher, F.; Damay, F.; Rouquette, J.; Van Tendeloo, G.; Maignan, A.; Haines, J.; Martin, C.; |
Title |
Evidence of oxygen-dependent modulation in LuFe2O4 |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
85 |
Issue |
6 |
Pages |
064102-064120,10 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A polycrystalline sample of LuFe2O4 has been investigated by means of powder synchrotron x-ray and neutron diffraction and transmission electron microscopy (TEM), along with Mössbauer spectroscopy and transport and magnetic properties. A monoclinic distortion is unambiguously evidenced, and the crystal structure is refined in the monoclinic C2/m space group [aM = 5.9563(1) Å, bM = 3.4372(1) Å, cM = 8.6431(1) Å, β = 103.24(1)°]. Along with the previously reported modulations distinctive of the charge-ordering (CO) of the iron species, a new type of incommensurate order is observed, characterized by a vector q⃗1 = α1a⃗M* + γ1c⃗M* (with α1 ≅ 0.55, γ1 ≅ 0.13). In situ heating TEM observations from 300 to 773 K confirm that the satellites associated with q⃗1 vanish completely, only at a temperature significantly higher than the CO temperature. This incommensurate modulation has a displacive character and corresponds primarily to a transverse displacive modulation wave of the Lu cations position, as revealed by the high resolution, high angle annular dark field scanning TEM images and in agreement with synchrotron data refinements. Analyses of vacuum-annealed samples converge toward the hypothesis of a new ordering mechanism, associated with a tiny oxygen deviation from the O4 stoichiometry. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000299896900003 |
Publication Date |
2012-02-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
24 |
Open Access |
|
Notes |
Hercules |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
Call Number |
UA @ lucian @ c:irua:95042 |
Serial |
1095 |
Permanent link to this record |
|
|
|
Author |
Hai, G.Q.; Peeters, F.M. |
Title |
Optically detected magnetophonon resonance in polar semiconductors GaAs |
Type |
A1 Journal article |
Year |
1999 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
60 |
Issue |
|
Pages |
16513-16518 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000084791300045 |
Publication Date |
2002-07-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
24 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 1999 IF: NA |
Call Number |
UA @ lucian @ c:irua:27001 |
Serial |
2479 |
Permanent link to this record |
|
|
|
Author |
Hai; Studart; Peeters, F.M. |
Title |
Electron-mobility in 2 coupled delta-layers |
Type |
A1 Journal article |
Year |
1995 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
52 |
Issue |
15 |
Pages |
11273-11276 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The low-temperature transport properties are studied for electrons confined in delta-doped semiconductor structures with two sheets in parallel. The subband quantum mobility and transport mobility are calculated numerically for the Si delta-doped GaAs systems. The effect of coupling of the two delta layers on the electron transport is investigated. Our calculations are in good agreement with experimental results. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
A1995TA85200092 |
Publication Date |
2002-07-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.736 |
Times cited |
25 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:95343 |
Serial |
976 |
Permanent link to this record |
|
|
|
Author |
Castelano, L.K.; Hai, G.-Q.; Partoens, B.; Peeters, F.M. |
Title |
Control of the persistent currents in two interacting quantum rings through the Coulomb interaction and interring tunneling |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
78 |
Issue |
19 |
Pages |
195315,1-195315,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The persistent current in two vertically coupled quantum rings containing few electrons is studied. We find that the Coulomb interaction between the rings in the absence of tunneling affects the persistent current in each ring and the ground-state configurations. Quantum tunneling between the rings alters significantly the ground state and the persistent current in the system. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000262607800074 |
Publication Date |
2008-11-19 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
28 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
Call Number |
UA @ lucian @ c:irua:76020 |
Serial |
500 |
Permanent link to this record |
|
|
|
Author |
Shi, J.M.; Peeters, F.M.; Farias, G.A.; Freire, J.A.K.; Hai, G.Q.; Devreese, J.T.; Bednarek, S.; Adamowski, J. |
Title |
Polaron effect on D- centers in weakly polar semiconductors |
Type |
A1 Journal article |
Year |
1998 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
57 |
Issue |
|
Pages |
3900-3904 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000072163300041 |
Publication Date |
2002-07-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
28 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 1998 IF: NA |
Call Number |
UA @ lucian @ c:irua:21907 |
Serial |
2665 |
Permanent link to this record |
|
|
|
Author |
Wang, F.; Gao, T.; Zhang, Q.; Hu, Z.-Y.; Jin, B.; Li, L.; Zhou, X.; Li, H.; Van Tendeloo, G.; Zhai, T. |
Title |
Liquid-alloy-assisted growth of 2D ternaryGa2In4S9 toward high-performance UV photodetection |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Advanced materials |
Abbreviated Journal |
Adv Mater |
Volume |
31 |
Issue |
2 |
Pages |
1806306 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
2D ternary systems provide another degree of freedom of tuning physical properties through stoichiometry variation. However, the controllable growth of 2D ternary materials remains a huge challenge that hinders their practical applications. Here, for the first time, by using a gallium/indium liquid alloy as the precursor, the synthesis of high-quality 2D ternary Ga2In4S9 flakes of only a few atomic layers thick (approximate to 2.4 nm for the thinnest samples) through chemical vapor deposition is realized. Their UV-light-sensing applications are explored systematically. Photodetectors based on the Ga2In4S9 flakes display outstanding UV detection ability (R-lambda = 111.9 A W-1, external quantum efficiency = 3.85 x 10(4)%, and D* = 2.25 x 10(11) Jones@360 nm) with a fast response speed (tau(ring) approximate to 40 ms and tau(decay) approximate to 50 ms). In addition, Ga2In4S9-based phototransistors exhibit a responsivity of approximate to 10(4) A W-1@360 nm above the critical back-gate bias of approximate to 0 V. The use of the liquid alloy for synthesizing ultrathin 2D Ga2In4S9 nanostructures may offer great opportunities for designing novel 2D optoelectronic materials to achieve optimal device performance. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000455111100013 |
Publication Date |
2018-11-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0935-9648 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
19.791 |
Times cited |
29 |
Open Access |
Not_Open_Access |
Notes |
; F.K.W., T.G, and Q.Z. contributed equally to this work. The authors acknowledge the support from National Nature Science Foundation of China (21825103, 51727809, 51472097, 91622117, and 51872069), National Basic Research Program of China (2015CB932600), and the Fundamental Research Funds for the Central Universities (2017KFKJXX007, 2015ZDTD038, 2017III055, and 2018III039GX). The authors thank the Analytical and Testing Centre of Huazhong University of Science and Technology. ; |
Approved |
Most recent IF: 19.791 |
Call Number |
UA @ admin @ c:irua:156756 |
Serial |
5254 |
Permanent link to this record |
|
|
|
Author |
Van Tendeloo, G.; Chaillout, C.; Capponi, J.J.; Marezio, M.; Antipov, E.V. |
Title |
Atomic structure and defect structure of the superconducting HgBa2Can-1CunO2n+2+\delta homologous series |
Type |
A1 Journal article |
Year |
1994 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
Volume |
223 |
Issue |
3/4 |
Pages |
219-226 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The perfect as well as the defect structure of several members of the superconducting family HgBa2Can-1CunO2n+2+delta have been studied in detail by electron diffraction and high-resolution electron microscopy Identification of the cation configuration is possible, even in the defect regions, with the help of computer simulations. The fine structure of several defects is analyzed in detail, the most common defect being the intergrowth of slabs corresponding to different n values in the title formula. In general, however, the crystals are of a high perfection, particularly for the lower n members. The occurrence of double (HgO)delta layers is seen occasionally, indicating the possible existence of a material with a double mercury layer. Some of these defects are possibly related to recently discovered anomalies at 250 K in these compounds. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
A1994NG47600003 |
Publication Date |
2002-10-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.942 |
Times cited |
30 |
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ lucian @ c:irua:10028 |
Serial |
196 |
Permanent link to this record |
|
|
|
Author |
Hu, S.; Gopinadhan, K.; Rakowski, A.; Neek-Amal, M.; Heine, T.; Grigorieva, I.V.; Haigh, S.J.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M. |
Title |
Transport of hydrogen isotopes through interlayer spacing in van der Waals crystals |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Nature nanotechnology |
Abbreviated Journal |
Nat Nanotechnol |
Volume |
13 |
Issue |
6 |
Pages |
468-+ |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Atoms start behaving as waves rather than classical particles if confined in spaces commensurate with their de Broglie wavelength. At room temperature this length is only about one angstrom even for the lightest atom, hydrogen. This restricts quantum-confinement phenomena for atomic species to the realm of very low temperatures(1-5). Here, we show that van der Waals gaps between atomic planes of layered crystals provide angstrom-size channels that make quantum confinement of protons apparent even at room temperature. Our transport measurements show that thermal protons experience a notably higher barrier than deuterons when entering van der Waals gaps in hexagonal boron nitride and molybdenum disulfide. This is attributed to the difference in the de Broglie wavelengths of the isotopes. Once inside the crystals, transport of both isotopes can be described by classical diffusion, albeit with unexpectedly fast rates comparable to that of protons in water. The demonstrated angstrom-size channels can be exploited for further studies of atomistic quantum confinement and, if the technology can be scaled up, for sieving hydrogen isotopes. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000434715700015 |
Publication Date |
2018-04-04 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1748-3387; 1748-3395 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
38.986 |
Times cited |
32 |
Open Access |
|
Notes |
; The authors acknowledge support from the Lloyd's Register Foundation, EPSRC – EP/N010345/1, the European Research Council ARTIMATTER project – ERC-2012-ADG and from Graphene Flagship. M.L.-H. acknowledges a Leverhulme Early Career Fellowship. ; |
Approved |
Most recent IF: 38.986 |
Call Number |
UA @ lucian @ c:irua:152014UA @ admin @ c:irua:152014 |
Serial |
5046 |
Permanent link to this record |
|
|
|
Author |
Sreepal, V.; Yagmurcukardes, M.; Vasu, K.S.; Kelly, D.J.; Taylor, S.F.R.; Kravets, V.G.; Kudrynskyi, Z.; Kovalyuk, Z.D.; Patane, A.; Grigorenko, A.N.; Haigh, S.J.; Hardacre, C.; Eaves, L.; Sahin, H.; Geim, A.K.; Peeters, F.M.; Nair, R.R. |
Title |
Two-dimensional covalent crystals by chemical conversion of thin van der Waals materials |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
Volume |
19 |
Issue |
9 |
Pages |
6475-6481 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Most of the studied two-dimensional (2D) materials have been obtained by exfoliation of van der Waals crystals. Recently, there has been growing interest in fabricating synthetic 2D crystals which have no layered bulk analogues. These efforts have been focused mainly on the surface growth of molecules in high vacuum. Here, we report an approach to making 2D crystals of covalent solids by chemical conversion of van der Waals layers. As an example, we used 2D indium selenide (InSe) obtained by exfoliation and converted it by direct fluorination into indium fluoride (InF3), which has a nonlayered, rhombohedral structure and therefore cannot possibly be obtained by exfoliation. The conversion of InSe into InF3 is found to be feasible for thicknesses down to three layers of InSe, and the obtained stable InF3 layers are doped with selenium. We study this new 2D material by optical, electron transport, and Raman measurements and show that it is a semiconductor with a direct bandgap of 2.2 eV, exhibiting high optical transparency across the visible and infrared spectral ranges. We also demonstrate the scalability of our approach by chemical conversion of large-area, thin InSe laminates obtained by liquid exfoliation, into InF3 films. The concept of chemical conversion of cleavable thin van der Waals crystals into covalently bonded noncleavable ones opens exciting prospects for synthesizing a wide variety of novel atomically thin covalent crystals. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000486361900083 |
Publication Date |
2019-08-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1530-6984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.712 |
Times cited |
32 |
Open Access |
|
Notes |
; This work was supported by the Royal Society, the European Research Council (contract 679689 and EvoluTEM 715502), and Engineering and Physical Sciences Research Council, U.K. (EP/N013670/1), The authors acknowledge the use of the facilities at the Henry Royce Institute for Advanced Materials and associated support services. H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 117F095. M.Y. acknowledges the Flemish Science Foundation (FWO-Vl) for a postdoctoral fellowship. S.J.H. and D.J.K. acknowledge support from EPSRC (EP/P009050/1) and the NowNANO CDT. ; |
Approved |
Most recent IF: 12.712 |
Call Number |
UA @ admin @ c:irua:162818 |
Serial |
5431 |
Permanent link to this record |