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Records |
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Author |
Blumenau, A.T.; Jones, R.; Frauenheim, T.; Willems, B.; Lebedev, O.I.; Van Tendeloo, G.; Fisher, D.; Martineau, P.M. |
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Title |
Dislocations in diamond : dissociation into partials and their glide motion |
Type |
A1 Journal article |
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Year |
2003 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
68 |
Issue |
1 |
Pages |
014115-14119 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The dissociation of 60degrees and screw dislocations in diamond is modeled in an approach combining isotropic elasticity theory with ab initio-based tight-binding total-energy calculations. Both dislocations are found to dissociate with a substantial lowering of their line energies. For the 60degrees dislocation, however, an energy barrier to dissociation is found. We investigate the core structure of a screw dislocation distinguishing “shuffle,” “mixed,” and “glide” cores. The latter is found to be the most stable undissociated screw dislocation. Further, the glide motion of 90degrees and 30degrees partials is discussed in terms of a process involving the thermal formation and subsequent migration of kinks along the dislocation line. The calculated activation barriers to dislocation motion show that the 30degrees partial is less mobile than the 90degrees partial. Finally, high-resolution electron microscopy is performed on high-temperature, high-pressure annealed natural brown diamond, allowing the core regions of 60degrees dislocations to be imaged. The majority of dislocations are found to be dissociated. However, in some cases, undissociated 60degrees dislocations were also observed. |
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Wos |
000184582900050 |
Publication Date |
2003-08-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0163-1829;1095-3795; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
39 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2003 IF: NA |
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Call Number |
UA @ lucian @ c:irua:103800 |
Serial |
734 |
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Permanent link to this record |
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Author |
Baelus, B.J.; Peeters, F.M. |
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Title |
Multiply connected mesoscopic superconductors |
Type |
A1 Journal article |
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Year |
2003 |
Publication |
Modern physics letters B
T2 – 3rd International Conference on Modern Problems in Superconductivity, SEP 09-14, 2002, YALTA, UKRAINE |
Abbreviated Journal |
Mod Phys Lett B |
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Volume |
17 |
Issue |
10-12 |
Pages |
527-536 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Multiply connected mesoscopic: superconductors are considered within the framework of the nonlinear Ginzburg-Landau theory. The two coupled nonlinear equations are solved numerically and we investigated the properties of a superconducting ring, two concentric rings, and an asymmetric ring. We find that (i) for a mesoscopic superconducting ring the flux through the hole is not quantized, (ii) two concentric mesoscopic superconducting rings are magnetically coupled and the interaction energy increases with increasing sample thickness, and (iii) in asymmetric rings, a stationary phase slip state is predicted. |
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Publisher |
World scientific publ co pte ltd |
Place of Publication |
Singapore |
Editor |
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Language |
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Wos |
000184303900016 |
Publication Date |
2003-07-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0217-9849;1793-6640; |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
0.617 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 0.617; 2003 IF: 0.461 |
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Call Number |
UA @ lucian @ c:irua:103810 |
Serial |
2236 |
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Permanent link to this record |
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Author |
Ivanov, V.A.; Krstajic, P.M.; Peeters, F.M.; Fleurov, V.; Kikoin, K. |
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Title |
On the ferromagnetic exchange in Mn-doped III-V semiconductors |
Type |
A1 Journal article |
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Year |
2003 |
Publication |
Physica: B : condensed matter
T2 – 23rd International Conference on Low Temperature Physics (LT23), AUG 20-27, 2002, HIROSHIMA, JAPAN |
Abbreviated Journal |
Physica B |
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Volume |
329 |
Issue |
Part 2 |
Pages |
1282-1283 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We propose a microscopic model for double exchange in GaAs:Mn, GaP:Mn which is based on the interaction between the transition metal impurities and the heavy holes of host semiconductor. The kinematic exchange is derived and the Curie temperature is calculated which agrees with recent experiments. (C) 2003 Elsevier Science B.V. All rights reserved. |
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Corporate Author |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000183802700400 |
Publication Date |
2003-02-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0921-4526; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.386 |
Times cited |
5 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.386; 2003 IF: 0.908 |
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Call Number |
UA @ lucian @ c:irua:103813 |
Serial |
2435 |
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Permanent link to this record |
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Author |
Anisimovas, E.; Peeters, F.M. |
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Title |
Few-particle states in coupled electron-hole quantum dots |
Type |
P1 Proceeding |
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Year |
2003 |
Publication |
Functions II |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
330-337 |
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Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
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Abstract |
We apply the exact diagonalization technique to calculate the ground and excited states of a bipolar artificial molecule composed of two vertically coupled quantum dots containing different types of carriers electrons and holes in equilibrium. In this system, the magnetic field tunes the relative role of intra-dot Coulomb interaction while the inter-dot separation sets the strength of inter-dot correlations. We find an intricate pattern of the switching of the ground-state angular momentum with increasing magnetic field and a rearrangement of approximate single-particle levels as a function of the inter-dot coupling strength. |
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Wos |
000229502400029 |
Publication Date |
2007-11-07 |
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Series Issue |
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Edition |
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ISSN |
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ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:103838 |
Serial |
1186 |
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Permanent link to this record |
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Author |
Wang, Z.-H.; Kronmüller, H.; Lebedev, O.I.; Gross, G.M.; Razavi, F.S.; Habermeier, H.U.; Shen, B.G. |
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Title |
Phase transition and magnetic anisotropy of (La,Sr)MnO3 thin films |
Type |
A1 Journal article |
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Year |
2002 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
65 |
Issue |
5 |
Pages |
054411-54416 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The magnetic proper-ties and their correlation with the microstructure and electrical transport are investigated in La0.88Sr0.1MnO3 films grown on (100)SrTiO3 Single crystal substrates with thickness ranging from 100 to 2500 Angstrom. The ultrathin film (t = 100 Angstrom) has a single ferromagnetic transition (FMT) at T-c of 250 K, whereas the thicker films exhibit two FMTs, with the main one at a lowered T-c of 200 K while the minor one around 300 K. Furthermore, a thickness dependent magnetic anisotropy has been found, strongly indicating the existence of strain effect, which is also revealed by the transmission electron microscopy study. The suppressed Jahn-Teller distortion (JTD) by the epitaxial strain, and the recovered JTD due to the strain relexation are suggested to explain the metallic behavior in thin films and the insulating behavior in the thick film (t = 2500 Angstrom), repectively. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000173647000058 |
Publication Date |
2002-07-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0163-1829;1095-3795; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
23 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2002 IF: NA |
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Call Number |
UA @ lucian @ c:irua:103883 |
Serial |
2592 |
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Permanent link to this record |
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Author |
Baelus, B.J.; Yampolskii, S.V.; Peeters, F.M.; Montevecchi, E.; Indekeu, J.O. |
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Title |
Superconducting properties of mesoscopic cylinders with enhanced surface superconductivity |
Type |
A1 Journal article |
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Year |
2002 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
65 |
Issue |
2 |
Pages |
024510-10 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The superconducting state of an infinitely long superconducting cylinder surrounded by a medium which enhances its superconductivity near the boundary is studied within the nonlinear Ginzburg-Landau theory. This enhancement can be due to the proximity of another superconductor or due to surface treatment. Quantities such as the free energy, the magnetization and the Cooper-pair density are calculated. Phase diagrams are obtained to investigate how the critical field and the critical temperature depend on this surface enhancement for different values of the Ginzburg-Landau parameter kappa. Increasing the superconductivity near the surface leads to higher critical fields and critical temperatures. For small cylinder diameters only giant vortex states nucleate, while for larger cylinders multivortices can nucleate. The stability of these multivortex states also depends on the surface enhancement. For type-I superconductors we found the remarkable result that for a range of values of the surface extrapolation length the superconductor can transit from the Meissner state into superconducting states with vorticity L > 1. Such a behavior is not found for the case of large kappa, i.e., type-II superconductivity, |
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Place of Publication |
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Language |
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Wos |
000173213100099 |
Publication Date |
2002-07-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0163-1829;1095-3795; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
13 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2002 IF: NA |
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Call Number |
UA @ lucian @ c:irua:103890 |
Serial |
3363 |
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Permanent link to this record |
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Author |
Riva, C.; Peeters, F.M.; Varga, K. |
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Title |
Theory of trions in quantum wells |
Type |
A1 Journal article |
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Year |
2002 |
Publication |
Physica. E: Low-dimensional systems and nanostructures
T2 – 14th International Conference on the Electronic Properties of, Two-Dimensional Systems, JUL 30-AUG 03, 2001, PRAGUE, CZECH REPUBLIC |
Abbreviated Journal |
Physica E |
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Volume |
12 |
Issue |
1-4 |
Pages |
543-545 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
We investigate the energy levels of the negatively and positively charged excitons (also called trions) in a 200 Angstrom wide GaAs quantum well in the presence of a perpendicular magnetic field. A comparison is made with the experimental results of Glasberg et al. (Phys. Rev. B. 59 (1999) R10 425) and of Yusa et al. (cond-mat/0103505). (C) 2002 Elsevier Science B.V. All rights reserved. |
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Publisher |
North-Holland |
Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000175206300134 |
Publication Date |
2002-10-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1386-9477; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.221 |
Times cited |
2 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.221; 2002 IF: 1.107 |
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Call Number |
UA @ lucian @ c:irua:103903 |
Serial |
3624 |
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Permanent link to this record |
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Author |
Schweigert, I.V.; Schweigert, V.A.; Peeters, F.M. |
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Title |
Influence of the lattice symmetry on melting of the bilayer Wigner crystal |
Type |
A1 Journal article |
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Year |
2000 |
Publication |
Journal de physique: 4
T2 – International Conference on Strongly Coupled Coulomb Systems, SEP 04-10, 1999, ST MALO, FRANCE |
Abbreviated Journal |
J Phys Iv |
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Volume |
10 |
Issue |
P5 |
Pages |
117-120 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The melting transition of the five different lattices of a bilayer crystal is studied using the Monte-Carlo (MC) technique. We found the surprising result that the square lattice has a substantial larger melting temperature as compared to the other lattice structures, which is a consequence of the specific topology of the temperature induced defects. A new melting criterion is formulated which we show to be universal for bilayers as well as for single layer crystals. |
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Publisher |
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Place of Publication |
Les Ulis |
Editor |
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Language |
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Wos |
000087026300016 |
Publication Date |
2007-07-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1155-4339; |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:103954 |
Serial |
1647 |
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Permanent link to this record |
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Author |
Buschmann, V.; Rodewald, M.; Fuess, H.; Van Tendeloo, G.; Schäffer, C. |
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Title |
High resolution electron microscopy study of molecular beam epitaxy grown CoSi2/Si1-xGex/Si(100) heterostructurs |
Type |
A1 Journal article |
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Year |
1999 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
85 |
Issue |
4 |
Pages |
2119-2123 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Two CoSi2/Si1-xGex/Si(100) heterostructures, with different Ge content, made by molecular beam epitaxy are characterized by high resolution electron microscopy. In general, the interface between the CoSi2 thin film and the Si1-xGex layer is of a high structural quality and the strained Si1-xGex layer exhibits few defects. For both samples, different interface structures are present, although the dominant interfacial configuration is similar to the unreconstructed interface present at the CoSi2/Si(100) interface. Only occasionally (2x1) reconstructed interface regions are found which are just a few nanometers in length. Phenomena such as Ge segregation and the introduction of defects are also observed in the Si1-xGex layer. We attribute the minimal presence of the reconstructed interface to both the (2x8):Si1-xGex(100) surface reconstruction and the Ge segregation that takes place. (C) 1999 American Institute of Physics. [S0021-8979(99)02104-0]. |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000078403000017 |
Publication Date |
2002-07-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
6 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.068; 1999 IF: 2.275 |
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Call Number |
UA @ lucian @ c:irua:103977 |
Serial |
1455 |
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Permanent link to this record |
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Author |
Shevchenko, V.P.; Lisitzin, A.P.; Kuptzov, V.M.; Van Malderen, H.; Martin, J.M.; Van Grieken, R.; Huang, W.W. |
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Title |
Composition of aerosols in the marine boundary layer over the seas of the western Russian Arctic |
Type |
A1 Journal article |
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Year |
1999 |
Publication |
Omnia therapeutica. supplemento |
Abbreviated Journal |
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Volume |
39 |
Issue |
1 |
Pages |
142-151 |
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Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
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Abstract |
During the SPASIBA expedition (Scientific Program on Arctic and Siberian Aquatorium) on board RV “Yakov Smirnitzky” to the Laptev Sea 10 samples of aerosols in the marine boundary layer have been collected by nylon meshes in August-September 1991. The composition of the samples was studied by a combined approach of different analytical techniques (single-particle analysis, instrumental neutron activation analysis, and atomic absorption spectrometry). The mass concentration of coarse (>1 mu m) insoluble fraction of aerosols was from 0.08 to 0.46 mu g/m(3). In all samples remains of land vegetation were found as the main component. The organic carbon content of the aerosols ranged from 23 to 49%. The inorganic part of the samples is represented mainly by alumosilicates and quartz, In all samples anthropogenic fly ash particles were detected, Temporal variations of the element concentrations are caused by various air masses transported to the study area. |
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Wos |
000079729200019 |
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Series Editor |
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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 |
0030-1574 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ admin @ c:irua:103979 |
Serial |
7706 |
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Permanent link to this record |
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Author |
Dzhurakhalov, A.A.; Atanasov, I.; Hou, M. |
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Title |
Calculation of binary and ternary metallic immiscible clusters with icosahedral structures |
Type |
A1 Journal article |
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Year |
2008 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
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Issue |
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Pages |
115415 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Recently, core-shell Ag-Co, Ag-Cu, and “onionlike” Cu-Co equilibrium configurations were predicted in the case of isolated face centered cubic (fcc) bimetallic clusters, and three shell onionlike configurations were predicted in the case of ternary metallic clusters with spherical and truncated octahedral morphologies. In the present paper, immiscible binary CuCo and ternary AgCuCo clusters with icosahedral structures are studied as functions of their size and composition. Clusters studied are formed by 13, 55, 147, 309, and 561 atoms corresponding to the five smallest possible closed shell icosahedral structures. An embedded atom model potential is used to describe their cohesion. Equilibrium configurations are investigated by means of Metropolis Monte Carlo free energy minimization in the (NPT) canonical ensemble. Most simulations are achieved at 10 and 300 K. The effect of temperature on segregation ordering is systematically investigated. Selected cases are used to identify the effect of size and composition on melting. In contrast with fcc clusters, homogeneous onionlike configurations of binary clusters are not predicted. When it is allowed by the composition, a complete outer shell is formed by Cu in binary Cu-Co clusters and by Ag in ternary Ag-Cu-Co clusters. Depending on temperature, Co may precipitate into decahedral groups under the Cu vertices of the icosahedra in binary clusters, while the Co-Cu configuration in ternary clusters drastically depends on the Ag coating. Despite the multicomponent character of the clusters and the immiscibility of the species forming them, for most compositions and sizes, equilibrium structures remain close to perfectly icosahedral at 10 K as well as at 300 K. |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000254542800167 |
Publication Date |
2008-03-11 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121; 1550-235x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
11 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2008 IF: 3.322 |
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Call Number |
UA @ lucian @ c:irua:104033 |
Serial |
4517 |
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Permanent link to this record |
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Author |
Krsmanovic, R.; Morozov, V.A.; Lebedev, O.I.; Polizzi, S.; Speghini, A.; Bettinelli, M.; Van Tendeloo, G. |
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Title |
Structural and luminescence investigation on gadolinium gallium garnet nanocrystalline powders prepared by solution combustion synthesis |
Type |
A1 Journal article |
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Year |
2007 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
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Volume |
18 |
Issue |
32 |
Pages |
325604-325609 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
|
Abstract |
Nanocrystalline powders of undoped and lanthanide (Pr3+, Tm3+)- doped gadolinium gallium garnet, Gd3Ga5O12 (GGG), were prepared by propellant synthesis and studied by x-ray powder diffraction (XRD), electron diffraction (ED), high-resolution electron microscopy (HREM) and luminescence spectroscopy. The x-ray diffraction patterns of the GGG samples were analysed using the Rietveld method. The Rietveld refinement reveals the existence of two garnet-type phases: both are cubic (space group Ia $(3) over bar $d) with a slightly different lattice parameter and probably a slightly different composition. Electron diffraction and electron microscopy measurements confirm the x-ray diffraction results. EDX measurements for lanthanide-doped samples show that stable solid solutions with composition Gd(3-x)Ln(x)Ga(5)O(12), x approximate to 0.3 ( Ln = Pr; Tm) have been obtained. The luminescence properties of the Tm3+ -doped nanocrystalline GGG samples were measured and analysed. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Bristol |
Editor |
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|
|
Language |
|
Wos |
000248231300010 |
Publication Date |
2007-07-14 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.44 |
Times cited |
33 |
Open Access |
|
|
|
Notes |
Iap5-01 |
Approved |
Most recent IF: 3.44; 2007 IF: 3.310 |
|
|
Call Number |
UA @ lucian @ c:irua:104042 |
Serial |
3195 |
|
Permanent link to this record |
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|
|
|
Author |
Ferreira, W.P.; Peeters, F.M.; Farias, G.A. |
|
|
Title |
Melting and evaporation in classical two-dimensional clusters confined by a Coulomb potential |
Type |
A1 Journal article |
|
Year |
2005 |
Publication |
Physical review : E : statistical, nonlinear, and soft matter physics |
Abbreviated Journal |
Phys Rev E |
|
|
Volume |
72 |
Issue |
4 Part 1 |
Pages |
041502-41507 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
The thermal properties of a two-dimensional classical cluster of negatively charged particles bound by a punctual positive charge are presented. The melting phenomenon is analyzed and the features which characterize such a solid-liquid transition are highlighted. We found that the presence of metastable states strongly modifies the melting scenario, and that the melting temperature of the system is determined by the height of the saddle point energy separating the ground state and the metastable state. Due to the particular type of confinement potential considered in this paper, we also found that, at sufficiently large temperature, the cluster can become thermally ionized. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
Woodbury (NY) |
Editor |
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|
|
Language |
|
Wos |
000232930600030 |
Publication Date |
2005-10-06 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.366 |
Times cited |
4 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.366; 2005 IF: 2.418 |
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|
Call Number |
UA @ lucian @ c:irua:104067 |
Serial |
1983 |
|
Permanent link to this record |
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|
Author |
Krstajic, P.; Peeters, F.M. |
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|
Title |
Spin-dependent tunneling in diluted magnetic semiconductor trilayer structures |
Type |
A1 Journal article |
|
Year |
2005 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
|
Volume |
72 |
Issue |
12 |
Pages |
125350-125356 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
Tunneling of holes through a trilayer structure made of two diluted magnetic semiconductors, (Ga,Mn)As, separated by a thin layer of nonmagnetic AlAs is investigated. The problem is treated within the 6x6 Luttinger-Kohn model for valence bands with the split-off band included. The influence of the spin-orbit coupling is pronounced as the spin-splitting Delta(ex) is comparable with the split-off Delta(SO) splitting. It is assumed that direct tunneling is the dominant mechanism due to the high quality of the tunnel junctions. Our theoretical results predict the correct order of magnitude for the tunneling magnetoresistance ratio, but various other effects, such as scattering on impurities and defects, should be included in order to realize a quantitative agreement with experiment. |
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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 |
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Editor |
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Language |
|
Wos |
000232229400116 |
Publication Date |
2005-09-30 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
8 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.836; 2005 IF: 3.185 |
|
|
Call Number |
UA @ lucian @ c:irua:104068 |
Serial |
3086 |
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Permanent link to this record |
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Author |
Vasilopoulos, P.; Wang, X.F.; Peeters, F.M.; Chowdhury, S.; Long, A.R.; Davies, J.H. |
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Title |
Magneto resistance oscillations in a modulated 2DEG periodic in the ratio h/e to flux per unit cell |
Type |
A1 Journal article |
|
Year |
2004 |
Publication |
Physica. E: Low-dimensional systems and nanostructures
T2 – 15th International Conference on Electronic Properties of, Two-Dimensional Systems (EP2DS-15), JUL 14-18, 2003, Nara, JAPAN |
Abbreviated Journal |
Physica E |
|
|
Volume |
22 |
Issue |
1-3 |
Pages |
389-393 |
|
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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|
Abstract |
Transport properties of the 2DEG are studied in the presence of a normal magnetic field B and of a weak, two-dimensional periodic potential modulation. A tight-binding treatment has shown that each Landau level splits into several subbands with exponentially small gaps between them. Assuming the latter are closed due to disorder gives analytical wave functions and simplifies the evaluation of the magnetoresistance tensor p(muv) The relative phase of the oscillations in p(xx) and p(yy) depends on the modulation strengths and periods. For short periods less than or equal to 100 nm, in addition to the Weiss oscillations, the collisional contribution to the conductivity and the corresponding resistivity contribution show prominent peaks when one flux quantum h/e passes through an integral number of unit cells in good agreement with experiments. For periods 300-400 nm long used in early experiments, these peaks occur at fields 10-25 times smaller than those of the Weiss oscillations and are not resolved. (C) 2003 Elsevier B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
North-Holland |
Place of Publication |
Amsterdam |
Editor |
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Language |
|
Wos |
000221140800094 |
Publication Date |
2004-02-10 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1386-9477; |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
|
Impact Factor |
2.221 |
Times cited |
|
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.221; 2004 IF: 0.898 |
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|
Call Number |
UA @ lucian @ c:irua:104107 |
Serial |
1911 |
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Permanent link to this record |
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Author |
Ferreira, W.P.; Matulis, A.; Farias, G.A.; Peeters, F.M. |
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|
Title |
Structure and correlations in two-dimensional classical artificial atoms confined by a Coulomb potential |
Type |
A1 Journal article |
|
Year |
2003 |
Publication |
Physical review : E : statistical, nonlinear, and soft matter physics |
Abbreviated Journal |
Phys Rev E |
|
|
Volume |
67 |
Issue |
4Part 2 |
Pages |
046601-46608 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The ordering of N equally charged particles (-e) moving in two dimensions and confined by a Coulomb potential, resulting from a displaced positive charge Ze is discussed. This is a classical model system for atoms. We obtain the configurations of charged particles which, depending on the value of N and Z, may result in ring structures, hexagonal-type configurations, and for N/Z approximate to 1 in an inner structure of particles which is separated by an outer ring of particles. For N/Z << 1, the Hamiltonian of the parabolic confinement case is recovered. For N/Z approximate to 1, the configurations are very different from those found in the case of a parabolic confinement potential. A hydrodynamic analysis is presented in order to highlight the correlations effects. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
Woodbury (NY) |
Editor |
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Language |
|
Wos |
000182825400087 |
Publication Date |
2003-04-03 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1063-651X;1095-3787; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.366 |
Times cited |
14 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.366; 2003 IF: 2.202 |
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|
Call Number |
UA @ lucian @ c:irua:104123 |
Serial |
3273 |
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Permanent link to this record |
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Author |
Bogaerts, A.; Grozeva, M. |
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Title |
Effect of helium/argon gas ratio in a He-Ar-Cu+ IR hollow-cathode discharge laser : modeling study and comparison with experiments |
Type |
A1 Journal article |
|
Year |
2003 |
Publication |
Applied physics B : lasers and optics |
Abbreviated Journal |
Appl Phys B-Lasers O |
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Volume |
76 |
Issue |
3 |
Pages |
299-306 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
The He-Ar-Cu+ IR laser operates in a hollow-cathode discharge, typically in a mixture of helium with a few-% Ar. The population inversion of the Cu+ ion levels, responsible for laser action, is attributed to asymmetric charge transfer between He+ ions and sputtered Cu atoms. The Ar gas is added to promote sputtering of the Cu cathode. In this paper, a hybrid modeling network consisting of several different models for the various plasma species present in a He-Ar-Cu hollow-cathode discharge is applied to investigate the effect of Ar concentration in the gas mixture on the discharge behavior, and to find the optimum He/Ar gas ratio for laser operation. It is found that the densities of electrons, Ar+ ions, Ar-m* metastable atoms, sputtered Cu atoms and Cu+ ions increase upon the addition of more Ar gas, whereas the densities of He+ ions, He-2(+) ions and He-m* metastable atoms drop considerably. The product of the calculated Cu atom and He+ ion densities, which determines the production rate of the upper laser levels, and hence probably also the laser output power, is found to reach a maximum around 1-5% Ar addition. This calculation result is compared to experimental measurements, and reasonable agreement has been reached. |
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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 |
Berlin |
Editor |
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Language |
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Wos |
000182758000017 |
Publication Date |
2004-03-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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|
ISSN |
0946-2171;1432-0649; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
1.696 |
Times cited |
6 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 1.696; 2003 IF: 2.012 |
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|
Call Number |
UA @ lucian @ c:irua:104125 |
Serial |
812 |
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Permanent link to this record |
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Author |
Peeters, F.M.; Vasilopoulos, P.; Shi, J. |
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Title |
Density of states and Fermi level of a periodically modulated two-dimensional electron gas |
Type |
A1 Journal article |
|
Year |
2002 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
14 |
Issue |
38 |
Pages |
8803-8816 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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|
Abstract |
Explicit analytic expressions are obtained for the density of states D(E) and Fermi energy E-F of a two-dimensional electron gas in the presence of a weak and periodic unidirectional electric or magnetic modulation and of a uniform perpendicular magnetic field B. The Landau levels broaden into bands and their width, proportional to the modulation strength, oscillates with B and gives rise to Weiss oscillations in D(E), E-F and the transport coefficients. When both electric and magnetic modulations are present the position of the resulting oscillations depends on the ratio delta between the two modulation strengths. When the modulations are out of phase there is no shift in the position of the oscillations when delta varies and for a particular value of delta the oscillations are suppressed. |
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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 |
000178678400008 |
Publication Date |
2002-09-18 |
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Series Editor |
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Series Title |
|
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 |
8 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.649; 2002 IF: 1.775 |
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|
Call Number |
UA @ lucian @ c:irua:104140 |
Serial |
640 |
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Permanent link to this record |
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Author |
Vodolazov, D.Y.; Baelus, B.J.; Peeters, F.M. |
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Title |
Stationary-phase slip state in quasi-one-dimensional rings |
Type |
A1 Journal article |
|
Year |
2002 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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|
Volume |
66 |
Issue |
5 |
Pages |
054531-54536 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The nonuniform superconducting state in a ring in which the order parameter vanishing at one point is studied. This state is characterized by a jump of the phase by pi at the point where the order parameter becomes zero. In uniform rings such a state is a saddle-point state and consequently unstable. However, for nonuniform rings with, e.g., variations of geometrical or physical parameters or with attached wires this state can be stabilized and may be realized experimentally. |
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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 |
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Editor |
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Language |
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Wos |
000177873000137 |
Publication Date |
2002-10-01 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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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 |
29 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.836; 2002 IF: NA |
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|
Call Number |
UA @ lucian @ c:irua:104147 |
Serial |
3152 |
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Permanent link to this record |
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Author |
Fleurov, V.; Ivanov, V.A.; Peeters, F.M.; Vagner, I.D. |
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Title |
Spin-engineered quantum dots |
Type |
A1 Journal article |
|
Year |
2002 |
Publication |
Physica. E: Low-dimensional systems and nanostructures |
Abbreviated Journal |
Physica E |
|
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Volume |
14 |
Issue |
4 |
Pages |
361-365 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Spatially nonhomogeneously spin polarized nuclei are proposed as a new mechanism to monitor electron states in a nanostructure, or as a means to create and, if necessary, reshape such nanostructures in the course of the experiment. We found that a polarization of nuclear spins may lift the spin polarization of the electron states in a nanostructure and, if sufficiently strong, leads to a polarization of the electron spins. Polarized nuclear spins may form an energy landscape capable of binding electrons with energy up to several meV and the localization radius > 100 Angstrom. (C) 2002 Elsevier Science B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
North-Holland |
Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000177511900003 |
Publication Date |
2002-10-15 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
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ISSN |
1386-9477; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.221 |
Times cited |
12 |
Open Access |
|
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|
Notes |
|
Approved |
Most recent IF: 2.221; 2002 IF: 1.107 |
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Call Number |
UA @ lucian @ c:irua:104150 |
Serial |
3088 |
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Permanent link to this record |
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Author |
Anisimovas, E.; Peeters, F.M. |
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Title |
Correlated few-particle states in artificial bipolar molecule |
Type |
A1 Journal article |
|
Year |
2002 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
|
Volume |
65 |
Issue |
23 |
Pages |
233302-233304 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We investigate the ground and excited states of a bipolar artificial molecule composed of two vertically coupled quantum dots containing different type of carriers-electrons and holes-in equilibrium. The approach based on exact diagonalization is used and reveals an intricate pattern of ground-state angular momentum switching and a rearrangement of approximate single-particle levels as a function of the interdot coupling strength. |
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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 |
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Editor |
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Language |
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Wos |
000176767900019 |
Publication Date |
2002-07-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
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ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
14 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.836; 2002 IF: NA |
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|
Call Number |
UA @ lucian @ c:irua:104154 |
Serial |
519 |
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Permanent link to this record |
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Author |
Tokei, Z.; Lanckmans, F.; van den Bosch, G.; Van Hove, M.; Maex, K.; Bender, H.; Hens, S.; van Landuyt, J. |
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Title |
Reliability of copper dual damascene influenced by pre-clean |
Type |
P1 Proceeding |
|
Year |
2002 |
Publication |
Analysis Of Integrated Circuits |
Abbreviated Journal |
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Volume |
|
Issue |
|
Pages |
118-123 |
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Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Ieee |
Place of Publication |
New york |
Editor |
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Language |
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Wos |
000177689400022 |
Publication Date |
2003-06-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
|
Times cited |
5 |
Open Access |
|
|
|
Notes |
Conference name: |
Approved |
Most recent IF: NA |
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|
Call Number |
UA @ lucian @ c:irua:104170 |
Serial |
2865 |
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Permanent link to this record |
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Author |
Lei, C.H.; Van Tendeloo, G.; Siegert, M.; Schubert, J.; Buchal, C. |
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Title |
Structural investigation of the epitaxial yittria-stabilized zirconia films deposited on (001) silicon by laser ablation |
Type |
A1 Journal article |
|
Year |
2001 |
Publication |
Journal of crystal growth |
Abbreviated Journal |
J Cryst Growth |
|
|
Volume |
222 |
Issue |
3 |
Pages |
558-564 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Yittria-stabilized zirconia (YSZ) films doped with 3 and 9 vol%. Y(2)O(3), respectively, are epitaxially deposited on (0 0 1) silicon substrates by means of pulsed laser deposition (PLD) technique. Transmission electron microscopy (TEM) and X-ray diffraction are mainly combined to study the film microstructure. It is: found that the film structure strongly depends on the amount of Y(2)O(3) dopant. 99/0 Y(2)O(3)-doped films display a near cubic structure; 45 degrees 1/2(1 1 0) dislocations are the main defects in the film and thermal cracks are formed during cooling. The 3% Y(2)O(3)-doped films are dominated by {1 1 0} twin-related tetragonal domains in which monoclinic phase is found. The films are free of thermal cracks even for films thicker than 2 mum. (C) 2001 Elsevier Science B.V. All rights reserved. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Amsterdam |
Editor |
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Language |
|
Wos |
000166701500020 |
Publication Date |
2002-07-25 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0022-0248; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
1.751 |
Times cited |
12 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 1.751; 2001 IF: 1.283 |
|
|
Call Number |
UA @ lucian @ c:irua:104211 |
Serial |
3240 |
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Author |
Schuddinck, W.; Van Tendeloo, G.; Barnabé, A.; Hervieu, M.; Raveau, B. |
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Title |
Relation between structure, charge ordering and magnetotransport properties in Nd0.5Ca0.5Mn1-xCrxO3 manganites |
Type |
A1 Journal article |
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Year |
2000 |
Publication |
Journal of magnetism and magnetic materials
T2 – Symposium G Material Physics Issues and Applications of Magnetic Oxides, at the E-MRS Spring Meeting, JUN 01-04, 1999, Strasbourg, France |
Abbreviated Journal |
J Magn Magn Mater |
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Volume |
211 |
Issue |
1-3 |
Pages |
105-110 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The relationships between incommensurability, charge ordering and magnetotransport properties in Nd0.5Ca0.5Mn1-xCrxO3 manganites have been studied by electron diffraction and lattice imaging versus temperature with 0.02 less than or equal to x less than or equal to 0.07. All compositions show an incommensurate superstructure over the whole temperature domain, despite the fact that they are ferromagnetic and conductive below 140 K, The q-vector (1/2 – delta)a* decreases with increasing temperature for all compositions x. For a given temperature q also decreases with x. Lattice images obtained at low temperature give a clear view of the characteristics of the incommensurate structure. They also provide a better understanding of the charge ordering process. The low-temperature form of the Cr-doped manganites is not a perfectly doubled cell [[2a(p)root 2 x 2a(p) x a(p)root 2]], but defects inducing a tripled cell occur pseudo-periodically. (C) 2000 Elsevier Science B.V. All rights reserved. |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000085772100017 |
Publication Date |
2002-07-25 |
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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 |
0304-8853; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.63 |
Times cited |
16 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.63; 2000 IF: 0.996 |
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Call Number |
UA @ lucian @ c:irua:104256 |
Serial |
2858 |
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Permanent link to this record |
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Author |
Maignan, A.; Martin, C.; Van Tendeloo, G.; Hervieu, M.; Raveau, B. |
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Title |
Size mismatch : a crucial factor for generating a spin-glass insulator in manganites |
Type |
A1 Journal article |
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Year |
1999 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
60 |
Issue |
22 |
Pages |
15214-15219 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Thr structural, electronic, and magnetic properties of the highly mismatched perovskite oxides, Th(0.35)A(0.65)MnO(3), where Ais for the alkaline earth divalent cations (Ca, Ba, Sr), which are all characterized by the same large tolerance factor (t=0.934), have been investigated by using electron microscopy, electrical resistivity, magnetic susceptibility, and magnetization. It is clearly established that a transition from ferromagnetic metallic towards spin-glass insulator samples is induced as the A-site cationic size mismatch is increased. Moreover, the magnetoresistance (MR) properties of these manganites are strongly reduced for the spin-glass insulators, demonstrating that the A-sire cationic disorder is detrimental for the colossal MR properties. Based on these results, a new electronic and magnetic diagram is established that shows that the A-site disorder, rather than the A-site average cationic size (or t) is the relevant factor for generating spin-glass insulating manganites. [S0163-1829(99)01746-4]. |
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Place of Publication |
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Wos |
000084631600039 |
Publication Date |
2002-07-27 |
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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 |
0163-1829;1095-3795; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
75 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 1999 IF: NA |
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Call Number |
UA @ lucian @ c:irua:104280 |
Serial |
3038 |
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Author |
Shi, J.M.; Koenraad, P.M.; van de Stadt, A.F.W.; Peeters, F.M.; Devreese, J.T.; Wolter, J.H. |
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Title |
Electronic structure of a Si \delta-doped layer in a GaAs/AlxGa1-xAs/GaAs quantum barrier |
Type |
A1 Journal article |
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Year |
1996 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
54 |
Issue |
11 |
Pages |
7996-8004 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
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Abstract |
We present a theoretical study of the electronic structure of a heavily Si delta-doped layer in a GaAs/AlxGa1-xAs/GaAs quantum barrier. In this class of structures the effect of DX centers on the electronic properties can be tuned by changing the AlxGa1-xAs barrier width and/or the Al concentration, which leads to a lowering of the DX level with respect to the Fermi energy without disturbing the wave functions much. A self-consistent approach is developed in which the effective confinement potential and the Fermi energy of the system, the energies, the wave functions, and the electron densities of the discrete subbands have been obtained as a function of both the material parameters of the samples and the experimental conditions. The effect of DX centers on such structures at nonzero temperature and under an external pressure is investigated for three different models: (1) the DX(nc)(0) model with no correlation effects, (2) the d(+)/DX(0) model, and (3) the d(+)/DX(-) model with inclusion of correlation effects. In the actual calculation, influences of the background accepters, the discontinuity of the effective mass of the electrons at the interfaces of the different materials, band nonparabolicity, and the exchange-correlation energy of the electrons have been taken into account. We have found that (1) introducing a quantum barrier into delta-doped GaAs makes it possible to control the energy gaps between different electronic; subbands; (2) the electron wave functions are mon spread out when the repellent effect of the barriers is increased as compared to those in delta-doped GaAs; (3) increasing the quantum-barrier height and/or the application of hydrostatic pressure are helpful to experimentally observe the effect of the DX centers through a decrease of the total free-electron density; and (4) the correlation effects of the charged impurities are important for the systems under study. |
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Place of Publication |
Lancaster, Pa |
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Wos |
A1996VL14500066 |
Publication Date |
2002-07-27 |
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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 |
0163-1829;1095-3795; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.736 |
Times cited |
11 |
Open Access |
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no |
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Call Number |
UA @ lucian @ c:irua:104388 |
Serial |
1012 |
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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. |
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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 |
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Year |
1995 |
Publication |
The journal of physics and chemistry of solids |
Abbreviated Journal |
J Phys Chem Solids |
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Volume |
56 |
Issue |
10 |
Pages |
1471-1478 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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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. |
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Place of Publication |
New York, N.Y. |
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Wos |
A1995RR95600025 |
Publication Date |
2002-07-26 |
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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 |
0022-3697; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.853 |
Times cited |
16 |
Open Access |
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Notes |
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no |
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Call Number |
UA @ lucian @ c:irua:104423 |
Serial |
574 |
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Author |
Huve, M.; Martin, C.; Maignan, A.; Michel, C.; Van Tendeloo, G.; Hervieu, M.; Raveau, B. |
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Title |
A new cuprate with mercury bilayers : the “2222” oxide Hg2-xMxBa2Pr2Cu2O10-\delta (M= Cu,Pr) |
Type |
A1 Journal article |
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Year |
1995 |
Publication |
Journal of solid state chemistry |
Abbreviated Journal |
J Solid State Chem |
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Volume |
114 |
Issue |
1 |
Pages |
230-235 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A ''2222'' cuprate with mercury bilayers (Hg1.5Cu0.2Pr0.3)Ba2Pr2Cu2O10-delta, has been synthesized for the first time. It crystallizes in the P4/nmm space group with a = 3.9072(1) Angstrom and c = 17.219(1) Angstrom. The powder XRD and HREM studies of this new cuprate show that its structure consists of an intergrowth of double pyramidal (oxygen-deficient perovskite) copper layers, with double fluorite-type layers and distorted triple rock salt layers (mercury bilayers). The structure of this phase can be deduced from that of the ''2212'' mercury cuprate (Hg1.5Cu0.2Pr0.3)Ba2PrCu2O8-delta by the introduction of one additional [PrO2]infinity fluorite layer. The regular stacking of the metallic layer and the uniform cationic distribution in the mercury bilayers are remarkable features of this cuprate. The stabilization of the mercury bilayers by praseodymium and the absence of superconductivity are discussed. (C) 1995 Academic Press, Inc. |
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Place of Publication |
London |
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Wos |
A1995QA17000033 |
Publication Date |
2002-10-07 |
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Series Issue |
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Edition |
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ISSN |
0022-4596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.133 |
Times cited |
6 |
Open Access |
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Notes |
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Approved |
PHYSICS, APPLIED 28/145 Q1 # |
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Call Number |
UA @ lucian @ c:irua:104448 |
Serial |
2310 |
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Author |
Martin, C.; Hervieu, M.; Huvé, M.; Michel, C.; Maignan, A.; Van Tendeloo, G.; Raveau, B. |
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Title |
Lead-mercury-based superconductors – the 1212-cuprate Pb0.7Hg0.3Sr2+xCa0.7Nd0.3-xCu2O7-\delta and the new oxycarbonate Pb0.7Hg0.3Sr4Cu2CO3O7 |
Type |
A1 Journal article |
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Year |
1994 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
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Volume |
222 |
Issue |
1-2 |
Pages |
19-26 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
A new superconducting mercury oxycarbonate, Pb0.7Hg0.3Sr4Cu2CO3O7, has been synthesized. This tetragonal phase (a = 3.824 angstrom, c= 16.468 angstrom) consists of an intergrowth of two nonsuperconducting compounds, Sr2CuO2CO3 and Pb0.7Hg0.3Sr2CuO5. It exhibits after optimization a critical temperature of 70 K, with a sharp transition and a superconducting volume fraction of 50%. Its behavior can be compared to that of thallium oxycarbonates previously isolated. This study is completed by a reinvestigation of the 1212 cuprate of the system Hg-Pb-Sr-Ca-Nd-Cu. A superconducting phase with the 1212 structure, similar to that previously obtained but with a significantly different composition, Pb0.7Hg0.3Sr2+xCa0.7Nd0.3-xCu2O7, has been obtained, with a T(c onset) of 100 K. The behavior of the latter is compared with other lead-based 1212 cuprates. |
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Publisher |
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Place of Publication |
Amsterdam |
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Wos |
A1994NB49400004 |
Publication Date |
2002-10-17 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0921-4534; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
0.942 |
Times cited |
49 |
Open Access |
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Notes |
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no |
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Call Number |
UA @ lucian @ c:irua:104517 |
Serial |
1813 |
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Author |
Vanhellemont, J.; Maes, H.E.; Schaekers, M.; Armigliato, A.; Cerva, H.; Cullis, A.; de Sande, J.; Dinges, H.; Hallais, J.; Nayar, V.; Pickering, C.; Stehlé, J.L.; Van Landuyt, J.; Walker, C.; Werner, H.; Salieri, P.; |
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Title |
Round-robin investigation of silicon-oxide on silicon reference materials for ellipsometry |
Type |
A1 Journal article |
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Year |
1993 |
Publication |
Applied surface science
T2 – SYMP ON DIAGNOSTIC TECHNIQUES FOR SEMICONDUCTOR MATERIALS ANALYSIS AND, FABRICATION PROCESS CONTROL, AT THE 1992 SPRING CONF OF THE EUROPEAN, MATERIALS RESEARCH SOC, JUN 02-05, 1992, STRASBOURG, FRANCE |
Abbreviated Journal |
Appl Surf Sci |
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Volume |
63 |
Issue |
1-4 |
Pages |
45-51 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
The main results and conclusions are presented of a round robin study of silicon oxide on silicon reference samples for ellipsometry. The oxide films with nominal thicknesses of 10, 50 and 120 nm are grown by thermal oxidation. The oxide film thicknesses have been determined by single wavelength ellipsometry (SWE), by spectroscopic ellipsometry (SE) and by cross-sectional conventional and high-resolution transmission electron microscopy (TEM and HREM) in different laboratories. The main conclusions are that special precautions have to be taken in order to use TEM as a reliable thickness measurement technique; that single wavelength ellipsometry can be used with great accuracy and reproducibility for the 50 and 120 nm film thicknesses but that it shows some inherent problems for the 10 nm films; and that spectroscopic ellipsometry showed for all film thicknesses an accuracy and reproducibility which is clearly superior to that of SWE. |
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Publisher |
Elsevier science bv |
Place of Publication |
Amsterdam |
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Wos |
A1993KF03400009 |
Publication Date |
2002-10-16 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0169-4332; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.711 |
Times cited |
13 |
Open Access |
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Notes |
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Call Number |
UA @ lucian @ c:irua:104539 |
Serial |
2932 |
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