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Author |
Badalyan, S.M.; Peeters, F.M. |
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Title |
Effect of nonhomogenous dielectric background on the plasmon modes in graphene double-layer structures at finite temperatures |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
19 |
Pages |
195444-195444,6 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We have calculated the plasmon modes in graphene double layer structures at finite temperatures, taking into account the inhomogeneity of the dielectric background of the system. The effective dielectric function is obtained from the solution of the Poisson equation of a three-layer dielectric medium with graphene sheets located at the interfaces, separating the different materials. Due to the momentum dispersion of the effective dielectric function, the intra- and interlayer bare Coulomb interactions in the graphene double layer system acquires an additional momentum dependence-an effect that is of the order of the interlayer interaction itself. We show that the energies of the in-phase and out-of-phase plasmon modes are determined largely by different values of the spatially dependent effective dielectric function. The effect of the dielectric inhomogeneity increases with temperature, and even at high temperatures the energy shift induced by the dielectric inhomogeneity and temperature itself remains larger than the broadening of the plasmon energy dispersions due to the Landau damping. The obtained new features of the plasmon dispersions can be observed in frictional drag measurements and in inelastic light scattering and electron energy-loss spectroscopies. |
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Wos |
000304394800011 |
Publication Date |
2012-05-23 |
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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 |
67 |
Open Access |
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Notes |
; We thank G. Vignale for useful discussions and acknowledge support from the Flemisch Science Foundation (FWO-Fl) and the Belgian Science Policy (BELSPO). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:98941 |
Serial |
826 |
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Permanent link to this record |
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Author |
Tarakina, N.V.; Verberck, B. |
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Title |
Tubular fullerenes in carbon nanotubes |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Fullerenes, nanotubes, and carbon nanostructures |
Abbreviated Journal |
Fuller Nanotub Car N |
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Volume |
20 |
Issue |
4-7 |
Pages |
538-542 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
We investigate the optimal orientations and positions of tubular fullerene molecules C-70, C-80 and C-90 encapsulated in single-walled carbon nanotubes (SWCNTs). We find that increasing the tube radius leads to the following succession of energetically stable regimes: 1) lying molecules positioned on the tube's long axis, 2) tilted molecules on the tube's long axis and 3) lying molecules shifted away from the tube's long axis. In the case of C-70 and C-80 molecules, standing on-axis configurations also occur. Our findings are relevant for the possible application of molecular-orientation-dependent electronic properties of fullerene nanopeapods. |
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Wos |
000304297500045 |
Publication Date |
2012-05-14 |
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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 |
1536-383X;1536-4046; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.35 |
Times cited |
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Open Access |
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Notes |
; This work was financially supported by the Research Foundation – Flanders (FWO-Vl). B. V. is a Postdoctoral Fellow of the Research Foundation-Flanders (FWO-Vl). ; |
Approved |
Most recent IF: 1.35; 2012 IF: 0.764 |
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Call Number |
UA @ lucian @ c:irua:99004 |
Serial |
3737 |
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Permanent link to this record |
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Author |
Verberck, B.; Cambedouzou, J.; Vliegenthart, G.A.; Gompper, G.; Launois, P. |
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Title |
Monte Carlo studies of C60- and C70-peapods |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Fullerenes, nanotubes, and carbon nanostructures |
Abbreviated Journal |
Fuller Nanotub Car N |
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Volume |
20 |
Issue |
4/7 |
Pages |
371-377 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
We present results of Monte Carlo simulations of chains of C-60 and chains of C-70 molecules encapsulated in a single-walled carbon nanotube (SWCNT). We observe the changes in the configuration of the fullerene molecules when varying tube radius and temperature. In particular, the evolution of the pair correlation functions reveal a transition from linear harmonic chain behavior to a hard-sphere liquid upon heating, demonstrating the possibility of tuning properties of C-60- and C-70@SWCNT peapods with radius and temperature. |
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Place of Publication |
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Wos |
000304297500015 |
Publication Date |
2012-05-14 |
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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 |
1536-383X;1536-4046; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.35 |
Times cited |
1 |
Open Access |
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Notes |
; Helpful discussions with K. H. Michel, P.-A. Albouy and C. Bousige are gratefully acknowledged. This work was financially supported by the Research Foundation-Flanders (FWO-Vl). ; |
Approved |
Most recent IF: 1.35; 2012 IF: 0.764 |
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Call Number |
UA @ lucian @ c:irua:99003 |
Serial |
2200 |
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Permanent link to this record |
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Author |
Grimaldi, G.; Leo, A.; Nigro, A.; Silhanek, A.V.; Verellen, N.; Moshchalkov, V.V.; Milošević, M.V.; Casaburi, A.; Cristiano, R.; Pace, S. |
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Title |
Controlling flux flow dissipation by changing flux pinning in superconducting films |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
100 |
Issue |
20 |
Pages |
202601-202601,4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We study the flux flow state in superconducting materials characterized by rather strong intrinsic pinning, such as Nb, NbN, and nanostructured Al thin films, in which we drag the superconducting dissipative state into the normal state by current biasing. We modify the vortex pinning strength either by ion irradiation, by tuning the measuring temperature or by including artificial pinning centers. We measure critical flux flow voltages for all materials and the same effect is observed: switching to low flux flow dissipations at low fields for an intermediate pinning regime. This mechanism offers a way to additionally promote the stability of the superconducting state. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4718309] |
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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 |
000304265000051 |
Publication Date |
2012-05-14 |
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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 |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
33 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
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Call Number |
UA @ lucian @ c:irua:98946 |
Serial |
504 |
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Permanent link to this record |
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Author |
Vandenberghe, W.G.; Verhulst, A.S.; Kao, K.-H.; De Meyer, K.; Sorée, B.; Magnus, W.; Groeseneken, G. |
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Title |
A model determining optimal doping concentration and material's band gap of tunnel field-effect transistors |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
100 |
Issue |
19 |
Pages |
193509-193509,4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We develop a model for the tunnel field-effect transistor (TFET) based on the Wentzel-Kramer-Brillouin approximation which improves over existing semi-classical models employing generation rates. We hereby introduce the concept of a characteristic tunneling length in direct semiconductors. Based on the model, we show that a limited density of states results in an optimal doping concentration as well as an optimal material's band gap to obtain the highest TFET on-current at a given supply voltage. The observed optimal-doping trend is confirmed by 2-dimensional quantum-mechanical simulations for silicon and germanium. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4714544] |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
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Language |
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Wos |
000304108000098 |
Publication Date |
2012-05-12 |
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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 |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
25 |
Open Access |
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Notes |
; William Vandenberghe gratefully acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). This work was supported by IMEC's Industrial Affiliation Program. ; |
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
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Call Number |
UA @ lucian @ c:irua:98948 |
Serial |
2105 |
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Permanent link to this record |
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Author |
Komendová, L.; Chen, Y.; Shanenko, A.A.; Milošević, M.V.; Peeters, F.M. |
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Title |
Two-band superconductors : hidden criticality deep in the superconducting state |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
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Volume |
108 |
Issue |
20 |
Pages |
207002-207002,5 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We show that two-band superconductors harbor hidden criticality deep in the superconducting state, stemming from the critical temperature of the weaker band taken as an independent system. For sufficiently small interband coupling gamma the coherence length of the weaker band exhibits a remarkable deviation from the conventional monotonic increase with temperature, namely, a pronounced peak close to the hidden critical point. The magnitude of the peak scales as proportional to gamma(-mu), with the Landau critical exponent mu = 1/3, the same as found for the mean-field critical behavior with respect to the source field in ferromagnets and ferroelectrics. Here reported hidden criticality of multiband superconductors can be experimentally observed by, e.g., imaging of the variations of the vortex core in a broader temperature range. Similar effects are expected for the superconducting multilayers. |
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Place of Publication |
New York, N.Y. |
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Wos |
000304064000017 |
Publication Date |
2012-05-15 |
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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 |
0031-9007;1079-7114; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
8.462 |
Times cited |
75 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). Useful discussions with A. V. Vagov are acknowledged. ; |
Approved |
Most recent IF: 8.462; 2012 IF: 7.943 |
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Call Number |
UA @ lucian @ c:irua:98945 |
Serial |
3770 |
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Permanent link to this record |
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Author |
Djotyan, A.P.; Avetisyan, A.A.; Hao, Y.L.; Peeters, F.M. |
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Title |
Shallow donor near a semiconductor surface in the presence of locally spherical scanning tunneling microscope tip |
Type |
P1 Proceeding |
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Year |
2012 |
Publication |
Proceedings of the Society of Photo-optical Instrumentation Engineers
T2 – Conference on Photonics and Micro and Nano-structured Materials, JUN 28-30, 2011, Yerevan, ARMENIA |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
84140-84148 |
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Keywords |
P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
We developed a variational approach to investigate the ground state energy and the extend of the wavefunction of a neutral donor located near a semiconductor surface in the presence of scanning tunneling microscope (STM) metallic tip. We apply the effective mass approximation and use a variational wavefunction that takes into account the influence of all image charges that arise due to the presence of a metallic tip. The behavior of the ground state energy when the tip approaches the semiconductor surface is investigated. |
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Wos |
000303856600020 |
Publication Date |
2012-01-20 |
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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 |
8414 |
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 |
; This work was supported by the Flemish Science Foundation (FWO-Vl), and the Belgian Science Policy. One of us (AAA) was supported by a fellowship from the Belgian Federal Science Policy Office (Belspo). ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:113047 |
Serial |
2987 |
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Permanent link to this record |
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Author |
Avetisyan, A.A.; Partoens, B.; Peeters, F.M. |
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Title |
Electric field tuning of the band gap in four layers of graphene with different stacking order |
Type |
P1 Proceeding |
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Year |
2012 |
Publication |
Proceedings of the Society of Photo-optical Instrumentation Engineers
T2 – Conference on Photonics and Micro and Nano-structured Materials, JUN 28-30, 2011, Yerevan, ARMENIA |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
84140-84148 |
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Keywords |
P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
We investigated the effect of different stacking order of the four graphene layer system on the induced band gap when positively charged top and negatively charged back gates are applied to the system. A tight-binding approach within a self-consistent Hartree approximation is used to calculate the induced charges on the different graphene layers. We show that the electric field does not open an energy gap if the multilayer graphene system contains a trilayer part with the ABA Bernal stacking. |
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Wos |
000303856600012 |
Publication Date |
2012-01-20 |
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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 |
8414 |
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 |
; This work was supported by the Flemish Science Foundation (FWO-Vl), and the BelgianScience Policy (IAP). One of us (A.A.A.) was supported by a fellowship from the Belgian Federal Science Policy Office (BELSPO). ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:113046 |
Serial |
886 |
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Permanent link to this record |
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Author |
Li, Z.; Covaci, L.; Marsiglio, F. |
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Title |
Impact of Dresselhaus versus Rashba spin-orbit coupling on the Holstein polaron |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
20 |
Pages |
205112-205112,5 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We utilize an exact variational numerical procedure to calculate the ground-state properties of a polaron in the presence of Rashba and linear Dresselhaus spin-orbit coupling. We find that when the linear Dresselhaus spin-orbit coupling approaches the Rashba spin-orbit coupling, the Van Hove singularity in the density of states will be shifted away from the bottom of the band and finally disappear when the two spin-orbit couplings are tuned to be equal. The effective mass will be suppressed; the trend will become more significant for low phonon frequency. The presence of two dominant spin-orbit couplings will make it possible to tune the effective mass with more varied observables. |
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Wos |
000303794900003 |
Publication Date |
2012-05-09 |
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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 |
18 |
Open Access |
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Notes |
; This work was supported in part by the Natural Sciences and Engineering Research Council of Canada (NSERC), by ICORE (Alberta), by the Flemish Science Foundation (FWO-Vl), and by the Canadian Institute for Advanced Research (CIfAR). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:99121 |
Serial |
1558 |
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Permanent link to this record |
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Author |
Misko, V.R.; Nori, F. |
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Title |
Magnetic flux pinning in superconductors with hyperbolic-tesselation arrays of pinning sites |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
18 |
Pages |
184506-184506,6 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We study magnetic flux interacting with arrays of pinning sites (APSs) placed on vertices of hyperbolic tesselations (HTs). We show that, due to the gradient in the density of pinning sites, HT APSs are capable of trapping vortices for a broad range of applied magnetic fluxes. Thus, the penetration of magnetic field in HT APSs is essentially different from the usual scenario predicted by the Bean model. We demonstrate that, due to the enhanced asymmetry of the surface barrier for vortex entry and exit, this HT APS could be used as a “capacitor” to store magnetic flux. |
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Place of Publication |
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Editor |
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Language |
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Wos |
000303653600005 |
Publication Date |
2012-05-04 |
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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 |
24 |
Open Access |
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Notes |
; V.R.M. acknowledges support from the “Odysseus” Program of the Flemish Government & FWO-Vl, and the IAP. F.N. is partially supported by the ARO, NSF Grant No. 0726909, JSPS-RFBR Contract No. 12-02-92100, Grant-in-Aid for Scientific Research (S), MEXT Kakenhi on Quantum Cybernetics, and the JSPS via its FIRST program. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:98224 |
Serial |
1880 |
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Permanent link to this record |
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Author |
Berdiyorov, G.R.; de Romaguera, A.R.C.; Milošević, M.V.; Doria, M.M.; Covaci, L.; Peeters, F.M. |
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Title |
Dynamic and static phases of vortices under an applied drive in a superconducting stripe with an array of weak links |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
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Volume |
85 |
Issue |
4 |
Pages |
130-130,8 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Static and dynamic properties of superconducting vortices in a superconducting stripe with a periodic array of weakly-superconducting (or normal metal) regions are studied in the presence of external magnetic and electric fields. The time-dependent Ginzburg-Landau theory is used to describe the electronic transport, where the anisotropy is included through the spatially-dependent critical temperature T-c. Superconducting vortices penetrating into the weak-superconducting region with smaller T-c are more mobile than the ones in the strong superconducting regions. We observe periodic entrance and exit of vortices which reside in the weak link for some short interval. The mobility of the weakly-pinned vortices can be reduced by increasing the uniform applied magnetic field leading to distinct features in the voltage vs. magnetic field response of the system. |
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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 |
000303545400013 |
Publication Date |
2012-04-20 |
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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 |
1434-6028;1434-6036; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.461 |
Times cited |
32 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the bilateral programme between Flanders and Brazil. G.R.B. and L.C. acknowledge individual support from FWO-Vl. A.R.de C.R. acknowledges CNPq and FACEPE for financial support. ; |
Approved |
Most recent IF: 1.461; 2012 IF: 1.282 |
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Call Number |
UA @ lucian @ c:irua:98267 |
Serial |
761 |
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Permanent link to this record |
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Author |
Grujić, M.; Zarenia, M.; Tadić, M.; Peeters, F.M. |
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Title |
Interband optical absorption in a circular graphene quantum dot |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physica scripta |
Abbreviated Journal |
Phys Scripta |
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Volume |
T149 |
Issue |
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Pages |
014056-014056,4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We investigate the energy levels and optical properties of a circular graphene quantum dot in the presence of an external magnetic field perpendicular to the dot. Based on the Dirac-Weyl equation and assuming zero outward current at the edge of the dot we present the results for two different types of boundary conditions, i.e. infinite-mass (IMBC) and zigzag boundary conditions. We found that the dot with zigzag edges displays a zero-energy state in the energy spectra while this is not the case for the IMBCs. For both boundary conditions, the confinement becomes dominated by the magnetic field, where the energy levels converge to the Landau levels as the magnetic field increases. The effect of boundary conditions on the electron-and hole-energy states is found to affect the interband absorption spectra, where we found larger absorption in the case of IMBCs. The selection rules for interband optical transitions are determined and discussed for both boundary conditions. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Stockholm |
Editor |
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Language |
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Wos |
000303523500057 |
Publication Date |
2012-04-27 |
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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 |
0031-8949;1402-4896; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.28 |
Times cited |
5 |
Open Access |
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Notes |
; This work was supported by the EuroGraphene program of the ESF (project CONGRAN), the Ministry of Education and Science of Serbia, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 1.28; 2012 IF: 1.032 |
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Call Number |
UA @ lucian @ c:irua:99136 |
Serial |
1688 |
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Permanent link to this record |
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Author |
Arsoski, V.; Čukarić, N.; Tadić, M.; Peeters, F.M. |
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Title |
Exciton states in a nanocup in the presence of a perpendicular magnetic field |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physica scripta |
Abbreviated Journal |
Phys Scripta |
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Volume |
T149 |
Issue |
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Pages |
014054-014054,5 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The exciton states in a strained (In,Ga)As/GaAs nanocup are theoretically determined. We explore how the nanocup bottom thickness (t) affects the magnetic field dependence of the exciton energy. Strain distribution is computed by the continuum mechanical model under the approximation of isotropic elasticity. The exciton wave functions are expanded into products of the electron and hole envelope functions. For small t, the exciton ground state has zero orbital momentum and exhibits small oscillations of the second derivative when the magnetic field increases. When t approaches the value of the cup height, however, the exciton levels exhibit angular momentum transitions, whose behavior is similar to that for type-II quantum dots. Small oscillations of the oscillator strength for exciton recombination are found when the magnetic field increases. An increase in thickness of the nanocup bottom has only a small effect on those oscillations for the optically active exciton states, but the exciton ground state becomes dark when the magnetic field increases. Hence, the results of our calculations show that an increase in thickness of the nanocup bottom transforms the exciton ground energy level dependence on magnetic field from the one characteristic of type-I rings to the one characteristic of type-II dots. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Stockholm |
Editor |
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Language |
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Wos |
000303523500055 |
Publication Date |
2012-04-27 |
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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 |
0031-8949;1402-4896; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.28 |
Times cited |
2 |
Open Access |
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Notes |
; This work was supported by the EU Network of Excellence SANDiE, the Ministry of Education and Science of Serbia, the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 1.28; 2012 IF: 1.032 |
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Call Number |
UA @ lucian @ c:irua:99135 |
Serial |
1117 |
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Permanent link to this record |
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Author |
Dixit, H.; Saniz, R.; Cottenier, S.; Lamoen, D.; Partoens, B. |
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Title |
Electronic structure of transparent oxides with the Tran-Blaha modified Becke-Johnson potential |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
24 |
Issue |
20 |
Pages |
205503-205503,9 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
We present electronic band structures of transparent oxides calculated using the Tran-Blaha modified Becke-Johnson (TB-mBJ) potential. We studied the basic n-type conducting binary oxides In2O3, ZnO, CdO and SnO2 along with the p-type conducting ternary oxides delafossite CuXO2 (X = Al, Ga, In) and spinel ZnX2O4 (X = Co, Rh, Ir). The results are presented for calculated band gaps and effective electron masses. We discuss the improvements in the band gap determination using TB-mBJ compared to the standard generalized gradient approximation (GGA) in density functional theory (DFT) and also compare the electronic band structure with available results from the quasiparticle GW method. It is shown that the calculated band gaps compare well with the experimental and GW results, although the electron effective mass is generally overestimated. |
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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 |
000303507100009 |
Publication Date |
2012-04-27 |
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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 |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.649 |
Times cited |
113 |
Open Access |
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Notes |
Iwt; Fwo |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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Call Number |
UA @ lucian @ c:irua:98222 |
Serial |
1017 |
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Permanent link to this record |
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Author |
Chen, Y.; Shanenko, A.A.; Perali, A.; Peeters, F.M. |
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Title |
Superconducting nanofilms : molecule-like pairing induced by quantum confinement |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
24 |
Issue |
18 |
Pages |
185701-185701,8 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Quantum confinement of the perpendicular motion of electrons in single-crystalline metallic superconducting nanofilms splits the conduction band into a series of single-electron subbands. A distinctive feature of such a nanoscale multi-band superconductor is that the energetic position of each subband can vary significantly with changing nanofilm thickness, substrate material, protective cover and other details of the fabrication process. It can occur that the bottom of one of the available subbands is situated in the vicinity of the Fermi level. We demonstrate that the character of the superconducting pairing in such a subband changes dramatically and exhibits a clear molecule-like trend, which is very similar to the well-known crossover from the Bardeen-Cooper-Schrieffer regime to Bose-Einstein condensation (BCS-BEC) observed in trapped ultracold fermions. For Pb nanofilms with thicknesses of 4 and 5 monolayers (MLs) this will lead to a spectacular scenario: up to half of all the Cooper pairs nearly collapse, shrinking in the lateral size (parallel to the nanofilm) down to a few nanometers. As a result, the superconducting condensate will be a coherent mixture of almost molecule-like fermionic pairs with ordinary, extended Cooper pairs. |
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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 |
000303500900018 |
Publication Date |
2012-04-05 |
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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 |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.649 |
Times cited |
26 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). AAS thanks A Bianconi, M D Croitoru and A V Vagov for useful discussions. AAS acknowledges the hospitality and fruitful interactions with G C Strinati, P Pieri and D Neilson during his visit to the University of Camerino, supported by the School of Advanced Studies of the University of Camerino. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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Call Number |
UA @ lucian @ c:irua:98223 |
Serial |
3357 |
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Permanent link to this record |
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Author |
Lajevardipour, A.; Neek-Amal, M.; Peeters, F.M. |
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Title |
Thermomechanical properties of graphene : valence force field model approach |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
24 |
Issue |
17 |
Pages |
175303-175303,8 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Using the valence force field model of Perebeinos and Tersoff (2009 Phys. Rev. B 79 241409(R)), different energy modes of suspended graphene subjected to tensile or compressive strain are studied. By carrying out Monte Carlo simulations it is found that: (i) only for small strains (vertical bar epsilon vertical bar (sic) 0.02) is the total energy symmetrical in the strain, while it behaves completely differently beyond this threshold; (ii) the important energy contributions in stretching experiments are stretching, angle bending, an out-of-plane term, and a term that provides repulsion against pi-pi misalignment; (iii) in compressing experiments the two latter terms increase rapidly, and beyond the buckling transition stretching and bending energies are found to be constant; (iv) from stretching-compressing simulations we calculated the Young's modulus at room temperature 350 +/- 3.15 N m(-1), which is in good agreement with experimental results (340 +/- 50 N m(-1)) and with ab initio results (322-353) N m(-1); (v) molar heat capacity is estimated to be 24.64 J mol(-1) K-1 which is comparable with the Dulong-Petit value, i. e. 24.94 J mol(-1) K-1, and is almost independent of the strain; (vi) nonlinear scaling properties are obtained from height-height correlations at finite temperature; (vii) the used valence force field model results in a temperature independent bending modulus for graphene, and (viii) the Gruneisen parameter is estimated to be 0.64. |
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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 |
000303499700012 |
Publication Date |
2012-04-05 |
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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 |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.649 |
Times cited |
29 |
Open Access |
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Notes |
; We acknowledge helpful comments by V Perebeinos, S Costamagna, A Fasolino and J H Los. This work was supported by the Flemish science foundation (FWO-Vl) and the Belgium Science Policy (IAP). ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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Call Number |
UA @ lucian @ c:irua:99123 |
Serial |
3639 |
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Permanent link to this record |
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Author |
Yang, W.; Misko, V.R.; Nelissen, K.; Kong, M.; Peeters, F.M. |
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Title |
Using self-driven microswimmers for particle separation |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Soft matter |
Abbreviated Journal |
Soft Matter |
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Volume |
8 |
Issue |
19 |
Pages |
5175-5179 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Microscopic self-propelled swimmers capable of autonomous navigation through complex environments provide appealing opportunities for localization, pick-up and delivery of micro and nanoscopic objects. Inspired by motile cells and bacteria, man-made microswimmers have been fabricated, and their motion in patterned surroundings has been experimentally studied. We propose to use self-driven artificial microswimmers for the separation of binary mixtures of colloids. We revealed different regimes of separation, including one with a velocity inversion. Our findings could be of use for various biological and medical applications. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Cambridge |
Editor |
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Language |
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Wos |
000303208700009 |
Publication Date |
2012-03-26 |
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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 |
1744-683X;1744-6848; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.889 |
Times cited |
45 |
Open Access |
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Notes |
; This work was supported by the “Odysseus” Program of the Flemish Government and the Flemish Science Foundation (FWO-V1) (Belgium), the National Natural Science Foundation of China (No. 11047111), the State Key Program of National Natural Science of China (No. 51135007), the Research Fund for the Doctoral Program of Higher Education of China (No. 20111415120002), and the Major State Basic Research Development Program of China (973) (No. 2009CB724201). ; |
Approved |
Most recent IF: 3.889; 2012 IF: 3.909 |
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Call Number |
UA @ lucian @ c:irua:98326 |
Serial |
3826 |
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Permanent link to this record |
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Author |
Barbier, M.; Papp, G.; Peeters, F.M. |
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Title |
Snake states and Klein tunneling in a graphene Hall bar with a pn-junction |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
100 |
Issue |
16 |
Pages |
163121-163121,3 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The Hall (R-H) and bend (R-B) resistances of a graphene Hall bar structure containing a pn-junction are calculated when in the ballistic regime. The simulations are done using the billiard model. Introducing a pn-junction-dividing the Hall bar geometry in two regions-leads to two distinct regimes exhibiting very different physics: (1) both regions are of n-type and (2) one region is n-type and the other p-type. In regime (1), a “Hall plateau”-an enhancement of the resistance-appears for R-H. On the other hand, in regime (2), we found a negative R-H, which approaches zero for large B. The bend resistance is highly asymmetric in regime (2) and the resistance increases with increasing magnetic field B in one direction while it reduces to zero in the other direction. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4704667] |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000303128500064 |
Publication Date |
2012-04-20 |
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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 |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
20 |
Open Access |
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Notes |
; This work was supported by IMEC, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-EuroGRAPHENE project CONGRAN. ; |
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
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Call Number |
UA @ lucian @ c:irua:99129 |
Serial |
3047 |
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Permanent link to this record |
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Author |
Govaerts, K.; Sluiter, M.H.F.; Partoens, B.; Lamoen, D. |
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Title |
Stability of Sb-Te layered structures : first-principles study |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
14 |
Pages |
144114-144114,8 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
Using an effective one-dimensional cluster expansion in combination with first-principles electronic structure calculations we have studied the energetics and electronic properties of Sb-Te layered systems. For a Te concentration between 0 and 60 at. % an almost continuous series of metastable structures is obtained consisting of consecutive Sb bilayers next to consecutive Sb2Te3 units, with the general formula (Sb-2)(n)(Sb2Te3)(m) (n, m = 1,2, ... ). Between 60 and 100 at.% no stable structures are found. We account explicitly for the weak van derWaals bonding between Sb bilayers and Sb2Te3 units by using a recently developed functional, which strongly improves the interlayer bonding distances. At T = 0 K, no evidence is found for the existence of two separate single-phase regions delta and gamma and a two-phase region delta + gamma. Metastable compounds with a Te concentration between 0 and 40 at. % are semimetallic, whereas compounds with a Te concentration between 50 and 60 at. % are semiconducting. Compounds with an odd number of Sb layers are metallic and have a much higher formation energy than those with an even number of consecutive Sb layers, thereby favoring the formation of Sb bilayers. |
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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 |
000303115400004 |
Publication Date |
2012-04-23 |
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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 |
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 |
14 |
Open Access |
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Notes |
Iwt; Fwo |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:98255 |
Serial |
3129 |
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Permanent link to this record |
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Author |
Ludu, A.; Milošević, M.V.; Peeters, F.M. |
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Title |
Vortex states in axially symmetric superconductors in applied magnetic field |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Sn – 0378-4754 |
Abbreviated Journal |
Math Comput Simulat |
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Volume |
82 |
Issue |
7 |
Pages |
1258-1270 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We solve analytically the linearized Ginzburg-Landau (GL) equation in the presence of an uniform magnetic field with cylindrical boundary conditions. The solution of the non-linear GL equation is provided as an expansion in the basis of linearized solutions. We present examples of the resulting vortex structure for a solid and perforated superconducting cylinder. (C) 2012 IMACS. Published by Elsevier B.V. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000303097000009 |
Publication Date |
2012-02-11 |
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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 |
0378-4754; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.218 |
Times cited |
1 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 1.218; 2012 IF: 0.836 |
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Call Number |
UA @ lucian @ c:irua:98300 |
Serial |
3887 |
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Permanent link to this record |
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Author |
Shakouri, K.; Szafran, B.; Esmaeilzadeh, M.; Peeters, F.M. |
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Title |
Effective spin-orbit interaction Hamiltonian for quasi-one-dimensional quantum rings |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
16 |
Pages |
165314-165314,8 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The effective Hamiltonian for an electron in a quasi-one-dimensional quantum ring in the presence of spin-orbit interactions is derived. We demonstrate that, when both coupling types are simultaneously present, the effective Hamiltonian derived by the lowest-radial-state approximation produces energy spectra and charge densities which deviate strongly from the exact ones. For equal Rashba and Dresselhaus coupling constants the lowest-radial-state approximation opens artifactal avoided crossings in the energy spectra and deforms the circular symmetry of the confined charge densities. In this case, there does not exist a ring thin enough to justify the restriction to the lowest radially quantized energy state. We derive the effective Hamiltonian accounting for both the lowest and the first excited radial states, and show that the inclusion of the latter restores the correct features of the exact solution. Relation of this result to the states of a quantum wire is also discussed. |
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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 |
000303068800006 |
Publication Date |
2012-04-20 |
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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 |
32 |
Open Access |
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Notes |
; This work was partially supported by Polish Ministry of Science and Higher Education and its grants for Scientific Research. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:98258 |
Serial |
855 |
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Permanent link to this record |
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Author |
Pham, A.-T.; Sorée, B.; Magnus, W.; Jungemann, C.; Meinerzhagen, B.; Pourtois, G. |
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Title |
Quantum simulations of electrostatics in Si cylindrical junctionless nanowire nFETs and pFETs with a homogeneous channel including strain and arbitrary crystallographic orientations |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Solid state electronics |
Abbreviated Journal |
Solid State Electron |
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Volume |
71 |
Issue |
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Pages |
30-36 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Simulation results of electrostatics in Si cylindrical junctionless nanowire transistors with a homogenous channel are presented. Junctionless transistors including strain and arbitrary crystallographic orientations are studied. Size quantization effects are simulated by self-consistent solutions of the Poisson and Schrodinger equations. The 6 x 6 k.p method is employed for the calculation of the valence subband structure in a junctionless nanowire pFET. The influence of stress/strain and crystallographic channel orientation on to the electrostatics in terms of subband structure, charge density, and C-V curve is systematically studied. (C) 2011 Elsevier Ltd. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000303033800007 |
Publication Date |
2011-12-01 |
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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 |
0038-1101; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.58 |
Times cited |
2 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 1.58; 2012 IF: 1.482 |
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Call Number |
UA @ lucian @ c:irua:98245 |
Serial |
2786 |
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Permanent link to this record |
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Author |
Clem, J.R.; Mawatari, Y.; Berdiyorov, G.R.; Peeters, F.M. |
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Title |
Predicted field-dependent increase of critical currents in asymmetric superconducting nanocircuits |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
14 |
Pages |
144511-144511,16 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The critical current of a thin superconducting strip of width W much larger than the Ginzburg-Landau coherence length xi but much smaller than the Pearl length Lambda = 2 lambda(2)/d is maximized when the strip is straight with defect-free edges. When a perpendicular magnetic field is applied to a long straight strip, the critical current initially decreases linearly with H but then decreases more slowly with H when vortices or antivortices are forced into the strip. However, in a superconducting strip containing sharp 90 degrees or 180 degrees turns, the zero-field critical current at H = 0 is reduced because vortices or antivortices are preferentially nucleated at the inner corners of the turns, where current crowding occurs. Using both analytic London-model calculations and time-dependent Ginzburg-Landau simulations, we predict that in such asymmetric strips the resulting critical current can be increased by applying a perpendicular magnetic field that induces a current-density contribution opposing the applied current density at the inner corners. This effect should apply to all turns that bend in the same direction. |
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Place of Publication |
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Editor |
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Language |
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Wos |
000302611100004 |
Publication Date |
2012-04-10 |
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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 |
40 |
Open Access |
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Notes |
; This research, supported in part by the US Department of Energy, Office of Basic Energy Science, Division of Materials Sciences and Engineering, was performed in part at the Ames Laboratory, which is operated for the US Department of Energy by Iowa State University under Contract No. DE-AC02-07CH11358. This work also was supported in part by the Flemish Science Foundation (FWO-Vlaanderen) and the Belgian Science Policy (IAP). G.R.B. acknowledges individual support from FWO-Vlaanderen. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:98263 |
Serial |
2695 |
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Permanent link to this record |
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Author |
Saniz, R.; Partoens, B.; Peeters, F.M. |
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Title |
Green function approach to superconductivity in nanowires |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
14 |
Pages |
144504-144504,7 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Superconductivity in nanowires made of weak coupling superconductor materials is investigated using a Green function approach. We show that these are multigap systems in which the ratio Delta(T)/k(B)T(c) is to a large extent similar to what is observed in some high-T-c two-gap systems, such as MgB2 and some of the Fe-based superconductors. On the other hand, because of confinement, the superfluid density has a temperature behavior of the form n(s)(T) = 1 – (T/T-c)(3) near T-c, thus deviating from the BCS behavior for bulk superconductors. |
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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 |
000302290700006 |
Publication Date |
2012-04-03 |
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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 |
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 |
1 |
Open Access |
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Notes |
; This work was supported by FWO-Vl and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:97764 |
Serial |
1381 |
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Permanent link to this record |
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Author |
Kishore, V.V.R.; Čukarić, N.; Partoens, B.; Tadić, M.; Peeters, F.M. |
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Title |
Hole subbands in freestanding nanowires : six-band versus eight-band k.p modelling |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
24 |
Issue |
13 |
Pages |
135302-135302,10 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The electronic structure of GaAs, InAs and InSb nanowires is studied using the six-band and the eight-band k.p models. The effect of the different Luttinger-like parameters (in the eight-band model) on the hole band structure is investigated. Although GaAs nanostructures are often treated within a six-band model because of the large bandgap, it is shown that an eight-band model is necessary for a correct description of its hole spectrum. The camel-back structure usually found in the six-band model is not always present in the eight-band model. This camel-back structure depends on the interaction between light and heavy holes, especially the ones with opposite spin. The latter effect is less pronounced in an eight-band model, but could be very sensitive to the Kane inter-band energy (E-P) value. |
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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 |
000302120100007 |
Publication Date |
2012-03-06 |
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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 |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.649 |
Times cited |
13 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), Belgian Science Policy (IAP) and the Ministry of Education and Science of Serbia. ; |
Approved |
Most recent IF: 2.649; 2012 IF: 2.355 |
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Call Number |
UA @ lucian @ c:irua:97763 |
Serial |
1479 |
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Permanent link to this record |
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Author |
Lucena, D.; Tkachenko, D.V.; Nelissen, K.; Misko, V.R.; Ferreira, W.P.; Farias, G.A.; Peeters, F.M. |
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Title |
Transition from single-file to two-dimensional diffusion of interacting particles in a quasi-one-dimensional channel |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : E : statistical, nonlinear, and soft matter physics |
Abbreviated Journal |
Phys Rev E |
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Volume |
85 |
Issue |
3:1 |
Pages |
031147-031147,12 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Diffusive properties of a monodisperse system of interacting particles confined to a quasi-one-dimensional channel are studied using molecular dynamics simulations. We calculate numerically the mean-squared displacement (MSD) and investigate the influence of the width of the channel (or the strength of the confinement potential) on diffusion in finite-size channels of different shapes (i.e., straight and circular). The transition from single-file diffusion to the two-dimensional diffusion regime is investigated. This transition [ regarding the calculation of the scaling exponent (alpha) of the MSD <Delta x(2)(t)> proportional to t(alpha)] as a function of the width of the channel is shown to change depending on the channel's confinement profile. In particular, the transition can be either smooth (i.e., for a parabolic confinement potential) or rather sharp (i.e., for a hard-wall potential), as distinct from infinite channels where this transition is abrupt. This result can be explained by qualitatively different distributions of the particle density for the different confinement potentials. |
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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 |
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Wos |
000302117900003 |
Publication Date |
2012-03-29 |
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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 |
1539-3755;1550-2376; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.366 |
Times cited |
38 |
Open Access |
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Notes |
; This work was supported by CNPq, FUNCAP (Pronex grant), the “Odysseus” program of the Flemish Government, the Flemish Science Foundation (FWO-Vl), the bilateral program between Flanders and Brazil, and the collaborative program CNPq-FWO-Vl. ; |
Approved |
Most recent IF: 2.366; 2012 IF: 2.313 |
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Call Number |
UA @ lucian @ c:irua:97784 |
Serial |
3699 |
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Permanent link to this record |
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Author |
Neek-Amal, M.; Peeters, F.M. |
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Title |
Effect of grain boundary on the buckling of graphene nanoribbons |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
100 |
Issue |
10 |
Pages |
101905-101905,4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The buckling of graphene nano-ribbons containing a grain boundary is studied using atomistic simulations where free and supported boundary conditions are invoked. We consider the buckling transition of two kinds of grain boundaries with special symmetry. When graphene contains a large angle grain boundary with theta = 21.8 degrees, the buckling strains are larger than those of perfect graphene when the ribbons with free (supported) boundary condition are subjected to compressive tension parallel (perpendicular) to the grain boundary. This is opposite for the results of theta = 32.2 degrees. The shape of the deformations of the buckled graphene nanoribbons depends on the boundary conditions, the presence of the particular used grain boundaries, and the direction of applied in-plane compressive tension. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3692573] |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000301655500021 |
Publication Date |
2012-03-06 |
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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 |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
18 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; |
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
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Call Number |
UA @ lucian @ c:irua:97794 |
Serial |
809 |
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Permanent link to this record |
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Author |
Michel, K.H.; Verberck, B. |
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Title |
Theory of rigid-plane phonon modes in layered crystals |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
9 |
Pages |
094303-094303,11 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The lattice dynamics of low-frequency rigid-plane modes in metallic (graphene multilayers, GML) and in insulating (hexagonal boron-nitride multilayers, BNML) layered crystals is investigated. The frequencies of shearing and compression (stretching) modes depend on the layer number N and are presented in the form of fan diagrams. The results for GML and BNML are very similar. In both cases, only the interactions (van der Waals and Coulomb) between nearest-neighbor planes are effective, while the interactions between more distant planes are screened. A comparison with recent Raman scattering results on low-frequency shear modes in GML [Tan et al., Nat. Mater., in press, doi: 10.1038/nmat3245, (2012)] is made. Relations with the low-lying rigid-plane phonon dispersions in the bulk materials are established. Master curves, which connect the fan diagram frequencies for any given N, are derived. Static and dynamic thermal correlation functions for rigid-layer shear and compression modes are calculated. The results might be of use for the interpretation of friction force experiments on multilayer crystals. |
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Place of Publication |
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Editor |
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Language |
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Wos |
000301646000006 |
Publication Date |
2012-03-19 |
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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 |
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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 |
38 |
Open Access |
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Notes |
; The authors are indebted to J. Maultzsch for bringing Ref. 20 to their attention. They thank D. Lamoen, F.M. Peeters, B. Trauzettel, and C. Van Haesendonck for useful discussions. This work has been financially supported by the Research Foundation Flanders (FWO). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:97787 |
Serial |
3619 |
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Permanent link to this record |
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Author |
Kao, K.-H.; Verhulst, A.S.; Vandenberghe, W.G.; Sorée, B.; Groeseneken, G.; De Meyer, K. |
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Title |
Modeling the impact of junction angles in tunnel field-effect transistors |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Solid state electronics |
Abbreviated Journal |
Solid State Electron |
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Volume |
69 |
Issue |
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Pages |
31-37 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We develop an analytical model for a tunnel field-effect transistor (TFET) with a tilted source junction angle. The tunnel current is derived by using circular tunnel paths along the electric field. The analytical model predicts that a smaller junction angle improves the TFET performance, which is supported by device simulations. An analysis is also made based on straight tunnel paths and tunnel paths corresponding to the trajectory of a classical particle. In all the aforementioned cases, the same conclusions are obtained. A TFET configuration with an encroaching polygon source junction is studied to analyze the junction angle dependence at the smallest junction angles. The improvement of the subthreshold swing (SS) with decreasing junction angle can be achieved by using thinner effective oxide thickness, smaller band gap material and longer encroaching length of the encroaching junction. A TFET with a smaller junction angle on the source side also has an innate immunity against the degradation of the fringing field from the gate electrode via a high-k spacer. A large junction angle on the drain side can suppress the unwanted ambipolar current of TFETs. (c) 2011 Elsevier Ltd. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000301561600009 |
Publication Date |
2012-01-16 |
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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 |
0038-1101; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.58 |
Times cited |
9 |
Open Access |
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Notes |
; We acknowledge the input on nanowire processing of Rita Rooyackers and useful discussions with Wim Magnus. William Vandenberghe gratefully acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). This work was also supported by imec's Industrial Affiliation Program. ; |
Approved |
Most recent IF: 1.58; 2012 IF: 1.482 |
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Call Number |
UA @ lucian @ c:irua:97816 |
Serial |
2145 |
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Permanent link to this record |
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Author |
Berdiyorov, G.R.; Hernández-Nieves, A.D.; Milošević, M.V.; Peeters, F.M.; Dominguez, D. |
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Title |
Flux-quantum-discretized dynamics of magnetic flux entry, exit, and annihilation in current-driven mesoscopic type-I superconductors |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
85 |
Issue |
9 |
Pages |
092502-092502,4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We study nonlinear flux dynamics in a current-carrying type-I superconductor. The stray magnetic field of the current induces the intermediate state, where nucleation of flux domains is discretized to a single fluxoid at a time, while their final shape (tubular or laminar), size, and nucleation rate depend on applied current and edge conditions. The current induces opposite flux domains on opposite sides of the sample, and subsequently drives them to annihilation-which is also discretized, as a sequence of vortex-antivortex pairs. The discretization of both nucleation and annihilation leaves measurable traces in the voltage across the sample and in locally probed magnetization. The reported dynamic phenomena thus provide an unambiguous proof of a flux quantum being the smallest building block of the intermediate state in type-I superconductors. |
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Corporate Author |
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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 |
000301183000002 |
Publication Date |
2012-03-07 |
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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 |
14 |
Open Access |
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Notes |
; This work was supported by the Belgian Science Policy (IAP), the Flemish Science Foundation (FWO-Vl), and the collaborative project FWO-MINCyT (Project No. FW/08/01). G. R. B. and A. D. H acknowledge support from FWO-Vl. A. D. H. and D. D. acknowledge support from CONICET, CNEA, and ANPCyT (Grant No. PICT07-824). ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
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Call Number |
UA @ lucian @ c:irua:97180 |
Serial |
1243 |
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Permanent link to this record |