Records |
Author |
Li, B.; Partoens, B.; Peeters, F.M.; Magnus, W. |
Title |
Dielectric mismatch effect on coupled shallow impurity states in a semiconductor nanowire |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
8 |
Pages |
085306,1-085306,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Coupled shallow impurity states in a freestanding semiconductor nanowire and in a semiconductor nanowire surrounded by a metallic gate are studied within the effective-mass approximation. Bonding and antibonding states are found due to the coupling of the two impurities, and their energy converges with increasing distance di between the two impurities. The dependences of the binding energy on the wire radius R, the distance di between the two impurities, and the impurity radial position in the nanowire are examined. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000263816000051 |
Publication Date |
2009-02-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:76223 |
Serial |
691 |
Permanent link to this record |
|
|
|
Author |
Pourghaderi, M.A.; Magnus, W.; Sorée, B.; Meuris, M.; de Meyer, K.; Heyns, M. |
Title |
Tunneling-lifetime model for metal-oxide-semiconductor structures |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
8 |
Pages |
085315,1-085315,10 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In this paper we investigate the basic physics of charge carriers (electrons) leaking out of the inversion layer of a metal-oxide-semiconductor capacitor with a biased gate. In particular, we treat the gate leakage current as resulting from two combined processes: (1) the time-dependent decay of electron wave packets representing the inversion-layer charge and (2) the local generation of new electrons replacing those that have leaked away. As a result, the gate current simply emerges as the ratio of the total charge in the inversion layer to the tunneling lifetime. The latter is extracted from the quantum dynamics of the decaying wave packets, while the generation rate is incorporated as a phenomenological source term in the continuity equation. Not only do the gate currents calculated with this model agree very well with experiment, the model also provides an onset to solve the paradox of the current-free bound states representing the resonances of the Schrödinger equation that governs the fully coupled metal-oxide-semiconductor system. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000269639300076 |
Publication Date |
2009-08-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
2 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:78294 |
Serial |
3763 |
Permanent link to this record |
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|
|
Author |
Masir, M.R.; Vasilopoulos, P.; Peeters, F.M. |
Title |
Magnetic Kronig-Penney model for Dirac electrons in single-layer graphene |
Type |
A1 Journal article |
Year |
2009 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
11 |
Issue |
|
Pages |
095009,1-095009,21 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
he properties of Dirac electrons in a magnetic superlattice (SL) on graphene consisting of very high and thin (δ-function) barriers are investigated. We obtain the energy spectrum analytically and study the transmission through a finite number of barriers. The results are contrasted with those for electrons described by the Schrödinger equation. In addition, a collimation of an incident beam of electrons is obtained along the direction perpendicular to that of the SL. We also highlight an analogy with optical media in which the refractive index varies in space. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000270513500008 |
Publication Date |
2009-10-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.786 |
Times cited |
89 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2009 IF: 3.312 |
Call Number |
UA @ lucian @ c:irua:79241 |
Serial |
1884 |
Permanent link to this record |
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|
|
Author |
Tinck, S.; Boullart, W.; Bogaerts, A. |
Title |
Investigation of etching and deposition processes of Cl2/O2/Ar inductively coupled plasmas on silicon by means of plasmasurface simulations and experiments |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
Volume |
42 |
Issue |
|
Pages |
095204,1-095204,13 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In this paper, a simulation method is described to predict the etching behaviour of Cl2/O2/Ar inductively coupled plasmas on a Si substrate, as used in shallow trench isolation for the production of electronic devices. The hybrid plasma equipment model (HPEM) developed by Kushner et al is applied to calculate the plasma characteristics in the reactor chamber and two additional Monte Carlo simulations are performed to predict the fluxes, angles and energy of the plasma species bombarding the Si substrate, as well as the resulting surface processes such as etching and deposition. The simulations are performed for a wide variety of operating conditions such as gas composition, chamber pressure, power deposition and substrate bias. It is predicted by the simulations that when the fraction of oxygen in the gas mixture is too high, the oxidation of the Si substrate is superior to the etching of Si by chlorine species, resulting in an etch rate close to zero as is also observed in the experiments. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000265531000030 |
Publication Date |
2009-04-16 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-3727;1361-6463; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.588 |
Times cited |
23 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.588; 2009 IF: 2.083 |
Call Number |
UA @ lucian @ c:irua:75601 |
Serial |
1731 |
Permanent link to this record |
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|
|
Author |
Bultinck, E.; Bogaerts, A. |
Title |
Particle-in-cell/Monte Carlo collisions treatment of an Ar/O2 magnetron discharge used for the reactive sputter deposition of TiOx films |
Type |
A1 Journal article |
Year |
2009 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
11 |
Issue |
|
Pages |
103010-103010,24 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The physical processes in an Ar/O2 magnetron discharge used for the reactive sputter deposition of TiOx thin films were simulated with a 2d3v particle-in-cell/Monte Carlo collisions (PIC/MCC) model. The plasma species taken into account are electrons, Ar+ ions, fast Arf atoms, metastable Arm* atoms, Ti+ ions, Ti atoms, O+ ions, O2+ ions, O− ions and O atoms. This model accounts for plasmatarget interactions, such as secondary electron emission and target sputtering, and the effects of target poisoning. Furthermore, the deposition process is described by an analytical surface model. The influence of the O2/Ar gas ratio on the plasma potential and on the species densities and fluxes is investigated. Among others, it is shown that a higher O2 pressure causes the region of positive plasma potential and the O− density to be more spread, and the latter to decrease. On the other hand, the deposition rates of Ti and O are not much affected by the O2/Ar proportion. Indeed, the predicted stoichiometry of the deposited TiOx film approaches x=2 for nearly all the investigated O2/Ar proportions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000270820900001 |
Publication Date |
2009-10-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.786 |
Times cited |
24 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2009 IF: 3.312 |
Call Number |
UA @ lucian @ c:irua:78326 |
Serial |
2559 |
Permanent link to this record |
|
|
|
Author |
Doğan, F.; Covaci, L.; Kim, W.; Marsiglio, F. |
Title |
Emerging nonequilibrium bound state in spin-current–local-spin scattering |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
10 |
Pages |
104434 |
Keywords |
A1 Journal article |
Abstract |
Magnetization reversal is a well-studied problem with obvious applicability in computer hard drives. One can accomplish a magnetization reversal in at least one of two ways: application of a magnetic field or through a spin current. The latter is more amenable to a fully quantum-mechanical analysis. We formulate and solve the problem whereby a spin current interacts with a ferromagnetic Heisenberg spin chain, to eventually reverse the magnetization of the chain. Spin flips are accomplished through both elastic and inelastic scattering. A consequence of the inelastic-scattering channel, when it is no longer energetically possible, is the occurrence of a nonequilibrium bound state, which is an emergent property of the coupled local plus itinerant spin system. For certain definite parameter values the itinerant spin lingers near the local spins for some time, before eventually leaking out as an outwardly diffusing state. This phenomenon results in spin-flip dynamics and filtering properties for this type of system. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
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Language |
|
Wos |
000270383100077 |
Publication Date |
2009-09-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121 |
ISBN |
|
Additional Links |
|
Impact Factor |
3.836 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ |
Serial |
4436 |
Permanent link to this record |
|
|
|
Author |
Nguten, N.T.T.; Peeters, F.M. |
Title |
Many-body effects in the cyclotron resonance of a magnetic dot |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
11 |
Pages |
115335,1-115335,9 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Intraband cyclotron resonance (CR) transitions of a two-electron quantum dot containing a single magnetic ion is investigated for different Coulomb interaction strengths and different positions of the magnetic ion. In contrast to the usual parabolic quantum dots where CR is independent of the number of electrons, we found here that due to the presence of the magnetic ion Kohn's theorem no longer holds and CR is different for systems with different number of electrons and different effective electron-electron Coulomb interaction strength. Many-body effects result in shifts in the transition energies and change the number of CR lines. The position of the magnetic ion inside the quantum dot affects the structure of the CR spectrum by changing the position and the number of crossings and anticrossings in the transition energies and oscillator strengths. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000270383200110 |
Publication Date |
2009-09-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
6 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:79228 |
Serial |
1941 |
Permanent link to this record |
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|
|
Author |
Martens, T.; Brok, W.J.M.; van Dijk, J.; Bogaerts, A. |
Title |
On the regime transitions during the formation of an atmospheric pressure dielectric barrier glow discharge |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
Volume |
42 |
Issue |
12 |
Pages |
122002,1-122002,5 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The atmospheric pressure dielectric barrier discharge in helium is a pulsed discharge in nature. If during the electrical current pulse a glow discharge is reached, then this pulse will last only a few microseconds in operating periods of sinusoidal voltage with lengths of about 10 to 100 µs. In this paper we demonstrate that right before a glow discharge is reached, the discharge very closely resembles the commonly assumed Townsend discharge structure, but actually contains some significant differing features and hence should not be considered as a Townsend discharge. In order to clarify this, we present calculation results of high time and space resolution of the pulse formation. The results indicate that indeed a maximum of ionization is formed at the anode, but that the level of ionization remains high and that the electric field at that time is significantly disturbed. Our results also show where this intermediate structure comes from. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000266639300002 |
Publication Date |
2009-05-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-3727;1361-6463; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.588 |
Times cited |
21 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.588; 2009 IF: 2.083 |
Call Number |
UA @ lucian @ c:irua:76458 |
Serial |
2450 |
Permanent link to this record |
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|
|
Author |
Peelaers, H.; Partoens, B.; Peeters, F.M. |
Title |
Phonons in Ge nanowires |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
95 |
Issue |
12 |
Pages |
122110,1-122110,3 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The phonon spectra of thin freestanding, hydrogen passivated, Ge nanowires are calculated by ab initio techniques. The effect of confinement on the phonon modes as caused by the small diameters of the wires is investigated. Confinement causes a hardening of the optical modes and a softening of the longitudinal acoustic modes. The stability of the nanowires, undoped or doped with B or P atoms, is investigated using the obtained phonon spectra. All considered wires were stable, except for highly doped, very thin nanowires. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000270243800035 |
Publication Date |
2009-09-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
12 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.411; 2009 IF: 3.554 |
Call Number |
UA @ lucian @ c:irua:79307 |
Serial |
2606 |
Permanent link to this record |
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|
|
Author |
Neyts, E.; Eckert, M.; Mao, M.; Bogaerts, A. |
Title |
Numerical simulation of hydrocarbon plasmas for nanoparticle formation and the growth of nanostructured thin films |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Plasma physics and controlled fusion |
Abbreviated Journal |
Plasma Phys Contr F |
Volume |
51 |
Issue |
|
Pages |
124034,1-124034,8 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
This paper outlines two different numerical simulation approaches, carried out by our group, used for describing hydrocarbon plasmas in their applications for either nanoparticle formation in the plasma or the growth of nanostructured thin films, such as nanocrystalline diamond (NCD). A plasma model based on the fluid approach is utilized to study the initial mechanisms giving rise to nanoparticle formation in an acetylene plasma. The growth of NCD is investigated by molecular dynamics simulations, describing the interaction of the hydrocarbon species with a substrate. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
Language |
|
Wos |
000271940800045 |
Publication Date |
2009-11-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0741-3335;1361-6587; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.392 |
Times cited |
2 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.392; 2009 IF: 2.409 |
Call Number |
UA @ lucian @ c:irua:79132 |
Serial |
2405 |
Permanent link to this record |
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|
|
Author |
Földi, P.; Kálmán, O.; Peeters, F.M. |
Title |
Stability of spintronic devices based on quantum ring networks |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
12 |
Pages |
125324,1-125324,9 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Transport properties in mesoscopic networks are investigated, where the strength of the (Rashba-type) spin-orbit coupling is tuned with external gate voltages. We analyze in detail to what extent the ideal behavior and functionality of some promising network-based devices are modified by random (spin-dependent) scattering events and by thermal fluctuations. It is found that although the functionality of these devices is obviously based on the quantum coherence of the transmitted electrons, there is a certain stability: moderate level of errors can be tolerated. For mesoscopic networks made of typical semiconductor materials, we found that when the energy distribution of the input carriers is narrow enough, the devices can operate close to their ideal limits even at relatively high temperature. As an example, we present results for two different networks: one that realizes a Stern-Gerlach device and another that simulates a spin quantum walker. Finally we propose a simple network that can act as a narrow band energy filter even in the presence of random scatterers. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000270383300091 |
Publication Date |
2009-09-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
41 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:79230 |
Serial |
3131 |
Permanent link to this record |
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|
|
Author |
Chaves, A.; Farias, G.A.; Peeters, F.M.; Szafran, B. |
Title |
Wave packet dynamics in semiconductor quantum rings of finite width |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
12 |
Pages |
125331,1-125331,14 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The time evolution of a wave packet injected into a semiconductor quantum ring is investigated in order to obtain the transmission and reflection probabilities. Within the effective-mass approximation, the time-dependent Schrödinger equation is solved for a system with nonzero width of the ring and leads and finite potential-barrier heights, where we include smooth lead-ring connections. In the absence of a magnetic field, an analysis of the projection of the wave function over the different subband states shows that when the injected wave packet is within a single subband, the junction can scatter this wave packet into different subbands but remarkably at the second junction the wave packet is scattered back into the subband state of the incoming wave packet. If a magnetic field is applied perpendicularly to the ring plane, transmission and reflection probabilities exhibit Aharonov-Bohm (AB) oscillations and the outgoing electrons may end up in different subband states from those of the incoming electrons. Localized impurities, placed in the ring arms, influence the AB oscillation period and amplitude. For a single impurity or potential barrier of sufficiently strong strength, the period of the AB oscillations is halved while for two impurities localized in diametrically opposite points of the ring, the original AB period is recovered. A theoretical investigation of the confined states and time evolution of wave packets in T wires is also made, where a comparison between this system and the lead-ring junction is drawn. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000270383300098 |
Publication Date |
2009-09-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
40 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:79231 |
Serial |
3906 |
Permanent link to this record |
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|
|
Author |
di Vece, M.; Bals, S.; Lievens, P.; Van Tendeloo, G. |
Title |
Compositional changes of Pd-Au bimetallic nanoclusters upon hydrogenation |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
12 |
Pages |
125420,1-125420,4 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Changes in the size distribution and composition of bimetallic Pd-Au nanoclusters have been observed after hydrogen exposure. This effect is caused by hydrogen-induced Ostwald ripening whereby the hydrogen reduces the binding energy of the cluster atoms leading to their detachment from the cluster. The composition changes due to a difference in mobility of the detached palladium and gold atoms on the surface. Fast palladium atoms contribute to the formation of larger nanoclusters, while the slower gold atoms are confined to the smaller nanoclusters. These transformations in the Pd-Au nanocluster size and composition set a limit for chemical reactions in which such nanoclusters are involved together with hydrogen. |
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000270383300121 |
Publication Date |
2009-09-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
28 |
Open Access |
|
Notes |
Fwo; Goa; Iap-Vi; Esteem 026019 |
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:79232 |
Serial |
445 |
Permanent link to this record |
|
|
|
Author |
Salje, E.K.H.; Zhang, H.; Idrissi, H.; Schryvers, D.; Carpenter, M.A.; Moya, X.; Planes, A. |
Title |
Mechanical resonance of the austenite/martensite interface and the pinning of the martensitic microstructures by dislocations in Cu74.08Al23.13Be2.79 |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review: B: condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
13 |
Pages |
134114,1-1134114,8 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
A single crystal of Cu74.08Al23.13Be2.79 undergoes a martensitic phase transition at 246 and 232 K under heating and cooling, respectively. The phase fronts between the austenite and martensite regions of the sample are weakly mobile with a power-law resonance under external stress fields. Surprisingly, the martensite phase is elastically much harder than the austenite phase showing that interfaces between various crystallographic variants are strongly pinned and cannot be moved by external stress while the phase boundary between the austenite and martensite regions in the sample remains mobile. This unusual behavior was studied by dynamical mechanical analysis (DMA) and resonant ultrasound spectroscopy. The remnant strain, storage modulus, and internal friction were recorded simultaneously for different applied forces in DMA. With increasing forces, the remnant strain increases monotonously while the internal friction peak height shows a minimum at 300 mN. Transmission electron microscopy shows that the pinning is generated by dislocations which are inherited from the austenite phase. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000271351300033 |
Publication Date |
2009-10-22 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
38 |
Open Access |
|
Notes |
Multimat |
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:78542 |
Serial |
1975 |
Permanent link to this record |
|
|
|
Author |
Moshnyaga, V.; Gehrke, K.; Sudheendra, L.; Belenchuk, A.; Raabe, S.; Shapoval, O.; Verbeeck, J.; Van Tendeloo, G.; Samwer, K. |
Title |
Electrical nonlinearity in colossal magnetoresistance manganite films: relevance of correlated polarons |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
13 |
Pages |
134413,1-134413,8 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The metal-insulator (MI) transition in epitaxial thin films of La0.75Ca0.25MnO3 (LCMO) is accompanied by the appearance of an intrinsic electrical nonlinearity. The latter, probed by electrical third harmonic voltage, U3, or resistance, R3=dU3/dJ, is drastically enhanced in the vicinity of the MI transition, TMI=267 K. Applied magnetic field, B=5 T, suppresses the nonlinearity, resulting in a huge nonlinear CMR3(TMI)~105%. R3 shows a peculiar low-frequency (1 kHz) dependence, R3~(-0)n, with exponent, n, changing across the MI transition from n~1,52 for TTMI to n=1 (T<TMI). The observed electrical nonlinearity in LCMO reflects the behavior of correlated polarons, the number of which dramatically enhances in the vicinity of TMI. We argued that correlated polarons, considered as electric-elastic quadrupoles, provide a nonlinear (quadratic) coupling to the electric field, yielding a third harmonic electric nonlinearity in LCMO. The reference film of La0.7Sr0.3MnO3 (LSMO), a prototypic double exchange system with second-order phase transition, is characterized as a linear metallic material in the whole range of temperatures (T=10400 K), magnetic fields (B=05 T), and frequencies (=11000 Hz). |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000265942800074 |
Publication Date |
2009-04-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
28 |
Open Access |
|
Notes |
Esteem 026019 |
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:77022UA @ admin @ c:irua:77022 |
Serial |
893 |
Permanent link to this record |
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|
|
Author |
Zha, G.-Q.; Milošević, M.V.; Zhou, S.-P.; Peeters, F.M. |
Title |
Magnetic flux periodicity in mesoscopic d-wave symmetric and asymmetric superconducting loops |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
14 |
Pages |
144501,1-144501,5 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The magnetic flux dependence of energy and supercurrent in mesoscopic d-wave symmetric and asymmetric superconducting loops is investigated by numerically solving the Bogoliubov-de Gennes equations self-consistently. For square loops, we find an hc/e-flux periodicity in energy and supercurrent and demonstrate that the flux periodicity is sensitive to the hole size and the superconducting pairing strength as well as temperature. The hc/2e-periodic behavior can be restored almost entirely when we displace the central hole sufficiently out of the center of the sample. In rectangular loops, the discrete current-carrying low-energy spectrum can exist for an odd winding number of the order parameter. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000271351500085 |
Publication Date |
2009-10-15 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
13 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:79994 |
Serial |
1879 |
Permanent link to this record |
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|
|
Author |
Tadić, M.; Peeters, F.M. |
Title |
Excitonic properties of strained triple quantum-ring molecules |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
15 |
Pages |
153305,1-153305,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The tunneling coupling in three vertically stacked (In,Ga)As/GaAs quantum rings is investigated. With increasing inter-ring separation (d), we find that the nonuniform strain results into a crossing of the lowest-energy electron states. Strain is also responsible for an increase in the ground electron energy above the level in the single quantum ring. The ground hole energy level exhibits decrease when d decreases, which is typical for antibonding states in an unstrained structure. These effects lead to a local maximum in the dependence of the ground-state exciton energy on d. Our theoretical results compare well with recent photoluminescence measurements but deviate considerably from the calculations for flat bands in quantum-ring molecules. We conclude that the nonuniform character of the strain distribution gives rise to a peculiar exciton hybridization in self-assembled quantum-ring molecules. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000265944200018 |
Publication Date |
2009-04-21 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
8 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:77024 |
Serial |
1123 |
Permanent link to this record |
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|
|
Author |
Li, J.; Chang, K.; Peeters, F.M. |
Title |
Dyakonov-Perel spin relaxation in InSb/AlxIn1-xSb quantum wells |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
15 |
Pages |
153307,1-153307,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate theoretically the Dyakonov-Perel spin relaxation time by solving the eight-band Kane model and Poisson equation self-consistently. Our results show distinct behavior with the single-band model due to the anomalous spin-orbit interactions in narrow band-gap semiconductors, and agree well with the experiment values reported in recent experiment [K. L. Litvinenko et al., New J. Phys. 8, 49 (2006)]. We find a strong resonant enhancement of the spin relaxation time appears for spin align along [11̅ 0] at a certain electron density at 4 K. This resonant peak is smeared out with increasing the temperature. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000271352000015 |
Publication Date |
2009-11-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
6 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:79996 |
Serial |
760 |
Permanent link to this record |
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|
|
Author |
Verberck, B.; Vliegenthart, G.A.; Gompper, G. |
Title |
Orientational ordering in solid C60 fullerene-cubane |
Type |
A1 Journal article |
Year |
2009 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
Volume |
130 |
Issue |
15 |
Pages |
154510,1-154510,14 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study the structure and phase behavior of fullerene-cubane C60·C8H8 by Monte Carlo simulation. Using a simple potential model capturing the icosahedral and cubic symmetries of its molecular constituents, we reproduce the experimentally observed phase transition from a cubic to an orthorhombic crystal lattice and the accompanying rotational freezing of the C60 molecules. We elaborate a scheme to identify the low-temperature orientations of individual molecules and to detect a pattern of orientational ordering similar to the arrangement of C60 molecules in solid C60. Our configuration of orientations supports a doubled periodicity along one of the crystal axes. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000265486300036 |
Publication Date |
2009-04-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-9606; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.965 |
Times cited |
8 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.965; 2009 IF: 3.093 |
Call Number |
UA @ lucian @ c:irua:77258 |
Serial |
2519 |
Permanent link to this record |
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|
|
Author |
Tomecka, D.M.; Kamieniarz, G.; Partoens, B.; Peeters, F.M. |
Title |
Ground state configurations and melting of two-dimensional non-uniformly charged classical clusters |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
21 |
Issue |
15 |
Pages |
155301,1-155301,7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We consider classical two-dimensional (2D) Coulomb clusters consisting of two species containing five particles with charge q1 and five with charge q2, respectively. Using Monte Carlo and molecular dynamics (MD) simulations, we investigated the ground state configurations as well as radial and angular displacements of particles as a function of temperature and their dependence on the ratio q = q2/q1. We found new configurations and a new multi-step melting behavior for q sufficiently different from the uniform charge limit q = 1. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000264708600007 |
Publication Date |
2009-03-18 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
2 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.649; 2009 IF: 1.964 |
Call Number |
UA @ lucian @ c:irua:76412 |
Serial |
1384 |
Permanent link to this record |
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|
Author |
Barbier, M.; Vasilopoulos, P.; Peeters, F.M.; Pereira, J.M. |
Title |
Bilayer graphene with single and multiple electrostatic barriers: band structure and transmission |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
15 |
Pages |
155402,1-155402,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We evaluate the electronic transmission and conductance in bilayer graphene through a finite number of potential barriers. Further, we evaluate the dispersion relation in a bilayer graphene superlattice with a periodic potential applied to both layers. As a model we use the tight-binding Hamiltonian in the continuum approximation. For zero bias the dispersion relation shows a finite gap for carriers with zero momentum in the direction parallel to the barriers. This is in contrast to single-layer graphene where no such gap was found. A gap also appears for a finite bias. Numerical results for the energy spectrum, conductance, and the density of states are presented and contrasted with those pertaining to single-layer graphene. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000265944200091 |
Publication Date |
2009-04-01 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
74 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:77025 |
Serial |
235 |
Permanent link to this record |
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|
Author |
Masir, M.R.; Matulis, A.; Peeters, F.M. |
Title |
Quasibound states of Schrödinger and Dirac electrons in a magnetic quantum dot |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
15 |
Pages |
155451,1-155451,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The properties of a two-dimensional electron are investigated in the presence of a circular step magnetic-field profile. Both electrons with parabolic dispersion as well as Dirac electrons with linear dispersion are studied. We found that in such a magnetic quantum dot no electrons can be confined. Nevertheless close to the Landau levels quasibound states can exist with a rather long lifetime. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000265944200140 |
Publication Date |
2009-04-30 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
55 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:77026 |
Serial |
2800 |
Permanent link to this record |
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|
|
Author |
Földi, P.; Benedict, M.G.; Kalman, O.; Peeters, F.M. |
Title |
Quantum rings with time-dependent spin-orbit coupling: Spintronic Rabi oscillations and conductance properties |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
16 |
Pages |
165303,1-165303,10 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The strength of the (Rashba-type) spin-orbit coupling in mesoscopic semiconductor rings can be tuned with external gate voltages. Here we consider the case of a periodically changing spin-orbit interaction strength in time as induced by sinusoidal voltages. In a closed one dimensional quantum ring with weak spin-orbit coupling, Rabi oscillations are shown to appear. We find that the time evolution of initially localized wave packets exhibits a series of collapse and revival phenomena. Partial revivalsthat are typical in nonlinear systemsare shown to correspond to superpositions of states localized at different spatial positions along the ring. These spintronic Schrödinger-cat states appear periodically, and similarly to their counterparts in other physical systems, they are found to be sensitive to disturbances caused by the environment. The time-dependent spin transport problem, when leads are attached to the ring, is also solved. We show that the sideband currents induced by the oscillating spin-orbit interaction strength can become the dominant output channel, even in the presence of moderate thermal fluctuations and random scattering events. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
|
Wos |
000271352100078 |
Publication Date |
2009-10-12 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
26 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:80002 |
Serial |
2784 |
Permanent link to this record |
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|
|
Author |
Berdiyorov, G.R.; Elmurodov, A.K.; Peeters, F.M.; Vodolazov, D.Y. |
Title |
Finite-size effect on the resistive state in a mesoscopic type-II superconducting stripe |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
17 |
Pages |
174506,1-174506,6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Within the time-dependent Ginzburg-Landau (TDGL) theory we studied the creation of phase-slip lines and the interplay with a vortex lattice in a finite-length superconducting thin stripe with finite-size normal metal leads. In zero magnetic field and with increasing transport current phase-slip lines appear across the sample leading to distinct jumps in the current-voltage characteristics. When a magnetic field is applied, the moving vortex lattice becomes rearranged by the external current and fast and slow moving vortex channels are formed. Curved vortex channels are observed near the normal contacts. We found the remarkable result that at small applied magnetic field the normal-state transition current is increased as compared to the one at zero magnetic field. This effect is more pronounced for larger values of the parameter in the TDGL formalism. This unusual field-induced increase in the critical current is a consequence of the nonuniform distribution of the current in the sample. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
Language |
|
Wos |
000266501100096 |
Publication Date |
2009-05-05 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
36 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:77398 |
Serial |
1196 |
Permanent link to this record |
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|
|
Author |
Geurts, R.; Milošević, M.V.; Peeters, F.M. |
Title |
Second generation of vortex-antivortex states in mesoscopic superconductors: stabilization by artificial pinning |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
79 |
Issue |
17 |
Pages |
174508,1-174508,5 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Antagonistic symmetries of superconducting polygons and their induced multivortex states in a homogeneous magnetic field may lead to the appearance of antivortices in the vicinity of the superconducting/normal-state boundary (where mesoscopic confinement is particularly strong). Resulting vortex-antivortex (V-Av) molecules match the sample symmetry but are extremely sensitive to defects and fluctuations and remain undetected experimentally. Here we show that V-Av states can reappear deep in the superconducting state due to an array of perforations in a polygonal setting, surrounding a central hole. Such states are no longer caused by the symmetry of the sample but rather by pinning itself, which prevents the vortex-antivortex annihilation. As a result, even micron size, clearly spaced V-Av molecules can be stabilized in large mesoscopic samples. |
Address |
|
Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000266501100098 |
Publication Date |
2009-05-06 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
17 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:77399 |
Serial |
2956 |
Permanent link to this record |
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|
|
Author |
Goodvin, G.L.; Covaci, L.; Berciu, M. |
Title |
Holstein polarons near surfaces |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys Rev Lett |
Volume |
103 |
Issue |
17 |
Pages |
176402 |
Keywords |
A1 Journal article |
Abstract |
We study the effects of a nearby surface on the spectral weight of a Holstein polaron, using the inhomogeneous momentum average approximation which is accurate over the entire range of electron-phonon (e-ph) coupling strengths. The broken translational symmetry is taken into account exactly. We find that the e-ph coupling gives rise to a large additional surface potential, with strong retardation effects, which may bind surface states even when they are not normally expected. The surface, therefore, has a significant effect and bulk properties are recovered only very far away from it. These results demonstrate that interpretation in terms of bulk quantities of spectroscopic data sensitive only to a few surface layers is not always appropriate. |
Address |
Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1 |
Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
|
Editor |
|
Language |
English |
Wos |
000271164500042 |
Publication Date |
2009-10-22 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0031-9007 |
ISBN |
|
Additional Links |
|
Impact Factor |
8.462 |
Times cited |
8 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 8.462; 2009 IF: 7.328 |
Call Number |
UA @ lucian @ |
Serial |
4435 |
Permanent link to this record |
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|
|
Author |
Karapetrov, G.; Milošević, M.V.; Iavarone, M.; Fedor, J.; Belkin, A.; Novosad, V.; Peeters, F.M. |
Title |
Transverse instabilities of multiple vortex chains in magnetically coupled NbSe2/permalloy superconductor/ferromagnet bilayers |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
80 |
Issue |
18 |
Pages |
180506,1-180506,4 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using scanning tunneling microscopy and Ginzburg-Landau simulations, we explore vortex configurations in magnetically coupled NbSe2/permalloy superconductor/ferromagnet bilayer. The permalloy film with stripe domain structure induces periodic local magnetic induction in the superconductor, creating a series of pinning-antipinning channels for externally added magnetic flux quanta. Such laterally confined Abrikosov vortices form quasi-one-dimensional arrays (chains). The transitions between multichain states occur through propagation of kinks at the intermediate fields. At high fields we show that the system becomes nonlinear due to a change in both the number of vortices and the confining potential. The longitudinal instabilities of the resulting vortex structures lead to vortices levitating in the antipinning channels. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000272310900031 |
Publication Date |
2009-11-18 |
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 |
Impact Factor |
3.836 |
Times cited |
38 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:80314 |
Serial |
3729 |
Permanent link to this record |
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Author |
Berdiyorov, G.R.; Milošević, M.V.; Peeters, F.M. |
Title |
Kinematic vortex-antivortex lines in strongly driven superconducting stripes |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
Volume |
19 |
Issue |
18 |
Pages |
184506,1-184506,8 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In the framework of the time-dependent Ginzburg-Landau formalism, we study the resistive state of a submicron superconducting stripe in the presence of a longitudinal current. Sufficiently strong current leads to phase slippage between the leads, which is manifested as oppositely charged kinematic vortices moving in opposite directions perpendicular to applied drive. Depending on the distribution of superconducting current density the vortex-antivortex either nucleate in the middle of the stripe and are expelled laterally or enter on opposite sides of the sample and are driven together to annihilation. We distinguish between the two scenarios as a function of relevant parameters and show how the creation/annihilation point of the vortex-antivortex and their individual velocity can be manipulated by applied magnetic field and current. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000266501200091 |
Publication Date |
2009-05-06 |
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 |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
75 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
Call Number |
UA @ lucian @ c:irua:77400 |
Serial |
1756 |
Permanent link to this record |
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Author |
Zelaya, E.; Tolley, A.; Condo, A.M.; Schumacher, G. |
Title |
Swift heavy ion irradiation of Cu-Zn-Al and Cu-Al-Ni alloys |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
21 |
Issue |
18 |
Pages |
185009-185009,8 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The effects produced by swift heavy ions in the martensitic (18R) and austenitic phase (beta) of Cu based shape memory alloys were characterized. Single crystal samples with a surface normal close to [210](18R) and [001](beta) were irradiated with 200 MeV of Kr(15+), 230 MeV of Xe(15+), 350 and 600 MeV of Au(26+) and Au(29+). Changes in the microstructure were studied with transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). It was found that swift heavy ion irradiation induced nanometer sized defects in the 18R martensitic phase. In contrast, a hexagonal close-packed phase formed on the irradiated surface of beta phase samples. HRTEM images of the nanometer sized defects observed in the 18R martensitic phase were compared with computer simulated images in order to interpret the origin of the observed contrast. The best agreement was obtained when the defects were assumed to consist of local composition modulations. |
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 |
000264934400014 |
Publication Date |
2009-03-25 |
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 |
Impact Factor |
2.649 |
Times cited |
8 |
Open Access |
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Notes |
|
Approved |
Most recent IF: 2.649; 2009 IF: 1.964 |
Call Number |
UA @ lucian @ c:irua:94551 |
Serial |
3399 |
Permanent link to this record |
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Author |
Covaci, L.; Berciu, M. |
Title |
Polaron formation in the presence of Rashba spin-orbit coupling: implications for spintronics |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys Rev Lett |
Volume |
102 |
Issue |
18 |
Pages |
186403 |
Keywords |
A1 Journal article |
Abstract |
We study the effects of the Rashba spin-orbit coupling on polaron formation, using a suitable generalization of the momentum average approximation. While previous work on a parabolic band model found that spin-orbit coupling increases the effective mass, we show that the opposite holds for a tight-binding model, unless both the spin-orbit and the electron-phonon couplings are weak. It is thus possible to lower the effective mass of the polaron by increasing the spin-orbit coupling. We also show that when the spin-orbit coupling is large as compared to the phonon energy, the polaron retains only one of the spin-polarized bands in its coherent spectrum. This has major implications for the propagation of spin-polarized currents in such materials, and thus for spintronic applications. |
Address |
Department of Physics, University of British Columbia, Vancouver, British Columbia, Canada, V6T 1Z1 |
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 |
English |
Wos |
000265948600049 |
Publication Date |
2009-05-08 |
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 |
ISBN |
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Additional Links |
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Impact Factor |
8.462 |
Times cited |
25 |
Open Access |
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Notes |
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Approved |
Most recent IF: 8.462; 2009 IF: 7.328 |
Call Number |
UA @ lucian @ |
Serial |
4434 |
Permanent link to this record |