| Records |
| Author |
Li, Z.; Covaci, L.; Marsiglio, F. |
| Title |
Impact of Dresselhaus versus Rashba spin-orbit coupling on the Holstein polaron |
Type |
A1 Journal article |
Year  |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
85 |
Issue |
20 |
Pages |
205112-205112,5 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| 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. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000303794900003 |
Publication Date |
2012-05-09 |
| 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 |
|
Edition |
|
| 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 |
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 |
| Call Number |
UA @ lucian @ c:irua:99121 |
Serial |
1558 |
| Permanent link to this record |
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| Author |
Li, Z.; Covaci, L.; Berciu, M.; Baillie, D.; Marsiglio, F. |
| Title |
Impact of spin-orbit coupling on the Holstein polaron |
Type |
A1 Journal article |
| Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
83 |
Issue |
19 |
Pages |
195104-195104,9 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We utilize an exact variational numerical procedure to calculate the ground state properties of a polaron in the presence of a Rashba-like spin-orbit interaction. Our results corroborate previous work performed with the momentum average approximation and with weak-coupling perturbation theory. We find that spin-orbit coupling increases the effective mass in the regime with weak electron-phonon coupling, and decreases the effective mass in the regimes of intermediate and strong electron-phonon coupling. Analytical strong-coupling perturbation theory results confirm our numerical results in the small-polaron regime. A large amount of spin-orbit coupling can lead to a significant lowering of the polaron effective mass. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000290162500001 |
Publication Date |
2011-05-03 |
| 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 |
|
Edition |
|
| ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
9 |
Open Access |
|
| Notes |
; This work was supported in part by the Natural Sciences and Engineering Research Council of Canada (NSERC), by ICORE (Alberta), by Alberta Ingenuity, by the Flemish Science Foundation (FWO-Vl), and by the Canadian Institute for Advanced Research (CIfAR). ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
| Call Number |
UA @ lucian @ c:irua:89718 |
Serial |
1561 |
| Permanent link to this record |
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| 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 |
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Editor |
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| Language |
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Wos |
000270383100077 |
Publication Date |
2009-09-25 |
| 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 |
1098-0121 |
ISBN |
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Additional Links |
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| Impact Factor |
3.836 |
Times cited |
|
Open Access |
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| Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
| Call Number |
UA @ lucian @ |
Serial |
4436 |
| Permanent link to this record |
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| Author |
Kim, W.; Covaci, L.; Dogan, F.; Marsiglio, F. |
| Title |
Quantum mechanics of spin transfer in coupled electron-spin chains |
Type |
A1 Journal article |
| Year |
2007 |
Publication |
Epl |
Abbreviated Journal |
Epl-Europhys Lett |
| Volume |
79 |
Issue |
6 |
Pages |
67004 |
| Keywords |
A1 Journal article |
| Abstract |
The manner in which spin-polarized electrons interact with a magnetized thin film is currently described by a semi-classical approach. This in turn provides our present understanding of the spin transfer, or spin torque phenomenon. However, spin is an intrinsically quantum-mechanical quantity. Here, we make the first strides towards a fully quantum-mechanical description of spin transfer through spin currents interacting with a Heisenberg-coupled spin chain. Because of quantum entanglement, this requires a formalism based on the density matrix approach. Our description illustrates how individual spins in the chain time-evolve as a result of spin transfer. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000250409500023 |
Publication Date |
2007-08-24 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0295-5075 |
ISBN |
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Additional Links |
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| Impact Factor |
1.957 |
Times cited |
3 |
Open Access |
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| Notes |
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Approved |
Most recent IF: 1.957; 2007 IF: 2.206 |
| Call Number |
UA @ lucian @ |
Serial |
4430 |
| Permanent link to this record |
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| Author |
Kim, W.; Covaci, L.; Marsiglio, F. |
| Title |
Impurity scattering of wave packets on a lattice |
Type |
A1 Journal article |
| Year |
2006 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
74 |
Issue |
20 |
Pages |
205120 |
| Keywords |
A1 Journal article |
| Abstract |
Quantum transport in a lattice is distinct from its counterpart in continuum media. Even a free wave packet travels differently in a lattice than in the continuum. We describe quantum scattering in a one-dimensional lattice and illustrate characteristics of quantum transport such as resonant transmission. In particular we examine the transport characteristics of a random trimer model. We demonstrate the real-time propagation of a wave packet and its phase shift due to impurity configurations. Spin-flip scattering is also taken into account in a spin-chain system. We show how individual spins in the chain evolve as a result of a spin-flip interaction between an incoming electron and a spin chain. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000242409400030 |
Publication Date |
2006-11-27 |
| 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 |
ISBN |
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Additional Links |
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| Impact Factor |
3.836 |
Times cited |
14 |
Open Access |
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| Notes |
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Approved |
Most recent IF: 3.836; 2006 IF: 3.107 |
| Call Number |
UA @ lucian @ |
Serial |
4428 |
| Permanent link to this record |
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| |
| Author |
Kim, W.; Covaci, L.; Marsiglio, F. |
| Title |
Hidden symmetries of electronic transport in a disordered one-dimensional lattice |
Type |
A1 Journal article |
| Year |
2006 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
73 |
Issue |
19 |
Pages |
195109 |
| Keywords |
A1 Journal article |
| Abstract |
Correlated, or extended, impurities play an important role in the transport properties of dirty metals. Here, we examine, in the framework of a tight-binding lattice, the transmission of a single electron through an array of correlated impurities. In particular we show that particles transmit through an impurity array in identical fashion, regardless of the direction of traversal. The demonstration of this fact is straightforward in the continuum limit, but requires a detailed proof for the discrete lattice. We also briefly demonstrate and discuss the time evolution of these scattering states, to delineate regions (in time and space) where the aforementioned symmetry is violated. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000237950400042 |
Publication Date |
2006-05-11 |
| 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 |
ISBN |
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Additional Links |
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| Impact Factor |
3.836 |
Times cited |
5 |
Open Access |
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| Notes |
|
Approved |
Most recent IF: 3.836; 2006 IF: 3.107 |
| Call Number |
UA @ lucian @ |
Serial |
4429 |
| Permanent link to this record |
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| Author |
Covaci, L.; Marsiglio, F. |
| Title |
Proximity effect and Josephson current in clean strong/weak/strong superconducting trilayers |
Type |
A1 Journal article |
| Year |
2006 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
73 |
Issue |
1 |
Pages |
014503 |
| Keywords |
A1 Journal article |
| Abstract |
Recent measurements of the Josephson critical current through LSCO/LCO/LSCO thin films showed an unusually large proximity effect. Using the Bogoliubov-de Gennes equations for a tight-binding Hamiltonian we describe the proximity effect in weak links between a superconductor with critical temperature T-c and one with critical temperature T-c('), where T-c > T-c('). The weak link (N-') is therefore a superconductor above its own critical temperature and the superconducting regions are considered to have either s-wave or d-wave symmetry. We note that the proximity effect is enhanced due to the presence of superconducting correlations in the weak link. The dc Josephson current is calculated, and we obtain a nonzero value for temperatures greater than T-c(') for sizes of the weak links that can be almost an order of magnitude greater than the conventional coherence length. Considering pockets of superconductivity in the N-' layer, we show that this can lead to an even larger effect on the Josephson critical current by effectively shortening the weak link. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000235009000103 |
Publication Date |
2006-01-03 |
| 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 |
ISBN |
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Additional Links |
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| Impact Factor |
3.836 |
Times cited |
31 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.836; 2006 IF: 3.107 |
| Call Number |
UA @ lucian @ |
Serial |
4427 |
| Permanent link to this record |
