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| Author | Shi, J.M.; Koenraad, P.M.; van de Stadt, A.F.W.; Peeters, F.M.; Devreese, J.T.; Wolter, J.H. | ||||
| Title | Electronic structure of a Si \delta-doped layer in a GaAs/AlxGa1-xAs/GaAs quantum barrier | Type | A1 Journal article | ||
| Year | 1996 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 54 | Issue | 11 | Pages | 7996-8004 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems | ||||
| Abstract | We present a theoretical study of the electronic structure of a heavily Si delta-doped layer in a GaAs/AlxGa1-xAs/GaAs quantum barrier. In this class of structures the effect of DX centers on the electronic properties can be tuned by changing the AlxGa1-xAs barrier width and/or the Al concentration, which leads to a lowering of the DX level with respect to the Fermi energy without disturbing the wave functions much. A self-consistent approach is developed in which the effective confinement potential and the Fermi energy of the system, the energies, the wave functions, and the electron densities of the discrete subbands have been obtained as a function of both the material parameters of the samples and the experimental conditions. The effect of DX centers on such structures at nonzero temperature and under an external pressure is investigated for three different models: (1) the DX(nc)(0) model with no correlation effects, (2) the d(+)/DX(0) model, and (3) the d(+)/DX(-) model with inclusion of correlation effects. In the actual calculation, influences of the background accepters, the discontinuity of the effective mass of the electrons at the interfaces of the different materials, band nonparabolicity, and the exchange-correlation energy of the electrons have been taken into account. We have found that (1) introducing a quantum barrier into delta-doped GaAs makes it possible to control the energy gaps between different electronic; subbands; (2) the electron wave functions are mon spread out when the repellent effect of the barriers is increased as compared to those in delta-doped GaAs; (3) increasing the quantum-barrier height and/or the application of hydrostatic pressure are helpful to experimentally observe the effect of the DX centers through a decrease of the total free-electron density; and (4) the correlation effects of the charged impurities are important for the systems under study. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | A1996VL14500066 | Publication Date | 2002-07-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0163-1829;1095-3795; | ISBN | Additional Links  |
UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.736 | Times cited | 11 | Open Access | |
| Notes | Approved | no | |||
| Call Number | UA @ lucian @ c:irua:104388 | Serial | 1012 | ||
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| Author | Verberck, B.; Nikolaev, A.V.; Michel, K.H. | ||||
| Title | Theoretical model for the structural phase transition at the metal-insulator transition in polymerized KC60 | Type | A1 Journal article | ||
| Year | 2002 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 66 | Issue | 16 | Pages | 165425-165425,14 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | The recently discovered structural transition in polymerized KC60 at about 50 K results in a doubling of the unit cell volume and accompanies the metal-insulator transition. Here we show that the ((a) over right arrow+(c) over right arrow,(b) over right arrow,(a) over right arrow-(c) over right arrow) superstructure results from small orientational charge density waves along the polymer chains and concomitant displacements of the surrounding K+ ions. The effect is specific for the space group Pmnn of KC60 and is absent in RbC60 and CsC60 (space group I2/m). The mechanism is relevant for the metal-insulator transition. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000179286400135 | Publication Date | 2002-10-30 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0163-1829;1095-3795; | ISBN | Additional Links |
UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 10 | Open Access | |
| Notes | Approved | Most recent IF: 3.836; 2002 IF: NA | |||
| Call Number | UA @ lucian @ c:irua:94907 | Serial | 3608 | ||
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| Author | Rosenauer, A.; Schowalter, M.; Glas, F.; Lamoen, D. | ||||
| Title | First-principles calculations of 002 structure factors for electron scattering in strained InxGa1-xAs | Type | A1 Journal article | ||
| Year | 2005 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 72 | Issue | 8 | Pages | 1-10 |
| Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
| Abstract | This work provides values of electron scattering 002 structure factors for InxGa1-xAs as a function of the In concentration x=0 to 1. These results allow accurate compositional analysis of pseudomorphically grown InxGa1-xAs/GaAs layers by transmission electron microscopy methods relying on the chemical sensitivity of the (002) beam. The calculations go beyond the limits of the isolated atom approximation, because they take into account charge redistribution effects between atomic sites in the crystal, strain, and static atomic displacements. The computations were performed by the full potential linearized augmented plane-wave method using a generalized gradient approximation for the exchange and correlation part of the potential. The calculations of strained InxGa1-xAs correspond to the strain state in specimens with large, small, and intermediate thickness in the electron beam direction. Additionally, the effect of static atomic displacements is taken into account. All results are listed in a parameterized form. The calculated 002 structure factor vanishes at an In concentration of 16.4%. This value is in a good agreement with previously reported experimental measurements. Hence, our results are a significant improvement with respect to the isolated atom approximation which is conventionally applied in transmission electron microscopy simulations, and which predicts a value of 22.5%. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000231564600106 | Publication Date | 2005-08-12 | |
| 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 | 42 | Open Access | |
| Notes | Approved | Most recent IF: 3.836; 2005 IF: 3.185 | |||
| Call Number | UA @ lucian @ c:irua:54918 | Serial | 1201 | ||
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| Author | Leys, F.E.; March, N.H.; Lamoen, D. | ||||
| Title | High pressure limiting forms of the zero-temperature equations of state of Ta and Pu from relativistic Thomas-Fermi theory | Type | A1 Journal article | ||
| Year | 2003 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 67 | Issue | Pages | 064109 | |
| Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000181501100021 | Publication Date | 2003-03-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0163-1829;1095-3795; | ISBN | Additional Links |
UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 1 | Open Access | |
| Notes | Approved | Most recent IF: 3.836; 2003 IF: NA | |||
| Call Number | UA @ lucian @ c:irua:45628 | Serial | 1439 | ||
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| Author | Leys, F.E.; March, N.H.; Angilella, G.G.N.; Lamoen, D. | ||||
| Title | Self consistent nonlocal linear-response theory of a relativistic electron gas | Type | A1 Journal article | ||
| Year | 2003 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 67 | Issue | Pages | 113105 | |
| Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000182035100005 | Publication Date | 2003-04-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0163-1829;1095-3795; | ISBN | Additional Links |
UA library record; WoS full record; | |
| Impact Factor | 3.836 | Times cited | Open Access | ||
| Notes | Approved | Most recent IF: 3.836; 2003 IF: NA | |||
| Call Number | UA @ lucian @ c:irua:45627 | Serial | 2973 | ||
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| Author | Misko, V.R.; Fomin, V.M.; Devreese, J.T. | ||||
| Title | Strong enhancement of superconductivity in a nanosized Pb bridge | Type | A1 Journal article | ||
| Year | 2001 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 64 | Issue | Pages | 014517,1-13 | |
| Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
| Abstract | |||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000169711900093 | Publication Date | 2002-07-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0163-1829;1095-3795; | ISBN | Additional Links |
UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 28 | Open Access | |
| Notes | Approved | Most recent IF: 3.836; 2001 IF: NA | |||
| Call Number | UA @ lucian @ c:irua:34316 | Serial | 3181 | ||
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| Author | Fomin, V.M.; Misko, V.R.; Devreese, J.T.; Moshchalkov, V.V. | ||||
| Title | Superconducting mesoscopic square loop | Type | A1 Journal article | ||
| Year | 1998 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
| Volume | 58 | Issue | Pages | 11703-11715 | |
| Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | 000076716700093 | Publication Date | 2002-07-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0163-1829;1095-3795; | ISBN | Additional Links |
UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 43 | Open Access | |
| Notes | Approved | Most recent IF: 3.836; 1998 IF: NA | |||
| Call Number | UA @ lucian @ c:irua:21906 | Serial | 3354 | ||
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| Author | Lamoen, D.; Ballone, P.; Parrinello, M. | ||||
| Title | Electronic structure, screening and charging effects at a metal/organic tunneling junction: a first principles study | Type | A1 Journal article | ||
| Year | 1996 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 54 | Issue | Pages | 5097 | |
| Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | A1996VE48800102 | Publication Date | 0000-00-00 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121; 0163-1829 | ISBN | Additional Links |
UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.736 | Times cited | 33 | Open Access | |
| Notes | Approved | PHYSICS, CONDENSED MATTER 16/67 Q1 # | |||
| Call Number | UA @ lucian @ c:irua:15820 | Serial | 1018 | ||
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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. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000235009000103 | Publication Date | 2006-01-03 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121 | ISBN | 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 | ||
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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. | ||||
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| Publisher | Place of Publication | Editor | |||
| 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 |
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| 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 | ||
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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. | ||||
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| Language | Wos | 000242409400030 | Publication Date | 2006-11-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121 | ISBN | Additional Links |
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| Impact Factor | 3.836 | Times cited | 14 | Open Access | |
| Notes | Approved | Most recent IF: 3.836; 2006 IF: 3.107 | |||
| Call Number | UA @ lucian @ | Serial | 4428 | ||
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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. | ||||
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| Language | Wos | 000237950400042 | Publication Date | 2006-05-11 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121 | ISBN | Additional Links |
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| Impact Factor | 3.836 | Times cited | 5 | Open Access | |
| Notes | Approved | Most recent IF: 3.836; 2006 IF: 3.107 | |||
| Call Number | UA @ lucian @ | Serial | 4429 | ||
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| Author | N. Gauquelin, E. Benckiser, M. K. Kinyanjui, M. Wu, Y. Lu, G. Christiani, G. Logvenov, H.-U. Habermeier, U. Kaiser, B. Keimer, and G. A. Botton | ||||
| Title | Atomically resolved EELS mapping of the interfacial structure of epitaxially strained LaNiO3/LaAlO3 superlattices | Type | A1 Journal Article | ||
| Year | 2014 | Publication | Physical Review B | Abbreviated Journal | |
| Volume | 90 | Issue | Pages | 195140 | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | The interfacial atomic structure of a metallic LaNiO3/LaAlO3 superlattice grown on a LaSrAlO4 substrate was investigated using a combination of atomically resolved electron energy loss spectroscopy (EELS) at the Al K, Al L2,3, Sr L2,3, Ni L2,3, La M4,5, and O K edges as well as hybridization mapping of selected features of the O K-edge fine structure.We observe an additional La1−xSrxAl1−yNiyO3 layer at the substrate-superlattice interface, possibly linked to diffusion of Al and Sr into the growing film or a surface reconstruction due to Sr segregation. The roughness of the LaNiO3/LaAlO3 interfaces is found to be on average around one pseudocubic unit cell. The O K-edge EELS spectra revealed reduced spectral weight of the prepeak derived from Ni-O hybridized states in the LaNiO3 layers. We rule out oxygen nonstoichiometry of the LaNiO3 layers and discuss changes in the Ni-O hybridization due to heterostructuring as possible origin. |
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| Language | Wos | 000345467000003 | Publication Date | 2014-11-20 | |
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| Impact Factor | Times cited | 17 | Open Access | ||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | EMAT @ emat @ | Serial | 4544 | ||
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