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Author Berdiyorov, G.R.; Chao, X.H.; Peeters, F.M.; Wang, H.B.; Moshchalkov, V.V.; Zhu, B.Y.
Title Magnetoresistance oscillations in superconducting strips : a Ginzburg-Landau study Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 86 Issue 22 Pages 224504-224508
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Within the time-dependent Ginzburg-Landau theory we study the dynamic properties of current-carrying superconducting strips in the presence of a perpendicular magnetic field. We found pronounced voltage peaks as a function of the magnetic field, the amplitude of which depends both on sample dimensions and external parameters. These voltage oscillations are a consequence of moving vortices, which undergo alternating static and dynamic phases. At higher fields or for high currents, the continuous motion of vortices is responsible for the monotonic background on which the resistance oscillations due to the entry of additional vortices are superimposed. Mechanisms for such vortex-assisted resistance oscillations are discussed. Qualitative changes in the magnetoresistance curves are observed in the presence of random defects, which affect the dynamics of vortices in the system.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000312064300004 Publication Date 2012-12-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 31 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the ESF-NES program. G. R. B. acknowledges support from FWO-Vl. B.Y.Z. acknowledges the support from the MOST 973 Projects No. 2011CBA00110 and No. 2009CB930803, and the National Natural Science Foundation of China. V. V. M. acknowledges support from the Methusalem Funding by the Flemish Government. ; Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:105969 Serial 1930
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Author Geurts, R.; Milošević, M.V.; Albino Aguiar, J.; Peeters, F.M.
Title Enhanced stability of vortex-antivortex states in two-component mesoscopic superconductors Type A1 Journal article
Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 87 Issue 2 Pages 024501-24508
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using the Ginzburg-Landau (GL) theory, we calculate the stability of sample symmetry-induced vortex-antivortex molecules in a mesoscopic superconducting bilayer exposed to a homogeneous magnetic field. We demonstrate the conditions under which the two condensates cooperatively broaden the field-temperature stability range of the composite (joint) vortex-antivortex state. In cases when such broadening is not achieved, a reentrance of the vortex-antivortex state is found at lower temperatures. In a large portion of the phase diagram noncomposite states are possible, in which the antivortex is present in only one of the layers. In this case, we demonstrate that the vortex-antivortex molecule in one of the layers can be pinned and enlarged by interaction with a vortex molecule in the other. Using analogies in the respective GL formalisms, we map our findings for the bilayer onto mesoscopic two-band superconductors.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000313029800003 Publication Date 2013-01-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 25 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen), the Brazilian science agencies FACEPE/CNPq under Grant No. APQ-0589-1.05/08 and CNPq under Grant No. 309832/2007-1, and the CNPq-FWO cooperation program under Grant No. 490681/2010-7. M.V.M. acknowledges support from the CAPES-PVE program. ; Approved Most recent IF: 3.836; 2013 IF: 3.664
Call Number UA @ lucian @ c:irua:105925 Serial 1058
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Author Van Aert, S.; de Backer, A.; Martinez, G.T.; Goris, B.; Bals, S.; Van Tendeloo, G.; Rosenauer, A.
Title Procedure to count atoms with trustworthy single-atom sensitivity Type A1 Journal article
Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 87 Issue 6 Pages 064107-6
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report a method to reliably count the number of atoms from high-angle annular dark field scanning transmission electron microscopy images. A model-based analysis of the experimental images is used to measure scattering cross sections at the atomic level. The high sensitivity of these measurements in combination with a thorough statistical analysis enables us to count atoms with single-atom sensitivity. The validity of the results is confirmed by means of detailed image simulations. We will show that the method can be applied to nanocrystals of arbitrary shape, size, and atom type without the need for a priori knowledge about the atomic structure.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000315144700006 Publication Date 2013-02-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 106 Open Access
Notes FWO; 262348 ESMI; 312483 ESTEEM2;246791 COUNTATOMS; Hercules 3; esteem2_jra2 Approved Most recent IF: 3.836; 2013 IF: 3.664
Call Number UA @ lucian @ c:irua:105674 Serial 2718
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Author Sofo, J.O.; Suarez, A.M.; Usaj, G.; Cornaglia, P.S.; Hernández-Nieves, A.D.; Balseiro, C.A.
Title Electrical control of the chemical bonding of fluorine on graphene Type A1 Journal article
Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 83 Issue 8 Pages 081411
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the electronic structure of diluted F atoms chemisorbed on graphene using density functional theory calculations. We show that the nature of the chemical bonding of a F atom adsorbed on top of a C atom in graphene strongly depends on carrier doping. In neutral samples the F impurities induce a sp(3)-like bonding of the C atom below, generating a local distortion of the hexagonal lattice. As the graphene is electron-doped, the C atom retracts back to the graphene plane and for high doping (10(14) cm(-2)) its electronic structure corresponds to a nearly pure sp(2) configuration. We interpret this sp(3)-sp(2) doping-induced crossover in terms of a simple tight-binding model and discuss the physical consequences of this change.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000287484800005 Publication Date 2011-02-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 65 Open Access
Notes ; J.O.S. and A. S. acknowledge support from the Donors of the American Chemical Society Petroleum Research Fund and use of facilities at the Penn State Materials Simulation Center. G. U., P. S. C., A. D. H., and C. A. B. acknowledge financial support from PICTs 06-483 and 2008-2236 from ANPCyT and PIP 11220080101821 from CONICET, Argentina. A. D. H. acknowledges support from the Flemish Science Foundation (FWO). ; Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:105600 Serial 892
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Author Vodolazov, D.Y.; Peeters, F.M.
Title Origin of the hysteresis of the current voltage characteristics of superconducting microbridges near the critical temperature Type A1 Journal article
Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 84 Issue 9 Pages 094511
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The current voltage (IV) characteristics of short [with length L less than or similar to xi(T)] and long [L >> xi(T)] microbridges are theoretically investigated near the critical temperature of the superconductor. Calculations are made in the nonlocal (local) limit when the inelastic relaxation length due to electron-phonon interactions L(in) = (D tau(in))(1/2) is larger (smaller) than the temperature-dependent coherence length xi(T) (D is the diffusion coefficient, tau(in) is the inelastic relaxation time of the quasiparticle distribution function). We find that, in both limits, the origin of the hysteresis in the IV characteristics is mainly connected with the large time scale over which the magnitude of the order parameter varies in comparison with the time-scale variation of the superconducting phase difference across the microbridge in the resistive state. In the nonlocal limit, the time-averaged heating and cooling of quasiparticles are found in different areas of the microbridge, which are driven, respectively, by oscillations of the order parameter and the electric field. We show that, by introducing an additional term in the time-dependent Ginzburg-Landau equation, it is possible to take into account the cooling effect in the local limit too.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000294920900009 Publication Date 2011-09-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 7 Open Access
Notes ; This work was supported by the Russian Foundation for Basic Research, Russian Agency of Education under the Federal Target Programme“Scientific and educational personnel of innovative Russia in 2009-2013,” the Flemish Science Foundation (FWO-Vl), and the Belgian Science Policy (IAP). ; Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:105573 Serial 2527
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Author Dixit, H.; Lamoen, D.; Partoens, B.
Title Quasiparticle band structure of rocksalt-CdO determined using maximally localized Wannier functions Type A1 Journal article
Year 2013 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 25 Issue 3 Pages 035501-35505
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract CdO in the rocksalt structure is an indirect band gap semiconductor. Thus, in order to determine its band gap one needs to calculate the complete band structure. However, in practice, the exact evaluation of the quasiparticle band structure for the large number of k-points which constitute the different symmetry lines in the Brillouin zone can be an extremely demanding task compared to the standard density functional theory (DFT) calculation. In this paper we report the full quasiparticle band structure of CdO using a plane-wave pseudopotential approach. In order to reduce the computational effort and time, we make use of maximally localized Wannier functions (MLWFs). The MLWFs offer a highly accurate method for interpolation of the DFT or GW band structure from a coarse k-point mesh in the irreducible Brillouin zone, resulting in a much reduced computational effort. The present paper discusses the technical details of the scheme along with the results obtained for the quasiparticle band gap and the electron effective mass.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000313100500010 Publication Date 2012-12-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 7 Open Access
Notes Fwo Approved Most recent IF: 2.649; 2013 IF: 2.223
Call Number UA @ lucian @ c:irua:105296 Serial 2801
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Author Galván Moya, J.E.; Nelissen, K.; Peeters, F.M.
Title Structural transitions in vertically and horizontally coupled parabolic channels of Wigner crystals Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 86 Issue 18 Pages 184102-184109
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Structural phase transitions in two vertically or horizontally coupled channels of strongly interacting particles are investigated. The particles are free to move in the x direction but are confined by a parabolic potential in the y direction. They interact with each other through a screened power-law potential (r(-n)e(-r/lambda)). In vertically coupled systems, the channels are stacked above each other in the direction perpendicular to the (x, y) plane, while in horizontally coupled systems both channels are aligned in the confinement direction. Using Monte Carlo (MC) simulations we obtain the ground-state configurations and the structural transitions as a function of the linear particle density and the separation between the channels. At zero temperature, the vertically coupled system exhibits a rich phase diagram with continuous and discontinuous transitions. On the other hand, the horizontally coupled system exhibits only a very limited number of phase transitions due to its symmetry. Further, we calculated the normal modes for the Wigner crystals in both cases. From MC simulations, we found that in the case of vertically coupled systems, the zigzag transition is only possible for low densities. A Ginzburg-Landau theory for the zigzag transition is presented, which predicts correctly the behavior of this transition from which we interpret the structural phase transition of the Wigner crystal through the reduction of the Brillouin zone.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000310683600002 Publication Date 2012-11-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 6 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:105150 Serial 3271
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Author Muñoz, W.A.; Covaci, L.; Peeters, F.M.
Title Tight-binding study of bilayer graphene Josephson junctions Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 86 Issue 18 Pages 184505-184507
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using highly efficient simulations of the tight-binding Bogoliubov-de-Gennes model, we solved self-consistently for the pair correlation and the Josephson current in a superconducting-bilayer graphene-superconducting Josephson junction. Different doping levels for the non-superconducting link are considered in the short- and long-junction regimes. Self-consistent results for the pair correlation and superconducting current resemble those reported previously for single-layer graphene except at the Dirac point, where remarkable differences in the proximity effect are found, as well as a suppression of the superconducting current in the long-junction regime. Inversion symmetry is broken by considering a potential difference between the layers and we found that the supercurrent can be switched if the junction length is larger than the Fermi length.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000310840400005 Publication Date 2012-11-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 13 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-VI). ; Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:105149 Serial 3661
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Author Sarmadian, N.; Saniz, R.; Lamoen, D.; Partoens, B.
Title Influence of Al concentration on the optoelectronic properties of Al-doped MgO Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 86 Issue 20 Pages 205129-5
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract We use density functional theory within the local density approximation to investigate the structural, electronic, and optical properties of Al-doped MgO. The concentrations considered range from 6% to 56%. In the latter case, we also compare the optical properties of the amorphous and crystalline phases. We find that, overall, the electronic properties of the crystalline phases change qualitatively little with Al concentration. On the other hand, the changes in the electronic structure in the amorphous phase are more important, most notably because of deep impurity levels in the band gap that are absent in the crystalline phase. This leads to observable effects in, e.g., the optical absorption edge and in the refractive index. Thus, the latter can be used to characterize the crystalline to amorphous transition with Al doping level.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000311605000003 Publication Date 2012-11-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 5 Open Access
Notes Iwt; Fwo Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:105137 Serial 1612
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Author Beheshtian, J.; Sadeghi, A.; Neek-Amal, M.; Michel, K.H.; Peeters, F.M.
Title Induced polarization and electronic properties of carbon-doped boron nitride nanoribbons Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 86 Issue 19 Pages 195433-195438
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The electronic properties of boron nitride nanoribbons (BNNRs) doped with a line of carbon atoms are investigated using density functional calculations. By replacing a line of alternating B and N atoms with carbons, three different configurations are possible depending on the type of the atoms which bond to the carbons. We found very different electronic properties for these configurations: (i) the NCB arrangement is strongly polarized with a large dipole moment having an unexpected direction, (ii) the BCB and NCN arrangements are nonpolar with zero dipole moment, (iii) the doping by a carbon line reduces the band gap regardless of the local arrangement of the borons and the nitrogens around the carbon line, and (iv) the polarization and energy gap of the carbon-doped BNNRs can be tuned by an electric field applied parallel to the carbon line. Similar effects were found when either an armchair or zigzag line of carbon was introduced.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000311694200006 Publication Date 2012-11-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 41 Open Access
Notes ; We would like to thank J. M. Pereira and S. Goedecker for helpful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the ESF-EuroGRAPHENE project CONGRAN. M. N.-A is supported by EU-Marie Curie IIF postdoc Fellowship/299522. ; Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:105136 Serial 1603
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Author Callebaut, A.K.; Michel, K.H.
Title Microscopic theory of orientational disorder and lattice instability in solid C70 Type A1 Journal article
Year 1995 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 52 Issue 21 Pages 15279-15290
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We have developed a microscopic theory which describes the orientational dynamics of C-70 molecules and its coupling to lattice displacements in the face-centered-cubic phase of C-70 fullerite. The single-molecule orientational density distribution in the disordered phase is calculated. The ferroelastic transition to the rhombohedral phase is investigated. The discontinuity of the orientational order parameter at the phase transition is calculated. It is found that the transition leads to a stretching of the primitive unit cell along a [111] cubic direction. A softening of the elastic constant c(44) at the transition is predicted.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos A1995TK97900042 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 (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.736 Times cited 20 Open Access
Notes Approved PHYSICS, APPLIED 28/145 Q1 #
Call Number UA @ lucian @ c:irua:104421 Serial 2031
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Author Copley, J.R.D.; Michel, K.H.
Title Multiple orientational order parameters in solid C60 Type A1 Journal article
Year 1997 Publication Physica: B : condensed matter T2 – International Conference on Neutron Scattering, AUG 17-21, 1997, TORONTO, CANADA Abbreviated Journal Physica B
Volume 241 Issue Pages 454-455
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The transition Fm (3) over bar m -->Pa (3) over bar in solid C-60 is driven by the condensation of orientational modes belonging to X-5(+) irreducible representations (irreps) of Fm (3) over bar m. Taking into account irreps up to the manifold l = 12, we have studied the primary and secondary orientational order parameters loops). We have numerically solved the coupled molecular field equations for these oops and calculated the temperature dependence of Bragg reflection intensities. (C) 1998 Elsevier Science B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000074062600130 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4526; ISBN Additional Links (down) UA library record; WoS full record
Impact Factor 1.386 Times cited Open Access
Notes Approved Most recent IF: 1.386; 1997 IF: 0.991
Call Number UA @ lucian @ c:irua:104360 Serial 2228
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Author Seo, J.W.; Schryvers, D.; Vermeulen, W.; Richard, O.; Potapov, P.
Title Electron microscopy investigation of ternary \gamma-brass-type precipitation in a Ni39.6Mn47.5Ti12.9 alloy Type A1 Journal article
Year 1999 Publication Philosophical magazine: A: physics of condensed matter: defects and mechanical properties Abbreviated Journal Philos Mag A
Volume 79 Issue 6 Pages 1279-1294
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract Homogenized Ni39.6Mn47.5T12.9 material was investigated by different electron microscopy techniques. Apart from the martensite precursor distortions typical for B2 phase alloys undergoing a thermoelastic martensitic transformation upon cooling, coherent dodecahedron-shaped precipitates with sizes between 20 and 100 nm and faceted by lozenge shapes of {110}-type planes are observed. Selected-area and microdiffraction patterns reveal an overall unit cell with a size of 3 x 3 x 3 units of the bcc lattice of the matrix and a body-centred symmetry without screw axes. Finally a ternary gamma-brass-type atomic structure of space group 14(3) over bar m is suggested for these precipitates in accordance with the obtained symmetry constraints, the energy-dispersive X-ray measurements and high-resolution transmission electron microscopy images. This is the first time this type of structure is found in an alloy completely consisting of transition-metal elements.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000080687900002 Publication Date 2007-07-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0141-8610;1460-6992; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 3 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:104297 Serial 956
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Author Maignan, A.; Martin, C.; Van Tendeloo, G.; Hervieu, M.; Raveau, B.
Title Size mismatch : a crucial factor for generating a spin-glass insulator in manganites Type A1 Journal article
Year 1999 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 60 Issue 22 Pages 15214-15219
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Thr structural, electronic, and magnetic properties of the highly mismatched perovskite oxides, Th(0.35)A(0.65)MnO(3), where Ais for the alkaline earth divalent cations (Ca, Ba, Sr), which are all characterized by the same large tolerance factor (t=0.934), have been investigated by using electron microscopy, electrical resistivity, magnetic susceptibility, and magnetization. It is clearly established that a transition from ferromagnetic metallic towards spin-glass insulator samples is induced as the A-site cationic size mismatch is increased. Moreover, the magnetoresistance (MR) properties of these manganites are strongly reduced for the spin-glass insulators, demonstrating that the A-sire cationic disorder is detrimental for the colossal MR properties. Based on these results, a new electronic and magnetic diagram is established that shows that the A-site disorder, rather than the A-site average cationic size (or t) is the relevant factor for generating spin-glass insulating manganites. [S0163-1829(99)01746-4].
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000084631600039 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 (down) 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; 1999 IF: NA
Call Number UA @ lucian @ c:irua:104280 Serial 3038
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Author Anisimovas, E.; Peeters, F.M.
Title Correlated few-particle states in artificial bipolar molecule Type A1 Journal article
Year 2002 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 65 Issue 23 Pages 233302-233304
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We investigate the ground and excited states of a bipolar artificial molecule composed of two vertically coupled quantum dots containing different type of carriers-electrons and holes-in equilibrium. The approach based on exact diagonalization is used and reveals an intricate pattern of ground-state angular momentum switching and a rearrangement of approximate single-particle levels as a function of the interdot coupling strength.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000176767900019 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 (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 14 Open Access
Notes Approved Most recent IF: 3.836; 2002 IF: NA
Call Number UA @ lucian @ c:irua:104154 Serial 519
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Author Vodolazov, D.Y.; Baelus, B.J.; Peeters, F.M.
Title Stationary-phase slip state in quasi-one-dimensional rings Type A1 Journal article
Year 2002 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 66 Issue 5 Pages 054531-54536
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The nonuniform superconducting state in a ring in which the order parameter vanishing at one point is studied. This state is characterized by a jump of the phase by pi at the point where the order parameter becomes zero. In uniform rings such a state is a saddle-point state and consequently unstable. However, for nonuniform rings with, e.g., variations of geometrical or physical parameters or with attached wires this state can be stabilized and may be realized experimentally.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000177873000137 Publication Date 2002-10-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 29 Open Access
Notes Approved Most recent IF: 3.836; 2002 IF: NA
Call Number UA @ lucian @ c:irua:104147 Serial 3152
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Author Peeters, F.M.; Vasilopoulos, P.; Shi, J.
Title Density of states and Fermi level of a periodically modulated two-dimensional electron gas Type A1 Journal article
Year 2002 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 14 Issue 38 Pages 8803-8816
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Explicit analytic expressions are obtained for the density of states D(E) and Fermi energy E-F of a two-dimensional electron gas in the presence of a weak and periodic unidirectional electric or magnetic modulation and of a uniform perpendicular magnetic field B. The Landau levels broaden into bands and their width, proportional to the modulation strength, oscillates with B and gives rise to Weiss oscillations in D(E), E-F and the transport coefficients. When both electric and magnetic modulations are present the position of the resulting oscillations depends on the ratio delta between the two modulation strengths. When the modulations are out of phase there is no shift in the position of the oscillations when delta varies and for a particular value of delta the oscillations are suppressed.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000178678400008 Publication Date 2002-09-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 8 Open Access
Notes Approved Most recent IF: 2.649; 2002 IF: 1.775
Call Number UA @ lucian @ c:irua:104140 Serial 640
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Author Ferreira, W.P.; Matulis, A.; Farias, G.A.; Peeters, F.M.
Title Structure and correlations in two-dimensional classical artificial atoms confined by a Coulomb potential Type A1 Journal article
Year 2003 Publication Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E
Volume 67 Issue 4Part 2 Pages 046601-46608
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The ordering of N equally charged particles (-e) moving in two dimensions and confined by a Coulomb potential, resulting from a displaced positive charge Ze is discussed. This is a classical model system for atoms. We obtain the configurations of charged particles which, depending on the value of N and Z, may result in ring structures, hexagonal-type configurations, and for N/Z approximate to 1 in an inner structure of particles which is separated by an outer ring of particles. For N/Z << 1, the Hamiltonian of the parabolic confinement case is recovered. For N/Z approximate to 1, the configurations are very different from those found in the case of a parabolic confinement potential. A hydrodynamic analysis is presented in order to highlight the correlations effects.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor
Language Wos 000182825400087 Publication Date 2003-04-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1063-651X;1095-3787; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 14 Open Access
Notes Approved Most recent IF: 2.366; 2003 IF: 2.202
Call Number UA @ lucian @ c:irua:104123 Serial 3273
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Author Verberck, B.; Nikolaev, A.V.; Michel, K.H.
Title Orientational charge density waves and the metal-insulator transition in polymerized KC60 Type A1 Journal article
Year 2005 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 71 Issue 16 Pages 165117-11
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract A theoretical model is presented for the description of the metal-insulator transition which accompanies the structural phase transition at T approximate to 50 K in polymerized KC60. The model involves orientational charge density waves (along the C-60 polymer chains) which were introduced previously for a description of the structural phase transition. A satisfactory qualitative and quantitative understanding is obtained when the three-dimensionality of the crystal and the presence of the K+ counterions is properly taken into account.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000228763100035 Publication Date 2005-04-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links (down) 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; 2005 IF: 3.185
Call Number UA @ lucian @ c:irua:104076 Serial 2514
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Author Krstajic, P.; Peeters, F.M.
Title Spin-dependent tunneling in diluted magnetic semiconductor trilayer structures Type A1 Journal article
Year 2005 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 72 Issue 12 Pages 125350-125356
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Tunneling of holes through a trilayer structure made of two diluted magnetic semiconductors, (Ga,Mn)As, separated by a thin layer of nonmagnetic AlAs is investigated. The problem is treated within the 6x6 Luttinger-Kohn model for valence bands with the split-off band included. The influence of the spin-orbit coupling is pronounced as the spin-splitting Delta(ex) is comparable with the split-off Delta(SO) splitting. It is assumed that direct tunneling is the dominant mechanism due to the high quality of the tunnel junctions. Our theoretical results predict the correct order of magnitude for the tunneling magnetoresistance ratio, but various other effects, such as scattering on impurities and defects, should be included in order to realize a quantitative agreement with experiment.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000232229400116 Publication Date 2005-09-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 8 Open Access
Notes Approved Most recent IF: 3.836; 2005 IF: 3.185
Call Number UA @ lucian @ c:irua:104068 Serial 3086
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Author Ferreira, W.P.; Peeters, F.M.; Farias, G.A.
Title Melting and evaporation in classical two-dimensional clusters confined by a Coulomb potential Type A1 Journal article
Year 2005 Publication Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E
Volume 72 Issue 4 Part 1 Pages 041502-41507
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The thermal properties of a two-dimensional classical cluster of negatively charged particles bound by a punctual positive charge are presented. The melting phenomenon is analyzed and the features which characterize such a solid-liquid transition are highlighted. We found that the presence of metastable states strongly modifies the melting scenario, and that the melting temperature of the system is determined by the height of the saddle point energy separating the ground state and the metastable state. Due to the particular type of confinement potential considered in this paper, we also found that, at sufficiently large temperature, the cluster can become thermally ionized.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor
Language Wos 000232930600030 Publication Date 2005-10-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1539-3755;1550-2376; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.366 Times cited 4 Open Access
Notes Approved Most recent IF: 2.366; 2005 IF: 2.418
Call Number UA @ lucian @ c:irua:104067 Serial 1983
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Author Vagov, A.; Schomerus, H.; Shanenko, A.
Title Generalized Galitskii approach for the vertex function of a Fermi gas with resonant interaction Type A1 Journal article
Year 2007 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 76 Issue 21 Pages 214513-214517
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present a generalized Galitskii approach for the Bethe-Salpeter equation for the two-particle vertex function of a Fermi system with the resonant interaction by accounting for the resonant state in the scattering potential and utilizing the universal form of the resonant scattering amplitude. The procedure can be carried out both for the normal as well as for the condensate state. In both cases, the vertex function in the vicinity of the resonance is shown to formally coincide with that obtained for a weakly attractive Fermi gas. Thus we justify the popular calculational framework in which results for the weakly attractive Fermi gas are formally extrapolated into the domain of strong coupling, and further to the repulsive side of the resonance, where molecular states are formed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000251986100097 Publication Date 2007-12-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links (down) 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; 2007 IF: 3.172
Call Number UA @ lucian @ c:irua:104037 Serial 1324
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Author Dzhurakhalov, A.A.; Atanasov, I.; Hou, M.
Title Calculation of binary and ternary metallic immiscible clusters with icosahedral structures Type A1 Journal article
Year 2008 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume Issue Pages 115415
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Recently, core-shell Ag-Co, Ag-Cu, and “onionlike” Cu-Co equilibrium configurations were predicted in the case of isolated face centered cubic (fcc) bimetallic clusters, and three shell onionlike configurations were predicted in the case of ternary metallic clusters with spherical and truncated octahedral morphologies. In the present paper, immiscible binary CuCo and ternary AgCuCo clusters with icosahedral structures are studied as functions of their size and composition. Clusters studied are formed by 13, 55, 147, 309, and 561 atoms corresponding to the five smallest possible closed shell icosahedral structures. An embedded atom model potential is used to describe their cohesion. Equilibrium configurations are investigated by means of Metropolis Monte Carlo free energy minimization in the (NPT) canonical ensemble. Most simulations are achieved at 10 and 300 K. The effect of temperature on segregation ordering is systematically investigated. Selected cases are used to identify the effect of size and composition on melting. In contrast with fcc clusters, homogeneous onionlike configurations of binary clusters are not predicted. When it is allowed by the composition, a complete outer shell is formed by Cu in binary Cu-Co clusters and by Ag in ternary Ag-Cu-Co clusters. Depending on temperature, Co may precipitate into decahedral groups under the Cu vertices of the icosahedra in binary clusters, while the Co-Cu configuration in ternary clusters drastically depends on the Ag coating. Despite the multicomponent character of the clusters and the immiscibility of the species forming them, for most compositions and sizes, equilibrium structures remain close to perfectly icosahedral at 10 K as well as at 300 K.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000254542800167 Publication Date 2008-03-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121; 1550-235x ISBN Additional Links (down) 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; 2008 IF: 3.322
Call Number UA @ lucian @ c:irua:104033 Serial 4517
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Author Sudheendra, L.; Moshnyaga, V.; Lebedev, O.I.; Gehrke, K.; Belenciuc, A.; Shapoval, O.; Van Tendeloo, G.; Samwer, K.
Title A-site ordering and stripe phases in manganite films Type A1 Journal article
Year 2008 Publication Physica: B : condensed matter T2 – International Conference on Strongly Correlated Electron Systems (SCES, 2007), MAY 13-18, 2007, Houston, TX Abbreviated Journal Physica B
Volume 403 Issue 5-9 Pages 1645-1646
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Insulating and metallic stripes above and below the Curie temperature, T-C, respectively, were observed by a high-resolution scanning tunneling microscopy (STM) and/or spectroscopy (STS) in A-site ordered and macroscopically strain free epitaxial La0.75Ca0.25MnO3 film grown on MgO substrate. The “insulating” stripes were found to be incommensurable to the lattice and aligned along (110) direction. Metallic stripes were commensurable with periodicity 2a(p)similar to 0.8 nm and aligned parallel to the crystallographic a/b-axis. Formation of these stripes involves competing charge, orbital, and lattice orders and is an outcome of an overlapping of electron wave functions mediated by the local lattice-strain distribution, existed even in A-site ordered film due to the difference in cation radii of La and Ca. (C) 2007 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000254689900330 Publication Date 2007-11-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4526; ISBN Additional Links (down) UA library record; WoS full record
Impact Factor 1.386 Times cited Open Access
Notes Approved Most recent IF: 1.386; 2008 IF: 0.822
Call Number UA @ lucian @ c:irua:104031 Serial 26
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Author Baelus, B.J.; Yampolskii, S.V.; Peeters, F.M.; Montevecchi, E.; Indekeu, J.O.
Title Superconducting properties of mesoscopic cylinders with enhanced surface superconductivity Type A1 Journal article
Year 2002 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 65 Issue 2 Pages 024510-10
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The superconducting state of an infinitely long superconducting cylinder surrounded by a medium which enhances its superconductivity near the boundary is studied within the nonlinear Ginzburg-Landau theory. This enhancement can be due to the proximity of another superconductor or due to surface treatment. Quantities such as the free energy, the magnetization and the Cooper-pair density are calculated. Phase diagrams are obtained to investigate how the critical field and the critical temperature depend on this surface enhancement for different values of the Ginzburg-Landau parameter kappa. Increasing the superconductivity near the surface leads to higher critical fields and critical temperatures. For small cylinder diameters only giant vortex states nucleate, while for larger cylinders multivortices can nucleate. The stability of these multivortex states also depends on the surface enhancement. For type-I superconductors we found the remarkable result that for a range of values of the surface extrapolation length the superconductor can transit from the Meissner state into superconducting states with vorticity L > 1. Such a behavior is not found for the case of large kappa, i.e., type-II superconductivity,
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000173213100099 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 (down) 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; 2002 IF: NA
Call Number UA @ lucian @ c:irua:103890 Serial 3363
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Author Wang, Z.-H.; Kronmüller, H.; Lebedev, O.I.; Gross, G.M.; Razavi, F.S.; Habermeier, H.U.; Shen, B.G.
Title Phase transition and magnetic anisotropy of (La,Sr)MnO3 thin films Type A1 Journal article
Year 2002 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 65 Issue 5 Pages 054411-54416
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The magnetic proper-ties and their correlation with the microstructure and electrical transport are investigated in La0.88Sr0.1MnO3 films grown on (100)SrTiO3 Single crystal substrates with thickness ranging from 100 to 2500 Angstrom. The ultrathin film (t = 100 Angstrom) has a single ferromagnetic transition (FMT) at T-c of 250 K, whereas the thicker films exhibit two FMTs, with the main one at a lowered T-c of 200 K while the minor one around 300 K. Furthermore, a thickness dependent magnetic anisotropy has been found, strongly indicating the existence of strain effect, which is also revealed by the transmission electron microscopy study. The suppressed Jahn-Teller distortion (JTD) by the epitaxial strain, and the recovered JTD due to the strain relexation are suggested to explain the metallic behavior in thin films and the insulating behavior in the thick film (t = 2500 Angstrom), repectively.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000173647000058 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 (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 23 Open Access
Notes Approved Most recent IF: 3.836; 2002 IF: NA
Call Number UA @ lucian @ c:irua:103883 Serial 2592
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Author Ivanov, V.A.; Krstajic, P.M.; Peeters, F.M.; Fleurov, V.; Kikoin, K.
Title On the ferromagnetic exchange in Mn-doped III-V semiconductors Type A1 Journal article
Year 2003 Publication Physica: B : condensed matter T2 – 23rd International Conference on Low Temperature Physics (LT23), AUG 20-27, 2002, HIROSHIMA, JAPAN Abbreviated Journal Physica B
Volume 329 Issue Part 2 Pages 1282-1283
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We propose a microscopic model for double exchange in GaAs:Mn, GaP:Mn which is based on the interaction between the transition metal impurities and the heavy holes of host semiconductor. The kinematic exchange is derived and the Curie temperature is calculated which agrees with recent experiments. (C) 2003 Elsevier Science B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000183802700400 Publication Date 2003-02-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4526; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.386 Times cited 5 Open Access
Notes Approved Most recent IF: 1.386; 2003 IF: 0.908
Call Number UA @ lucian @ c:irua:103813 Serial 2435
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Author Blumenau, A.T.; Jones, R.; Frauenheim, T.; Willems, B.; Lebedev, O.I.; Van Tendeloo, G.; Fisher, D.; Martineau, P.M.
Title Dislocations in diamond : dissociation into partials and their glide motion Type A1 Journal article
Year 2003 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 68 Issue 1 Pages 014115-14119
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The dissociation of 60degrees and screw dislocations in diamond is modeled in an approach combining isotropic elasticity theory with ab initio-based tight-binding total-energy calculations. Both dislocations are found to dissociate with a substantial lowering of their line energies. For the 60degrees dislocation, however, an energy barrier to dissociation is found. We investigate the core structure of a screw dislocation distinguishing “shuffle,” “mixed,” and “glide” cores. The latter is found to be the most stable undissociated screw dislocation. Further, the glide motion of 90degrees and 30degrees partials is discussed in terms of a process involving the thermal formation and subsequent migration of kinks along the dislocation line. The calculated activation barriers to dislocation motion show that the 30degrees partial is less mobile than the 90degrees partial. Finally, high-resolution electron microscopy is performed on high-temperature, high-pressure annealed natural brown diamond, allowing the core regions of 60degrees dislocations to be imaged. The majority of dislocations are found to be dissociated. However, in some cases, undissociated 60degrees dislocations were also observed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000184582900050 Publication Date 2003-08-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 39 Open Access
Notes Approved Most recent IF: 3.836; 2003 IF: NA
Call Number UA @ lucian @ c:irua:103800 Serial 734
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Author de Gryse, O.; Vanhellemont, J.; Clauws, P.; Lebedev, O.; van Landuyt, J.; Simoen, E.; Claeys, C.
Title A novel approach to analyse FTIR spectra of precipitates in boron-doped silicon Type A1 Journal article
Year 2003 Publication Physica: B : condensed matter T2 – 22nd International Conference on Defects in Semiconductors (ICDS-22), JUL 28-AUG 01, 2003, UNIV AARHUS, AARHUS, DENMARK Abbreviated Journal Physica B
Volume 340 Issue Pages 1013-1017
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Infrared absorption spectra of composite precipitates are analysed with a modified Day-Thorpe algorithm, assuming a precipitated phase consisting of a mixture of two components with known optical properties. Additional constraints are introduced when solving the model equations by using a priori knowledge making the algorithm more reliable. It is shown that this novel approach allows determining both morphology and composition of precipitates. The method is applied to characterise oxide precipitates in boron-doped silicon. The results indicate that for the resistivity range above 60 mOmegacm, the precipitated phase is most probably SiO1.17+/-0.14, while for resistivities below 20 mOmega cm, precipitates consist of a SiO2/B2O3 composite with a large volume fraction of B(2)0(3) (up to 40% for 8 mOmegacm material). (C) 2003 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000188300200213 Publication Date 2003-11-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4526; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.386 Times cited 4 Open Access
Notes Approved Most recent IF: 1.386; 2003 IF: 0.908
Call Number UA @ lucian @ c:irua:103784 Serial 25
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Author Papp, G.; Peeters, F.M.
Title Giant magnetoresistance in a two-dimensional electron gas modulated by magnetic barriers Type A1 Journal article
Year 2004 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 16 Issue 46 Pages 8275-8283
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The temperature-dependent giant magnetoresistance effect is investigated in a magnetically modulated two-dimensional electron gas, which can be realized by depositing two parallel ferromagnets on the top and bottom of a heterostructure. The effective potential for electrons arising for parallel magnetization allows the electrons to resonantly tunnel through the magnetic barriers, while this is excluded in the anti-parallel situation. Such a discrepancy results in a giant magnetoresistance ratio (MRR), which can be up to 10(31)%. The MRR shows a strong dependence on temperature, but our study indicates that for realistic parameters for a GaAs heterostructure the effect can be as high as 10(4)% at 4 K.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000225706000017 Publication Date 2004-11-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984;1361-648X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 69 Open Access
Notes Approved Most recent IF: 2.649; 2004 IF: 2.049
Call Number UA @ lucian @ c:irua:103718 Serial 1338
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