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Author Komendová, L.; Milošević, M.V.; Shanenko, A.A.; Peeters, F.M.
Title Different length scales for order parameters in two-gap superconductors : extended Ginzburg-Landau theory Type A1 Journal article
Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 84 Issue (up) 6 Pages 064522-064522,5
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using the Ginzburg-Landau theory extended to the next-to-leading order, we determine numerically the healing lengths of the two order parameters at the two-gap superconductor/normal metal interface. We demonstrate on several examples that those can be different even in the strict domain of applicability of the Ginzburg-Landau theory. This justifies the use of this theory to describe relevant physics of two-gap superconductors, distinguishing them from their single-gap counterparts. The calculational degree of complexity increases only slightly with respect to the conventional Ginzburg-Landau expansion, thus the extended Ginzburg-Landau model remains numerically far less demanding compared to the full microscopic approaches.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000294226000013 Publication Date 2011-08-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 56 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-INSTANS network. ; Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:92414 Serial 695
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Author Berdiyorov, G.R.; Yu, S.H.; Xiao, Z.L.; Peeters, F.M.; Hua, J.; Imre, A.; Kwok, W.K.
Title Effect of sample geometry on the phase boundary of a mesoscopic superconducting loop Type A1 Journal article
Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B
Volume 80 Issue (up) 6 Pages 064511,1-064511,6
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We studied the effect of sample geometry on the evolution of the superconducting state in nanoscale Nb circular and square loops by transport measurements. A multistage resistive transition with temperature is found for both samples, which is related to the effect of contact leads made from the same superconducting material. The H-T phase diagrams close to Tc0 show clear periodic oscillations on top of a parabolic background, i.e., Little-Parks effect. However, the amplitude of the oscillations decreases faster in the circular loop compared to the one in the square sample. Numerical simulations are conducted within the nonlinear Ginzburg-Landau theory to show the effect of sample geometry on the nucleation of superconductivity in superconducting loop structures.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000269638800067 Publication Date 2009-08-17
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 21 Open Access
Notes Approved Most recent IF: 3.836; 2009 IF: 3.475
Call Number UA @ lucian @ c:irua:78292 Serial 833
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Author Doria, M.M.; Romaguera, A.R. de C.; Peeters, F.M.
Title Effect of the boundary condition on the vortex patterns in mesoscopic three-dimensional superconductors: disk and sphere Type A1 Journal article
Year 2007 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 75 Issue (up) 6 Pages 064505,1-6
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000244533000072 Publication Date 2007-02-14
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 37 Open Access
Notes Approved Most recent IF: 3.836; 2007 IF: 3.172
Call Number UA @ lucian @ c:irua:63791 Serial 844
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Author Bourgeois, J.; Hervieu, M.; Poienar, M.; Abakumov, A.M.; Elkaïm, E.; Sougrati, M.T.; Porcher, F.; Damay, F.; Rouquette, J.; Van Tendeloo, G.; Maignan, A.; Haines, J.; Martin, C.;
Title Evidence of oxygen-dependent modulation in LuFe2O4 Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 85 Issue (up) 6 Pages 064102-064120,10
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A polycrystalline sample of LuFe2O4 has been investigated by means of powder synchrotron x-ray and neutron diffraction and transmission electron microscopy (TEM), along with Mössbauer spectroscopy and transport and magnetic properties. A monoclinic distortion is unambiguously evidenced, and the crystal structure is refined in the monoclinic C2/m space group [aM = 5.9563(1) Å, bM = 3.4372(1) Å, cM = 8.6431(1) Å, β = 103.24(1)°]. Along with the previously reported modulations distinctive of the charge-ordering (CO) of the iron species, a new type of incommensurate order is observed, characterized by a vector q⃗1 = α1a⃗M* + γ1c⃗M* (with α1 ≅ 0.55, γ1 ≅ 0.13). In situ heating TEM observations from 300 to 773 K confirm that the satellites associated with q⃗1 vanish completely, only at a temperature significantly higher than the CO temperature. This incommensurate modulation has a displacive character and corresponds primarily to a transverse displacive modulation wave of the Lu cations position, as revealed by the high resolution, high angle annular dark field scanning TEM images and in agreement with synchrotron data refinements. Analyses of vacuum-annealed samples converge toward the hypothesis of a new ordering mechanism, associated with a tiny oxygen deviation from the O4 stoichiometry.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000299896900003 Publication Date 2012-02-06
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 24 Open Access
Notes Hercules Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:95042 Serial 1095
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Author Zha, G.-Q.; Chen, Y.; Peeters, F.M.; Zhou, S.-P.
Title Impurity-induced modulations of orders in d-wave superconductors Type A1 Journal article
Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B
Volume 80 Issue (up) 6 Pages 064518,1-064518,5
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract By using a model Hamiltonian with competing antiferromagnetic (AFM) and d-wave superconductivity orders, the impurity-induced structures of orders in d-wave superconductors is investigated. We find that the transition between one-dimensional stripe and two-dimensional checkerboardlike modulation around a single nonmagnetic impurity can take place as the strength of the AFM interaction U or the impurity scattering strength V0 is varied. It is also found that the impurity-induced stripe can first transit to checkerboardlike modulation and then disappears with increasing the next-nearest-neighbor hopping strength |t|. Phase diagrams of V0 versus U and |t| for various modulations of the spin order are presented. In addition, the quantum interference effect on the modulations of orders due to two strong nonmagnetic impurities is briefly examined, and the checkerboardlike and quasistripe patterns can occur depending on the sites where two impurities are placed.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000269638800074 Publication Date 2009-09-01
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 3 Open Access
Notes Approved Most recent IF: 3.836; 2009 IF: 3.475
Call Number UA @ lucian @ c:irua:78293 Serial 1572
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Author Zhao, H.-W.; Zha, G.-Q.; Zhou, S.-P.; Peeters, F.M.
Title Long-range Coulomb repulsion effect on a charged vortex in high-temperature superconductors with competing d-wave and antiferromagnetic orders Type A1 Journal article
Year 2008 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B
Volume 78 Issue (up) 6 Pages 064505,1-064505,5
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Vortex charges in high-temperature superconductor (HTS) are studied by solving the Bogoliubovde Gennes equations based on a model Hamiltonian with antiferromagnetic (AF) and d-wave orders in the presence of the long-range Coulomb repulsion. For a sufficient strength of the AF order, the negative vortex charge is found. A sign change between negative and positive may occur by tuning the long-range Coulomb repulsion strength or the doping parameter. Recent NMR experiments are hopefully understood. We show that the charged vortex can induce a spin-orbit coupling that is important for superconductors with a short coherence length and a large value of the energy gap over the Fermi-level ratio. Fractional flux quanta are possible for HTS.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000259264900084 Publication Date 2008-08-06
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 12 Open Access
Notes Approved Most recent IF: 3.836; 2008 IF: 3.322
Call Number UA @ lucian @ c:irua:76553 Serial 1837
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Author Neek-Amal, M.; Xu, P.; Qi, D.; Thibado, P.M.; Nyakiti, L.O.; Wheeler, V.D.; Myers-Ward, R.L.; Eddy, C.R.; Gaskill, D.K.; Peeters, F.M.
Title Membrane amplitude and triaxial stress in twisted bilayer graphene deciphered using first-principles directed elasticity theory and scanning tunneling microscopy Type A1 Journal article
Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 90 Issue (up) 6 Pages 064101
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Twisted graphene layers produce a moire pattern (MP) structure with a predetermined wavelength for a given twist angle. However, predicting the membrane corrugation amplitude for any angle other than pure AB-stacked or AA-stacked graphene is impossible using first-principles density functional theory (DFT) due to the large supercell. Here, within elasticity theory, we define the MP structure as the minimum-energy configuration, thereby leaving the height amplitude as the only unknown parameter. The latter is determined from DFT calculations for AB-and AA-stacked bilayer graphene in order to eliminate all fitting parameters. Excellent agreement with scanning tunneling microscopy results across multiple substrates is reported as a function of twist angle.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000339995800001 Publication Date 2014-08-01
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 12 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. M.N.-A. was supported by the EU-Marie Curie IIF postdoctoral Fellowship No. 299855. P.M.T. is thankful for the financial support of the Office of Naval Research under Grant No. N00014-10-1-0181 and the National Science Foundation under Grant No. DMR-0855358. L.O.N. acknowledges the support of the American Society for Engineering Education and Naval Research Laboratory Postdoctoral Fellow Program. Work at the US Naval Research Laboratory is supported by the Office of Naval Research. ; Approved Most recent IF: 3.836; 2014 IF: 3.736
Call Number UA @ lucian @ c:irua:118774 Serial 1991
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Author Gou, H.; Tsirlin, A.A.; Bykova, E.; Abakumov, A.M.; Van Tendeloo, G.; Richter, A.; Ovsyannikov, S.V.; Kurnosov, A.V.; Trots, D.M.; Konôpková, Z.; Liermann, H.P.; Dubrovinsky, L.; Dubrovinskaia, N.;
Title Peierls distortion, magnetism, and high hardness of manganese tetraboride Type A1 Journal article
Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 89 Issue (up) 6 Pages 064108-64109
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report crystal structure, electronic structure, and magnetism of manganese tetraboride, MnB4, synthesized under high-pressure, high-temperature conditions. In contrast to superconducting FeB4 and metallic CrB4, which are both orthorhombic, MnB4 features a monoclinic crystal structure. Its lower symmetry originates from a Peierls distortion of the Mn chains. This distortion nearly opens the gap at the Fermi level, but despite the strong dimerization and the proximity of MnB4 to the insulating state, we find indications for a sizable paramagnetic effective moment of about 1.7 mu(B)/f.u., ferromagnetic spin correlations, and, even more surprisingly, a prominent electronic contribution to the specific heat. However, no magnetic order has been observed in standard thermodynamic measurements down to 2 K. Altogether, this renders MnB4 a structurally simple but microscopically enigmatic material; we argue that its properties may be influenced by electronic correlations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000332405000002 Publication Date 2014-02-24
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 39 Open Access
Notes Approved Most recent IF: 3.836; 2014 IF: 3.736
Call Number UA @ lucian @ c:irua:115819 Serial 2571
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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 (up) 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.
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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 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 Holden, T.; Habermeier, H.-U.; Cristiani, G.; Golnik, A.; Boris, A.; Pimenov, A.; Humlicek, J.; Lebedev, O.I.; Van Tendeloo, G.; Keimer, B.; Bernhard, C.
Title Proximity induced metal-insulator transition in YBa2Cu3O7/La2/3Ca1/3MnO3 superlattices Type A1 Journal article
Year 2004 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 69 Issue (up) 6 Pages 064505,1-064505,7
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The far-infrared dielectric response of superlattices (SL) composed of superconducting YBa2Cu3O7 (YBCO) and ferromagnetic La0.67Ca0.33MnO3 (LCMO) has been investigated by ellipsometry. A drastic decrease of the free-carrier response is observed which involves an unusually large length scale of d(crit)approximate to20 nm in YBCO and d(crit)approximate to10 nm in LCMO. A corresponding suppression of metallicity is not observed in SL's where LCMO is replaced by the paramagnetic metal LaNiO3. Our data suggest that either a long-range charge transfer from the YBCO to the LCMO layers or alternatively a strong coupling of the charge carriers to the different and competitive kind of magnetic correlations in the LCMO and YBCO layers is at the heart of the observed metal-insulator transition. The low free-carrier response observed in the far-infrared dielectric response of the magnetic superconductor RuSr2GdCu2O8 is possibly related to this effect.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000220092100066 Publication Date 2004-02-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 101 Open Access
Notes Approved Most recent IF: 3.836; 2004 IF: 3.075
Call Number UA @ lucian @ c:irua:54743 Serial 2734
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Author Tsirlin, A.A.; Abakumov, A.M.; Ritter, C.; Rosner, H.
Title (CuCl)LaTa2O\text{7} and quantum phase transition in the (CuX)LaM2O7 family (X=Cl, Br; M=Nb, Ta) Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 86 Issue (up) 6 Pages 064440-12
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We apply neutron diffraction, high-resolution synchrotron x-ray diffraction, magnetization measurements, electronic structure calculations, and quantum Monte-Carlo simulations to unravel the structure and magnetism of (CuCl)LaTa2O7. Despite the pseudo-tetragonal crystallographic unit cell, this compound features an orthorhombic superstructure, similar to the Nb-containing (CuX)LaNb2O7 with X = Cl and Br. The spin lattice entails dimers formed by the antiferromagnetic fourth-neighbor coupling J(4), as well as a large number of nonequivalent interdimer couplings quantified by an effective exchange parameter J(eff). In (CuCl)LaTa2O7, the interdimer couplings are sufficiently strong to induce the long-range magnetic order with the Neel temperature T-N similar or equal to 7 K and the ordered magnetic moment of 0.53 mu(B), as measured with neutron diffraction. This magnetic behavior can be accounted for by J(eff)/J(4) similar or equal to 1.6 and J(4) similar or equal to 16 K. We further propose a general magnetic phase diagram for the (CuCl)LaNb2O7-type compounds, and explain the transition from the gapped spin-singlet (dimer) ground state in (CuCl)LaNb2O7 to the long-range antiferromagnetic order in (CuCl)LaTa2O7 and (CuBr)LaNb2O7 by an increase in the magnitude of the interdimer couplings J(eff)/J(4), with the (CuCl)LaM2O7 (M = Nb, Ta) compounds lying on different sides of the quantum critical point that separates the singlet and long-range-ordered magnetic ground states.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000308127600006 Publication Date 2012-08-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 6 Open Access
Notes Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:101886 Serial 3526
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Author Ghorbanfekr-Kalashami, H.; Peeters, F.M.; Novoselov, K.S.; Neek-Amal, M.
Title Spatial design and control of graphene flake motion Type A1 Journal article
Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 96 Issue (up) 6 Pages 060101
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000406860300001 Publication Date 2017-08-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 3 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program. M.N.-A. was supported by Iran National Science Foundation (INSF). K.S.N. was supported by the EU Graphene Flagship Program, European Research Council Synergy Grant Hetero2D, the Royal Society, Engineering and Physical Research Council (UK), US Army Research Office. ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:145166 Serial 4724
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Author Wang, W.; Van Duppen, B.; Van der Donck, M.; Peeters, F.M.
Title Magnetopolaron effect on shallow-impurity states in the presence of magnetic and intense terahertz laser fields in the Faraday configuration Type A1 Journal article
Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 97 Issue (up) 6 Pages 064108
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The magnetopolaron effect on shallow-impurity states in semiconductors is investigated when subjected simultaneously to a magnetic field and an intense terahertz laser field within the Faraday configuration. We use a time-dependent nonperturbative theory to describe electron interactions. The externally applied fields are exactly included via a laser-dressed interaction potential. Through a variational approach we evaluate the binding energy of the shallow-impurity states. We find that the interaction strength of the laser-dressed Coulomb potential can not only be enhanced but also weakened by varying the two external fields. In this way, the binding energy can be tuned by the external fields and red-or blue-shifted with respect to the static binding energy. In the nonresonant polaron region, a magnetopolaron correction that includes the effects of photon process is observed. In the resonant polaron region, moreover, the resonant magnetopolaron effect accompanied by the emission and absorption of a single photon is distinctly observed. This can be modulated to be far away from the reststrahlen band. The intriguing findings of this paper can be observed experimentally and, in turn, provide a way to measure the strength of the electron-phonon interaction.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000426041900004 Publication Date 2018-02-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 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 by the National Natural Science Foundation of China (Grants No. 11404214 and No. 11455015) and the China Scholarship Council (CSC), Anhui Provincial Natural Science Foundation (Grant No. 1408085QA13), Key Projects of Anhui Provincial Department of Education (Grants No. KJ2017A406 and No. KJ2017A401). B.V.D. was financially supported by the Research Science Foundation-Flanders (FWO-Vl) through a postdoctoral fellowship and M.V.d.D. was financially supported by the Research Science Foundation-Flanders (FWO-Vl) through a doctoral fellowship. ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:149906UA @ admin @ c:irua:149906 Serial 4942
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Author Mulkers, J.; Hals, K.M.D.; Leliaert, J.; Milošević, M.V.; Van Waeyenberge, B.; Everschor-Sitte, K.
Title Effect of boundary-induced chirality on magnetic textures in thin films Type A1 Journal article
Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 98 Issue (up) 6 Pages 064429
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract In the quest for miniaturizing magnetic devices, the effects of boundaries and surfaces become increasingly important. Here we show how the recently predicted boundary-induced Dzyaloshinskii-Moriya interaction (DMI) affects the magnetization of ferromagnetic films with a C-infinity v symmetry and a perpendicular magnetic anisotropy. For an otherwise uniformly magnetized film, we find a surface twist when the magnetization in the bulk is canted by an in-plane external field. This twist at the surfaces caused by the boundary-induced DMI differs from the common canting caused by internal DMI observed at the edges of a chiral magnet. Furthermore, we find that the surface twist due to the boundary-induced DMI strongly affects the width of the domain wall at the surfaces. We also find that the skyrmion radius increases in the depth of the film, with the average size of the skyrmion increasing with boundary-induced DMI. This increase suggests that the boundary-induced DMI contributes to the stability of the skyrmion.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication New York, N.Y Editor
Language Wos 000443394600004 Publication Date 2018-08-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 9 Open Access
Notes ; The authors thank Matthias Sitte and Andre Thiaville for fruitful discussions. This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vlaanderen) through Project No. G098917N and the German Research Foundation (DFG) under the Project No. EV 196/2-1. J.L. is supported by the Ghent University Special Research Fund with a BOF postdoctoral fellowship. ; Approved Most recent IF: 3.836
Call Number UA @ lucian @ c:irua:153706UA @ admin @ c:irua:153706 Serial 5093
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Author Lozano, D.P.; Couet, S.; Petermann, C.; Hamoir, G.; Jochum, J.K.; Picot, T.; Menendez, E.; Houben, K.; Joly, V.; Antohe, V.A.; Hu, M.Y.; Leu, B.M.; Alatas, A.; Said, A.H.; Roelants, S.; Partoens, B.; Milošević, M.V.; Peeters, F.M.; Piraux, L.; Van de Vondel, J.; Vantomme, A.; Temst, K.; Van Bael, M.J.
Title Experimental observation of electron-phonon coupling enhancement in Sn nanowires caused by phonon confinement effects Type A1 Journal article
Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B
Volume 99 Issue (up) 6 Pages 064512
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Reducing the size of a superconductor below its characteristic length scales can either enhance or suppress its critical temperature (T-c). Depending on the bulk value of the electron-phonon coupling strength, electronic and phonon confinement effects will play different roles in the modification of T-c. Experimentally disentangling each contribution has remained a challenge. We have measured both the phonon density of states and T-c of Sn nanowires with diameters of 18, 35, and 100 nm in order to quantify the effects of phonon confinement on superconductivity. We observe a shift of the phonon frequency towards the low-energy region and an increase in the electron-phonon coupling constant that can account for the measured increase in T-c.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000459322400005 Publication Date 2019-02-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 11 Open Access
Notes ; We would like to thanks Jeroen Scheerder and Wout Keijers for their help and assistance during the low-temperature measurements. This work was supported by the Research Foundation Flanders (FWO), the Concerted Research Action (GOA/14/ 007), the Federation Wallonie-Bruxelles (ARC 13/18-052, Supracryst) and the Fonds de la Recherche Scientifique -FNRS under Grant No. T.0006.16. The authors acknowledge Hercules Stichting (Project Nos. AKUL/13/19 and AKUL/13/25). D.P.L. thanks the FWO for financial support. This research used resources of the Advanced Photon Source, a US Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. ; Approved Most recent IF: 3.836
Call Number UA @ admin @ c:irua:158621 Serial 5212
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Author Wang, J.; Andelkovic, M.; Wang, G.; Peeters, F.M.
Title Molecular collapse in graphene: Sublattice symmetry effect Type A1 Journal article
Year 2020 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 102 Issue (up) 6 Pages 064108-8
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Atomic collapse can be observed in graphene because of its large “effective” fine structure constant, which enables this phenomenon to occur for an impurity charge as low as Z(c) similar to 1-2. Here we investigate the effect of the sublattice symmetry on molecular collapse in two spatially separated charge tunable vacancies, which are located on the same (A-A type) or different (A-B type) sublattices. We find that the broken sublattice symmetry: (1) does not affect the location of the main bonding and antibonding molecular collapse peaks, (2) but shifts the position of the satellite peaks, because they are a consequence of the breaking of the local sublattice symmetry, and (3) there are vacancy characteristic collapse peaks that only occur for A-B type vacancies, which can be employed to distinguish them experimentally from the A-A type. As the charge, energy, and separation distance increase, the additional collapse features merge with the main molecular collapse peaks. We show that the spatial distribution around the vacancy site of the collapse states allows us to differentiate the molecular from the frustrated collapse.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000562320700002 Publication Date 2020-08-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.7 Times cited 3 Open Access
Notes ; This work was supported by the National Natural Science Foundation of China (Grants No. 61874038 and No. 61704040), National Key R&D Program Grant 2018YFE0120000, the scholarship from China Scholarship Council (CSC: 201908330548), and TRANS2DTMD FlagEra project. ; Approved Most recent IF: 3.7; 2020 IF: 3.836
Call Number UA @ admin @ c:irua:172065 Serial 6562
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Author Zhang, L.; Zhang, Y.-Y.; Zha, G.-Q.; Milošević, M.V.; Zhou, S.-P.
Title Skyrmionic chains and lattices in s plus id superconductors Type A1 Journal article
Year 2020 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 101 Issue (up) 6 Pages 064501
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We report characteristic vortex configurations in s + id superconductors with time-reversal symmetry breaking, exposed to magnetic field. A vortex in the s + id state tends to have an opposite phase winding between s- and d-wave condensates. We find that this peculiar feature together with the competition between s- and d-wave symmetry results in three distinct classes of vortical configurations. When either s or d condensate absolutely dominates, vortices form a conventional lattice. However, when one condensate is relatively dominant, vortices organize in chains that exhibit skyrmionic character, separating the chiral components of the s +/- id order parameter into domains within and outside the chain. Such skyrmionic chains are found stable even at high magnetic field. When s and d condensates have comparable strength, vortices split cores in two chiral components to form full-fledged skyrmions, i.e., coreless topological structures with an integer topological charge, organized in a lattice. We provide characteristic magnetic field distributions of all states, enabling their identification in, e.g., scanning Hall probe and scanning SQUID experiments. These unique vortex states are relevant for high-T-c cuprate and iron-based superconductors, where the relative strength of competing pairing symmetries is expected to be tuned by temperature and/or doping level, and can help distinguish s + is and s + id superconducting phases.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000510745600005 Publication Date 2020-02-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.7 Times cited 7 Open Access
Notes ; The authors acknowledge useful discussions with Yong-Ping Zhang. This research was supported by the National Natural Science Foundation of China under Grants No. 61571277 and No. 61771298. L.-F.Z. and M.V.M. acknowledge support from Research Foundation-Flanders (FWO-Vlaanderen). ; Approved Most recent IF: 3.7; 2020 IF: 3.836
Call Number UA @ admin @ c:irua:166507 Serial 6605
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Author Van der Donck, M.; Conti, S.; Perali, A.; Hamilton, A.R.; Partoens, B.; Peeters, F.M.; Neilson, D.
Title Three-dimensional electron-hole superfluidity in a superlattice close to room temperature Type A1 Journal article
Year 2020 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 102 Issue (up) 6 Pages 060503
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Although there is strong theoretical and experimental evidence for electron-hole superfluidity in separated sheets of electrons and holes at low T, extending superfluidity to high T is limited by strong two-dimensional fluctuations and Kosterlitz-Thouless effects. We show this limitation can be overcome using a superlattice of alternating electron- and hole-doped semiconductor monolayers. The superfluid transition in a three-dimensional superlattice is not topological, and for strong electron-hole pair coupling, the transition temperature T-c can be at room temperature. As a quantitative illustration, we show T-c can reach 270 K for a superfluid in a realistic superlattice of transition metal dichalcogenide monolayers.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000562320700001 Publication Date 2020-08-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.7 Times cited 8 Open Access
Notes ; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for M.V.d.D., by the FLAG-ERA project TRANS-2D-TMD, and by the Australian Government through the Australian Research Council Centre of Excellence in Future Low-Energy Electronics (Project No. CE170100039). We thank Milorad V. Milossevi ' c, Pierbiagio Pieri, and Jacques Tempere for helpful discussions. ; Approved Most recent IF: 3.7; 2020 IF: 3.836
Call Number UA @ admin @ c:irua:172064 Serial 6628
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Author Chwiej, T.; Bednarek, S.; Adamowski, J.; Peeters, F.M.
Title Broken one-particle symmetry in few-electron coupled quantum dots Type A1 Journal article
Year 2006 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 73 Issue (up) 7 Pages 075422,1-10
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000235668900113 Publication Date 2006-02-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 4 Open Access
Notes Approved Most recent IF: 3.836; 2006 IF: 3.107
Call Number UA @ lucian @ c:irua:57003 Serial 257
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Author Vagov, A.; Glaessl, M.; Croitoru, M.D.; Axt, V.M.; Kuhn, T.
Title Competition between pure dephasing and photon losses in the dynamics of a dot-cavity system Type A1 Journal article
Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 90 Issue (up) 7 Pages 075309
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We demonstrate that in quantum-dot cavity systems, the interplay between acoustic phonons and photon losses introduces novel features and characteristic dependencies in the system dynamics. In particular, the combined action of both dephasing mechanisms strongly affects the transition from the weak-to the strong-coupling regime as well as the shape of the spectral triplet that represents the quantum-dot occupation in Fourier space. The width of the central peak in the triplet is expected to decrease with rising temperature, while the widths and heights of the side peaks depend nonmonotonically on the dot-cavity coupling.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000341258700002 Publication Date 2014-08-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 11 Open Access
Notes ; We acknowledge fruitful discussions with A. Nazir which helped us to more clearly formulate the relation between our phenomenological approach and the microscopic theory. M.D.C. further acknowledges Alexander von Humboldt and BELSPO grants for support. Financial support from the Deutsche Forschungsgemeinschaft (Grant No. AX 17/7-1) is also gratefully acknowledged. ; Approved Most recent IF: 3.836; 2014 IF: 3.736
Call Number UA @ lucian @ c:irua:119257 Serial 437
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Author Klimczuk, T.; Wang, C.H.; Lawrence, J.M.; Xu, Q.; Durakiewicz, T.; Ronning, F.; Llobet, A.; Trouw, F.; Kurita, N.; Tokiwa, Y.; Lee, H.o.; Booth, C.H.; Gardner, J.S.; Bauer, E.D.; Joyce, J.J.; Zandbergen, H.W.; Movshovich, R.; Cava, R.J.; Thompson, J.D.;
Title Crystal fields, disorder, and antiferromagnetic short-range order in Yb0.24Sn0.76Ru Type A1 Journal article
Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 84 Issue (up) 7 Pages 075152-075152,8
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report extensive measurements on a new compound (Yb0.24Sn0.76)Ru that crystallizes in the cubic CsCl structure. Valence-band photoemission (PES) and L3 x-ray absorption show no divalent component in the 4f configuration of Yb. Inelastic neutron scattering (INS) indicates that the eight-fold degenerate J-multiplet of Yb3+ is split by the crystalline electric field (CEF) into a Γ7-doublet ground state and a Γ8 quartet at an excitation energy 20 meV. The magnetic susceptibility can be fit very well by this CEF scheme under the assumption that a Γ6-excited state resides at 32 meV; however, the Γ8/Γ6 transition expected at 12 meV was not observed in the INS. The resistivity follows a Bloch-Grüneisen law shunted by a parallel resistor, as is typical of systems subject to phonon scattering with no apparent magnetic scattering. All of these properties can be understood as representing simple local moment behavior of the trivalent Yb ion. At 1 K there is a peak in specific heat that is too broad to represent a magnetic-phase transition, consistent with absence of magnetic reflections in neutron diffraction. On the other hand this peak also is too narrow to represent the Kondo effect in the Γ7-doublet ground state. On the basis of the field dependence of the specific heat, we argue that antiferromagnetic (AF) short-range order (SRO) (possibly coexisting with Kondo physics) occurs at low temperatures. The long-range magnetic order is suppressed because the Yb site occupancy is below the percolation threshold for this disordered compound.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000293830800003 Publication Date 2011-08-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 8 Open Access
Notes Esteem 026019 Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:92427 Serial 555
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Author Xu, W.; Peeters, F.M.; Lu, T.C.
Title Dependence of resistivity on electron density and temperature in graphene Type A1 Journal article
Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B
Volume 79 Issue (up) 7 Pages 073403,1-073403,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract On the basis of the momentum-balance equation derived from the Boltzmann equation in which electron interactions with impurities and acoustic and optic phonons are included, we examine the dependence of the resistivity in graphene on temperature and electron density. Simple analytical expressions for the different contributions to the resistivity are obtained. Our results reproduce recent experimental findings and we are able to understand the different temperature dependence of the resistivity for low and high density samples.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000263815800013 Publication Date 2009-02-12
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 31 Open Access
Notes Approved Most recent IF: 3.836; 2009 IF: 3.475
Call Number UA @ lucian @ c:irua:76222 Serial 642
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Author Stopa, T.; Szafran, B.; Tavernier, M.B.; Peeters, F.M.
Title Dependence of the vortex structure in quantum dots on the range of the inter-electron interaction Type A1 Journal article
Year 2006 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 73 Issue (up) 7 Pages 075315,1-9
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000235668900075 Publication Date 2006-02-10
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 7 Open Access
Notes Approved Most recent IF: 3.836; 2006 IF: 3.107
Call Number UA @ lucian @ c:irua:57002 Serial 646
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Author Anisimovas, E.; Peeters, F.M.
Title Dynamic response of artificial bipolar molecules Type A1 Journal article
Year 2002 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 66 Issue (up) 7 Pages 075311
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We calculate the equilibrium properties and the dynamic response of two vertically coupled circular quantum dots populated by particles of different electrical charge sign, i.e., electrons and holes. The equilibrium density profiles are obtained and used to compute the frequencies and oscillator strengths of magnetoplasma excitations. We find a strong coupling between the modes derived from the center-of-mass modes of the individual dots which leads to an anticrossing with a pronounced oscillator strength transfer from the “acoustic” to the “optical” branch. Also, due to the breaking of the generalized Kohn theorem a number of other than center-of-mass modes are excited whose oscillator strengths, however, are rather weak.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000177969800103 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 UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 9 Open Access
Notes Approved Most recent IF: 3.836; 2002 IF: NA
Call Number UA @ lucian @ c:irua:99397 Serial 765
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Author Li, B.; Djotyan, A.P.; Hao, Y.L.; Avetisyan, A.A.; Peeters, F.M.
Title Effect of a perpendicular magnetic field on the shallow donor states near a semiconductor-metal interface Type A1 Journal article
Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 87 Issue (up) 7 Pages 075313-75319
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We investigate the influence of an external perpendicular magnetic field on the lowest-energy states of an electron bound to a donor which is located near a semiconductor-metal interface. The problem is treated within the effective mass approach and the lowest-energy states are obtained through (1) the “numerically exact” finite element method, and (2) a variational approach using a trial wave function where all image charges that emerge due to the presence of the metallic gate are taken into account. The trial wave functions are constructed such that they reduce to an exponential behavior for sufficiently small magnetic fields and become Gaussian for intermediate and large magnetic fields. The average electron-donor distance can be controlled by the external magnetic field. We find that the size of the 2p(z) state depends strongly on the magnetic field when the donor is close to the interface, showing a nonmonotonic behavior, in contrast with the ground and the other excited states. DOI: 10.1103/PhysRevB.87.075313
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000314874800017 Publication Date 2013-02-13
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 1 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 3.836; 2013 IF: 3.664
Call Number UA @ lucian @ c:irua:107664 Serial 793
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Author Nogaret, A.; Peeters, F.M.
Title Electrically induced spin resonance fluorescence: 1: theory Type A1 Journal article
Year 2007 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 76 Issue (up) 7 Pages
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We calculate the fluorescence of electron spins confined to a plane and driven into resonance by a magnetic field gradient and a constant magnetic field applied at right angles to each other. We solve the equation of motion of two-dimensional electrons in the magnetic field gradient to derive the dispersion curve of spin oscillators, the amplitude of electron oscillations, the effective magnetic field sensed by the electron spin, and the rate at which electrons are injected from an electrode into spin oscillators. We then switch on the interaction between the spin magnetic dipole and the electromagnetic field to find the fluorescence power radiated by the individual spin oscillators. The rate of radiative decay is first derived, followed by the probability of sequential photon emission whereby a series of spontaneous decays occurs at random times separated by intervals during which the spin performs Rabi oscillations. The quantum correlations between random radiative decays manifest as bursts of emission at regular intervals along the wire. We integrate all multiphoton processes to obtain an exact analytical expression for the radiated electromagnetic power. The present theory obtains all parameters of the problem including magnetodipole coupling, the particle dwell time in the magnetic field gradient, and the spin polarization of the incoming current. The output power contains a fine structure arising from the anharmonicity of electron oscillations and from nonlinear optical effects which both give satellite emission peaks at odd multiples of the fundamental frequency.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000249155300091 Publication Date 2007-08-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 8 Open Access
Notes Approved Most recent IF: 3.836; 2007 IF: 3.172
Call Number UA @ lucian @ c:irua:66117 Serial 897
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Author Nogaret, A.; Lambert, N.J.; Peeters, F.M.
Title Electrically induced spin resonance fluorescence : 2 : fluorescence spectra Type A1 Journal article
Year 2007 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 76 Issue (up) 7 Pages
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We model the fluorescence spectra of planar spin oscillators to find conditions that maximize spin resonance fluorescence. Spin oscillators perform Rabi oscillations under the effect of a periodic effective magnetic field caused by the winding motion of an electron in a gradient of magnetic field. We show that, despite the weak coupling of the spin magnetic dipole to the vacuum, spin oscillators excited by a direct current output a few nanowatts of microwave power, which is comparable to the best microwave sources. The large quantum efficiency relies on the combination of two effects. On the one hand, the spontaneous emission rate is enhanced by the synchronization of spin oscillators, which interact through the microwave field that they emit. On the other hand, the huge Rabi frequencies experienced by spin oscillators promote spins into upper levels of Zeeman transitions, from which a radiative cascade is triggered. We demonstrate different regimes of fluorescence which correspond to different values of the Rabi period relative to the spontaneous decay time and to the oscillator dwell time in the gradient of magnetic field. We investigate the device parameters which make these regimes experimentally accessible and find conditions that optimize microwave output. We find that microwave emission is centered around the cutoff frequency of spin oscillators. This has the advantage that the peak emission frequency may be tuned from zero continuously up to a few hundred gigahertz using an electrostatic gate. Quite remarkably for a spintronics effect, electrically induced spin resonance fluorescence does not require the injection of a spin polarized current. In fact, we show that microwave spectra are mostly independent of the incoming spin polarization except for magnetic waveguides which are shorter than a certain critical length, which we will specify.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000249155300092 Publication Date 2007-08-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 8 Open Access
Notes Approved Most recent IF: 3.836; 2007 IF: 3.172
Call Number UA @ lucian @ c:irua:66118 Serial 898
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Author Hai, G.Q.; Peeters, F.M.; Devreese, J.T.
Title Electron optical-phonon coupling in GaAs/AlxGa1-xAs quantum wells due to interface, slab and half-space modes Type A1 Journal article
Year 1993 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 48 Issue (up) 7 Pages 4666-4674
Keywords A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos A1993LW02600057 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 102 Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:5748 Serial 981
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Author Barbier, M.; Vasilopoulos, P.; Peeters, F.M.
Title Extra Dirac points in the energy spectrum for superlattices on single-layer graphene Type A1 Journal article
Year 2010 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 81 Issue (up) 7 Pages 075438,1-075438,7
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We investigate the emergence of extra Dirac points in the electronic structure of a periodically spaced barrier system, i.e., a superlattice, on single-layer graphene, using a Dirac-type Hamiltonian. Using square barriers allows us to find analytic expressions for the occurrence and location of these new Dirac points in k space and for the renormalization of the electron velocity near them in the low-energy range. In the general case of unequal barrier and well widths the new Dirac points move away from the Fermi level and for given heights of the potential barriers there is a minimum and maximum barrier width outside of which the new Dirac points disappear. The effect of these extra Dirac points on the density of states and on the conductivity is investigated.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000274998200133 Publication Date 2010-02-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 211 Open Access
Notes ; This work was supported by IMEC, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), the Brazilian Council for Research (CNPq), and the Canadian NSERC Grant No. OGP0121756. ; Approved Most recent IF: 3.836; 2010 IF: 3.774
Call Number UA @ lucian @ c:irua:81767 Serial 1159
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Author Partoens, B.; Peeters, F.M.
Title From graphene to graphite: electronic structure around the K point Type A1 Journal article
Year 2006 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 74 Issue (up) 7 Pages 075404,1-11
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000240238800090 Publication Date 2006-08-03
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 738 Open Access
Notes Approved Most recent IF: 3.836; 2006 IF: 3.107
Call Number UA @ lucian @ c:irua:60807 Serial 1282
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