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“Giant Pd clusters observed by HREM”. Volkov VV, Van Tendeloo G, Vargaftik MN, Stolygarov IP, Moiseev II, Mendeleev communications , 187 (1993)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.34
Times cited: 10
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“Ginzburg-Landau theory and effects of pressure on a two-band superconductor : application to MgB2”. Betouras JJ, Ivanov VA, Peeters FM, European physical journal : B : condensed matter and complex systems 31, 349 (2003). http://doi.org/10.1140/epjb/e2003-00041-7
Abstract: We present a model of pressure effects of a two-band superconductor based on a Ginzburg-Landau free energy with two order parameters. The parameters of the theory are pressure as well as temperature dependent. New pressure effects emerge as a result of the competition between the two bands. The theory then is applied to MgB2. We identify two possible scenaria regarding the fate of the two Q subbands under pressure, depending on whether or not both subbands are above the Fermi energy at ambient pressure. The splitting of the two subbands is probably caused by the E-2g, distortion. If only one subband is above the Fermi energy at ambient pressure (scenario I), application of pressure diminishes the splitting and it is possible that the lower subband participates in the superconductivity. The corresponding crossover pressure and Gruneisen parameter are estimated. In the second scenario both bands start above the Fermi energy and they move below it, either by pressure or via the substitution of Mg by Al. In both scenaria, the possibility of electronical topological transition is emphasized. Experimental signatures of both scenaria are presented and existing experiments are discussed in the light of the different physical pictures.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.461
Times cited: 10
DOI: 10.1140/epjb/e2003-00041-7
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“How do plasma-generated OH radicals react with biofilm components? Insights from atomic scale simulations”. Khosravian N, Bogaerts A, Huygh S, Yusupov M, Neyts EC, Biointerphases 10, 029501 (2015). http://doi.org/10.1116/1.4904339
Abstract: The application of nonthermal atmospheric pressure plasma is emerging as an alternative and efficient technique for the inactivation of bacterial biofilms. In this study, reactive molecular dynamics simulations were used to examine the reaction mechanisms of hydroxyl radicals, as key reactive oxygen plasma species in biological systems, with several organic molecules (i.e., alkane, alcohol, carboxylic acid, and amine), as prototypical components of biomolecules in the biofilm. Our results demonstrate that organic molecules containing hydroxyl and carboxyl groups may act as trapping agents for the OH radicals. Moreover, the impact of OH radicals on N-acetyl-glucosamine, as constituent component of staphylococcus epidermidis biofilms, was investigated. The results show how impacts of OH radicals lead to hydrogen abstraction and subsequent molecular damage. This study thus provides new data on the reaction mechanisms of plasma species, and particularly the OH radicals, with fundamental components of bacterial biofilms.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 2.603
Times cited: 10
DOI: 10.1116/1.4904339
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“Hydrogeochemical exploration for gold in the Osilo area, Sardinia, Italy”. Cidu R, Fanfani L, Shand P, Edmunds WM, Van 't dack L, Gijbels R, Applied geochemistry 10, 517 (1995). http://doi.org/10.1016/0883-2927(95)00022-4
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 2.268
Times cited: 10
DOI: 10.1016/0883-2927(95)00022-4
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“Hydrothermal processing of barium strontium titanate sol-gel composite thin films”. Zelonka K, Sayer M, Freundorfer AP, Hadermann J, Journal of materials science 41, 3885 (2006). http://doi.org/10.1007/s10853-005-5525-4
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.599
Times cited: 10
DOI: 10.1007/s10853-005-5525-4
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“Interband magnetooptical studies of resonant polaron coupling in CdTe/Cd1-xMnxTe quantum-wells”. Nicholas RJ, Sasaki S, Miura N, Peeters FM, Shi JM, Hai GQ, Devreese JT, Lawless MJ, Ashenford DE, Lunn B, Physical Review B 50, 7596 (1994). http://doi.org/10.1103/PhysRevB.50.7596
Abstract: Magnetoreflectivity measurements of the 1s and 2s exciton energies in a CdTe/Cd1-xMnxTe superlattice have been made in magnetic fields up to 45 T, showing the resonant polaron coupling of electrons to LO phonons. Strong reflectivity features are seen for both the 1s and 2s excitons, which show a strong field-dependent spin splitting due to the dilute magnetic barriers. At B-z=0, the 2s exciton feature is observed lying 18 meV above the Is state, and is shifted upward in energy by the magnetic fields. No resonant behavior occurs when the 2s state passes through the LO-phonon energy of 21 meV, but at higher fields of around 20 T, the resonances for both spin states (sigma(+/-)) of the 2s exciton broaden and show a strong anticrossing behavior. These experiments are shown to be in excellent agreement with a theoretical treatment which includes the resonant polaron coupling of the electrons alone. Both experiment and theory demonstrate an extremely strong resonant splitting of the 2s exciton states of approximately 11 meV, which is over 50% of the LO-phonon energy. The dominance of single-particle polaron coupling is attributed to the relative sizes of the polaron (35 Angstrom A) and the exciton (50 Angstrom A) radius.
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Impact Factor: 3.736
Times cited: 10
DOI: 10.1103/PhysRevB.50.7596
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“Interplay between s-d exchange interaction and Rashba effect: spin-polarized transport”. Yang W, Chang K, Wu XG, Zheng HZ, Peeters FM;, Applied physics letters 89 (2006). http://doi.org/10.1063/1.2357888
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.411
Times cited: 10
DOI: 10.1063/1.2357888
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“Inverse flux quantum periodicity of magnetoresistance oscillations in two-dimensional short-period surface superlattices”. Wang XF, Vasilopoulos P, Peeters FM, Physical review : B : condensed matter and materials physics 69, 035331 (2004). http://doi.org/10.1103/PhysRevB.69.035331
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 10
DOI: 10.1103/PhysRevB.69.035331
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“Kink-antikink vortex transfer in periodic-plus-random pinning potential : theoretical analysis and numerical experiments”. Pogosov WV, Zhao HJ, Misko VR, Peeters FM, Physical review : B : condensed matter and materials physics 81 (2010). http://doi.org/10.1103/PhysRevB.81.024513
Abstract: The influence of random pinning on the vortex dynamics in a periodic square potential under an external drive is investigated. Using numerical experiments and theoretical approach, we found several dynamical regimes of vortex motion that are different from the ones for a regular pinning potential. Vortex transfer is controlled by kinks and antikinks, which either pre-exist in the system or appear spontaneously in pairs and then propagate. When kinks and antikinks collide, they annihilate. We provide clear physical interpretations of the observed features.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 10
DOI: 10.1103/PhysRevB.81.024513
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“The local structure and composition of Ba4Nb2O9-based oxycarbonates”. Bezjak J, Abakumov AM, Recnik A, Krzmanc MM, Jancar B, Suvorov D, Journal of solid state chemistry 183, 1823 (2010). http://doi.org/10.1016/j.jssc.2010.06.003
Abstract: X-ray powder-diffraction(XRD),high-resolutiontransmissionelectronmicroscopy(HRTEM),electron diffraction(ED),infraredspectroscopy(IR),thermogravimetry(TG)andmassspectroscopy(MS)were performedtoinvestigatethecompositionandthecrystalstructureoftetra-bariumdi-niobate(V) Ba4Nb2O9. TheTG,MSandIRstudiesrevealedthatthecompoundisahydratedoxycarbonate.Assuming that thecarbonatestoichiometricallyreplacesoxygen,thecompositionofthelow-temperature a-modification,obtainedbyslowcoolingfrom1100 1C, correspondstoBa4Nb2O8.8(CO3)0.2 0.1H2O, while thequenchedhigh-temperature g-modificationhastheBa4Nb2O8.42(CO3)0.58 0.38H2O composi- tion. The a-phase hasacompositeincommensuratelymodulatedstructureconsistingoftwomutually interacting[Ba]N and the[(Nb,)O3]N subsystems.Thecompositemodulatedcrystalstructureofthe a-phase canbedescribedwiththelatticeparameters a¼10.2688(1) A˚ , c¼2.82426(8) A˚ , q¼0.66774(2)c* and asuperspacegroup R3m(00g)0s. TheHRTEManalysisdemonstratesthenanoscale twinningofthetrigonaldomainsparalleltothe{100}crystallographicplanes.Thetwinningintroduces a one-dimensionaldisorderintothe[(Nb,)O3]N subsystem,whichresultsinanaverage P62c crystal structureofthe a-phase. Possibleplacesforthecarbonategroupinthestructurearediscussedusinga comparisonwithotherhexagonalperovskite-basedoxycarbonates.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.299
Times cited: 10
DOI: 10.1016/j.jssc.2010.06.003
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“Long-wavelength, confined optical phonons in InAs nanowires probed by Raman spectroscopy”. Cantoro M, Klekachev AV, Nourbakhsh A, Sorée B, Heyns MM, de Gendt S, European physical journal : B : condensed matter and complex systems 79, 423 (2011). http://doi.org/10.1140/epjb/e2011-10705-2
Abstract: Strongly confined nano-systems, such as one-dimensional nanowires, feature deviations in their structural, electronic and optical properties from the corresponding bulk. In this work, we investigate the behavior of long-wavelength, optical phonons in vertical arrays of InAs nanowires by Raman spectroscopy. We attribute the main changes in the spectral features to thermal anharmonicity, due to temperature effects, and rule out the contribution of quantum confinement and Fano resonances. We also observe the appearance of surface optical modes, whose details allow for a quantitative, independent estimation of the nanowire diameter. The results shed light onto the mechanisms of lineshape change in low-dimensional InAs nanostructures, and are useful to help tailoring their electronic and vibrational properties for novel functionalities.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.461
Times cited: 10
DOI: 10.1140/epjb/e2011-10705-2
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“Low- or high-angle Ar ion-beam etching to create ramp-type Josephson junctions”. Verbist K, Lebedev OI, Van Tendeloo G, Verhoeven MAJ, Rijnders AJHM, Blank DHA, Superconductor science and technology 9, 978 (1996). http://doi.org/10.1088/0953-2048/9/11/009
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.325
Times cited: 10
DOI: 10.1088/0953-2048/9/11/009
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“Magnetoresistance in a hybrid ferromagnetic/semiconductor device”. Papp G, Peeters FM, Journal of applied physics 107, 063718 (2010). http://doi.org/10.1063/1.3359652
Abstract: Ballistic transport of a two-dimensional electron gas (2DEG) in a rectangle shaped wire, subjected to a local nonhomogeneous magnetic field that results from an in-plane magnetized ferromagnetic (FM) strip deposited above the 2DEG, is investigated theoretically. We found a positive magnetoresistance (MR), which exhibits hysteresis behavior with respect to the direction of the magnetic field sweep, in agreement with a recent experiment. This positive MR can be tuned by applying a gate voltage to the FM strip.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.068
Times cited: 10
DOI: 10.1063/1.3359652
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“Mechanical synthesis of high purity Cu-In-Se alloy nanopowder as precursor for printed CISe thin film solar cells”. Zaghi AE, Buffière M, Brammertz G, Batuk M, Lenaers N, Kniknie B, Hadermann J, Meuris M, Poortmans J, Vleugels J, Advanced powder technology 25, 1254 (2014). http://doi.org/10.1016/j.apt.2014.03.003
Abstract: Mechanical alloying and ball milling are low cost, up-scalable techniques for the preparation of high purity chalcogenide nanopowders to be used as precursor material for printing thin film solar cells. In this study, high purity copper indium selenium (Cu-In-Se) alloy nanopowders with 20-200 nm particle size were synthesized from macroscopic elemental Cu, In and Se powders via mechanical alloying and planetary ball milling. The particle size distribution, morphology, composition, and purity level of the synthesized Cu-In-Se alloy nanopowders were investigated. Thin Cu-In-Se alloy nanopowder ink coatings, deposited on Mo-coated glass substrates by doctor blading, were converted into a CuInSe2 semiconductor film by selenization heat treatment in Se vapor. The CuInSe2 film showed semiconducting band gap around 1 eV measured by photoluminescence spectroscopy. CuInSe2 absorber layer based thin film solar cell devices were fabricated to assess their performance. The solar cell device showed a total efficiency of 4.8%, as measured on 0.25 cm(2) area cell. (c) 2014 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.659
Times cited: 10
DOI: 10.1016/j.apt.2014.03.003
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“Melting of anisotropically confined Coulomb balls”. Apolinario SWS, Peeters FM, Physical review : B : condensed matter and materials physics 78, 024202 (2008). http://doi.org/10.1103/PhysRevB.78.024202
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 10
DOI: 10.1103/PhysRevB.78.024202
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“Microstructure and high temperature transport properties of high quality epitaxial SrFeO3-\delta films”. Solís C, Rossell MD, Garcia G, Figueras A, Van Tendeloo G, Santiso J, Solid state ionics 179, 1996 (2008). http://doi.org/10.1016/j.ssi.2008.06.004
Abstract: We report the high temperature electronic transport properties of SrFeO3 − ä epitaxial thin films obtained by pulsed laser deposition on NdGaO3(110) substrates. The films show total conductivity higher than the bulk material and apparent activation energy of about 0.12 eV in O2, lower than reported values for SrFeO3 − ä films. The conductivity dependence with oxygen partial pressure shows a power dependence with an exponent close to + 1/4, in agreement with expected point defect equilibrium. For a given oxygen partial pressure, the temperature coefficient of resistance (TCR) shows a low positive value of about 1.52.5 10− 3 K− 1, which is still suitable for resistive oxygen sensing applications. The transport properties of the films are discussed in view of their particular microstructure.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.354
Times cited: 10
DOI: 10.1016/j.ssi.2008.06.004
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“A new model for the (2x1) reconstructed CoSi2-Si(100) interface”. Buschmann V, Fedina L, Rodewald M, Van Tendeloo G, Philosophical magazine letters 77, 147 (1998). http://doi.org/10.1080/095008398178589
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 0.941
Times cited: 10
DOI: 10.1080/095008398178589
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“Observation of cyclotron resonance in an InAs/GaAs wetting layer with shallowly formed quantum dots”. Janssen G, Goovaerts E, Bouwen A, Partoens B, van Daele B, Zurauskiene N, Koenraad PM, Wolter JH, Physical review : B : condensed matter and materials physics 68, 045329 (2003). http://doi.org/10.1103/PhysRevB.68.045329
Keywords: A1 Journal article; Nanostructured and organic optical and electronic materials (NANOrOPT); Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 10
DOI: 10.1103/PhysRevB.68.045329
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“On the nature of ferromagnetism in dilute magnetic semiconductors : GaAs:Mn and GaP:Mn”. Ivanov VA, Krstajic PM, Peeters FM, Fleurov V, Kikoin K, Journal of magnetism and magnetic materials
T2 –, 2nd Moscow International Symposium on Magnetism (MISM 2001), JUN 20-24, 2001, MOSCOW STATE UNIV, MOSCOW, RUSSIA 258, 237 (2003). http://doi.org/10.1016/S0304-8853(02)01023-5
Abstract: On the basis of a simplified Hamiltonian for transition metal impurities in diluted magnetic semiconductors (DMS), the nature of ferromagnetism in p-type III-V DMS are investigated. Ferromagnetism is governed by the Anderson-Hubbard parameter for 3d electrons of Mn2+ and their strong hybridization with the hole carriers in the semiconducting medium. The origin of ferromagnetism in these materials has similarity with the Zener mechanism. From the energetically preferable parallel orientation of Mn spins the Curie temperature is calculated for GaAs:Mn. (C) 2002 Published by Elsevier Science B.V.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.63
Times cited: 10
DOI: 10.1016/S0304-8853(02)01023-5
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“Oscillating sliding wear of mono- and multilayer ceramic coatings in air”. Huq MZ, Celis JP, Meneve J, Stals L, Schryvers D, Surface and coatings technology 113, 242 (1999). http://doi.org/10.1016/S0257-8972(99)00009-2
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.589
Times cited: 10
DOI: 10.1016/S0257-8972(99)00009-2
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“Oscillating spin-orbit interaction in two-dimensional superlattices : sharp transmission resonances and time-dependent spin-polarized currents”. Szaszko-Bogar V, Peeters FM, Foeldi P, Physical review : B : condensed matter and materials physics 91, 235311 (2015). http://doi.org/10.1103/PhysRevB.91.235311
Abstract: We consider ballistic transport through a lateral, two-dimensional superlattice with experimentally realizable, sinusoidally oscillating, Rashba-type spin-orbit interaction (SOI). The periodic structure of the rectangular lattice produces a spin-dependent miniband structure for static SOI. Using Floquet theory, transmission peaks are shown to appear in themini-bandgaps as a consequence of the additional, time-dependent SOI. A detailed analysis shows that this effect is due to the generation of harmonics of the driving frequency, via which, e.g., resonances that cannot be excited in the case of static SOI become available. Additionally, the transmitted current shows space-and time-dependent partial spin polarization, in other words, polarization waves propagate through the superlattice.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 10
DOI: 10.1103/PhysRevB.91.235311
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“The polaron-bipolaron transition for acoustical three-dimensional polarons”. da Costa WB, Peeters FM, Journal of physics : condensed matter 8, 2173 (1996). http://doi.org/10.1088/0953-8984/8/13/009
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 2.346
Times cited: 10
DOI: 10.1088/0953-8984/8/13/009
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“Real space maps of magnetic moments on the atomic scale: theory and feasibility”. Schattschneider P, Ennen I, Stoger-Pollach M, Verbeeck J, Mauchamp V, Jaouen M, Ultramicroscopy 110, 1038 (2010). http://doi.org/10.1016/j.ultramic.2009.11.020
Abstract: The recently discovered EMCD technique (energy loss magnetic chiral dichroism) can detect atom specific magnetic moments with nanometer resolution, exploiting the spin selectivity of electronic transitions in energy loss spectroscopy. Yet, direct imaging of magnetic moments on the atomic scale is not possible. In this paper we present an extension of EMCD that can overcome this limit. As a model system we chose bcc Fe. We present image simulations of the L3 white line signal, based on the kinetic equation for the density matrix of the 200 kV probe electron. With actual progress in instrumentation (high brightness sources, aberration corrected lenses) this technique should allow direct imaging of spin moments on the atomic scale.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.843
Times cited: 10
DOI: 10.1016/j.ultramic.2009.11.020
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“Resistive switching at manganite/manganite interfaces”. Kalkert C, Krisponeit J-O, Esseling M, Lebedev OI, Moshnyaga V, Damaschke B, Van Tendeloo G, Samwer K, Applied physics letters 99, 132512 (2011). http://doi.org/10.1063/1.3643425
Abstract: We report bipolar resistive switching between the interfaces of manganite nanocolumns. La0.7Sr0.3MnO3 films were prepared on Al2O3 substrates, where the films grow in nanocolumns from the substrate to the surface. Conductive atomic force microscopy directly detects that the resistive switching is located at the boundaries of the grains. Furthermore, mesoscopic transport measurements reveal a tunnel magnetoresistance. In combination with the resistive switching, this leads to a total of four different resistive states.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.411
Times cited: 10
DOI: 10.1063/1.3643425
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“Spin-polarized transport of two-dimensional electron gas embedded in a diluted magnetic semiconductor”. Yang W, Chang K, Peeters FM, Applied physics letters 86, 192107 (2005). http://doi.org/10.1063/1.1927693
Abstract: The spin-polarized transport property of a diluted magnetic semiconductor two-dimensional electron gas is investigated theoretically at low temperature. A large current polarization can be found in this system even at small magnetic fields and oscillates with increasing magnetic field while the carrier polarization is vanishingly small. The magnitude as well as the sign of the current polarization can be tuned by varying magnetic field, the electron density and the Mn concentration. (c) 2005 American Institute of Physics.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.411
Times cited: 10
DOI: 10.1063/1.1927693
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“Spin transport through a ZnSe-based diluted magnetic semiconductor resonant tunneling structure in the presence of electric and magnetic fields”. Papp G, Borza S, Peeters FM, Physica status solidi B: basic solid state physics 243, 1956 (2006). http://doi.org/10.1002/pssb.200541504
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 1.674
Times cited: 10
DOI: 10.1002/pssb.200541504
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“Stability of multipolaron matter”. Smondyrev MA, Verbist G, Peeters FM, Devreese JT, Physical review : B : condensed matter and materials physics 47, 2596 (1993). http://doi.org/10.1103/PhysRevB.47.2596
Keywords: A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems
Impact Factor: 3.736
Times cited: 10
DOI: 10.1103/PhysRevB.47.2596
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“Structural and magnetic phase transitions in the AnBnO3n-2 anion-deficient perovskites Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16”. Abakumov AM, Batuk M, Tsirlin AA, Tyablikov OA, Sheptyakov DV, Filimonov DS, Pokholok KV, Zhidal VS, Rozova MG, Antipov EV, Hadermann J, Van Tendeloo G;, Inorganic chemistry 52, 7834 (2013). http://doi.org/10.1021/ic3026667
Abstract: Novel anion-deficient perovskite-based ferrites Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 were synthesized by solid-state reaction in air. Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 belong to the perovskite-based AnBnO3n2 homologous series with n = 5 and 6, respectively, with a unit cell related to the perovskite subcell ap as ap√2 × ap × nap√2. Their structures are derived from the perovskite one by slicing it with 1/2[110]p(1̅01)p crystallographic shear (CS) planes. The CS operation results in (1̅01)p-shaped perovskite blocks with a thickness of (n 2) FeO6 octahedra connected to each other through double chains of edge-sharing FeO5 distorted tetragonal pyramids which can adopt two distinct mirror-related configurations. Ordering of chains with a different configuration provides an extra level of structure complexity. Above T ≈ 750 K for Pb2Ba2BiFe5O13 and T ≈ 400 K for Pb1.5Ba2.5Bi2Fe6O16 the chains have a disordered arrangement. On cooling, a second-order structural phase transition to the ordered state occurs in both compounds. Symmetry changes upon phase transition are analyzed using a combination of superspace crystallography and group theory approach. Correlations between the chain ordering pattern and octahedral tilting in the perovskite blocks are discussed. Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 undergo a transition into an antiferromagnetically (AFM) ordered state, which is characterized by a G-type AFM ordering of the Fe magnetic moments within the perovskite blocks. The AFM perovskite blocks are stacked along the CS planes producing alternating FM and AFM-aligned FeFe pairs. In spite of the apparent frustration of the magnetic coupling between the perovskite blocks, all n = 4, 5, 6 AnFenO3n2 (A = Pb, Bi, Ba) feature robust antiferromagnetism with similar Néel temperatures of 623632 K.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 4.857
Times cited: 10
DOI: 10.1021/ic3026667
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“Structural features, oxygen and fluorine doping in Cu-based superconductors”. Antipov EV, Putilin SN, Shpanchenko RV, Alyoshin VA, Rozova MG, Abakumov AM, Mikhailova DA, Balagurov AM, Lebedev O, Van Tendeloo G, Physica: C : superconductivity
T2 –, International Conference on Materials and Mechanisms of, Superconductivity –, High Temperature Superconductors V, Feb. 28-Mar. 04, 1997, Beijing, Peoples R. China 282, 61 (1997). http://doi.org/10.1016/S0921-4534(97)00210-4
Abstract: The variation of structures and superconducting properties by changing extra oxygen or fluorine atoms concentration in Hg-based Cu mixed oxides and YBa2Cu3O6+delta was studied. The data obtained by NPD study of Hg-1201 can be considered as an evidence of the conventional oxygen doping mechanism with 2 delta holes per (CuO2) layer. The extra oxygen atom was found to be located in the middle of the Hg mesh only. Different formal charges of oxygen and fluorine inserted into reduced 123 structure results in its distinct variations. The fluorine incorporation into strongly reduced YBa2Cu3O6+delta causes a significant structural rearrangement and the formation of a new compound with a composition close to YBa2Cu3O6F2 (tetragonal alpha = 3.87 Angstrom and c approximate to 13 Angstrom), which structure was deduced from the combined results of X-ray diffraction, electron diffraction and high resolution electron microscopy. Fluorination treatment by XeF2 of nonsuperconducting 123 samples causes an appearance of bulk superconductivity with T-c up to 94K.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.404
Times cited: 10
DOI: 10.1016/S0921-4534(97)00210-4
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“Synchronized dynamics of Josephson vortices in artificial stacks of SNS Josephson junctions under both dc and ac bias currents”. Berdiyorov GR, Savel'ev SE, Milošević, MV, Kusmartsev FV, Peeters FM, Physical review : B : condensed matter and materials physics 87, 184510 (2013). http://doi.org/10.1103/PhysRevB.87.184510
Abstract: Nonlinear dynamics of Josephson vortices (fluxons) in artificial stacks of superconducting-normal-superconducting Josephson junctions under simultaneously applied time-periodic ac and constant biasing dc currents is studied using the time dependent Ginzburg-Landau formalism with a Lawrence-Doniach extension. At zero external magnetic field and dc biasing current the resistive state of the system is characterized by periodic nucleation and annihilation of fluxon-antifluxon pairs, relative positions of which are determined by the state of neighboring junctions. Due to the mutual repulsive interaction, fluxons in different junctions move out of phase. Their collective motion can be synchronized by adding a small ac component to the biasing dc current. Coherent motion of fluxons is observed for a broad frequency range of the applied drive. In the coherent state the maximal output voltage, which is proportional to the number of junctions in the stack, is observed near the characteristic frequency of the system determined by the crossing of the fluxons across the sample. However, in this frequency range the dynamically synchronized state has an alternative-a less ordered state with smaller amplitude of the output voltage. Collective behavior of the junctions is strongly affected by the sloped sidewalls of the stack. Synchronization is observed only for weakly trapezoidal cross sections, whereas irregular motion of fluxons is observed for larger slopes of the sample edge.
Keywords: A1 Journal article; Condensed Matter Theory (CMT)
Impact Factor: 3.836
Times cited: 10
DOI: 10.1103/PhysRevB.87.184510
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