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“A study of the domain structure of epitaxial (La-Ca)MnO3 films by high-resolution transmission electron microscopy”. Lebedev OI, Van Tendeloo G, Abakumov AM, Amelinckx S, Leibold B, Habermeier H-U, Philosophical magazine: A: physics of condensed matter: defects and mechanical properties 79, 1461 (1999). http://doi.org/10.1080/01418619908210372
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 27
DOI: 10.1080/01418619908210372
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“Room temperature and low-temperature structure of Nd1-xCaxMnO3 (0.3*x*0.5)”. Richard O, Schuddinck W, Van Tendeloo G, Millange F, Hervieu M, Caignaert C, Raveau B, Acta crystallographica: section A: foundations of crystallography 55, 704 (1999). http://doi.org/10.1107/S0108767398012215
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 5.725
Times cited: 24
DOI: 10.1107/S0108767398012215
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“A homologous series Pb2n+1Nb2n-1O7n-1 studied by electron microscopy”. Leroux C, Badeche T, Nihoul G, Richard O, Van Tendeloo G, European physical journal: applied physics 7, 33 (1999). http://doi.org/10.1051/epjap:1999196
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 0.684
Times cited: 4
DOI: 10.1051/epjap:1999196
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“Synthesis of single wall carbon nanotubes by catalytic decomposition of hydrocarbons”. Colomer J-F, Bister G, Willems I, Konya Z, Fonseca A, Van Tendeloo G, Nagy JB, Chemical communications , 1343 (1999). http://doi.org/10.1039/a903142a
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 6.319
Times cited: 110
DOI: 10.1039/a903142a
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“Charge ordering-disordering in Th-doped CaMnO3”. Hervieu M, Martin C, Maignan A, Van Tendeloo G, Raveau B, European physical journal : B : condensed matter and complex systems 10, 397 (1999). http://doi.org/10.1007/s100510050869
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.461
Times cited: 6
DOI: 10.1007/s100510050869
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“The phase transition and crystal structures of Ba3RM2O7.5 complex oxides (R=rare-earth elements, M = Al,Ga)”. Abakumov AM, Shpanchenko RV, Lebedev OI, Van Tendeloo G, Amelinckx S, Antipov EV, Acta crystallographica: section A: foundations of crystallography 55, 828 (1999). http://doi.org/10.1107/S0108767399002068
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 5.725
Times cited: 7
DOI: 10.1107/S0108767399002068
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“Phase competition between Y2BaCuO5 and Y2O3 precipitates in Y-rich YBCO thin films”. Scotti di Uccio U, Miletto Granozio F, di Chiara A, Tafuri F, Lebedev OI, Verbist K, Van Tendeloo G, Physica: C : superconductivity 321, 162 (1999)
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.404
Times cited: 17
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“Preparation of nanocrystalline titania powder via aerosol pyrolysis of titanium tetrabutoxide”. Ahonen PP, Kauppinen EI, Joubert JC, Deschanvres JL, Van Tendeloo G, Journal of materials research 14, 3938 (1999). http://doi.org/10.1557/JMR.1999.0533
Abstract: Nanocrystalline titanium dioxide was prepared via aerosol pyrolysis of titanium alkoxide precursor at 200-580 degrees C in air and in nitrogen atmospheres. Powders were characterized by x-ray diffraction, thermogravimetric analysis, Brunauer-Emmett-Teller analysis, scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy, x-ray fluorescence, Raman and infrared spectroscopy, and Berner-type low-pressure impactor. The anatase phase transition was initiated at 500 degrees C in nitrogen and at 580 degrees C in air. Under other conditions amorphous powders were observed and transformed to nanocrystalline TiO2 via thermal postannealing. In air, smooth and spherical particles with 2-4-mu m diameter were formed with an as-expected tendency to convert to rutile in the thermal postannealings. In nitrogen, a fraction of the titanium tetrabutoxide precursor evaporated and formed ultrafine particles via the gas-to-particle conversion. At 500 degrees C thermally stable anatase phase was formed in nitrogen. A specific surface area as high as 280 m(2) g(-1) was observed for an as-prepared powder.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.673
Times cited: 38
DOI: 10.1557/JMR.1999.0533
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“_Fe2O3 nanoparticles with mesoporous MCM-48 silica: in situ formation and characterisation”. Fröba M, Köhn R, Bouffaud G, Richard O, Van Tendeloo G, Chemistry of materials 11, 2858 (1999). http://doi.org/10.1021/cm991048i
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 9.466
Times cited: 202
DOI: 10.1021/cm991048i
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“Microstructure and properties of oxygen controlled melt textured NdBaCuO superconductive ceramics”. Monot I, Tancret F, Laffez P, Van Tendeloo G, Desgardin G, Technology 65, 26 (1999). http://doi.org/10.1016/S0921-5107(99)00193-2
Abstract: Nd1+xBa2-xCu3O7-delta (123) bulk superconductors have been synthesised by the oxygen controlled melt growth method. Unlike the YBaCuO system, platinum doping or Nd4Ba2Cu2O10 (422) rich compositions do not refine the peritectic '422' secondary phase, but the latter improves the microstructural quality. Low oxygen partial pressure and high purity precursors are necessary to achieve in a reproducible manner high T-c and J(c) (up to 56 000 A/cm(2) in 0T and 30 000 A/cm(2) under 1.5T). The fishtail effect observed at 77 K is compared with the one observed in the YBCO system, and is discussed in terms of oxygen deficiency, Nd-Ba substitution, defects and vortex lattice. Our TEM observations did not evidence any Nd-Ba substituted clusters in the Nd123 matrix; however, some diffuse streaks, observed in the [100] zone ED pattern, support the fact that the source of the peak effect in this system is mainly due to oxygen disorder and low stability of the orthorhombic phase. (C) 1999 Elsevier Science S.A. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.552
Times cited: 5
DOI: 10.1016/S0921-5107(99)00193-2
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“Structural transformations in the fluorinated T* phase”. Hadermann J, Abakumov AM, Lebedev OI, Van Tendeloo G, Rozova MG, Shpanchenko RV, Pavljuk BP, Kopnin EM, Antipov EV, Journal of solid state chemistry 147, 647 (1999). http://doi.org/10.1006/jssc.1999.8438
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.299
Times cited: 8
DOI: 10.1006/jssc.1999.8438
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“YBa2Cu3O7-x Josephson junctions and dc SQUIDs based on 45\text{\textdegree} a-axis tilt and twist grain boundaries : atomically clean interfaces for applications”. Tafuri F, Carillo F, Lombardi F, Granozio FM, dii Uccio US, Testa G, Sarnelli E, Verbist K, Van Tendeloo G, Superconductor science and technology
T2 –, International Superconductive Electronics Conference, JUN 21-25, 1999, BERKELEY, CALIFORNIA 12, 1007 (1999). http://doi.org/10.1088/0953-2048/12/11/393
Abstract: YBa2Cu3O7-x artificial grain boundary Josephson junctions have been fabricated, employing a recently implemented biepitaxial technique. The grain boundaries can be obtained by controlling the orientation of the MgO seed layer and are characterized by a misalignment of the c-axes (45 degrees a-axis tilt or 45 degrees a-axis twist). These types of grain boundaries are still mostly unexplored. We carried out a complete characterization of their transport properties and microstructure. Junctions and de SQUIDs associated with these grain boundaries exhibit an excellent Josephson phenomenology and high values of the ICRN product and of the magnetic flux-to-voltage transfer parameter respectively. Remarkable differences in the transport parameters of tilt and twist junctions have been observed, which can be of interest for several applications. A maximum speed of Josephson vortices as calculated from the voltage step values of the order of 2 x 10(6) m s(-1) is obtained. These devices could also have some impact on experiments designed to study the symmetry of the order parameter, exploiting their microstructure and anisotropic properties. High-resolution electron microscopy showed the presence of perfect basal plane faced boundaries in the cross sections of tilt boundaries.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.878
Times cited: 3
DOI: 10.1088/0953-2048/12/11/393
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“Mobility collapse in undoped and Si-doped GaN grown by LP-MOVPE”. Bougrioua Z, Farvacque J-L, Moerman I, Demeester P, Harris JJ, Lee K, Van Tendeloo G, Lebedev O, Trush EJ, Physica status solidi: B: basic research 216, 571 (1999). http://doi.org/10.1002/(SICI)1521-3951(199911)216:1<571::AID-PSSB571>3.0.CO;2-K
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.674
Times cited: 13
DOI: 10.1002/(SICI)1521-3951(199911)216:1<571::AID-PSSB571>3.0.CO;2-K
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“Structural determination of the charge ordering process in Nd0.5Ca0.5Mn1-xCrxO3 manganites”. Schuddinck W, Van Tendeloo G, Barnabé, A, Hervieu M, Raveau B, Journal of solid state chemistry 148, 333 (1999). http://doi.org/10.1006/jssc.1999.8457
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.299
Times cited: 12
DOI: 10.1006/jssc.1999.8457
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“Josephson phenomenology and microstructure of YBaCuO artificial grain boundaries characterized by misalignment of the c-axes”. Tafuri F, Granozio FM, Carillo F, Lombardi F, Di Uccio US, Verbist K, Lebedev O, Van Tendeloo G, Physica: C : superconductivity 327, 63 (1999). http://doi.org/10.1016/S0921-4534(99)00372-X
Abstract: YBa(2)Cu(3)O(7-delta) (YBCO) grain boundaries characterized by a misalignment of the c-axes (45 degrees c-axis tilt or 45 degrees c-axis twist) have been obtained by employing a recently implemented biepitaxial technique. Junctions based on these grain boundaries exhibit good Josephson properties useful for applications. High values of the I(C)R(N) product and a Fraunhofer-like dependence of the critical current on the magnetic field, differently from traditional biepitaxial junctions, have been obtained. The correlation between transport properties and microstructure has been investigated by Transmission Electron Microscopy (TEM), which was also performed on previously measured junctions. The presence of atomically clean basal plane (BP) faced tilt boundaries, among other types of interfaces, has been shown. The possibility of selecting these kinds of boundaries by controlling film growth, and their possible advantages in terms of reproducibility and uniformity of the junction properties an discussed. The possibility of employing these junctions to explore the symmetry of the order parameter is also discussed. (C) 1999 Elsevier Science B.V. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.404
Times cited: 7
DOI: 10.1016/S0921-4534(99)00372-X
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“Production of differently shaped multi-wall carbon nanotubes using various cobalt supported catalysts”. Piedigrosso P, Konya Z, Colomer J-F, Fonseca A, Van Tendeloo G, Nagy JB, Physical chemistry, chemical physics 2, 163 (2000). http://doi.org/10.1039/a905622j
Abstract: Catalytic synthesis and transmission electron microscopy (TEM) of multi-wall carbon nanotubes are presented. Silica, zeolite and alumina supported cobalt catalysts were prepared by different methods (impregnation and ion-adsorption precipitation) and were used to produce nanotubes. The synthesis was carried out in a fixed bed flow reactor and the process was optimized in order to produce carbon nanotubes on a gram scale. The influence of various parameters such as the method of catalyst preparation, the nature of the support, cobalt concentration and reaction conditions on the formation of nanotubes was investigated. The carbon deposits were measured and the quality of nanotubes was determined by low and high resolution TEM. Multi-wall straight and coiled nanotubes were found to be fairly regular with an average inner (outer) diameter of 4-7 nm (8-23 nm) and with lengths up to 0.1 mm.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 4.123
Times cited: 53
DOI: 10.1039/a905622j
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“Role of the defect microstructure on the electrical transport properties in undoped and Si-doped GaN grown by LP-MOVPE”. Farvacque JL, Bougrioua Z, Moerman I, Van Tendeloo G, Lebedev O, Physica: B : condensed matter
T2 –, 20th International Conference on Defects in Semiconductors (ICDS-20), JUL 26-30, 1999, BERKELEY, CA 273-4, 140 (1999). http://doi.org/10.1016/S0921-4526(99)00431-7
Abstract: Experimental results show that the room-temperature carrier mobility in bulk layers of undoped or Si-doped GaN grown by LP-MOVPE on sapphire substrate shows a sudden increase as soon as the carrier density exceeds a critical value of about 10(18) cm(-3). We show that such a behavior can be theoretically reproduced by assuming that the columnar structure i.e. the dislocation microstructure is responsible for internal electronic barriers. (C) 1999 Elsevier Science B.V. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.386
Times cited: 5
DOI: 10.1016/S0921-4526(99)00431-7
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“Epitaxial strain induced metal insulator transition in La0.9Sr0.1MnO3 and La0.88Sr0.1MnO3 thin films”. Razavi FS, Gross G, Habermeier H-U, Lebedev O, Amelinckx S, Van Tendeloo G, Vigliante A, Applied physics letters 76, 155 (2000). http://doi.org/10.1063/1.125687
Abstract: We are reporting an unexpected metal insulator transition at the ferromagnetic phase-transition temperature for thin films of La0.9Sr0.1MnO3 (< 50 nm), grown on a (100) face of SrTiO3 substrate. For the thicker films (> 50 nm), similar to the single crystal, no such transition is observed below T-C. Additionally, we observe the suppression of the features associated with charge or orbital ordering in intentionally La-deficient thin films of La0.88Sr0.1MnO3 (< 75 nm). In thin films, transmission electron microscopy reveals a compressive strain due to the epitaxial growth, that is, lattice parameters adopt those of the cubic lattice of SrTiO3. As the film thickness increases, coherent microtwinning is observed in the films and the films relax to a orthorhombic structure. (C) 2000 American Institute of Physics. [S0003-6951(00)00402-2].
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.411
Times cited: 91
DOI: 10.1063/1.125687
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“Size mismatch : a crucial factor for generating a spin-glass insulator in manganites”. Maignan A, Martin C, Van Tendeloo G, Hervieu M, Raveau B, Physical review : B : condensed matter and materials physics 60, 15214 (1999). http://doi.org/10.1103/PhysRevB.60.15214
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].
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 75
DOI: 10.1103/PhysRevB.60.15214
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“Microstructure and Josephson phenomenology in 45°, tilt and twist Yba2Cu3o7-\delta artificial grain boundaries”. Tafuri F, Miletto Granozio F, Carillo F, di Chiara A, Verbist K, Van Tendeloo G, Physical review : B : condensed matter and materials physics 59, 11523 (1999). http://doi.org/10.1103/PhysRevB.59.11523
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 52
DOI: 10.1103/PhysRevB.59.11523
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“Control of the outer diameter of thin carbon nanotubes synthesized by catalytic decomposition of hydrocarbons”. Willems I, Konya Z, Colomer JF, Van Tendeloo G, Nagaraju N, Fonseca A, Nagy JB, Chemical physics letters 317, 71 (2000). http://doi.org/10.1016/S0009-2614(99)01300-7
Abstract: Multi-wall carbon nanotubes have been produced by the catalytic decomposition of acetylene. Go-Mo, Co-V and Co-Fe mixtures supported either on zeolite or corundum alumina were used as catalysts. When Fe or V is added to Co, the carbon deposit increases. The nanotubes were characterized by both low and high resolution TEM. From histograms representing the outer diameter distributions, it is clear that the outer diameter of the nanotubes can be controlled by choosing the appropriate catalyst. (C) 2000 Elsevier Science B.V. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.815
Times cited: 130
DOI: 10.1016/S0009-2614(99)01300-7
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“Large-scale synthesis of single-wall carbon nanotubes by catalytic chemical vapor deposition (CCVD) method”. Colomer JF, Stephan C, Lefrant S, Van Tendeloo G, Willems I, Konya Z, Fonseca A, Laurent C, Nagy JB, Chemical physics letters 317, 83 (2000). http://doi.org/10.1016/S0009-2614(99)01338-X
Abstract: The large-scale production of single-wall carbon nanotubes (SWNTs) is reported. Large quantities of SWNTs can be synthesised by catalytic decomposition of methane over well-dispersed metal particles supported on MgO at 1000 degrees C. The thus produced SWNTs can be separated easily from the support by a simple acidic treatment to obtain a product with high yields (70-80%) of SWNTs. Because the typical synthesis time is 10 min, 1 g of SWNTs can be synthesised per day by this method. The SWNTs are characterized by high-resolution transmission electron microscopy and by Raman spectroscopy, showing the quality and the quantity of products. (C) 2000 Elsevier Science B.V. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.815
Times cited: 344
DOI: 10.1016/S0009-2614(99)01338-X
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“Microstructure and phase transitions in Pb(Sc0.5Ta0.5)O3”. Lemmens H, Richard O, Van Tendeloo G, Bismayer U, Journal of electron microscopy 48, 843 (1999). http://doi.org/10.1093/oxfordjournals.jmicro.a023756
Abstract: The microstructure and phase transitions in the perovskite-based ferroelectric lead scandium tantalate, Pb(Sc0.5Ta0.5)O-3 have been investigated by transmission electron microscopy. The effects of ordering of Sc and Ta cations are apparent in reciprocal space as well as in direct space images. High-resolution observations allow direct structure imaging of the domain structure. The structure of the low temperature ferroelectric phase is studied by selected area electron diffraction (SAED) and electron microdiffraction. The relaxer behaviour of this paraelectric-ferroelectric transition is displayed by diffuse intensities in the SAED patterns at temperatures around the Curie point.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 0.9
Times cited: 7
DOI: 10.1093/oxfordjournals.jmicro.a023756
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“Synthesis and crystal structure of a new complex oxyfluoride La0.813Sr0.187Cu(o,F)3-\delta”. Abakumov AM, Hadermann J, Rozova MG, Pavljuk BP, Antipov EV, Lebedev OI, Van Tendeloo G, Journal of solid state cemistry 149, 189 (2000). http://doi.org/10.1006/jssc.1999.8521
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.299
Times cited: 8
DOI: 10.1006/jssc.1999.8521
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“Atomic and microstructure of CMR materials”. Van Tendeloo G, Lebedev OI, Amelinckx S, Journal of magnetism and magnetic materials 211, 73 (2000). http://doi.org/10.1016/S0304-8853(99)00716-7
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.63
Times cited: 48
DOI: 10.1016/S0304-8853(99)00716-7
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“Relation between structure, charge ordering and magnetotransport properties in Nd0.5Ca0.5Mn1-xCrxO3 manganites”. Schuddinck W, Van Tendeloo G, Barnabé, A, Hervieu M, Raveau B, Journal of magnetism and magnetic materials
T2 –, Symposium G Material Physics Issues and Applications of Magnetic Oxides, at the E-MRS Spring Meeting, JUN 01-04, 1999, Strasbourg, France 211, 105 (2000). http://doi.org/10.1016/S0304-8853(99)00720-9
Abstract: The relationships between incommensurability, charge ordering and magnetotransport properties in Nd0.5Ca0.5Mn1-xCrxO3 manganites have been studied by electron diffraction and lattice imaging versus temperature with 0.02 less than or equal to x less than or equal to 0.07. All compositions show an incommensurate superstructure over the whole temperature domain, despite the fact that they are ferromagnetic and conductive below 140 K, The q-vector (1/2 – delta)a* decreases with increasing temperature for all compositions x. For a given temperature q also decreases with x. Lattice images obtained at low temperature give a clear view of the characteristics of the incommensurate structure. They also provide a better understanding of the charge ordering process. The low-temperature form of the Cr-doped manganites is not a perfectly doubled cell [[2a(p)root 2 x 2a(p) x a(p)root 2]], but defects inducing a tripled cell occur pseudo-periodically. (C) 2000 Elsevier Science B.V. All rights reserved.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 2.63
Times cited: 16
DOI: 10.1016/S0304-8853(99)00720-9
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“High-resolution electron microscopy study of strained epitaxial La0.7Sr0.3MnO3 thin films”. Lebedev OI, Van Tendeloo G, Amelinckx S, Ju HL, Krishnan KM, Philosophical magazine: A: physics of condensed matter: defects and mechanical properties 80, 673 (2000). http://doi.org/10.1080/01418610008212075
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Times cited: 52
DOI: 10.1080/01418610008212075
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“Structural and magnetic properties of the colossal magnetoresistance perovskite La0.85Ca0.15MnO3”. Lobanov MV, Balagurov AM, Pomjakushin VJ, Fischer P, Gutmann M, Abakumov AM, D'yachenko OG, Antipov EV, Lebedev OI, Van Tendeloo G, Physical review : B : condensed matter and materials physics 61, 8941 (2000). http://doi.org/10.1103/PhysRevB.61.8941
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 47
DOI: 10.1103/PhysRevB.61.8941
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“In situ HREM irradiation study of point-defect clustering in MBE-grown strained Si1-xGex/(001)Si structures”. Fedina L, Lebedev OI, Van Tendeloo G, van Landuyt J, Mironov OA, Parker EHC, Physical review : B : condensed matter and materials physics 61, 10336 (2000). http://doi.org/10.1103/PhysRevB.61.10336
Abstract: We present a detailed analysis of the point-defect clustering in strained Si/Si(1-x)Ge(x)/(001)Si structures, including the interaction of the point defects with the strained interfaces and the sample surface during 400 kV electron irradiation at room temperature. Point-defect cluster formation is very sensitive to the type and magnitude of the strain in the Si and Si(1-x)Ge(x) layers. A small compressive strain (-0.3%) in the SiGe alloy causes an aggregation of vacancies in the form of metastable [110]-oriented chains. They are located on {113} planes and further recombine with interstitials. Tensile strain in the Si layer causes an aggregation of interstitial atoms in the forms of additional [110] rows which are inserted on {113} planes with [001]-split configurations. The chainlike configurations are characterized by a large outward lattice relaxation for interstitial rows (0.13 +/-0.01 nm) and a very small inward relaxation for vacancy chains (0.02+/-0.01 nm). A compressive strain higher than -0.5% strongly decreases point-defect generation inside the strained SiGe alloy due to the large positive value of the formation volume of a Frenkel pair. This leads to the suppression of point-defect clustering in a strained SiGe alloy so that SiGe relaxes via a diffusion of vacancies from the Si layer, giving rise to an intermixing at the Si/SiGe interface. In material with a 0.9% misfit a strongly increased flow of vacancies from the Si layer to the SiGe layer and an increased biaxial strain in SiGe bath promote the preferential aggregation of vacancies in the (001) plane, which relaxes to form intrinsic 60 degrees dislocation loops.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.836
Times cited: 27
DOI: 10.1103/PhysRevB.61.10336
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“Ferroelastic orientation states and domain walls in lead phosphate type crystals”. Bismayer U, Mathes D, Bosbach D, Putnis A, Van Tendeloo G, Novak J, Salje EKH, Mineralogical magazine 64, 233 (2000). http://doi.org/10.1180/002646100549328
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 1.285
Times cited: 16
DOI: 10.1180/002646100549328
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