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Author Vincze, L.; Vekemans, B.; Janssens, K.; Adams, F.
Title Modeling of photon scattering at high X-ray energies : experiment versus simulation Type A1 Journal article
Year 1999 Publication Journal of analytical atomic spectrometry T2 – 15th International Congress on X-Ray Optics and Microanalysis (ICXOM), AUG 24-27, 1998, ANTWERP, BELGIUM Abbreviated Journal J Anal Atom Spectrom
Volume 14 Issue 3 Pages 529-533
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The use of a detailed Monte Carlo simulation code for X-ray fluorescence spectrometers is demonstrated for calculating the outcome of X-ray scattering experiments in the incident energy range 40-80 keV. The code was validated by comparisons of experimental and simulated spectral distributions in the case of thick, homogeneous samples in which multiple photon scattering occurs with high probability. The experimental spectral distributions were collected at beamline BW5 of HASYLAB, Germany, where a highly energetic, monochromatic synchrotron beam is available. With respect to heterogeneous samples, the code was employed to evaluate the use of Rayleigh and Compton scatter signals for obtaining three dimensional information on the sample dark matrix composition.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000079138500032 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0267-9477 ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.379 Times cited Open Access
Notes Approved Most recent IF: 3.379; 1999 IF: 3.677
Call Number UA @ admin @ c:irua:103504 Serial 5732
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Author Habermeier, H.U.; Razavi, F.; Lebedev, O.; Gross, G.M.; Praus, R.; Zhang, P.X.
Title Correlation of microstructure and magnetotransport properties of epitaxially grown La-Ca-Mn-O3 thin films Type A1 Journal article
Year 1999 Publication Physica status solidi: B: basic research T2 – International Conference on Solid State Spectroscopy – (ICSSS), SEP 05-07, 1999, SCHWABISCH-GMUND, GERMANY Abbreviated Journal Phys Status Solidi B
Volume 215 Issue 1 Pages 679-683
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We have investigated epitaxially grown single-crystalline Ca-doped LaMnO3 thin films using the pulsed laser deposition technique in a case study aimed to explore the possibilities buried in epitaxial stress tailoring in order to control the transport properties of CMR materials beyond the limits set by equilibrium thermodynamics. Depending on the film thickness there is an abrupt transition from pseudomorphic to epitaxial granular growth observable which is related to the epitaxial strain of the films. This is associated with microscopic stress relaxation and leads to well controllable modifications of the atomic arrangements of the Mn-O sublattice in the films. Due to the interrelation of double exchange, spin-, charge- and orbital ordering and the Jahn-Teller effect mediated coupling of the electronic system to the crystal lattice, the magnetotransport properties of the firms can be modified in a controllable way.
Address
Corporate Author Thesis
Publisher Place of Publication Berlin Editor
Language Wos 000082487800110 Publication Date 2002-09-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-1972;1521-3951; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.674 Times cited 3 Open Access
Notes Approved Most recent IF: 1.674; 1999 IF: 0.978
Call Number UA @ lucian @ c:irua:103489 Serial 527
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Author de Gryse, O.; Clauws, P.; Rossou, L.; van Landuyt, J.; Vanhellemont, J.
Title Accurate infrared spectroscopy determination of interstitial and precipitated oxygen in highly doped Czochralski-grown silicon Type A1 Journal article
Year 1999 Publication The review of scientific instruments Abbreviated Journal Rev Sci Instrum
Volume 70 Issue 9 Pages 3661-3663
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A method has been developed to determine the interstitial and precipitated oxygen concentration in highly doped n- and p-type silicon. 10-30-mu m-thin silicon samples in a mechanical stress-free state and without alteration of the thermal history are prepared and measured with Fourier transform infrared spectroscopy at 5.5-6 K. The measured oxygen contents in the as-grown Si samples agree well with those obtained with gas fusion analysis. In the highly boron-doped samples, the interstitial oxygen can be determined down to 10(17) cm(-3). (C) 1999 American Institute of Physics. [S0034-6748(99)04909-6].
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000082289200026 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0034-6748; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.515 Times cited 5 Open Access
Notes Approved Most recent IF: 1.515; 1999 IF: 1.293
Call Number UA @ lucian @ c:irua:103487 Serial 48
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Author Ahonen, P.P.; Kauppinen, E.I.; Joubert, J.C.; Deschanvres, J.L.; Van Tendeloo, G.
Title Preparation of nanocrystalline titania powder via aerosol pyrolysis of titanium tetrabutoxide Type A1 Journal article
Year 1999 Publication Journal of materials research Abbreviated Journal J Mater Res
Volume 14 Issue 10 Pages 3938-3948
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
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.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000083163700019 Publication Date 2008-03-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0884-2914;2044-5326; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.673 Times cited 38 Open Access
Notes Approved Most recent IF: 1.673; 1999 IF: 1.574
Call Number UA @ lucian @ c:irua:103485 Serial 2705
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Author Bussmann-Holder, A.; Dalal, N.; Michel, K.H.
Title Polarizability induced cooperative proton ordering, coexistence of order/disorder and displacive dynamics and isotope effects in hydrogen-bonded systems Type A1 Journal article
Year 2000 Publication The journal of physics and chemistry of solids T2 – Williamsburg Workshop on Ferroelectrics 99, JAN 31-FEB 03, 1999, WILLIAMSBURG, VIRGINIA Abbreviated Journal J Phys Chem Solids
Volume 61 Issue 2 Pages 271-274
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Despite the general belief that hydrogen-bonded ferro- and antiferroelectrics undergo a pure order/disorder transition at the structural instability, new NMR data and a new theoretical concept yield convincing evidence that a pronounced displacive component is present in these systems, which modifies substantially the temperature dependencies of the tunnel and lattice mode frequencies. The experiments and their interpretation are presented. (C) 1999 Elsevier Science Ltd. All rights reserved.
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Corporate Author Thesis
Publisher Pergamon-elsevier science ltd Place of Publication Oxford Editor
Language Wos 000084147000020 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-3697; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.059 Times cited 8 Open Access
Notes Approved Most recent IF: 2.059; 2000 IF: 1.003
Call Number UA @ lucian @ c:irua:103469 Serial 2660
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Author Riva, C.; Peeters, F.M.; Varga, K.
Title Ground state of excitons and charged excitons in a quantum well Type A1 Journal article
Year 2000 Publication Physica status solidi: A: applied research T2 – 6th International Conference on Optics of Excitons in Confined Systems, (OECS-6), AUG 30-SEP 02, 1999, ASCONA, SWITZERLAND Abbreviated Journal Phys Status Solidi A
Volume 178 Issue 1 Pages 513-517
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract A variational calculation of the ground state of a neutral exciton and of positively and negatively charged excitons (trions) in a single quantum well is presented. We study the dependence of the correlation energy and of the binding energy on the well width and on the hole mass. Our results are compared with previous theoretical results and with available experimental data.
Address
Corporate Author Thesis
Publisher Place of Publication Berlin Editor
Language Wos 000086440500089 Publication Date 2002-09-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0031-8965;1521-396X; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 16 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:103467 Serial 1389
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Author Fedina, L.; Lebedev, O.I.; Van Tendeloo, G.; van Landuyt, J.; Mironov, O.A.; Parker, E.H.C.
Title In situ HREM irradiation study of point-defect clustering in MBE-grown strained Si1-xGex/(001)Si structures Type A1 Journal article
Year 2000 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 61 Issue 15 Pages 10336-10345
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
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.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000086606200082 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 27 Open Access
Notes Conference Name: Microsc. Semicond. Mater. Conf. Approved Most recent IF: 3.836; 2000 IF: NA
Call Number UA @ lucian @ c:irua:103456 Serial 1577
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Author Hervieu, M.; Martin, C.; Maignan, A.; Van Tendeloo, G.; Jirak, Z.; Hejtmanek, J.; Barnabe, A.; Thopart, D.; Raveau, B.
Title Structural and magnetotransport transitions in the electron-doped Pr1-xSrxMnO3(0.85\leq x\leq1) manganites Type A1 Journal article
Year 2000 Publication Chemistry and materials Abbreviated Journal Chem Mater
Volume 12 Issue 5 Pages 1456-1462
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The exploration of the Mn4+-rich side of the Pr1-xSrxMnO3 system has allowed the extension of the domain of the cubic perovskite, by using a two-step process, combining synthesis under Ar flow at high temperature and O-2 pressure annealing at lower temperature. We show that these Pr-doped cubic perovskites exhibit a coupled structural (cubic-tetragonal) and magnetic (para-antiferro) transition connected with a resistivity jump at the same temperature. The strong interplay between lattice, charges, and spins for these oxides results from the appearance at low temperature of the distorted C-type antiferromagnetic structure. The Pr1-xSrxMnO3 magnetic phase diagram shows, for 0.9 less than or equal to x less than or equal to 1 (i.e., on the Mn4+-rich side), the existence at low temperature of C- and G-type antiferromagnetism. The absence of ferromagnetic-antiferromagnetic competition explains that magnetoresistante properties are not observed in this system, in contrast to Mn4+-rich Ln(1-x)Ca(x)MnO(3) systems.
Address
Corporate Author Thesis
Publisher Place of Publication Washington, D.C. Editor
Language Wos 000087136800039 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0897-4756;1520-5002; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 9.466 Times cited 24 Open Access
Notes Approved Most recent IF: 9.466; 2000 IF: 3.580
Call Number UA @ lucian @ c:irua:103454 Serial 3198
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Author Nistor, L.; Bender, H.; Vantomme, A.; Wu, M.F.; van Landuyt, J.; O'Donnell, K.P.; Martin, R.; Jacobs, K.; Moerman, I.
Title Direct evidence of spontaneous quantum dot formation in a thick InGaN epilayer Type A1 Journal article
Year 2000 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 77 Issue 4 Pages 507-509
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report a direct observation of quantum dots formed spontaneously in a thick InGaN epilayer by high resolution transmission electron microscopy. Investigation of a (280 nm thick) In0.22Ga0.78N single layer, emitting in the blue/green spectral region, reveals quantum dots with estimated sizes in the range of 1.5-3 nm. Such sizes are in very good agreement with calculations based on the luminescence spectra of this specimen. (C) 2000 American Institute of Physics. [S0003-6951(00)00930-X].
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000088225400016 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0003-6951; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.411 Times cited 44 Open Access
Notes Approved Most recent IF: 3.411; 2000 IF: 3.906
Call Number UA @ lucian @ c:irua:103448 Serial 712
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Author Van Tendeloo, G.; Garlea, O.; Darie, C.; Bougerol-Chaillout, C.; Bordet, P.
Title The fine structure of YCuO2+x delafossite determined by synchrotron powder diffraction and electron microscopy Type A1 Journal article
Year 2001 Publication Journal of solid state chemistry Abbreviated Journal J Solid State Chem
Volume 156 Issue 2 Pages 428-436
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract YCuO2 delafossite crystallizes into two stacking variants; hexagonal 2H or rhombohedral 3R, depending on the preparation conditions. The structure of the fully oxygenated material YCuO2.50 has been determined as orthorhombic (a(O) = 6.1961 Angstrom; b(O) = 11.2158 Angstrom; c(O) = 7.1505 Angstrom; space group Pnma). The structure is based on the hexagonal 2H structure (a(O) = a(H)root3; b(O) = c(H); c(O) = 2a(H)). Upon incomplete oxidation, a different YCuOZ phase with ideal composition YCuO2.33 and lattice parameters a(H root)3, a(H)root3, c(H) is also formed. Diffraction patterns are often very complex because of the presence of planar defects and intergrowth of both phases. Under electron beam irradiation, oxygen is released from the structure and one phase gradually transforms into the other. (C) 2001 Academic Press.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000167252000025 Publication Date 2002-09-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-4596; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.299 Times cited 33 Open Access
Notes Approved Most recent IF: 2.299; 2001 IF: 1.614
Call Number UA @ lucian @ c:irua:103425 Serial 3581
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Author Nistor, L.; Teodorescu, V.; Ghica, C.; van Landuyt, J.; Dinca, G.; Georgeoni, P.
Title The influence of the h-BN morphology and structure on the c-BN growth Type A1 Journal article
Year 2001 Publication Diamond and related materials T2 – 11th European Conference on Diamond, Diamond-like Materials, Carbon, Nanotubes, Nitrides and Silicon Carbide (Diamond 2000), SEP 03-08, 2000, OPORTO, PORTUGAL Abbreviated Journal Diam Relat Mater
Volume 10 Issue 3-7 Pages 1352-1356
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The morphology and structure of hexagonal graphitic BN (h-BN) powders with graphitization indices GI <5, used as precursors for the synthesis of cubic BN (c-BN) crystals, has been investigated by transmission electron microscopy in diffraction contrast and high resolution. We show that besides the GI, which is a general parameter for controlling the structural quality of h-EN ponders, some other microstructural features strongly influence the synthesis of c-BN. In our opinion, the high reactivity of some h-BN powders results from the presence of some nucleation centers for c-BN, observed at the edges of the h-BN particles. They are formed by a rearrangement of the graphitic (0002) planes by bending back, joining in pairs and forming locally nanoarches (half nanotubes). In these particular places, the nature of bonding locally turns towards sp(3), as in the case of c-BN, (C) 2001 Elsevier Science B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000168730600206 Publication Date 2002-10-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0925-9635; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.561 Times cited 17 Open Access
Notes Approved Most recent IF: 2.561; 2001 IF: 1.902
Call Number UA @ lucian @ c:irua:103421 Serial 3586
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Author Koster, G.; Verbist, K.; Rijnders, G.; Rogalla, H.; Van Tendeloo, G.; Blank, D.H.A.
Title Structure and properties of (Sr,Ca)CuO2-BaCuO2 superlattices grown by pulsed laser interval deposition Type A1 Journal article
Year 2001 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 353 Issue 3-4 Pages 167-183
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We report on the preparation of CuBa(2)(Sr(x)Ca(1-x))(n)Cu(n-1)O(y) compounds by fabrication of (Ba,Sr,Ca)CuO(2) superlattices with pulsed laser deposition (PLD). A technique called interval deposition is used to suppress multi-level or island growth resulting in high-quality superlattice structures. Both, the applicability of PLD to atomic engineering as well as the fabrication of artificial superconductors is demonstrated. The (Sr,Ca)CuO(2)-BaCuO(2) superlattices are characterized by X-ray diffraction, high-resolution electron microscopy (HREM) and selected area electron diffraction. The superlattice period has been deduced from electron diffraction patterns and XRD measurements. For Sr containing films, the best growth behavior is observed and films with the highest degree of crystallinity are obtained, whereas superconductivity is only found in less crystalline, Ca containing films. Under some deposition conditions and depending on the amount of Ba containing layers in the superlattice, it was observed that the BaCuO(2) material is converted to Ba(2)CuO(4-delta). Image simulations to interpret the HREM contrast are performed. (C) 2001 Elsevier Science B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000168861100003 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4534; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.404 Times cited 8 Open Access
Notes Approved Most recent IF: 1.404; 2001 IF: 0.806
Call Number UA @ lucian @ c:irua:103417 Serial 3293
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Author Peeters, F.M.; Riva, C.; Varga, K.
Title Trions in quantum wells Type A1 Journal article
Year 2001 Publication Physica: B : condensed matter Abbreviated Journal Physica B
Volume 300 Issue 1-4 Pages 139-155
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract An overview is given of our investigation of the energy levels and of the correlation functions of the negatively and positively charged excitons (also called trions) in quantum wells in the presence of a perpendicular magnetic field, A detailed comparison is made with available experimental data in III-V and II-VI semiconductor quantum wells. (C) 2001 Elsevier Science B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000170850000011 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4526; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.386 Times cited 31 Open Access
Notes Approved Most recent IF: 1.386; 2001 IF: 0.663
Call Number UA @ lucian @ c:irua:103410 Serial 3734
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Author Mishra, R.S.K.; Pandey, D.; Lemmens, H.; Van Tendeloo, G.
Title Evidence for another low-temperature phase transition in tetragonal Pb(ZrxTi1-x)O3 (x=0.515,0.520) Type A1 Journal article
Year 2001 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 64 Issue 5 Pages 054104
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Results of dielectric and resonance frequency (f(r)) measurements below room temperature are presented for Pb(ZrxTi1-x)O-3, x = 0.515 and 0.520. It is shown that the temperature coefficient of f(r) changes sign from negative to positive around 210 and 265 K for x = 0.520 and 200 and 260 K for x = 0.515. Anomalies in the real part of the dielectric constant (epsilon') are observed around the same temperatures at which the temperature coefficient of f(r) changes sign because of the electrostrictive coupling between the elastic and dielectric responses. Low-temperature powder x-ray-diffraction (XRD) data, however, reveal only one transition from the tetragonal to monoclinic phase similar to that reported by Noheda et al. [Phys. Rev. B, 61, 8687 (2000)]. Electron-diffraction data, on the other hand, reveal yet another structural transition at lower temperatures corresponding to the second anomaly in the epsilon' vs T and f(r) vs T curves. This second transition is shown to be a cell-doubling transition not observed by Noheda et al. in their XRD studies. The observation of superlattice reflections raises doubts about the correctness of the Cm space group proposed by Noheda et al. for the monoclinic phase of Pb(ZrxTi(1-x))O-3 below the second transition temperature.
Address
Corporate Author Thesis
Publisher Place of Publication Lancaster, Pa Editor
Language Wos 000170267000028 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited Open Access
Notes Approved Most recent IF: 3.836; 2001 IF: NA
Call Number UA @ lucian @ c:irua:103407 Serial 1093
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Author Stuer, C.; van Landuyt, J.; Bender, H.; de Wolf, I.; Rooyackers, R.; Badenes, G.
Title Investigation by convergent beam electron diffraction of the stress around shallow trench isolation structures Type A1 Journal article
Year 2001 Publication Journal of the electrochemical society Abbreviated Journal J Electrochem Soc
Volume 148 Issue 11 Pages G597-G601
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Convergent beam electron diffraction (CBED) is used in this study to investigate the stress distribution around shallow trench isolation (STI) structures. Attention is given to the influence of the different processing parameters and the width and spacing of the structures. The use of a wet or a dry pregate oxidation is found to have a strong influence on the stress behavior. Isolated lines show more stress, leading to the formation of defects in the silicon substrate if a wet pregate oxidation is used. The CBED analyses are compared with micro-Raman and bright-field transmission electron microscopy measurements. (C) 2001 The Electrochemical Society.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000171653100038 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0013-4651; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.259 Times cited 13 Open Access
Notes Approved Most recent IF: 3.259; 2001 IF: 2.033
Call Number UA @ lucian @ c:irua:103394 Serial 1725
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Author de Gryse, O.; Clauws, P.; Lebedev, O.; van Landuyt, J.; Vanhellemont, J.; Claeys, C.; Simoen, E.
Title Chemical and structural characterization of oxygen precipitates in silicon by infrared spectroscopy and TEM Type A1 Journal article
Year 2001 Publication Physica: B : condensed matter T2 – 21st International Conference on Defects in Semiconductors, JUL 16-20, 2001, GIESSEN, GERMANY Abbreviated Journal Physica B
Volume 308 Issue Pages 294-297
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Infrared absorption spectra of polyhedral and platelet oxygen precipitates are analyzed using a modified Day-Thorpe approach (J. Phys.: Condens. Matter 11 (1999) 2551). The aspect ratio has been determined by TEM measurements. The reduced spectral function and the stoichiometry are extracted from the absorption spectra and the concentration of precipitated interstitial oxygen. One set of spectra reveal a Frohlich frequency around 1100 cm(-1) and another around 1110-1120 cm(-1). It is shown that the shift in the Frohlich frequency is not due to a different stoichiometry, but due to the detailed structure in the reduced spectral function. The oxygen precipitates consist of SiO. with gammaapproximate to1.1-1.2+/-0.1. (C) 2001 Elsevier Science B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Elsevier science bv Place of Publication Amsterdam Editor
Language Wos 000173660100073 Publication Date 2002-10-15
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4526; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.386 Times cited 3 Open Access
Notes Approved Most recent IF: 1.386; 2001 IF: 0.663
Call Number UA @ lucian @ c:irua:103389 Serial 345
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Author Peeters, F.M.; Riva, C.; Varga, K.
Title Trions in quantum wells Type A1 Journal article
Year 2002 Publication Few-body systems T2 – International Workshop on Dynamics and Structure of Critically Stable, Quantum Few-Body Systems, OCT 08-12, 2001, LES HOUCHES, FRANCE Abbreviated Journal Few-Body Syst
Volume 31 Issue 2-4 Pages 97-100
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The ground-state energy of three-particle systems consisting of electrons and holes as found in semiconducting quantum wells is studied. The degree of confinement is determined by the quantum-well width and we can vary the dimensionality of the system from two to three dimensions. The energy levels of the system can further be altered by the application of an external magnetic field which is directed perpendicular to the well.
Address
Corporate Author Thesis
Publisher Place of Publication Wien Editor
Language Wos 000176115900005 Publication Date 2003-03-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0177-7963;1432-5411; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 0.877 Times cited 2 Open Access
Notes Approved Most recent IF: 0.877; 2002 IF: 1.773
Call Number UA @ lucian @ c:irua:103378 Serial 3733
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Author Yampolskii, S.V.; Baelus, B.J.; Peeters, F.M.; Kolacek, J.
Title Electric charges in superconducting mesoscopic samples Type A1 Journal article
Year 2002 Publication Czechoslovak journal of physics T2 – 11th Czech and Slovak Conference on Magnetism (CSMAG 01), AUG 20-23, 2001, KOSICE, SLOVAKIA Abbreviated Journal Czech J Phys
Volume 52 Issue 2 Pages 303-306
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The distribution of the electric charge density in mesoscopic superconducting disks and cylinders is studied within the phenomenological Ginzburg-Landau approach. We found that, even in the Meissner state the mesoscopic sample exhibits a non-uniform charge distribution such that a region near the sample edge becomes negatively charged. When vortices are inside the sample there is a superposition of the negative charge located at the vortex core and this Meissner charge, and, as a result, the charge at the sample edge changes sign as a function of the applied magnetic field.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000174955600046 Publication Date 2002-12-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0011-4626; ISBN Additional Links (down) UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:103374 Serial 880
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Author Gryse, O.D.; Clauws, P.; van Landuyt, J.; Lebedev, O.; Claeys, C.; Simoen, E.; Vanhellemont, J.
Title Oxide phase determination in silicon using infrared spectroscopy and transmission electron microscopy techniques Type A1 Journal article
Year 2002 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 91 Issue 4 Pages 2493-2498
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Infrared absorption spectra of polyhedral and platelet oxygen precipitates in silicon are analyzed using a modified Day-Thorpe approach [J. Phys.: Condens. Matter 11, 2551 (1999)]. The aspect ratio of the precipitates is determined by transmission electron microscopy analysis. The reduced spectral function and the stoichiometry of the precipitate are extracted from the absorption spectra and the amount of precipitated interstitial oxygen. The experimental absorption spectra can be divided in a set with a Frohlich frequency of around 1100 cm(-1) and in a set with a Frohlich frequency between 1110 and 1120 cm(-1). It is shown that the shift in the Frohlich frequency is not due to a differing stoichiometry, but to the detailed structure of the reduced spectral function. Inverse modeling of the spectra suggests that the oxide precipitates consist of substoichiometric SiOgamma with gamma=1.17+/-0.14. (C) 2002 American Institute of Physics.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000173553800114 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 27 Open Access
Notes Approved Most recent IF: 2.068; 2002 IF: 2.281
Call Number UA @ lucian @ c:irua:103372 Serial 2542
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Author Tadić, M.; Peeters, F.M.; Janssens, K.L.
Title Effect of isotropic versus anisotropic elasticity on the electronic structure of cylindrical InP/In0.49Ga0.51P self-assembled quantum dots Type A1 Journal article
Year 2002 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 65 Issue 16 Pages 165333-13
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The electronic structure of disk-shaped InP/InGaP self-assembled quantum dots is calculated within the effective-mass theory. The strain-dependent 6x6 multiband Hamiltonian for the valence band is simplified into an axially symmetric form. Both the continuum mechanical model, discretized by finite elements, and the isotropic model are used to calculate the strain distribution and their results are critically compared. The dependence of the electron and the hole energy levels on the dimensions of the quantum dot is investigated. We found that both the electron and hole energies are underestimated if the strain distribution is calculated by the isotropic elasticity theory. The agreement between the electron energies for the two approaches is better for thinner quantum dots. The heavy holes are confined inside the quantum dot, while the light holes are located outside the disk, but confined by the strain field near the edge of the disk periphery. We found that the (h) over bar /2 hole ground state crosses the 3 (h) over bar /2 ground state when the height of the quantum dot increases and becomes the ground state for sufficiently thick quantum disks. The higher hole levels exhibit both crossings between the states of the different parity and anticrossings between the states of the same parity.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000175325000097 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 72 Open Access
Notes Approved Most recent IF: 3.836; 2002 IF: NA
Call Number UA @ lucian @ c:irua:103361 Serial 819
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Author Verberck, B.; Michel, K.H.; Nikolaev, A.V.
Title Crystal structures of polymerized fullerides AC60, A=K, Rb, Cs, and alkali-mediated interactions Type A1 Journal article
Year 2002 Publication The journal of chemical physics Abbreviated Journal J Chem Phys
Volume 116 Issue 23 Pages 10462-10474
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Starting from a model of rigid interacting C-60 polymer chains on an orthorhombic lattice, we study the mutual orientation of the chains and the stability of the crystalline structures Pmnn and I2/m. We take into account (i) van der Waals interactions and electric quadrupole interactions between C-60 monomers on different chains as well as (ii) interactions of the monomers with the surrounding alkali atoms. The direct interactions (i) always lead to an antiferrorotational structure Pmnn with alternate orientation of the C-60 chains in planes (001). The interactions (ii) with the alkalis consist of two parts: translation-rotation (TR) coupling where the orientations of the chains interact with displacements of the alkalis, and quadrupolar electronic polarizability (ep) coupling, where the electric quadrupoles on the C-60 monomers interact with induced quadrupoles due to excited electronic d-states of the alkalis. Both interactions (ii) lead to an effective orientation-orientation interaction between the C-60 chains and always favor the ferrorotational structure I2/m, where C-60 chains have a same orientation. The structures Pmnn for KC60 and I2/m for Rb- and CsC60 are the result of a competition between the direct interaction (i) and the alkali-mediated interactions (ii). In Rb- and CsC60 the latter are found to be dominant, the preponderant role being played by the quadrupolar electronic polarizability of the alkali ions. (C) 2002 American Institute of Physics.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000175905800044 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9606; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.965 Times cited 12 Open Access
Notes Approved Most recent IF: 2.965; 2002 IF: 2.998
Call Number UA @ lucian @ c:irua:103350 Serial 578
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Author Novoselov, K.S.; Geim, A.K.; Dubonos, S.V.; Cornelissens, Y.G.; Peeters, F.M.; Maan, J.C.
Title Scattering of ballistic electrons at a mesoscopic spot of strong magnetic field Type A1 Journal article
Year 2002 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 65 Issue 23 Pages 233312-233314
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We report quenching of the Hall effect with increasing magnetic field confined in a micron-sized spot. Such fields were created by placing tall ferromagnetic pillars on top of a two-dimensional electron gas, which allowed us to achieve the field strength up to 0.4 T under the pillars in the absence of external field. The quenching is accompanied by an anomalous increase in resistance and occurs when the cyclotron diameter matches the size of the magnetic spot. The results are explained by a rapid increase in the number of electrons that are scattered or quasilocalized by the magnetic region.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000176767900029 Publication Date 2002-07-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0163-1829;1095-3795; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 38 Open Access
Notes Approved Most recent IF: 3.836; 2002 IF: NA
Call Number UA @ lucian @ c:irua:103349 Serial 2949
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Author Lei, C.H.; Van Tendeloo, G.; Siegert, M.; Schubert, J.
Title Microstructural investigation of BaTiO3 thin films deposited on (001) MgO Type A1 Journal article
Year 2002 Publication Journal of materials research Abbreviated Journal J Mater Res
Volume 17 Issue 8 Pages 1923-1931
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The microstructure of BaTiO3 thin films, epitaxially deposited on (001) MgO by pulsed laser ablation, has been investigated by transmission electron microscopy. The films are always c-axis-orientated, but dislocations, {111} stacking faults, and antiphase boundaries are frequently observed. Conventional TEM and high-resolution microscopy allow one to deduce the Burgers vectors of dislocations as b(1) = <100> or b(2) = <110>, both being perfect dislocations. Most extrinsic stacking faults are ending at 1/3<112> or 1/3<111> partial dislocations; the displacement vector of the antiphase boundaries is 1/2<101>. Studying the interfacial structure by means of zone images taken along [100] and [110] shows that the misfit is mainly released by dislocations with Burgers vectors of 1/2<110> and 1/2<101>.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000177208800010 Publication Date 2008-03-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0884-2914;2044-5326; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.673 Times cited 8 Open Access
Notes Approved Most recent IF: 1.673; 2002 IF: 1.530
Call Number UA @ lucian @ c:irua:103343 Serial 2044
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Author Antipov, E.V.; Khasanova, N.R.; Pshirkov, J.S.; Putilin, S.N.; Bougerol, C.; Lebedev, O.I.; Van Tendeloo, G.; Baranov, A.N.; Park, Y.W.
Title The superconducting bismuth-based mixed oxides Type A1 Journal article
Year 2002 Publication Current applied physics T2 – QTSM and QFS 02 Symposium, MAY 08-10, 2002, SEOUL, SOUTH KOREA Abbreviated Journal Curr Appl Phys
Volume 2 Issue 5 Pages 425-430
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The present paper describes the synthesis, characterization of mixed-valence bismuthates with three- or two-dimensional perovskite-like structures and structural criteria that influence superconductivity in these compounds. Single-phase samples of Sr1-xKxBiO3 were prepared for the broad range of K-content: 0.25 less than or equal to x less than or equal to 0.65. For these bismuthates the symmetry of the structure changes from monoclinic to orthorhombic and finally to tetragonal upon increasing the K-content thus resulting in the decrease of the Bi-O distances and reduction of the network distortions. Superconductivity with maximum T-c = 12 K exists in the narrow range (x approximate to 0.5-0.6) within the stability field of the tetragonal phase (0.33 less than or equal to x less than or equal to 0.65), when the three-dimensional octahedral framework has close to the ideal perovskite structure arrangement. The layered type (Ba,K)(3)Bi2O7 and (Ba,K)(2)BiO4 bismuthates belonging to the A(n+1)B(n)O(3n+1) homologous series were investigated. Buckling of the (BiO2) layers in the structure of the n = 2 member occurs due to the ordering of alkaline- and alkaline-earth cations between two independent positions. The formation of the one-layer bismuthate was revealed by Electron Microscopy and XRPD studies. Both types of compounds are considered to be possible candidates for new superconducting materials among bismuthates. (C) 2002 Published by Elsevier Science B.V.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000179330900015 Publication Date 2002-11-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1567-1739; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.971 Times cited 2 Open Access
Notes Approved Most recent IF: 1.971; 2002 IF: NA
Call Number UA @ lucian @ c:irua:103336 Serial 3598
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Author Nistor, L.C.; Nistor, S.V.; Dinca, G.; Georgeoni, P.; van Landuyt, J.; Manfredotti, C.; Vittone, E.
Title Microstructure and spectroscopy studies on cubic boron nitride synthesized under high-pressure conditions Type A1 Journal article
Year 2002 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat
Volume 14 Issue 44 Pages 10983-10988
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract High-resolution electron microscopy (HREM) studies of the microstructure and specific defects in hexagonal boron nitride (h-BN) precursors and cubic boron nitride (c-BN) crystals made under high-pressure high-temperature conditions revealed the presence of half-nanotubes at the edges of the h-BN particles. Their sp(3) bonding tendency could strongly influence the nucleation rates of c-BN. The atomic resolution at extended dislocations was insufficient to allow us to determine the stacking fault energy in the c-BN crystals. Its mean value of 191 +/- 15 mJ m(-2) is of the same order of magnitude as that of diamond. High-frequency (94 GHz) electron paramagnetic resonance studies on c-BN single crystals have produced new data on the D1 centres associated with the boron species. Ion-beam-induced luminescence measurements have indicated that c-BN is a very interesting luminescent material, which is characterized by four luminescence bands and exhibits a better resistance to ionizing radiation than CVD diamond.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000179541700114 Publication Date 2002-10-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 7 Open Access
Notes Approved Most recent IF: 2.649; 2002 IF: 1.775
Call Number UA @ lucian @ c:irua:103328 Serial 2061
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Author Tadić, M.; Peeters, F.M.; Janssens, K.L.; Korkusinski, M.; Hawrylak, P.
Title Strain and band edges in single and coupled cylindrical InAs/GaAs and InP/InGaP self-assembled quantum dots Type A1 Journal article
Year 2002 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 92 Issue 10 Pages 5819-5829
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract A comparative study is made of the strain distribution in cylindrical InAs/GaAs and InP/InGaP self-assembled quantum dots as obtained from isotropic elasticity theory, the anisotropic continuum mechanical model, and from atomistic calculations. For the isotropic case, the recently proposed approach [J. H. Davies, J. Appl. Phys. 84, 1358 (1998)] is used, while the finite-element method, the valence force field method, and Stillinger-Weber potentials are employed to calculate the strain in anisotropic structures. We found that all four methods result in strain distributions of similar shapes, but with notable quantitative differences inside the dot and near the disk-matrix boundary. The variations of the diagonal strains with the height of the quantum dot, with fixed radius, as calculated from all models, are almost linear. Furthermore, the energies of the band edges in the two types of quantum dots are extracted from the multiband effective-mass theory by inserting the strain distributions as obtained by the four models. We demonstrated that all strain models produce effective potentials for the heavy and light holes which agree very well inside the dot. A negligible anisotropy of all normal strains in the (x,y) plane is found, which, providing the axial symmetry of the kinetic part of the multiband effective-mass Hamiltonian, justifies the use of the axial approximation. Strain propagation along the vertical direction is also considered with the aim to study the influence of strain on the electron coupling in stacks of quantum dots. We found that the interaction between the strain fields of the individual quantum dots makes the effective quantum wells for the electrons in the conduction band shallower, thereby counteracting the quantum mechanical coupling. (C) 2002 American Institute of Physics.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000178987200036 Publication Date 2002-11-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 73 Open Access
Notes Approved Most recent IF: 2.068; 2002 IF: 2.281
Call Number UA @ lucian @ c:irua:103327 Serial 3164
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Author Simoen, E.; Loo, R.; Claeys, C.; de Gryse, O.; Clauws, P.; van Landuyt, J.; Lebedev, O.
Title Optical spectroscopy of oxygen precipitates in heavily doped p-type silicon Type A1 Journal article
Year 2002 Publication Journal of physics : condensed matter T2 – Conference on Extended Defects in Semiconductors (EDS 2002), JUN 01-06, 2002, BOLOGNA, ITALY Abbreviated Journal J Phys-Condens Mat
Volume 14 Issue 48 Pages 13185-13193
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Results are presented on the photoluminescence (PL) characterization of heavily doped p(+) Czochralski silicon, which has been subjected to a two-step, oxygen precipitation heat treatment. It will be shown that the presence of oxygen precipitates gives rise to the D1, D2 and D5 lines, where the energy of the D1 line shifts to lower values for a stronger degree of precipitation. The occurrence of these PL features is also a function of the boron concentration in the p(+) material. The PL results are compared with Fourier transform infrared absorption data and with transmission electron microscope, results. From this, it is concluded that PL has a good potential for use in the assessment of oxygen precipitation in heavily doped silicon.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000180091100068 Publication Date 2002-11-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0953-8984; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 2.649 Times cited 3 Open Access
Notes Approved Most recent IF: 2.649; 2002 IF: 1.775
Call Number UA @ lucian @ c:irua:103326 Serial 2477
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Author Bencs, L.; Szakács, O.; Szoboszlai, N.; Ajtony, Z.; Bozsai, G.
Title Characteristics of atomic absorption calibration curves with the transversely heated graphite furnace Type A1 Journal article
Year 2003 Publication Journal of analytical atomic spectrometry Abbreviated Journal
Volume 18 Issue 2 Pages 105-110
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Calibration curves with two quasi-linear sections ("double sloping'') were observed for the medium volatile elements, Cr and Cu, with the use of a SIMAA 6000 graphite furnace atomic absorption spectrometer under interrupted internal gas flow conditions. If a standard transversally heated graphite atomizer (THGA) tube was shortened by 0.5 mm at both of its ends, (i.e. the gaps were enlarged between graphite furnace housing and tube ends), a stronger declination of the calibration curves resulted. Elements with fairly high diffusion coefficients (>5.8 cm(2) s(-1)) and with short appearance time of their transients (<0.6 s), such as Cr and Cu, have shown the most characteristic sensitivity drop towards higher concentrations. This anomalous feature could be eliminated in three different ways; (1) by applying end-capped THGA tubes, (2) using mini-flow (50 cm(3) min(-1)) conditions during the atomization stage, and (3) by adding Pd-Mg chemical modifier. For the low volatile Mo and V, the calibration curves had no irregular shape. For Ag, Co, Cr, Cu, Mn and Ni, the mini-flow settings improved the linearity of the calibration curves and extended the upper limit of the linear calibration range by a factor of 1.5-2.0. The irregular characteristic of the analytical curves was interpreted as an increased vapour loss at higher analyte concentrations through the opened ends of the standard THGA tubes. This vapour loss was associated with the significantly diverse expulsion velocities of atoms, caused by the difference in temperature and concentration gradients, when evaporating amounts of analytes with more than one order of magnitude difference.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000180666600003 Publication Date 2003-01-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0267-9477 ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:103320 Serial 7606
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Author Krstajic, P.M.; Ivanov, V.A.; Peeters, F.M.; Fleurov, V.; Kikoin, K.
Title On the nature of ferromagnetism in diluted magnetic semiconductors : GaAs:Mn Type A1 Journal article
Year 2003 Publication Europhysics letters Abbreviated Journal Epl-Europhys Lett
Volume 61 Issue 2 Pages 235-241
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract An energy level diagram is constructed on the basis of a microscopic Hamiltonian proposed for a description of interacting manganese impurities in diluted magnetic semiconductors (DMS). It is shown that ferromagnetism in p-type III-V DMS is governed by the strong hybridization of Mn2+-electrons with the mobile holes and localized states near the top of the valence band. The Curie temperature estimated from the proposed kinematic exchange agrees with the experiments on GaAs:Mn. The model is also applicable to the GaP:Mn system.
Address
Corporate Author Thesis
Publisher Place of Publication Paris Editor
Language Wos 000180283200015 Publication Date 2003-12-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0295-5075;1286-4854; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor 1.957 Times cited 38 Open Access
Notes Approved Most recent IF: 1.957; 2003 IF: 2.075
Call Number UA @ lucian @ c:irua:103318 Serial 2443
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Author Krstajic, P.M.; Ivanov, V.A.; Peeters, F.M.; Fleurov, V.; Kikoin, K.
Title Ferromagnetism in Mn-doped GaAs : the kinematic exchange Type A1 Journal article
Year 2003 Publication Journal of superconductivity T2 – PASPS Conference 2002, JUL, 2002, WURZBURG, GERMANY Abbreviated Journal J Supercond
Volume 16 Issue 1 Pages 111-113
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We developed a microscopic model in order to describe the onset of ferromagnetism (FM) in GaAs:Mn. The proposed kinematic mechanism bears resemblances with the Zener exchange. The calculated Curie temperature for GaAs: Mn is in good agreement with available experimental data of the Curie temperature as a function of the manganese concentration.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000182060400027 Publication Date 2003-06-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0896-1107; ISBN Additional Links (down) UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 2 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:103314 Serial 1183
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