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Author Fang, P.a.; Gu, H.; Wang, P.l.; Van Landuyt, J.; Vleugels, J.; Van der Biest, O.;
  Title Effect of powder coating on stabilizer distribution in CeO2-stabilized ZrO2 ceramics Type A1 Journal article
  Year 2005 Publication Journal of the American Ceramic Society Abbreviated Journal J Am Ceram Soc
  Volume 88 Issue 7 Pages 1929-1934
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract The phase and microstructure relationship of 12 mol% CeO2-stabilized ZrO2 ceramics prepared from coated powder was investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersed Xray spectroscopy (EDS). As compared with the sample prepared with co-precipitated method, which exhibited a similar grain size distribution, the EDS analysis revealed that the powder coating induced a wide distribution of CeO2 solubility, which decreases monotonically with the increase of grain size. This variation of stabilizer content from grain to grain rendered many large grains in the monoclinic phase. Stronger cerium segregation to grain boundaries was observed between large grains, which often form thin amorphous films there. The inhomogeneous; CeO2 distribution keeps more tetragonal ZrO2 grains close to the phase boundary to facilitate the transforming toughness. Addition of an Al2O3 precursor in coated powders effectively raises the overall CeO2 stabilizer content in the grains and preserves more transformable tetragonal phase in the microstructure, which further enhanced the fracture toughness. The dependence of CeO2 solubility on grain size may be explained in a simple coating-controlled diffusion and growth process that deserves further investigation.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Columbus, Ohio Editor
  Language Wos 000230128100040 Publication Date 2005-06-23
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0002-7820;1551-2916; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 2.841 Times cited 11 Open Access
  Notes Approved Most recent IF: 2.841; 2005 IF: 1.586
  Call Number UA @ lucian @ c:irua:103156 Serial 830
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Author Yang, W.; Chang, K.; Peeters, F.M.
  Title Spin-polarized transport of two-dimensional electron gas embedded in a diluted magnetic semiconductor Type A1 Journal article
  Year 2005 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
  Volume 86 Issue 19 Pages 192107-3
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  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.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000229397900042 Publication Date 2005-05-03
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0003-6951; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 3.411 Times cited 10 Open Access
  Notes Approved Most recent IF: 3.411; 2005 IF: 4.127
  Call Number UA @ lucian @ c:irua:103163 Serial 3097
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Author Tadić, M.; Mlinar, V.; Peeters, F.M.
  Title Multiband k\cdot p calculation of exciton diamagnetic shift in InP/InGaP self-assembled quantum dots Type A1 Journal article
  Year 2005 Publication Physica. E: Low-dimensional systems and nanostructures T2 – 3rd International Conference on Quantum Dots (QD 2004), MAY 10-13, 2004, Max Bell Bldg Banff Ctr, Banff, Canada Abbreviated Journal Physica E
  Volume 26 Issue 1-4 Pages 212-216
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
  Abstract Exciton states in self-assembled InP/In0.49Ga0.51P quantum dots subject to magnetic fields up to 50T are calculated. Strain and band mixing are explicitly taken into account in the single-particle models of the electronic structure, while an exact diagonalization approach is adopted to compute the exciton states. Reasonably good agreement with magneto-photoluminescence measurements on InP self-assembled quantum dots is found. As a result of the polarization and angular momentum sensitive selection rules, the exciton ground state is dark. For in-plane polarized light, the magnetic field barely affects the exciton spatial localization, and consequently the exciton oscillator strength for recombination increases only slightly with increasing field. For z polarized light, a sharp increase of the oscillator strength beyond 30 T is found which is attributed to the enhanced s character of the relevant portion of the exciton wave function. (C) 2004 Elsevier B.V. All rights reserved.
  Address
  Corporate Author Thesis
  Publisher North-Holland Place of Publication Amsterdam Editor
  Language Wos 000227249000045 Publication Date 2004-12-16
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1386-9477; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 2.221 Times cited 4 Open Access
  Notes Approved Most recent IF: 2.221; 2005 IF: 0.946
  Call Number UA @ lucian @ c:irua:103180 Serial 2215
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Author Szafran, B.; Peeters, F.M.; Bednarek, S.; Adamowski, J.
  Title Exact broken-symmetry states and Hartree-Fock solutions for quantum dots at high magnetic fields Type A1 Journal article
  Year 2005 Publication Physica. E: Low-dimensional systems and nanostructures T2 – 3rd International Conference on Quantum Dots (QD 2004), MAY 10-13, 2004, Max Bell Bldg Banff Ctr, Banff, Canada Abbreviated Journal Physica E
  Volume 26 Issue 1-4 Pages 252-256
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
  Abstract Wigner molecules formed at high magnetic fields in circular and elliptic quantum dots are studied by exact diagonalization (ED) and unrestricted Hartree-Fock (UHF) methods with multicenter basis of displaced lowest Landau level wave functions. The broken symmetry states with semi-classical charge density constructed from superpositions of the ED solutions are compared to the UHF results. UHF overlooks the dependence of the few-electron wave functions on the actual relative positions of electrons localized in different charge puddles and partially compensates for this neglect by an exaggerated separation of charge islands which are more strongly localized than in the exact broken-symmetry states. (C) 2004 Elsevier B.V. All rights reserved.
  Address
  Corporate Author Thesis
  Publisher North-Holland Place of Publication Amsterdam Editor
  Language Wos 000227249000053 Publication Date 2004-12-16
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1386-9477; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 2.221 Times cited 2 Open Access
  Notes Approved Most recent IF: 2.221; 2005 IF: 0.946
  Call Number UA @ lucian @ c:irua:103181 Serial 1105
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Author Shanenko, A.A.
  Title Imperfect fermi gas : kinetic and interaction energies Type A1 Journal article
  Year 2004 Publication Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A
  Volume 70 Issue 6 Pages 063618-13
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract A uniform ground-state three-dimensional Fermi gas with short-range repulsive pairwise interaction is under consideration. Its kinetic and interaction energies are calculated up to the second order of the expansion in the gas parameter. Similar to recent results for an interacting Bose gas, the quantities in question are found to depend on the pairwise interaction through two characteristic lengths: the former, a, is the s-wave scattering length, and the latter, b, is related to a by b=a-m(partial derivativea/partial derivativem), where m stands for the fermion mass. To control the results, we proceed in two independent ways. The first involves the Hellmann-Feynman theorem applied to derive the kinetic and interaction energies from the total-energy expansion in the gas parameter first found by Huang and Yang. The second way operates with in-medium pair wave functions and allows one to calculate the quantities of interest “from scratch.” The results of the present investigation, taken together with those of the recent consideration of a dilute Bose gas, make it possible to conclude that the pairwise interaction in a quantum gas has an essential and nontrivial effect on the kinetic energy, which is not the case for a classical many-particle system.
  Address
  Corporate Author Thesis
  Publisher American Physical Society Place of Publication New York, N.Y Editor
  Language Wos 000226418900116 Publication Date 2004-12-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1050-2947;1094-1622; ISBN Additional Links (up) UA library record; WoS full record
  Impact Factor 2.925 Times cited Open Access
  Notes Approved Most recent IF: 2.925; 2004 IF: 2.902
  Call Number UA @ lucian @ c:irua:103196 Serial 1562
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Author Wang, X.F.; Vasilopoulos, P.; Peeters, F.M.
  Title Influence of spin-orbit interaction on the magnetotransport of a periodically modulated two-dimensional electron gas Type A1 Journal article
  Year 2004 Publication International journal of modern physics: B: condensed matter physics, statistical physics, applied physics T2 – 16th International Conference on High Magnetic Fields in Semiconductor, Physics, AUG 02-06, 2004, Florida State Univ, NHMFL, Tallahassee, FL Abbreviated Journal Int J Mod Phys B
  Volume 18 Issue 27-29 Pages 3653-3656
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Transport properties of a two-dimensional electron gas (2DEG) are studied in the presence of a normal magnetic field B, of a weak one-dimensional (1D) periodic potential modulation V(x) = V(0)cos(Kx), and of the Rashba spin-orbit interaction (SOI) of strength a. For V(x) = 0 the SOI mixes the up and down spin states of neighboring Landau levels into two, unequally spaced energy branches. For V(x) not equal 0 these levels broaden into bands and their bandwidths oscillate with B. The n-th level bandwidth of each series vanishes at different values of B. Relative to the ID-modulated 2DEG without SOI and one flat-band condition, there are two flat-band conditions that depend on a and the transport coefficients can change considerably. For weak a the Weiss oscillations show beating patterns while for strong a the Shubnikov-de Haas ones axe split in two.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Singapore Editor
  Language Wos 000227140200040 Publication Date 2005-04-12
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0217-9792;1793-6578; ISBN Additional Links (up) UA library record; WoS full record
  Impact Factor 0.736 Times cited Open Access
  Notes Approved Most recent IF: 0.736; 2004 IF: 0.361
  Call Number UA @ lucian @ c:irua:103199 Serial 1633
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Author Szafran, B.; Peeters, F.M.
  Title Re-entrant pinning of Wigner molecules in a magnetic field due to a Coulomb impurity Type A1 Journal article
  Year 2004 Publication Europhysics letters Abbreviated Journal Epl-Europhys Lett
  Volume 66 Issue 5 Pages 701-707
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Pinning of magnetic-field-induced Wigner molecules (WMs) confined in parabolic two-dimensional quantum dots by a charged defect is studied by an exact diagonalization approach. We found a re-entrant pinning of the WMs as a function of the magnetic field, a magnetic-field-induced re-orientation of the WMs and a qualitatively different pinning behaviour in the presence of a positive and negative Coulomb impurity.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Paris Editor
  Language Wos 000223064900014 Publication Date 2004-05-27
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0295-5075;1286-4854; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 1.957 Times cited 11 Open Access
  Notes Approved Most recent IF: 1.957; 2004 IF: 2.120
  Call Number UA @ lucian @ c:irua:103226 Serial 2816
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Author Filinov, A.V.; Peeters, F.M.; Riva, C.; Lozovik, Y.E.; Bonitz, M.
  Title Exciton molecules in quantum wells : influence of the well width fluctuations Type A1 Journal article
  Year 2004 Publication Few-body systems T2 – 3rd International Workshop on Dynamics and Structure of Critically, Stable Quantum Few-Body Systems, SEP 01-05, 2003, Trento, ITALY Abbreviated Journal Few-Body Syst
  Volume 34 Issue 1-3 Pages 149-154
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The influence of the well width fluctuations on the dependence of the binding energy of excitonic complexes in quantum wells is studied by using the path-integral Monte-Carlo technique. The results are compared with available experimental data and a good agreement is found.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Wien Editor
  Language Wos 000222009500025 Publication Date 2004-05-18
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0177-7963;1432-5411; ISBN Additional Links (up) 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; 2004 IF: 1.948
  Call Number UA @ lucian @ c:irua:103232 Serial 1113
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Author Fleurov, V.; Kikoin, K.; Ivanov, V.A.; Krstajic, P.M.; Peeters, F.M.
  Title Mechanisms of double magnetic exchange in dilute magnetic semiconductors Type A1 Journal article
  Year 2004 Publication Journal of magnetism and magnetic materials T2 – International Conference on Magnetism (ICM 2003), JUL 27-AUG 01, 2003, Rome, ITALY Abbreviated Journal J Magn Magn Mater
  Volume 272 Issue Part 3 Pages 1967-1968
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract A microscopic Hamiltonian for interacting manganese impurities in dilute magnetic semiconductors (DMS) is derived. It is shown that in p-type III-V DMS, the indirect exchange between Mn impurities has similarities with the Zener mechanism in transition metal oxides. Here the mobile and localized holes near the top of the valence band play the role of unoccupied p-orbitals which induce ferromagnetism. T-C estimated from the proposed kinematic exchange agrees with experiments on (Ga,Mn)As. The model is also applicable to the p-doped (Ga,Mn)P system. The magnetic ordering in n-type (Ga,Mn)N is due to exchange between the electrons localized on the levels lying deep in the forbidden energy gap. This mechanism is even closer to the original Zener mechanism. (C) 2003 Elsevier B.V. All rights reserved.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Amsterdam Editor
  Language Wos 000222236800142 Publication Date 2004-01-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0304-8853; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 2.63 Times cited 12 Open Access
  Notes Approved Most recent IF: 2.63; 2004 IF: 1.031
  Call Number UA @ lucian @ c:irua:103233 Serial 1981
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Author Shanenko, A.A.; Ivanov, V.A.
  Title Effects of confining interaction in meso-superconductors Type A1 Journal article
  Year 2004 Publication Physics letters : A Abbreviated Journal Phys Lett A
  Volume 322 Issue 5-6 Pages 384-389
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract This Letter presents a generalized Ginzburg-Landau equation for the superconducting order parameter which includes the terms resulting from the confining interaction associated with the specimen boundary. While the original Ginzburg-Landau theory had been developed for a bulk superconductor, this generalization is meant for study of a meso-superconductor. (C) 2004 Elsevier B.V. All rights reserved.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Amsterdam Editor
  Language Wos 000220123600018 Publication Date 2004-02-05
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0375-9601; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 1.772 Times cited 1 Open Access
  Notes Approved Most recent IF: 1.772; 2004 IF: 1.454
  Call Number UA @ lucian @ c:irua:103244 Serial 859
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Author Szafran, B.; Bednarek, S.; Adamowski, J.; Tavernier, M.B.; Anisimovas, E.; Peeters, F.M.
  Title Accuracy of the Hartree-Fock method for Wigner molecules at high magnetic fields Type A1 Journal article
  Year 2004 Publication European physical journal : D : atomic, molecular and optical physics Abbreviated Journal Eur Phys J D
  Volume 28 Issue 3 Pages 373-380
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Few-electron systems confined in two-dimensional parabolic quantum dots at high magnetic fields are studied by the Hartree-Fock (HF) and exact diagoiialization methods. A generalized multicenter Gaussian basis is proposed in the HF method. A comparison of the HF and exact, results allows as to discuss the relevance of the symmetry of the charge density distribution for the accuracy of the HF method. It is shown that the energy estimates obtained with the broken-symmetry HF wave functions become exact in the infinite magnetic-field limit. In this limit the charge density of the broken-symmetry solution call be identified with the classical charge distribution.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Berlin Editor
  Language Wos 000220378400008 Publication Date 2004-03-19
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1434-6060;1434-6079; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 1.288 Times cited 14 Open Access
  Notes Approved Most recent IF: 1.288; 2004 IF: 1.692
  Call Number UA @ lucian @ c:irua:103246 Serial 43
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Author Kirschhock, C.E.A.; Liang, D.; Aerts, A.; Aerts, C.A.; Kremer, S.P.B.; Jacobs, P.A.; Van Tendeloo, G.; Martens, J.A.
  Title On the TEM and AFM evidence of zeosil nanoslabs present during the synthesis of silicalite-1 : reply Type L1 Letter to the editor
  Year 2004 Publication Angewandte Chemie: international edition in English Abbreviated Journal Angew Chem Int Edit
  Volume 43 Issue 35 Pages 4562-4564
  Keywords L1 Letter to the editor; Electron microscopy for materials research (EMAT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher Place of Publication Weinheim Editor
  Language Wos 000224008400003 Publication Date 2004-08-20
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1433-7851;1521-3773; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 11.994 Times cited Open Access
  Notes Fwo; Iap-Pai Approved Most recent IF: 11.994; 2004 IF: 9.161
  Call Number UA @ lucian @ c:irua:103253 Serial 2457
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Author Laffez, P.; Lebedev, O.I.; Ruello, P.; Desfeux, R.; Banerjee, G.; Capon, F.
  Title Evidence of strain induced structural change in hetero-epitaxial NdNiO3 thin films with metal-insulator transition Type A1 Journal article
  Year 2004 Publication European physical journal: applied physics Abbreviated Journal Eur Phys J-Appl Phys
  Volume 25 Issue 1 Pages 25-31
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Neodymium nickelate thin films have been prepared on NdGaO3 substrates by RF magnetron sputtering and post-annealing treatment under oxygen pressure. Transport properties are found to depend strongly on film thickness. Thick films show transport properties close to bulk ceramics, while very thin films exhibit a large transition from metal to insulator which occurs over a wide temperature range with high resistivity. Structure and surface morphology of the films have been investigated by Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM). Thin films (approximate to17 nm) grow heteroepitaxially, while thicker films (approximate to73 nm) show a granular structure. The thinnest sample suggests a symmetry change induced by the epitaxial strain of the substrate. This paper discusses the relationship between microstructure and transport properties.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Paris Editor
  Language Wos 000187286000003 Publication Date 2003-12-15
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1286-0042;1286-0050; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 0.684 Times cited 12 Open Access
  Notes Approved Most recent IF: 0.684; 2004 IF: 0.745
  Call Number UA @ lucian @ c:irua:103256 Serial 1096
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Author Papp, G.; Peeters, F.M.
  Title Comment on “Tunable spin-injection and magnetoconductance in a novel 2DEG-ferromagnet structure” [phys. stat. sol. (b) 235, No. 1, 157-161 (2003)] Type A1 Journal article
  Year 2004 Publication Physica status solidi: B: basic research Abbreviated Journal Phys Status Solidi B
  Volume 241 Issue 1 Pages 222-223
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract We point out that the predicted strong spin-injection effect by Jiang and Jalil [phys. stat. sol. (b) 235, 157 (2003)] for a double magnetic barrier structure is based on a wrong calculation of the transmission probability. We corrected the result and found no significant spin-injection.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Berlin Editor
  Language Wos 000188585200028 Publication Date 2003-12-29
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0370-1972;1521-3951; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 1.674 Times cited 11 Open Access
  Notes Approved Most recent IF: 1.674; 2004 IF: 0.982
  Call Number UA @ lucian @ c:irua:103257 Serial 413
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Author Verberck, B.; Nikolaev, A.V.; Michel, K.H.
  Title Theoretical model for the structural phase transition and the metal-insulator transition in polymerized KC60 Type A1 Journal article
  Year 2004 Publication Fullerenes, nanotubes, and carbon nanostructures T2 – 6th Biennial International Workshop on Fullerenes and Atomic Clusters, JUN 30-JUL 04, 2003, St Petersburg, RUSSIA Abbreviated Journal Fuller Nanotub Car N
  Volume 12 Issue 1-2 Pages 243-252
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
  Abstract The recently discovered structural phase transition in Polymerized KC60 at about 50K leads to a doubling of the unit cell volume and is accompanied by a metal-insulator transition. Here, we show that the ((a) over right arrow + (c) over right arrow, (b) over right arrow, (a) over right arrow – (c) over right arrow) superstructure results from orientational charge density waves along the polymer chains and correlated displacements of the K+ ions. The presented model can also account for the metal-insulator transition. The effect is specific for the space group Pmnn of KC60 and is absent in both Rb- and CsC60 (space group 12/m), in agreement with the present experimental knowledge of these compounds.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000220551600040 Publication Date 2004-03-15
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1536-383X;1536-4046; ISBN Additional Links (up) UA library record; WoS full record
  Impact Factor 1.35 Times cited Open Access
  Notes Approved Most recent IF: 1.35; 2004 IF: 1.117
  Call Number UA @ lucian @ c:irua:103259 Serial 3607
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Author Linssen, T.; Cassiers, K.; Cool, P.; Lebedev, O.; Whittaker, A.; Vansant, E.F.
  Title Physicochemical and structural characterization of mesoporous aluminosilicates synthesized from leached saponite with additional aluminum incorporation Type A1 Journal article
  Year 2003 Publication Chemistry of materials Abbreviated Journal Chem Mater
  Volume 15 Issue 25 Pages 4863-4873
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
  Abstract A thorough investigation was performed on the physical (mechanical, thermal, and hydrothermal stability) and chemical (ion exchange capacity and silanol number) characteristics of aluminosilicate FSMs, synthesized via a new successful short-time synthesis route using leached saponite and a low concentration of CTAB. Moreover, the influence of an additional Al incorporation, utilizing different aluminum sources, on the structure of the FSM derived from saponite is studied. A mesoporous aluminosilicate with a low Si/Al ratio of 12.8 is synthesized, and still has a very large surface area of 1130 m(2)/g and pore volume of 0.92 cm(3)/g. The aluminum-containing samples all have a high cation exchange capacity of around 1 mmol/9 while they still have a silanol number of about 0.9 OH/nm(2); both characteristics being interesting for high-yield postsynthesis modification reactions. Finally, a study is performed on the transformation of the aluminosilicates into their Bronsted acid form via the exchange with ammonium ions and a consecutive heat treatment.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Washington, D.C. Editor
  Language Wos 000187250800026 Publication Date 2003-12-09
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0897-4756;1520-5002; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 9.466 Times cited 11 Open Access
  Notes Approved Most recent IF: 9.466; 2003 IF: 4.374
  Call Number UA @ lucian @ c:irua:103265 Serial 2618
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Author Ball, J.M.; Schryvers, D.
  Title The analysis of macrotwins in NiAl martensite Type A1 Journal article
  Year 2003 Publication Journal de physique: 4 T2 – 10th International Conference on Martensitic Transformations, JUN 10-14, 2002, ESPOO, FINLAND Abbreviated Journal J Phys Iv
  Volume 112 Issue Part 1 Pages 159-162
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract We present a theoretical study of macrotwins arising in cubic to tetragonal martensitic transformations. The results help to explain some features of such macrotwins observed in Ni65Al35.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Les Ulis Editor
  Language Wos 000186503200024 Publication Date 2008-08-19
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1155-4339; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor Times cited 11 Open Access
  Notes Approved Most recent IF: NA
  Call Number UA @ lucian @ c:irua:103275 Serial 3569
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Author Lazoryak, B.I.; Baryshnikova, O.V.; Stefanovich, S.Y.; Malakho, A.P.; Morozov, V.A.; Belik, A.A.; Leonidov, I.A.; Leonidova, O.N.; Van Tendeloo, G.
  Title Ferroelectric and ionic-conductive properties of nonlinear-optical vanadate, Ca9Bi(VO4)7 Type A1 Journal article
  Year 2003 Publication Chemistry of materials Abbreviated Journal Chem Mater
  Volume 15 Issue 15 Pages 3003-3010
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Structural, chemical, and physical properties of whitlockite-type Ca9Bi(VO4)(7) were studied by X-ray powder diffraction (XRD), electron diffraction (ED), second-harmonic generation (SHG), thermogravimetry, differential scanning calorimetry, dielectric, and electrical-conductivity measurements. A new phase-transition of the ferroelectric type was found in Ca9Bi(VO4)(7) with a transition temperature, T-c of 1053 +/- 3 K. The polar phase, beta-Ca9Bi(VO4)(7), is stable below T-c down to at least 160 K. The centrosymmetric beta'-phase is stable above T-c up to 1273 +/- 5 K. Above 1273 K, it decomposes to give BiVO4 and whitlockite-type solid solutions of Ca9+1.5xBi1-x(VO4)(7). The beta<---->beta' phase transition is reversible and of second order. Electrical conductivity of beta'-Ca9Bi(VO4)(7) is rather high (sigma = 0.6 x 10(-3) S/cm at 1200 K) and obeys the Arrhenius law with an activation energy of 1.0 eV. Structure parameters of Ca9Bi(VO4)(7) are refined by the Rietveld method from XRD data measured at room temperature (space group R3c; Z = 6; a = 10.8992(1) Angstrom, c = 38.1192(4) Angstrom, and V = 3921.6(1) Angstrom(3); R-wp = 3.06% and R-p = 2.36%). Bi3+ ions together with Ca2+ ions are statistically distributed among the M1, M2, M3, and M5 sites. Ca9Bi(VO4)(7) has a SHG efficiency of about 140 times that of quartz. Through the powder SHG measurements, we estimated the nonlinear optical susceptibility, Digital, at about 6.1-7.2 pm/V. This value for Ca9Bi(VO4)(7) is comparable with that for known nonlinear optical materials such as LiNbO3 and LiTaO3.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Washington, D.C. Editor
  Language Wos 000184379900024 Publication Date 2003-07-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0897-4756;1520-5002; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 9.466 Times cited 51 Open Access
  Notes Iup V-1; Dwtc Approved Most recent IF: 9.466; 2003 IF: 4.374
  Call Number UA @ lucian @ c:irua:103284 Serial 1179
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Author Bals, S.; Van Tendeloo, G.; Rijnders, G.; Huijben, M.; Leca, V.; Blank, D.H.A.
  Title Transmission electron microscopy on interface engineered superconducting thin films Type A1 Journal article
  Year 2003 Publication IEEE transactions on applied superconductivity Abbreviated Journal Ieee T Appl Supercon
  Volume 13 Issue 2:3 Pages 2834-2837
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Transmission electron microscopy is used to evaluate different deposition techniques, which optimize the microstructure and physical properties of superconducting thin films. High-resolution electron microscopy proves that the use of an YBa2Cu2Ox buffer layer can avoid a variable interface configuration in YBa2Cu3O7-delta thin films grown on SrTiO3. The growth can also be controlled at an atomic level by, using sub-unit cell layer epitaxy, which results in films with high quality and few structural defects. Epitaxial strain in Sr0.85La0.15CuO2 infinite layer thin films influences the critical temperature of these films, as well as the microstructure. Compressive stress is released by a modulated or a twinned microstructure, which eliminates superconductivity. On the other hand, also tensile strain seems to lower the critical temperature of the infinite layer.
  Address
  Corporate Author Thesis
  Publisher Place of Publication New York, N.Y. Editor
  Language Wos 000184242400101 Publication Date 2003-07-16
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1051-8223; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor Times cited 13 Open Access
  Notes Iuap V-1; Fwo Approved Most recent IF: NA
  Call Number UA @ lucian @ c:irua:103292 Serial 3712
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Author Yu, M.Y.; Yu, W.; Chen, Z.Y.; Zhang, J.; Yin, Y.; Cao, L.H.; Lu, P.X.; Xu, Z.Z.
  Title Electron acceleration by an intense short-pulse laser in underdense plasma Type A1 Journal article
  Year 2003 Publication Physics of plasmas Abbreviated Journal Phys Plasmas
  Volume 10 Issue 6 Pages 2468-2474
  Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
  Abstract Electron acceleration from the interaction of an intense short-pulse laser with low density plasma is considered. The relation between direct electron acceleration within the laser pulse and that in the wake is investigated analytically. The magnitude and location of the ponderomotive-force-caused charge separation field with respect to that of the pulse determine the relative effectiveness of the two acceleration mechanisms. It is shown that there is an optimum condition for acceleration in the wake. Electron acceleration within the pulse dominates as the pulse becomes sufficiently short, and the latter directly drives and even traps the electrons. The latter can reach ultrahigh energies and can be extracted by impinging the pulse on a solid target. (C) 2003 American Institute of Physics.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Woodbury, N.Y. Editor
  Language Wos 000183316500031 Publication Date 2003-05-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1070-664X; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 2.115 Times cited 41 Open Access
  Notes Approved Most recent IF: 2.115; 2003 IF: 2.146
  Call Number UA @ lucian @ c:irua:103293 Serial 904
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Author Papp, G.; Peeters, F.M.
  Title Strong wave-vector filtering and nearly 100% spin polarization through resonant tunneling antisymmetrical magnetic structure (vol 81, pg 691, 2002) Type L1 Letter to the editor
  Year 2003 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
  Volume 82 Issue 20 Pages 3570-3570
  Keywords L1 Letter to the editor; Condensed Matter Theory (CMT)
  Abstract
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000182823300065 Publication Date 2003-05-15
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0003-6951; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 3.411 Times cited 21 Open Access
  Notes Approved Most recent IF: 3.411; 2003 IF: 4.049
  Call Number UA @ lucian @ c:irua:103295 Serial 3185
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Author Cassiers, K.; van der Voort, P.; Linssen, T.; Vansant, E.F.; Lebedev, O.; van Landuyt, J.
  Title A counterion-catalyzed (S0H+)(X-I+) pathway toward heat- and steam-stable mesostructured silica assembled from amines in acidic conditions Type A1 Journal article
  Year 2003 Publication The journal of physical chemistry : B : condensed matter, materials, surfaces, interfaces and biophysical Abbreviated Journal J Phys Chem B
  Volume 107 Issue 16 Pages 3690-3696
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
  Abstract An alternative pathway to assemble mesoporous molecular sieve silicas is developed using nonionic alkylamines and N,N-dimethylalkylamines (SO) as structure-directing agents in acidic conditions. The synthesized mesostructures possess wormhole-like frameworks with pore sizes and pore volumes in the range of 20-90 Angstrom and 0.5-1.3 cm(3)/g, respectively. The formation of the mesophase is controlled by a counterion-mediated mechanism of the type (S(0)H(+))(X(-)I(+)), where S(0)H(+) are protonated water molecules that are hydrogen bonded to the lone electron pairs on the amine surfactant headgroups (S(0)H(+)), X(-) is the counteranion originating from the acid, and I(+) are the positively charged (protonated) silicate species. We found that the stronger the ion X(-) is bonded to S(0)H(+), the more it catalyzes the silica condensation into (S(0)H(+))(X(-)I(+)). Br(-) is shown to be a strong binding anion and therefore a fast silica polymerization promoter compared to Cl(-) resulting in the formation of a higher quality mesophase for the Br(-) syntheses. We also showed that the polymerization rate of the silica, dictated by the counterion, controls the morphology of the mesostructures from nonuniform agglomerated blocks in the case of Br(-) syntheses to spherical particles for the Cl(-) syntheses. Next to many benefits such as low temperature, short synthesis time, and the use of inexpensive, nontoxic, and easily extractable amine templates, the developed materials have a remarkable higher thermal and hydrothermal stability compared to hexagonal mesoporous silica, which is also prepared with nonionic amines but formed through the S(0)I(0) mechanism.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Washington, D.C. Editor
  Language Wos 000182350200005 Publication Date 2003-04-17
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1520-6106;1520-5207; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 3.177 Times cited 9 Open Access
  Notes Approved Most recent IF: 3.177; 2003 IF: 3.679
  Call Number UA @ lucian @ c:irua:103300 Serial 24
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Author Chang, K.; Xia, J.B.; Peeters, F.M.
  Title Magnetic field tuning of the effective g factor in a diluted magnetic semiconductor quantum dot Type A1 Journal article
  Year 2003 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
  Volume 82 Issue 16 Pages 2661-2663
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract The spin interaction and the effective g factor of a magnetic exciton (ME) are investigated theoretically in a diluted magnetic semiconductor (DMS) quantum dot (QD), including the Coulomb interaction and the sp-d exchange interaction. At low magnetic field, the ME energy decreases rapidly with increasing magnetic field and saturates at high magnetic field for high Mn concentration. The ground state of the ME exhibits an interesting crossing behavior between sigma(+)-ME and sigma(-)-ME for low Mn concentration. The g(ex) factor of the ME in a DMS QD displays a monotonic decrease with increasing magnetic field and can be tuned to zero by an external magnetic field. (C) 2003 American Institute of Physics.
  Address
  Corporate Author Thesis
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
  Language Wos 000182258800037 Publication Date 2003-04-17
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0003-6951; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 3.411 Times cited 56 Open Access
  Notes Approved Most recent IF: 3.411; 2003 IF: 4.049
  Call Number UA @ lucian @ c:irua:103301 Serial 1878
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Author Ivanov, V.A.; Krstajic, P.M.; Peeters, F.M.; Fleurov, V.; Kikoin, K.
  Title On the nature of ferromagnetism in dilute magnetic semiconductors : GaAs:Mn and GaP:Mn Type A1 Journal article
  Year 2003 Publication Journal of magnetism and magnetic materials T2 – 2nd Moscow International Symposium on Magnetism (MISM 2001), JUN 20-24, 2001, MOSCOW STATE UNIV, MOSCOW, RUSSIA Abbreviated Journal J Magn Magn Mater
  Volume 258 Issue Pages 237-240
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  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.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Amsterdam Editor
  Language Wos 000181702000062 Publication Date 2003-03-25
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0304-8853; ISBN Additional Links (up) UA library record; WoS full record; WoS citing articles
  Impact Factor 2.63 Times cited 10 Open Access
  Notes Approved Most recent IF: 2.63; 2003 IF: 0.910
  Call Number UA @ lucian @ c:irua:103311 Serial 2442
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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 (up) 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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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 (up) 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 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 (up) 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 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 (up) 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 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 (up) 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 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 (up) 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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