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	Author	Kuznetsov, A.S.; Lu, Y.-G.; Turner, S.; Shestakov, M.V.; Tikhomirov, V.K.; Kirilenko, D.; Verbeeck, J.; Baranov, A.N.; Moshchalkov, V.V.
	Title	Preparation, structural and optical characterization of nanocrystalline ZnO doped with luminescent Ag-nanoclusters			Type	A1 Journal article
	Year	2012	Publication	Optical materials express	Abbreviated Journal	Opt Mater Express
	Volume	2	Issue	6	Pages	723-734
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Nanocrystalline ZnO doped with Ag-nanoclusters has been synthesized by a salt solid state reaction. Three overlapping broad emission bands due to the Ag nanoclusters have been detected at about 570, 750 and 900 nm. These emission bands are excited by an energy transfer from the exciton state of the ZnO host when pumped in the wavelength range from 250 to 400 nm. The 900 nm emission band shows characteristic orbital splitting into three components pointing out that the anisotropic crystalline wurtzite host of ZnO is responsible for this feature. Heat-treatment and temperature dependence studies confirm the origin of these emission bands. An energy level diagram for the emission process and a model for Ag nanoclusters sites are suggested. The emission of nanocrystalline ZnO doped with Ag nanoclusters may be applied for white light generation, displays driven by UV light, down-convertors for solar cells and luminescent lamps.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000304953700004	Publication Date	2012-04-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	2159-3930;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.591	Times cited		Open Access
	Notes	We are grateful to the Methusalem Funding of Flemish Government for the support of this work. Y.-G. L. and S. T. acknowledge funding from the Fund for Scientific Research Flanders (FWO) for a postdoctoral grant and under grant number G056810N. The microscope used in this study was partially financed by the Hercules Foundation. J.V. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC grant No246791 – COUNTATOMS and ERC Starting Grant 278510 VORTEX. The authors acknowledge the guidance of Prof. G. Van Tendeloo, EMAT Antwerpen University, in transmission electron microscopy study in this work. ECASJO_;			Approved	Most recent IF: 2.591; 2012 IF: 2.616
	Call Number	UA @ lucian @ c:irua:97709UA @ admin @ c:irua:97709			Serial	2707
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	Author	Navío, C.; Vallejos, S.; Stoycheva, T.; Llobet, E.; Correig, X.; Snyders, R.; Blackman, C.; Umek, P.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.;
	Title	Gold clusters on WO₃ nanoneedles grown via AACVD : XPS and TEM studies			Type	A1 Journal article
	Year	2012	Publication	Materials chemistry and physics	Abbreviated Journal	Mater Chem Phys
	Volume	134	Issue	2/3	Pages	809-813
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	We have prepared tungsten oxide films decorated with gold particles on Si substrates by aerosol assisted chemical vapor deposition (AACVD) and characterized them using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). SEM shows that the films are composed of needle-like structures and TEM shows that both the needles and the gold particles are crystalline. XPS indicates the presence of oxygen vacancies, i.e. the films are WO3−x, and hence the deposited material is composed of semiconducting nanostructures and that the interaction between the gold particles and the WO3 needles surface is weak. The synthesis of semiconducting tungsten oxide nanostructures decorated with metal particles represents an important step towards the development of sensing devices with optimal properties.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Lausanne	Editor
	Language		Wos	000305918200038	Publication Date	2012-04-30
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0254-0584;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.084	Times cited	52	Open Access
	Notes	Iap			Approved	Most recent IF: 2.084; 2012 IF: 2.072
	Call Number	UA @ lucian @ c:irua:97705			Serial	1356
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	Author	Turner, S.; Verbeeck, J.; Ramezanipour, F.; Greedan, J.E.; Van Tendeloo, G.; Botton, G.A.
	Title	Atomic resolution coordination mapping in Ca₂FeCoO₅ brownmillerite by spatially resolved electron energy-loss spectroscopy			Type	A1 Journal article
	Year	2012	Publication	Chemistry of materials	Abbreviated Journal	Chem Mater
	Volume	24	Issue	10	Pages	1904-1909
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Using a combination of high-angle annular dark field scanning transmission electron microscopy and atomically resolved electron energy-loss spectroscopy at high energy resolution in an aberration-corrected electron microscope, we demonstrate the capability of coordination mapping in complex oxides. Brownmillerite compound Ca2FeCoO5, consisting of repetitive octahedral and tetrahedral coordination layers with Fe and Co in a fixed 3+ valency, is selected to demonstrate the principle of atomic resolution coordination mapping. Analysis of the Co-L2,3 and the Fe-L2,3 edges shows small variations in the fine structure that can be specifically attributed to Co/Fe in tetrahedral or in octahedral coordination. Using internal reference spectra, we show that the coordination of the Fe and Co atoms in the compound can be mapped at atomic resolution.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000304237500024	Publication Date	2012-04-25
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0897-4756;1520-5002;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	9.466	Times cited	33	Open Access
	Notes	A.M. Abakumov is thanked for fruitful discussions. S.T. gratefully acknowledges the Fund for Scientific Research Flanders (FWO). J.E.G. and GAB. acknowledge the support of the NSERC of Canada through Discovery Grants. The Canadian Centre for Electron Microscopy is a National Facility supported by NSERC and McMaster University and was funded by the Canada Foundation for Innovation and the Ontario Government. Part of this work was supported by funding from the European Research Council under the FP7, ERC Grant N 246791 COUNTATOMS and ERC Starting Grant N 278510 VORTEX. The EMAT microscope is partially funded by the Hercules fund of the Flemish Government. ECASJO_;			Approved	Most recent IF: 9.466; 2012 IF: 8.238
	Call Number	UA @ lucian @ c:irua:98379UA @ admin @ c:irua:98379			Serial	175
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	Author	Govaerts, K.; Sluiter, M.H.F.; Partoens, B.; Lamoen, D.
	Title	Stability of Sb-Te layered structures : first-principles study			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	14	Pages	144114-144114,8
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	Using an effective one-dimensional cluster expansion in combination with first-principles electronic structure calculations we have studied the energetics and electronic properties of Sb-Te layered systems. For a Te concentration between 0 and 60 at. % an almost continuous series of metastable structures is obtained consisting of consecutive Sb bilayers next to consecutive Sb2Te3 units, with the general formula (Sb-2)(n)(Sb2Te3)(m) (n, m = 1,2, ... ). Between 60 and 100 at.% no stable structures are found. We account explicitly for the weak van derWaals bonding between Sb bilayers and Sb2Te3 units by using a recently developed functional, which strongly improves the interlayer bonding distances. At T = 0 K, no evidence is found for the existence of two separate single-phase regions delta and gamma and a two-phase region delta + gamma. Metastable compounds with a Te concentration between 0 and 40 at. % are semimetallic, whereas compounds with a Te concentration between 50 and 60 at. % are semiconducting. Compounds with an odd number of Sb layers are metallic and have a much higher formation energy than those with an even number of consecutive Sb layers, thereby favoring the formation of Sb bilayers.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000303115400004	Publication Date	2012-04-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	14	Open Access
	Notes	Iwt; Fwo			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:98255			Serial	3129
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	Author	Shakouri, K.; Szafran, B.; Esmaeilzadeh, M.; Peeters, F.M.
	Title	Effective spin-orbit interaction Hamiltonian for quasi-one-dimensional quantum rings			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	16	Pages	165314-165314,8
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The effective Hamiltonian for an electron in a quasi-one-dimensional quantum ring in the presence of spin-orbit interactions is derived. We demonstrate that, when both coupling types are simultaneously present, the effective Hamiltonian derived by the lowest-radial-state approximation produces energy spectra and charge densities which deviate strongly from the exact ones. For equal Rashba and Dresselhaus coupling constants the lowest-radial-state approximation opens artifactal avoided crossings in the energy spectra and deforms the circular symmetry of the confined charge densities. In this case, there does not exist a ring thin enough to justify the restriction to the lowest radially quantized energy state. We derive the effective Hamiltonian accounting for both the lowest and the first excited radial states, and show that the inclusion of the latter restores the correct features of the exact solution. Relation of this result to the states of a quantum wire is also discussed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000303068800006	Publication Date	2012-04-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	32	Open Access
	Notes	; This work was partially supported by Polish Ministry of Science and Higher Education and its grants for Scientific Research. ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:98258			Serial	855
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	Author	Schattschneider, P.; Schaffer, B.; Ennen, I.; Verbeeck, J.
	Title	Mapping spin-polarized transitions with atomic resolution			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	13	Pages	134422-134422,8
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The coupling of angstrom-sized electron probes with spin-polarized electronic transitions shows that the inelastically scattered probe electron is in a mixed state containing electron vortices with nonzero orbital angular momentum. These electrons create an asymmetric intensity distribution in energy filtered diffraction patterns, giving access to maps of the magnetic moments with atomic resolution. A feasibility experiment shows evidence of the predicted effect. Potential applications are column-by-column maps of magnetic ordering, and the creation of angstrom-sized free electrons with orbital angular momentum by inelastic scattering in a thin ferromagnetic foil.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000302608100004	Publication Date	2012-04-11
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	41	Open Access
	Notes	The authors thank A. Bleloch, S. Loffler, and P. Nellist for fruitful discussions and suggestions. P.S. acknowledges financial support from the Austrian Science Fund, Project No. I543-N20. The support of the EPSRC for the SuperSTEM facility is gratefully acknowledged. J.V. acknowledges support from the European Research Council under the 7th Framework Program (FP7), ERC Grant No. 246791-COUNTATOMS and ERC Starting Grant No. 278510-VORTEX. ECASJO_;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:97390UA @ admin @ c:irua:97390			Serial	1945
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	Author	Clem, J.R.; Mawatari, Y.; Berdiyorov, G.R.; Peeters, F.M.
	Title	Predicted field-dependent increase of critical currents in asymmetric superconducting nanocircuits			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	14	Pages	144511-144511,16
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The critical current of a thin superconducting strip of width W much larger than the Ginzburg-Landau coherence length xi but much smaller than the Pearl length Lambda = 2 lambda(2)/d is maximized when the strip is straight with defect-free edges. When a perpendicular magnetic field is applied to a long straight strip, the critical current initially decreases linearly with H but then decreases more slowly with H when vortices or antivortices are forced into the strip. However, in a superconducting strip containing sharp 90 degrees or 180 degrees turns, the zero-field critical current at H = 0 is reduced because vortices or antivortices are preferentially nucleated at the inner corners of the turns, where current crowding occurs. Using both analytic London-model calculations and time-dependent Ginzburg-Landau simulations, we predict that in such asymmetric strips the resulting critical current can be increased by applying a perpendicular magnetic field that induces a current-density contribution opposing the applied current density at the inner corners. This effect should apply to all turns that bend in the same direction.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000302611100004	Publication Date	2012-04-10
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	40	Open Access
	Notes	; This research, supported in part by the US Department of Energy, Office of Basic Energy Science, Division of Materials Sciences and Engineering, was performed in part at the Ames Laboratory, which is operated for the US Department of Energy by Iowa State University under Contract No. DE-AC02-07CH11358. This work also was supported in part by the Flemish Science Foundation (FWO-Vlaanderen) and the Belgian Science Policy (IAP). G.R.B. acknowledges individual support from FWO-Vlaanderen. ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:98263			Serial	2695
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	Author	Simon, Q.; Barreca, D.; Gasparotto, A.; Maccato, C.; Montini, T.; Gombac, V.; Fornasiero, P.; Lebedev, O.I.; Turner, S.; Van Tendeloo, G.
	Title	Vertically oriented CuO/ZnO nanorod arrays : from plasma-assisted synthesis to photocatalytic H₂ production			Type	A1 Journal article
	Year	2012	Publication	Journal of materials chemistry	Abbreviated Journal	J Mater Chem
	Volume	22	Issue	23	Pages	11739-11747
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	1D CuO/ZnO nanocomposites were grown on Si(100) substrates by means of an original two-step synthetic strategy. ZnO nanorod (NR) arrays were initially deposited by plasma enhanced-chemical vapor deposition (PE-CVD) from an ArO2 atmosphere. Subsequently, tailored amounts of CuO were dispersed over zinc oxide matrices by radio frequency (RF)-sputtering of Cu from Ar plasmas, followed by thermal treatment in air. A thorough characterization of the obtained systems was carried out by X-ray photoelectron and X-ray excited-Auger electron spectroscopies (XPS and XE-AES), glancing incidence X-ray diffraction (GIXRD), field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDXS), atomic force microscopy (AFM), transmission electron microscopy (TEM), electron diffraction (ED) and energy filtered-TEM (EF-TEM). Pure and highly oriented CuO/ZnO NR arrays, free from ternary ZnCuO phases and characterized by a copper(II) oxide content controllable as a function of the adopted RF-power, were successfully obtained. Interestingly, the structural relationships between the two oxides at the CuO/ZnO interface were found to depend on the overall CuO loading. The obtained nanocomposites displayed promising photocatalytic performances in H2 production by reforming of ethanolwater solutions under simulated solar illumination, paving the way to the sustainable conversion of solar light into chemical energy.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Cambridge	Editor
	Language		Wos	000304351400046	Publication Date	2012-04-05
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0959-9428;1364-5501;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	74	Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:98382			Serial	3840
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	Author	Mees, M.J.; Pourtois, G.; Neyts, E.C.; Thijsse, B.J.; Stesmans, A.
	Title	Uniform-acceptance force-bias Monte Carlo method with time scale to study solid-state diffusion			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	13	Pages	134301-134301,9
	Keywords	A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Monte Carlo (MC) methods have a long-standing history as partners of molecular dynamics (MD) to simulate the evolution of materials at the atomic scale. Among these techniques, the uniform-acceptance force-bias Monte Carlo (UFMC) method [ G. Dereli Mol. Simul. 8 351 (1992)] has recently attracted attention [ M. Timonova et al. Phys. Rev. B 81 144107 (2010)] thanks to its apparent capacity of being able to simulate physical processes in a reduced number of iterations compared to classical MD methods. The origin of this efficiency remains, however, unclear. In this work we derive a UFMC method starting from basic thermodynamic principles, which leads to an intuitive and unambiguous formalism. The approach includes a statistically relevant time step per Monte Carlo iteration, showing a significant speed-up compared to MD simulations. This time-stamped force-bias Monte Carlo (tfMC) formalism is tested on both simple one-dimensional and three-dimensional systems. Both test-cases give excellent results in agreement with analytical solutions and literature reports. The inclusion of a time scale, the simplicity of the method, and the enhancement of the time step compared to classical MD methods make this method very appealing for studying the dynamics of many-particle systems.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000302290500001	Publication Date	2012-04-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	31	Open Access
	Notes				Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:97160			Serial	3809
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	Author	Saniz, R.; Partoens, B.; Peeters, F.M.
	Title	Green function approach to superconductivity in nanowires			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	14	Pages	144504-144504,7
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	Superconductivity in nanowires made of weak coupling superconductor materials is investigated using a Green function approach. We show that these are multigap systems in which the ratio Delta(T)/k(B)T(c) is to a large extent similar to what is observed in some high-T-c two-gap systems, such as MgB2 and some of the Fe-based superconductors. On the other hand, because of confinement, the superfluid density has a temperature behavior of the form n(s)(T) = 1 – (T/T-c)(3) near T-c, thus deviating from the BCS behavior for bulk superconductors.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000302290700006	Publication Date	2012-04-03
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	1	Open Access
	Notes	; This work was supported by FWO-Vl and the Belgian Science Policy (IAP). ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:97764			Serial	1381
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	Author	Dixon, E.; Hadermann, J.; Hayward, M.A.
	Title	Structures and magnetism of La_1-xSr_xMnO_3-(0.5+x)/2 (0.67\leq x\leq1) phases			Type	A1 Journal article
	Year	2012	Publication	Chemistry of materials	Abbreviated Journal	Chem Mater
	Volume	24	Issue	8	Pages	1486-1495
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Topotactic reduction of La1-xSrxMnO3 (0.67 <= x <= 1) phases with sodium hydride yields a series of isoelectronic materials of composition La1-xSrxMnO3-(0.5+x)/2. Lanthanum rich members of the series (0.67 <= x <= 0.83) adopt anion deficient perovskite structures with a 6-layer -OTOOT'O- stacking sequence of sheets of octahedra/square-based pyramids (O) and sheets of tetrahedra (T). The strontium rich members of the series (0.83 <= x <= 1) incorporate “step defects” into this 6-layer structure in which the OTOOT'O stacking sequence is converted into either OOTOOT' or TOOT'OO at a defect plane which runs perpendicular to the [201] lattice plane. The step defects appear to provide a mechanism to relieve lattice strain and accommodate additional anion deficiency in phases with x > 0.83. Magnetization and neutron diffraction data indicate La1-xSrxMnO3-(0.5+x)/2 phases adopt antiferromagnetically ordered states at low-temperature in which the ordered arrangement of magnetic spins is incommensurate with the crystallographic lattice.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000303092300011	Publication Date	2012-03-28
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0897-4756;1520-5002;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	9.466	Times cited	13	Open Access
	Notes	Esteem 026019			Approved	Most recent IF: 9.466; 2012 IF: 8.238
	Call Number	UA @ lucian @ c:irua:98253			Serial	3318
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	Author	Khalilov, U.; Pourtois, G.; van Duin, A.C.T.; Neyts, E.C.
	Title	Hyperthermal oxidation of Si(100)2x1 surfaces : effect of growth temperature			Type	A1 Journal article
	Year	2012	Publication	The journal of physical chemistry: C : nanomaterials and interfaces	Abbreviated Journal	J Phys Chem C
	Volume	116	Issue	15	Pages	8649-8656
	Keywords	A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
	Abstract	Using reactive molecular dynamics simulations based on the ReaxFF potential, we studied the growth mechanism of ultrathin silica (SiO2) layers during hyperthermal oxidation as a function of temperature in the range 100-1300 K. Oxidation of Si(100){2 x 1} surfaces by both atomic and molecular oxygen was investigated for hyperthermal impact energies in the range of 1 to 5 eV. Two different growth mechanisms are found, corresponding to a low temperature oxidation and a high temperature one. The transition temperature between these mechanisms is estimated to be about 700 K. Also, the initial step of the Si oxidation process is analyzed in detail. Where possible, we validated our results with experimental and ab initio data, and good agreement was obtained. This study is important for the fabrication of silica-based devices in the micro- and nanoelectronics industry and, more specifically, for the fabrication of metal oxide semiconductor devices.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000302924900035	Publication Date	2012-03-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1932-7447;1932-7455;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.536	Times cited	32	Open Access
	Notes				Approved	Most recent IF: 4.536; 2012 IF: 4.814
	Call Number	UA @ lucian @ c:irua:98259			Serial	1542
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	Author	Boschker, H.; Verbeeck, J.; Egoavil, R.; Bals, S.; Van Tendeloo, G.; Huijben, M.; Houwman, E.P.; Koster, G.; Blank, D.H.A.; Rijnders, G.
	Title	Preventing the reconstruction of the polar discontinuity at oxide heterointerfaces			Type	A1 Journal article
	Year	2012	Publication	Advanced functional materials	Abbreviated Journal	Adv Funct Mater
	Volume	22	Issue	11	Pages	2235-2240
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Perovskite oxide heteroepitaxy receives much attention because of the possibility to combine the diverse functionalities of perovskite oxide building blocks. A general boundary condition for the epitaxy is the presence of polar discontinuities at heterointerfaces. These polar discontinuities result in reconstructions, often creating new functionalities at the interface. However, for a significant number of materials these reconstructions are unwanted as they alter the intrinsic materials properties at the interface. Therefore, a strategy to eliminate this reconstruction of the polar discontinuity at the interfaces is required. We show that the use of compositional interface engineering can prevent the reconstruction at the La0.67Sr0.33MnO3/SrTiO3 (LSMO/STO) interface. The polar discontinuity at this interface can be removed by the insertion of a single La0.33Sr0.67O layer, resulting in improved interface magnetization and electrical conductivity.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Weinheim	Editor
	Language		Wos	000304749600002	Publication Date	2012-03-23
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1616-301X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	12.124	Times cited	72	Open Access
	Notes	We wish to acknowledge the financial support of the Dutch Science Foundation (NWO) and the Dutch Nanotechnology program NanoNed. S. B. acknowledges the financial support from the European Union under the Framework 6 program under a contract for an Integrated Infrastructure Initiative. Reference 026019 ESTEEM. J. V. and G. V. T. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC grant N246791 – COUNTATOMS. R. E. acknowledges funding by the European Union Council under the 7th Framework Program (FP7) grant NNMP3-LA-2010-246102 IFOX. We thank Sandra Van Aert for stimulating discussions.			Approved	Most recent IF: 12.124; 2012 IF: 9.765
	Call Number	UA @ lucian @ c:irua:98907UA @ admin @ c:irua:98907			Serial	2712
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	Author	Savchenko, D.V.; Serdan, A.A.; Morozov, V.A.; Van Tendeloo, G.; Ionov, S.G.
	Title	Improvement of the oxidation stability and the mechanical properties of flexible graphite foil by boron oxide impregnation			Type	A1 Journal article
	Year	2012	Publication	New carbon materials	Abbreviated Journal
	Volume	27	Issue	1	Pages	12-18
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Flexible graphite foil produced by rolling expanded graphite impregnated with boron oxide was analyzed by laser mass spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and thermogravimetry. It was shown that the modification of the graphite foil by boron oxide increases the onset temperature of oxidation by ∼ 150 °C. Impregnation of less than 2 mass% boron oxide also increased the tensile strength of the materials. The observed improvement was attributed to the blocking of active sites by boron oxide, which is probably chemically bonded to the edges of graphene sheets in expanded graphite particles.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000304742100002	Publication Date	2012-03-21
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1872-5805;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	5	Open Access
	Notes	Iap			Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:96958			Serial	1569
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	Author	Narayanan, V.; Lommens, P.; De Buysser, K.; Vanpoucke, D.E.P.; Huehne, R.; Molina, L.; Van Tendeloo, G.; van der Voort, P.; Van Driessche, I.
	Title	Aqueous CSD approach for the growth of novel, lattice-tuned La_xCe_1-xO_\delta epitaxial layers			Type	A1 Journal article
	Year	2012	Publication	Journal of materials chemistry	Abbreviated Journal	J Mater Chem
	Volume	22	Issue	17	Pages	8476-8483
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Lanthanumcerium oxide (LCO) films were deposited on Ni-5%W substrates by chemical solution deposition (CSD) from water-based precursors. LCO films containing different ratios of lanthanum and cerium ions (from CeO2 to La2Ce2O7) were prepared. The composition of the layers was optimized towards the formation of LCO buffer layers, lattice-matched with the superconducting YBa2Cu3Oy layer, useful for the development of coated conductors. Single, crack-free LCO layers with a thickness of up to 140 nm could be obtained in a single deposition step. The crystallinity and microstructure of these lattice-matched LCO layers were studied by X-ray diffraction techniques, RHEED and SEM. We find that only layers with thickness below 100 nm show a crystalline top surface although both thick and thin layers show good biaxial texture in XRD. On the most promising layers, AFM and (S)TEM were performed to further evaluate their morphology. The overall surface roughness varies between 3.9 and 7.5 nm, while the layers appear much more dense than the frequently used La2Zr2O7 (LZO) systems, showing much smaller nanovoids (12 nm) than the latter system. Their effective buffer layer action was studied using XPS. The thin LCO layers supported the growth of superconducting YBCO deposited using PLD methods.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Cambridge	Editor
	Language		Wos	000302367500044	Publication Date	2012-03-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0959-9428;1364-5501;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor		Times cited	24	Open Access
	Notes	Iap			Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:96960			Serial	148
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	Author	Michel, K.H.; Verberck, B.
	Title	Theory of rigid-plane phonon modes in layered crystals			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	9	Pages	094303-094303,11
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The lattice dynamics of low-frequency rigid-plane modes in metallic (graphene multilayers, GML) and in insulating (hexagonal boron-nitride multilayers, BNML) layered crystals is investigated. The frequencies of shearing and compression (stretching) modes depend on the layer number N and are presented in the form of fan diagrams. The results for GML and BNML are very similar. In both cases, only the interactions (van der Waals and Coulomb) between nearest-neighbor planes are effective, while the interactions between more distant planes are screened. A comparison with recent Raman scattering results on low-frequency shear modes in GML [Tan et al., Nat. Mater., in press, doi: 10.1038/nmat3245, (2012)] is made. Relations with the low-lying rigid-plane phonon dispersions in the bulk materials are established. Master curves, which connect the fan diagram frequencies for any given N, are derived. Static and dynamic thermal correlation functions for rigid-layer shear and compression modes are calculated. The results might be of use for the interpretation of friction force experiments on multilayer crystals.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000301646000006	Publication Date	2012-03-19
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	38	Open Access
	Notes	; The authors are indebted to J. Maultzsch for bringing Ref. 20 to their attention. They thank D. Lamoen, F.M. Peeters, B. Trauzettel, and C. Van Haesendonck for useful discussions. This work has been financially supported by the Research Foundation Flanders (FWO). ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:97787			Serial	3619
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	Author	Angelomé, P.C.; Heidari Mezerji, H.; Goris, B.; Pastoriza-Santos, I.; Pérez-Juste, J.; Bals, S.; Liz-Marzán, L.M.
	Title	Seedless synthesis of single crystalline Au nanoparticles with unusual shapes and tunable LSPR in the near-IR			Type	A1 Journal article
	Year	2012	Publication	Chemistry of materials	Abbreviated Journal	Chem Mater
	Volume	24	Issue	7	Pages	1393-1399
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The plasmonic properties of metal nanoparticles have acquired great importance because of their potential applications in very diverse fields. Metal nanoparticles with localized surface plasmon resonances (LSPR) in the near-infrared (NIR, 7501300 nm) are of particular interest because tissues, blood, and water display low absorption in this spectral range, thus facilitating biomedical applications. Cetyltrimethylammonium chloride (CTAC) was used to induce the seedless formation of highly anisotropic, twisted single crystalline Au nanoparticles in a single step. The LSPR of the obtained particles can be tuned from 600 nm up to 1400 nm by simply changing the reaction temperature or the reagents concentrations. The tunability of the LSPR is closely associated with significant changes in the final particle morphology, which was studied by advanced electron microscopy techniques (3D Tomography and HAADF-STEM). Kinetic experiments were carried out to establish the growth mechanism, suggesting that slow kinetics together with the complexation of the gold salt precursor to CTAC are key factors favoring the formation of these anisotropic particles.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000302487500020	Publication Date	2012-03-16
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0897-4756;1520-5002;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	9.466	Times cited	42	Open Access
	Notes	Fwo			Approved	Most recent IF: 9.466; 2012 IF: 8.238
	Call Number	UA @ lucian @ c:irua:97388			Serial	2959
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	Author	Dachraoui, W.; Hadermann, J.; Abakumov, A.M.; Tsirlin, A.A.; Batuk, D.; Glazyrin, K.; McCammon, C.; Dubrovinsky, L.; Van Tendeloo, G.
	Title	Local oxygen-vacancy ordering and twinned octahedral tilting pattern in the Bi_0.81Pb_0.19FeO_2.905 cubic perovskite			Type	A1 Journal article
	Year	2012	Publication	Chemistry of materials	Abbreviated Journal	Chem Mater
	Volume	24	Issue	7	Pages	1378-1385
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The structure of Bi0.81Pb0.19FeO2.905 was investigated on different length scales using a combination of electron diffraction, high-resolution scanning transmission electron microscopy, synchrotron X-ray powder diffraction, and Mössbauer spectroscopy. In the 80300 K temperature range, the average crystal structure of Bi0.81Pb0.19FeO2.905 is a cubic Pm3̅m perovskite with a = 3.95368(3) Å at T = 300 K. The (Pb2+, Bi3+) cations and O2 anions are randomly displaced along the 110 cubic directions, indicating the steric activity of the lone pair on the Pb2+ and Bi3+ cations and a tilting distortion of the perovskite framework. The charge imbalance induced by the heterovalent Bi3+ → Pb2+ substitution is compensated by the formation of oxygen vacancies preserving the trivalent state of the Fe cations. On a short scale, oxygen vacancies are located in anion-deficient (FeO1.25) layers that are approximately 6 perovskite unit cells apart and transform every sixth layer of the FeO6 octahedra into a layer with a 1:1 mixture of corner-sharing FeO4 tetrahedra and FeO5 tetragonal pyramids. The anion-deficient layers act as twin planes for the octahedral tilting pattern of adjacent perovskite blocks. They effectively randomize the octahedral tilting and prevent the cooperative distortion of the perovskite framework. The disorder in the anion sublattice impedes cooperative interactions of the local dipoles induced by the off-center displacements of the Pb and Bi cations. Magnetic susceptibility measurements evidence the antiferromagnetic ordering in Bi0.81Pb0.19FeO2.905 at low temperatures.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000302487500018	Publication Date	2012-03-13
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0897-4756;1520-5002;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	9.466	Times cited	27	Open Access
	Notes				Approved	Most recent IF: 9.466; 2012 IF: 8.238
	Call Number	UA @ lucian @ c:irua:97389			Serial	1829
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	Author	Berdiyorov, G.R.; Hernández-Nieves, A.D.; Milošević, M.V.; Peeters, F.M.; Dominguez, D.
	Title	Flux-quantum-discretized dynamics of magnetic flux entry, exit, and annihilation in current-driven mesoscopic type-I superconductors			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	9	Pages	092502-092502,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We study nonlinear flux dynamics in a current-carrying type-I superconductor. The stray magnetic field of the current induces the intermediate state, where nucleation of flux domains is discretized to a single fluxoid at a time, while their final shape (tubular or laminar), size, and nucleation rate depend on applied current and edge conditions. The current induces opposite flux domains on opposite sides of the sample, and subsequently drives them to annihilation-which is also discretized, as a sequence of vortex-antivortex pairs. The discretization of both nucleation and annihilation leaves measurable traces in the voltage across the sample and in locally probed magnetization. The reported dynamic phenomena thus provide an unambiguous proof of a flux quantum being the smallest building block of the intermediate state in type-I superconductors.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000301183000002	Publication Date	2012-03-07
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	14	Open Access
	Notes	; This work was supported by the Belgian Science Policy (IAP), the Flemish Science Foundation (FWO-Vl), and the collaborative project FWO-MINCyT (Project No. FW/08/01). G. R. B. and A. D. H acknowledge support from FWO-Vl. A. D. H. and D. D. acknowledge support from CONICET, CNEA, and ANPCyT (Grant No. PICT07-824). ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:97180			Serial	1243
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	Author	Verberck, B.; Partoens, B.; Peeters, F.M.; Trauzettel, B.
	Title	Strain-induced band gaps in bilayer graphene			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	12	Pages	125403-125403,10
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	We present a tight-binding investigation of strained bilayer graphene within linear elasticity theory, focusing on the different environments experienced by the A and B carbon atoms of the different sublattices. We find that the inequivalence of the A and B atoms is enhanced by the application of perpendicular strain epsilon(zz), which provides a physical mechanism for opening a band gap, most effectively obtained when pulling the two graphene layers apart. In addition, perpendicular strain introduces electron-hole asymmetry and can result in linear electronic dispersion near the K point. Our findings suggest experimental means for strain-engineered band gaps in bilayer graphene.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000301113200005	Publication Date	2012-03-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	53	Open Access
	Notes	; The authors would like to acknowledge O. Leenaerts, E. Mariani, K. H. Michel, and J. Schelter for useful discussions. B. V. was financially supported by the Flemish Science Foundation (FWO-Vl). This work was financially supported by the ESF program EuroGraphene under projects CONGRAN and ENTS as well as by the DFG. ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:97181			Serial	3168
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	Author	Fang, C.M.; van Huis, M.A.; Thijsse, B.J.; Zandbergen, H.W.
	Title	Stability and crystal structures of iron carbides : a comparison between the semi-empirical modified embedded atom method and quantum-mechanical DFT calculations			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	5	Pages	054116-054116,7
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Iron carbides play a crucial role in steel manufacturing and processing and to a large extent determine the physical properties of steel products. The modified embedded atom method (MEAM) in combination with Lee's Fe-C potential is a good candidate for molecular dynamics simulations on larger Fe-C systems. Here, we investigate the stability and crystal structures of pure iron and binary iron carbides using MEAM and compare them with the experimental data and quantum-mechanical density functional theory calculations. The analysis shows that the Fe-C potential gives reasonable results for the relative stability of iron and iron carbides. The performance of MEAM for the prediction of the potential energy and the calculated lattice parameters at elevated temperature for pure iron phases and cementite are investigated as well. The conclusion is that Lee's MEAM Fe-C potential provides a promising basis for further molecular dynamics simulations of Fe-C alloys and steels at lower temperatures (up to 800 K).
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000300931900004	Publication Date	2012-02-29
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	18	Open Access
	Notes				Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:97201			Serial	3117
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	Author	Krstajić, P.M.; Peeters, F.M.
	Title	Remote electron plasmon polaron in graphene			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	8	Pages	085436-085436,5
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The Coulomb interaction and the correlation of a remote electron with a single layer of graphene is investigated in the presence of a magnetic field applied perpendicular to the graphene layer. The remote electron polarizes the electron gas in the graphene layer, which we describe in terms of excitations of virtual plasmons in graphene. The composite quasiparticle formed by electron plus polarization is called a plasmon polaron. The ground-state energy of this quasiparticle is calculated within perturbation theory for remote electrons in different environments.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000300831900012	Publication Date	2012-02-27
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	4	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl). ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:97202			Serial	2869
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	Author	Nayuk, R.; Zacher, D.; Schweins, R.; Wiktor, C.; Fischer, R.A.; Van Tendeloo, G.; Huber, K.
	Title	Modulated formation of MOF-5 nanoparticles : a SANS analysis			Type	A1 Journal article
	Year	2012	Publication	The journal of physical chemistry: C : nanomaterials and interfaces	Abbreviated Journal	J Phys Chem C
	Volume	116	Issue	10	Pages	6127-6135
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	MOF-5 nanoparticles were prepared by mixing a solution of [Zn4O(C6H5COO)(6)] with a solution of benzene-1,4-dicarboxylic acid in DMF at ambient conditions. The former species mimics as a secondary building unit (SBU), and the latter acts as linker. Mixing of the two solutions induced the formation of MOF-5 nanoparticles in dilute suspension. The applied conditions were identified as suitable for a closer investigation of the particle formation process by combined light and small angle neutron scattering (SANS). Scattering analysis revealed a significant impact of the molar ratio of the two components in the reaction mixture. Excessive use of the building unit slowed down the process. A similar effect was observed upon addition of 4n-decylbenzoic acid, which is supposed to act as a modulator. The formation mechanism leads to initial intermediates, which turn into cubelike nanoparticles with a diameter of about 60-80 nm. This initial stage is followed by an extended formation period, where nucleation proceeds over hours, leading to an increasing number of nanoparticles with the same final size of 60-80 nm.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Washington, D.C.	Editor
	Language		Wos	000301509600020	Publication Date	2012-02-16
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1932-7447;1932-7455;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.536	Times cited	24	Open Access
	Notes				Approved	Most recent IF: 4.536; 2012 IF: 4.814
	Call Number	UA @ lucian @ c:irua:97789			Serial	2163
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	Author	Nasr Esfahani, D.; Covaci, L.; Peeters, F.M.
	Title	Electric-field-induced shift of the Mott metal-insulator transition in thin films			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	8	Pages	085110-085110,8
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The ground-state properties of a paramagnetic Mott insulator at half-filling are investigated in the presence of an external electric field using the inhomogeneous Gutzwiller approximation for a single-band Hubbard model in a slab geometry. We find that the metal-insulator transition is shifted toward higher Hubbard repulsions by applying an electric field perpendicular to the slab. The main reason is the accumulation of charges near the surface. The spatial distribution of site-dependent quasiparticle weight shows that it is maximal in a few layers beneath the surface, while the central sites where the field is screened have a very low quasiparticle weight. Our results show that above a critical-field value, states near the surface will be metallic, while the bulk quasiparticle weight is extremely suppressed but never vanishing, even for large Hubbard repulsions above the bulk zero-field critical value. Below the critical-field value, our results hint toward an insulating state in which the electric field is totally screened and the slab is again at half-filling.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000300240100002	Publication Date	2012-02-14
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	3	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen) and the Belgian Science Policy (IAP). ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:97208			Serial	884
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	Author	Ribbens, S.; Beyers, E.; Schellens, K.; Mertens, M.; Ke, X.; Bals, S.; Van Tendeloo, G.; Meynen, V.; Cool, P.
	Title	Systematic evaluation of thermal and mechanical stability of different commercial and synthetic photocatalysts in relation to their photocatalytic activity			Type	A1 Journal article
	Year	2012	Publication	Microporous and mesoporous materials: zeolites, clays, carbons and related materials	Abbreviated Journal	Micropor Mesopor Mat
	Volume	156	Issue		Pages	62-72
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
	Abstract	The effect of thermal treatment and mechanical stress on the structural and photocatalytic properties of eight different (synthetic and commercial) photocatalysts has been thoroughly investigated. Different mesoporous Ti-based materials were prepared via surfactant based synthesis routes (e.g. Pluronic 123, CTMABr = Cetyltrimethylammonium bromide) or via template-free synthesis routes (e.g. trititanate nanotubes). Also, the stabilizing effect of the NaOH/NH4OH post-treatment on the templated mesoporous materials and their photocatalytic activity was investigated. Furthermore, the thermal and mechanical properties of commercially available titanium dioxides such as P25 Evonik® and Millenium PC500® were studied. The various photocatalysts were analyzed with N2-sorption, X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA) to obtain information concerning the specific surface area, pore volume, crystal structure, morphology, phase transitions, etc. In general, results show that the NaOH post-treatment leads to an increased control of the crystallization process during calcination resulting in a higher thermal stability, but at the same time diminishes the photocatalytic activity. Mesoporous materials in which pre-synthesized nanoparticles are used as titania source have the best mechanical stability whereas the mechanical stability of the nanotubes is the most limited. At increased temperatures and pressures, the tested commercial titanium dioxides lose their superior photocatalytic activity caused by a decreased accessibility of the active sites. The observed changes in adsorption capacities and photocatalytic activities cannot be assigned to one single phenomenon. In this respect, it shows the need to define a general/standard method to compare different photocatalysts. Furthermore, it is shown that the photocatalytic properties do not necessarily deteriorate under thermal stress, but can be improved due to crystallization, even though the initial material is (partially) destroyed. It is shown that the usefulness of a specific type of photocatalyst strongly depends on the application and the temperature/pressure to which it needs to resist.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000303625200010	Publication Date	2012-02-08
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1387-1811;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.615	Times cited	8	Open Access
	Notes	Fwo			Approved	Most recent IF: 3.615; 2012 IF: 3.365
	Call Number	UA @ lucian @ c:irua:96910			Serial	3466
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	Author	Bourgeois, J.; Hervieu, M.; Poienar, M.; Abakumov, A.M.; Elkaïm, E.; Sougrati, M.T.; Porcher, F.; Damay, F.; Rouquette, J.; Van Tendeloo, G.; Maignan, A.; Haines, J.; Martin, C.;
	Title	Evidence of oxygen-dependent modulation in LuFe₂O₄			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	6	Pages	064102-064120,10
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	A polycrystalline sample of LuFe2O4 has been investigated by means of powder synchrotron x-ray and neutron diffraction and transmission electron microscopy (TEM), along with Mössbauer spectroscopy and transport and magnetic properties. A monoclinic distortion is unambiguously evidenced, and the crystal structure is refined in the monoclinic C2/m space group [aM = 5.9563(1) Å, bM = 3.4372(1) Å, cM = 8.6431(1) Å, β = 103.24(1)°]. Along with the previously reported modulations distinctive of the charge-ordering (CO) of the iron species, a new type of incommensurate order is observed, characterized by a vector q⃗1 = α1a⃗M* + γ1c⃗M* (with α1 ≅ 0.55, γ1 ≅ 0.13). In situ heating TEM observations from 300 to 773 K confirm that the satellites associated with q⃗1 vanish completely, only at a temperature significantly higher than the CO temperature. This incommensurate modulation has a displacive character and corresponds primarily to a transverse displacive modulation wave of the Lu cations position, as revealed by the high resolution, high angle annular dark field scanning TEM images and in agreement with synchrotron data refinements. Analyses of vacuum-annealed samples converge toward the hypothesis of a new ordering mechanism, associated with a tiny oxygen deviation from the O4 stoichiometry.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000299896900003	Publication Date	2012-02-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	24	Open Access
	Notes	Hercules			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:95042			Serial	1095
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	Author	Tikhomirov, V.K.; Rodríguez, V.D.; Méndez-Ramos, J.; del- Castillo, J.; Kirilenko, D.; Van Tendeloo, G.; Moshchalkov, V.V.
	Title	Optimizing Er/Yb ratio and content in Er-Yb co-doped glass-ceramics for enhancement of the up- and down-conversion luminescence			Type	A1 Journal article
	Year	2012	Publication	Solar energy materials and solar cells	Abbreviated Journal	Sol Energ Mat Sol C
	Volume	100	Issue		Pages	209-215
	Keywords	A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
	Abstract	Er3+Yb3+ co-doped transparent glass-ceramics with varying Er/Yb content and ratio have been prepared. High quantum yields for up- and down-conversion luminescence by energy transfer from Yb3+ to Er3+ and from Er3+ to Yb3+, respectively, have been detected and optimized with respect to the Er/Yb content and ratio, and proposed in particular for up- and down-conversion of solar spectrum for enhancement of the efficiency of solar cells. The rise and decay kinetics for the population of the excited levels of Er3+ and Yb3+ have been studied and fit. Based on these experimental data, the mechanisms for the energy transfers have been suggested with emphasis on the optimized Er/Yb content and ratio for enhancement of the efficiency of the Er3+↔Yb3+ energy transfers.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000303034700030	Publication Date	2012-02-04
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0927-0248;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	4.784	Times cited	66	Open Access
	Notes	Fwo			Approved	Most recent IF: 4.784; 2012 IF: 4.630
	Call Number	UA @ lucian @ c:irua:97392			Serial	2493
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	Author	Latimer, M.L.; Berdiyorov, G.R.; Xiao, Z.L.; Kwok, W.K.; Peeters, F.M.
	Title	Vortex interaction enhanced saturation number and caging effect in a superconducting film with a honeycomb array of nanoscale holes			Type	A1 Journal article
	Year	2012	Publication	Physical review : B : condensed matter and materials physics	Abbreviated Journal	Phys Rev B
	Volume	85	Issue	1	Pages	012505-012505,4
	Keywords	A1 Journal article; Condensed Matter Theory (CMT)
	Abstract	The electrical transport properties of a MoGe thin film with a honeycomb array of nanoscale holes are investigated. The critical current of the system shows nonmatching anomalies as a function of applied magnetic field, enabling us to distinguish between multiquanta vortices trapped in the holes and interstitial vortices located between the holes. The number of vortices trapped in each hole is found to be larger than the saturation number predicted for an isolated hole and shows a nonlinear field dependence, leading to the caging effect as predicted from the Ginzburg-Landau (GL) theory. Our experimental results are supplemented by numerical simulations based on the GL theory.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000299867200001	Publication Date	2012-01-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	1098-0121;1550-235X;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	3.836	Times cited	41	Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP) (theory) and by the US Department of Energy (DOE) Grant No. DE-FG02-06ER46334 (experiment). G. R. B. acknowledges an individual grant from FWO-Vl. W. K. K. acknowledges support from DOE BES under Contract No. DE-AC02-06CH11357, which also funds Argonne's Center for Nanoscale Materials (CNM), where the focused-ion-beam milling was performed. M.L.L was a recipient of the NIU/ANL Distinguished Graduate Fellowship. ;			Approved	Most recent IF: 3.836; 2012 IF: 3.767
	Call Number	UA @ lucian @ c:irua:96224			Serial	3866
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	Author	Lu, Y.-G.; Verbeeck, J.; Turner, S.; Hardy, A.; Janssens, S.D.; De Dobbelaere, C.; Wagner, P.; Van Bael, M.K.; Van Tendeloo, G.
	Title	Analytical TEM study of CVD diamond growth on TiO₂ sol-gel layers			Type	A1 Journal article
	Year	2012	Publication	Diamond and related materials	Abbreviated Journal	Diam Relat Mater
	Volume	23	Issue		Pages	93-99
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The early growth stages of chemical vapor deposition (CVD) diamond on a solgel TiO2 film with buried ultra dispersed diamond seeds (UDD) have been studied. In order to investigate the diamond growth mechanism and understand the role of the TiO2 layer in the growth process, high resolution transmission electron microscopy (HRTEM), energy-filtered TEM and electron energy loss spectroscopy (EELS) techniques were applied to cross sectional diamond film samples. We find evidence for the formation of TiC crystallites inside the TiO2 layer at different diamond growth stages. However, there is no evidence that diamond nucleation starts from these crystallites. Carbon diffusion into the TiO2 layer and the chemical bonding state of carbon (sp2/sp3) were both extensively investigated. We provide evidence that carbon diffuses through the TiO2 layer and that the diamond seeds partially convert to amorphous carbon during growth. This carbon diffusion and diamond to amorphous carbon conversion make the seed areas below the TiO2 layer grow and bend the TiO2 layer upwards to form the nucleation center of the diamond film. In some of the protuberances a core of diamond seed remains, covered by amorphous carbon. It is however unlikely that the remaining seeds are still active during the growth process.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000302887600017	Publication Date	2012-01-26
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0925-9635;	ISBN		Additional Links	UA library record; WoS full record; WoS citing articles
	Impact Factor	2.561	Times cited	16	Open Access
	Notes	Iap; Esteem 026019; Fwo			Approved	Most recent IF: 2.561; 2012 IF: 1.709
	Call Number	UA @ lucian @ c:irua:95037UA @ admin @ c:irua:95037			Serial	111
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	Author	Djotyan, A.P.; Avetisyan, A.A.; Hao, Y.L.; Peeters, F.M.
	Title	Shallow donor near a semiconductor surface in the presence of locally spherical scanning tunneling microscope tip			Type	P1 Proceeding
	Year	2012	Publication	Proceedings of the Society of Photo-optical Instrumentation Engineers T2 – Conference on Photonics and Micro and Nano-structured Materials, JUN 28-30, 2011, Yerevan, ARMENIA	Abbreviated Journal
	Volume		Issue		Pages	84140-84148
	Keywords	P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT)
	Abstract	We developed a variational approach to investigate the ground state energy and the extend of the wavefunction of a neutral donor located near a semiconductor surface in the presence of scanning tunneling microscope (STM) metallic tip. We apply the effective mass approximation and use a variational wavefunction that takes into account the influence of all image charges that arise due to the presence of a metallic tip. The behavior of the ground state energy when the tip approaches the semiconductor surface is investigated.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000303856600020	Publication Date	2012-01-20
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume	8414	Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record; WoS full record
	Impact Factor		Times cited		Open Access
	Notes	; This work was supported by the Flemish Science Foundation (FWO-Vl), and the Belgian Science Policy. One of us (AAA) was supported by a fellowship from the Belgian Federal Science Policy Office (Belspo). ;			Approved	Most recent IF: NA
	Call Number	UA @ lucian @ c:irua:113047			Serial	2987
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