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Author Tian, H.; Schryvers, D.; Mohanchandra, K.P.; Carman, G.P.; van Humbeeck, J.
Title Fabrication and characterization of functionally graded Ni-Ti multilayer thin films Type A1 Journal article
Year 2009 Publication Functional materials letters Abbreviated Journal Funct Mater Lett
Volume (down) 2 Issue 2 Pages 61-66
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A functionally graded multilayer NiTi thin film was deposited on a SiO2/Si substrate by d.c. sputtering using a ramped heated NiTi alloy target. The stand-alone films were crystallized at 500°C in vacuum better than 10-7 Torr. Transmission electron microscopy micrographs taken along the film cross section show two distinct regions, thin and thick, with weak R and B2 phases, respectively. The film compositions along the thickness were measured and quantified using the standard-less EELSMODEL method. The film deposited during the initial thermal ramp (thin regions) displays an average of 54 at.% Ni while the film deposited at a more elevated target temperature (thick regions) shows about 51 at.% Ni.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000271077000003 Publication Date 2009-07-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1793-6047;1793-7213; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.234 Times cited 9 Open Access
Notes Fwo Approved Most recent IF: 1.234; 2009 IF: 2.561
Call Number UA @ lucian @ c:irua:77655 Serial 1165
Permanent link to this record
 
 
Author Shan, L.; Punniyakoti, S.; Van Bael, M.J.; Temst, K.; Van Bael, M.K.; Ke, X.; Bals, S.; Van Tendeloo, G.; D'Olieslaeger, M.; Wagner, P.; Haenen, K.; Boyen, H.G.;
Title Homopolymers as nanocarriers for the loading of block copolymer micelles with metal salts : a facile way to large-scale ordered arrays of transition-metal nanoparticles Type A1 Journal article
Year 2014 Publication Journal of materials chemistry C : materials for optical and electronic devices Abbreviated Journal J Mater Chem C
Volume (down) 2 Issue 4 Pages 701-707
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract A new and facile approach is presented for generating quasi-regular patterns of transition metal-based nanoparticles on flat substrates exploiting polystyrene-block-poly2vinyl pyridine (PS-b-P2VP) micelles as intermediate templates. Direct loading of such micellar nanoreactors by polar transition metal salts in solution usually results in nanoparticle ensembles exhibiting only short range order accompanied by broad distributions of particle size and inter-particle distance. Here, we demonstrate that the use of P2VP homopolymers of appropriate length as molecular carriers to transport precursor salts into the micellar cores can significantly increase the degree of lateral order within the final nanoparticle arrays combined with a decrease in spreading in particle size. Thus, a significantly extended range of materials is now available which can be exploited to study fundamental properties at the transition from clusters to solids by means of well-organized, well-separated, size-selected metal and metal oxide nanostructures.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000329069900015 Publication Date 2013-11-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2050-7526;2050-7534; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.256 Times cited 5 Open Access Not_Open_Access
Notes FWO projects G.0456.12; 50 G.0346.09N; Methusalem project "NANO Approved Most recent IF: 5.256; 2014 IF: 4.696
Call Number UA @ lucian @ c:irua:113734 Serial 1489
Permanent link to this record
 
 
Author Varykhalov, A.; Marchenko, D.; Sanchez-Barriga, J.; Scholz, M.R.; Verberck, B.; Trauzettel, B.; Wehling, T.O.; Carbone, C.; Rader, O.
Title Intact dirac cones at broken sublattice symmetry : photoemission study of graphene on Ni and Co Type A1 Journal article
Year 2012 Publication Physical review X Abbreviated Journal Phys Rev X
Volume (down) 2 Issue 4 Pages 041017-10
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The appearance of massless Dirac fermions in graphene requires two equivalent carbon sublattices of trigonal shape. While the generation of an effective mass and a band gap at the Dirac point remains an unresolved problem for freestanding extended graphene, it is well established by breaking translational symmetry by confinement and by breaking sublattice symmetry by interaction with a substrate. One of the strongest sublattice-symmetry-breaking interactions with predicted and measured band gaps ranging from 400 meV to more than 3 eV has been attributed to the interfaces of graphene with Ni and Co, which are also promising spin-filter interfaces. Here, we apply angle-resolved photoemission to epitaxial graphene on Ni (111) and Co(0001) to show the presence of intact Dirac cones 2.8 eV below the Fermi level. Our results challenge the common belief that the breaking of sublattice symmetry by a substrate and the opening of the band gap at the Dirac energy are in a straightforward relation. A simple effective model of a biased bilayer structure composed of graphene and a sublattice-symmetry-broken layer, corroborated by density-functional-theory calculations, demonstrates the general validity of our conclusions.
Address
Corporate Author Thesis
Publisher Place of Publication College Park, Md Editor
Language Wos 000312703200001 Publication Date 2012-12-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2160-3308; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 12.789 Times cited 86 Open Access
Notes ; A. V. acknowledges helpful discussions with N. Sandler. This work was supported by SPP 1459 of the Deutsche Forschungsgemeinschaft. B. V. acknowledges support from the Research Foundation Flanders (FWO-Vlaanderen). B. T. and T. O. W. would like to thank the KITP at Santa Barbara for hospitality during the completion of this work. ; Approved Most recent IF: 12.789; 2012 IF: 6.711
Call Number UA @ lucian @ c:irua:105964 Serial 1677
Permanent link to this record
 
 
Author Floros, N.; Hervieu, M.; Van Tendeloo, G.; Michel, C.; Maignan, A.; Raveau, B.
Title The layered manganate Sr4-xBaxMn3O10: synthesis, structural and magnetic properties Type A1 Journal article
Year 2000 Publication Solid state sciences Abbreviated Journal Solid State Sci
Volume (down) 2 Issue 1 Pages 1-9
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000087149500001 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1293-2558; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.811 Times cited 29 Open Access
Notes Approved Most recent IF: 1.811; 2000 IF: 0.625
Call Number UA @ lucian @ c:irua:54695 Serial 1805
Permanent link to this record
 
 
Author Tikhomirov, V.K.; Vosch, T.; Fron, E.; Rodríguez, V.D.; Velázquez, J.J.; Kirilenko, D.; Van Tendeloo, G.; Hofkens, J.; Van der Auweraer, M.; Moshchalkov, V.V.
Title Luminescence of oxyfluoride glasses co-doped with Ag nanoclusters and Yb3+ ions Type A1 Journal article
Year 2012 Publication RSC advances Abbreviated Journal Rsc Adv
Volume (down) 2 Issue 4 Pages 1496-1501
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Bulk oxyfluoride glasses co-doped with Ag nanoclusters and Yb3+ ions have been prepared by a melt quenching technique. When excited in the absorption band of the Ag nanoclusters between 300 to 500 nm, these glasses emit a broad band characteristic of the Ag nanoclusters between 400 to 750 nm as well as an emission band between 900 to 1100 nm, originating from Yb3+ ions. The intensity ratio of the Yb3+/Ag emission bands increases with the Ag doping level at a fixed concentration of Yb3+, indicating the presence of energy transfer mechanism from the Ag nanoclusters to the Yb3+ ions. Comparison of time-resolved decay kinetics of the luminescence in the respectively Ag nanocluster-Yb3+ co-doped and single Ag nanocluster doped glasses, hints towards an energy transfer from the red and infrared emitting Ag nanoclusters to the Yb3+ ions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000299695300038 Publication Date 2011-12-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2046-2069; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.108 Times cited 46 Open Access
Notes Fwo; Iap Approved Most recent IF: 3.108; 2012 IF: 2.562
Call Number UA @ lucian @ c:irua:96239 Serial 1856
Permanent link to this record
 
 
Author Schryvers, D.
Title Martensitic and bainitic transformations in Ni-Al alloys Type A1 Journal article
Year 1994 Publication Journal de physique: 4 Abbreviated Journal
Volume (down) C2 Issue Pages 225-234
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Les Ulis Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1155-4339 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved
Call Number UA @ lucian @ c:irua:10014 Serial 1946
Permanent link to this record
 
 
Author Malard, B.; Pilch, J.; Sittner, P.; Gartnerova, V.; Delville, R.; Schryvers, D.; Curfs, C.
Title Microstructure and functional property changes in thin Ni-Ti wires heat teated by electric current: high energy X-ray and TEM investigations Type A1 Journal article
Year 2009 Publication Functional materials letters Abbreviated Journal Funct Mater Lett
Volume (down) 2 Issue 2 Pages 45-54
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract High energy synchrotron X-ray diffraction, transmission electron microscopy and mechanical testing were employed to investigate the evolution of microstructure, texture and functional superelastic properties of 0.1 mm thin as drawn NiTi wires subjected to a nonconventional heat treatment by controlled electric current (FTMT-EC method). As drawn NiTi wires were prestrained in tension and exposed to a sequence of short DC power pulses in the millisecond range. The annealing time in the FTMT-EC processing can be very short but the temperature and force could be very high compared to the conventional heat treatment of SMAs. It is shown that the heavily strained, partially amorphous microstructure of the as drawn NiTi wire transforms under the effect of the DC pulse and tensile stress into a wide range of annealed nanosized microstructures depending on the pulse time. The functional superelastic properties and microstructures of the FTMT-EC treated NiTi wire are comparable to those observed in straight annealed wires.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000271077000001 Publication Date 2009-07-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1793-6047;1793-7213; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.234 Times cited 21 Open Access
Notes Multimat Approved Most recent IF: 1.234; 2009 IF: 2.561
Call Number UA @ lucian @ c:irua:77656 Serial 2052
Permanent link to this record
 
 
Author Lakrimi, M.; Khym, S.; Symons, D.M.; Nicholas, R.J.; Peeters, F.M.; Mason, N.J.; Walker, P.J.
Title Mini-gaps and novel giant negative magnetoresistance in InAs/GaSb semimetallic superlattice Type A1 Journal article
Year 1998 Publication Physica. E: Low-dimensional systems and nanostructures Abbreviated Journal Physica E
Volume (down) 2 Issue Pages 363-367
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher North-Holland Place of Publication Amsterdam Editor
Language Wos 000075383500076 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1386-9477; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.221 Times cited 1 Open Access
Notes Approved Most recent IF: 2.221; 1998 IF: NA
Call Number UA @ lucian @ c:irua:24186 Serial 2083
Permanent link to this record
 
 
Author Schryvers, D.; Toth, L.; Ma, Y.; Tanner, L.E.
Title Nucleation and growth of the Ni5Al3 in NiAl austenite and martensite Type A1 Journal article
Year 1994 Publication Journal de physique: 4 Abbreviated Journal
Volume (down) C2 Issue Pages 299-304
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Les Ulis Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1155-4339 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:10015 Serial 2388
Permanent link to this record
 
 
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 (down) 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
Permanent link to this record
 
 
Author Piedigrosso, P.; Konya, Z.; Colomer, J.-F.; Fonseca, A.; Van Tendeloo, G.; Nagy, J.B.
Title Production of differently shaped multi-wall carbon nanotubes using various cobalt supported catalysts Type A1 Journal article
Year 2000 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume (down) 2 Issue 1 Pages 163-170
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Catalytic synthesis and transmission electron microscopy (TEM) of multi-wall carbon nanotubes are presented. Silica, zeolite and alumina supported cobalt catalysts were prepared by different methods (impregnation and ion-adsorption precipitation) and were used to produce nanotubes. The synthesis was carried out in a fixed bed flow reactor and the process was optimized in order to produce carbon nanotubes on a gram scale. The influence of various parameters such as the method of catalyst preparation, the nature of the support, cobalt concentration and reaction conditions on the formation of nanotubes was investigated. The carbon deposits were measured and the quality of nanotubes was determined by low and high resolution TEM. Multi-wall straight and coiled nanotubes were found to be fairly regular with an average inner (outer) diameter of 4-7 nm (8-23 nm) and with lengths up to 0.1 mm.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000084333800025 Publication Date 2002-07-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076;1463-9084; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited 53 Open Access
Notes Approved Most recent IF: 4.123; 2000 IF: 1.653
Call Number UA @ lucian @ c:irua:102889 Serial 2723
Permanent link to this record
 
 
Author Wang, Y.J.; Nichel, H.A.; McCombe, B.D.; Peeters, F.M.; Shi, J.M.; Hai, G.Q.; Wu, X.G.; Eustis, T.J.; Schaff, W.
Title Resonant magnetopolaron effect in GaAs/AlGaAs multiple quantum well structures Type A1 Journal article
Year 1998 Publication Physica. E: Low-dimensional systems and nanostructures Abbreviated Journal Physica E
Volume (down) 2 Issue Pages 161-165
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher North-Holland Place of Publication Amsterdam Editor
Language Wos 000075383500034 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1386-9477; ISBN Additional Links UA library record; WoS full record
Impact Factor 2.221 Times cited Open Access
Notes Approved Most recent IF: 2.221; 1998 IF: NA
Call Number UA @ lucian @ c:irua:24185 Serial 2888
Permanent link to this record
 
 
Author Moshnyaga, V.; Damaschke, B.; Shapoval, O.; Belenchuk, A.; Faupel, J.; Lebedev, O.I.; Verbeeck, J.; Van Tendeloo, G.; Mücksch, M.; Tsurkan, V.; Tidecks, R.; Samwer, K.
Title Structural phase transition at the percolation threshold in epitaxial (La0.7Ca0.3MnO3)1-x:(MgO)x nanocomposite films Type A1 Journal article
Year 2003 Publication Nature materials Abbreviated Journal Nat Mater
Volume (down) 2 Issue 4 Pages 247-252
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract 'Colossal magnetoresistance' in perovskite manganites such as La0.7Ca0.3MnO3 (LCMO), is caused by the interplay of ferro-paramagnetic, metal-insulator and structural phase transitions. Moreover, different electronic phases can coexist on a very fine scale resulting in percolative electron transport. Here we report on (LCMO)(1-x):(MgO)(x) (0 < x less than or equal to 0.8) epitaxial nano-composite films in which the structure and magnetotransport properties of the manganite nanoclusters can be tuned by the tensile stress originating from the MgO second phase. With increasing x, the lattice of LCMO was found to expand, yielding a bulk tensile strain. The largest colossal magnetoresistance of 10(5)% was observed at the percolation threshold in the conductivity at x(c) approximate to 0.3, which is coupled to a structural phase transition from orthorhombic (0 < x less than or equal to 0.1) to rhombohedral R (3) over barc structure (0.33 less than or equal to x less than or equal to 0.8). An increase of the Curie temperature for the R (3) over barc phase was observed. These results may provide a general method for controlling the magnetotransport properties of manganite-based composite films by appropriate choice of the second phase.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000182052700022 Publication Date 2003-03-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1476-1122;1476-4660; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 39.737 Times cited 177 Open Access
Notes Approved Most recent IF: 39.737; 2003 IF: 10.778
Call Number UA @ lucian @ c:irua:54855 Serial 3247
Permanent link to this record
 
 
Author Hadermann, J.; Van Tendeloo, G.; Abakumov, A.M.; Pavlyuk, B.P.; Rozova, M.G.; Antipov, E.V.
Title Structural transformation in fluorinated LaACuGaO5 (A=Ca, Sr) brownmillerites Type A1 Journal article
Year 2000 Publication International journal of inorganic materials Abbreviated Journal Int J Inorg Mater
Volume (down) 2 Issue 6 Pages 493-502
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000165985400005 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1466-6049; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 13 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:36043 Serial 3265
Permanent link to this record
 
 
Author Pinheiro, C.B.; Abakumov, A.M.
Title Superspace crystallography : a key to the chemistry and properties Type A1 Journal article
Year 2015 Publication IUCrJ Abbreviated Journal Iucrj
Volume (down) 2 Issue 2 Pages 137-154
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract An overview is given of the recent advances in the field of modulated molecular and inorganic crystals with an emphasis on the links between incommensurability, intermolecular and interatomic interactions and, wherever possible, the properties of the materials. The importance of detailed knowledge on the modulated structure for understanding the crystal chemistry and the functional properties of modulated phases is shown using selected examples of incommensurate modulations in organic molecular compounds and inorganic complex oxides.
Address
Corporate Author Thesis
Publisher Int union crystallography Place of Publication Chester Editor
Language Wos 000356865900016 Publication Date 2014-12-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2052-2525; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.793 Times cited 15 Open Access
Notes Approved Most recent IF: 5.793; 2015 IF: NA
Call Number c:irua:127058 Serial 3382
Permanent link to this record
 
 
Author Antipov, E.V.; Khasanova, N.R.; Pshirkov, J.S.; Putilin, S.N.; Bougerol, C.; Lebedev, O.I.; Van Tendeloo, G.; Baranov, A.N.; Park, Y.W.
Title The superconducting bismuth-based mixed oxides Type A1 Journal article
Year 2002 Publication Current applied physics T2 – QTSM and QFS 02 Symposium, MAY 08-10, 2002, SEOUL, SOUTH KOREA Abbreviated Journal Curr Appl Phys
Volume (down) 2 Issue 5 Pages 425-430
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The present paper describes the synthesis, characterization of mixed-valence bismuthates with three- or two-dimensional perovskite-like structures and structural criteria that influence superconductivity in these compounds. Single-phase samples of Sr1-xKxBiO3 were prepared for the broad range of K-content: 0.25 less than or equal to x less than or equal to 0.65. For these bismuthates the symmetry of the structure changes from monoclinic to orthorhombic and finally to tetragonal upon increasing the K-content thus resulting in the decrease of the Bi-O distances and reduction of the network distortions. Superconductivity with maximum T-c = 12 K exists in the narrow range (x approximate to 0.5-0.6) within the stability field of the tetragonal phase (0.33 less than or equal to x less than or equal to 0.65), when the three-dimensional octahedral framework has close to the ideal perovskite structure arrangement. The layered type (Ba,K)(3)Bi2O7 and (Ba,K)(2)BiO4 bismuthates belonging to the A(n+1)B(n)O(3n+1) homologous series were investigated. Buckling of the (BiO2) layers in the structure of the n = 2 member occurs due to the ordering of alkaline- and alkaline-earth cations between two independent positions. The formation of the one-layer bismuthate was revealed by Electron Microscopy and XRPD studies. Both types of compounds are considered to be possible candidates for new superconducting materials among bismuthates. (C) 2002 Published by Elsevier Science B.V.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000179330900015 Publication Date 2002-11-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1567-1739; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.971 Times cited 2 Open Access
Notes Approved Most recent IF: 1.971; 2002 IF: NA
Call Number UA @ lucian @ c:irua:103336 Serial 3598
Permanent link to this record
 
 
Author Symons, D.M.; Peeters, F.M.; Lakrimi, M.; Khym, S.; Portal, J.C.; Mason, N.J.; Nicholas, R.J.; Walker, P.J.
Title Theory of the band mixing induced negative magnetoresistance in broken gap superlattices Type A1 Journal article
Year 1998 Publication Physica. E: Low-dimensional systems and nanostructures Abbreviated Journal Physica E
Volume (down) 2 Issue Pages 353-357
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher North-Holland Place of Publication Amsterdam Editor
Language Wos 000075383500074 Publication Date 2002-07-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1386-9477; ISBN Additional Links 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; 1998 IF: NA
Call Number UA @ lucian @ c:irua:24183 Serial 3620
Permanent link to this record
 
 
Author Leusink, D.P.; Coneri, F.; Hoek, M.; Turner, S.; Idrissi, H.; Van Tendeloo, G.; Hilgenkamp, H.
Title Thin films of the spin ice compound Ho2Ti2O7 Type A1 Journal article
Year 2014 Publication APL materials Abbreviated Journal Apl Mater
Volume (down) 2 Issue 3 Pages 032101-32107
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The pyrochlore compounds Ho2Ti2O7 and Dy2Ti2O7 show an exotic form of magnetism called the spin ice state, resulting from the interplay between geometrical frustration and ferromagnetic coupling. A fascinating feature of this state is the appearance of magnetic monopoles as emergent excitations above the degenerate ground state. Over the past years, strong effort has been devoted to the investigation of these monopoles and other properties of the spin ice state in bulk crystals. Here, we report the fabrication of Ho2Ti2O7 thin films using pulsed laser deposition on yttria-stabilized ZrO2 substrates. We investigated the structural properties of these films by X-ray diffraction, scanning transmission electron microscopy, and atomic force microscopy, and the magnetic properties by vibrating sample magnetometry at 2 K. The films not only show a high crystalline quality, but also exhibit the hallmarks of a spin ice: a pronounced magnetic anisotropy and an intermediate plateau in the magnetization along the [111] crystal direction.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000334220300002 Publication Date 2014-03-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2166-532X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.335 Times cited 18 Open Access
Notes The authors acknowledge support from the Dutch FOM and NWO foundations and from the European Union under the Framework 7 program under a contract from an Integrated Infrastructure Initiative (Reference 312483 ESTEEM2). G.V.T. acknowledges the ERC Grant N246791- COUNTATOMS. S.T. gratefully acknowledges financial support from the Fund for Scientific Research Flanders (FWO). H.I. acknowledges the IAP program of the Belgian State Federal Office for Scientific, Technical and Cultural Affairs under Contract No. P7/21. The microscope used in this study was partially financed by the Hercules Foundation of the Flemish Government. The authors acknowledge fruitful interactions with A. Brinkman, M. G. Blamire, M. Egilmez, F. J. G. Roesthuis, J. N. Beukers, C. G. Molenaar, M. Veldhorst, and X. Renshaw Wang; esteem2_ta Approved Most recent IF: 4.335; 2014 IF: NA
Call Number UA @ lucian @ c:irua:115555 Serial 3641
Permanent link to this record
 
 
Author Hamon, C.; Novikov, S.M.; Scarabelli, L.; Solís, D.M.; Altantzis, T.; Bals, S.; Taboada, J.M.; Obelleiro, F.; Liz-Marzán, L.M.
Title Collective Plasmonic Properties in Few-Layer Gold Nanorod Supercrystals Type A1 Journal article
Year 2015 Publication ACS Photonics Abbreviated Journal Acs Photonics
Volume (down) 2 Issue 2 Pages 1482-1488
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Gold nanorod supercrystals have been widely employed for the detection of relevant bioanalytes with detection limits ranging from nano- to picomolar levels,

confirming the promising nature of these structures for biosensing. Even though a relationship between the height of the supercrystal (i.e., the number of stacked nanorod layers)and the enhancement factor has been proposed, no systematic

study has been reported. In order to tackle this problem, we prepared gold nanorod supercrystals with varying numbers of stacked layers and analyzed them extensively by atomic force microscopy, electron microscopy and surface enhanced Raman scattering. The experimental results were compared to numerical

simulations performed on real-size supercrystals composed of thousands of nanorod building blocks. Analysis of the hot spot distribution in the simulated supercrystals showed the presence of standing waves that were distributed at different depths, depending on the number of layers in each supercrystal. On the basis of these theoretical results, we interpreted the experimental

data in terms of analyte penetration into the topmost layer only, which indicates that diffusion to the interior of the supercrystals would be crucial if the complete field enhancement produced by the stacked nanorods is to be exploited. We propose that our conclusions will be of high relevance in the design of next generation plasmonic devices.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000363435600013 Publication Date 2015-09-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2330-4022 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.756 Times cited 70 Open Access OpenAccess
Notes The authors are thankful to Dr. Luis Yate for assistance with sample preparation. This work was supported by the European Research Council (ERC Advanced Grant #267867 Plasmaquo and ERC Starting Grant #335078 Colouratom) and the Spanish Ministerio de Economía y Competitividad (MAT2013-46101-R). D.M.S., J.M.T., and F.O. acknowledge funding from the European Regional Development Fund (ERDF) and the Spanish Ministerio de Economiá y Competitividad (MAT2014-58201-C2-1-R, MAT2014-58201- C2-2-R, Project TACTICA), from the ERDF and the Galician Regional Government under Projects CN2012/279 and CN2012/260 (AtlantTIC) and the Plan I2C (2011−2015), and from the ERDF and the Extremadura Regional Government (Junta de Extremadura Project IB13185).; ECAS_Sara; (ROMEO:white; preprint:; postprint:restricted 12 months embargo; pdfversion:cannot); Approved Most recent IF: 6.756; 2015 IF: NA
Call Number c:irua:129458 Serial 3978
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Author Yao, X.; Cao, S.; Zhang, X.P.; Schryvers, D.
Title Microstructural Characterization and Transformation Behavior of Porous Ni50.8Ti49.2 Type P1 Proceeding
Year 2015 Publication Materials Today: Proceedings Abbreviated Journal
Volume (down) 2 Issue 2 Pages S833-S836
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract Porous Ni50.8Ti49.2 bulk material was prepared by powder metallurgy sintering. Solid solution and aging treatments were applied to improve the phase homogeneity and phase transformation behavior. Scanning and transmission electron microscopy, aided by energy dispersive X-ray analysis, were used to study the microstructure and chemical phase content of the alloys. In-situ cooling was carried out to observe the phase transformation behavior. As-received material contains dispersed Ni2Ti4O particles while Ni4Ti3 precipitates appear after aging. Close to pore edges, the latter have a preferential orientation due to the induced stress fields in the matrix.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000371032100081 Publication Date 2015-11-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2214-7853 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes The author gratefully acknowledges the Chinese Scholarship Council (CSC) for providing a scholarship and the Key Project of the Natural Science Foundation of Guangdong Province under grant No. S2013020012805. Approved Most recent IF: NA
Call Number c:irua:129980 Serial 3989
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Author Ozaydin, H.D.; Sahin, H.; Kang, J.; Peeters, F.M.; Senger, R.T.
Title Electronic and magnetic properties of 1T-TiSe2 nanoribbons Type A1 Journal article
Year 2015 Publication 2D materials Abbreviated Journal 2D Mater
Volume (down) 2 Issue 2 Pages 044002
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Motivated by the recent synthesis of single layer TiSe2, we used state-of-the-art density functional theory calculations, to investigate the structural and electronic properties of zigzag and armchair-edged nanoribbons (NRs) of this material. Our analysis reveals that, differing from ribbons of other ultra-thin materials such as graphene, TiSe2 NRs have some distinctive properties. The electronic band gap of the NRs decreases exponentially with the width and vanishes for ribbons wider than 20 angstrom. For ultranarrow zigzag-edged NRs we find odd-even oscillations in the band gap width, although their band structures show similar features. Moreover, our detailed magnetic-ground-state analysis reveals that zigzag and armchair edged ribbons have non-magnetic ground states. Passivating the dangling bonds with hydrogen at the edges of the structures influences the band dispersion. Our results shed light on the characteristic properties of T phase NRs of similar crystal structures.
Address
Corporate Author Thesis
Publisher IOP Publishing Place of Publication Bristol Editor
Language Wos 000368936600005 Publication Date 2015-10-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2053-1583 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.937 Times cited 20 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAK-BIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus Short Marie Curie Fellowship. HDO, HS and RTS acknowledge the support from TUBITAK through project 114F397. ; Approved Most recent IF: 6.937; 2015 IF: NA
Call Number UA @ lucian @ c:irua:131602 Serial 4169
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Author Idrissi, H.; Bollinger, C.; Boioli, F.; Schryvers, D.; Cordier, P.
Title Low-temperature plasticity of olivine revisited with in situ TEM nanomechanical testing Type A1 Journal article
Year 2016 Publication Science Advances Abbreviated Journal
Volume (down) 2 Issue 2 Pages e1501671-e1501671
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The rheology of the lithospheric mantle is fundamental to understanding how mantle convection couples with plate tectonics. However, olivine rheology at lithospheric conditions is still poorly understood because experiments are difficult in this temperature range where rocks and mineral become very brittle. We combine techniques of quantitative in situ tensile testing in a transmission electron microscope and numerical modeling of dislocation dynamics to constrain the low-temperature rheology of olivine. We find that the intrinsic ductility of olivine at low temperature is significantly lower than previously reported values, which were obtained under strain-hardened conditions. Using this method, we can anchor rheological laws determined at higher temperature and can provide a better constraint on intermediate temperatures relevant for the lithosphere. More generally, we demonstrate the possibility of characterizing the mechanical properties of specimens, which can be available in the form of submillimeter-sized particles only.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000379620200043 Publication Date 2016-03-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2375-2548 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 32 Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:134983 Serial 4202
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Author Venturi, F.; Calizzi, M.; Bals, S.; Perkisas, T.; Pasquini, L.
Title Self-assembly of gas-phase synthesized magnesium nanoparticles on room temperature substrates Type A1 Journal article
Year 2015 Publication Materials research express Abbreviated Journal Mater Res Express
Volume (down) 2 Issue 2 Pages 015007
Keywords A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT)
Abstract Magnesium nanoparticles (NPs) with initial size in the 10-50 nmrange were synthesized by inert gas condensation under helium flow and deposited on room temperature substrates. The morphology and crystal structure of the NPs ensemble were investigated as a function of the deposition time by complementary electron microscopy techniques, including high resolution imaging and chemical mapping. With increasing amount of material, strong coarsening phenomena were observed at room temperature: small NPs disappeared while large faceted NPs developed, leading to a 5-fold increase of the average NPs size within a few minutes. The extent of coarsening and the final morphology depended also on the nature of the substrate. Furthermore, large single-crystal NPs were seen to arise from the self-organization of primary NPs units, providing a mechanism for crystal growth. The dynamics of the self-assembly process involves the basic steps of NPs sticking, diffusion on substrate, coordinated rotation and attachment/coalescence. Key features are the surface energy anisotropy, reflected by the faceted shape of the NPs, and the low melting point of the material. The observed phenomena have strong implications in relation to the synthesis and stability of nanostructures based on Mg or other elements with similar features.
Address
Corporate Author Thesis
Publisher IOP Publishing Place of Publication Bristol Editor
Language Wos 000369978500007 Publication Date 2014-12-31
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2053-1591 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.068 Times cited 14 Open Access Not_Open_Access
Notes ; Financial support by COST Action MP1103 'Nanostructured Materials for Solid-State Hydrogen Storage' is gratefully acknowledged. ; Approved Most recent IF: 1.068; 2015 IF: NA
Call Number UA @ lucian @ c:irua:132275 Serial 4240
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Author Yao, X.; Amin-Ahmadi, B.; Li, Y.; Cao, S.; Ma, X.; Zhang, X.-P.; Schryvers, D.
Title Optimization of Automated Crystal Orientation Mapping in a TEM for Ni4Ti3 Precipitation in All-Round SMA Type A1 Journal article
Year 2016 Publication Shape memory and superelasticity Abbreviated Journal Shap Mem Superelasticity
Volume (down) 2 Issue 2 Pages 286-297
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Automated crystal orientation and phase mapping in TEM are applied to the quantification of Ni4Ti3 precipitates in Ni–Ti shape memory alloys which will be used for the implantation of artificial sphincters operating using the all-round shape memory effect. This paper focuses on the optimization process of the technique to obtain best values for all major parameters in the acquisition of electron diffraction patterns as well as template generation. With the obtained settings, vast statistical data on nano- and microstructures essential to the operation of these shape memory devices become available.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000408743700001 Publication Date 2016-11-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2199-384X ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 2 Open Access
Notes X. Yao gratefully acknowledges the Chinese Scholarship Council (CSC) for providing a PhD scholarship. Research support was also provided by the Key Project of the Natural Science Foundation of Guangdong Province (S2013020012805) and the Natural Science Foundation of China under Grant No. 51401081. Approved Most recent IF: NA
Call Number EMAT @ emat @ c:irua:138600 Serial 4324
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Author Zhang, B.; Deschamps, M.; Ammar, M.-R.; Raymundo-Pinero, E.; Hennet, L.; Batuk, D.; Tarascon, J.-M.
Title Laser synthesis of hard carbon for anodes in Na-ion battery Type A1 Journal article
Year 2017 Publication Advanced Materials Technologies Abbreviated Journal
Volume (down) 2 Issue 3 Pages 1600227
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000398999900003 Publication Date 2016-12-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2365-709x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 10 Open Access Not_Open_Access
Notes ; The RS2E (Reseau sur le StockageElectrochimique de l'Energie) network is acknowledged for the financial support of this work through the ANR project Storex (ANR-10-LABX-76-01). J.-M.T acknowledges funding from the European Research Council (ERC) (FP/2014-2020)/ERC GrantProject 670116-ARPEMA. ; Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:142452 Serial 4666
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Author De Clercq, M.; Moors, K.; Sankaran, K.; Pourtois, G.; Dutta, S.; Adelmann, C.; Magnus, W.; Sorée, B.
Title Resistivity scaling model for metals with conduction band anisotropy Type A1 Journal article
Year 2018 Publication Physical review materials Abbreviated Journal
Volume (down) 2 Issue 3 Pages 033801
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract It is generally understood that the resistivity of metal thin films scales with film thickness mainly due to grain boundary and boundary surface scattering. Recently, several experiments and ab initio simulations have demonstrated the impact of crystal orientation on resistivity scaling. The crystal orientation cannot be captured by the commonly used resistivity scaling models and a qualitative understanding of its impact is currently lacking. In this work, we derive a resistivity scaling model that captures grain boundary and boundary surface scattering as well as the anisotropy of the band structure. The model is applied to Cu and Ru thin films, whose conduction bands are (quasi-) isotropic and anisotropic, respectively. After calibrating the anisotropy with ab initio simulations, the resistivity scaling models are compared to experimental resistivity data and a renormalization of the fitted grain boundary reflection coefficient can be identified for textured Ru.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication College Park, Md Editor
Language Wos 000426787600001 Publication Date 2018-03-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes ; The authors acknowledge the support by the Fonds National de la Recherche Luxembourg (ATTRACT Grant No. 7556175). ; Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:149866UA @ admin @ c:irua:149866 Serial 4947
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Author Perez, A.J.; Jacquet, Q.; Batuk, D.; Iadecola, A.; Saubanere, M.; Rousse, G.; Larcher, D.; Vezin, H.; Doublet, M.-L.; Tarascon, J.-M.
Title Approaching the limits of cationic and anionic electrochemical activity with the Li-rich layered rocksalt Li3IrO4 Type A1 Journal article
Year 2017 Publication Nature energy Abbreviated Journal Nat Energy
Volume (down) 2 Issue 12 Pages 954-962
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract The Li-rich rocksalt oxides Li2MO3 (M = 3d/4d/5d transition metal) are promising positive-electrode materials for Li-ion batteries, displaying capacities exceeding 300 mAh g(-1) thanks to the participation of the oxygen non-bonding O(2p) orbitals in the redox process. Understanding the oxygen redox limitations and the role of the O/M ratio is therefore crucial for the rational design of materials with improved electrochemical performances. Here we push oxygen redox to its limits with the discovery of a Li3IrO4 compound (O/M = 4) that can reversibly take up and release 3.5 electrons per Ir and possesses the highest capacity ever reported for any positive insertion electrode. By quantitatively monitoring the oxidation process, we demonstrate the material's instability against O-2 release on removal of all Li. Our results show that the O/M parameter delineates the boundary between the material's maximum capacity and its stability, hence providing valuable insights for further development of high-capacity materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000430218300001 Publication Date 2017-12-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2058-7546 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 55 Open Access Not_Open_Access
Notes ; We thank P. Pearce for providing the beta-Li<INF>2</INF>IrO<INF>3</INF> and L. Lemarquis for helping in the DEMS experiment. We are particularly grateful to S. Belin, V. Briois and L. Stievano for helpful discussions on XAS analysis and synchrotron SOLEIL (France) for providing beamtime at the ROCK beamline (financed by the French National Research Agency (ANR) as part of the 'Investissements d'Avenir' programme, reference: ANR-10-EQPX-45). A.J.P and A. I. acknowledge the GdR C(RS) 2 for the workshop organized on a chemometric approach for XAS data analysis. V. Nassif is acknowledged for her help during neutron diffraction experiments performed at Institut Laue Langevin on D1B. Use of the 11-BM mail service of the APS at Argonne National Laboratory was supported by the US Department of Energy under contract No. DE-AC02-06CH11357 and is gratefully acknowledged. This work has been performed with the support of the European Research Council (ERC) (FP/2014)/ERC Grant- Project 670116 ARPEMA. ; Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:150926 Serial 4962
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Author Andelkovic, M.; Covaci, L.; Peeters, F.M.
Title DC conductivity of twisted bilayer graphene: Angle-dependent transport properties and effects of disorder Type A1 Journal article
Year 2018 Publication Physical review materials Abbreviated Journal
Volume (down) 2 Issue 3 Pages 034004
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The in-plane dc conductivity of twisted bilayer graphene is calculated using an expansion of the real-space Kubo-Bastin conductivity in terms of Chebyshev polynomials. We investigate within a tight-binding approach the transport properties as a function of rotation angle, applied perpendicular electric field, and vacancy disorder. We find that for high-angle twists, the two layers are effectively decoupled, and the minimum conductivity at the Dirac point corresponds to double the value observed in monolayer graphene. This remains valid even in the presence of vacancies, hinting that chiral symmetry is still preserved. On the contrary, for low twist angles, the conductivity at the Dirac point depends on the twist angle and is not protected in the presence of disorder. Furthermore, for low angles and in the presence of an applied electric field, we find that the chiral boundary states emerging between AB and BA regions contribute to the dc conductivity, despite the appearance of localized states in the AA regions. The results agree qualitatively with recent transport experiments in low-angle twisted bilayer graphene.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication College Park, Md Editor
Language Wos 000427822700002 Publication Date 2018-03-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 27 Open Access
Notes ; We acknowledge financial support from the graphene FLAG-ERA project TRANS2DTMD. ; Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:150838UA @ admin @ c:irua:150838 Serial 4964
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Author Zhang, H.; Gauquelin, N.; McMahon, C.; Hawthorn, D.G.; Botton, G.A.; Wei, J.Y.T.
Title Synthesis of high-oxidation Y-Ba-Cu-O phases in superoxygenated thin films Type A1 Journal article
Year 2018 Publication Physical review materials Abbreviated Journal
Volume (down) 2 Issue 3 Pages 033803
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract It is known that solid-state reaction in high-pressure oxygen can stabilize high-oxidation phases of Y-Ba-Cu-O superconductors in powder form. We extend this superoxygenation concept of synthesis to thin films which, due to their large surface-to-volume ratio, are more reactive thermodynamically. Epitaxial thin films of YBa2Cu3O7-delta grown by pulsed laser deposition are annealed at up to 700 atm O-2 and 900 degrees C, in conjunction with Cu enrichment by solid-state diffusion. The films show the clear formation of Y2Ba4Cu7O15-delta and Y2Ba4Cu8O16 as well as regions of YBa2Cu5O9-delta and YBa2Cu6O10-delta phases, according to scanning transmission electron microscopy, x-ray diffraction, and x-ray absorption spectroscopy. Similarly annealed YBa2Cu3O7-delta powders show no phase conversion. Our results demonstrate a route of synthesis towards discovering more complex phases of cuprates and other superconducting oxides.
Address
Corporate Author Thesis
Publisher American Physical Society Place of Publication College Park, Md Editor
Language Wos 000428244900004 Publication Date 2018-03-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 2 Open Access Not_Open_Access
Notes ; This work is supported by NSERC, CFI-OIT, and CIFAR. The electron microscopy work was carried out at the Canadian Centre for Electron Microscopy, a National Facility supported by the Canada Foundation for Innovation under the Major Science Initiative program, McMaster University, and NSERC. The XAS work was performed at the Canadian Light Source, which is supported by NSERC, NRC, CIHR, and the University of Saskatchewan. ; Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:150829 Serial 4982
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Author Hai, G.-Q.; Candido, L.; Brito, B.G.A.; Peeters, F.M.
Title Electron pairing: from metastable electron pair to bipolaron Type A1 Journal article
Year 2018 Publication Journal of physics communications Abbreviated Journal
Volume (down) 2 Issue 3 Pages Unsp 035017
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Starting from the shell structure in atoms and the significant correlation within electron pairs, we distinguish the exchange-correlation effects between two electrons of opposite spins occupying the same orbital from the average correlation among many electrons in a crystal. In the periodic potential of the crystal with lattice constant larger than the effective Bohr radius of the valence electrons, these correlated electron pairs can form a metastable energy band above the corresponding single-electron band separated by an energy gap. In order to determine if these metastable electron pairs can be stabilized, we calculate the many-electron exchange-correlation renormalization and the polaron correction to the two-band system with single electrons and electron pairs. We find that the electron-phonon interaction is essential to counterbalance the Coulomb repulsion and to stabilize the electron pairs. The interplay of the electron-electron and electron-phonon interactions, manifested in the exchange-correlation energies, polaron effects, and screening, is responsible for the formation of electron pairs (bipolarons) that are located on the Fermi surface of the single-electron band.
Address
Corporate Author Thesis
Publisher IOP Publishing Place of Publication Bristol Editor
Language Wos 000434996900022 Publication Date 2018-02-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2399-6528 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 9 Open Access
Notes ; This work was supported by the Brazilian agencies FAPESP and CNPq. GQH would like to thank Prof. Bangfen Zhu for his invaluable support and expert advice. ; Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:152079UA @ admin @ c:irua:152079 Serial 5022
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