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Author Brammertz, G.; Buffiere, M.; Verbist, C.; Bekaert, J.; Batuk, M.; Hadermann, J.; et al.
Title Process variability in Cu2ZnSnSe4 solar cell devices: Electrical and structural investigations Type P1 Proceeding
Year 2015 Publication The conference record of the IEEE Photovoltaic Specialists Conference T2 – IEEE 42nd Photovoltaic Specialist Conference (PVSC), JUN 14-19, 2015, New Orleans, LA Abbreviated Journal
Volume Issue Pages
Keywords P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract We have fabricated 9.7% efficient Cu2ZnSnSe4/CdS/ZnO solar cells by H2Se selenization of sequentially sputtered metal layers. Despite the good efficiency obtained, process control appears to be difficult. In the present contribution we compare the electrical and physical properties of two devices with nominal same fabrication procedure, but 1% and 9.7% power conversion efficiency respectively. We identify the problem of the lower performing device to be the segregation of ZnSe phases at the backside of the sample. This ZnSe seems to be the reason for the strong bias dependent photocurrent observed in the lower performing devices, as it adds a potential barrier for carrier collection. The reason for the different behavior of the two nominally same devices is not fully understood, but speculated to be related to sputtering variability.
Address
Corporate Author Thesis
Publisher Ieee Place of Publication New york Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 978-1-4799-7944-8 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:132335 Serial 4229
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Author Charkin, D.O.; Akinfiev, V.S.; Alekseeva, A.M.; Batuk, M.; Abakumov, A.M.; Kazakov, S.M.
Title Synthesis and cation distribution in the new bismuth oxyhalides with the Sillen-Aurivillius intergrowth structures Type A1 Journal article
Year 2015 Publication Journal of the Chemical Society : Dalton transactions Abbreviated Journal Dalton T
Volume 44 Issue 44 Pages 20568-20576
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract About 20 new compounds with the Sillen-Aurivillius intergrowth structure, (MeMeBi3Nb2O11X)-Me-1-Bi-2 (Me-1 = Pb, Sr, Ba; Me-2 = Ca, Sr, Ba; X = Cl, Br, I), have been prepared. They are composed of stacking of [ANb(2)O(7)] perovskite blocks, fluorite-type [M2O2] blocks and halogen sheets. The cation distribution between the fluorite and perovskite layers has been studied for Ba2Bi3Nb2O11I, Ca1.25Sr0.75Bi3Nb2O11Cl, BaCaBi3Nb2O11Br and Sr2Bi3Nb2O11Cl. The smaller Me cations tend to reside in the perovskite block while the larger ones are situated in the fluorite-type block. The distribution of the elements was confirmed for BaCaBi3Nb2O11Br using energy dispersive X-ray analysis combined with scanning transmission electron microscopy (STEM-EDX). An electron diffraction study of this compound reveals a local symmetry lowering caused by weakly correlated rotation of NbO6 octahedra. Based on our findings, we suggest a new stability criterion for mixed-layer structures, which is that net charges of any two consecutive layers do not compensate for each other and only the whole layer sequence is electroneutral.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000365411500036 Publication Date 2015-10-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0300-9246; 1477-9226; 1472-7773 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.029 Times cited 5 Open Access
Notes Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:130330 Serial 4256
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Author Rozova, M.G.; Grigoriev, V.V.; Bobrikov, I.A.; Filimonov, D.S.; Zakharov, K.V.; Volkova, O.S.; Vasiliev, A.N.; Antipov, E.V.; Tsirlin, A.A.; Abakumov, A.M.
Title Synthesis, structure and magnetic ordering of the mullite-type Bi2Fe4-xCrxO9 solid solutions with a frustrated pentagonal Cairo lattice Type A1 Journal article
Year 2016 Publication Journal of the Chemical Society : Dalton transactions Abbreviated Journal Dalton T
Volume 45 Issue 45 Pages 1192-1200
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Highly homogeneous mullite-type solid solutions Bi2Fe4-xCrxO9 (x = 0.5, 1, 1.2) were synthesized using a soft chemistry technique followed by a solid-state reaction in Ar. The crystal structure of Bi2Fe3CrO9 was investigated using X-ray and neutron powder diffraction, transmission electron microscopy and Fe-57 Mossbauer spectroscopy (S.G. Pbam, a = 7.95579(9) angstrom , b = 8.39145(9) angstrom, c = 5.98242(7) angstrom, R-F(X-ray) = 0.022, R-F(neutron) = 0.057). The ab planes in the structure are tessellated with distorted pentagonal loops built up by three tetrahedrally coordinated Fe sites and two octahedrally coordinated Fe/Cr sites, linked together in the ab plane by corner-sharing forming a pentagonal Cairo lattice. Magnetic susceptibility measurements and powder neutron diffraction show that the compounds order antiferromagnetically (AFM) with the Neel temperatures decreasing upon increasing the Cr content from T-N similar to 250 K for x = 0 to T-N similar to 155 K for x = 1.2. The magnetic structure of Bi2Fe3CrO9 at T = 30 K is characterized by a propagation vector k = (1/2,1/2,1/2). The tetrahedrally coordinated Fe cations form singlet pairs within dimers of corner-sharing tetrahedra, but spins on the neighboring dimers are nearly orthogonal. The octahedrally coordinated (Fe, Cr) cations form antiferromagnetic up-up-down-down chains along c, while the spin arrangement in the ab plane is nearly orthogonal between nearest neighbors and collinear between second neighbors. The resulting magnetic structure is remarkably different from the one in pure Bi2Fe4O9 and features several types of spin correlations even on crystallographically equivalent exchange that may be caused by the simultaneous presence of Fe and Cr on the octahedral site.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000367614700041 Publication Date 2015-11-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0300-9246; 1477-9226; 1472-7773 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.029 Times cited Open Access
Notes Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:131095 Serial 4257
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Author Sieger, M.; Pahlke, P.; Ottolinger, R.; Stafford, B.H.; Lao, M.; Meledin, A.; Bauer, M.; Eisterer, M.; Van Tendeloo, G.; Schultz, L.; Nielsch, K.; Hühne, R.
Title Influence of substrate tilt angle on the incorporation of BaHfO3 in thick YBa2Cu3O7-δ films Type A1 Journal article
Year 2016 Publication IEEE transactions on applied superconductivity Abbreviated Journal
Volume 27 Issue 27 Pages 1-4
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract High critical current densities can be realized in high-temperature superconductors such as YBa2Cu3O7-δ (YBCO) by controlling density, shape, size and direction of a secondary phase. Whereas the dependence on the growth rate and deposition temperature has been widely studied as key parameters for nano-engineering the pinning landscape, the vicinal tilt of the substrate surface might have an additional influence. Therefore, we deposited 6 mol% BaHfO3 (BHO) doped YBCO on SrTiO3 (STO) substrates with vicinal angles α between 0° and 40° to identify the influence of the tilt on the growth mode of BHO. An undisturbed epitaxial growth of the superconductor as well as an epitaxial integration of the BHO phase in the YBCO matrix is observed for all vicinal angles investigated. The critical temperature is constant up to α = 20°, whereas the self-field critical current density at 77 K starts to decrease above 10°. A detailed structural analysis of the film cross sections showed that the growth mode of BHO changes already for a vicinal tilt of 2° from a pure c-axis oriented growth to a layered structure with BHO aligned parallel to the YBCO ab-plane. We identified a strong influence of such a microstructure on the current flow in BHO doped YBCO films on STO substrates as well as on MgO based coated conductors prepared by inclined substrate deposition
Address
Corporate Author Thesis
Publisher Institute of Electrical and Electronics Engineers (IEEE) Place of Publication Editor
Language Wos 000418469400001 Publication Date 2016-11-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1051-8223 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 3 Open Access
Notes This work was supported by EUROTAPES, a collaborative project funded by the European Commission’s Seventh Framework Program (FP7 / 2007 – 2013) under Grant Agreement n.280432.The authors would like to thank R. Nast, M. Reitner, M. Kühnel, U. Fiedler and J. Scheiter for technical assistance. Approved (down) Most recent IF: NA
Call Number EMAT @ emat @ Sieger_2016a c:irua:138603 Serial 4317
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Author Moldovan, D.; Peeters, F.M.
Title Atomic Collapse in Graphene Type P1 Proceeding
Year 2016 Publication Nanomaterials For Security Abbreviated Journal
Volume Issue Pages 3-17
Keywords P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract When the charge Z of an atom exceeds the critical value of 170, it will undergo a process called atomic collapse which triggers the spontaneous creation of electron-positron pairs. The high charge requirements have prevented the observation of this phenomenon with real atomic nuclei. However, thanks to the relativistic nature of the carriers in graphene, the same physics is accessible at a much lower scale. The atomic collapse analogue in graphene is realized using artificial nuclei which can be created via the deposition of impurities on the surface of graphene or using charged vacancies. These supercritically charged artificial nuclei trap electrons in a sequence of quasi-bound states which can be observed experimentally as resonances in the local density of states.
Address
Corporate Author Thesis
Publisher Springer Place of Publication Dordrecht Editor
Language Wos 000386506200001 Publication Date 2016-07-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 978-94-017-7593-9; 978-94-017-7591-5 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 3 Open Access
Notes ; ; Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:138237 Serial 4348
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Author Sobrino Fernández, M.
Title Confinement induced assembly of anisotropic particles : patchy colloids and water molecules Type Doctoral thesis
Year 2016 Publication Abbreviated Journal
Volume Issue Pages
Keywords Doctoral thesis; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Antwerpen Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:135841 Serial 4349
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Author Van de Put, M.L.
Title Modeling of quantum electron transport with applications in energy filtering nanostructures Type Doctoral thesis
Year 2016 Publication Abbreviated Journal
Volume Issue Pages
Keywords Doctoral thesis; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Antwerpen Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:138752 Serial 4357
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Author Eijt, S.W.H.; Shi, W.; Mannheim, A.; Butterling, M.; Schut, H.; Egger, W.; Dickmann, M.; Hugenschmidt, C.; Shakeri, B.; Meulenberg, R.W.; Callewaert, V.; Saniz, R.; Partoens, B.; Barbiellini, B.; Bansil, A.; Melskens, J.; Zeman, M.; Smets, A.H.M.; Kulbak, M.; Hodes, G.; Cahen, D.; Brück, E.
Title New insights into the nanostructure of innovative thin film solar cells gained by positron annihilation spectroscopy Type A1 Journal article
Year 2017 Publication Journal of physics : conference series Abbreviated Journal
Volume 791 Issue 791 Pages 012021
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Recent studies showed that positron annihilation methods can provide key insights into the nanostructure and electronic structure of thin film solar cells. In this study, positron annihilation lifetime spectroscopy (PALS) is applied to investigate CdSe quantum dot (QD) light absorbing layers, providing evidence of positron trapping at the surfaces of the QDs. This enables one to monitor their surface composition and electronic structure. Further, 2D-Angular Correlation of Annihilation Radiation (2D-ACAR) is used to investigate the nanostructure of divacancies in photovoltaic-high-quality a-Si:H films. The collected momentum distributions were converted by Fourier transformation to the direct space representation of the electron-positron autocorrelation function. The evolution of the size of the divacancies as a function of hydrogen dilution during deposition of a-Si:H thin films was examined. Finally, we present a first positron Doppler Broadening of Annihilation Radiation (DBAR) study of the emerging class of highly efficient thin film solar cells based on perovskites.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000400610500021 Publication Date 2017-02-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1742-6588 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 1 Open Access
Notes The work at Delft University of Technology was supported by the China Scholarship Council (CSC) grant of W.S., by ADEM, A green Deal in Energy Materials of the Ministry of Economic Affairs of The Netherlands (www.adem- innovationlab.nl), and the STW Vidi grant of A.S., Grant No. 10782. The PALS study is based upon experiments performed at the PLEPS instrument of the NEPOMUC facility at the Heinz Maier-Leibnitz Zentrum (MLZ), Garching, Germany, and was supported by the European Commission under the 7 th Framework Programme, Key Action: Strengthening the European Research Area, Research Infrastructures, Contract No. 226507, NMI3. The work at University of Maine was supported by the National Science Foundation under Grant No. DMR-1206940. Research at the University of Antwerp was supported by FWO grants G022414N and G015013. The work at Northeastern University was supported by the US Department of Energy (DOE), Office of Science, Basic Energy Sciences grant number DE-FG02-07ER46352 (core research), and benefited from Northeastern University's Advanced Scientific Computation Center (ASCC), the NERSC supercomputing center through DOE grant number DE-AC02-05CH11231, and support (applications to layered materials) from the DOE EFRC: Center for the Computational Design of Functional Layered Materials (CCDM) under DE-SC0012575. The work at the Weizmann Institute was supported by the Sidney E. Frank Foundation through the Israel Science Foundation, by the Israel Ministry of Science, and the Israel National Nano-Initiative. D.C. holds the Sylvia and Rowland Schaefer Chair in Energy Research. Approved (down) Most recent IF: NA
Call Number CMT @ cmt @ c:irua:140850 Serial 4426
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Author Grzelczak, M.; Sanchez-Iglesias, A.; Heidari, H.; Bals, S.; Pastoriza-Santos, I.; Perez-Juste, J.; Liz-Marzan, L.M.
Title Silver Ions Direct Twin-Plane Formation during the Overgrowth of Single-Crystal Gold Nanoparticles Type A1 Journal article
Year 2016 Publication ACS Omega Abbreviated Journal
Volume 1 Issue 1 Pages 177-181
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract It is commonly agreed that the crystalline structure of seeds dictates the crystallinity of final nanoparticles in a seeded-growth process. Although the formation of monocrystalline particles does require the use of single-crystal seeds, twin planes may stem from either single-or polycrystalline seeds. However, experimental control over twin-plane formation remains difficult to achieve synthetically. Here, we show that a careful interplay between kinetics and selective surface passivation offers a unique handle over the emergence of twin planes (in decahedra and triangles) during the growth over single-crystalline gold nanoparticles of quasi-spherical shape. Twinning can be suppressed under conditions of slow kinetics in the presence of silver ions, yielding single-crystalline particles with high-index facets.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000391203300002 Publication Date 2016-08-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-1343;2470-1343; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 18 Open Access OpenAccess
Notes ; This work was supported by the Spanish Ministerio de Economia y Competitividad MINECO (grants: MAT2013-46101-R, MAT2013-49375-EXP, MAT2013-45168-R). Financial support is acknowledged by the European Research Council (ERC Advanced Grant # 267867, PLASMAQUO; ERC Starting Grant #335078-COLOURATOM). ; ecas_Sara Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:140398 Serial 4446
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Author Neilson, D.; Perali, A.; Zarenia, M.
Title Many-body electron correlations in graphene Type P1 Proceeding
Year 2016 Publication (mbt18) Abbreviated Journal
Volume 702 Issue 702 Pages 012008
Keywords P1 Proceeding; Condensed Matter Theory (CMT)
Abstract The conduction electrons in graphene promise new opportunities to access the region of strong many-body electron-electron correlations. Extremely high quality, atomically flat two-dimensional electron sheets and quasi-one-dimensional electron nanoribbons with tuneable band gaps that can be switched on by gates, should exhibit new many-body phenomena that have long been predicted for the regions of phase space where the average Coulomb repulsions between electrons dominate over their Fermi energies. In electron nanoribbons a few nanometres wide etched in monolayers of graphene, the quantum size effects and the van Hove singularities in their density of states further act to enhance electron correlations. For graphene multilayers or nanoribbons in a double unit electron-hole geometry, it is possible for the many-body electron-hole correlations to be made strong enough to stabilise high-temperature electron- hole superfluidity.
Address
Corporate Author Thesis
Publisher Iop publishing ltd Place of Publication Bristol Editor
Language Wos 000389756000008 Publication Date 2016-04-29
Series Editor Series Title Abbreviated Series Title
Series Volume 702 Series Issue Edition
ISSN 1742-6588; 1742-6596 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 3 Open Access
Notes ; ; Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:140268 Serial 4455
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Author Bogaerts, A.; Snoeckx, R.; Berthelot, A.; Heijkers, S.; Wang, W.; Sun, S.; Van Laer, K.; Ramakers, M.; Michielsen, I.; Uytdenhouwen, Y.; Meynen, V.; Cool, P.
Title Plasma based co2 conversion: a combined modeling and experimental study Type P1 Proceeding
Year 2016 Publication Hakone Xv: International Symposium On High Pressure Low Temperature Plasma Chemistry: With Joint Cost Td1208 Workshop: Non-equilibrium Plasmas With Liquids For Water And Surface Treatment Abbreviated Journal
Volume Issue Pages
Keywords P1 Proceeding; Laboratory of adsorption and catalysis (LADCA); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In recent years there is increased interest in plasma-based CO2 conversion. Several plasma setups are being investigated for this purpose, but the most commonly used ones are a dielectric barrier discharge (DBD), a microwave (MW) plasma and a gliding arc (GA) reactor. In this proceedings paper, we will show results from our experiments in a (packed bed) DBD reactor and in a vortex-flow GA reactor, as well as from our model calculations for the detailed plasma chemistry in a DBD, MW and GA, for pure CO2 as well as mixtures of CO2 with N-2, CH4 and H2O.
Address
Corporate Author Thesis
Publisher Masarykova univ Place of Publication Brno Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 978-80-210-8318-9 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:141553 Serial 4526
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Author Houssa, M.; van den Broek, B.; Scalise, E.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A.
Title Theoretical study of silicene and germanene Type P1 Proceeding
Year 2013 Publication Graphene, Ge/iii-v, And Emerging Materials For Post Cmos Applications 5 Abbreviated Journal
Volume Issue Pages
Keywords P1 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The structural and electronic properties of silicene and germanene on metallic and non-metallic substrates are investigated theoretically, using first-principles simulations. We first study the interaction of silicene with Ag(111) surfaces, focusing on the (4x4) silicene/Ag structure. Due to symmetry breaking in the silicene layer (nonequivalent number of top and bottom Si atoms), silicene is predicted to be semiconducting, with a computed energy gap of about 0.3 eV. However, the charge transfer occurring at the silicene/Ag(111) interface leads to an overall metallic system. We next investigate the interaction of silicene and germanene with hexagonal non-metallic substrates, namely ZnS and ZnSe. On reconstructed (semiconducting) (0001) ZnS or ZnSe surfaces, silicene and germanene are found to be semiconducting. Remarkably, the nature (indirect or direct) and magnitude of their energy band gap can be controlled by an out-of-plane electric field.
Address
Corporate Author Thesis
Publisher Electrochemical soc inc Place of Publication Pennington Editor
Language Wos 000354468000006 Publication Date 2013-05-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 978-1-60768-374-2; 978-1-62332-023-2 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 6 Open Access
Notes Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:134451 Serial 4529
Permanent link to this record
 

 
Author N. Gauquelin, E. Benckiser, M. K. Kinyanjui, M. Wu, Y. Lu, G. Christiani, G. Logvenov, H.-U. Habermeier, U. Kaiser, B. Keimer, and G. A. Botton
Title Atomically resolved EELS mapping of the interfacial structure of epitaxially strained LaNiO3/LaAlO3 superlattices Type A1 Journal Article
Year 2014 Publication Physical Review B Abbreviated Journal
Volume 90 Issue Pages 195140
Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
Abstract The interfacial atomic structure of a metallic LaNiO3/LaAlO3 superlattice grown on a LaSrAlO4 substrate was

investigated using a combination of atomically resolved electron energy loss spectroscopy (EELS) at the Al K,

Al L2,3, Sr L2,3, Ni L2,3, La M4,5, and O K edges as well as hybridization mapping of selected features of the O

K-edge fine structure.We observe an additional La1−xSrxAl1−yNiyO3 layer at the substrate-superlattice interface,

possibly linked to diffusion of Al and Sr into the growing film or a surface reconstruction due to Sr segregation.

The roughness of the LaNiO3/LaAlO3 interfaces is found to be on average around one pseudocubic unit cell. The

O K-edge EELS spectra revealed reduced spectral weight of the prepeak derived from Ni-O hybridized states in

the LaNiO3 layers. We rule out oxygen nonstoichiometry of the LaNiO3 layers and discuss changes in the Ni-O

hybridization due to heterostructuring as possible origin.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000345467000003 Publication Date 2014-11-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links
Impact Factor Times cited 17 Open Access
Notes Approved (down) Most recent IF: NA
Call Number EMAT @ emat @ Serial 4544
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Author M. K. Kinyanjui, N. Gauquelin, E. Benckiser, H. –U. Habermeier, B. Keimer, U. Kaiser and G.A. Botton
Title Local lattice distortion and anisotropic modulation in Epitaxially Strained LaNiO3/LaAlO3 hetero-structures Type A1 Journal Article
Year 2014 Publication Applied Physics Letters Abbreviated Journal
Volume 104 Issue Pages 221909
Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
Abstract Using a complementary combination of x-ray diffraction and atomically resolved imaging we investigated the lattice structure of epitaxial LaNiO3/LaAlO3 superlattices grown on a compressive-strain inducing LaSrAlO4 (001) substrate. A refinement of the structure obtained from the x-ray data revealed the monoclinic I 2/c 1 1 space group. The (Ni/Al)O6 octahedral rotation angle perpendicular to the superlattice plane is enhanced, and the one parallel to the plane is reduced with respect to the corresponding bulk values. High-angle annular dark field imaging was used to determine the lattice parameters within the superlattice unit cell. High-resolution electron microscopy images of the oxygen atoms are consistent with the x-ray results.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000337161700029 Publication Date 2014-06-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links
Impact Factor Times cited 22 Open Access
Notes Approved (down) Most recent IF: NA
Call Number EMAT @ emat @ Serial 4545
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Author Petrovic, M.
Title Characterization of scanning gate technique and transport in nanostructured graphene Type Doctoral thesis
Year 2017 Publication Abbreviated Journal
Volume Issue Pages
Keywords Doctoral thesis; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Antwerpen Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:144015 Serial 4590
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Author Hafiz, H.; Suzuki, K.; Barbiellini, B.; Orikasa, Y.; Callewaert, V.; Kaprzyk, S.; Itou, M.; Yamamoto, K.; Yamada, R.; Uchimoto, Y.; Sakurai, Y.; Sakurai, H.; Bansil, A.
Title Visualizing redox orbitals and their potentials in advanced lithium-ion battery materials using high-resolution x-ray Compton scattering Type A1 Journal article
Year 2017 Publication Science Advances Abbreviated Journal Sci. Adv.
Volume 3 Issue 8 Pages e1700971
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Reduction-oxidation (redox) reactions are the key processes that underlie the batteries powering smartphones, laptops, and electric cars. A redox process involves transfer of electrons between two species. For example, in a lithium-ion battery, current is generated when conduction electrons from the lithium anode are transferred to the redox orbitals of the cathode material. The ability to visualize or image the redox orbitals and how these orbitals evolve under lithiation and delithiation processes is thus of great fundamental and practical interest for understanding the workings of battery materials. We show that inelastic scattering spectroscopy using high-energy x-ray photons (Compton scattering) can yield faithful momentum space images of the redox orbitals by considering lithium iron phosphate (LiFePO4 or LFP) as an exemplar cathode battery material. Our analysis reveals a new link between voltage and the localization of transition metal 3d orbitals and provides insight into the puzzling mechanism of potential shift and how it is connected to the modification of the bond between the transition metal and oxygen atoms. Our study thus opens a novel spectroscopic pathway for improving the performance of battery materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000411589900055 Publication Date 2017-08-24
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 9 Open Access
Notes The work at Northeastern University was supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (grant no. DE-FG02-07ER46352) and benefited from the Northeastern University’s Advanced Scientific Computation Center and the National Energy Research Scientific Computing Center supercomputing center through DOE grant no. DEAC02-05CH11231. The work at Gunma University, Japan Synchrotron Radiation Research Institute (JASRI), and Kyoto University was supported by the Japan Science and Technology Agency. K.S. was supported by Grant-in-Aid for Young Scientists (B) from MEXT KAKENHI under grant nos. 24750065 and 15K17873. The Compton scattering experiments were performed with the approval of JASRI (proposal no. 2014A1289). V.C. was supported by the FWO-Vlaanderen through project no. G. 1161 0224.14N. Approved (down) Most recent IF: NA
Call Number CMT @ cmt @c:irua:145034 Serial 4637
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Author Mikhailova, D.; Kuratieva, N.N.; Utsumi, Y.; Tsirlin, A.A.; Abakumov, A.M.; Schmidt, M.; Oswald, S.; Fuess, H.; Ehrenberg, H.
Title Composition-dependent charge transfer and phase separation in the V1-xRexO2 solid solution Type A1 Journal article
Year 2017 Publication Journal of the Chemical Society : Dalton transactions Abbreviated Journal
Volume 46 Issue 5 Pages 1606-1617
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The substitution of vanadium in vanadium dioxide VO2 influences the critical temperatures of structural and metal-to-insulator transitions in different ways depending on the valence of the dopant. Rhenium adopts valence states between + 4 and + 7 in an octahedral oxygen surrounding and is particularly interesting in this context. Structural investigation of V1-xRexO2 solid solutions (0.01 <= x <= 0.30) between 80 and 1200 K using synchrotron X-ray powder diffraction revealed only two polymorphs that resemble VO2: the low-temperature monoclinic MoO2-type form (space group P2(1)/c), and the tetragonal rutile-like form (space group P4(2)/mnm). However, for compositions with 0.03 < x <= 0.15 a phase separation in the solid solution was observed below 1000 K upon cooling down from 1200 K, giving rise to two isostructural phases with slightly different lattice parameters. This is reflected in the appearance of two metal-toinsulator transition temperatures detected by magnetization and specific heat measurements. Comprehensive X-ray photoelectron spectroscopy studies showed that an increased amount of Re leads to a change in the Re valence state from solely Re6+ at a low doping level (<= 3 at% Re) via mixed-valence states Re4+/Re6+ for at least 0.03 < x <= 0.10, up to nearly pure Re4+ in V0.70Re0.30O2. Thus, compositions V1-xRexO2 with only one valence state of Re in the material (Re6+ or Re4+) can be obtained as a single phase, while intermediate compositions are subjected to a phase separation, presumably due to different valence states of Re.
Address
Corporate Author Thesis
Publisher Place of Publication London Editor
Language Wos 000395442700030 Publication Date 2016-12-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0300-9246; 1477-9226; 1472-7773 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.029 Times cited 1 Open Access Not_Open_Access
Notes ; The authors are indebted to Dr G. Auffermann (Max Planck Institute for Chemical Physics of Solids, Dresden, Germany) for performing the ICP-OES analyses. This research has received a partial funding from the BMBF, project grant number 03SF0477B (DESIREE). AT acknowledges financial support from Federal Ministry for Education and Research under Sofja Kovalevksaya Award of Alexander von Humboldt Foundation. AMA is grateful to the Russian Science Foundation (grant 14-13-00680) for financial support. ; Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:142580 Serial 4642
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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 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 (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:142452 Serial 4666
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Author Shestakov, M.V.; Meledina, M.; Turner, S.; Baekelant, W.; Verellen, N.; Chen, X.; Hofkens, J.; Van Tendeloo, G.; Moshchalkov, V.V.
Title Luminescence of fixed site Ag nanoclusters in a simple oxyfluoride glass host and plasmon absorption of amorphous Ag nanoparticles in a complex oxyfluoride glass host Type P1 Proceeding
Year 2015 Publication Proceedings of the Society of Photo-optical Instrumentation Engineers T2 – 8th International Conference on Photonics, Devices, and System VI, AUG 27-29, 2014, Prague, CZECH REPUBLIC Abbreviated Journal
Volume Issue Pages Unsp 94501n
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract Ag nanocluster-doped glasses have been prepared by a conventional melt-quenching method. The effect of melt temperature and dwell time on the formation of Ag nanoclusters and Ag nanoparticles in simple host oxyfluoride glasses has been studied. The increase of melt temperature and dwell time results in the dissolution of Ag nanoparticles and substantial red-shift of absorption and photoluminescence spectra of the prepared glasses. The quantum yield of the glasses is similar to 5% and does not depend on melt temperature and dwell time. The prepared glasses may be used as red phosphors or down-conversion layers for solar-cells.
Address
Corporate Author Thesis
Publisher Spie-int soc optical engineering Place of Publication Bellingham Editor
Language Wos 000349404500057 Publication Date 2015-01-06
Series Editor Series Title Abbreviated Series Title
Series Volume 9450 Series Issue Edition
ISSN 978-1-62841-566-7 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:144783 Serial 4668
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Author Verhulst, A.S.; Verreck, D.; Smets, Q.; Kao, K.-H.; Van de Put, M.; Rooyackers, R.; Sorée, B.; Vandooren, A.; De Meyer, K.; Groeseneken, G.; Heyns, M.M.; Mocuta, A.; Collaert, N.; Thean, A.V.-Y.
Title Perspective of tunnel-FET for future low-power technology nodes Type P1 Proceeding
Year 2014 Publication 2014 Ieee International Electron Devices Meeting (iedm) Abbreviated Journal
Volume Issue Pages
Keywords P1 Proceeding; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Ieee Place of Publication New york Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 978-1-4799-8000-0 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:144789 Serial 4679
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Author Alania, M.
Title Quantification of 3D atomic positions for nanoparticles using scanning transmission electron microscopy: statistical parameter estimation, dose-limited precision and optimal experimental design Type Doctoral thesis
Year 2017 Publication Abbreviated Journal
Volume Issue Pages
Keywords Doctoral thesis; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Antwerpen Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:144014 Serial 4682
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Author Sieger, M.; Pahlke, P.; Lao, M.; Eisterer, M.; Meledin, A.; Van Tendeloo, G.; Ottolinger, R.; Haenisch, J.; Holzapfel, B.; Usoskin, A.; Kursumovic, A.; MacManus-Driscoll, J.L.; Stafford, B.H.; Bauer, M.; Nielsch, K.; Schultz, L.; Huehne, R.
Title Tailoring microstructure and superconducting properties in thick BaHfO3 and Ba2YNb/Ta)O-6 doped YBCO films on technical templates Type A1 Journal article
Year 2017 Publication IEEE transactions on applied superconductivity Abbreviated Journal
Volume 27 Issue 4 Pages 6601407
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The current transport capability of YBa2Cu3O7-x(YBCO) based coated conductors (CCs) is mainly limited by two features: the grain boundaries of the used textured template, which are transferred into the superconducting film through the buffer layers, and the ability to pin magnetic flux lines by incorporation of defined defects in the crystal lattice. By adjusting the deposition conditions, it is possible to tailor the pinning landscape in doped YBCO in order to meet specific working conditions (T, B) for CC applications. To study these effects, we deposited YBCO layers with a thickness of about 1-2 mu m using pulsed laser deposition on buffered rolling-assisted biaxially textured Ni-W substrates as well as on metal tapes having either an ion-beam-texturedYSZbuffer or an MgO layer textured by inclined substrate deposition. BaHfO3 and the mixed double-perovskite Ba2Y(Nb/Ta)O-6 were incorporated as artificial pinning centers in these YBCO layers. X-ray diffraction confirmed the epitaxial growth of the superconductor on these templates as well as the biaxially oriented incorporation of the secondary phase additions in the YBCO matrix. A critical current density J(c) of more than 2 MA/cm(2) was achieved at 77 K in self-field for 1-2 mu m thick films. Detailed TEM (transmission electron microscopy) studies revealed that the structure of the secondary phase can be tuned, forming c-axis aligned nanocolumns, ab-oriented platelets, or a combination of both. Transport measurements show that the J(c) anisotropy in magnetic fields is reduced by doping and the peak in the J(c) (theta) curves can be correlated to the microstructural features.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000394588100001 Publication Date 2016-12-24
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1051-8223 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 12 Open Access OpenAccess
Notes ; This work was supported by EUROTAPES, a collaborative project funded by the European Commission's Seventh Framework Program (FP7/2007-2013) under Grant Agreement no. 280432. ; Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:141961 Serial 4693
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Author Mirzakhani, M.
Title Electronic properties and energy levels of graphene quantum dots Type Doctoral thesis
Year 2017 Publication Abbreviated Journal
Volume Issue Pages
Keywords Doctoral thesis; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Antwerpen Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:147179 Serial 4781
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Author Sathiya, M.; Jacquet, Q; Doublet, M.L; Karakulina, O.M.; Hadermann, J.; Tarascon, J.-M.
Title A Chemical Approach to Raise Cell Voltage and Suppress Phase Transition in O3 Sodium Layered Oxide Electrodes Type A1 Journal article
Year 2018 Publication Advanced energy materials Abbreviated Journal Adv. Energy Mater.
Volume Issue Pages
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Sodium ion batteries (NIBs) are one of the versatile technologies for lowcost rechargeable batteries. O3-type layered sodium transition metal oxides (NaMO2, M = transition metal ions) are one of the most promising positive electrode materials considering their capacity. However, the use of O3 phases is limited due to their low redox voltage and associated multiple phase transitions which are detrimental for long cycling. Herein, a simple strategy is proposed to successfully combat these issues. It consists of the introduction of a larger, nontransition metal ion Sn4+ in NaMO2 to prepare a series of NaNi0.5Mn0.5−y SnyO2 (y = 0–0.5) compositions with attractive electrochemical performances, namely for y = 0.5, which shows a single-phase transition from O3 ⇔ P3 at the very end of the oxidation process. Na-ion NaNi0.5Sn0.5O2/C coin cells are shown to deliver an average cell voltage of 3.1 V with an excellent capacity retention as compared to an average stepwise voltage of ≈2.8 V and limited capacity retention for the pure NaNi0.5Mn0.5O2 phase. This study potentially shows the way to manipulate the O3 NaMO2 for facilitating their practical use in NIBs.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000430163100013 Publication Date 2018-01-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 21.875 Times cited 28 Open Access OpenAccess
Notes M.S. and Q.J. contributed equally to this work. The authors thank Dr. Daniel Alves Dalla Corte and Sujoy Saha for electronic conductivity measurements and Prof. Dominique Larcher for fruitful discussions. Q.J. thanks the ANR “Deli-Redox” for Ph.D. funding. J.-M.T. acknowledges funding from the European Research Council (ERC) (FP/2014)/ERC Grant-Project 670116-ARPEMA. TGA analysis by Matthieu Courty, LRCS, Amiens, is greatly acknowledged. J.H. and O.M.K. acknowledge funding from FWO Vlaanderen project G040116N. Approved (down) Most recent IF: NA
Call Number EMAT @ emat @c:irua:149515 Serial 4907
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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 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 (down) 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 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 (down) 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 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 (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:150838UA @ admin @ c:irua:150838 Serial 4964
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Author Roxana Vlad, V.; Bartolome, E.; Vilardell, M.; Calleja, A.; Meledin, A.; Obradors, X.; Puig, T.; Ricart, S.; Van Tendeloo, G.; Usoskin, A.; Lee, S.; Petrykin, V.; Molodyk, A.
Title Inkjet printing multideposited YBCO on CGO/LMO/MgO/Y2O3/Al2O3/Hastelloy tape for 2G-coated conductors Type A1 Journal article
Year 2018 Publication IEEE transactions on applied superconductivity Abbreviated Journal
Volume 28 Issue 4 Pages 6601805
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We present the preparation of a new architecture of coated conductor by Inkjet printing of low fluorine YBa2Cu3O7-x (YBCO) on top of SuperOx tape: CGO/LMO/IBAD-MgO/Y2O3/Al-2 O-3/Hastelloy. A five-layered multideposited, 475-nm-thick YBCO film was structurally and magnetically characterized. A good texture was achieved using this combination of buffer layers, requiring only a 30-nm-thin ion-beam-assisted deposition (IBAD)-MgO layer. The LF-YBCO CC reaches self-field critical current density values of J(c)(GB) similar to NJ 15.9 MA/cm(2) (5 K), similar to 1.23 MA/cm(2) (77 K) corresponding to an I-c (77 K) = 58.4 A/cm-width. Inkjet printing offers a flexible and cost effective method for YBCO deposition, allowing patterning of structures.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000429010900001 Publication Date 2018-02-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1051-8223 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.288 Times cited 2 Open Access Not_Open_Access
Notes ; This work was performed within the framework of the EUROTAPES Project FP7-NMP.2011.2.2-1 under Grant280432, funded by the EU. ICMAB research was financed by the Ministry of Economy and Competitiveness, and FEDER funds under Projects MAT2011-28874-C02-01, MAT2014-51778-C2-1-R, ENE2014-56109-C3-3-R, and Consolider Nanoselect CSD2007-00041, and by Generalitat de Catalunya (2009 SGR 770, 2015 SGR 753, and Xarmae). ICMAB acknowledges support from Severo Ochoa Program (MINECO) under Grant SEV-2015-0496. ; Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:150711 Serial 4971
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Author Pourtois, G.; Dabral, A.; Sankaran, K.; Magnus, W.; Yu, H.; de de Meux, A.J.; Lu, A.K.A.; Clima, S.; Stokbro, K.; Schaekers, M.; Houssa, M.; Collaert, N.; Horiguchi, N.
Title Probing the intrinsic limitations of the contact resistance of metal/semiconductor interfaces through atomistic simulations Type P1 Proceeding
Year 2017 Publication Semiconductors, Dielectrics, And Metals For Nanoelectronics 15: In Memory Of Samares Kar Abbreviated Journal
Volume Issue Pages 303-311
Keywords P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract In this contribution, we report a fundamental study of the factors that set the contact resistivity between metals and highly doped semiconductors. We investigate the case of n-type doped Si contacted with amorphous TiSi combining first-principles calculations with Non-Equilibrium Green functions transport simulations. The intrinsic contact resistivity is found to saturate at similar to 2x10(-10) Omega.cm(2) with the doping concentration and sets an intrinsic limit to the ultimate contact resistance achievable for n-doped Si vertical bar amorphous-TiSi. This limit arises from the intrinsic properties of the semiconductor and of the metal such as their electron effective masses and Fermi energies. We illustrate that, in this regime, contacting metals with a heavy electron effective mass helps reducing the interface intrinsic contact resistivity.
Address
Corporate Author Thesis
Publisher Electrochemical soc inc Place of Publication Pennington Editor
Language Wos 000426271800028 Publication Date 2017-10-17
Series Editor Series Title Abbreviated Series Title
Series Volume 80 Series Issue 1 Edition
ISSN 978-1-62332-470-4; 978-1-60768-818-1 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 1 Open Access Not_Open_Access
Notes ; ; Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:149966 Serial 4976
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Author Verreck, D.; Verhulst, A.S.; Van de Put, M.L.; Sorée, B.; Magnus, W.; Collaert, N.; Mocuta, A.; Groeseneken, G.
Title Self-consistent 30-band simulation approach for (non-)uniformly strained confined heterostructure tunnel field-effect transistors Type P1 Proceeding
Year 2017 Publication Simulation of Semiconductor Processes and, Devices (SISPAD)AND DEVICES (SISPAD 2017) Abbreviated Journal
Volume Issue Pages 29-32
Keywords P1 Proceeding; Condensed Matter Theory (CMT)
Abstract Heterostructures of III-V materials under a mechanical strain are being actively researched to enhance the performance of the tunnel field-effect transistor (TFET). In scaled III-V device structures, however, the interplay between the effects of strain and quantum confinement on the semiconductor band structure and hence the performance is highly non-trivial. We have therefore developed a computationally efficient quantum mechanical simulator Pharos, which enables self-consistent full-zone k.p-based simulations of III-V TFETs under a general non-uniform strain. We present the self-consistent procedure and demonstrate it on confined staggered bandgap GaAs0.5Sb0.5/In0.53Ga0.47As TFETs. We find a large performance degradation due to size-induced quantum confinement compared to non-confined devices. We show that some performance can be regained either by applying a uniform biaxial tensile strain or through the non-uniform strain profile at a lattice-mismatched heterostructure.
Address
Corporate Author Thesis
Publisher Ieee Place of Publication New york Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 978-4-86348-610-2 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved (down) Most recent IF: NA
Call Number UA @ lucian @ c:irua:149949 Serial 4978
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