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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 (up) 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 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
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Author Willhammar, T.; Sentosun, K.; Mourdikoudis, S.; Goris, B.; Kurttepeli, M.; Bercx, M.; Lamoen, D.; Partoens, B.; Pastoriza-Santos, I.; Pérez-Juste, J.; Liz-Marzán, L.M.; Bals, S.; Van Tendeloo, G.
  Title (up) Structure and vacancy distribution in copper telluride nanoparticles influence plasmonic activity in the near-infrared Type A1 Journal article
  Year 2017 Publication Nature communications Abbreviated Journal Nat Commun
  Volume 8 Issue 8 Pages 14925
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
  Abstract Copper chalcogenides find applications in different domains including photonics, photothermal therapy and photovoltaics. CuTe nanocrystals have been proposed as an alternative to noble metal particles for plasmonics. Although it is known that deviations from stoichiometry are a prerequisite for plasmonic activity in the near-infrared, an accurate description of the material and its (optical) properties is hindered by an insufficient understanding of the atomic structure and the influence of defects, especially for materials in their nanocrystalline form. We demonstrate that the structure of Cu1.5±xTe nanocrystals canbe determined using electron diffraction tomography. Real-space high-resolution electron tomography directly reveals the three-dimensional distribution of vacancies in the structure. Through first-principles density functional theory, we furthermore demonstrate that the influence of these vacancies on the optical properties of the nanocrystals is determined. Since our methodology is applicable to a variety of crystalline nanostructured materials, it is expected to provide unique insights concerning structure–property correlations.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000397799700001 Publication Date 2017-03-30
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 12.124 Times cited 37 Open Access OpenAccess
  Notes The work was financially supported by the European Research Council through an ERC Starting Grant (#335078-COLOURATOMS). T.W. acknowledges the Swedish Research Council for an international postdoc grant. We acknowledge financial support of FWO-Vlaanderen through project G.0216.14N, G.0369.15N and a postdoctoral research grant to B.G. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government–Department EWI. The work was further supported by the Spanish MINECO (MAT2013-45168-R). S.M. thanks the Action ooSupporting Postdoctoral Researchers44 of the Operational Program ‘Education and Lifelong Learning’ (Action’s Beneficiary: General Secretariat for Research and Technology of Greece), which was co-financed by the European Social Fund (ESF) and the Greek State. (ROMEO:green; preprint:; postprint:can ; pdfversion:can); ECAS_Sara Approved Most recent IF: 12.124
  Call Number EMAT @ emat @ c:irua:142203UA @ admin @ c:irua:142203 Serial 4538
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Author Lyu, Y.-Y.; Jiang, J.; Wang, Y.-L.; Xiao, Z.-L.; Dong, S.; Chen, Q.-H.; Milošević, M.V.; Wang, H.; Divan, R.; Pearson, J.E.; Wu, P.; Peeters, F.M.; Kwok, W.-K.
  Title (up) Superconducting diode effect via conformal-mapped nanoholes Type A1 Journal article
  Year 2021 Publication Nature Communications Abbreviated Journal Nat Commun
  Volume 12 Issue 1 Pages 2703
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
  Abstract A superconducting diode is an electronic device that conducts supercurrent and exhibits zero resistance primarily for one direction of applied current. Such a dissipationless diode is a desirable unit for constructing electronic circuits with ultralow power consumption. However, realizing a superconducting diode is fundamentally and technologically challenging, as it usually requires a material structure without a centre of inversion, which is scarce among superconducting materials. Here, we demonstrate a superconducting diode achieved in a conventional superconducting film patterned with a conformal array of nanoscale holes, which breaks the spatial inversion symmetry. We showcase the superconducting diode effect through switchable and reversible rectification signals, which can be three orders of magnitude larger than that from a flux-quantum diode. The introduction of conformal potential landscapes for creating a superconducting diode is thereby proven as a convenient, tunable, yet vastly advantageous tool for superconducting electronics. This could be readily applicable to any superconducting materials, including cuprates and iron-based superconductors that have higher transition temperatures and are desirable in device applications. A superconducting diode is dissipationless and desirable for electronic circuits with ultralow power consumption, yet it remains challenging to realize it. Here, the authors achieve a superconducting diode in a conventional superconducting film patterned with a conformal array of nanoscale holes.
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  Publisher Place of Publication Editor
  Language Wos 000658724200018 Publication Date 2021-05-11
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 12.124 Times cited 71 Open Access OpenAccess
  Notes Approved Most recent IF: 12.124
  Call Number UA @ admin @ c:irua:179611 Serial 7024
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Author Litzius, K.; Leliaert, J.; Bassirian, P.; Rodrigues, D.; Kromin, S.; Lemesh, I.; Zazvorka, J.; Lee, K.-J.; Mulkers, J.; Kerber, N.; Heinze, D.; Keil, N.; Reeve, R.M.; Weigand, M.; Van Waeyenberge, B.; Schuetz, G.; Everschor-Sitte, K.; Beach, G.S.D.; Klaeui, M.
  Title (up) The role of temperature and drive current in skyrmion dynamics Type A1 Journal article
  Year 2020 Publication Nature Electronics Abbreviated Journal
  Volume 3 Issue 1 Pages 30-36
  Keywords A1 Journal article; Condensed Matter Theory (CMT)
  Abstract Magnetic skyrmions are topologically stabilized nanoscale spin structures that could be of use in the development of future spintronic devices. When a skyrmion is driven by an electric current it propagates at an angle relative to the flow of current-known as the skyrmion Hall angle (SkHA)-that is a function of the drive current. This drive dependence, as well as thermal effects due to Joule heating, could be used to tailor skyrmion trajectories, but are not well understood. Here we report a study of skyrmion dynamics as a function of temperature and drive amplitude. We find that the skyrmion velocity depends strongly on temperature, while the SkHA does not and instead evolves differently in the low- and high-drive regimes. In particular, the maximum skyrmion velocity in ferromagnetic devices is limited by a mechanism based on skyrmion surface tension and deformation (where the skyrmion transitions into a stripe). Our mechanism provides a complete description of the SkHA in ferromagnetic multilayers across the full range of drive strengths, illustrating that skyrmion trajectories can be engineered for device applications. An analysis of skyrmion dynamics at different temperatures and electric drive currents is used to develop a complete description of the skyrmion Hall angle in ferromagnetic multilayers from the creep to the flow regime and illustrates that skyrmion trajectories can be engineered for device applications.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000510860800012 Publication Date 2020-01-24
  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 Times cited 11 Open Access
  Notes ; ; Approved Most recent IF: NA
  Call Number UA @ admin @ c:irua:167863 Serial 6625
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Author Neek-Amal, M.; Xu, P.; Schoelz, J.K.; Ackerman, M.L.; Barber, S.D.; Thibado, P.M.; Sadeghi, A.; Peeters, F.M.
  Title (up) Thermal mirror buckling in freestanding graphene locally controlled by scanning tunnelling microscopy Type A1 Journal article
  Year 2014 Publication Nature communications Abbreviated Journal Nat Commun
  Volume 5 Issue Pages 4962
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
  Abstract Knowledge of and control over the curvature of ripples in freestanding graphene are desirable for fabricating and designing flexible electronic devices, and recent progress in these pursuits has been achieved using several advanced techniques such as scanning tunnelling microscopy. The electrostatic forces induced through a bias voltage (or gate voltage) were used to manipulate the interaction of freestanding graphene with a tip (substrate). Such forces can cause large movements and sudden changes in curvature through mirror buckling. Here we explore an alternative mechanism, thermal load, to control the curvature of graphene. We demonstrate thermal mirror buckling of graphene by scanning tunnelling microscopy and large-scale molecular dynamic simulations. The negative thermal expansion coefficient of graphene is an essential ingredient in explaining the observed effects. This new control mechanism represents a fundamental advance in understanding the influence of temperature gradients on the dynamics of freestanding graphene and future applications with electro-thermal-mechanical nanodevices.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000342984800018 Publication Date 2014-09-17
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2041-1723; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 12.124 Times cited 36 Open Access
  Notes ; Financial support for this study was provided, in part, by the Office of Naval Research under grant N00014-10-1-0181, the National Science Foundation under grant DMR-0855358, the EU-Marie Curie IIF postdoc Fellowship/299855 (for M. N.-A.), the ESF-EuroGRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. M.N.-A. has also been supported partially by BOF project of University of Antwerp number 28033. ; Approved Most recent IF: 12.124; 2014 IF: 11.470
  Call Number UA @ lucian @ c:irua:121121 Serial 3628
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Author Van Aert, S.; Batenburg, K.J.; Rossell, M.D.; Erni, R.; Van Tendeloo, G.
  Title (up) Three-dimensional atomic imaging of crystalline nanoparticles Type A1 Journal article
  Year 2011 Publication Nature Abbreviated Journal Nature
  Volume 470 Issue 7334 Pages 374-377
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
  Abstract Determining the three-dimensional (3D) arrangement of atoms in crystalline nanoparticles is important for nanometre-scale device engineering and also for applications involving nanoparticles, such as optoelectronics or catalysis. A nanoparticles physical and chemical properties are controlled by its exact 3D morphology, structure and composition1. Electron tomography enables the recovery of the shape of a nanoparticle from a series of projection images2, 3, 4. Although atomic-resolution electron microscopy has been feasible for nearly four decades, neither electron tomography nor any other experimental technique has yet demonstrated atomic resolution in three dimensions. Here we report the 3D reconstruction of a complex crystalline nanoparticle at atomic resolution. To achieve this, we combined aberration-corrected scanning transmission electron microscopy5, 6, 7, statistical parameter estimation theory8, 9 and discrete tomography10, 11. Unlike conventional electron tomography, only two images of the targeta silver nanoparticle embedded in an aluminium matrixare sufficient for the reconstruction when combined with available knowledge about the particles crystallographic structure. Additional projections confirm the reliability of the result. The results we present help close the gap between the atomic resolution achievable in two-dimensional electron micrographs and the coarser resolution that has hitherto been obtained by conventional electron tomography.
  Address
  Corporate Author Thesis
  Publisher Place of Publication London Editor
  Language Wos 000287409100037 Publication Date 2011-02-02
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 0028-0836;1476-4687; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 40.137 Times cited 341 Open Access
  Notes Esteem 026019 Approved Most recent IF: 40.137; 2011 IF: 36.280
  Call Number UA @ lucian @ c:irua:86745 Serial 3644
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Author Wang, H.S.; Chen, L.; Elibol, K.; He, L.; Wang, H.; Chen, C.; Jiang, C.; Li, C.; Wu, T.; Cong, C.X.; Pennycook, T.J.; Argentero, G.; Zhang, D.; Watanabe, K.; Taniguchi, T.; Wei, W.; Yuan, Q.; Meyer, J.C.; Xie, X.
  Title (up) Towards chirality control of graphene nanoribbons embedded in hexagonal boron nitride Type A1 Journal article
  Year 2020 Publication Nature Materials Abbreviated Journal Nat Mater
  Volume Issue Pages 1-10
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Oriented trenches are created in h-BN using different catalysts, and used as templates to grow seamlessly integrated armchair and zigzag graphene nanoribbons with chirality-dependent electrical and magnetic conductance properties. The integrated in-plane growth of graphene nanoribbons (GNRs) and hexagonal boron nitride (h-BN) could provide a promising route to achieve integrated circuitry of atomic thickness. However, fabrication of edge-specific GNRs in the lattice of h-BN still remains a significant challenge. Here we developed a two-step growth method and successfully achieved sub-5-nm-wide zigzag and armchair GNRs embedded in h-BN. Further transport measurements reveal that the sub-7-nm-wide zigzag GNRs exhibit openings of the bandgap inversely proportional to their width, while narrow armchair GNRs exhibit some fluctuation in the bandgap-width relationship. An obvious conductance peak is observed in the transfer curves of 8- to 10-nm-wide zigzag GNRs, while it is absent in most armchair GNRs. Zigzag GNRs exhibit a small magnetic conductance, while armchair GNRs have much higher magnetic conductance values. This integrated lateral growth of edge-specific GNRs in h-BN provides a promising route to achieve intricate nanoscale circuits.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000571692500001 Publication Date 2020-09-21
  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 41.2 Times cited 3 Open Access Not_Open_Access
  Notes ; H.W. and X.X. thank J.H. Edgar (Kansas State University, USA) for supplying the partial h-BN crystals. H. S. Wang, L. Chen and H. Wang thank M. Liu, X. Qiu and J. Pan from NCNT of China, F. Liou, H. Tsai, M. Crommie from UCB, USA, J. Xue and P. Yu from ShanghaiTech University and S. Wang from SJTU for nc-AFM measurement. H. S. Wang, L. Chen and H. Wang thank B. Sun and S. Li from Hunan University for the fusion of the STEM image and the electron energy loss spectroscopy mapping images. Funding: The work was partially supported by the National Key R&D program (Grant No. 2017YFF0206106), the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No. XDB30000000), the National Science Foundation of China (Grant No. 51772317, 51302096, 61774040, 91964102), the Science and Technology Commission of Shanghai Municipality (Grant No. 16ZR1442700, 16ZR1402500 18511110700), Shanghai Rising-Star Program (A type) (Grant No.18QA1404800), the Hubei Provincial Natural Science Foundation of China (Grant No. ZRMS2017000370), China Postdoctoral Science Foundation (Grant No. 2017M621563, 2018T110415), and the Fundamental Research Funds of Wuhan City (No. 2016060101010075). C.L. acknowledges support from the European Union's Horizon 2020 research and innovation programme under the Marie Skodowska-Curie grants No. 656378 – Interfacial Reactions. T.J.P. acknowledges funding from European Union's Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie grant agreement no. 655760-DIGIPHASE. K.W. and T.T. acknowledge support from the Elemental Strategy Initiative conducted by the MEXT, Japan and the CREST (JPMJCR15F3), JST. C.X.C. acknowledges financial support from the National Young 1000 Talent Plan of China and the National Key R&D Program of China (No. 2018YFA0703700). L.H. acknowledges financial support from the programme of China Scholarships Council (No. 201706160037). ; Approved Most recent IF: 41.2; 2020 IF: 39.737
  Call Number UA @ admin @ c:irua:171944 Serial 6633
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Author Bourgeois, L.; Zhang, Y.; Zhang, Z.; Chen, Y.; Medhekar, N., V
  Title (up) Transforming solid-state precipitates via excess vacancies Type A1 Journal article
  Year 2020 Publication Nature Communications Abbreviated Journal Nat Commun
  Volume 11 Issue 1 Pages 1248
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Many phase transformations associated with solid-state precipitation look structurally simple, yet, inexplicably, take place with great difficulty. A classic case of difficult phase transformations is the nucleation of strengthening precipitates in high-strength lightweight aluminium alloys. Here, using a combination of atomic-scale imaging, simulations and classical nucleation theory calculations, we investigate the nucleation of the strengthening phase theta' onto a template structure in the aluminium-copper alloy system. We show that this transformation can be promoted in samples exhibiting at least one nanoscale dimension, with extremely high nucleation rates for the strengthening phase as well as for an unexpected phase. This template-directed solid-state nucleation pathway is enabled by the large influx of surface vacancies that results from heating a nanoscale solid. Template-directed nucleation is replicated in a bulk alloy as well as under electron irradiation, implying that this difficult transformation can be facilitated under the general condition of sustained excess vacancy concentrations.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000549162600025 Publication Date 2020-03-06
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 16.6 Times cited 5 Open Access OpenAccess
  Notes ; The authors are indebted to Matthew Weyland for his expert advice on aberrationcorrected scanning transmission electron microscopy. L.B. would like to acknowledge initial discussions with B.C. Muddle and J.F. Nie many years ago regarding the possible thermodynamic role of vacancies in solid-state precipitation. The authors acknowledge funding from the Australian Research Council (LE0454166, LE110100223), the Victorian State Government and Monash University for instrumentation, and use of the facilities within the Monash Centre for Electron Microscopy. The authors thank Flame Burgmann, Dougal McCulloch and Edwin Mayes for access to and assistance at the Microscopy and Microanalysis Facility at RMIT University. L.B. and N.M. acknowledge the financial support of the Australian Research Council (DP150100558). Authors also gratefully acknowledge the computational support from MonARCH, MASSIVE and the National Computing Infrastructure and Pawsey Supercomputing Centre. ZZ and YZ are thankful to Monash University for a Monash Graduate Scholarship, a Monash International Postgraduate Research Scholarship. Z.Z. is grateful for a Monash Centre for Electron Microscopy Postgraduate Scholarship. The authors are grateful to Anita Hill for advice. ; Approved Most recent IF: 16.6; 2020 IF: 12.124
  Call Number UA @ admin @ c:irua:170797 Serial 6635
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Author Hu, S.; Gopinadhan, K.; Rakowski, A.; Neek-Amal, M.; Heine, T.; Grigorieva, I.V.; Haigh, S.J.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M.
  Title (up) Transport of hydrogen isotopes through interlayer spacing in van der Waals crystals Type A1 Journal article
  Year 2018 Publication Nature nanotechnology Abbreviated Journal Nat Nanotechnol
  Volume 13 Issue 6 Pages 468-+
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
  Abstract Atoms start behaving as waves rather than classical particles if confined in spaces commensurate with their de Broglie wavelength. At room temperature this length is only about one angstrom even for the lightest atom, hydrogen. This restricts quantum-confinement phenomena for atomic species to the realm of very low temperatures(1-5). Here, we show that van der Waals gaps between atomic planes of layered crystals provide angstrom-size channels that make quantum confinement of protons apparent even at room temperature. Our transport measurements show that thermal protons experience a notably higher barrier than deuterons when entering van der Waals gaps in hexagonal boron nitride and molybdenum disulfide. This is attributed to the difference in the de Broglie wavelengths of the isotopes. Once inside the crystals, transport of both isotopes can be described by classical diffusion, albeit with unexpectedly fast rates comparable to that of protons in water. The demonstrated angstrom-size channels can be exploited for further studies of atomistic quantum confinement and, if the technology can be scaled up, for sieving hydrogen isotopes.
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  Corporate Author Thesis
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  Language Wos 000434715700015 Publication Date 2018-04-04
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1748-3387; 1748-3395 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 38.986 Times cited 32 Open Access
  Notes ; The authors acknowledge support from the Lloyd's Register Foundation, EPSRC – EP/N010345/1, the European Research Council ARTIMATTER project – ERC-2012-ADG and from Graphene Flagship. M.L.-H. acknowledges a Leverhulme Early Career Fellowship. ; Approved Most recent IF: 38.986
  Call Number UA @ lucian @ c:irua:152014UA @ admin @ c:irua:152014 Serial 5046
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Author Jiang, Y.; Mao, J.; Moldovan, D.; Masir, M.R.; Li, G.; Watanabe, K.; Taniguchi, T.; Peeters, F.M.; Andrei, E.Y.
  Title (up) Tuning a circular p-n junction in graphene from quantum confinement to optical guiding Type A1 Journal article
  Year 2017 Publication Nature nanotechnology Abbreviated Journal Nat Nanotechnol
  Volume 12 Issue 11 Pages 1045-+
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
  Abstract <script type='text/javascript'>document.write(unpmarked('The photon-like propagation of the Dirac electrons in graphene, together with its record-high electronic mobility(1-3), can lead to applications based on ultrafast electronic response and low dissipation(4-6). However, the chiral nature of the charge carriers that is responsible for the high mobility also makes it difficult to control their motion and prevents electronic switching. Here, we show how to manipulate the charge carriers by using a circular p-n junction whose size can be continuously tuned from the nanometre to the micrometre scale(7,8). The junction size is controlled with a dual-gate device consisting of a planar back gate and a point-like top gate made by decorating a scanning tunnelling microscope tip with a gold nanowire. The nanometre-scale junction is defined by a deep potential well created by the tip-induced charge. It traps the Dirac electrons in quantum-confined states, which are the graphene equivalent of the atomic collapse states (ACSs) predicted to occur at supercritically charged nuclei(9-13). As the junction size increases, the transition to the optical regime is signalled by the emergence of whispering-gallery modes(14-16), similar to those observed at the perimeter of acoustic or optical resonators, and by the appearance of a Fabry-Perot interference pattern(17-20) for junctions close to a boundary.'));
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  Publisher Place of Publication Editor
  Language Wos 000414531800011 Publication Date 2017-09-15
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1748-3387; 1748-3395 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 38.986 Times cited 65 Open Access
  Notes ; The authors acknowledge funding provided by DOE-FG02-99ER45742 (STM/STS) and NSF DMR 1708158 (fabrication). Theoretical work was supported by ESF-EUROCORES-EuroGRAPHENE, FWO VI and the Methusalem program of the Flemish government. ; Approved Most recent IF: 38.986
  Call Number UA @ lucian @ c:irua:147406 Serial 4902
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Author Talgorn, E.; Gao, Y.; Aerts, M.; Kunneman, L.T.; Schins, J.M.; Savenije, T.J.; van Huis, M.A.; van der Zant, H.S.J.; Houtepen, A.J.; Siebbeles, L.D.A.
  Title (up) Unity quantum yield of photogenerated charges and band-like transport in quantum-dot solids Type A1 Journal article
  Year 2011 Publication Nature nanotechnology Abbreviated Journal Nat Nanotechnol
  Volume 6 Issue 11 Pages 733-739
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
  Abstract Solid films of colloidal quantum dots show promise in the manufacture of photodetectors and solar cells. These devices require high yields of photogenerated charges and high carrier mobilities, which are difficult to achieve in quantum-dot films owing to a strong electronhole interaction and quantum confinement. Here, we show that the quantum yield of photogenerated charges in strongly coupled PbSe quantum-dot films is unity over a large temperature range. At high photoexcitation density, a transition takes place from hopping between localized states to band-like transport. These strongly coupled quantum-dot films have electrical properties that approach those of crystalline bulk semiconductors, while retaining the size tunability and cheap processing properties of colloidal quantum dots.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000296737300012 Publication Date 2011-09-25
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 1748-3387;1748-3395; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 38.986 Times cited 129 Open Access
  Notes Approved Most recent IF: 38.986; 2011 IF: 27.270
  Call Number UA @ lucian @ c:irua:93296 Serial 3813
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Author Wu, K.; Torun, E.; Sahin, H.; Chen, B.; Fan, X.; Pant, A.; Wright, D.P.; Aoki, T.; Peeters, F.M.; Soignard, E.; Tongay, S.
  Title (up) Unusual lattice vibration characteristics in whiskers of the pseudo-one-dimensional titanium trisulfide TiS3 Type A1 Journal article
  Year 2016 Publication Nature communications Abbreviated Journal Nat Commun
  Volume 7 Issue Pages 12952
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
  Abstract Transition metal trichalcogenides form a class of layered materials with strong in-plane anisotropy. For example, titanium trisulfide (TiS3) whiskers are made out of weakly interacting TiS3 layers, where each layer is made of weakly interacting quasi-one-dimensional chains extending along the b axis. Here we establish the unusual vibrational properties of TiS3 both experimentally and theoretically. Unlike other two-dimensional systems, the Raman active peaks of TiS3 have only out-of-plane vibrational modes, and interestingly some of these vibrations involve unique rigid-chain vibrations and S-S molecular oscillations. High-pressure Raman studies further reveal that the A(g)(S-S) S-S molecular mode has an unconventional negative pressure dependence, whereas other peaks stiffen as anticipated. Various vibrational modes are doubly degenerate at ambient pressure, but the degeneracy is lifted at high pressures. These results establish the unusual vibrational properties of TiS3 with strong in-plane anisotropy, and may have relevance to understanding of vibrational properties in other anisotropic two-dimensional material systems.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000385444300004 Publication Date 2016-09-22
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 12.124 Times cited 50 Open Access
  Notes ; S.T. acknowledges support from the National Science Foundation (DMR-1552220) and (CMMI-1561839). F.M.P., H.S. and E.T. were supported by the Flemish Science Foundation (FWO-Vl). Computational resources were partially provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e Infrastructure). H.S. acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP programme. F.P. acknowledges the funding from Flemish Science Foundation (FWO-Vl). K.W. acknowledges helpful discussions with H. Cai, W. Kong and X. Meng. We gratefully acknowledge the use of facilities within the LeRoy Eyring Center for Solid State Science at Arizona State University. ; Approved Most recent IF: 12.124
  Call Number UA @ lucian @ c:irua:144662 Serial 4700
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Author Xu, P.; Neek-Amal, M.; Barber, S.D.; Schoelz, J.K.; Ackerman, M.L.; Thibado, P.M.; Sadeghi, A.; Peeters, F.M.
  Title (up) Unusual ultra-low-frequency fluctuations in freestanding graphene Type A1 Journal article
  Year 2014 Publication Nature communications Abbreviated Journal Nat Commun
  Volume 5 Issue Pages 3720
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
  Abstract Intrinsic ripples in freestanding graphene have been exceedingly difficult to study. Individual ripple geometry was recently imaged using scanning tunnelling microscopy, but these measurements are limited to static configurations. Thermally-activated flexural phonon modes should generate dynamic changes in curvature. Here we show how to track the vertical movement of a one-square-angstrom region of freestanding graphene using scanning tunnelling microscopy, thereby allowing measurement of the out-of-plane time trajectory and fluctuations over long time periods. We also present a model from elasticity theory to explain the very-low-frequency oscillations. Unexpectedly, we sometimes detect a sudden colossal jump, which we interpret as due to mirror buckling. This innovative technique provides a much needed atomic-scale probe for the time-dependent behaviours of intrinsic ripples. The discovery of this novel progenitor represents a fundamental advance in the use of scanning tunnelling microscopy, which together with the application of a thermal load provides a low-frequency nano-resonator.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000335223200007 Publication Date 2014-04-28
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2041-1723; ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 12.124 Times cited 62 Open Access
  Notes ; This work was financially supported, in part, by the Office of Naval Research under grant N00014-10-1-0181, the National Science Foundation under grant DMR-0855358, the EU-Marie Curie IIF postdoc Fellowship/299855 (for M.N.-A.), the ESF-Euro-GRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; Approved Most recent IF: 12.124; 2014 IF: 11.470
  Call Number UA @ lucian @ c:irua:117201 Serial 3819
Permanent link to this record
 

 
Author Van Echelpoel, R.; De Wael, K.
  Title (up) Voltammetric drug testing makes sense at the border Type A1 Journal article
  Year 2024 Publication Nature Reviews Chemistry Abbreviated Journal
  Volume Issue Pages 1-2
  Keywords A1 Journal article; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
  Abstract The European BorderSens project leverages voltammetric sensors, developed with end-users' input, to rapidly and accurately detect illicit drugs. By embracing practicalities and validation, this technology has the potential to combat the illicit drug problem.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 001142000900001 Publication Date 2024-01-12
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2397-3358 ISBN Additional Links UA library record; WoS full record
  Impact Factor Times cited Open Access Not_Open_Access
  Notes Approved Most recent IF: NA
  Call Number UA @ admin @ c:irua:202646 Serial 9112
Permanent link to this record
 

 
Author Mefford, J.T.; Rong, X.; Abakumov, A.M.; Hardin, W.G.; Dai, S.; Kolpak, A.M.; Johnston, K.P.; Stevenson, K.J.
  Title (up) Water electrolysis on La1-xSrxCoO3-\delta perovskite electrocatalysts Type A1 Journal article
  Year 2016 Publication Nature communications Abbreviated Journal Nat Commun
  Volume 7 Issue 7 Pages 11053
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
  Abstract Perovskite oxides are attractive candidates as catalysts for the electrolysis of water in alkaline energy storage and conversion systems. However, the rational design of active catalysts has been hampered by the lack of understanding of the mechanism of water electrolysis on perovskite surfaces. Key parameters that have been overlooked include the role of oxygen vacancies, B-O bond covalency, and redox activity of lattice oxygen species. Here we present a series of cobaltite perovskites where the covalency of the Co-O bond and the concentration of oxygen vacancies are controlled through Sr2+ substitution into La1 – xSrxCoO3 – delta. We attempt to rationalize the high activities of La1 – xSrxCoO3 – delta through the electronic structure and participation of lattice oxygen in the mechanism of water electrolysis as revealed through ab initio modelling. Using this approach, we report a material, SrCoO2.7, with a high, room temperature-specific activity and mass activity towards alkaline water electrolysis.
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  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000372721700001 Publication Date 2016-03-23
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 12.124 Times cited 278 Open Access
  Notes Financial support for this work was provided by the R.A. Welch Foundation (grants F-1529 and F-1319). X.R. and A.M.K. acknowledge support from the Skoltech-MIT Center for Electrochemical Energy Storage. Computations were performed using computational resources from XSEDE and NERSC. S.D. was supported as part of the Fluid Interface Reactions, Structures and Transport (FIRST) Center, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, and Office of Basic Energy Sciences. We thank D.W. Redman for help with the RHE measurements. Approved Most recent IF: 12.124
  Call Number UA @ lucian @ c:irua:133242 Serial 4276
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Author Cai, J.; Griffin, E.; Guarochico-Moreira, V.H.; Barry, D.; Xin, B.; Yagmurcukardes, M.; Zhang, S.; Geim, A.K.; Peeters, F.M.; Lozada-Hidalgo, M.
  Title (up) Wien effect in interfacial water dissociation through proton-permeable graphene electrodes Type A1 Journal article
  Year 2022 Publication Nature communications Abbreviated Journal Nat Commun
  Volume 13 Issue 1 Pages 5776-5777
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
  Abstract Strong electric fields can accelerate molecular dissociation reactions. The phenomenon known as the Wien effect was previously observed using high-voltage electrolysis cells that produced fields of about 10(7) V m(-1), sufficient to accelerate the dissociation of weakly bound molecules (e.g., organics and weak electrolytes). The observation of the Wien effect for the common case of water dissociation (H2O reversible arrow H+ + OH-) has remained elusive. Here we study the dissociation of interfacial water adjacent to proton-permeable graphene electrodes and observe strong acceleration of the reaction in fields reaching above 10(8) V m(-1). The use of graphene electrodes allows measuring the proton currents arising exclusively from the dissociation of interfacial water, while the electric field driving the reaction is monitored through the carrier density induced in graphene by the same field. The observed exponential increase in proton currents is in quantitative agreement with Onsager's theory. Our results also demonstrate that graphene electrodes can be valuable for the investigation of various interfacial phenomena involving proton transport.
  Address
  Corporate Author Thesis
  Publisher Place of Publication Editor
  Language Wos 000862552600012 Publication Date 2022-10-01
  Series Editor Series Title Abbreviated Series Title
  Series Volume Series Issue Edition
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles
  Impact Factor 16.6 Times cited 14 Open Access OpenAccess
  Notes Approved Most recent IF: 16.6
  Call Number UA @ admin @ c:irua:191575 Serial 7228
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