Records |
Author |
Singh, V.; Mehta, B.R.; Sengar, S.K.; Karakulina, O.M.; Hadermann, J.; Kaushal, A. |
Title |
Achieving independent control of core diameter and carbon shell thickness in Pd-C core–shell nanoparticles by gas phase synthesis |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
Volume |
28 |
Issue |
29 |
Pages |
295603 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Pd-C core–shell nanoparticles with independently controllable core size and shell thickness are grown by gas phase synthesis. First, the core size is selected by electrical mobility values of charged particles, and second, the shell thickness is controlled by the concentration of carbon precursor gas. The carbon shell grows by adsorption of carbon precursor gas molecules on the surface of nanoparticles, followed by sintering. The presence of a carbon shell on Pd nanoparticles is potentially important in hydrogen-related applications operating at high temperatures or in catalytic reactions in acidic/aqueous environments. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000404633200002 |
Publication Date |
2017-06-28 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.44 |
Times cited |
1 |
Open Access |
Not_Open_Access |
Notes |
VS is thankful to the All India Council for Technical Education, India, for providing assistantship under its Quality Improvement Programme. BRM gratefully acknowledges the support of the Nanomission Programme of the Department of Science and Technology (DST), India and Schlumberger Chair Professorship. BRM would also like to acknowledge the support from the project funded by BRNS, DAE, India. |
Approved |
Most recent IF: 3.44 |
Call Number |
EMAT @ emat @c:irua:144831 |
Serial |
4712 |
Permanent link to this record |
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Author |
Zhang, R.; Wu, Z.; Li, X.J.; Li, L.L.; Chen, Q.; Li, Y.-M.; Peeters, F.M. |
Title |
Fano resonances in bilayer phosphorene nanoring |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
Volume |
29 |
Issue |
21 |
Pages |
215202 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Tunable transport properties and Fano resonances are predicted in a circular bilayer phosphorene nanoring. The conductance exhibits Fano resonances with varying incident energy and applied perpendicular magnetic field. These Fano resonance peaks can be accurately fitted with the well known Fano curves. When a magnetic field is applied to the nanoring, the conductance oscillates periodically with magnetic field which is reminiscent of the Aharonov-Bohm effect. Fano resonances are tightly related to the discrete states in the central nanoring, some of which are tunable by the magnetic field. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000428920200001 |
Publication Date |
2018-03-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.44 |
Times cited |
4 |
Open Access |
|
Notes |
; This work was supported by Grant No. 2017YFA0303400 from the National Key R&D Program of China, the Flemish Science Foundation, the grants No. 2016YFE0110000, No. 2015CB921503, and No. 2016YFA0202300 from the MOST of China, the NSFC (Grants Nos. 11504366, 11434010, 61674145 and 61774168) and CAS (Grants No. QYZDJ-SSW-SYS001). ; |
Approved |
Most recent IF: 3.44 |
Call Number |
UA @ lucian @ c:irua:150713UA @ admin @ c:irua:150713 |
Serial |
4968 |
Permanent link to this record |
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Author |
Aierken, Y.; Sevik, C.; Gulseren, O.; Peeters, F.M.; Çakir, D. |
Title |
In pursuit of barrierless transition metal dichalcogenides lateral heterojunctions |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
Volume |
29 |
Issue |
29 |
Pages |
295202 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
There is an increasing need to understand interfaces between two-dimensional materials to realize an energy efficient boundary with low contact resistance and small heat dissipation. In this respect, we investigated the impact of charge and substitutional atom doping on the electronic transport properties of the hybrid metallic-semiconducting lateral junctions, formed between metallic (1T and 1T(d)) and semiconducting (1H) phases of MoS2 by means of first-principles and non-equilibrium Green function formalism based calculations. Our results clearly revealed the strong influence of the type of interface and crystallographic orientation of the metallic phase on the transport properties of these systems. The Schottky barrier height, which is the dominant mechanism for contact resistance, was found to be as large as 0.63 eV and 1.19 eV for holes and electrons, respectively. We found that armchair interfaces are more conductive as compared to zigzag termination due to the presence of the metallic Mo zigzag chains that are directed along the transport direction. In order to manipulate these barrier heights we investigated the influence of electron doping of the metallic part (i.e. 1T(d) -MoS2). We observed that the Fermi level of the hybrid system moves towards the conduction band of semiconducting 1H-MoS2 due to filling of 4d-orbital of metallic MoS2, and thus the Schottky barrier for electrons decreases considerably. Besides electron doping, we also investigated the effect of substitutional doping of metallic MoS2 by replacing Mo atoms with either Re or Ta. Due to its valency, Re (Ta) behaves as a donor (acceptor) and reduces the Schottky barrier for electrons (holes). Since Re and Ta based transition metal dichalcogenides crystallize in either the 1T(d) or 1T phase, substitutional doping with these atom favors the stabilization of the 1T(d) phase of MoS2. Co-doping of hybrid structure results in an electronic structure, which facilities easy dissociation of excitons created in the 1H part. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000432823800002 |
Publication Date |
2018-05-01 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.44 |
Times cited |
4 |
Open Access |
|
Notes |
; This work was supported by the bilateral project between the The Scientific and Technological Research Council of Turkey (TUBITAK) and FWO-Flanders, Flemish Science Foundation (FWO-VI) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TRGrid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. We acknowledge the support from TUBITAK (Grant No. 115F024). ; |
Approved |
Most recent IF: 3.44 |
Call Number |
UA @ lucian @ c:irua:151451UA @ admin @ c:irua:151451 |
Serial |
5029 |
Permanent link to this record |
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Author |
Shah, N.A.; Li, L.L.; Mosallanejad, V.; Peeters, F.M.; Guo, G.-P. |
Title |
Transport characteristics of multi-terminal pristine and defective phosphorene systems |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
Volume |
30 |
Issue |
45 |
Pages |
455705 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Atomic vacancies and nanopores act as local scattering centers and modify the transport properties of charge carriers in phosphorene nanoribbons (PNRs). We investigate the influence of such atomic defects on the electronic transport of multi-terminal PNR. We use the non-equilibrium Green's function approach within the tight-binding framework to calculate the transmission coefficient and the conductance. Terminals induce band mixing resulting in oscillations in the conductance. In the presence of atomic vacancies and nanopores the conductance between non-axial terminals exhibit constructive scattering, which is in contrast to mono-axial two-terminal systems where the conductance exhibits destructive scattering. This can be understood from the spatial local density of states of the transport modes in the system. Our results provide fundamental insights into the electronic transport in PNR-based multi-terminal systems and into the ability of atomic defects and nanopores through tuning the transport properties. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000483049100001 |
Publication Date |
2019-08-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.44 |
Times cited |
8 |
Open Access |
|
Notes |
; This work was supported by the National Key Research and Development Program of China (Grant No. 2016YFA0301700), the NNSFC (Grant No. 11625419), the Strategic Priority Research Program of the CAS (Grant Nos. XDB24030601 and XDB30000000), the Anhui initiative in Quantum information Technologies (Grants No. AHY080000), and the Flemish Science Foundation (FWO-Vl). This work was also supported by the Chinese Academy of Sciences and the World Academy of Science for the advancement of science in developing countries. ; |
Approved |
Most recent IF: 3.44 |
Call Number |
UA @ admin @ c:irua:162760 |
Serial |
5429 |
Permanent link to this record |
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Author |
Mehta, A.N.; Gauquelin, N.; Nord, M.; Orekhov, A.; Bender, H.; Cerbu, D.; Verbeeck, J.; Vandervorst, W. |
Title |
Unravelling stacking order in epitaxial bilayer MX₂ using 4D-STEM with unsupervised learning |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
Volume |
31 |
Issue |
44 |
Pages |
445702 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Following an extensive investigation of various monolayer transition metal dichalcogenides (MX2), research interest has expanded to include multilayer systems. In bilayer MX2, the stacking order strongly impacts the local band structure as it dictates the local confinement and symmetry. Determination of stacking order in multilayer MX(2)domains usually relies on prior knowledge of in-plane orientations of constituent layers. This is only feasible in case of growth resulting in well-defined triangular domains and not useful in-case of closed layers with hexagonal or irregularly shaped islands. Stacking order can be discerned in the reciprocal space by measuring changes in diffraction peak intensities. Advances in detector technology allow fast acquisition of high-quality four-dimensional datasets which can later be processed to extract useful information such as thickness, orientation, twist and strain. Here, we use 4D scanning transmission electron microscopy combined with multislice diffraction simulations to unravel stacking order in epitaxially grown bilayer MoS2. Machine learning based data segmentation is employed to obtain useful statistics on grain orientation of monolayer and stacking in bilayer MoS2. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000561424400001 |
Publication Date |
2020-07-14 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.5 |
Times cited |
13 |
Open Access |
OpenAccess |
Notes |
; J.V. acknowledges funding from FLAG-ERA JTC2017 project 'Graph-Eye'. N.G. acknowledges funding from GOA project 'Solarpaint' of the University of Antwerp. This project has received funding from the European Union's Horizon 2020 research and innovation programme under Grant Agreement No. 823717-ESTEEM3. 4D STEM data was acquired on a hybrid pixel detector funded with a Hercules fund 'Direct electron detector for soft matter TEM' from the Flemish Government. M. N. acknowledges funding from a Marie Curie Fellowship agreement No 838001. We thank Dr Jiongjiong Mo and Dr Benjamin Groven for developing the CVD-MoS<INF>2</INF> growth on sapphire and providing the material used in this article. ; |
Approved |
Most recent IF: 3.5; 2020 IF: 3.44 |
Call Number |
UA @ admin @ c:irua:171119 |
Serial |
6649 |
Permanent link to this record |
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Author |
Bafekry, A.; Shahrokhi, M.; Shafique, A.; Jappor, H.R.; Shojaei, F.; Feghhi, S.A.H.; Ghergherehchi, M.; Gogova, D. |
Title |
Two-dimensional carbon nitride C₆N nanosheet with egg-comb-like structure and electronic properties of a semimetal |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
Volume |
32 |
Issue |
21 |
Pages |
215702 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
In this study, the structural, electronic and optical properties of theoretically predicted C6N monolayer structure are investigated by means of Density Functional Theory-based First-Principles Calculations. Phonon band dispersion calculations and molecular dynamics simulations reveal the dynamical and thermal stability of the C6N single-layer structure. We found out that the C6N monolayer has large negative in-plane Poisson's ratios along both X and Y direction and the both values are almost four times that of the famous-pentagraphene. The electronic structure shows that C6N monolayer is a semi-metal and has a Dirac-point in the BZ. The optical analysis using the random phase approximation method constructed over HSE06 illustrates that the first peak of absorption coefficient of the C6N monolayer along all polarizations is located in the IR range of spectrum, while the second absorption peak occurs in the visible range, which suggests its potential applications in optical and electronic devices. Interestingly, optically anisotropic character of this system is highly desirable for the design of polarization-sensitive photodetectors. Thermoelectric properties such as Seebeck coefficient, electrical conductivity, electronic thermal conductivity and power factor are investigated as a function of carrier doping at temperatures 300, 400, and 500 K. In general, we predict that the C6N monolayer could be a new platform for study of novel physical properties in two-dimensional semi-metal materials, which may provide new opportunities to realize high-speed low-dissipation devices. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000624531500001 |
Publication Date |
2020-12-18 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.44 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 3.44 |
Call Number |
UA @ admin @ c:irua:176648 |
Serial |
6740 |
Permanent link to this record |
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Author |
Parastaev, A.; Muravev, V.; Osta, E.H.; Kimpel, T.F.; Simons, J.F.M.; van Hoof, A.J.F.; Uslamin, E.; Zhang, L.; Struijs, J.J.C.; Burueva, D.B.; Pokochueva, E.V.; Kovtunov, K.V.; Koptyug, I.V.; Villar-Garcia, I.J.; Escudero, C.; Altantzis, T.; Liu, P.; Béché, A.; Bals, S.; Kosinov, N.; Hensen, E.J.M. |
Title |
Breaking structure sensitivity in CO2 hydrogenation by tuning metal–oxide interfaces in supported cobalt nanoparticles |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Nature Catalysis |
Abbreviated Journal |
Nat Catal |
Volume |
5 |
Issue |
11 |
Pages |
1051-1060 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
Abstract |
A high dispersion of the active metal phase of transition metals on oxide supports is important when designing efficient heterogeneous catalysts. Besides nanoparticles, clusters and even single metal atoms can be attractive for a wide range of reactions. However, many industrially relevant catalytic transformations suffer from structure sensitivity, where reducing the size of the metal particles below a certain size substantially lowers catalytic performance. A case in point is the low activity of small cobalt nanoparticles in the hydrogenation of CO and CO2. Here we show how engineering of catalytic sites at the metal–oxide interface in cerium oxide–zirconium dioxide (ceria–zirconia)-supported cobalt can overcome this structure sensitivity. Few-atom cobalt clusters dispersed on 3 nm cobalt(II)-oxide particles stabilized by ceria–zirconia yielded a highly active CO2 methanation catalyst with a specific activity higher than that of larger particles under the same conditions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000884939300006 |
Publication Date |
2022-11-17 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2520-1158 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
37.8 |
Times cited |
32 |
Open Access |
OpenAccess |
Notes |
This research was supported by the Applied and Engineering Sciences division of the Netherlands Organization for Scientific Research through the Alliander (now Qirion) Perspective program on Plasma Conversion of CO2. We acknowledge Diamond Light Source for time on beamline B18 under proposal SP20715-1. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. S.B. acknowledges support from the European Research Council (ERC Consolidator Grant #815128 REALNANO) and T.A. acknowledges funding from the University of Antwerp Research fund (BOF). A.B. received funding from the European Union under grant agreement No 823717 – ESTEEM3. The authors acknowledge funding through the Hercules grant (FWO, University of Antwerp) I003218N “Infrastructure for imaging nanoscale processes in gas/vapour or liquid environments”. I.V.K., D.B.B., and E.V.P. acknowledge the Russian Ministry of Science and Higher Education (contract 075-15-2021-580) for financial support of parahydrogen-based studies. Experiments using synchrotron radiation XPS were performed at the CIRCE beamline at ALBA Synchrotron with the collaboration of ALBA staff. F. Oropeza Palacio and Rim C.J. van de Poll are acknowledged for the help with RPES measurements.; esteem3reported; esteem3jra |
Approved |
Most recent IF: 37.8 |
Call Number |
EMAT @ emat @c:irua:192068 |
Serial |
7230 |
Permanent link to this record |
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Author |
Ovsyannikov, S.V.; Bykov, M.; Bykova, E.; Kozlenko, D.P.; Tsirlin, A.A.; Karkin, A.E.; Shchennikov, V.V.; Kichanov, S.E.; Gou, H.; Abakumov, A.M.; Egoavil, R.; Verbeeck, J.; McCammon, C.; Dyadkin, V.; Chernyshov, D.; van Smaalen, S.; Dubrovinsky, L.S. |
Title |
Charge-ordering transition in iron oxide Fe4O5 involving competing dimer and trimer formation |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Nature chemistry |
Abbreviated Journal |
Nat Chem |
Volume |
8 |
Issue |
8 |
Pages |
501-508 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Phase transitions that occur in materials, driven, for instance, by changes in temperature or pressure, can dramatically change the materials' properties. Discovering new types of transitions and understanding their mechanisms is important not only from a fundamental perspective, but also for practical applications. Here we investigate a recently discovered Fe4O5 that adopts an orthorhombic CaFe3O5-type crystal structure that features linear chains of Fe ions. On cooling below approximately 150 K, Fe4O5 undergoes an unusual charge-ordering transition that involves competing dimeric and trimeric ordering within the chains of Fe ions. This transition is concurrent with a significant increase in electrical resistivity. Magnetic-susceptibility measurements and neutron diffraction establish the formation of a collinear antiferromagnetic order above room temperature and a spin canting at 85 K that gives rise to spontaneous magnetization. We discuss possible mechanisms of this transition and compare it with the trimeronic charge ordering observed in magnetite below the Verwey transition temperature. |
Address |
Bayerisches Geoinstitut, Universitat Bayreuth, Universitatsstrasse 30, D-95447, Bayreuth, Germany |
Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
English |
Wos |
000374534100019 |
Publication Date |
2016-04-04 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
1755-4330 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
25.87 |
Times cited |
51 |
Open Access |
|
Notes |
S.V.O. acknowledges the financial support of the Deutsche Forschungsgemeinschaft (DFG) under project OV-110/1-3. A.E.K. and V.V.S. acknowledge the support of the Russian Foundation for Basic Research (Project 14–02–00622a). H.G. acknowledges the support from the Alexander von Humboldt (AvH) Foundation and the National Natural Science Foundation of China (No. 51201148). A.M.A., R.E. and J.V. acknowledge financial support from the European Commission (EC) under the Seventh Framework Programme (FP7) under a contract for an Integrated Infrastructure Initiative, Reference No. 312483- ESTEEM2. R.E. acknowledges support from the EC under FP7 Grant No. 246102 IFOX. A.M.A. acknowledges funding from the Russian Science Foundation (Grant No. 14-13- 00680). A.A.T. acknowledges funding and from the Federal Ministry for Education and Research through the Sofja Kovalevkaya Award of the AvH Foundation. Funding from the Fund for Scientific Research Flanders under FWO Project G.0044.13N is acknowledged. M.B. and S.v.S. acknowledge support from the DFG under Project Sm55/15-2. We acknowledge the European Synchrotron Radiation Facility for the provision of synchrotron radiation facilities.; esteem2jra2; esteem2jra3 |
Approved |
Most recent IF: 25.87 |
Call Number |
c:irua:133593 c:irua:133593UA @ admin @ c:irua:133593 |
Serial |
4068 |
Permanent link to this record |
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Author |
O'Sullivan, M.; Hadermann, J.; Dyer, M.S.; Turner, S.; Alaria, J.; Manning, T.D.; Abakumov, A.M.; Claridge, J.B.; Rosseinsky, M.J. |
Title |
Interface control by chemical and dimensional matching in an oxide heterostructure |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Nature chemistry |
Abbreviated Journal |
Nat Chem |
Volume |
8 |
Issue |
8 |
Pages |
347-353 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Interfaces between different materials underpin both new scientific phenomena, such as the emergent behaviour at oxide interfaces, and key technologies, such as that of the transistor. Control of the interfaces between materials with the same crystal structures but different chemical compositions is possible in many materials classes, but less progress has been made for oxide materials with different crystal structures. We show that dynamical self-organization during growth can create a coherent interface between the perovskite and fluorite oxide structures, which are based on different structural motifs, if an appropriate choice of cations is made to enable this restructuring. The integration of calculation with experimental observation reveals that the interface differs from both the bulk components and identifies the chemical bonding requirements to connect distinct oxide structures. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000372505500013 |
Publication Date |
2016-02-01 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1755-4330; 1755-4349 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
25.87 |
Times cited |
28 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 25.87 |
Call Number |
UA @ lucian @ c:irua:133189 |
Serial |
4199 |
Permanent link to this record |
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Author |
Zhou, Y.; Che, F.; Liu, M.; Zou, C.; Liang, Z.; De Luna, P.; Yuan, H.; Li, J.; Wang, Z.; Xie, H.; Li, H.; Chen, P.; Bladt, E.; Quintero-Bermudez, R.; Sham, T.-K.; Bals, S.; Hofkens, J.; Sinton, D.; Chen, G.; Sargent, E.H. |
Title |
Dopant-induced electron localization drives CO2 reduction to C2 hydrocarbons |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Nature chemistry |
Abbreviated Journal |
Nat Chem |
Volume |
10 |
Issue |
10 |
Pages |
974-980 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The electrochemical reduction of CO2 to multi-carbon products has attracted much attention because it provides an avenue to the synthesis of value-added carbon-based fuels and feedstocks using renewable electricity. Unfortunately, the efficiency of CO2 conversion to C-2 products remains below that necessary for its implementation at scale. Modifying the local electronic structure of copper with positive valence sites has been predicted to boost conversion to C-2 products. Here, we use boron to tune the ratio of Cu delta+ to Cu-0 active sites and improve both stability and C-2-product generation. Simulations show that the ability to tune the average oxidation state of copper enables control over CO adsorption and dimerization, and makes it possible to implement a preference for the electrosynthesis of C-2 products. We report experimentally a C-2 Faradaic efficiency of 79 +/- 2% on boron-doped copper catalysts and further show that boron doping leads to catalysts that are stable for in excess of similar to 40 hours while electrochemically reducing CO2 to multi-carbon hydrocarbons. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000442395200013 |
Publication Date |
2018-07-13 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1755-4330; 1755-4349 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
25.87 |
Times cited |
700 |
Open Access |
OpenAccess |
Notes |
; This work was supported financially by funding from TOTAL S.A., the Ontario Research Fund: Research Excellence Program, the Natural Sciences and Engineering Research Council of Canada, the CIFAR Bio-Inspired Solar Energy programme, a University of Toronto Connaught grant, the Ministry of Science, Natural Science Foundation of China (21471040, 21271055 and 21501035), the Innovation-Driven Plan in Central South University project (2017CX003), a project from State Key Laboratory of Powder Metallurgy in Central South University, the Thousand Youth Talents Plan of China and Hundred Youth Talents Program of Hunan and the China Scholarship Council programme. This work benefited from the soft X-ray microcharacterization beamline at CLS, sector 20BM at the APS and the Ontario Centre for the Characterisation of Advanced Materials at the University of Toronto. H.Y. acknowledges financial support from the Research Foundation-Flanders (FWO postdoctoral fellowship). C.Z. acknowledges support from the International Academic Exchange Fund for Joint PhD Students from Tianjin University. P.D.L. acknowledges financial support from the Natural Sciences and Engineering Research Council in the form of the Canada Graduate Scholarship-Doctoral award. S.B. and E.B. acknowledge financial support from the European Research Council (ERC Starting Grant # 335078-COLOURATOMS). The authors thank B. Zhang, N. Wang, C. T. Dinh, T. Zhuang, J. Li and Y. Zhao for fruitful discussions, as well as Y. Hu and Q. Xiao from CLS, and Z. Finfrock and M. Ward from APS for their help during the course of study. Computations were performed on the SOSCIP Consortium's Blue Gene/Q computing platform. SOSCIP is funded by the Federal Economic Development Agency of Southern Ontario, the Province of Ontario, IBM Canada, Ontario Centres of Excellence, Mitacs and 15 Ontario academic member institutions. ; ecas_sara |
Approved |
Most recent IF: 25.87 |
Call Number |
UA @ lucian @ c:irua:153693UA @ admin @ c:irua:153693 |
Serial |
5091 |
Permanent link to this record |
|
|
|
Author |
Mueller, K.; Krause, F.F.; Béché, A.; Schowalter, M.; Galioit, V.; Loeffler, S.; Verbeeck, J.; Zweck, J.; Schattschneider, P.; Rosenauer, A. |
Title |
Atomic electric fields revealed by a quantum mechanical approach to electron picodiffraction |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
5 |
Issue |
|
Pages |
5653 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
By focusing electrons on probes with a diameter of 50 pm, aberration-corrected scanning transmission electron microscopy (STEM) is currently crossing the border to probing subatomic details. A major challenge is the measurement of atomic electric fields using differential phase contrast (DPC) microscopy, traditionally exploiting the concept of a field- induced shift of diffraction patterns. Here we present a simplified quantum theoretical interpretation of DPC. This enables us to calculate the momentum transferred to the STEM probe from diffracted intensities recorded on a pixel array instead of conventional segmented bright- field detectors. The methodical development yielding atomic electric field, charge and electron density is performed using simulations for binary GaN as an ideal model system. We then present a detailed experimental study of SrTiO3 yielding atomic electric fields, validated by comprehensive simulations. With this interpretation and upgraded instrumentation, STEM is capable of quantifying atomic electric fields and high-contrast imaging of light atoms. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000347227700003 |
Publication Date |
2014-12-15 |
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 |
197 |
Open Access |
|
Notes |
246791 COUNTATOMS; 278510 VORTEX; Hercules; 312483 ESTEEM2; esteem2ta; ECASJO; |
Approved |
Most recent IF: 12.124; 2014 IF: 11.470 |
Call Number |
UA @ lucian @ c:irua:122835UA @ admin @ c:irua:122835 |
Serial |
166 |
Permanent link to this record |
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|
Author |
Bals, S.; Van Aert, S.; Romero, C.P.; Lauwaet, K.; Van Bael, M.J.; Schoeters, B.; Partoens, B.; Yuecelen, E.; Lievens, P.; Van Tendeloo, G. |
Title |
Atomic scale dynamics of ultrasmall germanium clusters |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
3 |
Issue |
897 |
Pages |
897 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
Starting from the gas phase, small clusters can be produced and deposited with huge flexibility with regard to composition, materials choice and cluster size. Despite many advances in experimental characterization, a detailed morphology of such clusters is still lacking. Here we present an atomic scale observation as well as the dynamical behaviour of ultrasmall germanium clusters. Using quantitative scanning transmission electron microscopy in combination with ab initio calculations, we are able to characterize the transition between different equilibrium geometries of a germanium cluster consisting of less than 25 atoms. Seven-membered rings, trigonal prisms and some smaller subunits are identified as possible building blocks that stabilize the structure. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000306099900024 |
Publication Date |
2012-06-12 |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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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 |
90 |
Open Access |
|
Notes |
Fwo; Iap; Iwt |
Approved |
Most recent IF: 12.124; 2012 IF: 10.015 |
Call Number |
UA @ lucian @ c:irua:100340 |
Serial |
183 |
Permanent link to this record |
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Author |
Colla, M.-S.; Amin-Ahmadi, B.; Idrissi, H.; Malet, L.; Godet, S.; Raskin, J.-P.; Schryvers, D.; Pardoen, T. |
Title |
Dislocation-mediated relaxation in nanograined columnar palladium films revealed by on-chip time-resolved HRTEM testing |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
6 |
Issue |
6 |
Pages |
5922 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The high-rate sensitivity of nanostructured metallic materials demonstrated in the recent literature is related to the predominance of thermally activated deformation mechanisms favoured by a large density of internal interfaces. Here we report time-resolved high-resolution electron transmission microscopy creep tests on thin nanograined films using on-chip nanomechanical testing. Tests are performed on palladium, which exhibited unexpectedly large creep rates at room temperature. Despite the small 30-nm grain size, relaxation is found to be mediated by dislocation mechanisms. The dislocations interact with the growth nanotwins present in the grains, leading to a loss of coherency of twin boundaries. The density of stored dislocations first increases with applied deformation, and then decreases with time to drive additional deformation while no grain boundary mechanism is observed. This fast relaxation constitutes a key issue in the development of various micro- and nanotechnologies such as palladium membranes for hydrogen applications. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000348742300002 |
Publication Date |
2015-01-05 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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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 |
34 |
Open Access |
|
Notes |
Iap7/21; Fwo G012012n |
Approved |
Most recent IF: 12.124; 2015 IF: 11.470 |
Call Number |
c:irua:122045 |
Serial |
731 |
Permanent link to this record |
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|
Author |
Dubrovinsky, L.; Dubrovinskaia, N.; Prakapenka, V.B.; Abakumov, A.M. |
Title |
Implementation of micro-ball nanodiamond anvils for high-pressure studies above 6 Mbar |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
3 |
Issue |
|
Pages |
1163-1167 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Since invention of the diamond anvil cell technique in the late 1950s for studying materials at extreme conditions, the maximum static pressure generated so far at room temperature was reported to be about 400 GPa. Here we show that use of micro-semi-balls made of nanodiamond as second-stage anvils in conventional diamond anvil cells drastically extends the achievable pressure range in static compression experiments to above 600 GPa. Micro-anvils (10-50 mu m in diameter) of superhard nano-diamond (with a grain size below similar to 50 nm) were synthesized in a large volume press using a newly developed technique. In our pilot experiments on rhenium and gold we have studied the equation of state of rhenium at pressures up to 640 GPa and demonstrated the feasibility and crucial necessity of the in situ ultra high-pressure measurements for accurate determination of material properties at extreme conditions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000313514100073 |
Publication Date |
2012-10-23 |
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 |
150 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 12.124; 2012 IF: 10.015 |
Call Number |
UA @ lucian @ c:irua:110134 |
Serial |
1563 |
Permanent link to this record |
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|
Author |
Li, J.; Ji, M.; Schwarz, T.; Ke, X.; Van Tendeloo, G.; Yuan, J.; Pereira, P.J.; Huang, Y.; Zhang, G.; Feng, H.L.; Yuan, Y.H.; Hatano, T.; Kleiner, R.; Koelle, D.; Chibotaru, L.F.; Yamaura, K.; Wang, H.B.; Wu, P.H.; Takayama-Muromachi, E.; Vanacken, J.; Moshchalkov, V.V.; |
Title |
Local destruction of superconductivity by non-magnetic impurities in mesoscopic iron-based superconductors |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
6 |
Issue |
6 |
Pages |
7614 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The determination of the pairing symmetry is one of the most crucial issues for the iron-based superconductors, for which various scenarios are discussed controversially. Non-magnetic impurity substitution is one of the most promising approaches to address the issue, because the pair-breaking mechanism from the non-magnetic impurities should be different for various models. Previous substitution experiments demonstrated that the non-magnetic zinc can suppress the superconductivity of various iron-based superconductors. Here we demonstrate the local destruction of superconductivity by non-magnetic zinc impurities in Ba0.5K0.5Fe2As2 by exploring phase-slip phenomena in a mesoscopic structure with 119 × 102 nm2 cross-section. The impurities suppress superconductivity in a three-dimensional Swiss cheese-like pattern with in-plane and out-of-plane characteristic lengths slightly below ~1.34 nm. This causes the superconducting order parameter to vary along abundant narrow channels with effective cross-section of a few square nanometres. The local destruction of superconductivity can be related to Cooper pair breaking by non-magnetic impurities. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000358857000007 |
Publication Date |
2015-07-03 |
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 |
12 |
Open Access |
|
Notes |
246791 Countatoms |
Approved |
Most recent IF: 12.124; 2015 IF: 11.470 |
Call Number |
c:irua:126677 |
Serial |
1827 |
Permanent link to this record |
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|
Author |
Tongay, S.; Sahin, H.; Ko, C.; Luce, A.; Fan, W.; Liu, K.; Zhou, J.; Huang, Y.S.; Ho, C.H.; Yan, J.; Ogletree, D.F.; Aloni, S.; Ji, J.; Li, S.; Li, J.; Peeters, F.M.; Wu, J.; |
Title |
Monolayer behaviour in bulk ReS2 due to electronic and vibrational decoupling |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
5 |
Issue |
|
Pages |
3252 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Semiconducting transition metal dichalcogenides consist of monolayers held together by weak forces where the layers are electronically and vibrationally coupled. Isolated monolayers show changes in electronic structure and lattice vibration energies, including a transition from indirect to direct bandgap. Here we present a new member of the family, rhenium disulphide (ReS2), where such variation is absent and bulk behaves as electronically and vibrationally decoupled monolayers stacked together. From bulk to monolayers, ReS2 remains direct bandgap and its Raman spectrum shows no dependence on the number of layers. Interlayer decoupling is further demonstrated by the insensitivity of the optical absorption and Raman spectrum to interlayer distance modulated by hydrostatic pressure. Theoretical calculations attribute the decoupling to Peierls distortion of the 1T structure of ReS2, which prevents ordered stacking and minimizes the interlayer overlap of wavefunctions. Such vanishing interlayer coupling enables probing of two-dimensional-like systems without the need for monolayers. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
|
Wos |
000332666700010 |
Publication Date |
2014-02-06 |
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 |
12.124 |
Times cited |
806 |
Open Access |
|
Notes |
; This work was supported by the United States Department of Energy Early Career Award DE-FG02-11ER46796. The high pressure part of this work was supported by COMPRES, the Consortium for Materials Properties Research in Earth Sciences, under National Science Foundation Cooperative Agreement EAR 11-577758. The electron microscopy and nano-Auger measurements were supported by the user programme at the Molecular Foundry, which was supported by the Office of Science, Office of Basic Energy Sciences, of the United States Department of Energy under contract no. DE-AC02-05CH11231. S. A. gratefully acknowledges Dr Virginia Altoe of the Molecular Foundry for help with the TEM data acquisition and analysis. J.L. acknowledges support from the Natural Science Foundation of China for Distinguished Young Scholar (grant nos. 60925016 and 91233120). Y.-S.H. and C.-H. H. acknowledge support from the National Science Council of Taiwan under project nos. NSC 100-2112-M-011-001-MY3 and NSC 101-2221-E-011-052-MY3. H. S. was supported by the FWO Pegasus Marie Curie Long Fellowship programme. The DFT work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem programme of the Flemish government. Computational resources were partially provided by TUBITAK ULAKBIM, High Performance and Grid Computing Centre. ; |
Approved |
Most recent IF: 12.124; 2014 IF: 11.470 |
Call Number |
UA @ lucian @ c:irua:119247 |
Serial |
2192 |
Permanent link to this record |
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|
Author |
Zhang, J.; Ke, X.; Gou, G.; Seidel, J.; Xiang, B.; Yu, P.; Liang, W.I.; Minor, A.M.; Chu, Y.h.; Van Tendeloo, G.; Ren, X.; Ramesh, R.; |
Title |
A nanoscale shape memory oxide |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
4 |
Issue |
|
Pages |
2768-8 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Stimulus-responsive shape-memory materials have attracted tremendous research interests recently, with much effort focused on improving their mechanical actuation. Driven by the needs of nanoelectromechanical devices, materials with large mechanical strain, particularly at nanoscale level, are therefore desired. Here we report on the discovery of a large shape-memory effect in bismuth ferrite at the nanoscale. A maximum strain of up to ~14% and a large volumetric work density of ~600±90 J cm−3 can be achieved in association with a martensitic-like phase transformation. With a single step, control of the phase transformation by thermal activation or electric field has been reversibly achieved without the assistance of external recovery stress. Although aspects such as hysteresis, microcracking and so on have to be taken into consideration for real devices, the large shape-memory effect in this oxide surpasses most alloys and, therefore, demonstrates itself as an extraordinary material for potential use in state-of-art nanosystems. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000328023900006 |
Publication Date |
2013-11-19 |
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 |
67 |
Open Access |
|
Notes |
Countatoms |
Approved |
Most recent IF: 12.124; 2013 IF: 10.742 |
Call Number |
UA @ lucian @ c:irua:111431 |
Serial |
2271 |
Permanent link to this record |
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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 |
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. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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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 |
Permanent link to this record |
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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 |
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 |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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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 |
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|
Author |
Zhang, B.; Dugas, R.; Rousse, G.; Rozier, P.; Abakumov, A.M.; Tarascon, J.-M. |
Title |
Insertion compounds and composites made by ball milling for advanced sodium-ion batteries |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
7 |
Issue |
7 |
Pages |
10308 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Sodium-ion batteries have been considered as potential candidates for stationary energy storage because of the low cost and wide availability of Na sources. However, their future commercialization depends critically on control over the solid electrolyte interface formation, as well as the degree of sodiation at the positive electrode. Here we report an easily scalable ball milling approach, which relies on the use of metallic sodium, to prepare a variety of sodium-based alloys, insertion layered oxides and polyanionic compounds having sodium in excess such as the Na4V2(PO4)(2)F-3 phase. The practical benefits of preparing sodium-enriched positive electrodes as reservoirs to compensate for sodium loss during solid electrolyte interphase formation are demonstrated by assembling full C/P'2-Na-1[Fe0.5Mn0.5]O-2 and C/'Na3+xV2(PO4)(2)F-3' sodium-ion cells that show substantial increases (>10%) in energy storage density. Our findings may offer electrode design principles for accelerating the development of the sodium-ion technology. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
|
Language |
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Wos |
000369021400002 |
Publication Date |
2016-01-18 |
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 |
104 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 12.124 |
Call Number |
UA @ lucian @ c:irua:131599 |
Serial |
4197 |
Permanent link to this record |
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|
Author |
Mefford, J.T.; Rong, X.; Abakumov, A.M.; Hardin, W.G.; Dai, S.; Kolpak, A.M.; Johnston, K.P.; Stevenson, K.J. |
Title |
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 |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000372721700001 |
Publication Date |
2016-03-23 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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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 |
Permanent link to this record |
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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 |
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 |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000397799700001 |
Publication Date |
2017-03-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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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 |
Permanent link to this record |
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Author |
Guzzinati, G.; Béché, A.; Lourenço-Martins, H.; Martin, J.; Kociak, M.; Verbeeck, J. |
Title |
Probing the symmetry of the potential of localized surface plasmon resonances with phase-shaped electron beams |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
8 |
Issue |
8 |
Pages |
14999 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Plasmonics, the science and technology of the interaction of light with metallic objects, is fundamentally changing the way we can detect, generate and manipulate light. Although the field is progressing swiftly, thanks to the availability of nanoscale manufacturing and analysis methods, fundamental properties such as the plasmonic excitations’ symmetries cannot be accessed directly, leading to a partial, sometimes incorrect, understanding of their properties. Here we overcome this limitation by deliberately shaping the wave function of an electron beam to match a plasmonic excitations’ symmetry in a modified transmission electron microscope. We show experimentally and theoretically that this offers selective detection of specific plasmon modes within metallic nanoparticles, while excluding modes with other symmetries. This method resembles the widespread use of polarized light for the selective excitation of plasmon modes with the advantage of locally probing the response of individual plasmonic objects and a far wider range of symmetry selection criteria. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000399084300001 |
Publication Date |
2017-04-12 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
84 |
Open Access |
OpenAccess |
Notes |
; We thank F.J. Garcia de Abajo and D.M. Ugarte for interesting and fruitful discussion. This work was supported by funding from the European Research Council under the 7th Framework Program (FP7) ERC Starting Grant 278510 VORTEX. Financial support from the European Union under the Framework 7 program under a contract for an Integrated Infrastructure Initiative (Reference number 312483 ESTEEM2) is also gratefully acknowledged. Aluminum nanostructures were fabricated using the Nanomat nanofabrication facility. ; |
Approved |
Most recent IF: 12.124 |
Call Number |
EMAT @ emat @ c:irua:142205UA @ admin @ c:irua:142205 |
Serial |
4548 |
Permanent link to this record |
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Author |
Ghorbanfekr-Kalashami, H.; Vasu, K.S.; Nair, R.R.; Peeters, F.M.; Neek-Amal, M. |
Title |
Dependence of the shape of graphene nanobubbles on trapped substance |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
8 |
Issue |
8 |
Pages |
15844 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Van der Waals (vdW) interaction between two-dimensional crystals (2D) can trap substances in high pressurized (of order 1 GPa) on nanobubbles. Increasing the adhesion between the 2D crystals further enhances the pressure and can lead to a phase transition of the trapped material. We found that the shape of the nanobubble can depend critically on the properties of the trapped substance. In the absence of any residual strain in the top 2D crystal, flat nanobubbles can be formed by trapped long hydrocarbons (that is, hexadecane). For large nanobubbles with radius 130 nm, our atomic force microscopy measurements show nanobubbles filled with hydrocarbons (water) have a cylindrical symmetry (asymmetric) shape which is in good agreement with our molecular dynamics simulations. This study provides insights into the effects of the specific material and the vdW pressure on the microscopic details of graphene bubbles. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000403417500001 |
Publication Date |
2017-06-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
44 |
Open Access |
|
Notes |
We acknowledge fruitful discussion with Irina Grigorieva and Andre K. Geim. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program, the Royal Society and the Engineering and Physical Sciences Research Council, UK (EP/K016946/1). M.N.-A. was supported by Iran National Science Foundation (INSF). |
Approved |
Most recent IF: 12.124 |
Call Number |
CMT @ cmt @ c:irua:144189 |
Serial |
4580 |
Permanent link to this record |
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Author |
Chirayath, V.A.; Callewaert, V.; Fairchild, A.J.; Chrysler, M.D.; Gladen, R.W.; Mcdonald, A.D.; Imam, S.K.; Shastry, K.; Koymen, A.R.; Saniz, R.; Barbiellini, B.; Rajeshwar, K.; Partoens, B.; Weiss, A.H. |
Title |
Auger electron emission initiated by the creation of valence-band holes in graphene by positron annihilation |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
8 |
Issue |
8 |
Pages |
16116 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Auger processes involving the filling of holes in the valence band are thought to make important contributions to the low-energy photoelectron and secondary electron spectrum from many solids. However, measurements of the energy spectrum and the efficiency with which electrons are emitted in this process remain elusive due to a large unrelated background resulting from primary beam-induced secondary electrons. Here, we report the direct measurement of the energy spectra of electrons emitted from single layer graphene as a result of the decay of deep holes in the valence band. These measurements were made possible by eliminating competing backgrounds by employing low-energy positrons (<1.25 eV) to create valence-band holes by annihilation. Our experimental results, supported by theoretical calculations, indicate that between 80 and 100% of the deep valence-band holes in graphene are filled via an Auger transition. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000405398200001 |
Publication Date |
2017-07-13 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
20 |
Open Access |
|
Notes |
The experiments in this work were supported by the grant NSF DMR 1508719. A.H.W and A.R.K. gratefully acknowledge support for the building of advanced positron beam through the grant NSF DMR MRI 1338130. V.C. and R.S. were supported by the FWO-Vlaanderen through Project No. G. 0224.14N. The computational resources and services used in this work were in part provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the Hercules Foundation and the Flemish Government (EWI Department). 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. |
Approved |
Most recent IF: 12.124 |
Call Number |
CMT @ cmt @ c:irua:144625 |
Serial |
4627 |
Permanent link to this record |
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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 |
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 |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000385444300004 |
Publication Date |
2016-09-22 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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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 |
Permanent link to this record |
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Author |
Embon, L.; Anahory, Y.; Jelić, Z.L.; Lachman, E.O.; Myasoedov, Y.; Huber, M.E.; Mikitik, G.P.; Silhanek, A.V.; Milošević, M.V.; Gurevich, A.; Zeldov, E. |
Title |
Imaging of super-fast dynamics and flow instabilities of superconducting vortices |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
8 |
Issue |
|
Pages |
85 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Quantized magnetic vortices driven by electric current determine key electromagnetic properties of superconductors. While the dynamic behavior of slow vortices has been thoroughly investigated, the physics of ultrafast vortices under strong currents remains largely unexplored. Here, we use a nanoscale scanning superconducting quantum interference device to image vortices penetrating into a superconducting Pb film at rates of tens of GHz and moving with velocities of up to tens of km/s, which are not only much larger than the speed of sound but also exceed the pair-breaking speed limit of superconducting condensate. These experiments reveal formation of mesoscopic vortex channels which undergo cascades of bifurcations as the current and magnetic field increase. Our numerical simulations predict metamorphosis of fast Abrikosov vortices into mixed Abrikosov-Josephson vortices at even higher velocities. This work offers an insight into the fundamental physics of dynamic vortex states of superconductors at high current densities, crucial for many applications. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000405900400002 |
Publication Date |
2017-07-13 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
124 |
Open Access |
|
Notes |
; We would like to thank M.L. Rappaport for fruitful discussions and technical support. This work was supported by the US-Israel Binational Science Foundation (BSF) grant No. 2014155 and the Israel Science Foundation grant No. 132/14. A.G. was also supported by the United States Department of Energy under Grant No. DE-SC0010081. M.V.M. acknowledges support from Research Foundation-Flanders (FWO). The work of Z.L.J. and A.V.S. was partially supported by “Mandat d'Impulsion Scientifique” MIS F.4527.13 of the F.R.S.-FNRS. This work benefited from the support of COST action MP-1201. ; |
Approved |
Most recent IF: 12.124 |
Call Number |
UA @ lucian @ c:irua:144832 |
Serial |
4720 |
Permanent link to this record |
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Author |
Li, J.; Pereira, P.J.; Yuan, J.; Lv, Y.-Y.; Jiang, M.-P.; Lu, D.; Lin, Z.-Q.; Liu, Y.-J.; Wang, J.-F.; Li, L.; Ke, X.; Van Tendeloo, G.; Li, M.-Y.; Feng, H.-L.; Hatano, T.; Wang, H.-B.; Wu, P.-H.; Yamaura, K.; Takayama-Muromachi, E.; Vanacken, J.; Chibotaru, L.F.; Moshchalkov, V.V. |
Title |
Nematic superconducting state in iron pnictide superconductors |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
8 |
Issue |
1 |
Pages |
1880 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Nematic order often breaks the tetragonal symmetry of iron-based superconductors. It arises from regular structural transition or electronic instability in the normal phase. Here, we report the observation of a nematic superconducting state, by measuring the angular dependence of the in-plane and out-of-plane magnetoresistivity of Ba 0.5 K 0.5 Fe 2 As 2 single crystals. We find large twofold oscillations in the vicinity of the superconducting transition, when the direction of applied magnetic field is rotated within the basal plane. To avoid the influences from sample geometry or current flow direction, the sample was designed as Corbino-shape for in-plane and mesa-shape for out-of-plane measurements. Theoretical analysis shows that the nematic superconductivity arises from the weak mixture of the quasi-degenerate s-wave and d-wave components of the superconducting condensate, most probably induced by a weak anisotropy of stresses inherent to single crystals. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000416933400002 |
Publication Date |
2017-11-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
8 |
Open Access |
OpenAccess |
Notes |
The authors J.L., P.J.P., and J.Y. contributed equally to this work. J.L. and J.Y. designed the experiments. J.L., H.-L.F., K.Y., and E.T.-M. grew the single crystals. J.L., J.Y., Y.-Y.L., M.-P.J., D.L., M.-Y.L., T.H., H.-B.W., P.-H.W., K.Y., E.T.-M., J.V., and V.V.M. fabricated the devices and measured transport properties. J.L., Y.-Y.L., Z.-Q.L., Y.-J.L., J.-F.W., and L.L. studied on the pulsed high field measurements. X.K. and G.V.T. measured the low temperature TEM. All authors discussed the data. J.L., P.J.P., and L.F.C. proposed the model and simulated the results. J.L., P.J.P., K.Y., E.T.-M., and L.F.C. analyzed the data and prepared the manuscript. |
Approved |
Most recent IF: 12.124 |
Call Number |
EMAT @ emat @c:irua:147348 |
Serial |
4772 |
Permanent link to this record |
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Author |
Dendooven, J.; Ramachandran, R.K.; Solano, E.; Kurttepeli, M.; Geerts, L.; Heremans, G.; Ronge, J.; Minjauw, M.M.; Dobbelaere, T.; Devloo-Casier, K.; Martens, J.A.; Vantomme, A.; Bals, S.; Portale, G.; Coati, A.; Detavernier, C. |
Title |
Independent tuning of size and coverage of supported Pt nanoparticles using atomic layer deposition |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
8 |
Issue |
8 |
Pages |
1074 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Synthetic methods that allow for the controlled design of well-defined Pt nanoparticles are highly desirable for fundamental catalysis research. In this work, we propose a strategy that allows precise and independent control of the Pt particle size and coverage. Our approach exploits the versatility of the atomic layer deposition (ALD) technique by combining two ALD processes for Pt using different reactants. The particle areal density is controlled by tailoring the number of ALD cycles using trimethyl(methylcyclopentadienyl) platinum and oxygen, while subsequent growth using the same Pt precursor in combination with nitrogen plasma allows for tuning of the particle size at the atomic level. The excellent control over the particle morphology is clearly demonstrated by means of in situ and ex situ X-ray fluorescence and grazing incidence small angle X-ray scattering experiments, providing information about the Pt loading, average particle dimensions, and mean center-to-center particle distance. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000413353500023 |
Publication Date |
2017-10-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
88 |
Open Access |
OpenAccess |
Notes |
; This research was funded by the Research Foundation-Flanders (FWO), the Special Research Fund BOF of Ghent University (GOA 01G01513) and the Flemish Government (Medium-scale research infrastructure funding-Hercules funding). J. D., T. D. and M. M. M. acknowledge the FWO for a research fellowship. S. B. acknowledges the European Research Council, ERC grant no. 335078-Colouratom. For the GISAXS and XRF measurements at SOLEIL, the authors received funding from the European Community's Trans National Access Program CALIPSO. We are also grateful to the SOLEIL and ESRF staff for smoothly running the facilities. The authors thank G. Verellen for his help with drawing the 3D sketches. ; ecas_Sara |
Approved |
Most recent IF: 12.124 |
Call Number |
UA @ lucian @ c:irua:146668UA @ admin @ c:irua:146668 |
Serial |
4786 |
Permanent link to this record |
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Author |
Becker, M.; Guzzinati, G.; Béché, A.; Verbeeck, J.; Batelaan, H. |
Title |
Asymmetry and non-dispersivity in the Aharonov-Bohm effect |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Nature communications |
Abbreviated Journal |
Nat Commun |
Volume |
10 |
Issue |
10 |
Pages |
1700 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Decades ago, Aharonov and Bohm showed that electrons are affected by electromagnetic potentials in the absence of forces due to fields. Zeilinger's theorem describes this absence of classical force in quantum terms as the “dispersionless” nature of the Aharonov-Bohm effect. Shelankov predicted the presence of a quantum “force” for the same Aharonov-Bohm physical system as elucidated by Berry. Here, we report an experiment designed to test Shelankov's prediction and we provide a theoretical analysis that is intended to elucidate the relation between Shelankov's prediction and Zeilinger's theorem. The experiment consists of the Aharonov-Bohm physical system; free electrons pass a magnetized nanorod and far-field electron diffraction is observed. The diffraction pattern is asymmetric confirming one of Shelankov's predictions and giving indirect experimental evidence for the presence of a quantum “force”. Our theoretical analysis shows that Zeilinger's theorem and Shelankov's result are both special cases of one theorem. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000464338100011 |
Publication Date |
2019-04-12 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
12 |
Open Access |
OpenAccess |
Notes |
; H.B. would like to thank Michael Berry for bringing the presence of a quantum “force” to our attention. A.B., G.G. and J.V. acknowledge support from the European Research Council under the 7th Framework Program (FP7) ERC Starting Grant 278510 VORTEX. G.G. acknowledges support from the Fonds Wetenschappelijk Onderzoek -Vlaanderen (FWO). M.B. and H.B. acknowledge support by the U.S. National Science Foundation under Grant No. 1602755. ; |
Approved |
Most recent IF: 12.124 |
Call Number |
UA @ admin @ c:irua:159341 |
Serial |
5241 |
Permanent link to this record |