| |
Records |
Links |
|
Author |
Samal, D.; Tan, H.; Takamura, Y.; Siemons, W.; Verbeeck, J.; Van Tendeloo, G.; Arenholz, E.; Jenkins, C.A.; Rijnders, G.; Koster, G. |
|
| |
Title |
Direct structural and spectroscopic investigation of ultrathin films of tetragonal CuO: Six-fold coordinated copper |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
Europhysics letters |
Abbreviated Journal |
Epl-Europhys Lett |
|
| |
Volume |
105 |
Issue |
1 |
Pages |
17003-17005 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract  |
Unlike other 3d transition metal monoxides (MnO, FeO, CoO, and NiO), CuO is found in a low-symmetry distorted monoclinic structure rather than the rocksalt structure. We report here of the growth of ultrathin CuO films on SrTiO3 substrates; scanning transmission electron microscopy was used to show the stabilization of a tetragonal rocksalt structure with an elongated c-axis such that c/a similar to 1.34 and the Cu-O-Cu bond angle similar to 180 degrees, pointing to metastable six-fold coordinated Cu. X-ray absorption spectroscopy demonstrates that the hole at the Cu site for the CuO is localized in 3d(x2-y2) orbital unlike the well-studied monoclinic CuO phase. The experimental confirmation of the tetragonal structure of CuO opens up new avenues to explore electronic and magnetic properties of six-fold coordinated Cu. Copyright (C) EPLA, 2014 |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
Paris |
Editor |
|
|
| |
Language |
|
Wos |
000331197100015 |
Publication Date |
2014-01-30 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0295-5075;1286-4854; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
1.957 |
Times cited |
15 |
Open Access |
|
|
| |
Notes |
This work was carried out with financial support from the AFOSR and EOARD projects (project No.: FA8655-10-1-3077) and also supported by funding from the European Research Council under the 7th Framework Program (FP7), ERC grant No. 246791 – COUNTATOMS, ERC Starting Grant 278510 VORTEX, Grant No. NMP3-LA-2010-246102 IFOX and an Integrated Infrastructure Initiative, reference No. 312483-ESTEEM2. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. Advanced Light Source is supported by the Office of Science, Office of Basic Energy Sciences of the U.S. Department of Energy (DOE) under Contract No. DE-AC02-05CH11231. YT acknowledges support from the National Science Foundation (DMR-0747896). WS was supported by the US DOE, Basic Energy Sciences, Materials Sciences and Engineering Division. ECASJO_; |
Approved |
Most recent IF: 1.957; 2014 IF: 2.095 |
|
| |
Call Number |
UA @ lucian @ c:irua:115806UA @ admin @ c:irua:115806 |
Serial |
722 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Tran Phong Le, P.; Hofhuis, K.; Rana, A.; Huijben, M.; Hilgenkamp, H.; Rijnders, G.A.J.H.M.; ten Elshof, J.E.; Koster, G.; Gauquelin, N.; Lumbeeck, G.; Schuessler-Langeheine, C.; Popescu, H.; Fortuna, F.; Smit, S.; Verbeek, X.H.; Araizi-Kanoutas, G.; Mishra, S.; Vaskivskyi, I.; Duerr, H.A.; Golden, M.S. |
|
| |
Title |
Tailoring vanadium dioxide film orientation using nanosheets : a combined microscopy, diffraction, transport, and soft X-ray in transmission study |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Advanced Functional Materials |
Abbreviated Journal |
Adv Funct Mater |
|
| |
Volume |
30 |
Issue |
1 |
Pages |
1900028 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Vanadium dioxide (VO2) is a much-discussed material for oxide electronics and neuromorphic computing applications. Here, heteroepitaxy of VO2 is realized on top of oxide nanosheets that cover either the amorphous silicon dioxide surfaces of Si substrates or X-ray transparent silicon nitride membranes. The out-of-plane orientation of the VO2 thin films is controlled at will between (011)(M1)/(110)(R) and (-402)(M1)/(002)(R) by coating the bulk substrates with Ti0.87O2 and NbWO6 nanosheets, respectively, prior to VO2 growth. Temperature-dependent X-ray diffraction and automated crystal orientation mapping in microprobe transmission electron microscope mode (ACOM-TEM) characterize the high phase purity, the crystallographic and orientational properties of the VO2 films. Transport measurements and soft X-ray absorption in transmission are used to probe the VO2 metal-insulator transition, showing results of a quality equal to those from epitaxial films on bulk single-crystal substrates. Successful local manipulation of two different VO2 orientations on a single substrate is demonstrated using VO2 grown on lithographically patterned lines of Ti0.87O2 and NbWO6 nanosheets investigated by electron backscatter diffraction. Finally, the excellent suitability of these nanosheet-templated VO2 films for advanced lensless imaging of the metal-insulator transition using coherent soft X-rays is discussed. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000505545800010 |
Publication Date |
2019-10-31 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1616-301x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
19 |
Times cited |
1 |
Open Access |
OpenAccess |
|
| |
Notes |
P.T.P.L. and K.H. contributed equally to this work. The authors thank Mark A. Smithers for performing high-resolution scanning electron microscopy and electron backscattering diffraction. The authors also thank Dr. Nicolas Jaouen for his contribution to the soft X-ray imaging experiments. This work is part of the DESCO research program of the Foundation for Fundamental Research on Matter (FOM), which is part of the Netherlands Organisation for Scientific Research (NWO). P.T.P.L. acknowledges the NWO/CW ECHO grant ECHO.15.CM2.043. N.G. acknowledges funding from the Geconcentreerde Onderzoekacties (GOA) project “Solarpaint” of the University of Antwerp and the FLAG-ERA JTC 2017 project GRAPH-EYE. G.L. acknowledges financial support from the Flemish Research Fund (FWO) under project G.0365.15N. I.V. acknowledges support by the U.S. Department of Energy, Office of Science under Award Number 0000231415. |
Approved |
Most recent IF: 19; 2020 IF: 12.124 |
|
| |
Call Number |
UA @ admin @ c:irua:165705 |
Serial |
6325 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Birkholzer, Y.A.; Sotthewes, K.; Gauquelin, N.; Riekehr, L.; Jannis, D.; van der Minne, E.; Bu, Y.; Verbeeck, J.; Zandvliet, H.J.W.; Koster, G.; Rijnders, G. |
|
| |
Title |
High-strain-induced local modification of the electronic properties of VO₂ thin films |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
ACS applied electronic materials |
Abbreviated Journal |
|
|
| |
Volume |
4 |
Issue |
12 |
Pages |
6020-6028 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
Vanadium dioxide (VO2) is a popular candidate for electronic and optical switching applications due to its well-known semiconductor-metal transition. Its study is notoriously challenging due to the interplay of long- and short-range elastic distortions, as well as the symmetry change and the electronic structure changes. The inherent coupling of lattice and electronic degrees of freedom opens the avenue toward mechanical actuation of single domains. In this work, we show that we can manipulate and monitor the reversible semiconductor-to-metal transition of VO2 while applying a controlled amount of mechanical pressure by a nanosized metallic probe using an atomic force microscope. At a critical pressure, we can reversibly actuate the phase transition with a large modulation of the conductivity. Direct tunneling through the VO2-metal contact is observed as the main charge carrier injection mechanism before and after the phase transition of VO2. The tunneling barrier is formed by a very thin but persistently insulating surface layer of the VO2. The necessary pressure to induce the transition decreases with temperature. In addition, we measured the phase coexistence line in a hitherto unexplored regime. Our study provides valuable information on pressure-induced electronic modifications of the VO2 properties, as well as on nanoscale metal-oxide contacts, which can help in the future design of oxide electronics. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000890974900001 |
Publication Date |
2022-11-18 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2637-6113 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
| |
Impact Factor |
|
Times cited |
2 |
Open Access |
OpenAccess |
|
| |
Notes |
This work received financial support from the project Green ICT (grant number 400.17.607) of the research program NWA, which is financed by the Dutch Research Council (NWO), Research Foundation Flanders (FWO grant number G0F1320N), and the European Union’s Horizon 2020 research and innovation program within a contract for Integrating Activities for Advanced Communities (grant number 823717 − ESTEEM3). The K2 camera was funded through the Research Foundation Flanders (FWO-Hercules grant number G0H4316N – “Direct electron detector for soft matter TEM”).; esteem3reported; esteem3jra |
Approved |
Most recent IF: NA |
|
| |
Call Number |
UA @ admin @ c:irua:192712 |
Serial |
7309 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Araizi-Kanoutas, G.; Geessinck, J.; Gauquelin, N.; Smit, S.; Verbeek, X.H.; Mishra, S.K.; Bencok, P.; Schlueter, C.; Lee, T.-L.; Krishnan, D.; Fatermans, J.; Verbeeck, J.; Rijnders, G.; Koster, G.; Golden, M.S. |
|
| |
Title |
Co valence transformation in isopolar LaCoO3/LaTiO3 perovskite heterostructures via interfacial engineering |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Physical review materials |
Abbreviated Journal |
Phys. Rev. Materials |
|
| |
Volume |
4 |
Issue |
2 |
Pages |
026001 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
We report charge transfer up to a single electron per interfacial unit cell across nonpolar heterointerfaces from the Mott insulator LaTiO3 to the charge transfer insulator LaCoO3. In high-quality bi- and trilayer systems grown using pulsed laser deposition, soft x-ray absorption, dichroism, and scanning transmission electron microscopy-electron energy loss spectroscopy are used to probe the cobalt-3d electron count and provide an element-specific investigation of the magnetic properties. The experiments show the cobalt valence conversion is active within 3 unit cells of the heterointerface, and able to generate full conversion to 3d7 divalent Co, which displays a paramagnetic ground state. The number of LaTiO3/LaCoO3 interfaces, the thickness of an additional, electronically insulating “break” layer between the LaTiO3 and LaCoO3, and the LaCoO3 film thickness itself in trilayers provide a trio of control knobs for average charge of the cobalt ions in LaCoO3, illustrating the efficacy of O−2p band alignment as a guiding principle for property design in complex oxide heterointerfaces. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Wos |
000513551200007 |
Publication Date |
2020-02-10 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
2475-9953 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.4 |
Times cited |
13 |
Open Access |
OpenAccess |
|
| |
Notes |
Nederlandse Organisatie voor Wetenschappelijk Onderzoek; Universiteit Antwerpen; Horizon 2020, 730872 ; Department of Science and Technology, Ministry of Science and Technology, SR/NM/Z-07/2015 ; Jawaharlal Nehru Centre for Advanced Scientific Research; |
Approved |
Most recent IF: 3.4; 2020 IF: NA |
|
| |
Call Number |
EMAT @ emat @c:irua:167787 |
Serial |
6376 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Koster, G.; Verbist, K.; Rijnders, G.; Rogalla, H.; Van Tendeloo, G.; Blank, D.H.A. |
|
| |
Title |
Structure and properties of (Sr,Ca)CuO2-BaCuO2 superlattices grown by pulsed laser interval deposition |
Type |
A1 Journal article |
| |
Year |
2001 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
|
| |
Volume |
353 |
Issue |
3-4 |
Pages |
167-183 |
|
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
| |
Abstract |
We report on the preparation of CuBa(2)(Sr(x)Ca(1-x))(n)Cu(n-1)O(y) compounds by fabrication of (Ba,Sr,Ca)CuO(2) superlattices with pulsed laser deposition (PLD). A technique called interval deposition is used to suppress multi-level or island growth resulting in high-quality superlattice structures. Both, the applicability of PLD to atomic engineering as well as the fabrication of artificial superconductors is demonstrated. The (Sr,Ca)CuO(2)-BaCuO(2) superlattices are characterized by X-ray diffraction, high-resolution electron microscopy (HREM) and selected area electron diffraction. The superlattice period has been deduced from electron diffraction patterns and XRD measurements. For Sr containing films, the best growth behavior is observed and films with the highest degree of crystallinity are obtained, whereas superconductivity is only found in less crystalline, Ca containing films. Under some deposition conditions and depending on the amount of Ba containing layers in the superlattice, it was observed that the BaCuO(2) material is converted to Ba(2)CuO(4-delta). Image simulations to interpret the HREM contrast are performed. (C) 2001 Elsevier Science B.V. All rights reserved. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
|
| |
Language |
|
Wos |
000168861100003 |
Publication Date |
2002-07-25 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
1.404 |
Times cited |
8 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 1.404; 2001 IF: 0.806 |
|
| |
Call Number |
UA @ lucian @ c:irua:103417 |
Serial |
3293 |
|
| Permanent link to this record |
