|
Records |
|
Author |
Kang, J.; Sahin, H.; Peeters, F.M. |
|
Title |
Tuning carrier confinement in the MoS2/WS2 lateral heterostructure |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
|
Volume |
119 |
Issue |
119 |
Pages |
9580-9586 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
|
Abstract |
To determine and control the spatial confinement of charge carriers is of importance for nanoscale optoelectronic device applications. Using first-principles calculations, we investigate the tunability of band alignment and Charge localization in lateral and combined lateral vertical heterostructures of MoS2 and WS2. First, we Show that a type-II to type-I band alignment transition takes place when tensile strain is applied on the WS2 region. This band alignment transition is a result of the different response of the band edge states with strain and is caused by their different wave function characters. Then we show that the presence of the grain boundary introduces localized in-gap states. The boundary at the armchair interface significantly modifies the charge distribution of the valence band maximum (VBM) state, whereas in a heterostructure with tilt grain domains both conducation band maximum (CBM) and VBM are found to be localized around the grain boundary. We also found that the thickness of the constituents in a lateral heterostructure also determines how the electrons and holes are confined. Creating combined lateral vertical heterostructures of MOS2/WS2 provides another way cif tuning the charge confinement. These results provide possible ways to tune the carrier confinement in MoS2/WS2 heterostructures, which are interesting for its practical: applications in the future. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
|
Language |
|
Wos |
000353930700066 |
Publication Date |
2015-04-07 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
4.536 |
Times cited |
73 |
Open Access |
|
|
Notes |
; This work was supported by the Methusalem program of the Flemish government. H.S. is supported by a FWO Pegasus Marie Curie-long Fellowship and J.K. by a FWO Pegasus Marie Curie-short Fellowship. ; |
Approved |
Most recent IF: 4.536; 2015 IF: 4.772 |
|
Call Number |
c:irua:126381 |
Serial |
3747 |
Permanent link to this record |
|
|
|
|
Author |
Kang, J.; Sahin, H.; Peeters, F.M. |
|
Title |
Mechanical properties of monolayer sulphides : a comparative study between MoS2, HfS2 and TiS3 |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
|
Volume |
17 |
Issue |
17 |
Pages |
27742-27749 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
The in-plane stiffness (C), Poisson's ratio (nu), Young's modulus and ultimate strength (sigma) along two different crystallographic orientations are calculated for the single layer crystals: MoS2, HfS2 and TiS3 in 1H, 1T and monoclinic phases. We find that MoS2 and HfS2 have isotropic in-plane stiffnesses of 124.24 N m(-1) and 79.86 N m(-1), respectively. While for TiS3 the in-plane stiffness is highly anisotropic due to its monoclinic structure, with C-x = 83.33 N m(-1) and C-y = 133.56 N m(-1) (x and y are parallel to its longer and shorter in-plane lattice vectors.). HfS2 which is in the 1T phase has the smallest anisotropy in its ultimate strength, whereas TiS3 in the monoclinic phase has the largest. Along the armchair direction MoS2 has the largest sigma of 23.48 GPa, whereas along y TiS3 has the largest sigma of 18.32 GPa. We have further analyzed the band gap response of these materials under uniaxial tensile strain, and find that they exhibit different behavior. Along both armchair and zigzag directions, the band gap of MoS2 (HfS2) decreases (increases) as strain increases, and the response is almost isotropic. For TiS3, the band gap decreases when strain is along x, while if strain is along y, the band gap increases first and then decreases beyond a threshold strain value. The different characteristics observed in these sulphides with different structures shed light on the relationship between the structure and properties, which is useful for applications in nanotechnology. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
|
Language |
|
Wos |
000363193800055 |
Publication Date |
2015-09-25 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1463-9076 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
4.123 |
Times cited |
83 |
Open Access |
|
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Super-computer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus-Long Marie Curie Fellowship, and J.K. by a FWO Pegasus-Short Marie Curie Fellowship. ; |
Approved |
Most recent IF: 4.123; 2015 IF: 4.493 |
|
Call Number |
UA @ lucian @ c:irua:129478 |
Serial |
4204 |
Permanent link to this record |
|
|
|
|
Author |
Kang, T.-Y.; Kwon, J.-S.; Kumar, N.; Choi, E.; Kim, K.-M. |
|
Title |
Effects of a Non-Thermal Atmospheric Pressure Plasma Jet with Different Gas Sources and Modes of Treatment on the Fate of Human Mesenchymal Stem Cells |
Type |
A1 Journal article |
|
Year |
2019 |
Publication |
Applied Sciences |
Abbreviated Journal |
Appl Sci-Basel |
|
Volume |
9 |
Issue |
22 |
Pages |
4819 |
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
Abstract |
Despite numerous attempts to use human mesenchymal stem cells (hMSCs) in the field of tissue engineering, the control of their differentiation remains challenging. Here, we investigated possible applications of a non-thermal atmospheric pressure plasma jet (NTAPPJ) to control the differentiation of hMSCs. An air- or nitrogen-based NTAPPJ was applied to hMSCs in culture media, either directly or by media treatment in which the cells were plated after the medium was exposed to the NTAPPJ. The durations of exposure were 1, 2, and 4 min, and the control was not exposed to the NTAPPJ. The initial attachment of the cells was assessed by a water-soluble tetrazolium assay, and the gene expression in the cells was assessed through reverse-transcription polymerase chain reaction and immunofluorescence staining. The results showed that the gene expression in the hMSCs was generally increased by the NTAPPJ exposure, but the enhancement was dependent on the conditions of the exposure, such as the source of the gas and the treatment method used. These results were attributed to the chemicals in the extracellular environment and the reactive oxygen species generated by the plasma. Hence, it was concluded that by applying the best conditions for the NTAPPJ exposure of hMSCs, the control of hMSC differentiation was possible, and therefore, exposure to an NTAPPJ is a promising method for tissue engineering. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000502570800096 |
Publication Date |
2019-11-11 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
2076-3417 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
1.679 |
Times cited |
|
Open Access |
|
|
Notes |
The plasma source was kindly provided by the Plasma Bioscience Research Center, Kwangwoon University. |
Approved |
Most recent IF: 1.679 |
|
Call Number |
PLASMANT @ plasmant @c:irua:164893 |
Serial |
5435 |
Permanent link to this record |
|
|
|
|
Author |
Kante, M.V.; Weber, M.L.; Ni, S.; van den Bosch, I.C.G.; van der Minne, E.; Heymann, L.; Falling, L.J.; Gauquelin, N.; Tsvetanova, M.; Cunha, D.M.; Koster, G.; Gunkel, F.; Nemsak, S.; Hahn, H.; Estrada, L.V.; Baeumer, C. |
|
Title |
A high-entropy oxide as high-activity electrocatalyst for water oxidation |
Type |
A1 Journal article |
|
Year |
2023 |
Publication |
ACS nano |
Abbreviated Journal |
|
|
Volume |
17 |
Issue |
6 |
Pages |
5329-5339 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
High-entropy materials are an emerging pathway in the development of high-activity (electro)catalysts because of the inherent tunability and coexistence of multiple potential active sites, which may lead to earth-abundant catalyst materials for energy-efficient electrochemical energy storage. In this report, we identify how the multication composition in high-entropy perovskite oxides (HEO) contributes to high catalytic activity for the oxygen evolution reaction (OER), i.e., the key kinetically limiting half-reaction in several electrochemical energy conversion technologies, including green hydrogen generation. We compare the activity of the (001) facet of LaCr0.2Mn0.2Fe0.2Co0.2Ni0.2O3-delta with the parent compounds (single B-site in the ABO3 perovskite). While the single B-site perovskites roughly follow the expected volcano-type activity trends, the HEO clearly outperforms all of its parent compounds with 17 to 680 times higher currents at a fixed overpotential. As all samples were grown as an epitaxial layer, our results indicate an intrinsic composition-function relationship, avoiding the effects of complex geometries or unknown surface composition. In-depth X-ray photoemission studies reveal a synergistic effect of simultaneous oxidation and reduction of different transition metal cations during the adsorption of reaction intermediates. The surprisingly high OER activity demonstrates that HEOs are a highly attractive, earth-abundant material class for high-activity OER electrocatalysts, possibly allowing the activity to be fine-tuned beyond the scaling limits of mono-or bimetallic oxides. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000953440900001 |
Publication Date |
2023-03-13 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1936-0851 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
17.1 |
Times cited |
|
Open Access |
OpenAccess |
|
Notes |
|
Approved |
Most recent IF: 17.1; 2023 IF: 13.942 |
|
Call Number |
UA @ admin @ c:irua:196097 |
Serial |
7390 |
Permanent link to this record |
|
|
|
|
Author |
Kao, K.-H.; Verhulst, A.S.; Van de Put, M.; Vandenberghe, W.G.; Sorée, B.; Magnus, W.; De Meyer, K. |
|
Title |
Tensile strained Ge tunnel field-effect transistors: k\cdot p material modeling and numerical device simulation |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
|
Volume |
115 |
Issue |
4 |
Pages |
044505-44508 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
Group IV based tunnel field-effect transistors generally show lower on-current than III-V based devices because of the weaker phonon-assisted tunneling transitions in the group IV indirect bandgap materials. Direct tunneling in Ge, however, can be enhanced by strain engineering. In this work, we use a 30-band k.p method to calculate the band structure of biaxial tensile strained Ge and then extract the bandgaps and effective masses at Gamma and L symmetry points in k-space, from which the parameters for the direct and indirect band-to-band tunneling (BTBT) models are determined. While transitions from the heavy and light hole valence bands to the conduction band edge at the L point are always bridged by phonon scattering, we highlight a new finding that only the light-holelike valence band is strongly coupling to the conduction band at the Gamma point even in the presence of strain based on the 30-band k.p analysis. By utilizing a Technology Computer Aided Design simulator equipped with the calculated band-to-band tunneling BTBT models, the electrical characteristics of tensile strained Ge point and line tunneling devices are self-consistently computed considering multiple dynamic nonlocal tunnel paths. The influence of field-induced quantum confinement on the tunneling onset is included. Our simulation predicts that an on-current up to 160 (260) mu A/mu m can be achieved along with on/off ratio > 10(6) for V-DD = 0.5V by the n-type (p-type) line tunneling device made of 2.5% biaxial tensile strained Ge. (C) 2014 AIP Publishing LLC. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
|
Language |
|
Wos |
000331210800113 |
Publication Date |
2014-01-26 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0021-8979;1089-7550; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.068 |
Times cited |
26 |
Open Access |
|
|
Notes |
; Authors would like to thank Dr. Mohammad Ali Pourghaderi for useful discussions on the nonparabolicity. Authors would also like to thank Professor Eddy Simoen and Dr. Yosuke Shimura for useful discussions about the validity of modeled bandgaps and effective masses. This work was also supported by IMEC's Industrial Affiliation Program. ; |
Approved |
Most recent IF: 2.068; 2014 IF: 2.183 |
|
Call Number |
UA @ lucian @ c:irua:115800 |
Serial |
3505 |
Permanent link to this record |
|
|
|
|
Author |
Kao, K.-H.; Verhulst, A.S.; Vandenberghe, W.G.; Sorée, B.; Groeseneken, G.; De Meyer, K. |
|
Title |
Direct and indirect band-to-band tunneling in germanium-based TFETs |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
IEEE transactions on electron devices |
Abbreviated Journal |
Ieee T Electron Dev |
|
Volume |
59 |
Issue |
2 |
Pages |
292-301 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
Germanium is a widely used material for tunnel FETs because of its small band gap and compatibility with silicon. Typically, only the indirect band gap of Ge at 0.66 eV is considered. However, direct band-to-band tunneling (BTBT) in Ge should be included in tunnel FET modeling and simulations since the energy difference between the Ge conduction band edges at the L and G valleys is only 0.14 eV at room temperature. In this paper, we theoretically calculate the parameters A and B of Kane's direct and indirect BTBT models at different tunneling directions ([100], [110], and [111]) for Si, Ge and unstrained Si1-xGex. We highlight how the direct BTBT component becomes more important as the Ge mole fraction increases. The calculation of the band-to-band generation rate in the uniform electric field limit reveals that direct tunneling always dominates over indirect tunneling in Ge. The impact of the direct transition in Ge on the performance of two realistic tunnel field-effect transistor configurations is illustrated with TCAD simulations. The influence of field-induced quantum confinement is included in the analysis based on a back-of-the-envelope calculation. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
|
Language |
|
Wos |
000299430200005 |
Publication Date |
2011-12-07 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0018-9383;1557-9646; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.605 |
Times cited |
212 |
Open Access |
|
|
Notes |
; Manuscript received August 5, 2011; revised October 5, 2011 and October 28, 2011; accepted October 30, 2011. Date of publication December 7, 2011; date of current version January 25, 2012. This work was supported by the Interuniversity Microelectronics Center's (IMEC) Industrial Affiliation Program. The work of W. G. Vandenberghe was supported by a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). The review of this paper was arranged by Editor A. Schenk. ; |
Approved |
Most recent IF: 2.605; 2012 IF: 2.062 |
|
Call Number |
UA @ lucian @ c:irua:97215 |
Serial |
708 |
Permanent link to this record |
|
|
|
|
Author |
Kao, K.-H.; Verhulst, A.S.; Vandenberghe, W.G.; Sorée, B.; Groeseneken, G.; De Meyer, K. |
|
Title |
Modeling the impact of junction angles in tunnel field-effect transistors |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
Solid state electronics |
Abbreviated Journal |
Solid State Electron |
|
Volume |
69 |
Issue |
|
Pages |
31-37 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
We develop an analytical model for a tunnel field-effect transistor (TFET) with a tilted source junction angle. The tunnel current is derived by using circular tunnel paths along the electric field. The analytical model predicts that a smaller junction angle improves the TFET performance, which is supported by device simulations. An analysis is also made based on straight tunnel paths and tunnel paths corresponding to the trajectory of a classical particle. In all the aforementioned cases, the same conclusions are obtained. A TFET configuration with an encroaching polygon source junction is studied to analyze the junction angle dependence at the smallest junction angles. The improvement of the subthreshold swing (SS) with decreasing junction angle can be achieved by using thinner effective oxide thickness, smaller band gap material and longer encroaching length of the encroaching junction. A TFET with a smaller junction angle on the source side also has an innate immunity against the degradation of the fringing field from the gate electrode via a high-k spacer. A large junction angle on the drain side can suppress the unwanted ambipolar current of TFETs. (c) 2011 Elsevier Ltd. All rights reserved. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
|
Language |
|
Wos |
000301561600009 |
Publication Date |
2012-01-16 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0038-1101; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
1.58 |
Times cited |
9 |
Open Access |
|
|
Notes |
; We acknowledge the input on nanowire processing of Rita Rooyackers and useful discussions with Wim Magnus. William Vandenberghe gratefully acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). This work was also supported by imec's Industrial Affiliation Program. ; |
Approved |
Most recent IF: 1.58; 2012 IF: 1.482 |
|
Call Number |
UA @ lucian @ c:irua:97816 |
Serial |
2145 |
Permanent link to this record |
|
|
|
|
Author |
Kao, K.-H.; Verhulst, A.S.; Vandenberghe, W.G.; Sorée, B.; Magnus, W.; Leonelli, D.; Groeseneken, G.; De Meyer, K. |
|
Title |
Optimization of gate-on-source-only tunnel FETs with counter-doped pockets |
Type |
A1 Journal article |
|
Year |
2012 |
Publication |
IEEE transactions on electron devices |
Abbreviated Journal |
Ieee T Electron Dev |
|
Volume |
59 |
Issue |
8 |
Pages |
2070-2077 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
We investigate a promising tunnel FET configuration having a gate on the source only, which is simultaneously exhibiting a steeper subthreshold slope and a higher ON-current than the lateral tunneling configuration with a gate on the channel. Our analysis is performed based on a recently developed 2-D quantum-mechanical simulator calculating band-to-band tunneling and including quantum confinement (QC). It is shown that the two disadvantages of the structure, namely, the sensitivity to gate alignment and the physical oxide thickness, are mitigated by placing a counter-doped parallel pocket underneath the gate-source overlap. The pocket also significantly reduces the field-induced QC. The findings are illustrated with all-Si and all-Ge gate-on-source-only tunnel field-effect transistor simulations. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
|
Language |
|
Wos |
000306920200011 |
Publication Date |
2012-06-27 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0018-9383;1557-9646; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.605 |
Times cited |
72 |
Open Access |
|
|
Notes |
; Manuscript received February 17, 2012; revised May 7, 2012; accepted May 11, 2012. Date of publication June 26, 2012; date of current version July 19, 2012. This work was supported by the Interuniversity Microelectronics Center's Industrial Affiliation Program. The work of W. G. Vandenberghe was supported by the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen) through a Ph.D. stipend. The review of this paper was arranged by Editor H. S. Momose. ; |
Approved |
Most recent IF: 2.605; 2012 IF: 2.062 |
|
Call Number |
UA @ lucian @ c:irua:100820 |
Serial |
2487 |
Permanent link to this record |
|
|
|
|
Author |
Kapra, A. |
|
Title |
Controlling the flux dynamics in superconductors by nanostructured magnetic arrays |
Type |
Doctoral thesis |
|
Year |
2013 |
Publication |
|
Abbreviated Journal |
|
|
Volume |
|
Issue |
|
Pages |
|
|
Keywords |
Doctoral thesis; Condensed Matter Theory (CMT) |
|
Abstract |
|
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Antwerpen |
Editor |
|
|
Language |
|
Wos |
|
Publication Date |
0000-00-00 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record |
|
Impact Factor |
|
Times cited |
|
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: NA |
|
Call Number |
UA @ lucian @ c:irua:114596 |
Serial |
508 |
Permanent link to this record |
|
|
|
|
Author |
Kapra, A.V.; Misko, V.R.; Peeters, F.M. |
|
Title |
Controlling magnetic flux motion by arrays of zigzag-arranged magnetic bars |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
|
Volume |
26 |
Issue |
2 |
Pages |
025011-10 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
Recent advances in manufacturing arrays of artificial pinning sites, i.e., antidots, blind holes and magnetic dots, allowed an effective control of magnetic flux in superconductors. An array of magnetic bars deposited on top of a superconducting film was shown to display different pinning regimes depending on the direction of the in-plane magnetization of the bars. Changing the sign of their magnetization results in changes in the induced magnetic pinning potentials. By numerically solving the time-dependent Ginzburg-Landau equations in a superconducting film with periodic arrays of zigzag-arranged magnetic bars, we revealed various flux dynamics regimes. In particular, we demonstrate flux pinning and flux flow, depending on the direction of the magnetization of the magnetic bars. Remarkably, the revealed different flux-motion regimes are associated with different mechanisms of vortex-antivortex dynamics. For example, we found that for an 'antiparallel' configuration of magnetic bars this dynamics involves a repeating vortex-antivortex generation and annihilation. We show that the depinning transition and the onset of flux flow can be manipulated by the magnetization of the bars and the geometry of the array. This provides an effective control of the depinning critical current that can be useful for possible fluxonics applications. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
|
Language |
|
Wos |
000313559300011 |
Publication Date |
2012-12-20 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0953-2048;1361-6668; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.878 |
Times cited |
5 |
Open Access |
|
|
Notes |
; We acknowledge useful discussions with Denis Vodolazov and Alejandro Silhanek. This work was supported by the 'Odysseus' Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 2.878; 2013 IF: 2.796 |
|
Call Number |
UA @ lucian @ c:irua:110080 |
Serial |
505 |
Permanent link to this record |
|
|
|
|
Author |
Kapra, A.V.; Misko, V.R.; Vodolazov, D.Y.; Peeters, F.M. |
|
Title |
The guidance of vortex-antivortex pairs by in-plane magnetic dipoles in a superconducting finite-size film |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
|
Volume |
24 |
Issue |
2 |
Pages |
024014-024014,8 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
The possibility of manipulating vortex matter by using various artificial pinning arrays is of significant importance for possible applications in nano and micro fluxonics devices. By numerically solving the time-dependent GinzburgLandau equations, we study the vortexantivortex (vav) dynamics in a hybrid structure consisting of a finite-size superconductor with magnetic dipoles on top which generate vav pairs in the presence of an external current. The vav dynamics is analyzed for different arrangements and magnetic moments of the dipoles, as a function of angle α between the direction of the magnetic dipole and that of the Lorentz force produced by the applied current. The interplay of the attractive interaction between a vav pair and the Lorentz force leads either to the separation of (anti)vortices and their motion in opposite directions or to their annihilation. We found a critical angle αc, below which vortices and antivortices are repelled, while for larger angles they annihilate. In case of a single (few) magnetic dipole(s), this magnetic dipole induced vav guidance is influenced by the self-interaction of the vav pairs with their images in a finite-size sample, while for a periodic array of dipoles the guidance is determined by the interaction of a vav pair with other dipoles and vav pairs created by them. This effect is tunable through the external current and the magnetization and size of the magnetic dipoles. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
|
Language |
|
Wos |
000286379900015 |
Publication Date |
2011-01-20 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0953-2048;1361-6668; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.878 |
Times cited |
28 |
Open Access |
|
|
Notes |
; This work was supported by the 'Odysseus' program of the Flemish Government and the Flemish Science Foundation (FWO-Vl), the Interuniversity Attraction Poles (IAP) Programme-Belgian State-Belgian Science Policy, and the FWO-Vl. DYV acknowledges support from the Russian Fund for Basic Research and Russian Agency of Education under the Federal Programme 'Scientific and educational personnel of innovative Russia in 2009-2013'. ; |
Approved |
Most recent IF: 2.878; 2011 IF: 2.662 |
|
Call Number |
UA @ lucian @ c:irua:88732 |
Serial |
1399 |
Permanent link to this record |
|
|
|
|
Author |
Kapra, A.V.; Vodolazov, D.Y.; Misko, V.R. |
|
Title |
Vortex transport in a channel with periodic constrictions |
Type |
A1 Journal article |
|
Year |
2013 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
|
Volume |
26 |
Issue |
9 |
Pages |
095010-95011 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
By numerically solving the time-dependent Ginzburg-Landau equations in a type-II superconductor, characterized by a critical temperature T-c1, and the coherence length xi(1), with a channel formed by overlapping rhombuses (diamond-like channel) made of another type-II superconductor, characterized, in general, by different T-c2 and xi(2), we investigate the dynamics of driven vortex matter for varying parameters of the channel: the width of the neck connecting the diamond cells, the cell geometry, and the ratio between the coherence lengths in the bank and the channel. We analyzed samples with periodic boundary conditions (which we call 'infinite' samples) and finite-size samples (with boundaries for vortex entry/exit), and we found that by tuning the channel parameters, one can manipulate the vortex dynamics, e.g., change the transition from flux-pinned to flux-flow regime and tune the slope of the IV-curves. In addition, we analyzed the effect of interstitial vortices on these characteristics. The critical current of this device was studied as a function of the applied magnetic field, j(c)(H). The function j(c)(H) reveals a striking commensurability peak, in agreement with recent experimental observations. The obtained results suggest that the diamond channel, which combines the properties of pinning arrays and flux-guiding channels, can be a promising candidate for potential use in devices controlling magnetic flux motion. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
|
Language |
|
Wos |
000323073800016 |
Publication Date |
2013-07-30 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0953-2048;1361-6668; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.878 |
Times cited |
2 |
Open Access |
|
|
Notes |
; This work was supported by the 'Odysseus' Program of the Flemish Government and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 2.878; 2013 IF: 2.796 |
|
Call Number |
UA @ lucian @ c:irua:110737 |
Serial |
3898 |
Permanent link to this record |
|
|
|
|
Author |
Kara De Maeijer, P.; Craeye, B.; Snellings, R.; Kazemi-Kamyab, H.; Loots, M.; Janssens, K.; Nuyts, G. |
|
Title |
Effect of ultra-fine fly ash on concrete performance and durability |
Type |
A1 Journal article |
|
Year |
2020 |
Publication |
Construction And Building Materials |
Abbreviated Journal |
Constr Build Mater |
|
Volume |
263 |
Issue |
|
Pages |
120493-13 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Energy and Materials in Infrastructure and Buildings (EMIB) |
|
Abstract |
In the present study ultra-fine fly ash as a novel by-product obtained by a dry and closed separation process was investigated as cement replacement in concrete. The impact of ultra-fine fly ash on material properties was investigated following an upscaling as an approach considering paste, mortar and concrete properties. Two types of cement, Portland cement (CEMI) and slag cement (CEMIII), two types of ultra-fly ashes, one with particle size d90< 9.3lm (FA1) and second with d90< 4.6lm (FA2) were used.At paste- and mortar- level, cement was replaced at 0%, 15%, 25%, 35% and 50% with FA1 and FA2. At concrete- level, cement was replaced at 0%, 15% and 25% with different ratios of FA1 and FA2. The results at paste- and mortar- level showed that an increased fineness of the fly ash (FA2) contributes to better workability of the mix. For CEMI, the compressive strength of concrete with FA2 at 25% cement replacement was already equal to the reference 0% replacement concrete at the age of 28 days. For CEMIII, the compressive strength of concrete mix with FA1 with 15% and FA2 with 25% cement replacements reached the reference concrete value at the age of 91 days. Regarding the durability, replacing cement with ultra-fine fly ash (FA2) had a positive influence on the resistivity, chloride migration coefficient and alkali-silica reaction (ASR), and a negative influence on the carbonation resistance. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000582567100093 |
Publication Date |
2020-10-13 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0950-0618 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
7.4 |
Times cited |
|
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 7.4; 2020 IF: 3.169 |
|
Call Number |
UA @ admin @ c:irua:171815 |
Serial |
6498 |
Permanent link to this record |
|
|
|
|
Author |
Karaaslan, Y.; Haskins, J.B.; Yapicioglu, H.; Sevik, C. |
|
Title |
Influence of randomly distributed vacancy defects on thermal transport in two-dimensional group-III nitrides |
Type |
A1 Journal article |
|
Year |
2021 |
Publication |
Journal Of Applied Physics |
Abbreviated Journal |
J Appl Phys |
|
Volume |
129 |
Issue |
22 |
Pages |
224304 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
Efficient thermal transport control is a fundamental issue for electronic device applications such as information, communication, and energy storage technologies in modern electronics in order to achieve desired thermal conditions. Structural defects in materials provide a mechanism to adjust the thermal transport properties of these materials on demand. In this context, the effect of structural defects on lattice thermal conductivities of two-dimensional hexagonal binary group-III nitride (XN, X = B, Al, and Ga) semiconductors is systematically investigated by means of classical molecular dynamics simulations performed with recently developed transferable inter-atomic potentials accurately describing defect energies. Here, two different Green-Kubo based approaches and another approach based on non-equilibrium molecular dynamics are compared in order to get an overall understanding. Our investigation clearly shows that defect concentrations of 3% decrease the thermal conductivity of systems containing these nitrites up to 95%. Results hint that structural defects can be used as effective adjustment parameters in controlling thermal transport properties in device applications associated with these materials. Published under an exclusive license by AIP Publishing. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000692024300001 |
Publication Date |
2021-06-09 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.068 |
Times cited |
|
Open Access |
Not_Open_Access |
|
Notes |
|
Approved |
Most recent IF: 2.068 |
|
Call Number |
UA @ admin @ c:irua:181618 |
Serial |
8096 |
Permanent link to this record |
|
|
|
|
Author |
Karaaslan, Y.; Yapicioglu, H.; Sevik, C. |
|
Title |
Assessment of Thermal Transport Properties of Group-III Nitrides: A Classical Molecular Dynamics Study with Transferable Tersoff-Type Interatomic Potentials |
Type |
A1 Journal article |
|
Year |
2020 |
Publication |
Physical Review Applied |
Abbreviated Journal |
Phys Rev Appl |
|
Volume |
13 |
Issue |
3 |
Pages |
034027 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
In this study, by means of classical molecular dynamics simulations, we investigate the thermal-transport properties of hexagonal single-layer, zinc-blend, and wurtzite phases of BN, AlN, and GaN crystals, which are very promising for the application and design of high-quality electronic devices. With this in mind, we generate fully transferable Tersoff-type empirical interatomic potential parameter sets by utilizing an optimization procedure based on particle-swarm optimization. The predicted thermal properties as well as the structural, mechanical, and vibrational properties of all materials are in very good agreement with existing experimental and first-principles data. The impact of isotopes on thermal transport is also investigated and between approximately 10 and 50% reduction in phonon thermal transport with random isotope distribution is observed in BN and GaN crystals. Our investigation distinctly shows that the generated parameter sets are fully transferable and very useful in exploring the thermal properties of systems containing these nitrides. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000518820200003 |
Publication Date |
2020-03-10 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
2331-7019 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
4.6 |
Times cited |
|
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 4.6; 2020 IF: 4.808 |
|
Call Number |
UA @ admin @ c:irua:193766 |
Serial |
7508 |
Permanent link to this record |
|
|
|
|
Author |
Karabidak, S.M.; Čevik, U.; Kaya, S. |
|
Title |
A new method to compensate for counting losses due to system dead time |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Nuclear instruments and methods in physics research : A: accelerators, spectrometers, detectors and associated equipment |
Abbreviated Journal |
|
|
Volume |
603 |
Issue |
3 |
Pages |
361-364 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
Abstract |
Determination of count losses and pile-up pulse effects in quantitative and qualitative analysis became a vital step in various analyses. Therefore, compensating for counting losses is of importance. These counting losses are due to the pulse pile-up, paralyzable and non-paralyzable system dead time or a combination of these mechanisms. In this work, a new method is suggested for the correction of dead time losses resulting from the above mechanisms. For this purpose, a source code was developed. It was found that the peaking time was an important parameter over system dead time. The method suggested seems to be more effective even at high count rate. (C) 2009 Elsevier B.V. All rights reserved. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000266829400021 |
Publication Date |
2009-02-14 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0168-9002 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
|
Times cited |
|
Open Access |
|
|
Notes |
|
Approved |
no |
|
Call Number |
UA @ admin @ c:irua:94550 |
Serial |
8304 |
Permanent link to this record |
|
|
|
|
Author |
Karakulina, O. |
|
Title |
Quantitative electron diffraction tomography for structure characterization of cathode materials for Li-ion batteries |
Type |
Doctoral thesis |
|
Year |
2018 |
Publication |
|
Abbreviated Journal |
|
|
Volume |
|
Issue |
|
Pages |
|
|
Keywords |
Doctoral thesis; Electron microscopy for materials research (EMAT) |
|
Abstract |
|
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Antwerpen |
Editor |
|
|
Language |
|
Wos |
|
Publication Date |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record |
|
Impact Factor |
|
Times cited |
|
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: NA |
|
Call Number |
UA @ lucian @ c:irua:151805 |
Serial |
5039 |
Permanent link to this record |
|
|
|
|
Author |
Karakulina, O.M.; Demortière, A.; Dachraoui, W.; Abakumov, A.M.; Hadermann, J. |
|
Title |
In Situ Electron Diffraction Tomography Using a Liquid-Electrochemical Transmission Electron Microscopy Cell for Crystal Structure Determination of Cathode Materials for Li-Ion batteries |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
|
Volume |
18 |
Issue |
10 |
Pages |
6286-6291 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
We demonstrate that changes in the unit cell structure of lithium battery cathode materials during electrochemical cycling in liquid electrolyte can be determined for particles of just a few hundred nanometers in size using in situ transmission electron microscopy (TEM). The atomic coordinates, site occupancies (including lithium occupancy), and cell parameters of the materials can all be reliably quantified. This was achieved using electron diffraction tomography (EDT) in a sealed electrochemical cell with conventional liquid electrolyte (LP30) and LiFePO4 crystals, which have a well-documented charged structure to use as reference. In situ EDT in a liquid environment cell provides a viable alternative to in situ X-ray and neutron diffraction experiments due to the more local character of TEM, allowing for single crystal diffraction data to be obtained from multiphased powder samples and from submicrometer- to nanometer-sized particles. EDT is the first in situ TEM technique to provide information at the unit cell level in the liquid environment of a commercial TEM electrochemical cell. Its application to a wide range of electrochemical experiments in liquid environment cells and diverse types of crystalline materials can be envisaged. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000447355400024 |
Publication Date |
2018-10-10 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1530-6984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
12.712 |
Times cited |
12 |
Open Access |
Not_Open_Access: Available from 08.09.2019
|
|
Notes |
O.M. Karakulina, A.M. Abakumov and J. Hadermann acknowledge support from FWO under grant G040116N. A. Demortière wants to thank the French network on the electrochemical energy storage (RS2E), the Store-Ex Labex, for the financial support. Finally, the Fonds Européen de Développement Régional (FEDER), CNRS, Région Hauts-de-France, and Ministère de l’Education Nationale de l’Enseignement Supérieur et de la Recherche are acknowledged for funding. |
Approved |
Most recent IF: 12.712 |
|
Call Number |
EMAT @ emat @c:irua:154750 |
Serial |
5063 |
Permanent link to this record |
|
|
|
|
Author |
Karakulina, O.M.; Khasanova, N.R.; Drozhzhin, O.A.; Tsirlin, A.A.; Hadermann, J.; Antipov, E.V.; Abakumov, A.M. |
|
Title |
Antisite Disorder and Bond Valence Compensation in Li2FePO4F Cathode for Li-Ion Batteries |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Chemistry Of Materials |
Abbreviated Journal |
Chem Mater |
|
Volume |
28 |
Issue |
28 |
Pages |
7578-7581 |
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
|
Abstract |
|
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000387518500004 |
Publication Date |
2016-11-08 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
9.466 |
Times cited |
10 |
Open Access |
|
|
Notes |
Russian Science Foundation, 16-19-00190 ; Fonds Wetenschappelijk Onderzoek, G040116N ; |
Approved |
Most recent IF: 9.466 |
|
Call Number |
EMAT @ emat @ c:irua:139170 c:irua:138599 |
Serial |
4320 |
Permanent link to this record |
|
|
|
|
Author |
Karapetrov, G.; Belkin, A.; Iavarone, M.; Fedor, J.; Novosad, V.; Milošević, M.V.; Peeters, F.M. |
|
Title |
Anisotropic superconductivity and vortex dynamics in magnetically coupled F/S and F/S/F hybrids |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Journal of superconductivity and novel magnetism |
Abbreviated Journal |
J Supercond Nov Magn |
|
Volume |
24 |
Issue |
1/2 |
Pages |
905-910 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
Magnetically coupled superconductorferromagnet hybrids offer advanced routes for nanoscale control of superconductivity. Magnetotransport characteristics and scanning tunneling microscopy images of vortex structures in superconductorferromagnet hybrids reveal rich superconducting phase diagrams. Focusing on a particular combination of a ferromagnet with a well-ordered periodic magnetic domain structure with alternating out-of-plane component of magnetization, and a small coherence length superconductor, we find directed nucleation of superconductivity above the domain wall boundaries. We show that near the superconductor-normal state phase boundary the superconductivity is localized in narrow mesoscopic channels. In order to explore the Abrikosov flux line ordering in F/S hybrids, we use a combination of scanning tunneling microscopy and GinzburgLandau simulations. The magnetic stripe domain structure induces periodic local magnetic induction in the superconductor, creating a series of pinninganti-pinning channels for externally added magnetic flux quanta. Such laterally confined Abrikosov vortices form quasi-1D arrays (chains). The transitions between multichain states occur through propagation of kinks at the intermediate fields. At high fields we show that the system becomes nonlinear due to a change in both the number of vortices and the confining potential. In F/S/F hybrids we demonstrate the evolution of the anisotropic conductivity in the superconductor that is magnetically coupled with two adjacent ferromagnetic layers. Stripe magnetic domain structures in both F-layers are aligned under each other, resulting in a directional superconducting order parameter in the superconducting layer. The conductance anisotropy strongly depends on the period of the magnetic domains and the strength of the local magnetization. The anisotropic conductivity of up to three orders of magnitude can be achieved with a spatial critical temperature modulation of 5% of T c. Induced anisotropic properties in the F/S and F/S/F hybrids have a potential for future application in switching and nonvolatile memory elements operating at low temperatures. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
|
Language |
|
Wos |
000289855700150 |
Publication Date |
2010-10-01 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1557-1939;1557-1947; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
1.18 |
Times cited |
2 |
Open Access |
|
|
Notes |
; This work as well as the use of the Center for Nanoscale Materials and the Electron Microscopy Center at Argonne National Laboratory were supported by UChicago Argonne, LLC, Operator of Argonne National Laboratory (“Argonne”). Argonne, a U.S. Department of Energy Office of Science laboratory, is operated under Contract No. DE-AC02-06CH11357. This work was also supported by the Ministry of Education, Agency for Structural Funds of the European Union, Research and Development Program, under agreement 262 401 200 19. M.V.M. and F. M. P. acknowledge support from the Flemish Science Foundation (FWO-VI), the Belgian Science Policy, the JSPS/ESF-NES program, the ESF-AQDJJ network, and the Vlaanderen-USA bilateral program. ; |
Approved |
Most recent IF: 1.18; 2011 IF: 0.650 |
|
Call Number |
UA @ lucian @ c:irua:89930 |
Serial |
130 |
Permanent link to this record |
|
|
|
|
Author |
Karapetrov, G.; Milošević, M.V.; Iavarone, M.; Fedor, J.; Belkin, A.; Novosad, V.; Peeters, F.M. |
|
Title |
Transverse instabilities of multiple vortex chains in magnetically coupled NbSe2/permalloy superconductor/ferromagnet bilayers |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
|
Volume |
80 |
Issue |
18 |
Pages |
180506,1-180506,4 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
Using scanning tunneling microscopy and Ginzburg-Landau simulations, we explore vortex configurations in magnetically coupled NbSe2/permalloy superconductor/ferromagnet bilayer. The permalloy film with stripe domain structure induces periodic local magnetic induction in the superconductor, creating a series of pinning-antipinning channels for externally added magnetic flux quanta. Such laterally confined Abrikosov vortices form quasi-one-dimensional arrays (chains). The transitions between multichain states occur through propagation of kinks at the intermediate fields. At high fields we show that the system becomes nonlinear due to a change in both the number of vortices and the confining potential. The longitudinal instabilities of the resulting vortex structures lead to vortices levitating in the antipinning channels. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
|
Language |
|
Wos |
000272310900031 |
Publication Date |
2009-11-18 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
3.836 |
Times cited |
38 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
|
Call Number |
UA @ lucian @ c:irua:80314 |
Serial |
3729 |
Permanent link to this record |
|
|
|
|
Author |
Karavolas, V.C.; Triberis, G.P.; Peeters, F.M. |
|
Title |
Electrical and thermal transport of composite fermions |
Type |
A1 Journal article |
|
Year |
1997 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
Volume |
56 |
Issue |
|
Pages |
15289-15298 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
|
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
|
Language |
|
Wos |
000071043700067 |
Publication Date |
2002-07-27 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0163-1829;1095-3795; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
3.836 |
Times cited |
11 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 3.836; 1997 IF: NA |
|
Call Number |
UA @ lucian @ c:irua:19272 |
Serial |
891 |
Permanent link to this record |
|
|
|
|
Author |
Karczewski, G.; Wojtowicz, T.; Wang, Y.-J.; Wu, X.; Peeters, F.M. |
|
Title |
Electron effective mass and resonant polaron effect in CdTe/CdMgTe quantum wells |
Type |
A1 Journal article |
|
Year |
2002 |
Publication |
Physica status solidi: B: basic research
T2 – 10th International Conference on II-VI Compounds, SEP 09-14, 2001, BREMEN, GERMANY |
Abbreviated Journal |
Phys Status Solidi B |
|
Volume |
229 |
Issue |
1 |
Pages |
597-600 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
Cyclotron resonance in CdTe/CdMgTe quantum wells (QWs) was studied. Due to the polaron effect the zero-field effective mass is strongly influenced by the QW width. The experimental data have been described theoretically by taking into account electron-phonon coupling and the nonparabolicity of the conduction band. The subband structure was calculated self-consistently. The best fit was obtained for an electron-phonon coupling constant alpha = 0.3 and bare electron mass of m(b) = 0.092m(0). |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
Berlin |
Editor |
|
|
Language |
|
Wos |
000173806600118 |
Publication Date |
2002-08-25 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0370-1972;1521-3951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
1.674 |
Times cited |
10 |
Open Access |
|
|
Notes |
|
Approved |
Most recent IF: 1.674; 2002 IF: 0.930 |
|
Call Number |
UA @ lucian @ c:irua:102838 |
Serial |
925 |
Permanent link to this record |
|
|
|
|
Author |
Kardel, F.; Wuyts, K.; De Wael, K.; Samson, R. |
|
Title |
Biomonitoring of atmospheric particulate pollution via chemical composition and magnetic properties of roadside tree leaves |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
Environmental Science and Pollution Research |
Abbreviated Journal |
Environ Sci Pollut R |
|
Volume |
25 |
Issue |
26 |
Pages |
25994-26004 |
|
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
Abstract |
Particulate matter (PM) is a main atmospheric pollution which threats human health and well-being. In this research, we chemically and magnetically analysed roadside tree leaves, collected from three tree species in two main roads (from two different cities) and a reference area, for 28 elements and the saturation isothermal remanent magnetisation. Comparison of unwashed and washed leaves revealed that deposited particles on the leaf surface contain various elements including Al, Ca, Fe, Mg, Mn, Na, Si, Ti, Ba, Co, Cr, Cu, Ni, Rb, V, Zn and Zr. Moreover, there was no significant difference between washed/unwashed leaves in Cl, K, P, S, As, Cd, Cs, Pb, Sn and Sr concentrations, which indicates tree leaves may not be a suitable biomonitor for these elements. Our results showed that site and tree species are important factors which affect atmospheric elements deposition. Among the three considered tree species, Chamaecyparis lawsoniana showed the highest potential for atmospheric particle accumulation. The PCA results revealed that Al, Fe, Ti, Co, Cr, Cu, Ni, Rb, Si, V, Zn and Zr indicated emissions from road traffic activities and soil dust; Ca, Mg and Na from sea salts and Mn and Sb from industrial activity. The biplot results showed that the site effect was much stronger than the species effect for all elements and saturation isothermal remanent magnetisation (SIRM) values. Moreover, elements from traffic, industrial activity and soil dust are significantly correlated with leaf SIRM indicating that leaf SIRM can be a suitable bioindicator of exposure to traffic-derived particles and soil dust, and not from sea salts. It is concluded that chemical composition and SIRM of urban tree leaves can serve as a good indicator of atmospheric PM pollution in Iran and anywhere else where the studied trees grow. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000443329100034 |
Publication Date |
2018-07-02 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0944-1344; 1614-7499 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
2.741 |
Times cited |
6 |
Open Access |
|
|
Notes |
; ; |
Approved |
Most recent IF: 2.741 |
|
Call Number |
UA @ admin @ c:irua:153669 |
Serial |
5489 |
Permanent link to this record |
|
|
|
|
Author |
Kardel, F.; Wuyts, K.; De Wael, K.; Samson, R. |
|
Title |
Assessing atmospheric dry deposition via water-soluble ionic composition of roadside leaves |
Type |
A1 Journal article |
|
Year |
2020 |
Publication |
Journal of environmental science and health : part A: toxic/hazardous substances and environmental engineering |
Abbreviated Journal |
|
|
Volume |
|
Issue |
|
Pages |
1-9 |
|
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
Abstract |
This study focuses on the water-soluble ion concentrations in the washing solution of leaves of different roadside tree species at three sites in Iran to estimate the ionic composition of the dry deposition of ambient air particulates. All considered water-soluble ion concentrations were significantly higher next to the roads with high traffic density compared to the reference site with low traffic density. The PCA results showed that Ca2+, Mg2+, and originated mainly from traffic activities and geological sources, and Na+, Cl-, K+ and F- from sea salts. In addition to sea salt, K+ and F- were also originated from anthropogenic sources i.e. industrial activities, biomass burning and fluorite mining. Moreover, the concentration of the water-soluble ions depended on species and site. C. lawsoniana had significantly higher ion concentrations in its leaf washing solution compared to L. japonicum and P. brutia which indicates C. lawsoniana is the most suitable species for accumulating of atmospheric dry deposition. From our results, it can be concluded that sites with similar traffic density can have different particle loads and water-soluble ion species, and that concentrations in leaf-washing solutions depend on site conditions and species-specific leaf surface characteristics. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000527821700001 |
Publication Date |
2020-04-21 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
|
Times cited |
|
Open Access |
|
|
Notes |
; ; |
Approved |
Most recent IF: NA |
|
Call Number |
UA @ admin @ c:irua:169584 |
Serial |
6451 |
Permanent link to this record |
|
|
|
|
Author |
Kartal, S.; Dogan, M.; Rojas, C.M.; Van Grieken, R. |
|
Title |
Composition and sources of atmospheric particulate matter at Kayseri, Central Turkey |
Type |
A1 Journal article |
|
Year |
1993 |
Publication |
The science of the total environment |
Abbreviated Journal |
|
|
Volume |
133 |
Issue |
|
Pages |
83-97 |
|
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
|
Abstract |
|
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
A1993LA92200005 |
Publication Date |
2003-09-12 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0048-9697; 1879-1026 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
|
Times cited |
|
Open Access |
|
|
Notes |
|
Approved |
no |
|
Call Number |
UA @ admin @ c:irua:6251 |
Serial |
7703 |
Permanent link to this record |
|
|
|
|
Author |
Kashiwar, A. |
|
Title |
TEM investigations of deformation mechanisms in nanocrystalline metals and multilayered composites |
Type |
Doctoral thesis |
|
Year |
2022 |
Publication |
|
Abbreviated Journal |
|
|
Volume |
|
Issue |
|
Pages |
xvi, 129 p. |
|
Keywords |
Doctoral thesis; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
In the last few decades, nanostructuring has driven significant attention towards the development of novel metallic materials with advanced mechanical properties. Nanocrystalline (nc) metals are a class of nanostructured materials with grain sizes smaller than about 100 nm. These exhibit outstanding mechanical strength and fatigue properties compared to their coarse-grained (cg) counterparts. These are promising candidates for application as structural or functional materials. Nc metals in the form of thin films are employed as hard coatings on bulk components, structural components, and conductive layers in various micro-/nanoscale devices. These structural components and devices are often subjected to cyclic stresses or fatigue loading. Under these cyclic stresses, nc metals tend to exhibit the Bauschinger effect (BE). The strength loss during the BE is of great importance concerning the strength-ductility trade-off in nc metals. Furthermore, contact surfaces of the engineering components in service often undergo relative motion and are subject to both friction and wear. These extreme loading conditions demand nc metals with tailored interfacial characteristics for improved tribological performance. Aiming at ensuring high reliability and mechanical robustness for optimum performance of these components, there has been a strong motivation for understanding the mechanical properties and governing deformation mechanisms in nc metallic materials. This thesis aimed at in-depth investigation of microstructures at micro-/nanoscales using state-of-the-art in situ and ex situ transmission electron microscopy (TEM) to develop a closer link between the deformation structure and underlying deformation mechanisms in some nc metallic materials. The thesis has primarily focused on the in situ TEM nanomechanics of the BE and rotational deformation of grains in nc palladium thin films. A sputtered thin film of nc Pd was deformed inside TEM by cyclic loading-unloading experiments and the evolving microstructure was studied in real-time under different TEM imaging modes. The stress-strain response of the film exhibited a characteristic non-linear unloading behavior confirming the BE in the film. The corresponding bright-field TEM imaging revealed evidence of partially reversible dislocation activity. Towards a quantitative understanding of the deformation structure in real-time, in situ nanomechanical testing was coupled with precession-assisted automated crystal orientation mapping in scanning TEM (ACOM-STEM). Global ACOM-STEM analysis offered crystal orientation of a large number of grains at different states of deformation and confirmed partially reversible rotations of nanosized grains fitting to the observed BE during loading and unloading. Analysis of intragranular rotations showed substantial changes in the sub-structure within most of these grains indicating a dominant role of dislocation-based processes in driving these rotations. Globally, an unusually random evolution of texture was seen that demonstrated the influence of deformation heterogeneity and grain interactions on the resulting texture characteristics in nc metals. In the quest of understanding the grain interactions, local investigations based on annular dark-field STEM imaging during loading-unloading showed reversible changes in the contrast of grains with sets of adjoining grains exhibiting a unique cooperative rotation. Local analysis of the density of geometrically necessary dislocations (GNDs) showed the formation of dislocation pile-up at grain boundaries due to the generation of back-stresses during unloading. Critical observations of the evolution of GND density offered greater insights into the mechanism of cooperative grain rotations and these rotations were related to grain structure and grain boundary characteristics. In addition to understanding the influence of grain structure and grain boundaries, the thesis has further investigated the role of heterointerfaces in sputtered Au-Cu and Cu-Cr nanocrystalline multilayered composites (NMCs) deformed under cyclic sliding contact. The microstructural evolution in the NMCs was investigated at different deformation states by classical TEM imaging, ACOM-STEM as well as energy-filtered TEM (EFTEM). Au-Cu NMC with an initial high density of twin boundaries deformed by stress-driven detwinning with a concurrent change in grain structure in both Au and Cu. The formation of a vortex structure was observed due to plastic flow instabilities at Au-Cu interfaces that led to codeformation and mechanical intermixing. Cu-Cr NMC showed a preferential grain growth in Cu layers whereas no noticeable change in the grain sizes was seen in Cr layers. The phase maps revealed sharp interfaces between Cu and Cr layers indicating no intermixing between the immiscible phases. EFTEM results exposed the cracking processes in Cr layers with a concurrent migration of Cu in the cracks. Overall, the thesis has attempted to analyze the competing deformation processes and relate these with the microstructural heterogeneity in terms of grain structure and GB and interfacial characteristics in nc metallic materials. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
|
Publication Date |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record |
|
Impact Factor |
|
Times cited |
|
Open Access |
OpenAccess |
|
Notes |
|
Approved |
Most recent IF: NA |
|
Call Number |
UA @ admin @ c:irua:189013 |
Serial |
7343 |
Permanent link to this record |
|
|
|
|
Author |
Kashiwar, A.; Arseenko, M.; Simar, A.; Idrissi, H. |
|
Title |
On the role of microstructural defects on precipitation, damage, and healing behavior in a novel Al-0.5Mg2Si alloy |
Type |
A1 Journal article |
|
Year |
2024 |
Publication |
Materials & design |
Abbreviated Journal |
|
|
Volume |
239 |
Issue |
|
Pages |
112765-112769 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
A recently developed healable Al-Mg2Si designed by the programmed damage and repair (PDR) strategy is studied considering the role microstructural defects play on precipitation, damage, and healing. The alloy incorporates sacrificial Mg2Si particles that precipitate after friction stir processing (FSP). They act as damage localization sites and are healable based on the solid-state diffusion of Al-matrix. A combination of different transmission electron microscopy (TEM) imaging techniques enabled the visualization and quantification of various crystallographic defects and the spatial distribution of Mg2Si precipitates. Intragrain nucleation is found to be the dominant mechanism for precipitation during FSP whereas grain boundaries and subgrain boundaries mainly lead to coarsening of the precipitates. The statistical and spatial analyses of the damaged particles have shown particle fracture as the dominant damage mechanism which is strongly dependent on the size and aspect ratio of the particles whereas the damage was not found to depend on the location of the precipitates within the matrix. The damaged particles are associated with dislocations accumulated around them. The interplay of these dislocations is directly visualized during healing based on in situ TEM heating which revealed recovery in the matrix as an operative mechanism during the diffusion healing of the PDR alloy. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
001194110200001 |
Publication Date |
2024-02-17 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0264-1275; 1873-4197 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
|
Impact Factor |
8.4 |
Times cited |
|
Open Access |
Not_Open_Access |
|
Notes |
|
Approved |
Most recent IF: 8.4; 2024 IF: 4.364 |
|
Call Number |
UA @ admin @ c:irua:203298 |
Serial |
9068 |
Permanent link to this record |
|
|
|
|
Author |
Kashiwar, A.; Hahn, H.; Kubel, C. |
|
Title |
In situ TEM observation of cooperative grain rotations and the Bauschinger effect in nanocrystalline palladium |
Type |
A1 Journal article |
|
Year |
2021 |
Publication |
Nanomaterials |
Abbreviated Journal |
Nanomaterials-Basel |
|
Volume |
11 |
Issue |
2 |
Pages |
432 |
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
|
Abstract |
We report on cooperative grain rotation accompanied by a strong Bauschinger effect in nanocrystalline (nc) palladium thin film. A thin film of nc Pd was subjected to cyclic loading-unloading using in situ TEM nanomechanics, and the evolving microstructural characteristics were investigated with ADF-STEM imaging and quantitative ACOM-STEM analysis. ADF-STEM imaging revealed a partially reversible rotation of nanosized grains with a strong out-of-plane component during cyclic loading-unloading experiments. Sets of neighboring grains were shown to rotate cooperatively, one after the other, with increasing/decreasing strain. ACOM-STEM in conjunction with these experiments provided information on the crystallographic orientation of the rotating grains at different strain levels. Local Nye tensor analysis showed significantly different geometrically necessary dislocation (GND) density evolution within grains in close proximity, confirming a locally heterogeneous deformation response. The GND density analysis revealed the formation of dislocation pile-ups at grain boundaries (GBs), indicating the generation of back stresses during unloading. A statistical analysis of the orientation changes of individual grains showed the rotation of most grains without global texture development, which fits to both dislocation- and GB sliding-based mechanisms. Overall, our quantitative in situ experimental approach explores the roles of these different deformation mechanisms operating in nanocrystalline metals during cyclic loading. |
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
Language |
|
Wos |
000622951500001 |
Publication Date |
2021-02-14 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
2079-4991 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
3.553 |
Times cited |
|
Open Access |
OpenAccess |
|
Notes |
|
Approved |
Most recent IF: 3.553 |
|
Call Number |
UA @ admin @ c:irua:176770 |
Serial |
6729 |
Permanent link to this record |
|
|
|
|
Author |
Kastalsky, A.; Peeters, F.M.; Chan, W.K.; Florez, L.T.; Harbison, J.P. |
|
Title |
Nonlinear transport phenomena in a triangular quantum well |
Type |
A1 Journal article |
|
Year |
1991 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
|
Volume |
59 |
Issue |
|
Pages |
1708-1710 |
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
Abstract |
|
|
Address |
|
|
Corporate Author |
|
Thesis |
|
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
|
Language |
|
Wos |
A1991GH40900019 |
Publication Date |
0000-00-00 |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
ISSN |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
Impact Factor |
3.302 |
Times cited |
11 |
Open Access |
|
|
Notes |
|
Approved |
no |
|
Call Number |
UA @ lucian @ c:irua:945 |
Serial |
2360 |
Permanent link to this record |