Records |
Author |
Kaintura, A.; Foss, K.; Couckuyt, I.; Dhaene, T.; Zografos, O.; Vaysset, A.; Sorée, B. |
Title |
Machine Learning for Fast Characterization of Magnetic Logic Devices |
Type |
P1 Proceeding |
Year |
2018 |
Publication |
(edaps 2018) |
Abbreviated Journal |
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Volume |
|
Issue |
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Pages |
|
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
Non-charge-based logic devices are promising candidates for future logic circuits. Interest in studying and developing these devices has grown dramatically in the past decade as they possess key advantages over conventional CMOS technology. Due to their novel designs, a large number of micromagnetic simulations are required to fully characterize the behavior of these devices. The number and complexity of these simulations place large computational requirements on device development. We use state-of-the-art machine learning techniques to expedite identification of their behavior. Several intelligent sampling strategies are combined with machine learning multi-class classification models. These techniques are applied to a recently developed exchange-driven magnetic logic scheme that utilizes direct exchange coupling as the main driver. |
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 |
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Publication Date |
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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 |
978-1-5386-6592-3 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:160484 |
Serial |
5219 |
Permanent link to this record |
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Author |
Vishwakarma, M.; Thota, N.; Karakulina, O.; Hadermann, J.; Mehta, B.R. |
Title |
Role of graphene inter layer on the formation of the MoS2 – CZTS interface during growth |
Type |
P1 Proceeding |
Year |
2018 |
Publication |
(icc-2017) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
Abstract |
The growth of MoS2 layer near the Mo/CZTS interface during sulphurization process can have an impact on back contact cell parameters (series resistance and fill factor) depending upon the thickness or quality of MoS2. This study reports the dependence of the thickness of interfacial MoS2 layer on the growth of graphene at the interface between molybdenum back contact and deposited CZTS layer. The graphene layer reduces the accumulation of Zn/ZnS, Sn/SnO2 and formation of pores near the MoS2-CZTS interface. The use of graphene as interface layer can be potentially useful for improving the quality of Mo/MoS2/CZTS interface. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Amer inst physics |
Place of Publication |
Melville |
Editor |
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Language |
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Wos |
000436313003046 |
Publication Date |
2018-05-09 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
1953 |
Series Issue |
|
Edition |
|
ISSN |
978-0-7354-1648-2; 0094-243x; 0094-243x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
1 |
Open Access |
OpenAccess |
Notes |
; The authors acknowledge support provided by DST project. M.V. acknowledges IIT Delhi for MHRD fellowship. Prof. B. R. Mehta acknowledges the support of the Schlumberger chair professorship. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:153203 |
Serial |
5126 |
Permanent link to this record |
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Author |
Neilson, D.; Perali, A.; Zarenia, M. |
Title |
Many-body electron correlations in graphene |
Type |
P1 Proceeding |
Year |
2016 |
Publication |
(mbt18) |
Abbreviated Journal |
|
Volume |
702 |
Issue |
702 |
Pages |
012008 |
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
The conduction electrons in graphene promise new opportunities to access the region of strong many-body electron-electron correlations. Extremely high quality, atomically flat two-dimensional electron sheets and quasi-one-dimensional electron nanoribbons with tuneable band gaps that can be switched on by gates, should exhibit new many-body phenomena that have long been predicted for the regions of phase space where the average Coulomb repulsions between electrons dominate over their Fermi energies. In electron nanoribbons a few nanometres wide etched in monolayers of graphene, the quantum size effects and the van Hove singularities in their density of states further act to enhance electron correlations. For graphene multilayers or nanoribbons in a double unit electron-hole geometry, it is possible for the many-body electron-hole correlations to be made strong enough to stabilise high-temperature electron- hole superfluidity. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Iop publishing ltd |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000389756000008 |
Publication Date |
2016-04-29 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
702 |
Series Issue |
|
Edition |
|
ISSN |
1742-6588; 1742-6596 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
3 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:140268 |
Serial |
4455 |
Permanent link to this record |
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Author |
Van Aert, S.; den Dekker, A.J.; van den Bos, A.; Van Dyck, D. |
Title |
High resolution electron microscopy from imaging towards measuring |
Type |
H2 Book chapter |
Year |
2001 |
Publication |
... IEEE International Instrumentation and Measurement Technology Conference
T2 – Rediscovering measurement in the age of informatics : proceedings of the 18th IEEE Instrumentation and Measurement Technology Conference (IMTC), 2001: vol 3 |
Abbreviated Journal |
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Volume |
|
Issue |
|
Pages |
2081-2086 |
Keywords |
H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab |
Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Ieee |
Place of Publication |
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Editor |
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Language |
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Wos |
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Publication Date |
2002-11-13 |
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 |
|
ISSN |
|
ISBN |
0-7803-6646-8 |
Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:136870 |
Serial |
4501 |
Permanent link to this record |
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Author |
Lao, M.; Eisterer, M.; Stadel, O.; Meledin, A.; Van Tendeloo, G. |
Title |
The effect of Y2O3 and YFeO3 additions on the critical current density of YBCO coated conductors |
Type |
P1 Proceeding |
Year |
2014 |
Publication |
1-4 |
Abbreviated Journal |
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Volume |
|
Issue |
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Pages |
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Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
Abstract |
The pinning mechanism of MOCVD-grown YBCO coated conductors with Y2O3 precipitates was investigated by angle-resolved transport measurement of Je in a wide range of temperature and magnetic fields. Aside from the Y2O3 nanoprecipitates, a-axis grains and threading dislocation along the c-axis were found in the YBCO layer. The Y2O3 precipitates are less effective pinning centers at lower temperature. The tapes with precipitates show a higher anisotropy with larger J(c) at H parallel to ab than H parallel to c. This behavior was attributed to the preferred alignment of the nanoprecipitates along the ab-plane. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Iop publishing ltd |
Place of Publication |
Bristol |
Editor |
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Language |
|
Wos |
000350818300068 |
Publication Date |
2014-05-12 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
507 |
Series Issue |
|
Edition |
|
ISSN |
1742-6596; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
1 |
Open Access |
|
Notes |
eurotapes |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:125444 |
Serial |
3577 |
Permanent link to this record |
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Author |
Verreck, D.; Van de Put, M.L.; Verhulst, A.S.; Sorée, B.; Magnus, W.; Dabral, A.; Thean, A.; Groeseneken, G. |
Title |
15-band spectral envelope function formalism applied to broken gap tunnel field-effect transistors |
Type |
P1 Proceeding |
Year |
2015 |
Publication |
18th International Workshop On Computational Electronics (iwce 2015) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
A carefully chosen heterostructure can significantly boost the performance of tunnel field-effect transistors (TFET). Modelling of these hetero-TFETs requires a quantum mechanical (QM) approach with an accurate band structure to allow for a correct description of band-to-band-tunneling. We have therefore developed a fully QM 2D solver, combining for the first time a full zone 15-band envelope function formalism with a spectral approach, including a heterostructure basis set transformation. Simulations of GaSb/InAs broken gap TFETs illustrate the wide body capabilities and transparant transmission analysis of the formalism. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Ieee |
Place of Publication |
New york |
Editor |
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Language |
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Wos |
000380398200055 |
Publication Date |
2015-10-26 |
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 |
978-0-692-51523-5 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:134998 |
Serial |
4131 |
Permanent link to this record |
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Author |
Moors, K.; Sorée, B.; Magnus, W. |
Title |
Analytic solution of Ando's surface roughness model with finite domain distribution functions |
Type |
P1 Proceeding |
Year |
2015 |
Publication |
18th International Workshop On Computational Electronics (iwce 2015) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
Ando's surface roughness model is applied to metallic nanowires and extended beyond small roughness size and infinite barrier limit approximations for the wavefunction overlaps, such as the Prange-Nee approximation. Accurate and fast simulations can still be performed without invoking these overlap approximations by averaging over roughness profiles using finite domain distribution functions to obtain an analytic solution for the scattering rates. The simulations indicate that overlap approximations, while predicting a resistivity that agrees more or less with our novel approach, poorly estimate the underlying scattering rates. All methods show that a momentum gap between left- and right-moving electrons at the Fermi level, surpassing a critical momentum gap, gives rise to a substantial decrease in resistivity. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Ieee |
Place of Publication |
New york |
Editor |
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Language |
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Wos |
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Publication Date |
|
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 |
978-0-692-51523-5 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:134996 |
Serial |
4140 |
Permanent link to this record |
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Author |
Van de Put, M.L.; Vandenberghe, W.G.; Magnus, W.; Sorée, B.; Fischetti, M.V. |
Title |
Modeling of inter-ribbon tunneling in graphene |
Type |
P1 Proceeding |
Year |
2015 |
Publication |
18th International Workshop On Computational Electronics (iwce 2015) |
Abbreviated Journal |
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Volume |
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Issue |
|
Pages |
|
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
The tunneling current between two crossed graphene ribbons is described invoking the empirical pseudopotential approximation and the Bardeen transfer Hamiltonian method. Results indicate that the density of states is the most important factor determining the tunneling current between small (similar to nm) ribbons. The quasi-one dimensional nature of graphene nanoribbons is shown to result in resonant tunneling. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Ieee |
Place of Publication |
New york |
Editor |
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Language |
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Wos |
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Publication Date |
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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 |
978-0-692-51523-5 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:134997 |
Serial |
4206 |
Permanent link to this record |
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Author |
Liu, Y.; Brelet, Y.; He, Z.; Yu, L.; Mitryukovskiy, S.; Houard, A.; Forestier, B.; Couairon, A.; Mysyrowicz, A. |
Title |
Ciliary white light generated during femtosecond laser ablation on transparent dielectrics |
Type |
P1 Proceeding |
Year |
2013 |
Publication |
2013 Conference On And International Quantum Electronics Conference Lasers And Electro-optics Europe (cleo Europe/iqec) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
Abstract |
|
Address |
|
Corporate Author |
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Thesis |
|
Publisher |
Ieee |
Place of Publication |
New york |
Editor |
|
Language |
|
Wos |
|
Publication Date |
|
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
978-1-4799-0594-2 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:134446 |
Serial |
4494 |
Permanent link to this record |
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|
|
Author |
Verhulst, A.S.; Verreck, D.; Smets, Q.; Kao, K.-H.; Van de Put, M.; Rooyackers, R.; Sorée, B.; Vandooren, A.; De Meyer, K.; Groeseneken, G.; Heyns, M.M.; Mocuta, A.; Collaert, N.; Thean, A.V.-Y. |
Title |
Perspective of tunnel-FET for future low-power technology nodes |
Type |
P1 Proceeding |
Year |
2014 |
Publication |
2014 Ieee International Electron Devices Meeting (iedm) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
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Corporate Author |
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Thesis |
|
Publisher |
Ieee |
Place of Publication |
New york |
Editor |
|
Language |
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Wos |
|
Publication Date |
|
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
978-1-4799-8000-0 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:144789 |
Serial |
4679 |
Permanent link to this record |
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|
|
Author |
Adelmann, C.; Wen, L.G.; Peter, A.P.; Pourtois, G.; et al. |
Title |
Alternative metals for advanced interconnects |
Type |
P1 Proceeding |
Year |
2014 |
Publication |
2014 Ieee International Interconnect Technology Conference / Advanced Metallization Conference (iitc/amc) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
173-175 |
Keywords |
P1 Proceeding; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We discuss the selection criteria for alternative metals in order to fulfill the requirements necessary for interconnects at half pitch values below 10 nm. The performance of scaled interconnects using transition metal germanides and CoAl alloys as metallization are studied and compared to conventional Cu and W interconnects. |
Address |
|
Corporate Author |
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Thesis |
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Publisher |
Ieee |
Place of Publication |
New york |
Editor |
|
Language |
|
Wos |
|
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
978-1-4799-5018-8 |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:127033 |
Serial |
91 |
Permanent link to this record |
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|
|
Author |
Sankaran, K.; Clima, S.; Mees, M.; Adelmann, C.; Tokei, Z.; Pourtois, G. |
Title |
Exploring alternative metals to Cu and W for interconnects : an ab initio Insight |
Type |
P1 Proceeding |
Year |
2014 |
Publication |
2014 Ieee International Interconnect Technology Conference / Advanced Metallization Conference (iitc/amc) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
193-195 |
Keywords |
P1 Proceeding; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The properties of alternative metals to Cu and W for interconnect applications are reviewed based on first-principles simulations and benchmarked in terms of intrinsic bulk resistivity and electromigration. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Ieee |
Place of Publication |
New york |
Editor |
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Language |
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Wos |
|
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
978-1-4799-5018-8 |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:127034 |
Serial |
1149 |
Permanent link to this record |
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Author |
Van de Put, M.; Thewissen, M.; Magnus, W.; Sorée, B.; Sellier, J.M. |
Title |
Spectral force approach to solve the time-dependent Wigner-Liouville equation |
Type |
P1 Proceeding |
Year |
2014 |
Publication |
2014 International Workshop On Computational Electronics (iwce) |
Abbreviated Journal |
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Volume |
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Issue |
|
Pages |
|
Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
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Corporate Author |
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Thesis |
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Publisher |
Ieee |
Place of Publication |
New york |
Editor |
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Language |
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Wos |
|
Publication Date |
0000-00-00 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
978-1-4799-5433-9 |
ISBN |
|
Additional Links |
UA library record; WoS full record; |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:122221 |
Serial |
3071 |
Permanent link to this record |
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|
|
Author |
Yu, H.; Schaekers, M.; Chew, S.A.; Eyeraert, J.-L.; Dabral, A.; Pourtois, G.; Horiguchi, N.; Mocuta, D.; Collaert, N.; De Meyer, K. |
Title |
Titanium (germano-)silicides featuring 10-9 Ω.cm2 contact resistivity and improved compatibility to advanced CMOS technology |
Type |
P1 Proceeding |
Year |
2018 |
Publication |
2018 18th International Workshop On Junction Technology (iwjt) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
80-84
T2 - 18th International Workshop on Junction |
Keywords |
P1 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
uIn this work, we discuss three novel Ti (germano-)silicidation techniques featuring respectively the pre-contact amorphization implantation (PCAI), the TiSi co-deposition, and Ti atomic layer deposition (ALD). All three techniques form TiSix(Ge-y) contacts with ultralow contact resistivity (rho(c)) of (1-3)x10(-9) Omega.cm(2) on both highly doped n-Si and p-SiGe substrates: these techniques meet rho(c) requirement of 5-14 nm CMOS technology and feature unified CMOS contact solutions. We further discuss the compatibility of these techniques to the realistic CMOS transistor fabrication. |
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 |
000502768600020 |
Publication Date |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
978-1-5386-4511-6; 978-1-5386-4511-6 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:165190 |
Serial |
8673 |
Permanent link to this record |
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Author |
Conings, B.; Babayigit, A.; Klug, M.; Bai, S.; Gauquelin, N.; Sakai, N.; Wang, J.T.-W.; Verbeeck, J.; Boyen, H.-G.; Snaith, H. |
Title |
Getting rid of anti-solvents: gas quenching for high performance perovskite solar cells |
Type |
P1 Proceeding |
Year |
2018 |
Publication |
2018 Ieee 7th World Conference On Photovoltaic Energy Conversion (wcpec)(a Joint Conference Of 45th Ieee Pvsc, 28th Pvsec & 34th Eu Pvsec) |
Abbreviated Journal |
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Volume |
|
Issue |
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Pages |
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Keywords |
P1 Proceeding; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
As the field of perovskite optoelectronics developed, a plethora of strategies has arisen to control their electronic and morphological characteristics for the purpose of producing high efficiency devices. Unfortunately, despite this wealth of deposition approaches, the community experiences a great deal of irreproducibility between different laboratories, batches and preparation methods. Aiming to address this issue, we developed a simple deposition method based on gas quenching that yields smooth films for a wide range of perovskite compositions, in single, double, triple and quadruple cation varieties, and produces planar heterojunction devices with competitive efficiencies, so far up to 20%. |
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 |
000469200401163 |
Publication Date |
2018-12-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
978-1-5386-8529-7 |
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:160468 |
Serial |
5365 |
Permanent link to this record |
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|
|
Author |
Sankaran, K.; Swerts, J.; Carpenter, R.; Couet, S.; Garello, K.; Evans, R.F.L.; Rao, S.; Kim, W.; Kundu, S.; Crotti, D.; Kar, G.S.; Pourtois, G. |
Title |
Evidence of magnetostrictive effects on STT-MRAM performance by atomistic and spin modeling |
Type |
P1 Proceeding |
Year |
2018 |
Publication |
2018 Ieee International Electron Devices Meeting (iedm) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
P1 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
For the first time, we demonstrate, using an atomistic description of a 30nm diameter spin-transfer-torque magnetic random access memories (STT-MRAM), that the difference in mechanical properties of its sub-nanometer layers induces a high compressive strain in the magnetic tunnel junction (MTJ) and leads to a detrimental magnetostrictive effect. Our model explains the issues met in engineering the electrical and magnetic performances in scaled STT-MRAM devices. The resulting high compressive strain built in the stack, particularly in the MgO tunnel barrier (t-MgO), and its associated non-uniform atomic displacements, impacts on the quality of the MTJ interface and leads to strain relieve mechanisms such as surface roughness and adhesion issues. We illustrate that the strain gradient induced by the different materials and their thicknesses in the stacks has a negative impact on the tunnel magneto-resistance (TMR), on the magnetic nucleation process and on the STT-MRAM performance. |
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 |
000459882300147 |
Publication Date |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
978-1-72811-987-8; 978-1-72811-987-8 |
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:158694 |
Serial |
7942 |
Permanent link to this record |
|
|
|
Author |
Clima, S.; McMitchell, S.R.C.; Florent, K.; Nyns, L.; Popovici, M.; Ronchi, N.; Di Piazza, L.; Van Houdt, J.; Pourtois, G. |
Title |
First-principles perspective on poling mechanisms and ferroelectric/antiferroelectric behavior of Hf1-xZrxO2 for FEFET applications |
Type |
P1 Proceeding |
Year |
2018 |
Publication |
2018 Ieee International Electron Devices Meeting (iedm) |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
|
Keywords |
P1 Proceeding; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We investigate at the atomic level the most probable phase transformations under strain, that are responsible for the ferroelectric/ antiferroelectric behavior in Hf1-xZrxO2 materials. Four different crystalline phase transformations exhibit a polar/non-polar transition: monoclinic-to-orthorhombic requires a gliding strain tensor, orthorhombic-to-orthorhombic transformation does not need strain to polarize the material, whereas tetragonal-to-cubic cell compression and tetragonal-to-orthorhombic cell elongation destabilizes the non-polar tetragonal phase, facilitating the transition towards a polar atomic configuration, therefore changing the polarization-electric field loop from antiferroelectric to ferroelectric. Oxygen vacancies can reduce drastically the polarization reversal barriers. |
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 |
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Language |
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Wos |
000459882300073 |
Publication Date |
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
978-1-72811-987-8; 978-1-72811-987-8 |
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:158693 |
Serial |
7972 |
Permanent link to this record |
|
|
|
Author |
Scalise, E.; Houssa, M.; Cinquanta, E.; Grazianetti, C.; van den Broek, B.; Pourtois, G.; Stesmans, A.; Fanciulli, M.; Molle, A. |
Title |
Engineering the electronic properties of silicene by tuning the composition of MoX2 and GaX (X = S,Se,Te) chalchogenide templates |
Type |
A1 Journal article |
Year |
2014 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
1 |
Issue |
1 |
Pages |
011010 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
By using first-principles simulations, we investigate the interaction of a 2D silicon layer with two classes of chalcogenide-layered compounds, namely MoX2 and GaX (X = S, Se, Te). A rather weak (van der Waals) interaction between the silicene layers and the chalcogenide layers is predicted. We found that the buckling of the silicene layer is correlated to the lattice mismatch between the silicene layer and the MoX2 or GaX template. The electronic properties of silicene on these different templates largely depend on the buckling of the silicene layer: highly buckled silicene on MoS2 is predicted to be metallic, while low buckled silicene on GaS and GaSe is predicted to be semi-metallic, with preserved Dirac cones at the K points. These results indicate new routes for artificially engineering silicene nanosheets, providing tailored electronic properties of this 2D layer on non-metallic substrates. These non-metallic templates also open the way to the possible integration of silicene in future nanoelectronic devices. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000353649900011 |
Publication Date |
2014-05-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1583; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
49 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 6.937; 2014 IF: NA |
Call Number |
UA @ lucian @ c:irua:126032 |
Serial |
1048 |
Permanent link to this record |
|
|
|
Author |
Van Duppen, B.; Tomadin, A.; Grigorenko, A.N.; Polini, M. |
Title |
Current-induced birefringent absorption and non-reciprocal plasmons in graphene |
Type |
A1 Journal article |
Year |
2016 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
3 |
Issue |
3 |
Pages |
015011 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We present extensive calculations of the optical and plasmonic properties of a graphene sheet carrying a dc current. By calculating analytically the density-density response function of current-carrying states at finite temperature, we demonstrate that an applied dc current modifies the Pauli blocking mechanism and that absorption acquires a birefringent character with respect to the angle between the in-plane light polarization and current flow. Employing the random phase approximation at finite temperature, we show that graphene plasmons display a degree of non-reciprocity and collimation that can be tuned with the applied current. We discuss the possibility to measure these effects. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000373936300031 |
Publication Date |
2016-02-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
5 |
Open Access |
|
Notes |
This work was supported by the EC under the Graphene Flagship program (contract no. CNECT- ICT-604391) and MIUR through the program ‘Pro- getti Premiali 2012’ – Project ‘ABNANOTECH’. B.V. D. wishes to thank the Scuola Normale Superiore (Pisa, Italy) for the kind hospitality while this work was carried out and Research Foundation Flanders (FWO- Vl) for a PhD Fellowship. |
Approved |
Most recent IF: 6.937 |
Call Number |
c:irua:131900 c:irua:131900 |
Serial |
4017 |
Permanent link to this record |
|
|
|
Author |
Leenaerts, O.; Vercauteren, S.; Schoeters, B.; Partoens, B. |
Title |
System-size dependent band alignment in lateral two-dimensional heterostructures |
Type |
A1 Journal article |
Year |
2016 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
3 |
Issue |
3 |
Pages |
025012 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The electronic band alignment in semiconductor heterostructures is a key factor for their use in electronic applications. The alignment problem has been intensively studied for bulk systems but is less well understood for low-dimensional heterostructures. In this work we investigate the alignment in two-dimensional lateral heterostructures. First-principles calculations are used to show that the electronic band offset depends crucially on the width and thickness of the heterostructure slab. The particular heterostructures under study consist of thin hydrogenated and fluorinated diamond slabs which are laterally joined together. Two different limits for the band offset are observed. For infinitely wide heterostructures the vacuum potential above the two materials is aligned leading to a large step potential within the heterostructure. For infinitely thick heterostructure slabs, on the other hand, there is no potential step in the heterostructure bulk, but a large potential step in the vacuum region above the heterojunction is observed. The band alignment in finite systems depends on the particular dimensions of the system. These observations are shown to result from an interface dipole at the heterojunction that tends to align the band structures. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000378571400032 |
Publication Date |
2016-04-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
19 |
Open Access |
|
Notes |
This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government— department EWI. |
Approved |
Most recent IF: 6.937 |
Call Number |
c:irua:132792 c:irua:132792 |
Serial |
4055 |
Permanent link to this record |
|
|
|
Author |
Ozaydin, H.D.; Sahin, H.; Kang, J.; Peeters, F.M.; Senger, R.T. |
Title |
Electronic and magnetic properties of 1T-TiSe2 nanoribbons |
Type |
A1 Journal article |
Year |
2015 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
2 |
Issue |
2 |
Pages |
044002 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Motivated by the recent synthesis of single layer TiSe2, we used state-of-the-art density functional theory calculations, to investigate the structural and electronic properties of zigzag and armchair-edged nanoribbons (NRs) of this material. Our analysis reveals that, differing from ribbons of other ultra-thin materials such as graphene, TiSe2 NRs have some distinctive properties. The electronic band gap of the NRs decreases exponentially with the width and vanishes for ribbons wider than 20 angstrom. For ultranarrow zigzag-edged NRs we find odd-even oscillations in the band gap width, although their band structures show similar features. Moreover, our detailed magnetic-ground-state analysis reveals that zigzag and armchair edged ribbons have non-magnetic ground states. Passivating the dangling bonds with hydrogen at the edges of the structures influences the band dispersion. Our results shed light on the characteristic properties of T phase NRs of similar crystal structures. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000368936600005 |
Publication Date |
2015-10-13 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
20 |
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 ULAK-BIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus Short Marie Curie Fellowship. HDO, HS and RTS acknowledge the support from TUBITAK through project 114F397. ; |
Approved |
Most recent IF: 6.937; 2015 IF: NA |
Call Number |
UA @ lucian @ c:irua:131602 |
Serial |
4169 |
Permanent link to this record |
|
|
|
Author |
Van der Donck, M.; De Beule, C.; Partoens, B.; Peeters, F.M.; Van Duppen, B. |
Title |
Piezoelectricity in asymmetrically strained bilayer graphene |
Type |
A1 Journal article |
Year |
2016 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
3 |
Issue |
3 |
Pages |
035015 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study the electronic properties of commensurate faulted bilayer graphene by diagonalizing the one-particle Hamiltonian of the bilayer system in a complete basis of Bloch states of the individual graphene layers. Our novel approach is very general and can be easily extended to any commensurate graphene-based heterostructure. Here, we consider three cases: (i) twisted bilayer graphene, (ii) bilayer graphene where triaxial stress is applied to one layer and (iii) bilayer graphene where uniaxial stress is applied to one layer. We show that the resulting superstructures can be divided into distinct classes, depending on the twist angle or the magnitude of the induced strain. The different classes are distinguished from each other by the interlayer coupling mechanism, resulting in fundamentally different low-energy physics. For the cases of triaxial and uniaxial stress, the individual graphene layers tend to decouple and we find significant charge transfer between the layers. In addition, this piezoelectric effect can be tuned by applying a perpendicular electric field. Finally, we show how our approach can be generalized to multilayer systems. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000384072500003 |
Publication Date |
2016-08-31 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
10 |
Open Access |
|
Notes |
; This work was supported by the Research Foundation-Flanders (FWO-Vl) through aspirant research grants to MVDD, CDB, and BVD. ; |
Approved |
Most recent IF: 6.937 |
Call Number |
UA @ lucian @ c:irua:137203 |
Serial |
4361 |
Permanent link to this record |
|
|
|
Author |
van den Broek, B.; Houssa, M.; Scalise, E.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A. |
Title |
Two-dimensional hexagonal tin : ab initio geometry, stability, electronic structure and functionalization |
Type |
A1 Journal article |
Year |
2014 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
1 |
Issue |
|
Pages |
021004 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We study the structural, mechanical and electronic properties of the two-dimensional (2D) allotrope of tin: tinene/stanene using first-principles calculation within density functional theory, implemented in a set of computer codes. Continuing the trend of the group-IV 2D materials graphene, silicene and germanene; tinene is predicted to have a honeycomb lattice with lattice parameter of a(0) = 4.62 angstrom and a buckling of d(0) = 0.92 angstrom. The electronic dispersion shows a Dirac cone with zero gap at the Fermi energy and a Fermi velocity of v(F) = 0.97 x 10(6) m s(-1); including spin-orbit coupling yields a bandgap of 0.10 eV. The monolayer is thermally stable up to 700 K, as indicated by first-principles molecular dynamics, and has a phonon dispersion without imaginary frequencies. We explore applied electric field and applied strain as functionalization mechanisms. Combining these two mechanisms allows for an induced bandgap up to 0.21 eV, whilst retaining the linear dispersion, albeit with degraded electronic transport parameters. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000353650400004 |
Publication Date |
2014-08-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
58 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 6.937; 2014 IF: NA |
Call Number |
UA @ lucian @ c:irua:134432 |
Serial |
4530 |
Permanent link to this record |
|
|
|
Author |
van den Broek, B.; Houssa, M.; Iordanidou, K.; Pourtois, G.; Afanas'ev, V.V.; Stesmans, A. |
Title |
Functional silicene and stanene nanoribbons compared to graphene: electronic structure and transport |
Type |
A1 Journal article |
Year |
2016 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
3 |
Issue |
1 |
Pages |
015001 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Since the advent of graphene, other 2D materials have garnered interest; notably the single element materials silicene, germanene, and stanene. Weinvestigate the ballistic current-voltage (I-V) characteristics of armchair silicene and stanene armchair nanoribbons (AXNRs with X = Si, Sn) using a combination of density functional theory and non-equilibrium Green's functions. The impact of out-of-plane electric field and in-plane uniaxial strain on the ribbon geometries, electronic structure, and (I-V)s are considered and contrasted with graphene. Since silicene and stanene are sp(2)/sp(3) buckled layers, the electronic structure can be tuned by an electric field that breaks the sublattice symmetry, an effect absent in graphene. This decreases the current by similar to 50% for Sn, since it has the largest buckling. Uniaxial straining of the ballistic channel affects the AXNR electronic structure in multiple ways: it changes the bandgap and associated effective carrier mass, and creates a local buckling distortion at the lead-channel interface which induces a interface dipole. Due to the increasing sp(3) hybridization character with increasing element mass, large reconstructions rectify the strained systems, an effect absent in sp(2) bonded graphene. This results in a smaller strain effect on the current: a decrease of 20% for Sn at 15% tensile strain compared to a similar to 75% decrease for C. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000373936300021 |
Publication Date |
2016-01-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
19 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 6.937 |
Call Number |
UA @ lucian @ c:irua:144746 |
Serial |
4658 |
Permanent link to this record |
|
|
|
Author |
Sevik, C.; Wallbank, J.R.; Gulseren, O.; Peeters, F.M.; Çakir, D. |
Title |
Gate induced monolayer behavior in twisted bilayer black phosphorus |
Type |
A1 Journal article |
Year |
2017 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
4 |
Issue |
3 |
Pages |
035025 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Optical and electronic properties of black phosphorus strongly depend on the number of layers and type of stacking. Using first-principles calculations within the framework of density functional theory, we investigate the electronic properties of bilayer black phosphorus with an interlayer twist angle of 90 degrees. These calculations are complemented with a simple (k) over right arrow . (p) over right arrow model which is able to capture most of the low energy features and is valid for arbitrary twist angles. The electronic spectrum of 90 degrees twisted bilayer black phosphorus is found to be x-y isotropic in contrast to the monolayer. However x-y anisotropy, and a partial return to monolayer-like behavior, particularly in the valence band, can be induced by an external out-of-plane electric field. Moreover, the preferred hole effective mass can be rotated by 90 degrees simply by changing the direction of the applied electric field. In particular, a +0.4 (-0.4) V angstrom(1) out-of-plane electric field results in a similar to 60% increase in the hole effective mass along the y (x) axis and enhances the m(y)*/m(x)* (m(x)*/m(y)*) ratio as much as by a factor of 40. Our DFT and (k) over right arrow . (p) over right arrow simulations clearly indicate that the twist angle in combination with an appropriate gate voltage is a novel way to tune the electronic and optical properties of bilayer phosphorus and it gives us a new degree of freedom to engineer the properties of black phosphorus based devices. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000406926600001 |
Publication Date |
2017-08-03 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
13 |
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-Vl) 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), ERC Synergy grant Hetero2D and the EU Graphene Flagship Project. We also thank Vladimir Fal'ko for helpful discussions. ; |
Approved |
Most recent IF: 6.937 |
Call Number |
UA @ lucian @ c:irua:145151 |
Serial |
4717 |
Permanent link to this record |
|
|
|
Author |
Moldovan, D.; Masir, M.R.; Peeters, F.M. |
Title |
Magnetic field dependence of the atomic collapse state in graphene |
Type |
A1 Journal article |
Year |
2018 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
5 |
Issue |
1 |
Pages |
015017 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
<script type='text/javascript'>document.write(unpmarked('Quantum electrodynamics predicts that heavy atoms (Z \u003E Z(c) approximate to 170) will undergo the process of atomic collapse where electrons sink into the positron continuum and a new family of so-called collapsing states emerges. The relativistic electrons in graphene exhibit the same physics but at a much lower critical charge (Z(c) approximate to 1) which has made it possible to confirm this phenomenon experimentally. However, there exist conflicting predictions on the effect of a magnetic field on atomic collapse. These theoretical predictions are based on the continuum Dirac-Weyl equation, which does not have an exact analytical solution for the interplay of a supercritical Coulomb potential and the magnetic field. Approximative solutions have been proposed, but because the two effects compete on similar energy scales, the theoretical treatment varies depending on the regime which is being considered. These limitations are overcome here by starting from a tight-binding approach and computing exact numerical results. By avoiding special limit cases, we found a smooth evolution between the different regimes. We predict that the atomic collapse effect persists even after the magnetic field is activated and that the critical charge remains unchanged. We show that the atomic collapse regime is characterized: (1) by a series of Landau level anticrossings and (2) by the absence of root B scaling of the Landau levels with regard to magnetic field strength.')); |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000415015000001 |
Publication Date |
2017-10-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
13 |
Open Access |
|
Notes |
; We thank Eva Andrei, Jinhai Mao and Yuhang Jiang for insightful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Funding of the Flemish Government. ; |
Approved |
Most recent IF: 6.937 |
Call Number |
UA @ lucian @ c:irua:147361UA @ admin @ c:irua:147361 |
Serial |
4884 |
Permanent link to this record |
|
|
|
Author |
Peymanirad, F.; Singh, S.K.; Ghorbanfekr-Kalashami, H.; Novoselov, K.S.; Peeters, F.M.; Neek-Amal, M. |
Title |
Thermal activated rotation of graphene flake on graphene |
Type |
A1 Journal article |
Year |
2017 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
4 |
Issue |
2 |
Pages |
025015 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The self rotation of a graphene flake over graphite is controlled by the size, initial misalignment and temperature. Using both ab initio calculations and molecular dynamics simulations, we investigate annealing effects on the self rotation of a graphene flake on a graphene substrate. The energy barriers for rotation and drift of a graphene flake over graphene is found to be smaller than 25 meV/atom which is comparable to thermal energy. We found that small flakes (of about similar to 4 nm) are more sensitive to temperature and initial misorientation angles than larger one (beyond 10 nm). The initial stacking configuration of the flake is found to be important for its dynamics and time evolution of misalignment. Large flakes, which are initially in the AA-or AB-stacking state with small misorientation angle, rotate and end up in the AB-stacking configuration. However small flakes can they stay in an incommensurate state specially when the initial misorientation angle is larger than 2 degrees. Our results are in agreement with recent experiments. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000424399600005 |
Publication Date |
2017-02-02 |
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 |
2053-1583 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
16 |
Open Access |
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Notes |
; We would like to acknowledge Annalisa Fasolino and MM van Wijk for providing us with the implemented parameters of REBO-KC [5] in LAMMPS. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation. ; |
Approved |
Most recent IF: 6.937 |
Call Number |
UA @ lucian @ c:irua:149364 |
Serial |
4984 |
Permanent link to this record |
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Author |
Tiwari, S.; Van de Put, M.L.; Sorée, B.; Vandenberghe, W.G. |
Title |
Carrier transport in two-dimensional topological insulator nanoribbons in the presence of vacancy defects |
Type |
A1 Journal article |
Year |
2019 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
6 |
Issue |
2 |
Pages |
025011 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using the non-equilibrium Green's function formalism, we study carrier transport through imperfect two-dimensional (2D) topological insulator (TI) ribbons. In particular, we investigate the effect of vacancy defects on the carrier transport in 2D TI ribbons with hexagonal lattice structure. To account for the random distribution of the vacancy defects, we present a statistical study of varying defect densities by stochastically sampling different defect configurations. We demonstrate that the topological edge states of TI ribbons are fairly robust against a high concentration (up to 2%) of defects. At very high defect densities, we observe an increased inter-edge interaction, mediated by the localisation of the edge states within the bulk region. This effect causes significant back-scattering of the, otherwise protected, edge-states at very high defect concentrations (>2%), resulting in a loss of conduction through the TI ribbon. We discuss how this coherent vacancy scattering can be used to our advantage for the development of TI-based transistors. We find that there is an optimal concentration of vacancies yielding an ON-OFF current ratio of up to two orders of magnitude. Finally, we investigate the importance of spin-orbit coupling on the robustness of the edge states in the TI ribbon and show that increased spin-orbit coupling could further increase the ON-OFF ratio. |
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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 |
000457856400002 |
Publication Date |
2019-01-22 |
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 |
2053-1583 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
3 |
Open Access |
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Notes |
; This material is based in part upon work supported by the National Science Foundation under Grant Number 1710066. The project or effort depicted was or is sponsored by the Department of Defense, Defense Threat Reduction Agency. The content of the information does not necessarily reflect the position or the policy of the federal government, and no official endorsement should be inferred. This work was supported by imec's Industrial Affiliation Program. ; |
Approved |
Most recent IF: 6.937 |
Call Number |
UA @ admin @ c:irua:157464 |
Serial |
5198 |
Permanent link to this record |
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Author |
Li, L.L.; Partoens, B.; Xu, W.; Peeters, F.M. |
Title |
Electric-field modulation of linear dichroism and Faraday rotation in few-layer phosphorene |
Type |
A1 Journal article |
Year |
2019 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
6 |
Issue |
1 |
Pages |
015032 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Electro-optical modulators, which use an electric voltage (or an electric field) to modulate a beam of light, are essential elements in present-day telecommunication devices. Using a self-consistent tight-binding approach combined with the standard Kubo formula, we show that the optical conductivity and the linear dichroism of few-layer phosphorene can be modulated by a perpendicular electric field. We find that the field-induced charge screening plays a significant role in modulating the optical conductivity and the linear dichroism. Distinct absorption peaks are induced in the conductivity spectrum due to the strong quantum confinement along the out-of-plane direction and to the field-induced forbidden-to-allowed transitions. The field modulation of the linear dichroism becomes more pronounced with increasing number of phosphorene layers. We also show that the Faraday rotation is present in few-layer phosphorene even in the absence of an external magnetic field. This optical Hall effect is induced by the reduced lattice symmetry of few-layer phosphorene. The Faraday rotation is greatly influenced by the field-induced charge screening and is strongly dependent on the strength of perpendicular electric field and on the number of phosphorene layers. |
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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 |
000454321100002 |
Publication Date |
2018-11-28 |
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 |
2053-1583 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
23 |
Open Access |
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Notes |
; This work was financially supported by the Flemish Science Foundation (FWO-Vl) and by the FLAG-ERA project TRANS-2D-TMD. ; |
Approved |
Most recent IF: 6.937 |
Call Number |
UA @ admin @ c:irua:156776 |
Serial |
5207 |
Permanent link to this record |
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Author |
Heyne, M.H.; Marinov, D.; Braithwaite, N.; Goodyear, A.; de Marneffe, J.-F.; Cooke, M.; Radu, I.; Neyts, E.C.; De Gendt, S. |
Title |
A route towards the fabrication of 2D heterostructures using atomic layer etching combined with selective conversion |
Type |
A1 Journal article |
Year |
2019 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
6 |
Issue |
3 |
Pages |
035030 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Heterostructures of low-dimensional semiconducting materials, such as transition metal dichalcogenides (MX2), are promising building blocks for future electronic and optoelectronic devices. The patterning of one MX2 material on top of another one is challenging due to their structural similarity. This prevents an intrinsic etch stop when conventional anisotropic dry etching processes are used. An alternative approach consist in a two-step process, where a sacrificial silicon layer is pre-patterned with a low damage plasma process, stopping on the underlying MoS2 film. The pre-patterned layer is used as sacrificial template for the formation of the top WS2 film. This study describes the optimization of a cyclic Ar/Cl-2 atomic layer etch process applied to etch silicon on top of MoS2, with minimal damage, followed by a selective conversion of the patterned Si into WS2. The impact of the Si atomic layer etch towards the MoS2 is evaluated: in the ion energy range used for this study, MoS2 removal occurs in the over-etch step over 1-2 layers, leading to the appearance of MoOx but without significant lattice distortions to the remaining layers. The combination of Si atomic layer etch, on top of MoS2, and subsequent Si-to-WS2 selective conversion, allows to create a WS2/MoS2 heterostructure, with clear Raman signals and horizontal lattice alignment. These results demonstrate a scalable, transfer free method to achieve horizontally individually patterned heterostacks and open the route towards wafer-level processing of 2D materials. |
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 |
000468335500004 |
Publication Date |
2019-04-23 |
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 |
2053-1583 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
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Open Access |
Not_Open_Access |
Notes |
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Approved |
Most recent IF: 6.937 |
Call Number |
UA @ admin @ c:irua:160229 |
Serial |
5266 |
Permanent link to this record |