Records |
Author |
Li, L.L.; Xu, W.; Peeters, F.M. |
Title |
Optical conductivity of topological insulator thin films |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
117 |
Issue |
117 |
Pages |
175305 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We present a detailed theoretical study on the optoelectronic properties of topological insulator thin film (TITFs). The k . p approach is employed to calculate the energy spectra and wave functions for both the bulk and surface states in the TITF. With these obtained results, the optical conductivities induced by different electronic transitions among the bulk and surface states are evaluated using the energy-balance equation derived from the Boltzmann equation. We find that for Bi2Se3-based TITFs, three characteristic regimes for the optical absorption can be observed. (i) In the low radiation frequency regime (photon energy (h) over bar omega < 200 meV), the free-carrier absorption takes place due to intraband electronic transitions. An optical absorption window can be observed. (ii) In the intermediate radiation frequency regime (200 < (h) over bar omega < 300 meV), the optical absorption is induced mainly by interband electronic transitions from surface states in the valance band to surface states in the conduction band and an universal value sigma(0) = e(2) / (8<(h)over bar>) for the optical conductivity can be obtained. (iii) In the high radiation frequency regime ((h) over bar omega > 300 meV), the optical absorption can be achieved via interband electronic transitions from bulk and surface states in the valance band to bulk and surface states in the conduction band. A strong absorption peak can be observed. These interesting findings indicate that optical measurements can be applied to identify the energy regimes of bulk and surface states in the TITF. (C) 2015 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000354984100615 |
Publication Date |
2015-05-06 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979;1089-7550; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
9 |
Open Access |
|
Notes |
; This work was supported by the National Natural Science Foundation of China (Grant No. 11304316), Ministry of Science and Technology of China (Grant No. 2011YQ130018), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. ; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
c:irua:126412 |
Serial |
2473 |
Permanent link to this record |
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Author |
Zhao, C.X.; Xu, W.; Li, L.L.; Zhang, C.; Peeters, F.M. |
Title |
Terahertz plasmon-polariton modes in graphene driven by electric field inside a Fabry-Perot cavity |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
117 |
Issue |
117 |
Pages |
223104 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We present a theoretical study on plasmon-polariton modes in graphene placed inside an optical cavity and driven by a source-to-drain electric field. The electron velocity and electron temperature are determined by solving self-consistently the momentum-and energy-balance equations in which electron interactions with impurities, acoustic-, and optic-phonons are included. Based on many-body self-consistent field theory, we develop a tractable approach to study plasmon-polariton in an electron gas system. We find that when graphene is placed inside a Fabry-Perot cavity, two branches of the plasmon-polariton modes can be observed and these modes are very much optic-or plasmon-like. The frequencies of these modes depend markedly on driving electric field especially at higher resonant frequency regime. Moreover, the plasmon-polariton frequency in graphene is in terahertz (THz) bandwidth and can be tuned by changing the cavity length, gate voltage, and driving electric field. This work is pertinent to the application of graphene-based structures as tunable THz plasmonic devices. (C) 2015 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000356176100004 |
Publication Date |
2015-06-10 |
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 |
0021-8979;1089-7550; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
13 |
Open Access |
|
Notes |
; This work was supported by the Ministry of Science and Technology of China (Grant No. 2011YQ130018), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. F.M.P. was a specially appointed Professor for foreign expert at the Chinese Academy of Sciences. ; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
c:irua:127076 |
Serial |
3507 |
Permanent link to this record |
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Author |
Berdiyorov, G.R.; Bahlouli, H.; Peeters, F.M. |
Title |
Theoretical study of electronic transport properties of a graphene-silicene bilayer |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
117 |
Issue |
117 |
Pages |
225101 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Electronic transport properties of a graphene-silicene bilayer system are studied using density-functional theory in combination with the nonequilibrium Green's function formalism. Depending on the energy of the electrons, the transmission can be larger in this system as compared to the sum of the transmissions of separated graphene and silicene monolayers. This effect is related to the increased electron density of states in the bilayer sample. At some energies, the electronic states become localized in one of the layers, resulting in the suppression of the electron transmission. The effect of an applied voltage on the transmission becomes more pronounced in the layered sample as compared to graphene due to the larger variation of the electrostatic potential profile. Our findings will be useful when creating hybrid nanoscale devices where enhanced transport properties will be desirable. (C) 2015 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
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Wos |
000356176100040 |
Publication Date |
2015-06-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979;1089-7550; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
10 |
Open Access |
|
Notes |
; H. B. and F. M. P. acknowledge support from King Fahd University of Petroleum and Minerals, Saudi Arabia, under the RG1329-1 and RG1329-2 DSR Projects. ; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
c:irua:127075 |
Serial |
3611 |
Permanent link to this record |
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Author |
Schoeters, B.; Leenaerts, O.; Pourtois, G.; Partoens, B. |
Title |
Ab-initio study of the segregation and electronic properties of neutral and charged B and P dopants in Si and Si/SiO2 nanowires |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
118 |
Issue |
118 |
Pages |
104306 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We perform first-principles calculations to investigate the preferred positions of B and P dopants, both neutral and in their preferred charge state, in Si and Si/SiO2 core-shell nanowires (NWs). In order to understand the observed trends in the formation energy, we isolate the different effects that determine these formation energies. By making the distinction between the unrelaxed and the relaxed formation energy, we separate the impact of the relaxation from that of the chemical environment. The unrelaxed formation energies are determined by three effects: (i) the effect of strain caused by size mismatch between the dopant and the host atoms, (ii) the local position of the band edges, and (iii) a screening effect. In the case of the SiNW (Si/SiO2 NW), these effects result in an increase of the formation energy away from the center (interface). The effect of relaxation depends on the relative size mismatch between the dopant and host atoms. A large size mismatch causes substantial relaxation that reduces the formation energy considerably, with the relaxation being more pronounced towards the edge of the wires. These effects explain the surface segregation of the B dopants in a SiNW, since the atomic relaxation induces a continuous drop of the formation energy towards the edge. However, for the P dopants, the formation energy starts to rise when moving from the center but drops to a minimum just next to the surface, indicating a different type of behavior. It also explains that the preferential location for B dopants in Si/SiO2 core-shell NWs is inside the oxide shell just next to the interface, whereas the P dopants prefer the positions next to the interface inside the Si core, which is in agreement with recent experiments. These preferred locations have an important impact on the electronic properties of these core-shell NWs. Our simulations indicate the possibility of hole gas formation when B segregates into the oxide shell. |
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 |
000361636900031 |
Publication Date |
2015-09-09 |
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 |
0021-8979 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
3 |
Open Access |
|
Notes |
This work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish government and the Universiteit Antwerpen. |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
c:irua:128729 |
Serial |
4056 |
Permanent link to this record |
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Author |
Verreck, D.; Verhulst, A.S.; Van de Put, M.; Sorée, B.; Magnus, W.; Mocuta, A.; Collaert, N.; Thean, A.; Groeseneken, G. |
Title |
Full-zone spectral envelope function formalism for the optimization of line and point tunnel field-effect transistors |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
118 |
Issue |
118 |
Pages |
134502 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Efficient quantum mechanical simulation of tunnel field-effect transistors (TFETs) is indispensable to allow for an optimal configuration identification. We therefore present a full-zone 15-band quantum mechanical solver based on the envelope function formalism and employing a spectral method to reduce computational complexity and handle spurious solutions. We demonstrate the versatility of the solver by simulating a 40 nm wide In0.53Ga0.47As lineTFET and comparing it to p-n-i-n configurations with various pocket and body thicknesses. We find that the lineTFET performance is not degraded compared to semi-classical simulations. Furthermore, we show that a suitably optimized p-n-i-n TFET can obtain similar performance to the lineTFET. (C) 2015 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
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Wos |
000362668400025 |
Publication Date |
2015-10-01 |
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 |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
9 |
Open Access |
|
Notes |
; D. Verreck 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 supported by imec's Industrial Affiliation Program. ; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:128765 |
Serial |
4183 |
Permanent link to this record |
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Author |
Moors, K.; Sorée, B.; Magnus, W. |
Title |
Modeling surface roughness scattering in metallic nanowires |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
118 |
Issue |
118 |
Pages |
124307 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Ando's model provides a rigorous quantum-mechanical framework for electron-surface roughness scattering, based on the detailed roughness structure. We apply this method to metallic nanowires and improve the model introducing surface roughness distribution functions on a finite domain with analytical expressions for the average surface roughness matrix elements. This approach is valid for any roughness size and extends beyond the commonly used Prange-Nee approximation. The resistivity scaling is obtained from the self-consistent relaxation time solution of the Boltzmann transport equation and is compared to Prange-Nee's approach and other known methods. The results show that a substantial drop in resistivity can be obtained for certain diameters by achieving a large momentum gap between Fermi level states with positive and negative momentum in the transport direction. (C) 2015 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000362565800032 |
Publication Date |
2015-09-24 |
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 |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
11 |
Open Access |
|
Notes |
; ; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:129425 |
Serial |
4207 |
Permanent link to this record |
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Author |
Yagmurcukardes, M.; Sahin, H.; Kang, J.; Torun, E.; Peeters, F.M.; Senger, R.T. |
Title |
Pentagonal monolayer crystals of carbon, boron nitride, and silver azide |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
118 |
Issue |
118 |
Pages |
104303 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In this study, we present a theoretical investigation of structural, electronic, and mechanical properties of pentagonal monolayers of carbon (p-graphene), boron nitride (p-B2N4 and p-B4N2), and silver azide (p-AgN3) by performing state-of-the-art first principles calculations. Our total energy calculations suggest feasible formation of monolayer crystal structures composed entirely of pentagons. In addition, electronic band dispersion calculations indicate that while p-graphene and p-AgN3 are semiconductors with indirect bandgaps, p-BN structures display metallic behavior. We also investigate the mechanical properties (in-plane stiffness and the Poisson's ratio) of four different pentagonal structures under uniaxial strain. p-graphene is found to have the highest stiffness value and the corresponding Poisson's ratio is found to be negative. Similarly, p-B2N4 and p-B4N2 have negative Poisson's ratio values. On the other hand, the p-AgN3 has a large and positive Poisson's ratio. In dynamical stability tests based on calculated phonon spectra of these pentagonal monolayers, we find that only p-graphene and p-B2N4 are stable, but p-AgN3 and p-B4N2 are vulnerable against vibrational excitations. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000361636900028 |
Publication Date |
2015-09-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
79 |
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). H.S. was supported by a FWO Pegasus Long Marie Curie Fellowship. H.S. and R.T.S. acknowledge the support from TUBITAK through Project No. 114F397. ; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:128415 |
Serial |
4223 |
Permanent link to this record |
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Author |
de Sousa, A.A.; Chaves, A.; Pereira, T.A.S.; Farias, G.A.; Peeters, F.M. |
Title |
Quantum tunneling between bent semiconductor nanowires |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
118 |
Issue |
118 |
Pages |
174301 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We theoretically investigate the electronic transport properties of two closely spaced L-shaped semiconductor quantum wires, for different configurations of the output channel widths as well as the distance between the wires. Within the effective-mass approximation, we solve the time-dependent Schrodinger equation using the split-operator technique that allows us to calculate the transmission probability, the total probability current, the conductance, and the wave function scattering between the energy subbands. We determine the maximum distance between the quantum wires below which a relevant non-zero transmission is still found. The transmission probability and the conductance show a strong dependence on the width of the output channel for small distances between the wires. (C) 2015 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000364584200020 |
Publication Date |
2015-11-02 |
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 |
|
ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
7 |
Open Access |
|
Notes |
; A. A. Sousa was financially supported by CAPES, under the PDSE Contract No. BEX 7177/13-5. T. A. S. Pereira was financially supported by PRONEX/CNPq/FAPEMAT 850109/2009 and by CAPES under process BEX 3299/13-9. This work was financially supported by PRONEX/CNPq/FUNCAP, the Science Without Borders program and the bilateral project CNPq-FWO. ; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:129544 |
Serial |
4234 |
Permanent link to this record |
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Author |
Zhang, Y.; Jiang, W.; Zhang, Q.Z.; Bogaerts, A. |
Title |
Computational study of plasma sustainability in radio frequency micro-discharges |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
115 |
Issue |
19 |
Pages |
193301-193311 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We apply an implicit particle-in-cell Monte-Carlo (PIC-MC) method to study a radio-frequency argon microdischarge at steady state in the glow discharge limit, in which the microdischarge is sustained by secondary electron emission from the electrodes. The plasma density, electron energy distribution function (EEDF), and electron temperature are calculated in a wide range of operating conditions, including driving voltage, microdischarge gap, and pressure. Also, the effect of gap size scaling (in the range of 50-1000 μm) on the plasma sustaining voltage and peak electron density at atmospheric pressure is examined, which has not been explored before. In our simulations, three different EEDFs, i.e., a so-called three temperature hybrid mode, a two temperature α mode, and a two temperature γ mode distribution, are identified at different gaps and voltages. The maximum sustaining voltage to avoid a transition from the glow mode to an arc is predicted, as well as the minimum sustaining voltage for a steady glow discharge. Our calculations elucidate that secondary electrons play an essential role in sustaining the discharge, and as a result the relationship between breakdown voltage and gap spacing is far away from the Paschen law at atmospheric pressure. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000336920200010 |
Publication Date |
2014-05-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0021-8979;1089-7550; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2014 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:116948 |
Serial |
458 |
Permanent link to this record |
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Author |
Zhang, Q.-Z.; Wang, Y.-N.; Bogaerts, A. |
Title |
Heating mode transition in a hybrid direct current/dual-frequency capacitively coupled CF4 discharge |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
115 |
Issue |
22 |
Pages |
223302-223306 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Computer simulations based on the particle-in-cell/Monte Carlo collision method are performed to study the plasma characteristics and especially the transition in electron heating mechanisms in a hybrid direct current (dc)/dual-frequency (DF) capacitively coupled CF 4 discharge. When applying a superposed dc voltage, the plasma density first increases, then decreases, and finally increases again, which is in good agreement with experiments. This trend can be explained by the transition between the four main heating modes, i.e., DF coupling, dc and DF coupling, dc source dominant heating, and secondary electron dominant heating. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000337891800006 |
Publication Date |
2014-06-11 |
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 |
0021-8979;1089-7550; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
9 |
Open Access |
|
Notes |
|
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2014 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:117347 |
Serial |
1414 |
Permanent link to this record |
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Author |
Smets, Q.; Verreck, D.; Verhulst, A.S.; Rooyackers, R.; Merckling, C.; Van De Put, M.; Simoen, E.; Vandervorst, W.; Collaert, N.; Thean, V.Y.; Sorée, B.; Groeseneken, G.; Heyns, M.M.; |
Title |
InGaAs tunnel diodes for the calibration of semi-classical and quantum mechanical band-to-band tunneling models |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
115 |
Issue |
18 |
Pages |
184503-184509 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Promising predictions are made for III-V tunnel-field-effect transistor (FET), but there is still uncertainty on the parameters used in the band-to-band tunneling models. Therefore, two simulators are calibrated in this paper; the first one uses a semi-classical tunneling model based on Kane's formalism, and the second one is a quantum mechanical simulator implemented with an envelope function formalism. The calibration is done for In0.53Ga0.47As using several p+/intrinsic/n+ diodes with different intrinsic region thicknesses. The dopant profile is determined by SIMS and capacitance-voltage measurements. Error bars are used based on statistical and systematic uncertainties in the measurement techniques. The obtained parameters are in close agreement with theoretically predicted values and validate the semi-classical and quantum mechanical models. Finally, the models are applied to predict the input characteristics of In0.53Ga0.47As n- and p-lineTFET, with the n-lineTFET showing competitive performance compared to MOSFET. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000336919400048 |
Publication Date |
2014-05-14 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979;1089-7550; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
34 |
Open Access |
|
Notes |
; Quentin Smets and Devin Verreck gratefully acknowledge the support of a Ph. D. stipend from IWT-Vlaanderen. This work was supported by imec's industrial affiliation program. The authors thank Kim Baumans, Johan Feyaerts, Johan De Cooman, Alireza Alian, and Jos Moonens for their support in process development; Bastien Douhard and Joris Delmotte for SIMS characterization; Alain Moussa for AFM characterization; Joris Van Laer and Tom Daenen for their support in electrical characterization; Kuo-Hsing Kao, Mehbuba Tanzid, and Ali Pourghaderi for their support in modeling. ; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2014 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:118009 |
Serial |
1667 |
Permanent link to this record |
|
|
|
Author |
Milovanović, S.P.; Masir, M.R.; Peeters, F.M. |
Title |
Magnetic electron focusing and tuning of the electron current with a pn-junction |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
115 |
Issue |
4 |
Pages |
043719-6 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Transverse magnetic focusing properties of graphene using a ballistic four terminal structure are investigated. The electric response is obtained using the semiclassical billiard model. The transmission exhibits pronounced peaks as a consequence of skipping orbits at the edge of the structure. When we add a pn-junction between the two probes, snake states along the pn-interface appear. Injected electrons are guided by the pn-interface to one of the leads depending on the value of the applied magnetic field. Oscillations in the resistance are found depending on the amount of particles that end up in each lead. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000331210800066 |
Publication Date |
2014-01-30 |
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 |
21 |
Open Access |
|
Notes |
This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN, and the Methusalem Foundation of the Flemish government. |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2014 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:115801 |
Serial |
1866 |
Permanent link to this record |
|
|
|
Author |
Sen, H.S.; Sahin, H.; Peeters, F.M.; Durgun, E. |
Title |
Monolayers of MoS2 as an oxidation protective nanocoating material |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
116 |
Issue |
8 |
Pages |
083508 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
First-principle calculations are employed to investigate the interaction of oxygen with ideal and defective MoS2 monolayers. Our calculations show that while oxygen atoms are strongly bound on top of sulfur atoms, the oxygen molecule only weakly interacts with the surface. The penetration of oxygen atoms and molecules through a defect-free MoS2 monolayer is prevented by a very high diffusion barrier indicating that MoS2 can serve as a protective layer for oxidation. The analysis is extended to WS2 and similar coating characteristics are obtained. Our calculations indicate that ideal and continuous MoS2 and WS2 monolayers can improve the oxidation and corrosion-resistance of the covered surface and can be considered as an efficient nanocoating material. (C) 2014 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000342821600017 |
Publication Date |
2014-08-27 |
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 |
52 |
Open Access |
|
Notes |
; This work was supported by the bilateral project between TUBITAK (through Grant No. 113T050) and Flemish Science Foundation (FWO-Vl). The calculations were performed at TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). E.D. acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP program. H.S. is supported by an FWO Pegasus-long Marie Curie Fellowship. ; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2014 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:121101 |
Serial |
2194 |
Permanent link to this record |
|
|
|
Author |
Wen, D.-Q.; Zhang, Q.-Z.; Jiang, W.; Song, U.-H.; Bogaerts, A.; Wang, Y.-N. |
Title |
Phase modulation in pulsed dual-frequency capacitively coupled plasmas |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
115 |
Issue |
23 |
Pages |
233303 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Particle-in-cell/Monte Carlo collision simulations, coupled with an external circuit, are used to investigate the behavior of pulsed dual-frequency (DF) capacitively coupled plasmas (CCPs). It is found that the phase shift θ between the high (or low) frequency source and the pulse modulation has a great influence on the ion density and the ionization rate. By pulsing the high frequency source, the time-averaged ion density shows a maximum when θ = 90∘. The time-averaged ion energy distribution functions (IEDFs) at the driven electrode, however, keep almost unchanged, illustrating the potential of pulsed DF-CCP for independent control of ion density (and flux) and ion energy. A detailed investigation of the temporal evolution of the plasma characteristics indicates that several high frequency harmonics can be excited at the initial stage of a pulse period by tuning the phase shift θ, and this gives rise to strong sheath oscillations, and therefore high ionization rates. For comparison, the pulsing of the low frequency source is also studied. In this case, the ion density changes slightly as a function of time, and the time-averaged ion density shows the same trend as in the HF modulation for different phase shifts θ. Moreover, the time-averaged IEDFs at the driven electrode can be modulated, showing the potential to reduce the maximum ion bombardment energy. |
Address |
|
Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000338106000008 |
Publication Date |
2014-06-23 |
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 |
8 |
Open Access |
|
Notes |
|
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2014 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:117415 |
Serial |
2585 |
Permanent link to this record |
|
|
|
Author |
Verreck, D.; Van de Put, M.; Sorée, B.; Verhulst, A.S.; Magnus, W.; Vandenberghe, W.G.; Collaert, N.; Thean, A.; Groeseneken, G. |
Title |
Quantum mechanical solver for confined heterostructure tunnel field-effect transistors |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
115 |
Issue |
5 |
Pages |
053706-53708 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Heterostructure tunnel field-effect transistors (HTFET) are promising candidates for low-power applications in future technology nodes, as they are predicted to offer high on-currents, combined with a sub-60 mV/dec subthreshold swing. However, the effects of important quantum mechanical phenomena like size confinement at the heterojunction are not well understood, due to the theoretical and computational difficulties in modeling realistic heterostructures. We therefore present a ballistic quantum transport formalism, combining a novel envelope function approach for semiconductor heterostructures with the multiband quantum transmitting boundary method, which we extend to 2D potentials. We demonstrate an implementation of a 2-band version of the formalism and apply it to study confinement in realistic heterostructure diodes and p-n-i-n HTFETs. For the diodes, both transmission probabilities and current densities are found to decrease with stronger confinement. For the p-n-i-n HTFETs, the improved gate control is found to counteract the deterioration due to confinement. (C) 2014 AIP Publishing LLC. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000331645900040 |
Publication Date |
2014-02-05 |
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 |
15 |
Open Access |
|
Notes |
; D. Verreck 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 supported by imec's Industrial Affiliation Program. ; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2014 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:115825 |
Serial |
2780 |
Permanent link to this record |
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|
|
Author |
Moors, K.; Sorée, B.; Tokei, Z.; Magnus, W. |
Title |
Resistivity scaling and electron relaxation times in metallic nanowires |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
116 |
Issue |
6 |
Pages |
063714 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study the resistivity scaling in nanometer-sized metallic wires due to surface roughness and grain-boundaries, currently the main cause of electron scattering in nanoscaled interconnects. The resistivity has been obtained with the Boltzmann transport equation, adopting the relaxation time approximation of the distribution function and the effective mass approximation for the conducting electrons. The relaxation times are calculated exactly, using Fermi's golden rule, resulting in a correct relaxation time for every sub-band state contributing to the transport. In general, the relaxation time strongly depends on the sub-band state, something that remained unclear with the methods of previous work. The resistivity scaling is obtained for different roughness and grain-boundary properties, showing large differences in scaling behavior and relaxation times. Our model clearly indicates that the resistivity is dominated by grain-boundary scattering, easily surpassing the surface roughness contribution by a factor of 10. (C) 2014 AIP Publishing LLC. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000341179400036 |
Publication Date |
2014-08-15 |
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 |
17 |
Open Access |
|
Notes |
; ; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2014 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:119260 |
Serial |
2882 |
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 |
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Corporate Author |
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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 ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2014 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:115800 |
Serial |
3505 |
Permanent link to this record |
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|
|
Author |
Li, D.Y.; Zeng, Y.J.; Pereira, L.M.C.; Batuk, D.; Hadermann, J.; Zhang, Y.Z.; Ye, Z.Z.; Temst, K.; Vantomme, A.; Van Bael, M.J.; Van Haesendonck, C.; |
Title |
Anisotropic magnetism and spin-dependent transport in Co nanoparticle embedded ZnO thin films |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
114 |
Issue |
3 |
Pages |
033909-6 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Oriented Co nanoparticles were obtained by Co ion implantation in crystalline ZnO thin films grown by pulsed laser deposition. Transmission electron microscopy revealed the presence of elliptically shaped Co precipitates with nanometer size, which are embedded in the ZnO thin films, resulting in anisotropic magnetic behavior. The low-temperature resistance of the Co-implanted ZnO thin films follows the Efros-Shklovskii type variable-range-hopping. Large negative magnetoresistance (MR) exceeding 10% is observed in a magnetic field of 1 T at 2.5K and the negative MR survives up to 250K (0.3%). The negative MR reveals hysteresis as well as anisotropy that correlate well with the magnetic properties, clearly demonstrating the presence of spin-dependent transport. (C) 2013 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000322202700071 |
Publication Date |
2013-07-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
10 |
Open Access |
|
Notes |
|
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2013 IF: 2.185 |
Call Number |
UA @ lucian @ c:irua:110765 |
Serial |
126 |
Permanent link to this record |
|
|
|
Author |
Milovanovic, S.P.; Masir, M.R.; Peeters, F.M. |
Title |
Bilayer graphene Hall bar with a pn-junction |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
114 |
Issue |
11 |
Pages |
113706 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate the magnetic field dependence of the Hall and the bend resistances for a ballistic Hall bar structure containing a pn-junction sculptured from a bilayer of graphene. The electric response is obtained using the billiard model, and we investigate the cases of bilayer graphene with and without a band gap. Two different conduction regimes are possible: (i) both sides of the junction have the same carrier type and (ii) one side of the junction is n-type while the other one is p-type. The first case shows Hall plateau-like features in the Hall resistance that fade away as the band gap opens. The second case exhibits a bend resistance that is asymmetric in magnetic field as a consequence of snake states along the pn-interface, where the maximum is shifted away from zero magnetic field. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000324827200031 |
Publication Date |
2013-09-17 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
3 |
Open Access |
|
Notes |
This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN, and the Methusalem Foundation of the Flemish government. |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2013 IF: 2.185 |
Call Number |
UA @ lucian @ c:irua:111169 |
Serial |
234 |
Permanent link to this record |
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|
|
Author |
Seyed-Talebi, S.M.; Beheshtian, J.; Neek-Amal, M. |
Title |
Doping effect on the adsorption of NH3 molecule onto graphene quantum dot : from the physisorption to the chemisorption |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
114 |
Issue |
12 |
Pages |
124307-7 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The adsorption of ammonia molecule onto a graphene hexagonal flake, aluminum (Al) and boron (B) doped graphene flakes (graphene quantum dots, GQDs) are investigated using density functional theory. We found that NH3 molecule is absorbed to the hollow site through the physisorption mechanism without altering the electronic properties of GQD. However, the adsorption energy of NH3 molecule onto the Al- and B-doped GQDs increases with respect GQD resulting chemisorption. The adsorption of NH3 onto the Al-doped and B-doped GQDs makes graphene locally buckled, i.e., B-doped and Al-doped GQDs are not planar. The adsorption mechanism onto a GQD is different than that of graphene. This study reveals important features of the edge passivation and doping effects of the adsorption mechanism of external molecules onto the graphene quantum dots. (C) 2013 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
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Wos |
000325391100057 |
Publication Date |
2013-09-26 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
10 |
Open Access |
|
Notes |
; This work was supported by the EU-Marie Curie IIF Fellowship/299855 for M.-N.A. ; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2013 IF: 2.185 |
Call Number |
UA @ lucian @ c:irua:112201 |
Serial |
750 |
Permanent link to this record |
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|
|
Author |
Comrie, C.M.; Ahmed, A.; Smeets, D.; Demeulemeester, J.; Turner, S.; Van Tendeloo, G.; Detavernier, C.; Vantomme, A. |
Title |
Effect of high temperature deposition on CoSi2 phase formation |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
113 |
Issue |
23 |
Pages |
234902-234908 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
This paper discusses the nucleation behaviour of the CoSi to CoSi2 transformation from cobalt silicide thin films grown by deposition at elevated substrate temperatures ranging from 375 °C to 600 °C. A combination of channelling, real-time Rutherford backscattering spectrometry, real-time x-ray diffraction, and transmission electron microscopy was used to investigate the effect of the deposition temperature on the subsequent formation temperature of CoSi2, its growth behaviour, and the epitaxial quality of the CoSi2 thus formed. The temperature at which deposition took place was observed to exert a significant and systematic influence on both the formation temperature of CoSi2 and its growth mechanism. CoSi films grown at the lowest temperatures were found to increase the CoSi2 nucleation temperature above that of CoSi2 grown by conventional solid phase reaction, whereas the higher deposition temperatures reduced the nucleation temperature significantly. In addition, a systematic change in growth mechanism of the subsequent CoSi2 growth occurs as a function of deposition temperature. First, the CoSi2 growth rate from films grown at the lower reactive deposition temperatures is substantially lower than that grown at higher reactive deposition temperatures, even though the onset of growth occurs at a higher temperature, Second, for deposition temperatures below 450 °C, the growth appears columnar, indicating nucleation controlled growth. Elevated deposition temperatures, on the other hand, render the CoSi2 formation process layer-by-layer which indicates enhanced nucleation of the CoSi2 and diffusion controlled growth. Our results further indicate that this observed trend is most likely related to stress and changes in microstructure introduced during reactive deposition of the CoSi film. The deposition temperature therefore provides a handle to tune the CoSi2 growth mechanism. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000321011700077 |
Publication Date |
2013-06-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
2 |
Open Access |
|
Notes |
Fwo; Countatoms |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2013 IF: 2.185 |
Call Number |
UA @ lucian @ c:irua:109266 |
Serial |
815 |
Permanent link to this record |
|
|
|
Author |
Milovanovic, S.P.; Masir, M.R.; Peeters, F.M. |
Title |
Graphene hall bar with an asymmetric pn-junction |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
113 |
Issue |
19 |
Pages |
193701-193708 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigated the magnetic field dependence of the Hall and the bend resistances in the ballistic regime for a single layer graphene Hall bar structure containing a pn-junction. When both regions are n-type the Hall resistance dominates and Hall type of plateaus are formed. These plateaus occur as a consequence of the restriction on the angle imposed by Snell's law allowing only electrons with a certain initial angles to transmit though the potential step. The size of the plateau and its position is determined by the position of the potential interface as well as the value of the applied potential. When the second region is p-type, the bend resistance dominates, which is asymmetric in field due to the presence of snake states. Changing the position of the pn-interface in the Hall bar strongly affects these states and therefore the bend resistance is also changed. Changing the applied potential, we observe that the bend resistance exhibits a peak around the charge-neutrality point (CNP), which is independent of the position of the pn-interface, while the Hall resistance shows a sign reversal when the CNP is crossed, which is in very good agreement with a recent experiment [J. R. Williams and C. M. Marcus, Phys. Rev. Lett. 107, 046602 (2011)]. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000319295200022 |
Publication Date |
2013-05-16 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
7 |
Open Access |
|
Notes |
This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN, and the Methusalem Foundation of the Flemish government. We acknowledge fruitful discussions with M. Barbier. |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2013 IF: 2.185 |
Call Number |
UA @ lucian @ c:irua:108999 |
Serial |
1371 |
Permanent link to this record |
|
|
|
Author |
Shapoval, O.; Huehn, S.; Verbeeck, J.; Jungbauer, M.; Belenchuk, A.; Moshnyaga, V. |
Title |
Interface-controlled magnetism and transport of ultrathin manganite films |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
113 |
Issue |
17 |
Pages |
17c711-3 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
We report ferromagnetic, T-C = 240 K, and metallic, T-MI = 250 K, behaviors of a three unit cell thick interface engineered lanthanum manganite film, grown by metalorganic aerosol deposition technique on SrTiO3(100) substrates. Atomically resolved electron microscopy and chemical analysis show that ultrathin manganite films start to grow with La-O layer on a strongly Mn/Ti-intermixed interface, engineered by an additional deposition of 2 u.c. of Sr-Mn-O. Such interface engineering results in a hole-doped manganite layer and stabilizes ferromagnetism and metallic conductivity down to the thickness of d = 3 u.c. The films with d = 8 u.c. demonstrate a bulk-like transport behavior with T-MI similar to T-C = 310 – 330 K. (C) 2013 American Institute of Physics. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000319292800195 |
Publication Date |
2013-03-19 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
7 |
Open Access |
|
Notes |
Ifox; Countatoms; Vortex; Esteem2; esteem2jra3 ECASJO; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2013 IF: 2.185 |
Call Number |
UA @ lucian @ c:irua:109009UA @ admin @ c:irua:109009 |
Serial |
1692 |
Permanent link to this record |
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|
|
Author |
Maignan, A.; Singh, K.; Simon, C.; Lebedev, O.I.; Martin, C.; Tan, H.; Verbeeck, J.; Van Tendeloo, G. |
Title |
Magnetic and magnetodielectric properties of erbium iron garnet ceramic |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
113 |
Issue |
3 |
Pages |
033905-5 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
An Er3Fe5O12 ceramic has been sintered in oxygen atmosphere at 1400 °C for dielectric measurements. Its structural quality at room temperature has been checked by combining transmission electron microscopy and X-ray diffraction. It crystallizes in the cubic space group Ia3d with a = 12.3488(1). The dielectric permittivity ([variantgreekepsilon]′) and losses (tan δ) measurements as a function of temperature reveal the existence of two anomalies, a broad one between 110 K and 80 K, attributed to the Er3+ spin reorientation, and a second sharper feature at about 45 K associated to the appearance of irreversibility on the magnetic susceptibility curves. In contrast to the lack of magnetic field impact on [variantgreekepsilon]′ for the former anomaly, a complex magnetic field effect has been evidenced below 45 K. The isothermal [variantgreekepsilon]′(H) curves show the existence of positive magnetodielectric effect, reaching a maximum of 0.14% at 3 T and 10 K. Its magnitude decreases as H is further increased. Interestingly, for the lowest H values, a linear regime in the [variantgreekepsilon]′(H) curve is observed. From this experimental study, it is concluded that the [variantgreekepsilon]′ anomaly, starting above the compensation temperature Tc (75 K) and driven by the internal magnetic field, is not sensitive to an applied external magnetic field. Thus, below 45 K, it is the magnetic structure which is responsible for the coupling between spin and charge in this iron garnet. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000313670600042 |
Publication Date |
2013-01-16 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
15 |
Open Access |
|
Notes |
Vortex; Countatoms ECASJO_; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2013 IF: 2.185 |
Call Number |
UA @ lucian @ c:irua:106182UA @ admin @ c:irua:106182 |
Serial |
1861 |
Permanent link to this record |
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|
|
Author |
Carrillo-Nuñez, H.; Magnus, W.; Vandenberghe, W.G.; Sorée, B.; Peeters, F.M. |
Title |
Phonon-assisted Zener tunneling in a cylindrical nanowire transistor |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
113 |
Issue |
18 |
Pages |
184507-184508 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The tunneling current has been computed for a cylindrical nanowire tunneling field-effect transistor (TFET) with an all-round gate that covers the source region. Being the underlying mechanism, band-to-band tunneling, mediated by electron-phonon interaction, is pronouncedly affected by carrier confinement in the radial direction and, therefore, involves the self-consistent solution of the Schrodinger and Poisson equations. The latter has been accomplished by exploiting a non-linear variational principle within the framework of the modified local density approximation taking into account the nonparabolicity of both the valence band and conduction band in relatively thick wires. Moreover, while the effective-mass approximation might still provide a reasonable description of the conduction band in relatively thick wires, we have found that the nonparabolicity of the valence band needs to be included. As a major conclusion, it is observed that confinement effects in nanowire tunneling field-effect transistors have a stronger impact on the onset voltage of the tunneling current in comparison with planar TFETs. On the other hand, the value of the onset voltage is found to be overestimated when the valence band nonparabolicity is ignored. (C) 2013 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000319294100093 |
Publication Date |
2013-05-10 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
4 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI), and the Interuniversity Attraction Poles, Belgium State, Belgium Science Policy, and IMEC. ; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2013 IF: 2.185 |
Call Number |
UA @ lucian @ c:irua:109651 |
Serial |
2599 |
Permanent link to this record |
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|
|
Author |
Autrique, D.; Clair, G.; L'Hermite, D.; Alexiades, V.; Bogaerts, A.; Rethfeld, B. |
Title |
The role of mass removal mechanisms in the onset of ns-laser induced plasma formation |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
114 |
Issue |
2 |
Pages |
023301-23310 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
The present study focuses on the role of mass removal mechanisms in ns-laser ablation. A copper sample is placed in argon, initially set at standard pressure and temperature. Calculations are performed for a 6 ns laser pulse with a wavelength of 532 nm and laser fluences up to 10 J/cm2. The transient behavior in and above the copper target is described by a hydrodynamic model. Transmission profiles and ablation depths are compared with experimental results and similar trends are found. Our calculations reveal an interesting self-inhibiting mechanism: volumetric mass removal in the supercritical region triggers plasma shielding and therefore stops proceeding. This self-limiting process indicates that volumetric mass removal does not necessarily result in large ablation depths. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000321761600006 |
Publication Date |
2013-07-08 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
31 |
Open Access |
|
Notes |
|
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2013 IF: 2.185 |
Call Number |
UA @ lucian @ c:irua:109237 |
Serial |
2915 |
Permanent link to this record |
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Author |
Shestakov, M.V.; Meledina, M.; Turner, S.; Tikhomirov, V.K.; Verellen, N.; Rodríguez, V.D.; Velázquez, J.J.; Van Tendeloo, G.; Moshchalkov, V.V. |
Title |
The size and structure of Ag particles responsible for surface plasmon effects and luminescence in Ag homogeneously doped bulk glass |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
114 |
Issue |
7 |
Pages |
073102-73105 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
As-prepared and heat-treated oxyfluoride glasses, co-doped with Ag nanoclusters/nanoparticles, are prepared at 0.15 at. % Ag concentration. The as-prepared glass shows an absorption band in the UV/violet attributed to the presence of amorphous Ag nanoclusters with an average size of 1.1 nm. The luminescence spectra of the untreated glass can also be ascribed to these Ag nanoclusters. Upon heat-treatment, the clusters coalesce into Ag nanoparticles with an average size of 2.3 nm, and the glasses show an extra surface plasmon absorption band in the visible. These particles, however, cease to emit due to ascribing plasmonic properties of bulk silver. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000323510900003 |
Publication Date |
2013-08-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
19 |
Open Access |
|
Notes |
Fwo |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2013 IF: 2.185 |
Call Number |
UA @ lucian @ c:irua:109455 |
Serial |
3031 |
Permanent link to this record |
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|
Author |
Salman, O.U.; Finel, A.; Delville, R.; Schryvers, D. |
Title |
The role of phase compatibility in martensite |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of applied physics
T2 – 22nd International Symposium on Integrated Functionalities (ISIF), JUN 13-16, 2010, San Juan, PR |
Abbreviated Journal |
J Appl Phys |
Volume |
111 |
Issue |
10 |
Pages |
103517 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Shape memory alloys inherit their macroscopic properties from their mesoscale microstructure originated from the martensitic phase transformation. In a cubic to orthorhombic transition, a single variant of martensite can have a compatible (exact) interface with the austenite for some special lattice parameters in contrast to conventional austenite/twinned martensite interface with a transition layer. Experimentally, the phase compatibility results in a dramatic drop in thermal hysteresis and gives rise to very stable functional properties over cycling. Here, we investigate the microstructures observed in Ti50Ni50-xPdx alloys that undergo a cubic to orthorhombic martensitic transformation using a three-dimensional phase field approach. We will show that the simulation results are in very good agreement with transmission electron microscopy observations. However, the understanding of the drop in thermal hysteresis requires the coupling of phase transformation with plastic activity. We will discuss this point within the framework of thermoelasticity, which is a generic feature of the martensitic transformation. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4712629] |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
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Wos |
000305363700053 |
Publication Date |
2012-05-21 |
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 |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
11 |
Open Access |
|
Notes |
|
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2012 IF: 2.210 |
Call Number |
UA @ lucian @ c:irua:100310 |
Serial |
2919 |
Permanent link to this record |
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|
|
Author |
Wendelen, W.; Mueller, B.Y.; Autrique, D.; Rethfeld, B.; Bogaerts, A. |
Title |
Space charge corrected electron emission from an aluminum surface under non-equilibrium conditions |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
111 |
Issue |
11 |
Pages |
113110 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
A theoretical study has been conducted of ultrashort pulsed laser induced electron emission from an aluminum surface. Electron emission fluxes retrieved from the commonly employed Fowler-DuBridge theory were compared to fluxes based on a laser-induced non-equilibrium electron distribution. As a result, the two-and three-photon photoelectron emission parameters for the Fowler-DuBridge theory have been approximated. We observe that at regimes where photoemission is important, laser-induced electron emission evolves in a more smooth manner than predicted by the Fowler-DuBridge theory. The importance of the actual electron distribution decreases at higher laser fluences, whereas the contribution of thermionic emission increases. Furthermore, the influence of a space charge effect on electron emission was evaluated by a one dimensional particle-in-cell model. Depending on the fluences, the space charge reduces the electron emission by several orders of magnitude. The influence of the electron emission flux profiles on the effective electron emission was found to be negligible. However, a non-equilibrium electron velocity distribution increases the effective electron emission significantly. Our results show that it is essential to consider the non-equilibrium electron distribution as well as the space charge effect for the description of laser-induced photoemission. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4729071] |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000305401400043 |
Publication Date |
2012-06-14 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
30 |
Open Access |
|
Notes |
|
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2012 IF: 2.210 |
Call Number |
UA @ lucian @ c:irua:100300 |
Serial |
3057 |
Permanent link to this record |
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Author |
de Sousa, J.S.; Covaci, L.; Peeters, F.M.; Farias, G.A. |
Title |
Time-dependent investigation of charge injection in a quantum dot containing one electron |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
112 |
Issue |
9 |
Pages |
093705-93709 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The interaction of an injected electron towards a quantum dot (QD) containing a single confined electron is investigated using a flexible time-dependent quantum mechanics formalism, which allows both electrons to move and undergo quantum transitions. Different scenarios combining quantum dot dimensions, dielectric constant, injected wave packet energy, and width were explored, and our main results are: (i) due to the large characteristic transitions times between the confined state in the quantum dot and the delocalized state in the continuum, it is relatively difficult to ionize the occupied QD by Coulomb interaction solely and (ii) the charging state of the quantum dot can be sensed by direct injection of charges. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4759292] |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
Language |
|
Wos |
000311968400052 |
Publication Date |
2012-11-06 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
1 |
Open Access |
|
Notes |
; This work was financially supported by the Brazilian National Research Council (CNPq), under Contract No. NanoBioEstruturas 555183/2005-0, Fundao Cearense de Apoio ao Desenvolvimento Cientfico e Tecnolgico (Funcap), CAPES, Pronex/CNPq/ Funcap, the Bilateral program between Flanders and Brazil, and the Flemish Science Foundation (FWO). ; |
Approved ![sorted by Approved field, descending order (down)](img/sort_desc.gif) |
Most recent IF: 2.068; 2012 IF: 2.210 |
Call Number |
UA @ lucian @ c:irua:106014 |
Serial |
3664 |
Permanent link to this record |