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Author |
Van de Put, M.; Thewissen, M.; Magnus, W.; Sorée, B.; Sellier, J.M. |
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Title |
Spectral force approach to solve the time-dependent Wigner-Liouville equation |
Type |
P1 Proceeding |
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Year |
2014 |
Publication |
2014 International Workshop On Computational Electronics (iwce) |
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Issue |
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Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
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Corporate Author |
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Thesis |
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Publisher |
Ieee |
Place of Publication |
New york |
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Wos |
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Publication Date |
0000-00-00 |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
978-1-4799-5433-9 |
ISBN |
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Additional Links |
UA library record; WoS full record; |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:122221 |
Serial |
3071 |
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Permanent link to this record |
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Author |
Carrillo-Nuñez, H.; Magnus, W.; Vandenberghe, W.G.; Sorée, B.; Peeters, F.M. |
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Title |
Phonon-assisted Zener tunneling in a cylindrical nanowire transistor |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
113 |
Issue |
18 |
Pages |
184507-184508 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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. |
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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 |
000319294100093 |
Publication Date |
2013-05-10 |
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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 |
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ISSN |
0021-8979; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
4 |
Open Access |
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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 |
Most recent IF: 2.068; 2013 IF: 2.185 |
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Call Number |
UA @ lucian @ c:irua:109651 |
Serial |
2599 |
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Permanent link to this record |
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Author |
Vandenberghe, W.G.; Verhulst, A.S.; Sorée, B.; Magnus, W.; Groeseneken, G.; Smets, Q.; Heyns, M.; Fischetti, M.V. |
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Title |
Figure of merit for and identification of sub-60 mV/decade devices |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
102 |
Issue |
1 |
Pages |
013510-13514 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
A figure of merit I60 is proposed for sub-60 mV/decade devices as the highest current where the input characteristics exhibit a transition from sub- to super-60 mV/decade behavior. For sub-60 mV/decade devices to be competitive with metal-oxide-semiconductor field-effect devices, I60 has to be in the 1-10 μA/μm range. The best experimental tunnel field-effect transistors (TFETs) in the literature only have an I60 of 6×10-3 μA/μm but using theoretical simulations, we show that an I60 of up to 10 μA/μm should be attainable. It is proven that the Schottky barrier FET (SBFET) has a 60 mV/decade subthreshold swing limit while combining a SBFET and a TFET does improve performance. |
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Corporate Author |
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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 |
000313646500132 |
Publication Date |
2013-01-12 |
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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 |
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ISSN |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
64 |
Open Access |
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Notes |
; William G. Vandenberghe gratefully acknowledges the support of a Ph.D. stipend from IWT-Vlaanderen. The authors thank Danielle Leonelli, Lars-Ake Ragnarsson, and Krishna Bhuwalka for useful discussions. This work was supported by imec's Industrial Affiliation Program. ; |
Approved |
Most recent IF: 3.411; 2013 IF: 3.515 |
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Call Number |
UA @ lucian @ c:irua:109262 |
Serial |
1192 |
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Permanent link to this record |
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Author |
Carrillo-Nunez, H.; Magnus, W.; Vandenberghe, W.G.; Sorée, B.; Peeters, F.M. |
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Title |
Phonon-assisted Zener tunneling in a p-n diode silicon nanowire |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Solid state electronics |
Abbreviated Journal |
Solid State Electron |
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Volume |
79 |
Issue |
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Pages |
196-200 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The Zener tunneling current flowing through a biased, abrupt p-n junction embedded in a cylindrical silicon nanowire is calculated. As the band gap becomes indirect for sufficiently thick wires, Zener tunneling and its related transitions between the valence and conduction bands are mediated by short-wavelength phonons interacting with mobile electrons. Therefore, not only the high electric field governing the electrons in the space-charge region but also the transverse acoustic (TA) and transverse optical (TO) phonons have to be incorporated in the expression for the tunneling current. The latter is also affected by carrier confinement in the radial direction and therefore we have solved the Schrodinger and Poisson equations self-consistently within the effective mass approximation for both conduction and valence band electrons. We predict that the tunneling current exhibits a pronounced dependence on the wire radius, particularly in the high-bias regime. (C) 2012 Elsevier Ltd. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000313611000037 |
Publication Date |
2012-09-29 |
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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 |
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ISSN |
0038-1101; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.58 |
Times cited |
2 |
Open Access |
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Notes |
; This work is supported by the Flemish Science Foundation (FWO-VI), and the Interuniversity Attraction Poles, Belgium State, Belgium Science Policy, and IMEC. One of the authors (W. Vandenberghe) gratefully acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). ; |
Approved |
Most recent IF: 1.58; 2013 IF: 1.514 |
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Call Number |
UA @ lucian @ c:irua:110104 |
Serial |
2600 |
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Permanent link to this record |
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Author |
Sels, D.; Brosens, F.; Magnus, W. |
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Title |
Wigner distribution functions for complex dynamical systems : a path integral approach |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Physica: A : theoretical and statistical physics |
Abbreviated Journal |
Physica A |
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Volume |
392 |
Issue |
2 |
Pages |
326-335 |
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Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) |
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Abstract |
Starting from Feynmans Lagrangian description of quantum mechanics, we propose a method to construct explicitly the propagator for the Wigner distribution function of a single system. For general quadratic Lagrangians, only the classical phase space trajectory is found to contribute to the propagator. Inspired by Feynmans and Vernons influence functional theory we extend the method to calculate the propagator for the reduced Wigner function of a system of interest coupled to an external system. Explicit expressions are obtained when the external system consists of a set of independent harmonic oscillators. As an example we calculate the propagator for the reduced Wigner function associated with the CaldeiraLegett model. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000311135200004 |
Publication Date |
2012-09-14 |
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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 |
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ISSN |
0378-4371; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.243 |
Times cited |
9 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 2.243; 2013 IF: 1.722 |
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Call Number |
UA @ lucian @ c:irua:101414 |
Serial |
3921 |
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Permanent link to this record |
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Author |
Kao, K.-H.; Verhulst, A.S.; Vandenberghe, W.G.; Sorée, B.; Magnus, W.; Leonelli, D.; Groeseneken, G.; De Meyer, K. |
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Title |
Optimization of gate-on-source-only tunnel FETs with counter-doped pockets |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
IEEE transactions on electron devices |
Abbreviated Journal |
Ieee T Electron Dev |
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Volume |
59 |
Issue |
8 |
Pages |
2070-2077 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We investigate a promising tunnel FET configuration having a gate on the source only, which is simultaneously exhibiting a steeper subthreshold slope and a higher ON-current than the lateral tunneling configuration with a gate on the channel. Our analysis is performed based on a recently developed 2-D quantum-mechanical simulator calculating band-to-band tunneling and including quantum confinement (QC). It is shown that the two disadvantages of the structure, namely, the sensitivity to gate alignment and the physical oxide thickness, are mitigated by placing a counter-doped parallel pocket underneath the gate-source overlap. The pocket also significantly reduces the field-induced QC. The findings are illustrated with all-Si and all-Ge gate-on-source-only tunnel field-effect transistor simulations. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000306920200011 |
Publication Date |
2012-06-27 |
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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 |
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ISSN |
0018-9383;1557-9646; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.605 |
Times cited |
72 |
Open Access |
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Notes |
; Manuscript received February 17, 2012; revised May 7, 2012; accepted May 11, 2012. Date of publication June 26, 2012; date of current version July 19, 2012. This work was supported by the Interuniversity Microelectronics Center's Industrial Affiliation Program. The work of W. G. Vandenberghe was supported by the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen) through a Ph.D. stipend. The review of this paper was arranged by Editor H. S. Momose. ; |
Approved |
Most recent IF: 2.605; 2012 IF: 2.062 |
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Call Number |
UA @ lucian @ c:irua:100820 |
Serial |
2487 |
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Permanent link to this record |
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Author |
Vandenberghe, W.G.; Verhulst, A.S.; Kao, K.-H.; De Meyer, K.; Sorée, B.; Magnus, W.; Groeseneken, G. |
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Title |
A model determining optimal doping concentration and material's band gap of tunnel field-effect transistors |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
100 |
Issue |
19 |
Pages |
193509-193509,4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We develop a model for the tunnel field-effect transistor (TFET) based on the Wentzel-Kramer-Brillouin approximation which improves over existing semi-classical models employing generation rates. We hereby introduce the concept of a characteristic tunneling length in direct semiconductors. Based on the model, we show that a limited density of states results in an optimal doping concentration as well as an optimal material's band gap to obtain the highest TFET on-current at a given supply voltage. The observed optimal-doping trend is confirmed by 2-dimensional quantum-mechanical simulations for silicon and germanium. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4714544] |
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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 |
000304108000098 |
Publication Date |
2012-05-12 |
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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 |
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ISSN |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
25 |
Open Access |
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Notes |
; William Vandenberghe gratefully acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). This work was supported by IMEC's Industrial Affiliation Program. ; |
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
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Call Number |
UA @ lucian @ c:irua:98948 |
Serial |
2105 |
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Permanent link to this record |
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Author |
Sels, D.; Brosens, F.; Magnus, W. |
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Title |
On the path integral representation of the Wigner function and the BarkerMurray ansatz |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physics letters : A |
Abbreviated Journal |
Phys Lett A |
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Volume |
376 |
Issue |
6/7 |
Pages |
809-812 |
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Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) |
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Abstract |
The propagator of the Wigner function is constructed from the WignerLiouville equation as a phase space path integral over a new effective Lagrangian. In contrast to a paper by Barker and Murray (1983) [1], we show that the path integral can in general not be written as a linear superposition of classical phase space trajectories over a family of non-local forces. Instead, we adopt a saddle point expansion to show that the semiclassical Wigner function is a linear superposition of classical solutions for a different set of non-local time dependent forces. As shown by a simple example the specific form of the path integral makes the formulation ideal for Monte Carlo simulation. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000301167300005 |
Publication Date |
2012-01-17 |
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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 |
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ISSN |
0375-9601; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.772 |
Times cited |
7 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 1.772; 2012 IF: 1.766 |
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Call Number |
UA @ lucian @ c:irua:94006 |
Serial |
2445 |
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Permanent link to this record |
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Author |
Pham, A.-T.; Sorée, B.; Magnus, W.; Jungemann, C.; Meinerzhagen, B.; Pourtois, G. |
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Title |
Quantum simulations of electrostatics in Si cylindrical junctionless nanowire nFETs and pFETs with a homogeneous channel including strain and arbitrary crystallographic orientations |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Solid state electronics |
Abbreviated Journal |
Solid State Electron |
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Volume |
71 |
Issue |
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Pages |
30-36 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Simulation results of electrostatics in Si cylindrical junctionless nanowire transistors with a homogenous channel are presented. Junctionless transistors including strain and arbitrary crystallographic orientations are studied. Size quantization effects are simulated by self-consistent solutions of the Poisson and Schrodinger equations. The 6 x 6 k.p method is employed for the calculation of the valence subband structure in a junctionless nanowire pFET. The influence of stress/strain and crystallographic channel orientation on to the electrostatics in terms of subband structure, charge density, and C-V curve is systematically studied. (C) 2011 Elsevier Ltd. All rights reserved. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
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Language |
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Wos |
000303033800007 |
Publication Date |
2011-12-01 |
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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 |
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ISSN |
0038-1101; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.58 |
Times cited |
2 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 1.58; 2012 IF: 1.482 |
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Call Number |
UA @ lucian @ c:irua:98245 |
Serial |
2786 |
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Permanent link to this record |
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Author |
Sels, D.; Brosens, F.; Magnus, W. |
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Title |
Classical trajectories : a powerful tool for solving tunneling problems |
Type |
A1 Journal article |
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Year |
2012 |
Publication |
Physica: A : theoretical and statistical physics |
Abbreviated Journal |
Physica A |
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Volume |
391 |
Issue |
1/2 |
Pages |
78-81 |
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Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) |
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Abstract |
In the realm of Ehrenfests theorem, classical trajectories obeying Newtons laws have been proven useful to construct explicit solutions to the time-dependent WignerLiouville equation. Whereas previous works have particularly focused on the initial distribution function as a vehicle found to carry the signatures of quantum statistics into the time-dependent solution, the present paper shows that the LagrangeCharpit method based on classical trajectories can be successfully invoked as well to tackle quantum mechanical features with no classical counterpart, such as tunneling. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000297230700010 |
Publication Date |
2011-08-25 |
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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 |
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ISSN |
0378-4371; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.243 |
Times cited |
7 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 2.243; 2012 IF: 1.676 |
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Call Number |
UA @ lucian @ c:irua:92359 |
Serial |
370 |
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Permanent link to this record |
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Author |
Sorée, B.; Magnus, W.; Vandenberghe, W. |
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Title |
Low-field mobility in ultrathin silicon nanowire junctionless transistors |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
99 |
Issue |
23 |
Pages |
233509-233509,3 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We theoretically investigate the phonon, surface roughness and ionized impurity limited low-field mobility of ultrathin silicon n-type nanowire junctionless transistors in the long channel approximation with wire radii ranging from 2 to 5 nm, as function of gate voltage. We show that surface roughness scattering is negligible as long as the wire radius is not too small and ionized impurity scattering is the dominant scattering mechanism. We also show that there exists an optimal radius where the ionized impurity limited mobility exhibits a maximum. |
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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 |
000298006100095 |
Publication Date |
2011-12-09 |
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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 |
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ISSN |
0003-6951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
20 |
Open Access |
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Notes |
; This work is supported by the EU project SQWIRE (FP7-ICT-STREP nr. 257111). William Vandenberghe gratefully acknowledges the Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). ; |
Approved |
Most recent IF: 3.411; 2011 IF: 3.844 |
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Call Number |
UA @ lucian @ c:irua:92865 |
Serial |
1850 |
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Permanent link to this record |
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Author |
Vandenberghe, W.; Sorée, B.; Magnus, W.; Fischetti, M.V. |
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Title |
Generalized phonon-assisted Zener tunneling in indirect semiconductors with non-uniform electric fields : a rigorous approach |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
109 |
Issue |
12 |
Pages |
124503-124503,12 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
A general framework to calculate the Zener current in an indirect semiconductor with an externally applied potential is provided. Assuming a parabolic valence and conduction band dispersion, the semiconductor is in equilibrium in the presence of the external field as long as the electron-phonon interaction is absent. The linear response to the electron-phonon interaction results in a non-equilibrium system. The Zener tunneling current is calculated from the number of electrons making the transition from valence to conduction band per unit time. A convenient expression based on the single particle spectral functions is provided, enabling the evaluation of the Zener tunneling current under any three-dimensional potential profile. For a one-dimensional potential profile an analytical expression is obtained for the current in a bulk semiconductor, a semiconductor under uniform field, and a semiconductor under a non-uniform field using the WKB (Wentzel-Kramers-Brillouin) approximation. The obtained results agree with the Kane result in the low field limit. A numerical example for abrupt p-n diodes with different doping concentrations is given, from which it can be seen that the uniform field model is a better approximation than the WKB model, but a direct numerical treatment is required for low bias conditions. |
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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 |
000292331200134 |
Publication Date |
2011-06-21 |
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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 |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.068 |
Times cited |
41 |
Open Access |
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|
Notes |
; William Vandenberghe gratefully acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). ; |
Approved |
Most recent IF: 2.068; 2011 IF: 2.168 |
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|
Call Number |
UA @ lucian @ c:irua:90808 |
Serial |
1325 |
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Permanent link to this record |
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Author |
Vandenberghe, W.G.; Sorée, B.; Magnus, W.; Groeseneken, G.; Fischetti, M.V. |
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Title |
Impact of field-induced quantum confinement in tunneling field-effect devices |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
|
|
Volume |
98 |
Issue |
14 |
Pages |
143503,1-143503,3 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Being the working principle of a tunnel field-effect transistor, band-to-band tunneling is given a rigorous quantum mechanical treatment to incorporate confinement effects, multiple electron and hole valleys, and interactions with phonons. The model reveals that the strong band bending near the gate dielectric, required to create short tunnel paths, results in quantization of the energy bands. Comparison with semiclassical models reveals a big shift in the onset of tunneling. The effective mass difference of the distinct valleys is found to reduce the subthreshold swing steepness. |
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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 |
000289297800074 |
Publication Date |
2011-04-06 |
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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 |
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ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.411 |
Times cited |
76 |
Open Access |
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Notes |
; The authors acknowledge Anne Verhulst for useful discussions. William Vandenberghe gratefully acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). This work was supported by IMEC's Industrial Affiliation Program. ; |
Approved |
Most recent IF: 3.411; 2011 IF: 3.844 |
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Call Number |
UA @ lucian @ c:irua:89297 |
Serial |
1559 |
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Permanent link to this record |
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Author |
Sorée, B.; Pham, A.-T.; Sels, D.; Magnus, W. |
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Title |
The junctionless nanowire transistor |
Type |
H3 Book chapter |
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Year |
2011 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
? |
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Keywords |
H3 Book chapter; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Pan Stanford |
Place of Publication |
S.l. |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
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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 |
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ISSN |
|
ISBN |
9789814364027 |
Additional Links |
UA library record |
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Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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|
Call Number |
UA @ lucian @ c:irua:93074 |
Serial |
1754 |
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Permanent link to this record |
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Author |
Magnus, W.; Carrillo-Nunez, H.; Sorée, B. |
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Title |
Transport in nanostructures |
Type |
H3 Book chapter |
|
Year |
2011 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
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Keywords |
H3 Book chapter; Condensed Matter Theory (CMT) |
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Abstract |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Pan Stanford |
Place of Publication |
S.l. |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
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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 |
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ISSN |
|
ISBN |
9789814364027 |
Additional Links |
UA library record |
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Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:93075 |
Serial |
3724 |
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Permanent link to this record |
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Author |
Carrillo-Nuñez, H.; Magnus, W.; Peeters, F.M. |
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Title |
A simplified quantum mechanical model for nanowire transistors based on non-linear variational calculus |
Type |
A1 Journal article |
|
Year |
2010 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
|
|
Volume |
108 |
Issue |
6 |
Pages |
063708,1-063708,8 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
A simplified quantum mechanical model is developed to investigate quantum transport features such as the electron concentration and the current flowing through a silicon nanowire metal-oxide-semiconductor field-effect transistor (MOSFET). In particular, the electron concentration is extracted from a self-consistent solution of the Schrödinger and Poisson equations as well as the ballistic Boltzmann equation which have been solved by exploiting a nonlinear variational principle within the framework of the generalized local density approximation. A suitable action functional has been minimized and details of the implementation and its numerical minimization are given. The current density and its related current-voltage characteristics are calculated from the one-dimensional ballistic steady-state Boltzmann transport equation which is solved analytically by using the method of characteristic curves. The straightforward implementation, the computational speed and the good qualitative behavior of the transport characteristics observed in our approach make it a promising simulation method for modeling quantum transport in nanowire MOSFETs. |
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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 |
000282646400067 |
Publication Date |
2010-09-22 |
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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 |
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|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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|
Impact Factor |
2.068 |
Times cited |
7 |
Open Access |
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|
Notes |
; This work was supported by Flemish Science Foundation (FWO-VI) and the Interuniversity Attraction Poles, Belgium State, Belgium Science Policy, and IMEC. ; |
Approved |
Most recent IF: 2.068; 2010 IF: 2.079 |
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Call Number |
UA @ lucian @ c:irua:84943 |
Serial |
3006 |
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Permanent link to this record |
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Author |
Brosens, F.; Magnus, W. |
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Title |
Newtonian trajectories : a powerful tool for solving quantum dynamics |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Solid state communications |
Abbreviated Journal |
Solid State Commun |
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Volume |
150 |
Issue |
43/44 |
Pages |
2102-2105 |
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Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) |
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Abstract |
Since Ehrenfests theorem, the role and importance of classical paths in quantum dynamics have been examined by several means. Along this line, we show that the classical equations of motion provide a solution to quantum dynamics, if appropriately incorporated into the Wigner distribution function, exactly reformulated in a type of Boltzmann equation. Also the quantum-mechanical features of the canonical ensemble can be studied in this framework of Newtonian dynamics, if the initial distribution function is appropriately constructed from the statistical operator. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000284251700006 |
Publication Date |
2010-09-20 |
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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 |
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ISSN |
0038-1098; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.554 |
Times cited |
7 |
Open Access |
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Notes |
; The authors thank J.T. Devreese and J. Tempere for interesting and helpful discussions, and, in particular, L.F. Lemmens for several valuable suggestions. One of the authors (F.B.) acknowledges the FWO projects G.0115.06 and G.0365.08 as well as the WOG project WO.033.09N, for financial support. ; |
Approved |
Most recent IF: 1.554; 2010 IF: 1.981 |
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Call Number |
UA @ lucian @ c:irua:85795 |
Serial |
2338 |
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Permanent link to this record |
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Author |
Vandenberghe, W.; Sorée, B.; Magnus, W.; Groeseneken, G. |
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Title |
Zener tunneling in semiconductors under nonuniform electric fields |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
107 |
Issue |
5 |
Pages |
054520,1-054520,7 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Recently, a renewed interest in Zener tunneling has arisen because of its increasing impact on semiconductor device performance at nanometer dimensions. In this paper we evaluate the tunnel probability under the action of a nonuniform electric field using a two-band model and arrive at significant deviations from the commonly used Kanes model, valid for weak uniform fields only. A threshold on the junction bias where Kanes model for Zener tunneling breaks down is determined. Comparison with Kanes model particularly shows that our calculation yields a higher tunnel probability for intermediate electric fields and a lower tunnel probability for high electric fields. When performing a current calculation comparing to the WKB approximation for the case of an abrupt p-n junction significant differences concerning the shape of the I-V curve are demonstrated. |
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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 |
000275657500136 |
Publication Date |
2010-03-11 |
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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 |
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ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
22 |
Open Access |
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|
Notes |
; William Vandenberghe gratefully acknowledges the support of a Ph. D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). These authors acknowledge the support from IMEC's Industrial Affiliation Program and the authors would like to thank Anne Verhulst for useful comments. ; |
Approved |
Most recent IF: 2.068; 2010 IF: 2.079 |
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Call Number |
UA @ lucian @ c:irua:82450 |
Serial |
3929 |
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Permanent link to this record |
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Author |
Li, B.; Magnus, W.; Peeters, F.M. |
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Title |
Tunable exciton Aharonov-Bohm effect in a quantum ring |
Type |
A1 Journal article |
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Year |
2010 |
Publication |
Journal of physics : conference series
T2 – Proceedings of the 11th International Conference on Optics of Excitons in Confined Systems, September 7-11, 2009, Spain / Vina, L. [edit.]; et al. [edit.] |
Abbreviated Journal |
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Volume |
210 |
Issue |
1 |
Pages |
012030,1-01203,4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We studied the optical Aharonov-Bohm effect for an exciton in a semiconductor quantum ring. A perpendicular electric field applied to a quantum ring with large height, is able to tune the exciton ground state energy such that it exhibits a weak observable Aharonov-Bohm oscillations. This Aharonov-Bohm effect is tunable in strength and period. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000289715800242 |
Publication Date |
2010-03-03 |
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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 |
|
Series Issue |
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Edition |
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ISSN |
1742-6596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
3 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:89950 |
Serial |
3741 |
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Permanent link to this record |
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Author |
Sorée, B.; Magnus, W.; Szepieniec, M.; Vandenbreghe, W.; Verhulst, A.; Pourtois, G.; Groeseneken, G.; de Gendt, S.; Heyns, M. |
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Title |
Novel device concepts for nanotechnology : the nanowire pinch-off FET and graphene tunnelFET |
Type |
A2 Journal article |
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Year |
2010 |
Publication |
ECS transactions |
Abbreviated Journal |
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Volume |
28 |
Issue |
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Pages |
15-26 |
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Keywords |
A2 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
We explain the basic operation of a nanowire pinch-off FET and graphene nanoribbon tunnelFET. For the nanowire pinch-off FET we construct an analytical model to obtain the threshold voltage as a function of radius and doping density. We use the gradual channel approximation to calculate the current-voltage characteristics of this device and we show that the nanowire pinch-off FET has a subthreshold slope of 60 mV/dec and good ION and ION/IOFF ratios. For the graphene nanoribbon tunnelFET we show that an improved analytical model yields more realistic results for the transmission probability and hence the tunneling current. The first simulation results for the graphene nanoribbon tunnelFET show promising subthreshold slopes. |
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Corporate Author |
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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 |
0000-00-00 |
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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 |
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ISSN |
1938-5862 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:89510 |
Serial |
2375 |
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Permanent link to this record |
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Author |
Carrillo-Nuñez, H.; Magnus, W.; Peeters, F.M. |
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Title |
A non-linear variational principle for the self-consistent solution of Poisson's equation and a transport equation in the local density approximation |
Type |
P1 Proceeding |
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Year |
2010 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
171-174 |
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Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
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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 |
New York, N.Y. |
Editor |
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Language |
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Wos |
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Publication Date |
0000-00-00 |
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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 |
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ISSN |
978-1-4244-7699-2 |
ISBN |
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Additional Links |
UA library record; WoS full record; |
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Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:85824 |
Serial |
2347 |
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Permanent link to this record |
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Author |
Magnus, W.; Brosens, F.; Sorée, B. |
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Title |
Time dependent transport in 1D micro- and nanostructures: solving the Boltzmann and Wigner-Boltzmann equations |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of physics : conference series |
Abbreviated Journal |
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Volume |
193 |
Issue |
1 |
Pages |
012004,1-012004,4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
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Abstract |
For many decades the Boltzmann distribution function has been used to calculate the non-equilibrium properties of mobile particles undergoing the combined action of various scattering mechanisms and externally applied force fields. When the latter give rise to the occurrence of inhomogeneous potential profiles across the region through which the particles are moving, the numerical solution of the Boltzmann equation becomes a highly complicated task. In this work we highlight a particular algorithm that can be used to solve the time dependent Boltzmann equation as well as its quantum mechanical extension, the WignerBoltzmann equation. As an illustration, we show the calculated distribution function describing electrons propagating under the action of both a uniform and a pronouncedly non-uniform electric field. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000277100400004 |
Publication Date |
2009-11-17 |
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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 |
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ISSN |
1742-6596; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
|
Times cited |
2 |
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
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Call Number |
UA @ lucian @ c:irua:82861 |
Serial |
3667 |
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Permanent link to this record |
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Author |
Zhang, Y.; Fischetti, M.V.; Sorée, B.; Magnus, W.; Heyns, M.; Meuris, M. |
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Title |
Physical modeling of strain-dependent hole mobility in Ge p-channel inversion layers |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
106 |
Issue |
8 |
Pages |
083704,1-083704,9 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We present comprehensive calculations of the low-field hole mobility in Ge p-channel inversion layers with SiO2 insulator using a six-band k·p band-structure model. The cases of relaxed, biaxially, and uniaxially (both tensily and compressively) strained Ge are studied employing an efficient self-consistent methodmaking use of a nonuniform spatial mesh and of the Broyden second methodto solve the coupled envelope-wave function k·p and Poisson equations. The hole mobility is computed using the KuboGreenwood formalism accounting for nonpolar hole-phonon scattering and scattering with interfacial roughness. Different approximations to handle dielectric screening are also investigated. As our main result, we find a large enhancement (up to a factor of 10 with respect to Si) of the mobility in the case of uniaxial compressive stress similarly to the well-known case of Si. Comparison with experimental data shows overall qualitative agreement but with significant deviations due mainly to the unknown morphology of the rough Ge-insulator interface, to additional scattering with surface optical phonon from the high- insulator, to Coulomb scattering interface traps or oxide chargesignored in our calculationsand to different channel structures employed. |
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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 |
000271358100050 |
Publication Date |
2009-10-20 |
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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 |
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ISSN |
0021-8979; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.068 |
Times cited |
29 |
Open Access |
|
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Notes |
|
Approved |
Most recent IF: 2.068; 2009 IF: 2.072 |
|
|
Call Number |
UA @ lucian @ c:irua:80137 |
Serial |
2617 |
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Permanent link to this record |
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Author |
Magnus, W.; Brosens, F.; Sorée, B. |
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Title |
Modeling drive currents and leakage currents : a dynamic approach |
Type |
A1 Journal article |
|
Year |
2009 |
Publication |
Journal of computational electronics |
Abbreviated Journal |
J Comput Electron |
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Volume |
8 |
Issue |
3/4 |
Pages |
307-323 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
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Abstract |
The dynamics of electrons and holes propagating through the nano-scaled channels of modern semiconductor devices can be seen as a widespread manifestation of non-equilibrium statistical physics and its ruling principles. In this respect both the devices that are pushing conventional CMOS technology towards the final frontiers of Moores law and the upcoming set of alternative, novel nanostructures grounded on entirely new concepts and working principles, provide an almost unlimited playground for assessing physical models and numerical techniques emerging from classical and quantum mechanical non-equilibrium theory. In this paper we revisit the Boltzmann as well as the WignerBoltzmann equation which offers a valuable platform to study transport of charge carriers taking part in drive currents. We focus on a numerical procedure that regained attention recently as an alternative tool to solve the time-dependent Boltzmann equation for inhomogeneous systems, such as the channel regions of field-effect transistors, and we discuss its extension to the WignerBoltzmann equation. Furthermore, we pay attention to the calculation of tunneling leakage currents. The latter typically occurs in nano-scaled transistors when part of the carrier distribution sustaining the drive current is found to tunnel into the gate due the presence of an ultra-thin insulating barrier separating the gate from the channel region. In particular, we discuss the paradox related to the very existence of leakage currents established by electrons occupying quasi-bound states, while the (real) wave functions of the latter cannot carry net currents. Finally, we describe a simple model to resolve the paradox as well as to estimate gate currents provided the local carrier generation rates largely exceed the tunneling rates. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
S.l. |
Editor |
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Language |
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Wos |
000208236100009 |
Publication Date |
2009-09-28 |
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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 |
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ISSN |
1569-8025;1572-8137; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.526 |
Times cited |
4 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.526; 2009 IF: NA |
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Call Number |
UA @ lucian @ c:irua:89503 |
Serial |
2110 |
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Permanent link to this record |
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Author |
Pourghaderi, M.A.; Magnus, W.; Sorée, B.; Meuris, M.; de Meyer, K.; Heyns, M. |
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Title |
Ballistic current in metal-oxide-semiconductor field-effect transistors: the role of device topology |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
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Volume |
106 |
Issue |
5 |
Pages |
053702,1-053702,8 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
In this study we investigate the effect of device topology on the ballistic current in n-channel metal-oxide-semiconductor field-effect transistors. Comparison of the nanoscale planar and double-gate devices reveals that, down to a certain thickness of the double gate film, the ballistic current flowing in the double gate device is twice as large compared to its planar counterpart. On the other hand, further thinning of the film beyond this threshold is found to change noticeably the confinement and transport characteristics, which are strongly depending on the film material and the surface orientation. For double gate Ge and Si devices there exists a critical film thickness below which the transverse gate field is no longer effectively screened by the inversion layer electron gas and mutual inversion of the two gates is turned on. In the case of GaAs and other similar IIIV compounds, a decrease in the film thickness may drastically change the occupation of the L-valleys and therefore amend the transport properties. The simulation results show that, in both cases, the ballistic current and the transconductance are considerably enhanced. |
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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 |
000269850300052 |
Publication Date |
2009-09-03 |
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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 |
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ISSN |
0021-8979; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.068 |
Times cited |
3 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.068; 2009 IF: 2.072 |
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Call Number |
UA @ lucian @ c:irua:79744 |
Serial |
214 |
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Permanent link to this record |
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Author |
Pourghaderi, M.A.; Magnus, W.; Sorée, B.; Meuris, M.; de Meyer, K.; Heyns, M. |
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Title |
Tunneling-lifetime model for metal-oxide-semiconductor structures |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
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Volume |
80 |
Issue |
8 |
Pages |
085315,1-085315,10 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
In this paper we investigate the basic physics of charge carriers (electrons) leaking out of the inversion layer of a metal-oxide-semiconductor capacitor with a biased gate. In particular, we treat the gate leakage current as resulting from two combined processes: (1) the time-dependent decay of electron wave packets representing the inversion-layer charge and (2) the local generation of new electrons replacing those that have leaked away. As a result, the gate current simply emerges as the ratio of the total charge in the inversion layer to the tunneling lifetime. The latter is extracted from the quantum dynamics of the decaying wave packets, while the generation rate is incorporated as a phenomenological source term in the continuity equation. Not only do the gate currents calculated with this model agree very well with experiment, the model also provides an onset to solve the paradox of the current-free bound states representing the resonances of the Schrödinger equation that governs the fully coupled metal-oxide-semiconductor system. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000269639300076 |
Publication Date |
2009-08-21 |
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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 |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
2 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
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Call Number |
UA @ lucian @ c:irua:78294 |
Serial |
3763 |
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Permanent link to this record |
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Author |
Brosens, F.; Magnus, W. |
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Title |
Carrier transport in nanodevices: revisiting the Boltzmann and Wigner distribution functions |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
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Volume |
246 |
Issue |
7 |
Pages |
1656-1661 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
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Abstract |
In principle, transport of charged carriers in nanometer sized solid-state devices can be fully characterized once the non-equilibrium distribution function describing the carrier ensemble is known. In this light, we have revisited the Boltzmann and the Wigner distribution functions and the framework in which they emerge from the classical respectively quantum mechanical Liouville equation. We have assessed the method of the characteristic curves as a potential workhorse to solve the time dependent Boltzmann equation for carriers propagating through spatially non-uniform systems, such as nanodevices. In order to validate the proposed solution strategy, we numerically solve the Boltzmann equation for a one-dimensional conductor mimicking the basic features of a biased low-dimensional transistor operating in the on-state. Finally, we propose a computational scheme capable of extending the benefits of the above mentioned solution strategy when it comes to solve the Wigner-Liouville equation. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Berlin |
Editor |
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Language |
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Wos |
000268659100033 |
Publication Date |
2009-04-22 |
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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 |
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ISSN |
0370-1972;1521-3951; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.674 |
Times cited |
8 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.674; 2009 IF: 1.150 |
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Call Number |
UA @ lucian @ c:irua:77953 |
Serial |
284 |
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Permanent link to this record |
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Author |
Li, B.; Partoens, B.; Peeters, F.M.; Magnus, W. |
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Title |
Dielectric mismatch effect on coupled shallow impurity states in a semiconductor nanowire |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Physical review : B : solid state |
Abbreviated Journal |
Phys Rev B |
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Volume |
79 |
Issue |
8 |
Pages |
085306,1-085306,7 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Coupled shallow impurity states in a freestanding semiconductor nanowire and in a semiconductor nanowire surrounded by a metallic gate are studied within the effective-mass approximation. Bonding and antibonding states are found due to the coupling of the two impurities, and their energy converges with increasing distance di between the two impurities. The dependences of the binding energy on the wire radius R, the distance di between the two impurities, and the impurity radial position in the nanowire are examined. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
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Language |
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Wos |
000263816000051 |
Publication Date |
2009-02-09 |
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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 |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
11 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.836; 2009 IF: 3.475 |
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Call Number |
UA @ lucian @ c:irua:76223 |
Serial |
691 |
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Permanent link to this record |
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Author |
Slachmuylders, A.F.; Partoens, B.; Magnus, W.; Peeters, F.M. |
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Title |
Neutral shallow donors near a metallic interface |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Microelectronics journal |
Abbreviated Journal |
Microelectron J |
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Volume |
40 |
Issue |
4/5 |
Pages |
753-755 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The effect of a metallic gate on the bound states of a shallow donor located near the gate is studied. We calculate the energy spectrum as a function of the distance between the metallic gate and the donor and find an anti-crossing behavior in the energy levels for certain distances. We show how a transverse electric field can tune the average position of the electron with respect to the metallic gate and the impurity. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Luton |
Editor |
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Language |
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Wos |
000265870200024 |
Publication Date |
2009-02-04 |
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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 |
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ISSN |
0026-2692; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.163 |
Times cited |
1 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.163; 2009 IF: 0.778 |
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Call Number |
UA @ lucian @ c:irua:77029 |
Serial |
2296 |
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Permanent link to this record |
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Author |
Kerner, C.; Hackens, B.; Golubović, D.S.; Poli, S.; Faniel, S.; Magnus, W.; Schoenmaker, W.; Bayot, V.; Maes, H. |
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Title |
Control and readout of current-induced magnetic flux quantization in a superconducting transformer |
Type |
A1 Journal article |
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Year |
2009 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
Supercond Sci Tech |
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Volume |
22 |
Issue |
2 |
Pages |
025001,1-025001,4 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We demonstrate a simple and robust method for inducing and detecting changes of magnetic flux quantization in the absence of an externally applied magnetic field. In our device, an isolated ring is interconnected with two access loops via permalloy cores, forming a superconducting transformer. By applying and tuning a direct current at the first access loop, the number of flux quanta trapped in the isolated ring is modified without the aid of an external field. The flux state of the isolated ring is simply detected by recording the evolution of the critical current of the second access loop. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000262786000003 |
Publication Date |
2008-12-24 |
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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 |
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ISSN |
0953-2048;1361-6668; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.878 |
Times cited |
2 |
Open Access |
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Notes |
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Approved |
Most recent IF: 2.878; 2009 IF: 2.694 |
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Call Number |
UA @ lucian @ c:irua:76001 |
Serial |
497 |
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Permanent link to this record |