Records |
Author |
Chaves, A.; Farias, G.A.; Peeters, F.M.; Ferreira, R. |
Title |
The Split-operator technique for the study of spinorial wavepacket dynamics |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Communications in computational physics |
Abbreviated Journal |
Commun Comput Phys |
Volume |
17 |
Issue |
17 |
Pages |
850-866 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The split-operator technique for wave packet propagation in quantum systems is expanded here to the case of propagatingwave functions describing Schrodinger particles, namely, charge carriers in semiconductor nanostructures within the effective mass approximation, in the presence of Zeeman effect, as well as of Rashba and Dresselhaus spin-orbit interactions. We also demonstrate that simple modifications to the expanded technique allow us to calculate the time evolution of wave packets describing Dirac particles, which are relevant for the study of transport properties in graphene. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000353695400010 |
Publication Date |
2015-03-24 |
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 |
1815-2406;1991-7120; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.004 |
Times cited |
24 |
Open Access |
|
Notes |
; The authors gratefully acknowledge fruitful discussions with J. M. Pereira Jr. and R. N. Costa Filho. This work was financially supported by CNPq through the INCT-NanoBioSimes and the Science Without Borders programs (contract 402955/ 2012-9), PRONEX/FUNCAP, CAPES, the Bilateral programme between Flanders and Brazil, and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 2.004; 2015 IF: 1.943 |
Call Number |
c:irua:126028 |
Serial |
3593 |
Permanent link to this record |
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Author |
Cagno, S.; Cosyns, P.; Ceglia, A.; Nys, K.; Janssens, K. |
Title |
The use of vitrum obsianum in the Roman Empire: some new insights and future prospects |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Periodico di mineralogia |
Abbreviated Journal |
Period Mineral |
Volume |
84 |
Issue |
3a |
Pages |
465-482 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
The research on the use of obsidian in the Mediterranean is extensive but concerns almost exclusively volcanic glass from prehistoric and Bronze Age contexts. The consumption of obsidian during the Roman imperial period, however, has only occasionally received attention. Never a comprehensive account on what the Romans made in vitrum obsianum has been set up, nor have the sources exploited by them been examined. This paper provides a concise overview of the current knowledge on obsidian during the Roman imperial period and offers an introductory outline on potential research. The ancient writers inform us about the use of volcanic glass to create exclusive vessels, gemstones, mirrors and sculpture, but also about the creation of black appearing man-made glass initiated as a cheap and easier workable substitute of obsidian. The archaeological data on the other hand propose a more complex story with the occurrence of obsidian chunks in early Roman secondary glass workshops, and the bulky use of obsidian in late Antiquity to produce tesserae for the creation of wall and vault mosaics. Because it is extremely difficult to visually distinguish natural obsidian from man-made glass imitations we present in this paper data collected by means of non-destructive chemico-physical analyses SEM-EDX, portable X-ray fluorescence (p-XRF) and Raman spectroscopy to easily distinguish man-made glass from natural obsidian. In particular the use of portable instruments makes possible in situ analysis of objects in archaeological depots or museum collections to help defining distribution networks to better understand the shifting consumption patterns in Antiquity. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000365632500007 |
Publication Date |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0369-8963 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
0.883 |
Times cited |
2 |
Open Access |
|
Notes |
; Our sincere gratitude goes to Cecile Evers and Natacha Masar to have granted permission for studying and analysing various obsidian artefacts within the collections of the Royal Museums of Art and History, Brussels (Belgium). We are also very grateful to Roald Doctor, Daniele Foy and Laudine Robin, respectively for having provided the material from Carthage, for the Sidi Jdidi tessera and Lyon. Our appreciation also goes to Ian Freestone and Andrew Meek respectively for having worked out and provided the internal report on the horse foreleg in the British Museum. Finally we wish to thank Jennifer Price, Maria Grazia Diani respectively for the information on the Stanwick fragment and the piece in the Pogliaghi-Varesse collection. This research was supported by the Hercules Foundation (Brussels) with the grant AUHA09004 and FWO (Brussels, Belgium) projects no. G.0C12.13 and G.01769.09 and partly by the Research Council of Norway through its Centres of Excellence funding scheme, project number 223268/ F50. ; |
Approved |
Most recent IF: 0.883; 2015 IF: 0.464 |
Call Number |
UA @ admin @ c:irua:130244 |
Serial |
5876 |
Permanent link to this record |
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Author |
Saha, S.; Badhe, N.; Seuntjens, D.; Vlaeminck, S.E.; Biswas, R.; Nandy, T. |
Title |
Effective carbon and nutrient treatment solutions for mixed domestic-industrial wastewater in India |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Water science and technology |
Abbreviated Journal |
|
Volume |
72 |
Issue |
4 |
Pages |
651-657 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
The present study evaluates effectiveness of up-flow anaerobic sludge blanket (UASB) reactor followed by two post-anaerobic treatment options, namely free-surface, up-flow constructed wetland (FUP-CW) and oxygen-limited anaerobic nitrification/denitrification (OLAND) processes in treating sewage from the peri-urban areas in India receiving illegal industrial infiltrations. The UASB studies yielded robust results towards fluctuating strength of sewage and consistently removed 87-98% chemical oxygen demand (COD) at a hydraulic retention time of 1.5-2 d. The FUP-CW removed 68.5 +/- 13% COD, 68 +/- 3% NH4+-N, 38 +/- 5% PO43--P, 97.6 +/- 5% suspended particles and 97 +/- 13% fecal coliforms. Nutrient removal was found to be limiting in FUP-CW, especially in winter. Nitrogen removal in the OLAND process were 100 times higher than the FUP-CW process. Results show that UASB followed by FUP-CW can be an excellent, decentralized sewage treatment option, except during winter when nutrient removal is limited in FUP-CW. Hence, the study proposes bio-augmentation of FUP-CW with OLAND biomass for overall improvement in the performance of UASB followed by FUP-CW process. |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000359387200019 |
Publication Date |
2015-08-06 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0273-1223; 1996-9732 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:127775 |
Serial |
7840 |
Permanent link to this record |
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Author |
Dubois, M.; Hoogmartens, R.; Van Passel, S.; Van Acker, K.; Vanderreydt, I. |
Title |
Innovative market-based policy instruments for waste management : a case study on shredder residues in Belgium |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Waste Management & Research |
Abbreviated Journal |
Waste Manage Res |
Volume |
33 |
Issue |
10 |
Pages |
886-893 |
Keywords |
A1 Journal article; Economics; Engineering Management (ENM) |
Abstract |
In an increasingly complex waste market, market-based policy instruments, such as disposal taxes, can give incentives for sustainable progress while leaving flexibility for innovation. However, implementation of disposal taxes is often criticised by domestic waste handlers that fear to be outcompeted by competitors in other countries. The article discusses three innovative market-based instruments that limit the impact on international competitiveness: Tradable recycling credits, refunded disposal taxes and differentiated disposal taxes. All three instruments have already been implemented for distinct environmental policies in Europe. In order to illustrate how these instruments can be used for waste policy, the literature review is complemented with a case study on shredder residues from metal-containing waste streams in Belgium. The analysis shows that a conventional disposal tax remains the most efficient, simple and transparent instrument. However, if international competition is a significant issue or if political support is weak, refunded and differentiated disposal taxes can have an added value as second-best instruments. Tradable recycling credits are not an appropriate instrument for use in small waste markets with market power. In addition, refunded taxes create similar incentives, but induce lower transactions costs. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000361818000004 |
Publication Date |
2015-09-22 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0734-242x; 1096-3669 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
1.803 |
Times cited |
1 |
Open Access |
|
Notes |
; The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The research has been funded by the Flemish Government through the policy research centres programme. ; |
Approved |
Most recent IF: 1.803; 2015 IF: 1.297 |
Call Number |
UA @ admin @ c:irua:129876 |
Serial |
6217 |
Permanent link to this record |
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Author |
Rather, J.A.; Pilehvar, S.; De Wael, K. |
Title |
Polycyclodextrin and carbon nanotubes as composite for tyrosinase immobilization and its superior electrocatalytic activity towards butylparaben an endocrine disruptor |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of nanoscience and nanotechnology |
Abbreviated Journal |
|
Volume |
15 |
Issue |
5 |
Pages |
3365-3372 |
Keywords |
A1 Journal article; Engineering sciences. Technology; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
We developed a protocol for the immobilization of tyrosinase (Tyr) on the composite of polycyclodextrin polymer (CDP) and carbon nanotubes for the detection of an endocrine disruptor, i.e., butylparaben (BP). The formation of the CDP polymer was characterized by UV-Vis spectrophotometry. The conducting film of cross-linked CDP and carbon nanotubes, displays excellent matrix capabilities for Tyr immobilization. The host-guest chemical reaction ability of CD and the ππ stacking interaction assure the bioactivity of Tyr towards butylparaben. The developed biosensor was characterized electrochemically by electrochemical impedance spectroscopy. The enzyme-substrate kinetic parameters such as the apparent Michaelis-Menten constant (K M app) was measured under saturated substrate concentration. The determination of butylparaben was carried out by using square wave voltammetry over the concentration range of 2.1 to 35.4 μM with a detection limit of 0.1 μM. The fabricated biosensor was successfully applied in real-life cosmetic samples with good recovery ranging from 98.5 to 102.8%. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000347435200007 |
Publication Date |
2014-10-01 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1533-4899 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
3 |
Open Access |
|
Notes |
; The authors are highly thankful for the mobility grant (Non-Europe Postdoc Fellowship) for one of the author (Jahangir Ahmad Rather) supported by the Belgian Federal Science Policy (Belspo) co-funded by the Marie Curie Actions from the European Commission. Sanaz Pilehvar is funded by BOF-DOCPRO UA. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:119550 |
Serial |
5776 |
Permanent link to this record |
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Author |
McCalla, E.; Prakash, A.S.; Berg, E.; Saubanere, M.; Abakumov, A.M.; Foix, D.; Klobes, B.; Sougrati, M.T.; Rousse, G.; Lepoivre, F.; Mariyappan, S.; Doublet, M.L.; Gonbeau, D.; Novak, P.; Van Tendeloo, G.; Hermann, R.P.; Tarascon, J.M.; |
Title |
Reversible Li-intercalation through oxygen reactivity in Li-rich Li-Fe-Te oxide materials |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of the electrochemical society |
Abbreviated Journal |
J Electrochem Soc |
Volume |
162 |
Issue |
162 |
Pages |
A1341-A1351 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Lithium-rich oxides are a promising class of positive electrode materials for next generation lithium-ion batteries, and oxygen plays a prominent role during electrochemical cycling either by forming peroxo-like species and/or by irreversibly forming oxygen gas during first charge. Here, we present Li-Fe-Te-O materials which show a tremendous amount of oxygen gas release. This oxygen release accounts for nearly all the capacity during the first charge and results in vacancies as seen by transmission electron microscopy. There is no oxidation of either metal during charge but significant changes in their environments. These changes are particularly extreme for tellurium. XRD and neutron powder diffraction both show limited Changes during cycling and no appreciable change in lattice parameters. A density functional theory study of this material is performed and demonstrates that the holes created on some of the oxygen atoms upon oxidation are partially stabilized through the formation of shorter O-O bonds, i.e. (O-2)(n-) species which on further delithiation show a spontaneous O-2 de-coordination from the cationic network and migration to the now empty lithium layer. The rate limiting step during charge is undoubtedly the diffusion of oxygen either out along the lithium layer or via columns of oxygen atoms. (C) 2015 The Electrochemical Society. All rights reserved. |
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 |
000355643700030 |
Publication Date |
2015-04-29 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0013-4651;1945-7111; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.259 |
Times cited |
23 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.259; 2015 IF: 3.266 |
Call Number |
c:irua:126445 |
Serial |
2903 |
Permanent link to this record |
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Author |
Vasylenko, A.A.; Misko, V.R. |
Title |
Nonlinear transport of the Wigner crystal in symmetric and asymmetric FET-like structures : nonlinear transport of the Wigner crystal on superfluid He-4 in quasi-one-dimensional channels with symmetric and asymmetric constrictions |
Type |
A1 Journal article |
Year |
2015 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
Volume |
88 |
Issue |
88 |
Pages |
105 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
When floating on a two-dimensional surface of superfluid He-4, electrons arrange themselves in two-dimensional crystalline structure known as Wigner crystal. In channels, the boundaries interfere the crystalline order and in case of very narrow channels one observes a quasi-one-dimensional (quasi-1D) Wigner crystal formed by just a few rows of electrons and, ultimately, one row in the “quantum wire” regime. Recently, the “quantum wire” regime was accessed experimentally [D.G. Rees, H. Totsuji, K. Kono, Phys. Rev. Lett. 108, 176801 (2012)] resulting in unusual transport phenomena such as, e.g., oscillations in the electron conductance. Using molecular dynamics simulations, we study the nonlinear transport of electrons in channels with various types of constrictions: single and multiple symmetric and asymmetric geometrical constrictions with varying width and length, and saddle-point-type potentials with varying gate voltage. In particular, we analyze the average particle velocity of the particles and the corresponding electron current versus the driving force or the gate voltage. We have revealed a significant difference in the dynamics for long and short constrictions: The oscillations of the average velocity of the particles for the systems with short constrictions exhibit a clear correlation with the transitions between the states with different numbers of rows of particles; on the other hand, for the systems with longer constrictions these oscillations are suppressed. The obtained results qualitatively agree with the experimental observations. Next, we propose a FET-like structure that consists of a channel with asymmetric constrictions. We show that applying a transverse bias results either in increase of the average particle velocity or in its suppression thus allowing a flexible control tool over the electron transport. The advantage of the asymmetric FET is that it does not have a gate and it allows an easy control of relatively large electron flow. Furthermore, the asymmetric device can be used for rectification of an ac-driven electron flow. Our results bring important insights into the dynamics of electrons floating on the surface of superfluid He-4 in channels with constrictions and allow the effective control over the electron transport. |
Address |
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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 |
000353065100002 |
Publication Date |
2015-04-16 |
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 |
1434-6028;1434-6036; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.461 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.461; 2015 IF: 1.345 |
Call Number |
c:irua:125997 |
Serial |
2359 |
Permanent link to this record |
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Author |
Hai, G.-Q.; Peeters, F.M. |
Title |
Hamiltonian of a many-electron system with single-electron and electron-pair states in a two-dimensional periodic potential |
Type |
A1 Journal article |
Year |
2015 |
Publication |
European physical journal : B : condensed matter and complex systems |
Abbreviated Journal |
Eur Phys J B |
Volume |
88 |
Issue |
88 |
Pages |
20 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Based on the metastable electron-pair energy band in a two-dimensional (2D) periodic potential obtained previously by Hai and Castelano [J. Phys.: Condens. Matter 26, 115502 (2014)], we present in this work a Hamiltonian of many electrons consisting of single electrons and electron pairs in the 2D system. The electron-pair states are metastable of energies higher than those of the single-electron states at low electron density. We assume two different scenarios for the single-electron band. When it is considered as the lowest conduction band of a crystal, we compare the obtained Hamiltonian with the phenomenological model Hamiltonian of a boson-fermion mixture proposed by Friedberg and Lee [Phys. Rev. B 40, 6745 (1989)]. Single-electron-electron-pair and electron-pair-electron-pair interaction terms appear in our Hamiltonian and the interaction potentials can be determined from the electron-electron Coulomb interactions. When we consider the single-electron band as the highest valence band of a crystal, we show that holes in this valence band are important for stabilization of the electron-pair states in the system. |
Address |
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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 |
000347776800005 |
Publication Date |
2015-01-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
1434-6028;1434-6036; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.461 |
Times cited |
2 |
Open Access |
|
Notes |
; This work was supported by FAPESP and CNPq (Brazil). ; |
Approved |
Most recent IF: 1.461; 2015 IF: 1.345 |
Call Number |
c:irua:125317 |
Serial |
1406 |
Permanent link to this record |
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Author |
Shestakov, M.V.; Meledina, M.; Turner, S.; Baekelant, W.; Verellen, N.; Chen, X.; Hofkens, J.; Van Tendeloo, G.; Moshchalkov, V.V. |
Title |
Luminescence of fixed site Ag nanoclusters in a simple oxyfluoride glass host and plasmon absorption of amorphous Ag nanoparticles in a complex oxyfluoride glass host |
Type |
P1 Proceeding |
Year |
2015 |
Publication |
Proceedings of the Society of Photo-optical Instrumentation Engineers
T2 – 8th International Conference on Photonics, Devices, and System VI, AUG 27-29, 2014, Prague, CZECH REPUBLIC |
Abbreviated Journal |
|
Volume |
|
Issue |
|
Pages |
Unsp 94501n |
Keywords |
P1 Proceeding; Electron microscopy for materials research (EMAT) |
Abstract |
Ag nanocluster-doped glasses have been prepared by a conventional melt-quenching method. The effect of melt temperature and dwell time on the formation of Ag nanoclusters and Ag nanoparticles in simple host oxyfluoride glasses has been studied. The increase of melt temperature and dwell time results in the dissolution of Ag nanoparticles and substantial red-shift of absorption and photoluminescence spectra of the prepared glasses. The quantum yield of the glasses is similar to 5% and does not depend on melt temperature and dwell time. The prepared glasses may be used as red phosphors or down-conversion layers for solar-cells. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
Spie-int soc optical engineering |
Place of Publication |
Bellingham |
Editor |
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Language |
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Wos |
000349404500057 |
Publication Date |
2015-01-06 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
9450 |
Series Issue |
|
Edition |
|
ISSN |
978-1-62841-566-7 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
|
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:144783 |
Serial |
4668 |
Permanent link to this record |
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Author |
Liu, Y.-X.; Zhang, Y.-R.; Bogaerts, A.; Wang, Y.-N. |
Title |
Electromagnetic effects in high-frequency large-area capacitive discharges : a review |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of vacuum science and technology: A: vacuum surfaces and films |
Abbreviated Journal |
J Vac Sci Technol A |
Volume |
33 |
Issue |
33 |
Pages |
020801 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
In traditional capacitively coupled plasmas, the discharge can be described by an electrostatic model, in which the Poisson equation is employed to determine the electrostatic electric field. However, current plasma reactors are much larger and driven at a much higher frequency. If the excitation wavelength k in the plasma becomes comparable to the electrode radius, and the plasma skin depth d becomes comparable to the electrode spacing, the electromagnetic (EM) effects will become significant and compromise the plasma uniformity. In this regime, capacitive discharges have to be described by an EM model, i.e., the full set of Maxwells equations should be solved to address the EM effects. This paper gives an overview of the theory, simulation and experiments that have recently been carried out to understand these effects, which cause major uniformity problems in plasma processing for microelectronics and flat panel display industries. Furthermore, some methods for improving the plasma uniformity are also described and compared. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
A v s amer inst physics |
Place of Publication |
Melville |
Editor |
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Language |
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Wos |
000355739500007 |
Publication Date |
2015-02-12 |
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 |
0734-2101;1520-8559; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.374 |
Times cited |
10 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.374; 2015 IF: 2.322 |
Call Number |
c:irua:123541 |
Serial |
903 |
Permanent link to this record |
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Author |
Zanin, L.; Tomasi, N.; Rizzardo, C.; Gottardi, S.; Terzano, R.; Alfeld, M.; Janssens, K.; De Nobili, M.; Mimmo, T.; Cesco, S. |
Title |
Iron allocation in leaves of Fe-deficient cucumber plants fed with natural Fe complexes |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physiologia plantarum |
Abbreviated Journal |
Physiol Plantarum |
Volume |
154 |
Issue |
1 |
Pages |
82-94 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Iron (Fe) sources available for plants in the rhizospheric solution are mainly a mixture of complexes between Fe and organic ligands, including phytosiderophores (PS) and water-extractable humic substances (WEHS). In comparison with the other Fe sources, Fe-WEHS are more efficiently used by plants, and experimental evidences show that Fe translocation contributes to this better response. On the other hand, very little is known on the mechanisms involved in Fe allocation in leaves. In this work, physiological and molecular processes involved in Fe distribution in leaves of Fe-deficient Cucumis sativus supplied with Fe-PS or Fe-WEHS up to 5days were studied combining different techniques, such as radiochemical experiments, synchrotron micro X-ray fluorescence, real-time reverse transcription polymerase chain reaction and in situ hybridization. In Fe-WEHS-fed plants, Fe was rapidly (1day) allocated into the leaf veins, and after 5days, Fe was completely transferred into interveinal cells; moreover, the amount of accumulated Fe was much higher than with Fe-PS. This redistribution in Fe-WEHS plants was associated with an upregulation of genes encoding a ferric(III)-chelate reductase (FRO), a Fe2+ transporter (IRT1) and a natural resistance-associated macrophage protein (NRAMP). The localization of FRO and IRT1 transcripts next to the midveins, beside that of NRAMP in the interveinal area, may suggest a rapid and efficient response induced by the presence of Fe-WEHS in the extra-radical solution for the allocation in leaves of high amounts of Fe. In conclusion, Fe is more efficiently used when chelated to WEHS than PS and seems to involve Fe distribution and gene regulation of Fe acquisition mechanisms operating in leaves. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000353067500007 |
Publication Date |
2014-10-07 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0031-9317 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.33 |
Times cited |
14 |
Open Access |
|
Notes |
; Research was supported by grants from Italian MIUR (FIRB-Programma 'Futuro in Ricerca') and Free University of Bolzano (TN5056). Synchrotron experiments at HASYLAB were financially supported by the European Community-Research Infrastructure Action under the FP6 'Structuring the European Research Area' Program I (Integrating Activity on Synchrotron and Free Electron Laser Science; project: contract RII3-CT-2004-506008). We thank Karen Appel for her scientific and technical support in obtaining the experimental data at Beamline L (HASYLAB, DESY, Hamburg, Germany). ; |
Approved |
Most recent IF: 3.33; 2015 IF: 3.138 |
Call Number |
UA @ admin @ c:irua:132500 |
Serial |
5678 |
Permanent link to this record |
|
|
|
Author |
Pittarello, L.; Ji, G.; Yamaguchi, A.; Schryvers, D.; Debaille, V.; Claeys, P. |
Title |
From olivine to ringwoodite : a TEM study of a complex process |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Meteoritics and Planetary Science |
Abbreviated Journal |
Meteorit Planet Sci |
Volume |
50 |
Issue |
50 |
Pages |
944-957 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The study of shock metamorphism of olivine might help to constrain impact events in the history of meteorites. Although shock features in olivine are well known, so far, there are processes that are not yet completely understood. In shock veins, olivine clasts with a complex structure, with a ringwoodite rim and a dense network of lamellae of unidentified nature in the core, have been reported in the literature. A highly shocked (S5-6), L6 meteorite, Asuka 09584, which was recently collected in Antarctica by a Belgian-Japanese joint expedition, contains this type of shocked olivine clasts and has been, therefore, selected for detailed investigations of these features by transmission electron microscopy (TEM). Petrographic, geochemical, and crystallographic studies showed that the rim of these shocked clasts consists of an aggregate of nanocrystals of ringwoodite, with lower Mg/Fe ratio than the unshocked olivine. The clast's core consists of an aggregate of iso-oriented grains of olivine and wadsleyite, with higher Mg/Fe ratio than the unshocked olivine. This aggregate is crosscut by veinlets of nanocrystals of olivine, with extremely low Mg/Fe ratio. The formation of the ringwoodite rim is likely due to solid-state, diffusion-controlled, transformation from olivine under high-temperature conditions. The aggregate of iso-oriented olivine and wadsleyite crystals is interpreted to have formed also by a solid-state process, likely by coherent intracrystalline nucleation. Following the compression, shock release is believed to have caused opening of cracks and fractures in olivine and formation of olivine melt, which has lately crystallized under postshock equilibrium pressure conditions as olivine. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000354258400008 |
Publication Date |
2015-04-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1086-9379; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.391 |
Times cited |
8 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.391; 2015 IF: 3.104 |
Call Number |
c:irua:126058 |
Serial |
1283 |
Permanent link to this record |
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|
|
Author |
Van De Vijver, E.; Van Meirvenne, M.; Saey, T.; Delefortrie, S.; De Smedt, P.; De Pue, J.; Seuntjens, P. |
Title |
Combining multi-receiver electromagnetic induction and stepped frequency ground penetrating radar for industrial site investigation |
Type |
A1 Journal article |
Year |
2015 |
Publication |
European journal of soil science |
Abbreviated Journal |
|
Volume |
66 |
Issue |
4 |
Pages |
688-698 |
Keywords |
A1 Journal article; Sustainable Energy, Air and Water Technology (DuEL) |
Abstract |
The soil at industrial sites is frequently characterized by very heterogeneous properties, which are often related to physical disturbance and contamination. A conventional approach to characterize the soil, with only a limited number of invasive observations, fails to capture the full extent of soil heterogeneity. Proximal soil sensing provides efficient tools to record spatially dense soil information. Nevertheless, because the output of most sensors is affected by more than one soil property, the simultaneous characterization of different soil properties requires the use of multiple sensors. Here, we apply multi-receiver electromagnetic induction (EMI) and stepped frequency ground penetrating radar (GPR) to survey a former gasworks site in a seaport area of Belgium. We used the EMI and GPR sensors in a motorized system to obtain densely sampled measurements of apparent electrical conductivity, apparent magnetic susceptibility and contrasts in relative dielectric permittivity. Our study shows that the sensors give detailed information on the variation in these electromagnetic soil properties. Interpretation of the variation in terms of the stratification of the soil was hampered by localized anthropogenic disturbances. However, the sensors provided complementary information that enabled the identification, discrimination and accurate location of several of these localized disturbances, including underground utility services such as electric cables, buried structures such as the remains of foundations and contamination by salts. Because these represent typical targets in industrial site investigation, we conclude that multi-receiver EMI and stepped frequency GPR provide a useful set of tools to expedite the investigation of industrial sites. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000357341900008 |
Publication Date |
2015-02-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1351-0754 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:127112 |
Serial |
7684 |
Permanent link to this record |
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|
|
Author |
Clima, S.; Chen, Y.Y.; Fantini, A.; Goux, L.; Degraeve, R.; Govoreanu, B.; Pourtois, G.; Jurczak, M. |
Title |
Intrinsic tailing of resistive states distributions in amorphous <tex>HfOx </tex> and TaOx based resistive random access memories |
Type |
A1 Journal article |
Year |
2015 |
Publication |
IEEE electron device letters |
Abbreviated Journal |
Ieee Electr Device L |
Volume |
36 |
Issue |
36 |
Pages |
769-771 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We report on the ineffectiveness of programming oxide-based resistive random access memory (OxRAM) at low current with a program and verify algorithm due to intrinsic relaxation of the verified distribution to the natural state distribution obtained by single-pulse programming without verify process. Based on oxygen defect formation thermodynamics and on their diffusion barriers in amorphous HfOx and TaOx, we describe the intrinsic nature of tailing of the verified low resistive state and high resistive state distributions. We introduce different scenarios to explain fast distribution widening phenomenon, which is a fundamental limitation for OxRAM current scaling and device reliability. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000358570300011 |
Publication Date |
2015-06-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0741-3106 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.048 |
Times cited |
33 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.048; 2015 IF: 2.754 |
Call Number |
UA @ lucian @ c:irua:134412 |
Serial |
4200 |
Permanent link to this record |
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|
|
Author |
Petrovic, M.D.; Peeters, F.M. |
Title |
Fano resonances in the conductance of graphene nanoribbons with side gates |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
91 |
Issue |
91 |
Pages |
035444 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The control of side gates on the quantum electron transport in narrow graphene ribbons of different widths and edge types (armchair and zigzag) is investigated. The conductance exhibits Fano resonances with varying side gate potential. Resonant and antiresonant peaks in the conductance can be associated with the eigenstates of a closed system, and these peaks can be accurately fitted with a Fano line shape. The local density of states (LDOS) and the electron current show a specific behavior at these resonances, which depends on the ribbon edge type. In zigzag ribbons, transport is dominated by intervalley scattering, which is reflected in the transmission functions of individual modes. The side gates induce p-n interfaces near the edges at which the LDOS exhibits peaks. Near the resonance points, the electron current flows uniformly through the constriction, while near the antiresonances it creates vortices. In the armchair ribbons the LDOS spreads in areas of high potential, with current flowing near the edges. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000351217900005 |
Publication Date |
2015-01-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
17 |
Open Access |
|
Notes |
; This work was supported by the Methusalem programme of the Flemish government. ; |
Approved |
Most recent IF: 3.836; 2015 IF: 3.736 |
Call Number |
c:irua:125422 |
Serial |
1172 |
Permanent link to this record |
|
|
|
Author |
Venturi, F.; Calizzi, M.; Bals, S.; Perkisas, T.; Pasquini, L. |
Title |
Self-assembly of gas-phase synthesized magnesium nanoparticles on room temperature substrates |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Materials research express |
Abbreviated Journal |
Mater Res Express |
Volume |
2 |
Issue |
2 |
Pages |
015007 |
Keywords |
A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT) |
Abstract |
Magnesium nanoparticles (NPs) with initial size in the 10-50 nmrange were synthesized by inert gas condensation under helium flow and deposited on room temperature substrates. The morphology and crystal structure of the NPs ensemble were investigated as a function of the deposition time by complementary electron microscopy techniques, including high resolution imaging and chemical mapping. With increasing amount of material, strong coarsening phenomena were observed at room temperature: small NPs disappeared while large faceted NPs developed, leading to a 5-fold increase of the average NPs size within a few minutes. The extent of coarsening and the final morphology depended also on the nature of the substrate. Furthermore, large single-crystal NPs were seen to arise from the self-organization of primary NPs units, providing a mechanism for crystal growth. The dynamics of the self-assembly process involves the basic steps of NPs sticking, diffusion on substrate, coordinated rotation and attachment/coalescence. Key features are the surface energy anisotropy, reflected by the faceted shape of the NPs, and the low melting point of the material. The observed phenomena have strong implications in relation to the synthesis and stability of nanostructures based on Mg or other elements with similar features. |
Address |
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Corporate Author |
|
Thesis |
|
Publisher |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000369978500007 |
Publication Date |
2014-12-31 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2053-1591 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.068 |
Times cited |
14 |
Open Access |
Not_Open_Access |
Notes |
; Financial support by COST Action MP1103 'Nanostructured Materials for Solid-State Hydrogen Storage' is gratefully acknowledged. ; |
Approved |
Most recent IF: 1.068; 2015 IF: NA |
Call Number |
UA @ lucian @ c:irua:132275 |
Serial |
4240 |
Permanent link to this record |
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|
|
Author |
Becker, T.; Nelissen, K.; Cleuren, B. |
Title |
Current fluctuations in boundary driven diffusive systems in different dimensions : a numerical study |
Type |
A1 Journal article |
Year |
2015 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
17 |
Issue |
17 |
Pages |
055023 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We use kinetic Monte Carlo simulations to investigate current fluctuations in boundary driven generalized exclusion processes, in different dimensions. Simulation results are in full agreement with predictions based on the additivity principle and the macroscopic fluctuation theory. The current statistics are independent of the shape of the contacts with the reservoirs, provided they are macroscopic in size. In general, the current distribution depends on the spatial dimension. For the special cases of the symmetric simple exclusion process and the zero-range process, the current statistics are the same for all spatial dimensions. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000355282700001 |
Publication Date |
2015-05-27 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.786 |
Times cited |
5 |
Open Access |
|
Notes |
; We thank Christian Van den Broeck for bringing this problem to our attention. We are grateful to Bart Partoens and Carlo Vanderzande for a careful reading of the manuscript. This work was supported by the Flemish Science Foundation (Fonds Wetenschappelijk Onderzoek), Project No. G038811N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government-department EWI. ; |
Approved |
Most recent IF: 3.786; 2015 IF: 3.558 |
Call Number |
c:irua:126405 |
Serial |
592 |
Permanent link to this record |
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|
Author |
Woo, S.Y.; Gauquelin, N.; Nguyen, H.P.T.; Mi, Z.; Botton, G.A. |
Title |
Interplay of strain and indium incorporation in InGaN/GaN dot-in-a-wire nanostructures by scanning transmission electron microscopy |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
Volume |
26 |
Issue |
26 |
Pages |
344002 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The interplay between strain and composition is at the basis of heterostructure design to engineer new properties. The influence of the strain distribution on the incorporation of indium during the formation of multiple InGaN/GaN quantum dots (QDs) in nanowire (NW) heterostructures has been investigated, using the combined techniques of geometric phase analysis of atomic-resolution images and quantitative elemental mapping from core-loss electron energy-loss spectroscopy within scanning transmission electron microscopy. The variation in In-content between successive QDs within individual NWs shows a dependence on the magnitude of compressive strain along the growth direction within the underlying GaN barrier layer, which affects the incorporation of In-atoms to minimize the local effective strain energy. Observations suggest that the interfacial misfit between InGaN/GaN within the embedded QDs is mitigated by strain partitioning into both materials, and results in normal stresses inflicted by the presence of the surrounding GaN shell. These experimental measurements are linked to the local piezoelectric polarization fields for individual QDs, and are discussed in terms of the photoluminescence from an ensemble of NWs. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000359079500003 |
Publication Date |
2015-08-03 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.44 |
Times cited |
19 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.44; 2015 IF: 3.821 |
Call Number |
UA @ lucian @ c:irua:136278 |
Serial |
4504 |
Permanent link to this record |
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|
|
Author |
Scuracchio, P.; Dobry, A.; Costamagna, S.; Peeters, F.M. |
Title |
Tuning the polarized quantum phonon transmission in graphene nanoribbons |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
Volume |
26 |
Issue |
26 |
Pages |
305401 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
We propose systems that allow a tuning of the phonon transmission function T(omega) in graphene nanoribbons by using C-13 isotope barriers, antidot structures, and distinct boundary conditions. Phonon modes are obtained by an interatomic fifth-nearest neighbor force-constant model (5NNFCM) and T(omega) is calculated using the non-equilibrium Green's function formalism. We show that by imposing partial fixed boundary conditions it is possible to restrict contributions of the in-plane phonon modes to T(omega) at low energy. On the contrary, the transmission functions of out-of-plane phonon modes can be diminished by proper antidot or isotope arrangements. In particular, we show that a periodic array of them leads to sharp dips in the transmission function at certain frequencies omega(nu) which can be pre-defined as desired by controlling their relative distance and size. With this, we demonstrated that by adequate engineering it is possible to govern the magnitude of the ballistic transmission functions T(omega) in graphene nanoribbons. We discuss the implications of these results in the design of controlled thermal transport at the nanoscale as well as in the enhancement of thermo-electric features of graphene-based materials. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000358675900010 |
Publication Date |
2015-07-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.44 |
Times cited |
5 |
Open Access |
|
Notes |
; Discussions with C E Repetto, C R Stia and K H Michel are gratefully acknowledged. This work was partially supported by the Flemish Science Foundation (FWO-Vl) and PIP 11220090100392 of CONICET (Argentina). We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. ; |
Approved |
Most recent IF: 3.44; 2015 IF: 3.821 |
Call Number |
c:irua:127186 |
Serial |
3759 |
Permanent link to this record |
|
|
|
Author |
Chen, Y.; Hong-Yu, W.; Peeters, F.M.; Shanenko, A.A. |
Title |
Quantum-size effects and thermal response of anti-Kramer-Pesch vortex core |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
27 |
Issue |
27 |
Pages |
125701 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Since the 1960's it has been well known that the basic superconductive quantities can exhibit oscillations as functions of the thickness (diameter) in superconducting nanofilms (nanowires) due to the size quantization of the electronic spectrum. However, very little is known about the effects of quantum confinement on the microscopic properties of vortices. Based on a numerical solution to the Bogoliubov-de Gennes equations, we study the quantum-size oscillations of the vortex core resulting from the sequential interchange of the Kramer-Pesch and anti-Kramer-Pesch regimes with changing nanocylinder radius. The physics behind the anti-Kramer-Pesch anomaly is displayed by utilizing a semi-analytical Anderson approximate solution. We also demonstrate that the anti-Kramer-Pesch vortex core is robust against thermal smearing and results in a distinctive two-maxima structure in the local density of states, which can be used to identify the existence of the anti-Kramer-Pesch vortex. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000351294700018 |
Publication Date |
2015-03-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984;1361-648X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
4 |
Open Access |
|
Notes |
; This work was supported by the National Natural Science Foundation of China under Grant No. NSFC-11304134, the Flemish Science Foundation (FWO-Vl), and the Methusalem program. AAS acknowledges the support of the Brazilian agencies CNPq (grants 307552/2012-8 and 141911/2012-3) and FACEPE (APQ-0589-1.05/08). WHY acknowledges the support of Scientific Research Fund of Zhejiang Provincial Education Department (Y201120994). ; |
Approved |
Most recent IF: 2.649; 2015 IF: 2.346 |
Call Number |
c:irua:125460 |
Serial |
2787 |
Permanent link to this record |
|
|
|
Author |
de de Meux, A.J.; Pourtois, G.; Genoe, J.; Heremans, P. |
Title |
Comparison of the electronic structure of amorphous versus crystalline indium gallium zinc oxide semiconductor : structure, tail states and strain effects |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
Volume |
48 |
Issue |
48 |
Pages |
435104 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We study the evolution of the structural and electronic properties of crystalline indium gallium zinc oxide (IGZO) upon amorphization by first-principles calculation. The bottom of the conduction band (BCB) is found to be constituted of a pseudo-band of molecular orbitals that resonate at the same energy on different atomic sites. They display a bonding character between the s orbitals of the metal sites and an anti-bonding character arising from the interaction between the oxygen and metal s orbitals. The energy level of the BCB shifts upon breaking of the crystal symmetry during the amorphization process, which may be attributed to the reduction of the coordination of the cationic centers. The top of the valence band (TVB) is constructed from anti-bonding oxygen p orbitals. In the amorphous state, they have random orientation, in contrast to the crystalline state. This results in the appearance of localized tail states in the forbidden gap above the TVB. Zinc is found to play a predominant role in the generation of these tail states, while gallium hinders their formation. Last, we study the dependence of the fundamental gap and effective mass of IGZO on mechanical strain. The variation of the gap under strain arises from the enhancement of the anti-bonding interaction in the BCB due to the modification of the length of the oxygen-metal bonds and/or to a variation of the cation coordination. This effect is less pronounced for the amorphous material compared to the crystalline material, making amorphous IGZO a semiconductor of choice for flexible electronics. Finally, the effective mass is found to increase upon strain, in contrast to regular materials. This counterintuitive variation is due to the reduction of the electrostatic shielding of the cationic centers by oxygen, leading to an increase of the overlaps between the metal orbitals at the origin of the delocalization of the BCB. For the range of strain typically met in flexible electronics, the induced variation in the effective mass is found to be negligible (less than 1%). |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000365876300012 |
Publication Date |
2015-09-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0022-3727 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.588 |
Times cited |
23 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.588; 2015 IF: 2.721 |
Call Number |
UA @ lucian @ c:irua:130277 |
Serial |
4153 |
Permanent link to this record |
|
|
|
Author |
Mahmoudi, H.; Renn, O.; Hoffmann, V.; Van Passel, S.; Azadi, H. |
Title |
Social risk screening using a socio-political ambiguity approach : the case of organic agriculture in Iran |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal Of Risk Research |
Abbreviated Journal |
J Risk Res |
Volume |
18 |
Issue |
6 |
Pages |
747-770 |
Keywords |
A1 Journal article; Sociology; Engineering Management (ENM) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000356236300009 |
Publication Date |
2014-05-08 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1366-9877 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.34 |
Times cited |
1 |
Open Access |
|
Notes |
; H.M. thanks the Ministry of Science, Research, and Technology of Iran (MSRT) for a PhD fellowship. The authors wish to thank Dr. Stefan Burkart for his kind help to improve the English of the paper. ; |
Approved |
Most recent IF: 1.34; 2015 IF: 0.935 |
Call Number |
UA @ admin @ c:irua:127534 |
Serial |
6249 |
Permanent link to this record |
|
|
|
Author |
Shahraki, M.R.; Abedi-Sarvestani, A.; Seyedi, M.S.; Rafiaani Khachak, P.; Nieto-Garibay, A.; Van Passel, S.; Azadi, A. |
Title |
The perception by pastoralists of the factors influencing the appropriate distribution of livestock in the rangelands of north-east Iran |
Type |
A1 Journal article |
Year |
2015 |
Publication |
The Rangeland Journal |
Abbreviated Journal |
|
Volume |
37 |
Issue |
2 |
Pages |
191-197 |
Keywords |
A1 Journal article; Economics; Engineering Management (ENM) |
Abstract |
The distribution of livestock grazing is a key principle of range management. This study examines pastoralists perceptions of the factors that affect the distribution of livestock in the rangelands of the Neqab region of the Kashmar County in north-east Iran. Data were collected from the pastoralists on their perceptions of the managerial, biological and physical factors that influences the distribution of livestock, using both qualitative and quantitative assessments. Results showed that, the perception of the majority of pastoralists was that the distribution of livestock was average or good in the study area. It was perceived that the experience of herders and the size of the rangeland were the main factors influencing the distribution of livestock. Regression analyses showed that it was perceived that managerial factors had a more important role than biological and physical factors in the distribution of livestock and the proper use of the rangelands in north-east Iran. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000351863200007 |
Publication Date |
2015-02-18 |
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 |
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ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
; ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:129879 |
Serial |
6234 |
Permanent link to this record |
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Author |
de Sousa, A.A.; Chaves, A.; Pereira, T.A.S.; Farias, G.A.; Peeters, F.M. |
Title |
Quantum tunneling between bent semiconductor nanowires |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
118 |
Issue |
118 |
Pages |
174301 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We theoretically investigate the electronic transport properties of two closely spaced L-shaped semiconductor quantum wires, for different configurations of the output channel widths as well as the distance between the wires. Within the effective-mass approximation, we solve the time-dependent Schrodinger equation using the split-operator technique that allows us to calculate the transmission probability, the total probability current, the conductance, and the wave function scattering between the energy subbands. We determine the maximum distance between the quantum wires below which a relevant non-zero transmission is still found. The transmission probability and the conductance show a strong dependence on the width of the output channel for small distances between the wires. (C) 2015 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000364584200020 |
Publication Date |
2015-11-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
7 |
Open Access |
|
Notes |
; A. A. Sousa was financially supported by CAPES, under the PDSE Contract No. BEX 7177/13-5. T. A. S. Pereira was financially supported by PRONEX/CNPq/FAPEMAT 850109/2009 and by CAPES under process BEX 3299/13-9. This work was financially supported by PRONEX/CNPq/FUNCAP, the Science Without Borders program and the bilateral project CNPq-FWO. ; |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:129544 |
Serial |
4234 |
Permanent link to this record |
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Author |
Verreck, D.; Verhulst, A.S.; Van de Put, M.; Sorée, B.; Magnus, W.; Mocuta, A.; Collaert, N.; Thean, A.; Groeseneken, G. |
Title |
Full-zone spectral envelope function formalism for the optimization of line and point tunnel field-effect transistors |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
118 |
Issue |
118 |
Pages |
134502 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Efficient quantum mechanical simulation of tunnel field-effect transistors (TFETs) is indispensable to allow for an optimal configuration identification. We therefore present a full-zone 15-band quantum mechanical solver based on the envelope function formalism and employing a spectral method to reduce computational complexity and handle spurious solutions. We demonstrate the versatility of the solver by simulating a 40 nm wide In0.53Ga0.47As lineTFET and comparing it to p-n-i-n configurations with various pocket and body thicknesses. We find that the lineTFET performance is not degraded compared to semi-classical simulations. Furthermore, we show that a suitably optimized p-n-i-n TFET can obtain similar performance to the lineTFET. (C) 2015 AIP Publishing LLC. |
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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 |
000362668400025 |
Publication Date |
2015-10-01 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979; 1089-7550 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
9 |
Open Access |
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Notes |
; D. Verreck acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). This work was supported by imec's Industrial Affiliation Program. ; |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:128765 |
Serial |
4183 |
Permanent link to this record |
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Author |
Yagmurcukardes, M.; Sahin, H.; Kang, J.; Torun, E.; Peeters, F.M.; Senger, R.T. |
Title |
Pentagonal monolayer crystals of carbon, boron nitride, and silver azide |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
118 |
Issue |
118 |
Pages |
104303 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In this study, we present a theoretical investigation of structural, electronic, and mechanical properties of pentagonal monolayers of carbon (p-graphene), boron nitride (p-B2N4 and p-B4N2), and silver azide (p-AgN3) by performing state-of-the-art first principles calculations. Our total energy calculations suggest feasible formation of monolayer crystal structures composed entirely of pentagons. In addition, electronic band dispersion calculations indicate that while p-graphene and p-AgN3 are semiconductors with indirect bandgaps, p-BN structures display metallic behavior. We also investigate the mechanical properties (in-plane stiffness and the Poisson's ratio) of four different pentagonal structures under uniaxial strain. p-graphene is found to have the highest stiffness value and the corresponding Poisson's ratio is found to be negative. Similarly, p-B2N4 and p-B4N2 have negative Poisson's ratio values. On the other hand, the p-AgN3 has a large and positive Poisson's ratio. In dynamical stability tests based on calculated phonon spectra of these pentagonal monolayers, we find that only p-graphene and p-B2N4 are stable, but p-AgN3 and p-B4N2 are vulnerable against vibrational excitations. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000361636900028 |
Publication Date |
2015-09-08 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
79 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. was supported by a FWO Pegasus Long Marie Curie Fellowship. H.S. and R.T.S. acknowledge the support from TUBITAK through Project No. 114F397. ; |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
UA @ lucian @ c:irua:128415 |
Serial |
4223 |
Permanent link to this record |
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Author |
Berdiyorov, G.; Harrabi, K.; Mehmood, U.; Peeters, F.M.; Tabet, N.; Zhang, J.; Hussein, I.A.; McLachlan, M.A. |
Title |
Derivatization and diffusive motion of molecular fullerenes : ab initio and atomistic simulations |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
118 |
Issue |
118 |
Pages |
025101 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using first principles density functional theory in combination with the nonequilibrium Green's function formalism, we study the effect of derivatization on the electronic and transport properties of C-60 fullerene. As a typical example, we consider [6,6]-phenyl-C-61-butyric acid methyl ester (PCBM), which forms one of the most efficient organic photovoltaic materials in combination with electron donating polymers. Extra peaks are observed in the density of states (DOS) due to the formation of new electronic states localized at/near the attached molecule. Despite such peculiar behavior in the DOS of an isolated molecule, derivatization does not have a pronounced effect on the electronic transport properties of the fullerene molecular junctions. Both C-60 and PCBM show the same response to finite voltage biasing with new features in the transmission spectrum due to voltage induced delocalization of some electronic states. We also study the diffusive motion of molecular fullerenes in ethanol solvent and inside poly(3-hexylthiophene) lamella using reactive molecular dynamics simulations. We found that the mobility of the fullerene reduces considerably due to derivatization; the diffusion coefficient of C-60 is an order of magnitude larger than the one for PCBM. (c) 2015 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000357961000036 |
Publication Date |
2015-07-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979;1089-7550; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
2 |
Open Access |
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Notes |
; K.H., U.M. and I.A.H. would like to thank the National Science, Technology and Innovation Program of KACST for funding this research under Project No. 12-ENE2379-04. They also acknowledge support from KFUPM and Research Institute. ; |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
c:irua:127098 |
Serial |
652 |
Permanent link to this record |
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Author |
Zhao, C.X.; Xu, W.; Li, L.L.; Zhang, C.; Peeters, F.M. |
Title |
Terahertz plasmon-polariton modes in graphene driven by electric field inside a Fabry-Perot cavity |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
117 |
Issue |
117 |
Pages |
223104 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We present a theoretical study on plasmon-polariton modes in graphene placed inside an optical cavity and driven by a source-to-drain electric field. The electron velocity and electron temperature are determined by solving self-consistently the momentum-and energy-balance equations in which electron interactions with impurities, acoustic-, and optic-phonons are included. Based on many-body self-consistent field theory, we develop a tractable approach to study plasmon-polariton in an electron gas system. We find that when graphene is placed inside a Fabry-Perot cavity, two branches of the plasmon-polariton modes can be observed and these modes are very much optic-or plasmon-like. The frequencies of these modes depend markedly on driving electric field especially at higher resonant frequency regime. Moreover, the plasmon-polariton frequency in graphene is in terahertz (THz) bandwidth and can be tuned by changing the cavity length, gate voltage, and driving electric field. This work is pertinent to the application of graphene-based structures as tunable THz plasmonic devices. (C) 2015 AIP Publishing LLC. |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000356176100004 |
Publication Date |
2015-06-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979;1089-7550; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
13 |
Open Access |
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Notes |
; This work was supported by the Ministry of Science and Technology of China (Grant No. 2011YQ130018), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. F.M.P. was a specially appointed Professor for foreign expert at the Chinese Academy of Sciences. ; |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
c:irua:127076 |
Serial |
3507 |
Permanent link to this record |
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Author |
Torun, E.; Sahin, H.; Singh, S.K.; Peeters, F.M. |
Title |
Stable half-metallic monolayers of FeCl2 |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
106 |
Issue |
106 |
Pages |
192404 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The structural, electronic, and magnetic properties of single layers of Iron Dichloride (FeCl2) were calculated using first principles calculations. We found that the 1T phase of the single layer FeCl2 is 0.17 eV/unit cell more favorable than its 1H phase. The structural stability is confirmed by phonon calculations. We found that 1T-FeCl2 possess three Raman-active (130, 179, and 237 cm(-1)) and one infrared-active (279 cm(-1)) phonon branches. The electronic band dispersion of the 1T-FeCl2 is calculated using both gradient approximation of Perdew-Burke-Ernzerhof and DFT-HSE06 functionals. Both functionals reveal that the 1T-FeCl2 has a half-metallic ground state with a Curie temperature of 17 K. (C) 2015 AIP Publishing LLC. |
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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 |
000355008100020 |
Publication Date |
2015-05-13 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-6951;1077-3118; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
84 |
Open Access |
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Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. was supported by a FWO Pegasus Long Marie Curie Fellowship. ; |
Approved |
Most recent IF: 3.411; 2015 IF: 3.302 |
Call Number |
c:irua:126411 |
Serial |
3143 |
Permanent link to this record |
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Author |
Li, L.L.; Xu, W.; Peeters, F.M. |
Title |
Optical conductivity of topological insulator thin films |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
117 |
Issue |
117 |
Pages |
175305 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We present a detailed theoretical study on the optoelectronic properties of topological insulator thin film (TITFs). The k . p approach is employed to calculate the energy spectra and wave functions for both the bulk and surface states in the TITF. With these obtained results, the optical conductivities induced by different electronic transitions among the bulk and surface states are evaluated using the energy-balance equation derived from the Boltzmann equation. We find that for Bi2Se3-based TITFs, three characteristic regimes for the optical absorption can be observed. (i) In the low radiation frequency regime (photon energy (h) over bar omega < 200 meV), the free-carrier absorption takes place due to intraband electronic transitions. An optical absorption window can be observed. (ii) In the intermediate radiation frequency regime (200 < (h) over bar omega < 300 meV), the optical absorption is induced mainly by interband electronic transitions from surface states in the valance band to surface states in the conduction band and an universal value sigma(0) = e(2) / (8<(h)over bar>) for the optical conductivity can be obtained. (iii) In the high radiation frequency regime ((h) over bar omega > 300 meV), the optical absorption can be achieved via interband electronic transitions from bulk and surface states in the valance band to bulk and surface states in the conduction band. A strong absorption peak can be observed. These interesting findings indicate that optical measurements can be applied to identify the energy regimes of bulk and surface states in the TITF. (C) 2015 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000354984100615 |
Publication Date |
2015-05-06 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-8979;1089-7550; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
9 |
Open Access |
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Notes |
; This work was supported by the National Natural Science Foundation of China (Grant No. 11304316), Ministry of Science and Technology of China (Grant No. 2011YQ130018), Department of Science and Technology of Yunnan Province, and by the Chinese Academy of Sciences. ; |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
c:irua:126412 |
Serial |
2473 |
Permanent link to this record |