Records |
Author |
Abdullah, H.M.; Bahlouli, H.; Peeters, F.M.; Van Duppen, B. |
Title |
Confined states in graphene quantum blisters |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
30 |
Issue |
38 |
Pages |
385301 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Bilayer graphene samples may exhibit regions where the two layers are locally delaminated forming a so-called quanttun blister in the graphene sheet. Electron and hole states can be confined in this graphene quantum blisters (GQB) by applying a global electrostatic bias. We scrutinize the electronic properties of these confined states under the variation of interlayer bias, coupling, and blister's size. The spectra display strong anti-crossings due to the coupling of the confined states on upper and lower layers inside the blister. These spectra are layer localized where the respective confined states reside on either layer or equally distributed. For finite angular momentum, this layer localization can be at the edge of the blister and corresponds to degenerate modes of opposite momenta. Furthermore, the energy levels in GQB exhibit electron-hole symmetry that is sensitive to the electrostatic bias. Finally, we demonstrate that confinement in GQB persists even in the presence of a variation in the interlayer coupling. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000443135000001 |
Publication Date |
2018-08-13 |
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 |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
6 |
Open Access |
|
Notes |
; HMA and HB acknowledge the Saudi Center for Theoretical Physics (SCTP) for their generous support and the support of KFUPM under physics research group projects RG1502-1 and RG1502-2. This work is supported by the Flemish Science Foundation (FWO-Vl) by a post-doctoral fellowship (BVD). ; |
Approved |
Most recent IF: 2.649 |
Call Number |
UA @ lucian @ c:irua:153620UA @ admin @ c:irua:153620 |
Serial |
5086 |
Permanent link to this record |
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Author |
Li, H.; Bender, H.; Conard, T.; Maex, K.; Gutakovskii, A.; van Landuyt, J.; Froyen, L. |
Title |
Interaction of a Ti-capped Co thin film with Si3N4 |
Type |
A1 Journal article |
Year |
2000 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
77 |
Issue |
26 |
Pages |
4307-4309 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The reaction of a Ti (8 nm) capped Co film (15 nm) with a Si3N4 layer (150 nm) is studied after rapid thermal annealing at 660 degreesC for 120 s in a N-2 ambient. X-ray photoelectron spectroscopy, transmission electron microscopy, electron energy-loss spectroscopy, and Auger electron spectroscopy are used to study the reaction products. Combining the results of the different analyses yields a layer stack consisting of: TiO2/TiO/unreacted Co/(Ti,Co)(2)N/Co2Si, followed by amorphous Si3N4. The reaction mechanisms are discussed. Conclusions concerning the risk for degradation of nitride spacers in advanced devices are drawn. (C) 2000 American Institute of Physics. [S0003-6951(00)05248-7]. |
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 |
000166120500021 |
Publication Date |
2002-07-26 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
3 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.411; 2000 IF: 3.906 |
Call Number |
UA @ lucian @ c:irua:104225 |
Serial |
1683 |
Permanent link to this record |
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Author |
Berdiyorov, G.R.; Bahlouli, H.; Peeters, F.M. |
Title |
Theoretical study of electronic transport properties of a graphene-silicene bilayer |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
Volume |
117 |
Issue |
117 |
Pages |
225101 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Electronic transport properties of a graphene-silicene bilayer system are studied using density-functional theory in combination with the nonequilibrium Green's function formalism. Depending on the energy of the electrons, the transmission can be larger in this system as compared to the sum of the transmissions of separated graphene and silicene monolayers. This effect is related to the increased electron density of states in the bilayer sample. At some energies, the electronic states become localized in one of the layers, resulting in the suppression of the electron transmission. The effect of an applied voltage on the transmission becomes more pronounced in the layered sample as compared to graphene due to the larger variation of the electrostatic potential profile. Our findings will be useful when creating hybrid nanoscale devices where enhanced transport properties will be desirable. (C) 2015 AIP Publishing LLC. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000356176100040 |
Publication Date |
2015-06-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0021-8979;1089-7550; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.068 |
Times cited |
10 |
Open Access |
|
Notes |
; H. B. and F. M. P. acknowledge support from King Fahd University of Petroleum and Minerals, Saudi Arabia, under the RG1329-1 and RG1329-2 DSR Projects. ; |
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
Call Number |
c:irua:127075 |
Serial |
3611 |
Permanent link to this record |
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Author |
Abdullah, H.M.; Van der Donck, M.; Bahlouli, H.; Peeters, F.M.; Van Duppen, B. |
Title |
Graphene quantum blisters : a tunable system to confine charge carriers |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
112 |
Issue |
21 |
Pages |
213101 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Due to Klein tunneling, electrostatic confinement of electrons in graphene is not possible. This hinders the use of graphene for quantum dot applications. Only through quasi-bound states with finite lifetime has one achieved to confine charge carriers. Here, we propose that bilayer graphene with a local region of decoupled graphene layers is able to generate bound states under the application of an electrostatic gate. The discrete energy levels in such a quantum blister correspond to localized electron and hole states in the top and bottom layers. We find that this layer localization and the energy spectrum itself are tunable by a global electrostatic gate and that the latter also coincides with the electronic modes in a graphene disk. Curiously, states with energy close to the continuum exist primarily in the classically forbidden region outside the domain defining the blister. The results are robust against variations in size and shape of the blister which shows that it is a versatile system to achieve tunable electrostatic confinement in graphene. Published by AIP Publishing. |
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 |
000433140900025 |
Publication Date |
2018-05-22 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
9 |
Open Access |
|
Notes |
; H.M.A. and H.B. acknowledge the Saudi Center for Theoretical Physics (SCTP) for their generous support and the support of KFUPM under physics research group Project Nos. RG1502-1 and RG1502-2. This work was supported by the Flemish Science Foundation (FWO-Vl) by a post-doctoral fellowship (B.V.D.) and a doctoral fellowship (M.V.d.D.). ; |
Approved |
Most recent IF: 3.411 |
Call Number |
UA @ lucian @ c:irua:151505UA @ admin @ c:irua:151505 |
Serial |
5027 |
Permanent link to this record |
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Author |
Grimaud, A.; Iadecola, A.; Batuk, D.; Saubanere, M.; Abakumov, A.M.; Freeland, J.W.; Cabana, J.; Li, H.; Doublet, M.-L.; Rousse, G.; Tarascon, J.-M. |
Title |
Chemical activity of the peroxide/oxide redox couple : case study of Ba5Ru2O11 in aqueous and organic solvents |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
Volume |
30 |
Issue |
11 |
Pages |
3882-3893 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
The finding that triggering the redox activity of oxygen ions within the lattice of transition metal oxides can boost the performances of materials used in energy storage and conversion devices such as Li-ion batteries or oxygen evolution electrocatalysts has recently spurred intensive and innovative research in the field of energy. While experimental and theoretical efforts have been critical in understanding the role of oxygen nonbonding states in the redox activity of oxygen ions, a clear picture of the redox chemistry of the oxygen species formed upon this oxidation process is still missing. This can be, in part, explained by the complexity in stabilizing and studying these species once electrochemically formed. In this work, we alleviate this difficulty by studying the phase Ba5Ru2O11, which contains peroxide O-2(2-) groups, as oxygen evolution reaction electrocatalyst and Li-ion battery material. Combining physical characterization and electrochemical measurements, we demonstrate that peroxide groups can easily be oxidized at relatively low potential, leading to the formation of gaseous dioxygen and to the instability of the oxide. Furthermore, we demonstrate that, owing to the stabilization at high energy of peroxide, the high-lying energy of the empty sigma* antibonding O-O states limits the reversibility of the electrochemical reactions when the O-2(2-)/O2- redox couple is used as redox center for Li-ion battery materials or as OER redox active sites. Overall, this work suggests that the formation of true peroxide O-2(2-) states are detrimental for transition metal oxides used as OER catalysts and Li-ion battery materials. Rather, oxygen species with O-O bond order lower than 1 would be preferred for these applications. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
American Chemical Society |
Place of Publication |
Washington, D.C |
Editor |
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Language |
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Wos |
000435416600038 |
Publication Date |
2018-05-21 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0897-4756 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
9.466 |
Times cited |
2 |
Open Access |
Not_Open_Access |
Notes |
; We thank S. Belin of the ROCK beamline (financed by the French National Research Agency (ANR) as a part of the “Investissements d'Avenir” program, reference: ANR-10-EQPX-45; proposal no. 20160095) of synchrotron SOLEIL for her assistance during XAS measurements. Authors would also like to thank V. Nassif for her assistance on the D1B beamline. A.G, G.R, and J.-M.T. acknowledge funding from the European Research Council (ERC) (FP/2014)/ERC Grant Project 670116-ARPEMA. ; |
Approved |
Most recent IF: 9.466 |
Call Number |
UA @ lucian @ c:irua:151980 |
Serial |
5016 |
Permanent link to this record |
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Author |
Cornil, D.; Li, H.; Wood, C.; Pourtois, G.; Bredas, J.-L.; Cornil, J. |
Title |
Work-function modification of Au and Ag surfaces upon deposition of self-assembled monolayers : influence of the choice of the theoretical approach and the thiol decomposition scheme |
Type |
A1 Journal article |
Year |
2013 |
Publication |
ChemPhysChem : a European journal of chemical physics and physical chemistry |
Abbreviated Journal |
Chemphyschem |
Volume |
14 |
Issue |
13 |
Pages |
2939-2946 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
We have characterized theoretically the work-function modifications of the (111) surfaces of gold and silver upon deposition of self-assembled monolayers based on methanethiol and trifluoromethanethiol. A comparative analysis is made between the experimental results and those obtained from two widely used approaches based on density functional theory. The contributions to the total work-function modifications are estimated on the basis of two decomposition schemes of the thiol molecules that have been proposed in the literature. The contributions are found to differ significantly between the two approaches, as do the corresponding adsorption energies. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000324316000014 |
Publication Date |
2013-07-15 |
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 |
1439-4235; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.075 |
Times cited |
9 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.075; 2013 IF: 3.360 |
Call Number |
UA @ lucian @ c:irua:112278 |
Serial |
3923 |
Permanent link to this record |
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Author |
Armelao, L.; Bertagnolli, H.; Bleiner, D.; Groenewolt, M.; Gross, S.; Krishnan, V.; Sada, C.; Schubert, U.; Tondello, E.; Zattin, A. |
Title |
Highly dispersed mixed zirconia and hafnia nanoparticles in a silica matrix: First example of a ZrO2-HfO2-SiO2 ternary oxide system |
Type |
A1 Journal article |
Year |
2007 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
Volume |
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Issue |
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Pages |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
ZrO2 and HfO2 nanoparticles are homogeneously dispersed in SiO2 matrices (supported film and bulk powders) by copolymerization of two oxozirconium and oxohafnium clusters (M4O(2)(OMc)(12), M= Zr, Hf; OMc = OC(O)-C(CH3)=CH2) with (methacryloxypropyl)trimethoxysilane (MAPTMS, (CH2=C(CH3)C(O)O)-(CH2)(3)Si(OCH3)(3)). After calcination (at a temperature >= 800 degrees C), a silica matrix with homogeneously distributed MO2 nanocrystallites is obtained. This route yields a spatially homogeneous dispersion of the metal precursors inside the silica matrix, which is maintained during calcination. The composition of the films and the powders is studied before and after calcination by using Fourier transform infrared (FTIR) analysis, X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS), and laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS). The local environment of the metal atoms in one of the calcined samples is investigated by using X-ray Absorption Fine Structure (XAFS) spectroscopy. Through X-ray diffraction (XRD) the crystallization of Hf and Zr oxides is seen at temperatures higher than those expected for the pure oxides, and transmission electron microscopy (TEM) shows the presence of well-distributed and isolated crystalline oxide nanoparticles (540 nm). |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Weinheim |
Editor |
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Language |
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Wos |
000248062100011 |
Publication Date |
2007-05-29 |
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 |
1616-301x |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
12.124 |
Times cited |
34 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 12.124; 2007 IF: 7.496 |
Call Number |
UA @ lucian @ c:irua:95083 |
Serial |
4521 |
Permanent link to this record |