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Author Park, K.; De Beule, C.; Partoens, B. url  doi
openurl 
  Title The ageing effect in topological insulators : evolution of the surface electronic structure of Bi2Se3 upon K adsorption Type A1 Journal article
  Year 2013 Publication New journal of physics Abbreviated Journal New J Phys  
  Volume 15 Issue Pages 113031-16  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Topological insulators (TIs) have attracted a lot of interest in recent years due to their topologically protected surface states, as well as exotic proximity-induced phenomena and device applications for TI heterostructures. Since the first experimental studies of TIs, angle-resolved photoemission spectra (ARPES) showed that the electronic structure of the topological surface states significantly changes as a function of time after cleavage. The origin and underlying mechanism of this ageing effect are still under debate, despite its importance. Here we investigate the evolution of the surface Dirac cone for Bi2Se3 films upon asymmetric potassium (K) adsorption, using density-functional theory and a tight-binding model. We find that the K adatoms induce short-ranged downward band bending within 2-3 nm from the surface, due to charge transfer from the adatoms to the TI. These findings are in contrast to earlier proposals in the literature, that propose a long-ranged downward band bending up to 15 nm from the surface. Furthermore, as the charge transfer increases, we find that a new Dirac cone, localized slightly deeper into the TI than the original one, appears at the K-adsorbed surface, originating from strong Rashba-split conduction-band states. Our results suggest possible reinterpretations of experiments because the new Dirac cone might have been observed in ARPES measurements instead of the original one that appears immediately after cleavage. Our findings are consistent with ARPES data and provide insight into building TI-heterostructure devices by varying the band-bending potential or film thickness.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos (up) 000326876100006 Publication Date 2013-11-13  
  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 45 Open Access  
  Notes ; KP was supported by National Science Foundation grant numbers DMR-0804665 and DMR-1206354 and SDSC Trestles under DMR060009N. CDB was supported by the Research Foundation Flanders (FWO). ; Approved Most recent IF: 3.786; 2013 IF: 3.671  
  Call Number UA @ lucian @ c:irua:112707 Serial 84  
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Author Čukarić, N.A.; Tadić, M.Z.; Partoens, B.; Peeters, F.M. url  doi
openurl 
  Title 30-band k\cdot p model of electron and hole states in silicon quantum wells Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 88 Issue 20 Pages 205306  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We modeled the electron and hole states in Si/SiO2 quantum wells within a basis of standing waves using the 30-band k . p theory. The hard-wall confinement potential is assumed, and the influence of the peculiar band structure of bulk silicon on the quantum-well sub-bands is explored. Numerous spurious solutions in the conduction-band and valence-band energy spectra are found and are identified to be of two types: (1) spurious states which have large contributions of the bulk solutions with large wave vectors (the high-k spurious solutions) and (2) states which originate mainly from the spurious valley outside the Brillouin zone (the extravalley spurious solutions). An algorithm to remove all those nonphysical solutions from the electron and hole energy spectra is proposed. Furthermore, slow and oscillatory convergence of the hole energy levels with the number of basis functions is found and is explained by the peculiar band mixing and the confinement in the considered quantum well. We discovered that assuming the hard-wall potential leads to numerical instability of the hole states computation. Nonetheless, allowing the envelope functions to exponentially decay in a barrier of finite height is found to improve the accuracy of the computed hole states.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000327161500007 Publication Date 2013-11-20  
  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 10 Open Access  
  Notes ; This work was supported by the Ministry of Education, Science, and Technological Development of Serbia, the Belgian Science Policy (IAP), the Flemish fund for Scientific Research (FWO-Vl), and the Methusalem programme of the Flemish government. ; Approved Most recent IF: 3.836; 2013 IF: 3.664  
  Call Number UA @ lucian @ c:irua:112704 Serial 18  
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Author Petrovic, M.D.; Peeters, F.M.; Chaves, A.; Farias, G.A. pdf  doi
openurl 
  Title Conductance maps of quantum rings due to a local potential perturbation Type A1 Journal article
  Year 2013 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 25 Issue 49 Pages 495301-495309  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We performed a numerical simulation of the dynamics of a Gaussian shaped wavepacket inside a small sized quantum ring, smoothly connected to two leads and exposed to a perturbing potential of a biased atomic force microscope tip. Using the Landauer formalism, we calculated conductance maps of this system in the case of single and two subband transport. We explain the main features in the conductance maps as due to the AFM tip influence on the wavepacket phase and amplitude. In the presence of an external magnetic field, the tip modifies the phi(0) periodic Aharonov-Bohm oscillation pattern into a phi(0)/2 periodic Al'tshuler-Aronov-Spivak oscillation pattern. Our results in the case of multiband transport suggest tip selectivity to higher subbands, making them more observable in the total  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos (up) 000327181400002 Publication Date 2013-11-01  
  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 12 Open Access  
  Notes ; This work was supported by the Methusalem programme of the Flemish government, the CNPq-FWO bilateral programme and PNPD and FUNCAP/PRONEX grants. ; Approved Most recent IF: 2.649; 2013 IF: 2.223  
  Call Number UA @ lucian @ c:irua:112694 Serial 478  
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Author Krstajić, P.M.; Van Duppen, B.; Peeters, F.M. url  doi
openurl 
  Title Plasmons and their interaction with electrons in trilayer graphene Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 88 Issue 19 Pages 195423  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The interaction between electrons and plasmons in trilayer graphene is investigated within the Overhauser approach resulting in the “plasmaron” quasiparticle. This interaction is cast into a field theoretical problem, and its effect on the energy spectrum is calculated using improved Wigner-Brillouin perturbation theory. The plasmaron spectrum is shifted with respect to the bare electron spectrum by ΔE(k)∼150−200meV for ABC stacked trilayer graphene and for ABA trilayer graphene by ΔE(k)∼30−150 meV[ ΔE(k) ∼1 −5meV] for the hyperbolic (linear) part of the spectrum. The shift in general increases with the electron concentration and electron momentum. The dispersion of plasmarons is more pronounced in ABC stacked than in ABA stacked trilayer graphene, because of the different energy band structure and their different plasmon dispersion.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000327239200003 Publication Date 2013-11-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1098-0121 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 10 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), by the ESF-EuroGRAPHENE project CON-GRAN, and by the Serbian Ministry of Education and Science, within the Project No. TR 32008. ; Approved Most recent IF: 3.836; 2013 IF: 3.664  
  Call Number CMT @ cmt @ c:irua:112702 Serial 4489  
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Author Berdiyorov, G.R.; Savel'ev, S.E.; Kusmartsev, F.V.; Peeters, F.M. pdf  doi
openurl 
  Title In-phase motion of Josephson vortices in stacked SNS Josephson junctions : effect of ordered pinning Type A1 Journal article
  Year 2013 Publication Superconductor science and technology Abbreviated Journal Supercond Sci Tech  
  Volume 26 Issue 12 Pages 125010-125016  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The dynamics of Josephson vortices (fluxons) in artificial stacks of superconducting-normal-superconducting Josephson junctions is investigated using the anisotropic time-dependent Ginzburg-Landau theory in the presence of a square/rectangular array of pinning centers (holes). For small values of the applied drive, fluxons in different junctions move out of phase, forming a periodic triangular lattice. A rectangular lattice of moving fluxons is observed at larger currents, which is in agreement with previous theoretical predictions (Koshelev and Aranson 2000 Phys. Rev. Lett. 85 3938). This 'superradiant' flux-flow state is found to be stable in a wide region of applied current. The stability range of this ordered state is considerably larger than the one obtained for the pinning-free sample. Clear commensurability features are observed in the current-voltage characteristics of the system with pronounced peaks in the critical current at (fractional) matching fields. The effect of density and strength of the pinning centers on the stability of the rectangular fluxon lattice is discussed. Predicted synchronized motion of fluxons in the presence of ordered pinning can be detected experimentally using the rf response of the system, where enhancement of the Shapiro-like steps is expected due to the synchronization.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos (up) 000327447200013 Publication Date 2013-10-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-2048;1361-6668; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.878 Times cited 5 Open Access  
  Notes ; This work was supported by EU Marie Curie (Project No: 253057) and by the Flemish Science Foundation (FWO-Vl). ; Approved Most recent IF: 2.878; 2013 IF: 2.796  
  Call Number UA @ lucian @ c:irua:112834 Serial 1573  
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Author de Backer, J.; Vos, W.; Van Holsbeke, C.; Vinchurkar, S.; Claes, R.; Parizel, P.M.; de Backer, W. url  doi
openurl 
  Title Effect of high-dose N-acetylcysteine on airway geometry, inflammation, and oxidative stress in COPD patients Type A1 Journal article
  Year 2013 Publication International Journal Of Chronic Obstructive Pulmonary Disease Abbreviated Journal Int J Chronic Obstr  
  Volume 8 Issue Pages 569-579  
  Keywords A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP)  
  Abstract Background: Previous studies have demonstrated the potential beneficial effect of N-acetylcysteine (NAC) in chronic obstructive pulmonary disease (COPD). However, the required dose and responder phenotype remain unclear. The current study investigated the effect of high-dose NAC on airway geometry, inflammation, and oxidative stress in COPD patients. Novel functional respiratory imaging methods combining multislice computed tomography images and computer-based flow simulations were used with high sensitivity for detecting changes induced by the therapy. Methods: Twelve patients with Global Initiative for Chronic Obstructive Lung Disease stage II COPD were randomized to receive NAC 1800 mg or placebo daily for 3 months and were then crossed over to the alternative treatment for a further 3 months. Results: Significant correlations were found between image-based resistance values and glutathione levels after treatment with NAC (P = 0.011) and glutathione peroxidase at baseline (P = 0.036). Image-based resistance values appeared to be a good predictor for glutathione peroxidase levels after NAC (P = 0.02), changes in glutathione peroxidase levels (P = 0.035), and reduction in lobar functional residual capacity levels (P = 0.00084). In the limited set of responders to NAC therapy, the changes in airway resistance were in the same order as changes induced by budesonide/formoterol. Conclusion: A combination of glutathione, glutathione peroxidase, and imaging parameters could potentially be used to phenotype COPD patients who would benefit from addition of NAC to their current therapy. The findings of this small pilot study need to be confirmed in a larger pivotal trial.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000327537300001 Publication Date 2013-11-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1178-2005; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.157 Times cited 21 Open Access  
  Notes ; JDB is a founder/shareholder of FluidDA NV, Kontich, Belgium. WV, SV, and CVH are employed by FluidDA NV, and WDB is the director of FluidDA NV. PMP and RC have no conflicts of interest to report. The study was supported by Zambon SpA, Bresso, Italy. ; Approved Most recent IF: 3.157; 2013 IF: NA  
  Call Number UA @ lucian @ c:irua:112799 Serial 813  
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Author Berdiyorov, G.R.; Peeters, F.M. doi  openurl
  Title Influence of vacancy defects on the thermal stability of silicene: a reactive molecular dynamics study Type A1 Journal article
  Year 2014 Publication RSC advances Abbreviated Journal Rsc Adv  
  Volume 4 Issue 3 Pages 1133-1137  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The effect of vacancy defects on the structural properties and the thermal stability of free standing silicene – a buckled structure of hexagonally arranged silicon atoms – is studied using reactive molecular dynamics simulations. Pristine silicene is found to be stable up to 1500 K, above which the system transits to a three-dimensional amorphous configuration. Vacancy defects result in local structural changes in the system and considerably reduce the thermal stability of silicene: depending on the size of the vacancy defect, the critical temperature decreases by more than 30%. However, the system is still found to be stable well above room temperature within our simulation time of 500 ps. We found that the, stability of silicene can be increased by saturating the dangling bonds at the defect edges by foreign atoms (e.g., hydrogen).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000327868400015 Publication Date 2013-11-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2046-2069; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.108 Times cited 62 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. The authors are grateful to Prof. Adri van Duin for his support with the ReaxFF force field. ; Approved Most recent IF: 3.108; 2014 IF: 3.840  
  Call Number UA @ lucian @ c:irua:112829 Serial 1658  
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Author Muñoz, W.A.; Covaci, L.; Peeters, F.M. pdf  url
doi  openurl
  Title Superconducting current and proximity effect in ABA and ABC multilayer graphene Josephson junctions Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 88 Issue 88 Pages 214502  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using a numerical tight-binding approach based on the Chebyshev–Bogoliubov–de Gennes method we describe Josephson junctions made of multilayer graphene contacted by top superconducting gates. Both Bernal (ABA) and rhombohedral (ABC) stacking are considered and we find that the type of stacking has a strong effect on the proximity effect and the supercurrent flow. For both cases the pair amplitude shows a polarization between dimer and nondimer atoms, being more pronounced for rhombohedral stacking. Even though the proximity effect in nondimer sites is enhanced when compared to single-layer graphene, we find that the supercurrent is suppressed. The spatial distribution of the supercurrent shows that for Bernal stacking the current flows only in the topmost layers while for rhombohedral stacking the current flows throughout the whole structure.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000328569900004 Publication Date 2013-12-02  
  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 4 Open Access  
  Notes This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem funding of the Flemish Government Approved Most recent IF: 3.836; 2013 IF: 3.664  
  Call Number CMT @ cmt @ c:irua:128896 Serial 3962  
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Author Milovanović, S.P.; Masir, M.R.; Peeters, F.M. pdf  doi
openurl 
  Title Spectroscopy of snake states using a graphene Hall bar Type A1 Journal article
  Year 2013 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 103 Issue 23 Pages 233502-233504  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract An approach to observe snake states in a graphene Hall bar containing a pn-junction is proposed. The magnetic field dependence of the bend resistance in a ballistic graphene Hall bar structure containing a tilted pn-junction oscillates as a function of applied magnetic field. We show that each oscillation is due to a specific snake state that moves along the pn-interface. Furthermore, depending on the value of the magnetic field and applied potential, we can control the lead in which the electrons will end up and hence control the response of the system.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos (up) 000328634900090 Publication Date 2013-12-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 15 Open Access  
  Notes This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN and the Methusalem Foundation of the Flemish government. Approved Most recent IF: 3.411; 2013 IF: 3.515  
  Call Number UA @ lucian @ c:irua:113710 Serial 3074  
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Author de Sousa, A.A.; Chaves, A.; Farias, G.A.; Peeters, F.M. url  doi
openurl 
  Title Braess paradox at the mesoscopic scale Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 88 Issue 24 Pages 245417-6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We theoretically demonstrate that the transport inefficiency recently found experimentally for branched-out mesoscopic networks can also be observed in a quantum ring of finite width with an attached central horizontal branch. This is done by investigating the time evolution of an electron wave packet in such a system. Our numerical results show that the conductivity of the ring does not necessary improve if one adds an extra channel. This ensures that there exists a quantum analog of the Braess paradox, originating from quantum scattering and interference.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000328680500011 Publication Date 2013-12-17  
  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 financially supported by PRONEX/CNPq/FUNCAP and the bilateral project CNPq-FWO. Discussions with J. S. Andrade, Jr. are gratefully acknowledged. A. A. S. has been financially supported by CAPES, under PDSE Contract No. BEX 7177/13-5. ; Approved Most recent IF: 3.836; 2013 IF: 3.664  
  Call Number UA @ lucian @ c:irua:113705 Serial 253  
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Author Van Duppen, B.; Peeters, F.M. url  doi
openurl 
  Title Thermodynamic properties of the electron gas in multilayer graphene in the presence of a perpendicular magnetic field Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 88 Issue 24 Pages 245429-7  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The thermodynamic properties of the electron gas in multilayer graphene depend strongly on the number of layers and the type of stacking. Here we analyze how those properties change when we vary the number of layers for rhombohedral stacked multilayer graphene and compare our results with those from a conventional two-dimensional electron gas. We show that the highly degenerate zero-energy Landau level which is partly filled with electrons and partly with holes has a strong influence on the values of the different thermodynamic quantities.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000328686900006 Publication Date 2014-01-09  
  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 2 Open Access  
  Notes ; The authors would like to thank C. De Beule for enlightening discussions. This work was supported by the European Science Foundation (ESF) under the EUROCORES Program Euro-GRAPHENE within the project CONGRAN, the Flemish Science Foundation (FWO-Vl) by an aspirant research grant to B.V.D., and the Methusalem Program of the Flemish Government. ; Approved Most recent IF: 3.836; 2013 IF: 3.664  
  Call Number UA @ lucian @ c:irua:113700 Serial 3635  
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Author Zarenia, M.; Partoens, B.; Chakraborty, T.; Peeters, F.M. url  doi
openurl 
  Title Electron-electron interactions in bilayer graphene quantum dots Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 88 Issue 24 Pages 245432-245435  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract A parabolic quantum dot (QD) as realized by biasing nanostructured gates on bilayer graphene is investigated in the presence of electron-electron interaction. The energy spectrum and the phase diagram reveal unexpected transitions as a function of a magnetic field. For example, in contrast to semiconductor QDs, we find a valley transition rather than only the usual singlet-triplet transition in the ground state of the interacting system. The origin of these features can be traced to the valley degree of freedom in bilayer graphene. These transitions have important consequences for cyclotron resonance experiments.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000328688600010 Publication Date 2014-01-09  
  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 29 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES program EuroGRAPHENE (project CONGRAN), and the Methusalem foundation of the Flemish Government. T. C. is supported by the Canada Research Chairs program of the Government of Canada. ; Approved Most recent IF: 3.836; 2013 IF: 3.664  
  Call Number UA @ lucian @ c:irua:113698 Serial 926  
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Author Vos, W.; de Backer, J.; Poli, G.; De Volder, A.; Ghys, L.; Van Holsbeke, C.; Vinchurkar, S.; De Backer, L.; de Backer, W. pdf  doi
openurl 
  Title Novel functional imaging of changes in small airways of patients treated with extrafine beclomethasone/formoterol Type A1 Journal article
  Year 2013 Publication Respiration Abbreviated Journal Respiration  
  Volume 86 Issue 5 Pages 393-401  
  Keywords A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP)  
  Abstract Background: Inhaled formulations using extrafine particles of long-acting beta(2)-agonists and corticosteroids were developed to optimize asthma treatment. Findings that these combinations reach and treat smaller airways more effectively are predominantly based on general non-specific outcomes with little information on regional characteristics. Objectives: This study aims to assess long-term effects of extrafine beclomethasone/formoterol on small airways of asthmatic patients using novel functional imaging methods. Methods: Twenty-four stable asthma patients were subdivided into three groups (steroid naive, n = 7; partially controlled, n = 6; well controlled, n = 11). Current treatment was switched to a fixed combination of extrafine beclomethasone/formoterol (Foster (R); Chiesi Pharmaceuticals, Parma, Italy). Patients underwent lung function evaluation and thorax high-resolution computerized tomography (HRCT) scan. Local airway resistance was obtained from computational fluid dynamics (CFD). Results: After 6 months, the entire population showed improvement in pre-bronchodilation imaging parameters, including small airway volume (p = 0.0007), resistance (p = 0.011), and asthma control score (p = 0.016). Changes in small airway volume correlated with changes in asthma control score (p = 0.004). Forced expiratory volume in 1 s (p = 0.044) and exhaled nitric oxide (p = 0.040) also improved. Functional imaging provided more detail and clinical relevance compared to lung function tests, especially in the well-controlled group where only functional imaging parameters showed significant improvement, while the correlation with asthma control score remained. Conclusions: Extrafine beclomethasone/formoterol results in a significant reduction of small airway obstruction, detectable by functional imaging (HRCT/CFD). Changes in imaging parameters correlated significantly with clinically relevant improvements. This indicates that functional imaging is a useful tool for sensitive assessment of changes in the respiratory system after asthma treatment. Copyright (C) 2013 S. Karger AG, Basel  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Basel Editor  
  Language Wos (up) 000329046200006 Publication Date 2013-04-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1423-0356;0025-7931; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.772 Times cited 30 Open Access  
  Notes ; ; Approved Most recent IF: 2.772; 2013 IF: 2.924  
  Call Number UA @ lucian @ c:irua:113762 Serial 2376  
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Author Masir, M.R.; Moldovan, D.; Peeters, F.M. pdf  doi
openurl 
  Title Pseudo magnetic field in strained graphene : revisited Type A1 Journal article
  Year 2013 Publication Solid state communications Abbreviated Journal Solid State Commun  
  Volume 175 Issue Pages 76-82  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We revisit the theory of the pseudo magnetic field as induced by strain in graphene using the tight- binding approach. A systematic expansion of the hopping parameter and the deformation of the lattice vectors is presented from which we obtain an expression for the pseudo magnetic field for low energy electrons. We generalize and discuss previous results and propose a novel effective Hamiltonian. The contributions of the different terms to the pseudo field expression are investigated for a model triaxial strain profile and are compared with the full solution. Our work suggests that the previous proposed pseudo magnetic field expression is valid up to reasonably high strain (15%) and there is no K-dependent pseudo-magnetic field.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos (up) 000329538200010 Publication Date 2013-04-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0038-1098; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.554 Times cited 57 Open Access  
  Notes This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EURO- CORES Program EuroGRAPHENE within the project CONGRAN and the Methusalem programme of the Flemish government. Approved Most recent IF: 1.554; 2013 IF: 1.698  
  Call Number UA @ lucian @ c:irua:114805 Serial 2737  
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Author Amini, M.N.; Dixit, H.; Saniz, R.; Lamoen, D.; Partoens, B. pdf  doi
openurl 
  Title The origin of p-type conductivity in ZnM2O4 (M = Co, Rh, Ir) spinels Type A1 Journal article
  Year 2014 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 16 Issue 6 Pages 2588-2596  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract ZnM2O4 (M = Co, Rh, Ir) spinels are considered as a class of potential p-type transparent conducting oxides (TCOs). We report the formation energy of acceptor-like defects using first principles calculations with an advanced hybrid exchange-correlation functional (HSE06) within density functional theory (DFT). Due to the discrepancies between the theoretically obtained band gaps with this hybrid functional and the – scattered – experimental results, we also perform GW calculations to support the validity of the description of these spinels with the HSE06 functional. The considered defects are the cation vacancy and antisite defects, which are supposed to be the leading source of disorder in the spinel structures. We also discuss the band alignments in these spinels. The calculated formation energies indicate that the antisite defects ZnM (Zn replacing M, M = Co, Rh, Ir) and VZn act as shallow acceptors in ZnCo2O4, ZnRh2O4 and ZnIr2O4, which explains the experimentally observed p-type conductivity in those systems. Moreover, our systematic study indicates that the ZnIr antisite defect has the lowest formation energy in the group and it corroborates the highest p-type conductivity reported for ZnIr2O4 among the group of ZnM2O4 spinels. To gain further insight into factors affecting the p-type conductivity, we have also investigated the formation of localized small polarons by calculating the self-trapping energy of the holes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge Editor  
  Language Wos (up) 000329926700040 Publication Date 2013-12-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076;1463-9084; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.123 Times cited 47 Open Access  
  Notes Fwo; Goa; Hercules Approved Most recent IF: 4.123; 2014 IF: 4.493  
  Call Number UA @ lucian @ c:irua:114829 Serial 2525  
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Author Neek-Amal, M.; Sadeghi, A.; Berdiyorov, G.R.; Peeters, F.M. doi  openurl
  Title Realization of free-standing silicene using bilayer graphene Type A1 Journal article
  Year 2013 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 103 Issue 26 Pages 261904-4  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The available synthesized silicene-like structures have been only realized on metallic substrates which are very different from the standalone buckled silicene, e. g., the Dirac cone of silicene is destroyed due to lattice distortion and the interaction with the substrate. Using graphene bilayer as a scaffold, a route is proposed to synthesize silicene with electronic properties decoupled from the substrate. The buckled hexagonal arrangement of silicene between the graphene layers is found to be very similar to the theoretically predicted standalone buckled silicene which is only very weakly van der Waals coupled to the graphene layers with a graphite-like interlayer distance of 3.42 angstrom and without any lattice distortion. We found that these stacked layers are stable well above room temperature. (C) 2013 AIP Publishing LLC.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos (up) 000329977400022 Publication Date 2013-12-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951;1077-3118; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 74 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. M.N.-A. was supported by the EU-Marie Curie IIF postdoc Fellowship/299855. ; Approved Most recent IF: 3.411; 2013 IF: 3.515  
  Call Number UA @ lucian @ c:irua:114849 Serial 2837  
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Author Nasr Esfahani, D.; Covaci, L.; Peeters, F.M. pdf  doi
openurl 
  Title Surface correlation effects in two-band strongly correlated slabs Type A1 Journal article
  Year 2014 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 26 Issue 7 Pages 075601-75609  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using an extension of the Gutzwiller approximation for an inhomogeneous system, we study the two-band Hubbard model with unequal band widths for a slab geometry. The aim is to investigate the mutual effect of individual bands on the spatial distribution of quasi-particle weight and charge density, especially near the surface of the slab. The main effect of the difference in band width is the presence of two different length scales corresponding to the quasi-particle profile of each band. This is enhanced in the vicinity of the critical interaction of the narrow band where an orbitally selective Mott transition occurs and a surface dead layer forms for the narrow band. For the doped case, two different regimes of charge transfer between the surface and the bulk of the slab are revealed. The charge transfer from surface/ center to center/ surface depends on both the doping level and the average relative charge accumulated in each band. Such effects could also be of importance when describing the accumulation of charges at the interface between structures made of multi-band strongly correlated materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos (up) 000330719500009 Publication Date 2014-01-29  
  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 1 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program of the Flemish government. One of us (LC) is a postdoctoral fellow of the FWO-Vl. ; Approved Most recent IF: 2.649; 2014 IF: 2.346  
  Call Number UA @ lucian @ c:irua:115723 Serial 3395  
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Author Van Holsbeke, C.S.; Verhulst, S.L.; Vos, W.G.; de Backer, J.W.; Vinchurkar, S.C.; Verdonck, P.R.; van Doorn, J.W.D.; Nadjmi, N.; de Backer, W.A. doi  openurl
  Title Change in upper airway geometry between upright and supine position during tidal nasal breathing Type A1 Journal article
  Year 2014 Publication Journal Of Aerosol Medicine And Pulmonary Drug Delivery Abbreviated Journal J Aerosol Med Pulm D  
  Volume 27 Issue 1 Pages 51-57  
  Keywords A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP); Translational Neurosciences (TNW)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000331144500007 Publication Date 2013-03-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1941-2711;1941-2703; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.528 Times cited 16 Open Access  
  Notes ; ; Approved Most recent IF: 2.528; 2014 IF: 2.798  
  Call Number UA @ lucian @ c:irua:115759 Serial 308  
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Author Neek-Amal, M.; Peeters, F.M. doi  openurl
  Title Graphene on boron-nitride : Moiré pattern in the van der Waals energy Type A1 Journal article
  Year 2014 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 104 Issue 4 Pages 041909-4  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The spatial dependence of the van der Waals (vdW) energy between graphene and hexagonal boron-nitride (h-BN) is investigated using atomistic simulations. The van der Waals energy between graphene and h-BN shows a hexagonal superlattice structure identical to the observed Moire pattern in the local density of states, which depends on the lattice mismatch and misorientation angle between graphene and h-BN. Our results provide atomistic features of the weak van der Waals interaction between graphene and BN which are in agreement with experiment and provide an analytical expression for the size of the spatial variation of the weak van der Waals interaction. We also found that the A-B-lattice symmetry of graphene is broken along the armchair direction. (C) 2014 AIP Publishing LLC.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos (up) 000331209900028 Publication Date 2014-01-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6951;1077-3118; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.411 Times cited 61 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. M.N.-A was supported by the EU-Marie Curie IIF postdoctoral Fellowship/299855. ; Approved Most recent IF: 3.411; 2014 IF: 3.302  
  Call Number UA @ lucian @ c:irua:115802 Serial 1374  
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Author Milovanović, S.P.; Masir, M.R.; Peeters, F.M. pdf  doi
openurl 
  Title Magnetic electron focusing and tuning of the electron current with a pn-junction Type A1 Journal article
  Year 2014 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 115 Issue 4 Pages 043719-6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Transverse magnetic focusing properties of graphene using a ballistic four terminal structure are investigated. The electric response is obtained using the semiclassical billiard model. The transmission exhibits pronounced peaks as a consequence of skipping orbits at the edge of the structure. When we add a pn-junction between the two probes, snake states along the pn-interface appear. Injected electrons are guided by the pn-interface to one of the leads depending on the value of the applied magnetic field. Oscillations in the resistance are found depending on the amount of particles that end up in each lead.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos (up) 000331210800066 Publication Date 2014-01-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 21 Open Access  
  Notes This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN, and the Methusalem Foundation of the Flemish government. Approved Most recent IF: 2.068; 2014 IF: 2.183  
  Call Number UA @ lucian @ c:irua:115801 Serial 1866  
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Author Kao, K.-H.; Verhulst, A.S.; Van de Put, M.; Vandenberghe, W.G.; Sorée, B.; Magnus, W.; De Meyer, K. doi  openurl
  Title Tensile strained Ge tunnel field-effect transistors: k\cdot p material modeling and numerical device simulation Type A1 Journal article
  Year 2014 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 115 Issue 4 Pages 044505-44508  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Group IV based tunnel field-effect transistors generally show lower on-current than III-V based devices because of the weaker phonon-assisted tunneling transitions in the group IV indirect bandgap materials. Direct tunneling in Ge, however, can be enhanced by strain engineering. In this work, we use a 30-band k.p method to calculate the band structure of biaxial tensile strained Ge and then extract the bandgaps and effective masses at Gamma and L symmetry points in k-space, from which the parameters for the direct and indirect band-to-band tunneling (BTBT) models are determined. While transitions from the heavy and light hole valence bands to the conduction band edge at the L point are always bridged by phonon scattering, we highlight a new finding that only the light-holelike valence band is strongly coupling to the conduction band at the Gamma point even in the presence of strain based on the 30-band k.p analysis. By utilizing a Technology Computer Aided Design simulator equipped with the calculated band-to-band tunneling BTBT models, the electrical characteristics of tensile strained Ge point and line tunneling devices are self-consistently computed considering multiple dynamic nonlocal tunnel paths. The influence of field-induced quantum confinement on the tunneling onset is included. Our simulation predicts that an on-current up to 160 (260) mu A/mu m can be achieved along with on/off ratio > 10(6) for V-DD = 0.5V by the n-type (p-type) line tunneling device made of 2.5% biaxial tensile strained Ge. (C) 2014 AIP Publishing LLC.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos (up) 000331210800113 Publication Date 2014-01-26  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 26 Open Access  
  Notes ; Authors would like to thank Dr. Mohammad Ali Pourghaderi for useful discussions on the nonparabolicity. Authors would also like to thank Professor Eddy Simoen and Dr. Yosuke Shimura for useful discussions about the validity of modeled bandgaps and effective masses. This work was also supported by IMEC's Industrial Affiliation Program. ; Approved Most recent IF: 2.068; 2014 IF: 2.183  
  Call Number UA @ lucian @ c:irua:115800 Serial 3505  
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Author Verreck, D.; Van de Put, M.; Sorée, B.; Verhulst, A.S.; Magnus, W.; Vandenberghe, W.G.; Collaert, N.; Thean, A.; Groeseneken, G. doi  openurl
  Title Quantum mechanical solver for confined heterostructure tunnel field-effect transistors Type A1 Journal article
  Year 2014 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 115 Issue 5 Pages 053706-53708  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Heterostructure tunnel field-effect transistors (HTFET) are promising candidates for low-power applications in future technology nodes, as they are predicted to offer high on-currents, combined with a sub-60 mV/dec subthreshold swing. However, the effects of important quantum mechanical phenomena like size confinement at the heterojunction are not well understood, due to the theoretical and computational difficulties in modeling realistic heterostructures. We therefore present a ballistic quantum transport formalism, combining a novel envelope function approach for semiconductor heterostructures with the multiband quantum transmitting boundary method, which we extend to 2D potentials. We demonstrate an implementation of a 2-band version of the formalism and apply it to study confinement in realistic heterostructure diodes and p-n-i-n HTFETs. For the diodes, both transmission probabilities and current densities are found to decrease with stronger confinement. For the p-n-i-n HTFETs, the improved gate control is found to counteract the deterioration due to confinement. (C) 2014 AIP Publishing LLC.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos (up) 000331645900040 Publication Date 2014-02-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979;1089-7550; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 15 Open Access  
  Notes ; D. Verreck acknowledges the support of a Ph.D. stipend from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen). This work was supported by imec's Industrial Affiliation Program. ; Approved Most recent IF: 2.068; 2014 IF: 2.183  
  Call Number UA @ lucian @ c:irua:115825 Serial 2780  
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Author Zarenia, M.; Vasilopoulos, P.; Pourtolami, N.; Peeters, F.M. url  doi
openurl 
  Title Landau-level dispersion and the quantum Hall plateaus in bilayer graphene Type P1 Proceeding
  Year 2013 Publication AIP conference proceedings Abbreviated Journal  
  Volume 1566 Issue Pages 275-276  
  Keywords P1 Proceeding; Condensed Matter Theory (CMT)  
  Abstract We study the quantum Hall effect (QHE) in bilayer graphene using the Kubo-Greenwood formula. At zero temperature the Hall conductivity sigma(yx) is given by sigma(yx) – 4(N + 1)e(2)/h with N the index of the highest occupied Landau level (LL). Including the dispersion of the LLs and their width, due to e. g. scattering by impurities, produces the plateau of the n = 0 LL in agreement with experimental results on doped samples and similar theoretical results on single-layer graphene plateaus widen with impurity concentration. Further, the evaluated resistivity rho(xx) exhibits a strong, oscillatory dependence on the electron concentration. Explicit results are obtained for delta-function impurities.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York Editor  
  Language Wos (up) 000331793000137 Publication Date 2014-01-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (project CONGRAN) and the Canadian NSERC Grant No. OGP0121756. ; Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:115871 Serial 1770  
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Author Ravi Kishore, V.V.; Partoens, B.; Peeters, F.M. pdf  doi
openurl 
  Title Electronic and optical properties of core-shell nanowires in a magnetic field Type A1 Journal article
  Year 2014 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 26 Issue 9 Pages 095501-95512  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The electronic and optical properties of zincblende nanowires are investigated in the presence of a uniform magnetic field directed along the [001] growth direction within the k . p method. We focus our numerical study on core-shell nanowires consisting of the III-V materials GaAs, AlxGa1-xAs and AlyGa1-y/0.51In0.49P. Nanowires with electrons confined in the core exhibit a Fock-Darwin-like spectrum, whereas nanowires with electrons confined in the shell show Aharonov-Bohm oscillations. Thus, by properly choosing the core and the shell materials of the nanowire, the optical properties in a magnetic field can be tuned in very different ways.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos (up) 000331954500006 Publication Date 2014-02-12  
  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 10 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish government. ; Approved Most recent IF: 2.649; 2014 IF: 2.346  
  Call Number UA @ lucian @ c:irua:115845 Serial 998  
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Author Singh, S.K.; Neek-Amal, M.; Peeters, F.M. pdf  doi
openurl 
  Title Electronic properties of graphene nano-flakes : energy gap, permanent dipole, termination effect, and Raman spectroscopy Type A1 Journal article
  Year 2014 Publication The journal of chemical physics Abbreviated Journal J Chem Phys  
  Volume 140 Issue 7 Pages 074304-74309  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The electronic properties of graphene nano-flakes (GNFs) with different edge passivation are investigated by using density functional theory. Passivation with F and H atoms is considered: C-Nc X-Nx (X = F or H). We studied GNFs with 10 < N-c < 56 and limit ourselves to the lowest energy configurations. We found that: (i) the energy difference Delta between the highest occupied molecular orbital and the lowest unoccupied molecular orbital decreases with N-c, (ii) topological defects (pentagon and heptagon) break the symmetry of the GNFs and enhance the electric polarization, (iii) the mutual interaction of bilayer GNFs can be understood by dipole-dipole interaction which were found sensitive to the relative orientation of the GNFs, (iv) the permanent dipoles depend on the edge terminated atom, while the energy gap is independent of it, and (v) the presence of heptagon and pentagon defects in the GNFs results in the largest difference between the energy of the spin-up and spin-down electrons which is larger for the H-passivated GNFs as compared to F-passivated GNFs. Our study shows clearly the effect of geometry, size, termination, and bilayer on the electronic properties of small GNFs. This study reveals important features of graphene nano-flakes which can be detected using Raman spectroscopy. (C) 2014 AIP Publishing LLC.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos (up) 000332039900020 Publication Date 2014-02-20  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-9606;1089-7690; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.965 Times cited 30 Open Access  
  Notes ; This work was supported by the EU-Marie Curie IIF postdoctoral Fellowship/ 299855 (for M. N.-A.), the ESF-EuroGRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-Vl), and the Methusalem Foundation of the Flemish Government. ; Approved Most recent IF: 2.965; 2014 IF: 2.952  
  Call Number UA @ lucian @ c:irua:115857 Serial 1002  
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Author Sobrino Fernandez, M.; Misko, V.R.; Peeters, F.M. url  doi
openurl 
  Title Self-assembly of Janus particles confined in a channel Type A1 Journal article
  Year 2014 Publication Physical review : E : statistical, nonlinear, and soft matter physics Abbreviated Journal Phys Rev E  
  Volume 89 Issue 2 Pages 022306-6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Janus particles present an important class of building blocks for directional assembly. These are compartmentalized colloids with two different hemispheres. Here, we consider a two-dimensional model of Janus disks consisting of a hydrophobic semicircle and an electro-negatively charged one. Placed in a solution, the hydrophobic sides will attract each other while the charged sides will give rise to a repulsive force. Using molecular dynamics simulations, we study the morphology of these particles when confined in a channel-like environment using a one dimensional harmonic confinement potential. The interest to this system is first of all due to the fact that it could serve as a simple model for membrane formation. Indeed, the recently synthesized new class of artificial amphiphiles, known as Janus dendrimers, were shown to self-assemble in bilayer structures mimicking biological membranes. In turn, Janus particles that combine the amphiphilicity and colloidal rigidity serve as a good model for Janus dendrimers. A variety of ordered membrane-like morphologies are found consisting of single and multiple chain configurations with different orientations of the particles with respect to each other that we summarize in a phase diagram.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication Woodbury (NY) Editor  
  Language Wos (up) 000332179900009 Publication Date 2014-02-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1539-3755;1550-2376; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.366 Times cited 11 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and by the “Odysseus” program of the Flemish government and FWO-Vl. ; Approved Most recent IF: 2.366; 2014 IF: 2.288  
  Call Number UA @ lucian @ c:irua:115858 Serial 2971  
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Author Singh, S.K.; Costamagna, S.; Neek-Amal, M.; Peeters, F.M. doi  openurl
  Title Melting of partially fluorinated graphene : from detachment of fluorine atoms to large defects and random coils Type A1 Journal article
  Year 2014 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 118 Issue 8 Pages 4460-4464  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract The melting of fluorographene is very unusual and depends strongly on the degree of fluorination. For temperatures below 1000 K, fully fluorinated graphene (FFG) is thermomechanically more stable than graphene but at T-m approximate to 2800 K FFG transits to random coils which is almost 2 times lower than the melting temperature of graphene, i.e., 5300 K. For fluorinated graphene up to 30% ripples causes detachment of individual F-atoms around 2000 K, while for 40%-60% fluorination large defects are formed beyond 1500 K and beyond 60% of fluorination F-atoms remain bonded to graphene until melting. The results agree with recent experiments on the dependence of the reversibility of the fluorination process on the percentage of fluorination.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos (up) 000332188100069 Publication Date 2014-01-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447; 1932-7455 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited 16 Open Access  
  Notes ; This work was supported by the EU-Marie Curie IIF postdoc Fellowship/299855 (for M.N.-A.), the ESF-Eurographene project CONGRAN, and the Flemish Science Foundation (FWO-VI). Financial support from the Collaborative program MINCyT (Argentina)-FWO(Belgium) is also acknowledged. ; Approved Most recent IF: 4.536; 2014 IF: 4.772  
  Call Number UA @ lucian @ c:irua:128874 Serial 4600  
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Author de Sena, S.H.R.; Pereira, J.M.; Peeters, F.M.; Farias, G.A. url  doi
openurl 
  Title Topological confinement in trilayer graphene Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 89 Issue 3 Pages 035420-35425  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We calculate the spectrum of states that are localized at the interface between two regions of opposite bias in trilayer graphene (TLG). These potential profiles, also known as potential kinks, have been predicted to support two different branches of localized states for the case of bilayer graphene, and show similarities to the surface states of topological insulators. On the other hand, we found that ABC stacked TLG exhibits three different unidimensional branches of states in each valley that are confined to the kink interface. They have the property E(k(y)) = -E(-k(y)) when belonging to the same valley and E-K(k(y)) = -E-K' (-k(y)). A kink-antikink potential profile opens a gap in the spectrum of these one-dimensional states.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000332220800005 Publication Date 2014-01-21  
  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 4 Open Access  
  Notes ; This work was supported by the Brazilian Council for Research (CNPq-PRONEX), the Flemish Science Foundation (FWO-Vl), and the Bilateral project between CNPq and FWO-Vl and the Brazilian program Science Without Borders (CsF). ; Approved Most recent IF: 3.836; 2014 IF: 3.736  
  Call Number UA @ lucian @ c:irua:115830 Serial 3676  
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Author Berdiyorov, G.R.; Neek-Amal, M.; Peeters, F.M.; van Duin, A.C.T. url  doi
openurl 
  Title Stabilized silicene within bilayer graphene : a proposal based on molecular dynamics and density-functional tight-binding calculations Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 89 Issue 2 Pages 024107-6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Freestanding silicene is predicted to display comparable electronic properties as graphene. However, the yet synthesized silicenelike structures have been only realized on different substrates which turned out to exhibit versatile crystallographic structures that are very different from the theoretically predicted buckled phase of freestanding silicene. This calls for a different approach where silicene is stabilized using very weakly interacting surfaces. We propose here a route by using graphene bilayer as a scaffold. The confinement between the flat graphene layers results in a planar clustering of Si atoms with small buckling, which is energetically unfavorable in vacuum. Buckled hexagonal arrangement of Si atoms similar to freestanding silicene is observed for large clusters, which, in contrast to Si atoms on metallic surfaces, is only very weakly van der Waals coupled to the graphene layers. These clusters are found to be stable well above room temperature. Our findings, which are supported by density-functional tight-binding calculations, show that intercalating bilayer graphene with Si is a favorable route to realize silicene.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000332226200002 Publication Date 2014-01-24  
  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 43 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. M.N.-A. was supported by the EU-Marie Curie IIF postdoc Fellowship/299855. One of us (F. M. P.) acknowledges discussions with Professor Hongjun Gao. G. R. B acknowledges the support of the King Fahd University of Petroleum and Minerals, Saudi Arabia, under the TPRG131-CS-15 DSR project. A.C.T.vD acknowledges funding from AFOSR Grants No. FA9550-10-1-0563 and No. FA9550-11-1-0158. ; Approved Most recent IF: 3.836; 2014 IF: 3.736  
  Call Number UA @ lucian @ c:irua:115829 Serial 3140  
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Author da Costa, D.R.; Chaves, A.; Zarenia, M.; Pereira, J.M.; Farias, G.A.; Peeters, F.M. url  doi
openurl 
  Title Geometry and edge effects on the energy levels of graphene quantum rings : a comparison between tight-binding and simplified Dirac models Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 89 Issue 7 Pages 075418-12  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We present a systematic study of the energy spectra of graphene quantum rings having different geometries and edge types in the presence of a perpendicular magnetic field. Results are obtained within the tight-binding (TB) and Dirac models and we discuss which features of the former can be recovered by using the approximations imposed by the latter. Energy levels of graphene quantum rings obtained by diagonalizing the TB Hamiltonian are demonstrated to be strongly dependent on the rings geometry and the microscopical structure of the edges. This makes it difficult to recover those spectra by the existing theories that are based on the continuum (Dirac) model. Nevertheless, our results show that both approaches (i.e., TB and Dirac model) may provide similar results, but only for very specific combinations of ring geometry and edge types. The results obtained by a simplified model describing an infinitely thin circular Dirac ring show good agreement with those obtained for hexagonal and rhombus armchair graphene rings within the TB model. Moreover, we show that the energy levels of a circular quantum ring with an infinite mass boundary condition obtained within the Dirac model agree with those for a ring defined by a ring-shaped staggered potential obtained within the TB model.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000332390000009 Publication Date 2014-02-18  
  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 56 Open Access  
  Notes ; This work was financially supported by CNPq, under Contract NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES Foundation under the process number BEX 7178/13-1, the Bilateral programme between CNPq and the Flemish Science Foundation (FWO-Vl), and the Brazilian Program Science Without Borders (CsF). ; Approved Most recent IF: 3.836; 2014 IF: 3.736  
  Call Number UA @ lucian @ c:irua:115823 Serial 1328  
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