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Author Annys, A.; Jannis, D.; Verbeeck, J.; Annys, A.; Jannis, D.; Verbeeck, J.
Title Deep learning for automated materials characterisation in core-loss electron energy loss spectroscopy Type A1 Journal article
Year 2023 Publication Scientific reports Abbreviated Journal
Volume 13 Issue 1 Pages 13724
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Electron energy loss spectroscopy (EELS) is a well established technique in electron microscopy that yields information on the elemental content of a sample in a very direct manner. One of the persisting limitations of EELS is the requirement for manual identification of core-loss edges and their corresponding elements. This can be especially bothersome in spectrum imaging, where a large amount of spectra are recorded when spatially scanning over a sample area. This paper introduces a synthetic dataset with 736,000 labeled EELS spectra, computed from available generalized oscillator strength tables, that represents 107 K, L, M or N core-loss edges and 80 chemical elements. Generic lifetime broadened peaks are used to mimic the fine structure due to band structure effects present in experimental core-loss edges. The proposed dataset is used to train and evaluate a series of neural network architectures, being a multilayer perceptron, a convolutional neural network, a U-Net, a residual neural network, a vision transformer and a compact convolutional transformer. An ensemble of neural networks is used to further increase performance. The ensemble network is used to demonstrate fully automated elemental mapping in a spectrum image, both by directly mapping the predicted elemental content and by using the predicted content as input for a physical model-based mapping.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001052937600046 Publication Date 2023-08-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record
Impact Factor 4.6 Times cited Open Access OpenAccess
Notes (down) A.A. would like to acknowledge the resources and services used in this work provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government. J.V. acknowledges the IMPRESS project. The IMPRESS project has received funding from the HORIZON EUROPE framework program for research and innovation under grant agreement n. 101094299. Approved Most recent IF: 4.6; 2023 IF: 4.259
Call Number UA @ admin @ c:irua:198647 Serial 8846
Permanent link to this record
 
 
Author Dixit, H.; Saniz, R.; Lamoen, D.; Partoens, B.
Title Accurate pseudopotential description of the GW bandstructure of ZnO Type A1 Journal article
Year 2011 Publication Computer physics communications Abbreviated Journal Comput Phys Commun
Volume 182 Issue 9 Pages 2029-2031
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract We present the GW band structure of ZnO in its wurtzite (WZ), zincblende (ZB) and rocksalt (RS) phases at the Γ point, calculated within the GW approximation. We have used a Zn20+ pseudopotential which is essential for the adequate treatment of the exchange interaction in the self-energy. The accuracy of the pseudopotential used is also discussed. The effect of the pd hybridization on the GW corrections to the band gap is correlated by comparing the ZB and RS phase.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000292675100062 Publication Date 2011-02-17
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0010-4655; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.936 Times cited 18 Open Access
Notes (down) ; ; Approved Most recent IF: 3.936; 2011 IF: 3.268
Call Number UA @ lucian @ c:irua:90761 Serial 51
Permanent link to this record
 
 
Author Van de Put, M.L.; Vandenberghe, W.G.; Magnus, W.; Sorée, B.
Title An envelope function formalism for lattice-matched heterostructures Type A1 Journal article
Year 2015 Publication Physica: B : condensed matter Abbreviated Journal Physica B
Volume 470-471 Issue 470-471 Pages 69-75
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The envelope function method traditionally employs a single basis set which, in practice, relates to a single material because the k.p matrix elements are generally only known in a particular basis. In this work, we defined a basis function transformation to alleviate this restriction. The transformation is completely described by the known inter-band momentum matrix elements. The resulting envelope function equation can solve the electronic structure in lattice matched heterostructures without resorting to boundary conditions at the interface between materials, while all unit-cell averaged observables can be calculated as with the standard envelope function formalism. In the case of two coupled bands, this heterostructure formalism is equivalent to the standard formalism while taking position dependent matrix elements. (C) 2015 Elsevier B.V. All rights reserved
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000355149600011 Publication Date 2015-04-26
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4526; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.386 Times cited 5 Open Access
Notes (down) ; ; Approved Most recent IF: 1.386; 2015 IF: 1.319
Call Number c:irua:126397 Serial 95
Permanent link to this record
 
 
Author Ludu, A.; Van Deun, J.; Milošević, M.V.; Cuyt, A.; Peeters, F.M.
Title Analytic treatment of vortex states in cylindrical superconductors in applied axial magnetic field Type A1 Journal article
Year 2010 Publication Journal of mathematical physics Abbreviated Journal J Math Phys
Volume 51 Issue 8 Pages 082903,1-082903,29
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We solve the linear GinzburgLandau (GL) equation in the presence of a uniform magnetic field with cylindrical symmetry and we find analytic expressions for the eigenfunctions in terms of the confluent hypergeometric functions. The discrete spectrum results from an implicit equation associated to the boundary conditions and it is resolved in analytic form using the continued fractions formalism. We study the dependence of the spectrum and the eigenfunctions on the sample size and the surface conditions for solid and hollow cylindrical superconductors. Finally, the solutions of the nonlinear GL formalism are constructed as expansions in the linear GL eigenfunction basis and selected by minimization of the free energy. We present examples of vortex states and their energies for different samples in enhancing/suppressing superconductivity surroundings.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000281905000026 Publication Date 2010-08-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0022-2488; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.077 Times cited 10 Open Access
Notes (down) ; ; Approved Most recent IF: 1.077; 2010 IF: 1.291
Call Number UA @ lucian @ c:irua:84880 Serial 106
Permanent link to this record
 
 
Author van Holsbeke, C.; de Backer, J.; Vos, W.; Verdonck, P.; van Ransbeeck, P.; Claessens, T.; Braem, M.; Vanderveken, O.; de Backer, W.
Title Anatomical and functional changes in the upper airways of sleep apnea patients due to mandibular repositioning: a large scale study Type A1 Journal article
Year 2011 Publication Journal of biomechanics Abbreviated Journal J Biomech
Volume 44 Issue 3 Pages 442-449
Keywords A1 Journal article; Condensed Matter Theory (CMT); Vision lab; Laboratory Experimental Medicine and Pediatrics (LEMP); Translational Neurosciences (TNW)
Abstract The obstructive sleep apnea-hypopnea syndrome (OSAHS) is a sleep related breathing disorder. A popular treatment is the use of a mandibular repositioning appliance (MRA) which advances the mandibula during the sleep and decreases the collapsibility of the upper airway. The success rate of such a device is, however, limited and very variable within a population of patients. Previous studies using computational fluid dynamics have shown that there is a decrease in upper airway resistance in patients who improve clinically due to an MRA. In this article, correlations between patient-specific anatomical and functional parameters are studied to examine how MRA induced biomechanical changes will have an impact on the upper airway resistance. Low-dose computed tomography (CT) scans are made from 143 patients suffering from OSAHS. A baseline scan and a scan after mandibular repositioning (MR) are performed in order to study variations in parameters. It is found that MR using a simulation bite is able to induce resistance changes by changing the pharyngeal lumen. The change in minimal cross-sectional area is the best parameter to predict the change in upper airway resistance. Looking at baseline values, the ideal patients for MR induced resistance decrease seem to be women with short airways, high initial resistance and no baseline occlusion.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000287551000014 Publication Date 2010-10-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-9290; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.664 Times cited 23 Open Access
Notes (down) ; ; Approved Most recent IF: 2.664; 2011 IF: 2.434
Call Number UA @ lucian @ c:irua:85305 Serial 112
Permanent link to this record
 
 
Author Ullah, S.; Hussain, A.; Syed, W.A.; Saqlain, M.A.; Ahmad, I.; Leenaerts, O.; Karim, A.
Title Band-gap tuning of graphene by Be doping and Be, B co-doping : a DFT study Type A1 Journal article
Year 2015 Publication RSC advances Abbreviated Journal Rsc Adv
Volume 5 Issue 5 Pages 55762-55773
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract First-principles density functional theory (DFT) calculations were carried out to investigate the structural and electronic properties of beryllium (Be) doped and Be and boron (B) co-doped graphene systems. We observed that not only the concentration of impurity atoms is important to tune the band-gap to some desired level, but also the specific substitution sites play a key role. In our system, which consists of 32 atoms, a maximum of 4Be and, in the co-doped state, 2Be and 3B atom substitutions are investigated. Both dopants are electron deficient relative to C atoms and cause the Fermi level to shift downward (p-type doping). A maximum band gap of 1.44 eV can be achieved on incorporation of 4Be atoms. The introduction of Be is more sensitive in terms of geometry and stability than B. However, in opening the energy gap, Be is more effective than B and N (nitrogen). Our results offer the possibility to modify the band-gap of graphene sufficiently for utilization in diverse electronic device applications.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000357803200018 Publication Date 2015-06-17
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 33 Open Access
Notes (down) ; ; Approved Most recent IF: 3.108; 2015 IF: 3.840
Call Number c:irua:127167 Serial 216
Permanent link to this record
 
 
Author Rønnow, T.F.; Pedersen, T.G.; Partoens, B.
Title Biexciton binding energy in fractional dimensional semiconductors Type A1 Journal article
Year 2012 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 85 Issue 4 Pages 045412-045412,7
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Biexcitons in fractional dimensional spaces are studied using variational quantum Monte Carlo. We investigate the biexciton binding energy as a function of the electron-hole mass fraction sigma as well as study the dimensional dependence of biexcitons for sigma = 0 and sigma = 1. As our first application of this model we treat the H(2) molecule in two and three dimensions. Next we investigate biexcitons in carbon nanotubes within the fractional dimensional model. To this end we find a relation between the nanotube radius and the effective dimension. The results of both applications are compared with results obtained using different models and we find a reasonable agreement. Within the fractional dimensional model we find that the biexciton binding energy in carbon nanotubes accurately scales as E(B)(r,epsilon) = 1280 meV angstrom/(r epsilon), as a function of radius r and the dielectric screening epsilon.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000298922200008 Publication Date 2012-01-06
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 21 Open Access
Notes (down) ; ; Approved Most recent IF: 3.836; 2012 IF: 3.767
Call Number UA @ lucian @ c:irua:96234 Serial 231
Permanent link to this record
 
 
Author Vinchurkar, S.; De Backer, L.; Vos, W.; Van Holsbeke, C.; de Backer, J.; de Backer, W.
Title A case series on lung deposition analysis of inhaled medication using functional imaging based computational fluid dynamics in asthmatic patients : effect of upper airway morphology and comparison with in vivo data Type A1 Journal article
Year 2012 Publication Inhalation Toxicology Abbreviated Journal Inhal Toxicol
Volume 24 Issue 2 Pages 81-88
Keywords A1 Journal article; Pharmacology. Therapy; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract Context: Asthma affects 20 million Americans resulting in an economic burden of approximately $18 billion in the US alone (Allergies and Asthma Foundation 2000; National Center for Environmental Health (NCEH) 1999). Research studies based on differences in patient-specific airway morphology for asthma and the associated effect on deposition of inhaled aerosols are currently not available in the literature. Therefore, the role of morphological variations such as upper airway (extrathoracic) occlusion is not well documented. Objective: Functional imaging based computational fluid dynamics (CFD) of the respiratory airways for five asthmatic subjects is performed in this study using computed tomography (CT) based patient-specific airway models and boundary conditions. Methods: CT scans for 5 asthma patients were used to reconstruct 3D lung models using segmentation software. An averaged inhalation profile and patient-specific lobar flow distribution were used to perform the simulation. The simulations were used to obtain deposition for BDP/Formoterol (R) HFA pMDI in the patient-specific airway models. Results: The lung deposition obtained using CFD was in excellent agreement with available in vivo data using the same product. Specifically, CFD resulted in 30% lung deposition, whereas in vivo lung deposition was reported to be approximately 31%. Conclusion: It was concluded that a combination of patient-specific airway models and lobar boundary conditions can be used to obtain accurate lung deposition estimates. Lower lung deposition can be expected for patients with higher extrathoracic resistance. Novel respiratory drug delivery devices need to accommodate population subgroups based on these morphological and anatomical differences in addition to subject age.
Address
Corporate Author Thesis
Publisher Place of Publication New York, N.Y. Editor
Language Wos 000299744800001 Publication Date 2012-01-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0895-8378;1091-7691; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.751 Times cited 36 Open Access
Notes (down) ; ; Approved Most recent IF: 1.751; 2012 IF: 1.894
Call Number UA @ lucian @ c:irua:96238 Serial 286
Permanent link to this record
 
 
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.
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 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 (down) ; ; Approved Most recent IF: 2.528; 2014 IF: 2.798
Call Number UA @ lucian @ c:irua:115759 Serial 308
Permanent link to this record
 
 
Author Austing, D.G.; Payette, C.; Yu, G.; Gupta, J.A.; Aers, G.C.; Nair, S.V.; Partoens, B.; Amaha, S.; Tarucha, S.
Title Characterization and modeling of single-particle energy levels and resonant currents in a coherent quantum dot mixer Type P1 Proceeding
Year 2011 Publication AIP conference proceedings T2 – 30th International Conference on the Physics of Semiconductors (ICPS-30), JUL 25-30, 2010, Seoul, SOUTH KOREA Abbreviated Journal
Volume Issue Pages 1-2
Keywords P1 Proceeding; Condensed Matter Theory (CMT)
Abstract We characterize and model the single-particle energy level position and resonant current strength at a three-level crossing in a coherent mixer composed of two weakly coupled vertical quantum dots. In addition to clear anticrossing behavior, an otherwise strong resonance is completely extinguished at the center of the crossing. Despite the strong variation in energy level position and resonant current strength throughout the crossing region, the resonance widths and the sum of the branch currents are found to be approximately constant.
Address
Corporate Author Thesis
Publisher Place of Publication New York Editor
Language Wos 000301053000453 Publication Date 2011-12-28
Series Editor Series Title Abbreviated Series Title
Series Volume 1399 Series Issue Edition
ISSN ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes (down) ; ; Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:113070 Serial 314
Permanent link to this record
 
 
Author Sels, D.; Brosens, F.; Magnus, W.
Title Classical trajectories : a powerful tool for solving tunneling problems Type A1 Journal article
Year 2012 Publication Physica: A : theoretical and statistical physics Abbreviated Journal Physica A
Volume 391 Issue 1/2 Pages 78-81
Keywords A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT)
Abstract In the realm of Ehrenfests theorem, classical trajectories obeying Newtons laws have been proven useful to construct explicit solutions to the time-dependent WignerLiouville equation. Whereas previous works have particularly focused on the initial distribution function as a vehicle found to carry the signatures of quantum statistics into the time-dependent solution, the present paper shows that the LagrangeCharpit method based on classical trajectories can be successfully invoked as well to tackle quantum mechanical features with no classical counterpart, such as tunneling.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000297230700010 Publication Date 2011-08-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0378-4371; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.243 Times cited 7 Open Access
Notes (down) ; ; Approved Most recent IF: 2.243; 2012 IF: 1.676
Call Number UA @ lucian @ c:irua:92359 Serial 370
Permanent link to this record
 
 
Author Van Duppen, B.; Peeters, F.M.
Title Comment on “Chiral tunneling in trilayer graphene” [Appl. Phys. Lett. 100, 163102 (2012)] Type Editorial
Year 2012 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 101 Issue 22 Pages 226101-1
Keywords Editorial; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Amer inst physics Place of Publication Melville Editor
Language Wos 000311967000107 Publication Date 2012-11-29
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 7 Open Access
Notes (down) ; ; Approved Most recent IF: 3.411; 2012 IF: 3.794
Call Number UA @ lucian @ c:irua:105999 Serial 408
Permanent link to this record
 
 
Author Pham, A.-T.; Zhao, Q.-T.; Jungemann, C.; Meinerzhagen, B.; Mantl, S.; Sorée, B.; Pourtois, G.
Title Comparison of strained SiGe heterostructure-on-insulator (0 0 1) and (1 1 0) PMOSFETs : CV characteristics, mobility, and ON current Type A1 Journal article
Year 2011 Publication Solid state electronics Abbreviated Journal Solid State Electron
Volume 65-66 Issue Pages 64-71
Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Strained SiGe heterostructure-on-insulator (0 0 1) and (1 1 0) PMOSFETs are investigated including important aspects like CV characteristics, mobility, and ON current. The simulations are based on the self-consistent solution of 6 × 6 k · p Schrödinger Equation, multi subband Boltzmann Transport Equation and Poisson Equation, and capture size quantization, strain, crystallographic orientation, and SiGe alloy effects on a solid physical basis. The simulation results are validated by comparison with different experimental data sources. The simulation results show that the strained SiGe HOI PMOSFET with (1 1 0) surface orientation has a higher gate capacitance and a much higher mobility and ON current compared to a similar device with the traditional (0 0 1) surface orientation.
Address
Corporate Author Thesis
Publisher Place of Publication Oxford Editor
Language Wos 000297182700012 Publication Date 2011-07-29
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0038-1101; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.58 Times cited 2 Open Access
Notes (down) ; ; Approved Most recent IF: 1.58; 2011 IF: 1.397
Call Number UA @ lucian @ c:irua:92866 Serial 433
Permanent link to this record
 
 
Author Khaydarov, R.T.; Beisinbaeva, H.B.; Sabitov, M.M.; Kalal, M.; Berdiyorov, G.R.
Title Conditions defining the mechanisms of the formation of light gas ions in multicomponent laser-produced plasmas Type A1 Journal article
Year 2010 Publication Nuclear fusion Abbreviated Journal Nucl Fusion
Volume 50 Issue 10 Pages 105007,1-105007,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using the mass-spectrometric method we study the charge, energy and spatial characteristics of ions in multicomponent plasma, generated under the action of Nd : YAG laser radiation on the surface of solid targets. We focus on the effect of the entry form of light gas atoms on the parameters of ions in such laser-produced plasmas. We found that the presence of light gas atoms considerably affects the parameters (e.g. the intensity and the charge multiplicity) of the heavier ions.
Address
Corporate Author Thesis
Publisher Place of Publication Vienna Editor
Language Wos 000281859300008 Publication Date 2010-08-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0029-5515;1741-4326; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.307 Times cited 1 Open Access
Notes (down) ; ; Approved Most recent IF: 3.307; 2010 IF: 3.303
Call Number UA @ lucian @ c:irua:84876 Serial 476
Permanent link to this record
 
 
Author Connolly, M.R.; Bemding, S.J.; Milošević, M.V.; Clem, J.R.; Tamegai, T.
Title Continuum versus discrete flux behaviour in large mesoscopic Bi2Sr2CaCu2O8+\delta disks Type A1 Journal article
Year 2010 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 470 Issue S:1 Pages S896-S897
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We have used scanning Hall probe and local Hall magnetometry measurements to map flux profiles in superconducting Bi2Sr2CaCu2O8+δ disks whose diameters span the crossover between the bulk and mesoscopic vortex regimes. The behaviour of large disks (greater-or-equal, slanted20 μm diameter) is well described by analytic models that assume a continuous distribution of flux in the sample. Small disks (less-than-or-equals, slant10 μm diameter), on the other hand, exhibit clear signatures of the underlying discrete vortex structure as well as competition between triangular Abrikosov ordering and the formation of shell structures driven by interactions with circulating edge currents. At low fields we are able to directly observe the characteristic mesoscopic compression of vortex clusters which is linked to oscillations in the diameter of the vortex dome in increasing magnetic fields. At higher fields, where single vortex resolution is lost, we are still able to track configurational changes in the vortex patterns, since competing vortex orders impose unmistakable signatures on local magnetisation curves. Our observations are in excellent agreement with molecular-dynamics numerical simulations which lead us to a natural definition of the lengthscale for the crossover between discrete and continuum behaviour in our system.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000286075700384 Publication Date 2009-11-20
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4534; ISBN Additional Links UA library record; WoS full record
Impact Factor 1.404 Times cited Open Access
Notes (down) ; ; Approved Most recent IF: 1.404; 2010 IF: 1.415
Call Number UA @ lucian @ c:irua:88069 Serial 494
Permanent link to this record
 
 
Author Grimaldi, G.; Leo, A.; Nigro, A.; Silhanek, A.V.; Verellen, N.; Moshchalkov, V.V.; Milošević, M.V.; Casaburi, A.; Cristiano, R.; Pace, S.
Title Controlling flux flow dissipation by changing flux pinning in superconducting films Type A1 Journal article
Year 2012 Publication Applied physics letters Abbreviated Journal Appl Phys Lett
Volume 100 Issue 20 Pages 202601-202601,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the flux flow state in superconducting materials characterized by rather strong intrinsic pinning, such as Nb, NbN, and nanostructured Al thin films, in which we drag the superconducting dissipative state into the normal state by current biasing. We modify the vortex pinning strength either by ion irradiation, by tuning the measuring temperature or by including artificial pinning centers. We measure critical flux flow voltages for all materials and the same effect is observed: switching to low flux flow dissipations at low fields for an intermediate pinning regime. This mechanism offers a way to additionally promote the stability of the superconducting state. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4718309]
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000304265000051 Publication Date 2012-05-14
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 33 Open Access
Notes (down) ; ; Approved Most recent IF: 3.411; 2012 IF: 3.794
Call Number UA @ lucian @ c:irua:98946 Serial 504
Permanent link to this record
 
 
Author Berdiyorov, G.R.; Milošević, M.V.; Peeters, F.M.
Title Dynamics of kinematic vortices in a mesoscopic superconducting loop Type A1 Journal article
Year 2010 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 470 Issue 19 Pages 946-948
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using the time-dependent GinzburgLandau formalism, we study the dynamic properties of a submicron superconducting loop in applied current and in presence of a perpendicular magnetic field. The resistive state of the sample is caused by the motion of kinematic vortexantivortex pairs. Vortices and antivortices move in opposite directions to each other, perpendicularly to the applied drive, and the periodic creation and annihilation of such pairs results in periodic oscillations of the voltage across the sample. The dynamics of these kinematic pairs is strongly influenced by the applied magnetic field, which for high fields leads to the flow of just vortices. Kinematic vortices can be temporarily pinned inside the loop with observable trace in the voltage vs. time characteristics.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000282454400061 Publication Date 2010-03-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4534; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.404 Times cited 9 Open Access
Notes (down) ; ; Approved Most recent IF: 1.404; 2010 IF: 1.415
Call Number UA @ lucian @ c:irua:85039 Serial 777
Permanent link to this record
 
 
Author Khaydarov, R.T.; Beisinbaeva, H.B.; Sabitov, M.M.; Kalal, M.; Berdiyorov, G.R.
Title Effect of light gas atom inclusions on the characteristics of laser-produced plasma ions Type A1 Journal article
Year 2011 Publication Nuclear fusion Abbreviated Journal Nucl Fusion
Volume 51 Issue 10 Pages 103041,1-103041,3
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using the mass-spectrometric method we studied the effect of light gas inclusions on the formation process of multi-component laser-induced plasma ions. Masscharge characteristics, as well as energy and spatial distribution of the plasma ions are analysed. We found that both the energy and maximal charge of heavy component ions decrease due to the presence of gas atoms in the solid target surface layer.
Address
Corporate Author Thesis
Publisher Place of Publication Vienna Editor
Language Wos 000296603800043 Publication Date 2011-09-23
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0029-5515;1741-4326; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.307 Times cited 1 Open Access
Notes (down) ; ; Approved Most recent IF: 3.307; 2011 IF: 4.090
Call Number UA @ lucian @ c:irua:93761 Serial 821
Permanent link to this record
 
 
Author de Backer, W.; Vos, W.; Van Holsbeke, C.; Vinchurkar, S.; Claes, R.; Hufkens, A.; Parizel, P.M.; Bedert, L.; de Backer, J.
Title The effect of roflumilast in addition to LABA/LAMA/ICS treatment in COPD patients Type L1 Letter to the editor
Year 2014 Publication European Respiratory Journal Abbreviated Journal Eur Respir J
Volume 44 Issue 2 Pages 527-529
Keywords L1 Letter to the editor; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Copenhagen Editor
Language Wos 000340017300029 Publication Date 2014-05-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0903-1936;1399-3003; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 10.569 Times cited 26 Open Access
Notes (down) ; ; Approved Most recent IF: 10.569; 2014 IF: 7.636
Call Number UA @ lucian @ c:irua:117335 Serial 832
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Author De Backer, L.; Vos, W.; Dieriks, B.; Daems, D.; Verhulst, S.; Vinchurkar, S.; Ides, K.; de Backer, J.; Germonpré, P.; de Backer, W.
Title The effects of long-term noninvasive ventilation in hypercapnic COPD patients : a randomized controlled pilot study Type A1 Journal article
Year 2011 Publication International journal of chronic obstructive pulmonary disease Abbreviated Journal Int J Chronic Obstr
Volume 6 Issue Pages 615-624
Keywords A1 Journal article; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract Introduction: Noninvasive ventilation (NIV) is a well-established treatment for acute-on-chronic respiratory failure in hypercapnic COPD patients. Less is known about the effects of a long-term treatment with NIV in hypercapnic COPD patients and about the factors that may predict response in terms of improved oxygenation and lowered CO2 retention.Methods: In this study, we randomized 15 patients to a routine pharmacological treatment (n = 5, age 66 [standard deviation ± 6] years, FEV1 30.5 [±5.1] %pred, PaO2 65 [±6] mmHg, PaCO2 52.4 [±6.0] mmHg) or to a routine treatment and NIV (using the Synchrony BiPAP device [Respironics, Inc, Murrsville, PA]) (n = 10, age 65 [±7] years, FEV1 29.5 [±9.0] %pred, PaO2 59 [±13] mmHg, PaCO2 55.4 [±7.7] mmHg) for 6 months. We looked at arterial blood gasses, lung function parameters and performed a low-dose computed tomography of the thorax, which was later used for segmentation (providing lobe and airway volumes, iVlobe and iVaw) and post-processing with computer methods (providing airway resistance, iRaw) giving overall a functional image of the separate airways and lobes.Results: In both groups there was a nonsignificant change in FEV1 (NIV group 29.5 [9.0] to 38.5 [14.6] %pred, control group 30.5 [5.1] to 36.8 [8.7] mmHg). PaCO2 dropped significantly only in the NIV group (NIV: 55.4 [7.7] → 44.5 [4.70], P = 0.0076; control: 52.4 [6.0] → 47.6 [8.2], NS). Patients actively treated with NIV developed a more inhomogeneous redistribution of mass flow than control patients. Subsequent analysis indicated that in NIV-treated patients that improve their blood gases, mass flow was also redistributed towards areas with higher vessel density and less emphysema, indicating that flow was redistributed towards areas with better perfusion. There was a highly significant correlation between the % increase in mass flow towards lobes with a blood vessel density of >9% and the increase in PaO2. Improved ventilation–perfusion match and recruitment of previously occluded small airways can explain the improvement in blood gases.Conclusion: We can conclude that in hypercapnic COPD patients treated with long-term NIV over 6 months, a mass flow redistribution occurs, providing a better ventilation–perfusion match and hence better blood gases and lung function. Control patients improve homogeneously in iVaw and iRaw, without improvement in gas exchange since there is no improved ventilation/perfusion ratio or increased alveolar ventilation. These differences in response can be detected through functional imaging, which gives a more detailed report on regional lung volumes and resistances than classical lung function tests do. Possibly only patients with localized small airway disease are good candidates for long-term NIV treatment. To confirm this and to see if better arterial blood gases also lead to better health related quality of life and longer survival, we have to study a larger population.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000208709800066 Publication Date 2011-11-18
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 28 Open Access
Notes (down) ; ; Approved Most recent IF: 3.157; 2011 IF: NA
Call Number UA @ lucian @ c:irua:93164 Serial 866
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Author Dixit, H.; Tandon, N.; Cottenier, S.; Saniz, R.; Lamoen, D.; Partoens, B.
Title Erratum : First-principles study of possible shallow donors in ZnAl2O4 spinel [Phys. Rev. B 87, 174101 (2013)] Type A1 Journal article
Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 88 Issue 5 Pages 059905-2
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000323572600009 Publication Date 2013-08-27
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 1 Open Access
Notes (down) ; ; Approved Most recent IF: 3.836; 2013 IF: 3.664
Call Number UA @ lucian @ c:irua:110015 Serial 1080
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Author Saniz, R.; Barbiellini, B.; Denison, A.B.; Bansil, A.
Title Erratum: Spontaneous magnetization and electron momentum density in three-dimensional quantum dots [Phys. Rev. B 68, 165326 (2003)] Type A1 Journal article
Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 84 Issue 11 Pages 119907
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000295263600015 Publication Date 2011-09-28
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
Impact Factor 3.836 Times cited Open Access
Notes (down) ; ; Approved Most recent IF: 3.836; 2011 IF: 3.691
Call Number UA @ lucian @ c:irua:92919 Serial 1081
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Author Silhanek, A.V.; Kramer, R.G.B.; van de Vondel, J.; Moshchalkov, V.V.; Milošević, M.V.; Berdiyorov, G.R.; Peeters, F.M.; Luccas, R.F.; Puig, T.
Title Freezing vortex rivers Type A1 Journal article
Year 2010 Publication Physica: C : superconductivity Abbreviated Journal Physica C
Volume 470 Issue 19 Pages 726-729
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We demonstrate experimentally and theoretically that the dissipative state at high current densities of superconducting samples with a periodic array of holes consist of flux rivers resulting from a short range attractive interaction between vortices. This dynamically induced vortexvortex attraction results from the migration of quasiparticles out of the vortex core. We have directly visualized the formation of vortex chains by scanning Hall microscopy after freezing the dynamic state by a field cooling procedure at constant bias current. Similar experiments carried out in a sample without holes show no hint of flux river formation.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000282454400004 Publication Date 2010-03-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0921-4534; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.404 Times cited 4 Open Access
Notes (down) ; ; Approved Most recent IF: 1.404; 2010 IF: 1.415
Call Number UA @ lucian @ c:irua:85032 Serial 1278
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Author De Backer, L.A.; Vos, W.G.; Salgado, R.; de Backer, J.W.; Devolder, A.; Verhulst, S.L.; Claes, R.; Germonpré, P.R.; de Backer, W.A.
Title Functional imaging using computer methods to compare the effect of salbutamol and ipratropium bromide in patient-specific airway models of COPD Type A1 Journal article
Year 2011 Publication International journal of chronic obstructive pulmonary disease Abbreviated Journal Int J Chronic Obstr
Volume 6 Issue Pages 637-646
Keywords A1 Journal article; Condensed Matter Theory (CMT); Vision lab; Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract Background: Salbutamol and ipratropium bromide improve lung function in patients with chronic obstructive pulmonary disease (COPD). However, their bronchodilating effect has not yet been compared in the central and distal airways. Functional imaging using computational fluid dynamics offers the possibility of making such a comparison. The objective of this study was to assess the effects of salbutamol and ipratropium bromide on the geometry and computational fluid dynamics-based resistance of the central and distal airways.Methods: Five patients with Global Initiative for Chronic Obstructive Lung Disease Stage III COPD were randomized to a single dose of salbutamol or ipratropium bromide in a crossover manner with a 1-week interval between treatments. Patients underwent lung function testing and a multislice computed tomography scan of the thorax that was used for functional imaging. Two hours after dosing, the patients again underwent lung function tests and repeat computed tomography.Results: Lung function parameters, including forced expiratory volume in 1 second, vital capacity, overall airway resistance, and specific airway resistance, changed significantly after administration of each product. On functional imaging, the bronchodilating effect was greater in the distal airways, with a corresponding drop in airway resistance, compared with the central airways. Salbutamol and ipratropium bromide were equally effective at first glance when looking at lung function tests, but when viewed in more detail with functional imaging, hyporesponsiveness could be shown for salbutamol in one patient. Salbutamol was more effective in the other patients.Conclusion: This pilot study gives an innovative insight into the modes of action of salbutamol and ipratropium bromide in patients with COPD, using the new techniques of functional imaging and computational fluid dynamics.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000208709800068 Publication Date 2011-11-28
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 25 Open Access
Notes (down) ; ; Approved Most recent IF: 3.157; 2011 IF: NA
Call Number UA @ lucian @ c:irua:93165 Serial 1300
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Author Van Holsbeke, C.; Vos, W.; van Hoorenbeeck, K.; Boudewyns, A.; Salgado, R.; Verdonck, P.R.; Ramet, J.; de Backer, J.; De Backer, W.; Verhulst, S.L.
Title Functional respiratory imaging as a tool to assess upper airway patency in children with obstructive sleep apnea Type A1 Journal article
Year 2013 Publication Sleep Medicine Abbreviated Journal Sleep Med
Volume 14 Issue 5 Pages 433-439
Keywords A1 Journal article; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract Objective: We aim to investigate if anatomical and functional properties of the upper airway using computerized 3D models derived from computed tomography (CT) scans better predict obstructive sleep apnea (OSA) severity than standard clinical markers. Methods: Consecutive children with suspected OSA underwent polysomnography, clinical assessment of upper airway patency, and a CT scan while awake. A three-dimensional (3D) reconstruction of the pharyngeal airway was built from these images, and computational fluid dynamics modeling of low inspiratory flow was performed using open-source software. Results: Thirty-three children were included (23 boys; mean age, was 6.0 +/- 3.2 y). OSA was diagnosed in 23 patients. Children with OSA had a significantly lower volume of the overlap region between tonsils and the adenoids (median volume, 1408 mm compared to 2173 mm; p = 0.04), a lower mean cross-sectional area at this location (median volume, 69.3 mm(2) compared to 114.3 mm(2); p = 0.04), and a lower minimal cross-sectional area (median volume, 17.9 mm(2) compared to 25.9 mm(2); p = 0.05). Various significant correlations were found between several imaging parameters and the severity of OSA, most pronounced for upper airway conductance (r = -0.46) (p < 0.01) for correlation between upper airway conductance and the apnea-hypopnea index. No differences or significant correlations were observed with clinical parameters of upper airway patency. Preliminary data after treatment showed that none of the patients with residual OSA had their smallest cross-sectional area located in segment 3, and this frequency was significantly lower than in their peers whose sleep study normalized (64%; p = 0.05). Conclusion: Functional imaging parameters are highly correlated with OSA severity and are a more powerful correlate than clinical scores of upper airway patency. Preliminary data also showed that we could identify differences in the upper airway of those subjects who did not benefit from a local upper airway treatment. (c) 2013 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Amsterdam Editor
Language Wos 000318612100009 Publication Date 2013-03-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1389-9457; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.391 Times cited 18 Open Access
Notes (down) ; ; Approved Most recent IF: 3.391; 2013 IF: 3.100
Call Number UA @ lucian @ c:irua:109015 Serial 1302
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Author Van Holsbeke, C.S.; Leemans, G.; Vos, W.G.; de Backer, J.W.; Vinchurkar, S.C.; Geldof, M.; Verdonck, P.R.; Parizel, P.M.; van Schil, P.E.; de Backer, W.A.
Title Functional Respiratory Imaging as a tool to personalize respiratory treatment in subjects with unilateral diaphragmatic paralysis Type A1 Journal article
Year 2013 Publication Respiratory care Abbreviated Journal Resp Care
Volume Issue Pages 1-20
Keywords A1 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP)
Abstract In two subjects with a unilateral diaphragmatic paralysis and complaints of dyspnea, a completely different treatment approach was chosen despite similar anatomical and physiological abnormalities. These decisions were supported by the results generated by Functional Respiratory Imaging (FRI). FRI was able to generate functional information with respect to lobar ventilation and local drug deposition. In one subject, it was found that some lobes were poorly ventilated and drug deposition simulation showed that some regions were undertreated. This subject underwent a diaphragm plication to restore the ventilation. In the other subject, it was found that all lobes were still ventilated. A conservative approach with regular follow-up was chosen to wait for spontaneous recovery of the diaphragmatic function. Both subjects improved subjectively and objectively. These cases demonstrate how novel medical imaging techniques such as FRI can be used to personalize respiratory treatment in subjects with unilateral diaphragmatic paralysis.
Address
Corporate Author Thesis
Publisher Place of Publication Dallas, Tex. Editor
Language Wos 000349200100024 Publication Date 2013-12-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-1324;1943-3654; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.733 Times cited 5 Open Access
Notes (down) ; ; Approved Most recent IF: 1.733; 2013 IF: 1.840
Call Number UA @ lucian @ c:irua:112982 Serial 1303
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Author Brammertz, G.; Oueslati, S.; Buffiere, M.; Bekaert, J.; El Anzeery, H.; Messaoud, K.B.; Sahayaraj, S.; Nuytten, T.; Koble, C.; Meuris, M.; Poortmans, J.;
Title Investigation of properties limiting efficiency in Cu2ZnSnSe4-based solar cells Type A1 Journal article
Year 2015 Publication IEEE journal of photovoltaics Abbreviated Journal Ieee J Photovolt
Volume 5 Issue 5 Pages 649-655
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We have investigated different nonidealities in Cu2ZnSnSe4CdSZnO solar cells with 9.7% conversion efficiency, in order to determine what is limiting the efficiency of these devices. Several nonidealities could be observed. A barrier of about 300 meV is present for electron flow at the absorberbuffer heterojunction leading to a strong crossover behavior between dark and illuminated currentvoltage curves. In addition, a barrier of about 130 meV is present at the Moabsorber contact, which could be reduced to 15 meV by inclusion of a TiN interlayer. Admittance spectroscopy results on the devices with the TiN backside contact show a defect level with an activation energy of 170 meV. Using all parameters extracted by the different characterization methods for simulations of the two-diode model including injection and recombination currents, we come to the conclusion that our devices are limited by the large recombination current in the depletion region. Potential fluctuations are present in the devices as well, but they do not seem to have a special degrading effect on the devices, besides a probable reduction in minority carrier lifetime through enhanced recombination through the band tail defects.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000353524800026 Publication Date 2014-12-19
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2156-3381;2156-3403; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.712 Times cited 13 Open Access
Notes (down) ; ; Approved Most recent IF: 3.712; 2015 IF: 3.165
Call Number c:irua:123717 Serial 1734
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Author Cantoro, M.; Klekachev, A.V.; Nourbakhsh, A.; Sorée, B.; Heyns, M.M.; de Gendt, S.
Title Long-wavelength, confined optical phonons in InAs nanowires probed by Raman spectroscopy Type A1 Journal article
Year 2011 Publication European physical journal : B : condensed matter and complex systems Abbreviated Journal Eur Phys J B
Volume 79 Issue 4 Pages 423-428
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Strongly confined nano-systems, such as one-dimensional nanowires, feature deviations in their structural, electronic and optical properties from the corresponding bulk. In this work, we investigate the behavior of long-wavelength, optical phonons in vertical arrays of InAs nanowires by Raman spectroscopy. We attribute the main changes in the spectral features to thermal anharmonicity, due to temperature effects, and rule out the contribution of quantum confinement and Fano resonances. We also observe the appearance of surface optical modes, whose details allow for a quantitative, independent estimation of the nanowire diameter. The results shed light onto the mechanisms of lineshape change in low-dimensional InAs nanostructures, and are useful to help tailoring their electronic and vibrational properties for novel functionalities.
Address
Corporate Author Thesis
Publisher Place of Publication Berlin Editor
Language Wos 000288120600005 Publication Date 2011-02-03
Series Editor Series Title Abbreviated Series Title
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 10 Open Access
Notes (down) ; ; Approved Most recent IF: 1.461; 2011 IF: 1.534
Call Number UA @ lucian @ c:irua:89502 Serial 1841
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Author Papp, G.; Peeters, F.M.
Title Magnetoresistance in a hybrid ferromagnetic/semiconductor device Type A1 Journal article
Year 2010 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 107 Issue 6 Pages 063718,1-063718,4
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Ballistic transport of a two-dimensional electron gas (2DEG) in a rectangle shaped wire, subjected to a local nonhomogeneous magnetic field that results from an in-plane magnetized ferromagnetic (FM) strip deposited above the 2DEG, is investigated theoretically. We found a positive magnetoresistance (MR), which exhibits hysteresis behavior with respect to the direction of the magnetic field sweep, in agreement with a recent experiment. This positive MR can be tuned by applying a gate voltage to the FM strip.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000276210800063 Publication Date 2010-04-01
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 2.068 Times cited 10 Open Access
Notes (down) ; ; Approved Most recent IF: 2.068; 2010 IF: 2.079
Call Number UA @ lucian @ c:irua:82281 Serial 1927
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Author Çakir, D.; Otalvaro, D.M.; Brocks, G.
Title Magnetoresistance in multilayer fullerene spin valves: A first-principles study Type A1 Journal article
Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 90 Issue 24 Pages 245404
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Carbon-based molecular semiconductors are explored for application in spintronics because their small spinorbit coupling promises long spin lifetimes. We calculate the electronic transport from first principles through spin valves comprising bi-and tri-layers of the fullerene molecules C-60 and C-70, sandwiched between two Fe electrodes. The spin polarization of the current, and the magnetoresistance depend sensitively on the interactions at the interfaces between the molecules and the metal surfaces. They are much less affected by the thickness of the molecular layers. A high current polarization (CP > 90%) and magnetoresistance (MR > 100%) at small bias can be attained using C-70 layers. In contrast, the current polarization and the magnetoresistance at small bias are vanishingly small for C-60 layers. Exploiting a generalized Julliere model we can trace the differences in spin-dependent transport between C-60 and C-70 layers to differences between the molecule-metal interface states. These states also allow one to interpret the current polarization and the magnetoresistance as a function of the applied bias voltage.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000345875200005 Publication Date 2014-12-02
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 13 Open Access
Notes (down) ; ; Approved Most recent IF: 3.836; 2014 IF: 3.736
Call Number UA @ lucian @ c:irua:122177 Serial 1928
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