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Author Becker, T.; Nelissen, K.; Cleuren, B.; Partoens, B.; Van den Broeck, C. url  doi
openurl 
  Title Comment on “Generalized exclusion processes : transport coefficients” Type A1 Journal article
  Year 2016 Publication Physical review E Abbreviated Journal Phys Rev E  
  Volume 93 Issue 93 Pages 046101  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) In a recent paper, Arita et al. [Phys. Rev. E 90, 052108 (2014)] consider the transport properties of a class of generalized exclusion processes. Analytical expressions for the transport-diffusion coefficient are derived by ignoring correlations. It is claimed that these expressions become exact in the hydrodynamic limit. In this Comment,we point out that (i) the influence of correlations upon the diffusion does not vanish in the hydrodynamic limit, and (ii) the expressions for the self- and transport diffusion derived by Arita et al. are special cases of results derived in Becker et al. [Phys. Rev. Lett. 111, 110601 (2013)].  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000374962100019 Publication Date 2016-04-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0045;2470-0053; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.366 Times cited 3 Open Access  
  Notes Approved Most recent IF: 2.366  
  Call Number UA @ lucian @ c:irua:141060 Serial 4591  
Permanent link to this record
 

 
Author Reijniers, J.; Partoens, B.; Steckel, J.; Peremans, H. doi  openurl
  Title HRTF measurement by means of unsupervised head movements with respect to a single fixed speaker Type A1 Journal article
  Year 2020 Publication Ieee Access Abbreviated Journal Ieee Access  
  Volume 8 Issue Pages 92287-92300  
  Keywords A1 Journal article; Mass communications; Engineering Management (ENM); Condensed Matter Theory (CMT); Co-Design of Cyber-Physical Systems (Cosys-Lab)  
  Abstract (up) In a standard state-of-the-art measurement the head-related transfer function (HRTF) is obtained in an anechoic room with an elaborate setup involving multiple calibrated loudspeakers. In search for a simplified method that would open up the possibility for an HRTF measurement in a home environment, it has been suggested that this setup could be replaced with one with a single, fixed loudspeaker. In such a setup, the subject samples different directions by moving the head with respect to this loudspeaker, while the head movements are tracked in some way. In this paper, the feasibility of such an approach is studied. To this end, the HRTF is measured in an unmodified (non-anechoic) room by means of a single external speaker and a high resolution head tracking system. The differences between the dynamically obtained HRTF and the standard static HRTF are investigated, and are shown to be mostly due to variable torso reflections.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000539041600001 Publication Date 2020-05-15  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2169-3536 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.9 Times cited 4 Open Access  
  Notes ; This work was supported in part by the Research Foundation Flanders (FWO) under Grant G023619N, and in part by the Agency for Innovation and Entrepreneurship (VLAIO). ; Approved Most recent IF: 3.9; 2020 IF: 3.244  
  Call Number UA @ admin @ c:irua:170318 Serial 6539  
Permanent link to this record
 

 
Author Govaerts, K.; Sluiter, M.H.F.; Partoens, B.; Lamoen, D. url  doi
openurl 
  Title Homologous series of layered structures in binary and ternary Bi-Sb-Te-Se systems : ab initio study Type A1 Journal article
  Year 2014 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 89 Issue 5 Pages 054106-54109  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract (up) In order to account explicitly for the existence of long-periodic layered structures and the strong structural relaxations in the most common binary and ternary alloys of the Bi-Sb-Te-Se system, we have developed a one-dimensional cluster expansion (CE) based on first-principles electronic structure calculations, which accounts for the Bi and Sb bilayer formation. Excellent interlayer distances are obtained with a van der Waals density functional. It is shown that a CE solely based on pair interactions is sufficient to provide an accurate description of the ground-state energies of Bi-Sb-Te-Se binary and ternary systems without making the data set of ab initio calculated structures unreasonably large. For the binary alloys A1−xQx (A=Sb, Bi; Q=Te, Se), a ternary CE yields an almost continuous series of (meta)stable structures consisting of consecutive A bilayers next to consecutive A2Q3 for 0<x<0.6. For x>0.6, the binary alloy segregates into pure Q and A2Q3. The Bi-Sb system is described by a quaternary CE and is found to be an ideal solid solution stabilized by entropic effects at T≠0 K but with an ordered structure of alternating Bi and Sb layers for x=0.5 at T=0 K. A quintuple CE is used for the ternary Bi-Sb-Te system, where stable ternary layered compounds with an arbitrary stacking of Sb2Te3, Bi2Te3, and Te-Bi-Te-Sb-Te quintuple units are found, optionally separated by mixed Bi/Sb bilayers. Electronic properties of the stable compounds were studied taking spin-orbit coupling into account.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000332420900001 Publication Date 2014-03-05  
  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 5 Open Access  
  Notes Fwo; Hercules Approved Most recent IF: 3.836; 2014 IF: 3.736  
  Call Number UA @ lucian @ c:irua:114910 Serial 1487  
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Author Nikolaev, A.V.; Lamoen, D.; Partoens, B. pdf  url
doi  openurl
  Title Extension of the basis set of linearized augmented plane wave (LAPW) method by using supplemented tight binding basis functions Type A1 Journal article
  Year 2016 Publication The journal of chemical physics Abbreviated Journal J Chem Phys  
  Volume 145 Issue 145 Pages 014101  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract (up) In order to increase the accuracy of the linearized augmented plane wave (LAPW) method, we present a new approach where the plane wave basis function is augmented by two different atomic radial components constructed at two different linearization energies corresponding to two different electron bands (or energy windows). We demonstrate that this case can be reduced to the standard treatment within the LAPW paradigm where the usual basis set is enriched by the basis functions of the tight binding type, which go to zero with zero derivative at the sphere boundary. We show that the task is closely related with the problem of extended core states which is currently solved by applying the LAPW method with local orbitals (LAPW+LO). In comparison with LAPW+LO, the number of supplemented basis functions in our approach is doubled, which opens up a new channel for the extension of the LAPW and LAPW+LO basis sets. The appearance of new supplemented basis functions absent in the LAPW+LO treatment is closely related with the existence of the ul-component in the canonical LAPW method. We discuss properties of additional tight binding basis functions and apply the extended basis set for computation of electron energy bands of lanthanum (face and body centered structures) and hexagonal close packed lattice of cadmium. We demonstrate that the new treatment gives lower total energies in comparison with both canonical LAPW and LAPW+LO, with the energy difference more pronounced for intermediate and poor LAPW basis sets.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000379584700003 Publication Date 2016-07-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-9606 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.965 Times cited 11 Open Access  
  Notes A.V.N. acknowledges useful discussions with B. Verberck, E. V. Tkalya, and A. V. Bibikov. Approved Most recent IF: 2.965  
  Call Number c:irua:134290 Serial 4099  
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Author Rønnow, T.F.; Pedersen, T.G.; Partoens, B.; Berthelsen, K.K. url  doi
openurl 
  Title Variational quantum Monte Carlo study of charged excitons in fractional dimensional space Type A1 Journal article
  Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 84 Issue 3 Pages 035316-035316,13  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) In this article we study excitons and trions in fractional dimensional spaces using the model suggested by C. Palmer [ J. Phys. A: Math. Gen. 37 6987 (2004)] through variational quantum Monte Carlo. We present a direct approach for estimating the exciton binding energy and discuss the von Neumann rejection- and Metropolis sampling methods. A simple variational estimate of trions is presented which shows good agreement with previous calculations done within the fractional dimensional model presented by D. R. Herrick and F. H. Stillinger [ Phys. Rev. A 11 42 (1975) and J. Math. Phys. 18 1224 (1977)]. We explain the spatial physics of the positive and negative trions by investigating angular and inter-atomic distances. We then examine the wave function and explain the differences between the positive and negative trions with heavy holes. As applications of the fractional dimensional model we study three systems: First we apply the model to estimate the energy of the hydrogen molecular ion H2+. Then we estimate trion binding energies in GaAs-based quantum wells and we demonstrate a good agreement with other theoretical work as well as experimentally observed binding energies. Finally, we apply the results to carbon nanotubes. We find good agreement with recently observed binding energies of the positively charged trion.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000293129200012 Publication Date 2011-07-26  
  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 15 Open Access  
  Notes ; ; Approved Most recent IF: 3.836; 2011 IF: 3.691  
  Call Number UA @ lucian @ c:irua:91741 Serial 3837  
Permanent link to this record
 

 
Author Szumniak, P.; Bednarek, S.; Pawlowski, J.; Partoens, B. url  doi
openurl 
  Title All-electrical control of quantum gates for single heavy-hole spin qubits Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 87 Issue 19 Pages 195307-195312  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) In this paper several nanodevices which realize basic single heavy-hole qubit operations are proposed and supported by time-dependent self-consistent Poisson-Schrodinger calculations using a four band heavy-hole-light-hole model. In particular we propose a set of nanodevices which can act as Pauli X, Y, Z quantum gates and as a gate that acts similar to a Hadamard gate (i.e., it creates a balanced superposition of basis states but with an additional phase factor) on the heavy-hole spin qubit. We also present the design and simulation of a gated semiconductor nanodevice which can realize an arbitrary sequence of all these proposed single quantum logic gates. The proposed devices exploit the self-focusing effect of the hole wave function which allows for guiding the hole along a given path in the form of a stable solitonlike wave packet. Thanks to the presence of the Dresselhaus spin-orbit coupling, the motion of the hole along a certain direction is equivalent to the application of an effective magnetic field which induces in turn a coherent rotation of the heavy-hole spin. The hole motion and consequently the quantum logic operation is initialized only by weak static voltages applied to the electrodes which cover the nanodevice. The proposed gates allow for an all electric and ultrafast (tens of picoseconds) heavy-hole spin manipulation and give the possibility to implement a scalable architecture of heavy-hole spin qubits for quantum computation applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000319252200003 Publication Date 2013-05-21  
  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 14 Open Access  
  Notes ; This work was supported by the Polish National Science Center (Grant No. DEC-2011/03/N/ST3/02963), as well as by the “Krakow Interdisciplinary PhD-Project in Nanoscience and Advanced Nanostructures” operated within the Foundation for Polish Science MPD Programme, co-financed by the European Regional Development Fund. This research was supported in part by PL-Grid Infrastructure. ; Approved Most recent IF: 3.836; 2013 IF: 3.664  
  Call Number UA @ lucian @ c:irua:109002 Serial 88  
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Author Vansweevelt, R.; Mortet, V.; D' Haen, J.; Ruttens, bart; van Haesendonck, C.; Partoens, B.; Peeters, F.M.; Wagner, P. doi  openurl
  Title Study on the giant positive magnetoresistance and Hall effect in ultrathin graphite flakes Type A1 Journal article
  Year 2011 Publication Physica status solidi : A : applications and materials science Abbreviated Journal Phys Status Solidi A  
  Volume 208 Issue 6 Pages 1252-1258  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) In this paper, we report on the electronic transport properties of mesoscopic, ultrathin graphite flakes with a thickness corresponding to a stack of 150 graphene layers. The graphite flakes show an unexpectedly strong positive magnetoresistance (PMR) already at room temperature, which scales in good approximation with the square of the magnetic field. Furthermore, we show that the resistivity is unaffected by magnetic fields oriented in plane with the graphene layers. Hall effect measurements indicate that the charge carriers are p-type and their concentration increases with increasing temperature while the mobility is decreasing. The Hall voltage is non-linear in higher magnetic fields. Possible origins of the observed effects are discussed. Ball and stick model of the two topmost carbon layers of the hexagonal graphite structure.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000292945800008 Publication Date 2011-02-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1862-6300; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.775 Times cited 8 Open Access  
  Notes ; The authors gratefully acknowledge the support by FWO – Research Foundation Flanders (project G.0159.07 “Structural and electronic properties of biologically modified, graphene-based layers”), by the Federal Belgian Interuniversity Attraction Poles Programme BELSPO (project TAP VI P6/42 “Quantum effects in clusters and nanowires”) and by the Methusalem network “NANO – Antwerp-Hasselt,” funded by the Flemish Community. Technical assistance by Stoffel D. Janssens (magnet calibration and software development), Dr. Hong Yin (AFM-based thickness studies), Dr. Ronald Thoelen (data analysis), and Prof. Hans-Gerd Boyen (XPS spectroscopy) is greatly appreciated. ; Approved Most recent IF: 1.775; 2011 IF: 1.463  
  Call Number UA @ lucian @ c:irua:91941 Serial 3343  
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Author Govaerts, K.; Saniz, R.; Partoens, B.; Lamoen, D. url  doi
openurl 
  Title van der Waals bonding and the quasiparticle band structure of SnO from first principles Type A1 Journal article
  Year 2013 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 87 Issue 23 Pages 235210-235217  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract (up) In this work we have investigated the structural and electronic properties of SnO, which is built up from layers kept together by van der Waals (vdW) forces. The combination of a vdW functional within density functional theory (DFT) and quasiparticle band structure calculations within the GW approximation provides accurate values for the lattice parameters, atomic positions, and the electronic band structure including the fundamental (indirect) and the optical (direct) band gap without the need of experimental or empirical input. A systematic comparison is made between different levels of self-consistency within the GW approach {following the scheme of Shishkin et al. [Phys. Rev. B 75, 235102 (2007)]} and the results are compared with DFT and hybrid functional results. Furthermore, the effect of the vdW-corrected functional as a starting point for the GW calculation of the band gap has been investigated. Finally, we studied the effect of the vdW functional on the electron charge density.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000321061000003 Publication Date 2013-07-01  
  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 50 Open Access  
  Notes IWT; FWO; Hercules Approved Most recent IF: 3.836; 2013 IF: 3.664  
  Call Number UA @ lucian @ c:irua:109596 Serial 3835  
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Author Partoens, B. doi  openurl
  Title Spinorbit interactions : hide and seek Type A1 Journal article
  Year 2014 Publication Nature physics Abbreviated Journal Nat Phys  
  Volume 10 Issue Pages 333-334  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) It is commonly believed that solids with spatial inversion symmetry do not display spinorbit effects. However, first-principles calculations now reveal unexpected spin structure for centrosymmetric crystals  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000335371200003 Publication Date 2014-04-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1745-2473; 1745-2481 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 22.806 Times cited 8 Open Access  
  Notes Approved Most recent IF: 22.806; 2014 IF: 20.147  
  Call Number UA @ lucian @ c:irua:141068 Serial 4608  
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Author Avetisyan, A.A.; Partoens, B.; Peeters, F.M. url  doi
openurl 
  Title Electric-field control of the band gap and Fermi energy in graphene multilayers by top and back gates Type A1 Journal article
  Year 2009 Publication Physical review : B : solid state Abbreviated Journal Phys Rev B  
  Volume 80 Issue 19 Pages 195401,1-195401,11  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) It is known that a perpendicular electric field applied to multilayers of graphene modifies the electronic structure near the K point and may induce an energy gap in the electronic spectrum which is tunable by the gate voltage. Here we consider a system of graphene multilayers in the presence of a positively charged top and a negatively charged back gate to control independently the density of electrons on the graphene layers and the Fermi energy of the system. The band structure of three- and four-layer graphene systems in the presence of the top and back gates is obtained using a tight-binding approach. A self-consistent Hartree approximation is used to calculate the induced charges on the different graphene layers. We predict that for opposite and equal charges on the top and bottom layers an energy gap is opened at the Fermi level. For an even number of layers this gap is larger than in the case of an odd number of graphene layers. We find that the circular asymmetry of the spectrum, which is a consequence of the trigonal warping, changes the size of the induced electronic gap, even when the total density of the induced electrons on the graphene layers is low.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000272311000087 Publication Date 2009-11-10  
  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 106 Open Access  
  Notes Approved Most recent IF: 3.836; 2009 IF: 3.475  
  Call Number UA @ lucian @ c:irua:80315 Serial 883  
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Author Reijniers, J.; Partoens, B.; Peremans, H. openurl 
  Title Noise-resistant correlation-based alignment of head-related transfer functions for high-fidelity spherical harmonics representation Type P3 Proceeding
  Year 2023 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords P3 Proceeding; Engineering sciences. Technology; Engineering Management (ENM); Condensed Matter Theory (CMT)  
  Abstract (up) It is standard practice in virtual reality applications to synthesize binaural audio based on a discrete set of directionally-dependent head-related impulse responses (HRIRs). This set of HRIRs is often time-aligned in a pre-processing step, to allow for high-fidelity interpolation between HRIRs corresponding with neighbouring directions. The fidelity of this operation depends on the similarity of neighbouring aligned HRIRs. The pairwise quality of similarity makes it a difficult criterion to optimize globally and consequently one often resorts to alignment methods based on a specific feature that can be extracted for each HRIR separately, e.g., the first-onset of the peak or the group delay. However, such proxies for similarity are very sensitive to noise and therefore require a high signal-to-noise ratio, which makes them less suitable for processing HRIRs acquired outside an anechoic room. In this paper, we advance a novel alignment method, which maximizes the similarity – defined as the correlation between the full-length HRIRs – between neighbouring aligned HRIRs for all directions at once. We show that this correlation-based alignment procedure outperforms the first-onset alignment with regards to the fidelity of the spherical harmonics representation of both the spectral and interaural time difference (ITD) information, when tested on the KEMAR HRIR and six human HRIRs. Finally, we show that the correlation-based alignment is more robust to noise.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos Publication Date  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:199714 Serial 9062  
Permanent link to this record
 

 
Author Leenaerts, O.; Vercauteren, S.; Partoens, B. url  doi
openurl 
  Title Band alignment of lateral two-dimensional heterostructures with a transverse dipole Type A1 Journal article
  Year 2017 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 110 Issue 110 Pages 181602  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) It was recently shown that the electronic band alignment in lateral two-dimensional heterostructures is strongly dependent on the system geometry, such as heterostructure width and layer thickness. This is so even in the absence of polar edge terminations because of the appearance of an interface dipole between the two different materials. In this study, this work is expanded to include two-dimensional materials that possess an electronic dipole over their surface, i.e., in the direction transverse to the crystal plane. To this end, a heterostucture consisting of polar hydrofluorinated graphene and non-polar graphane layers is studied with first-principles calculations. As for nonpolar heterostructures, a significant geometry dependence is observed with two different limits for the band offset. For infinitely wide heterostructures, the potential step in the vacuum is equally divided over the two sides of the heterostructure, resulting in a finite potential step in the heterostructure. For infinitely thick heterostructure slabs, on the other hand, the band offset is reduced, similar to the three-dimensional case.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000400931900014 Publication Date 2017-05-01  
  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 4 Open Access  
  Notes ; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-VI). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government-department EWI. ; Approved Most recent IF: 3.411  
  Call Number UA @ lucian @ c:irua:143755 Serial 4586  
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Author Paulus, A.; Hendrickx, M.; Mayda, S.; Batuk, M.; Reekmans, G.; von Holst, M.; Elen, K.; Abakumov, A.M.; Adriaensens, P.; Lamoen, D.; Partoens, B.; Hadermann, J.; Van Bael, M.K.; Hardy, A. pdf  url
doi  openurl
  Title Understanding the Activation of Anionic Redox Chemistry in Ti4+-Substituted Li2MnO3as a Cathode Material for Li-Ion Batteries Type A1 Journal article
  Year 2023 Publication ACS applied energy materials Abbreviated Journal ACS Appl. Energy Mater.  
  Volume 6 Issue 13 Pages 6956-6971  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract (up) Layered Li-rich oxides, demonstrating both cationic and anionic redox chemistry being used as positive electrodes for Li-ion batteries,have raised interest due to their high specific discharge capacities exceeding 250 mAh/g. However, irreversible structural transformations triggered by anionic redox chemistry result in pronounced voltagefade (i.e., lowering the specific energy by a gradual decay of discharge potential) upon extended galvanostatic cycling. Activating or suppressing oxygen anionic redox through structural stabilization induced by redox-inactivecation substitution is a well-known strategy. However, less emphasishas been put on the correlation between substitution degree and theactivation/suppression of the anionic redox. In this work, Ti4+-substituted Li2MnO3 was synthesizedvia a facile solution-gel method. Ti4+ is selected as adopant as it contains no partially filled d-orbitals. Our study revealedthat the layered “honeycomb-ordered” C2/m structure is preserved when increasing the Ticontent to x = 0.2 in the Li2Mn1-x Ti (x) O-3 solidsolution, as shown by electron diffraction and aberration-correctedscanning transmission electron microscopy. Galvanostatic cycling hintsat a delayed oxygen release, due to an improved reversibility of theanionic redox, during the first 10 charge-discharge cyclesfor the x = 0.2 composition compared to the parentmaterial (x = 0), followed by pronounced oxygen redoxactivity afterward. The latter originates from a low activation energybarrier toward O-O dimer formation and Mn migration in Li2Mn0.8Ti0.2O3, as deducedfrom first-principles molecular dynamics (MD) simulations for the“charged” state. Upon lowering the Ti substitution to x = 0.05, the structural stability was drastically improvedbased on our MD analysis, stressing the importance of carefully optimizingthe substitution degree to achieve the best electrochemical performance.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001018266700001 Publication Date 2023-07-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2574-0962 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.4 Times cited Open Access Not_Open_Access: Available from 24.12.2023  
  Notes Universiteit Hasselt, AUHL/15/2 – GOH3816N ; Russian Science Foundation, 20-43-01012 ; Fonds Wetenschappelijk Onderzoek, AUHL/15/2 – GOH3816N G040116N ; The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO Vlaanderen and the Flemish Government-department EWI. Approved Most recent IF: 6.4; 2023 IF: NA  
  Call Number EMAT @ emat @c:irua:198160 Serial 8809  
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Author Bercx, M.; Slap, L.; Partoens, B.; Lamoen, D. pdf  url
doi  openurl
  Title First-Principles Investigation of the Stability of the Oxygen Framework of Li-Rich Battery Cathodes Type A1 Journal article
  Year 2019 Publication MRS advances Abbreviated Journal MRS Adv.  
  Volume 4 Issue 14 Pages 813-820  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract (up) Lithium-rich layered oxides such as Li<sub>2</sub>MnO<sub>3</sub>have shown great potential as cathodes in Li-ion batteries, mainly because of their large capacities. However, these materials still suffer from structural degradation as the battery is cycled, reducing the average voltage and capacity of the cell. The voltage fade is believed to be related to the migration of transition metals into the lithium layer, linked to the formation of O-O dimers with a short bond length, which in turn is driven by the presence of oxygen holes due to the participation of oxygen in the redox process. We investigate the formation of O-O dimers for partially charged O1-Li<sub>2</sub>MnO<sub>3</sub>using a first-principles density functional theory approach by calculating the reaction energy and kinetic barriers for dimer formation. Next, we perform similar calculations for partially charged O1-Li<sub>2</sub>IrO<sub>3</sub>, a Li-rich material for which the voltage fade was not observed during cycling. When we compare the stability of the oxygen framework, we conclude that the formation of O-O dimers is both thermodynamically and kinetically viable for O1-Li<sub>0.5</sub>MnO<sub>3</sub>. For O1-Li<sub>0.5</sub>IrO<sub>3</sub>, we observe that the oxygen lattice is much more stable, either returning to its original state when perturbed, or resulting in a structure with an O-O dimer that is much higher in energy. This can be explained by the mixed redox process for Li<sub>2</sub>IrO<sub>3</sub>, which is also shown from the calculated magnetic moments. The lack of O-O dimer formation in O1-Li<sub>0.5</sub>IrO<sub>3</sub>provides valuable insight as to why Li<sub>2</sub>IrO<sub>3</sub>does not demonstrate a voltage fade as the battery is cycled, which can be used to design Li-rich battery cathodes with an improved cycling performance.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000466846700004 Publication Date 2019-02-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2059-8521 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 3 Open Access Not_Open_Access: Available from 22.02.2020  
  Notes We acknowledge the financial support of FWO-Vlaanderen through project G040116N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. Approved Most recent IF: NA  
  Call Number EMAT @ emat @UA @ admin @ c:irua:160121 Serial 5179  
Permanent link to this record
 

 
Author Schoeters, B.; Neyts, E.C.; Khalilov, U.; Pourtois, G.; Partoens, B. url  doi
openurl 
  Title Stability of Si epoxide defects in Si nanowires : a mixed reactive force field/DFT study Type A1 Journal article
  Year 2013 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 15 Issue 36 Pages 15091-15097  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract (up) Modeling the oxidation process of silicon nanowires through reactive force field based molecular dynamics simulations suggests that the formation of Si epoxide defects occurs both at the Si/SiOx interface and at the nanowire surface, whereas for flat surfaces, this defect is experimentally observed to occur only at the interface as a result of stress. In this paper, we argue that the increasing curvature stabilizes the defect at the nanowire surface, as suggested by our density functional theory calculations. The latter can have important consequences for the opto-electronic properties of thin silicon nanowires, since the epoxide induces an electronic state within the band gap. Removing the epoxide defect by hydrogenation is expected to be possible but becomes increasingly difficult with a reduction of the diameter of the nanowires.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge Editor  
  Language Wos 000323520600029 Publication Date 2013-07-16  
  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 3 Open Access  
  Notes ; BS gratefully acknowledges financial support of the IWT, Institute for the Promotion of Innovation by Science and Technology in Flanders, via the SBO project “SilaSol”. This work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish government and the Universiteit Antwerpen. ; Approved Most recent IF: 4.123; 2013 IF: 4.198  
  Call Number UA @ lucian @ c:irua:110793 Serial 3130  
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Author Leenaerts, O.; Partoens, B.; Peeters, F.M. doi  openurl
  Title Tunable double Dirac cone spectrum in bilayer \alpha-graphyne Type A1 Journal article
  Year 2013 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 103 Issue 1 Pages 013105-4  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) Monolayer alpha-graphyne was recently proposed as a new all-carbon material having an electronic spectrum consisting of Dirac cones. Based on a first-principles investigation of bilayer alpha-graphyne, we show that the electronic band structure is qualitatively different from its monolayer form and depends crucially on the stacking mode of the two layers. Two stable stacking modes are found: a configuration with a gapless parabolic band structure, similar to AB stacked bilayer graphene, and another one which exhibits a doubled Dirac-cone spectrum. The latter can be tuned by an electric field with a gap opening rate of 0.3 eA. (C) 2013 AIP Publishing LLC.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos 000321497200032 Publication Date 2013-07-01  
  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 58 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the NOI-BOF of the University of Antwerp, and the ESF EuroGRAPHENE project CONGRAN. ; Approved Most recent IF: 3.411; 2013 IF: 3.515  
  Call Number UA @ lucian @ c:irua:109821 Serial 3740  
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Author Leenaerts, O.; Partoens, B.; Peeters, F.M. pdf  url
doi  openurl
  Title Adsorption of H2O, NH3, CO, NO2, and NO on graphene: a first-principles study Type A1 Journal article
  Year 2008 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 77 Issue Pages 125416,1-6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) Motivated by the recent realization of graphene sensors to detect individual gas molecules, we investigate the adsorption of H2O, NH3, CO, NO2, and NO on a graphene substrate using first-principles calculations. The optimal adsorption position and orientation of these molecules on the graphene surface is determined and the adsorption energies are calculated. Molecular doping, i.e., charge transfer between the molecules and the graphene surface, is discussed in light of the density of states and the molecular orbitals of the adsorbates. The efficiency of doping of the different molecules is determined and the influence of their magnetic moment is discussed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000254543000133 Publication Date 2008-03-18  
  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 1392 Open Access  
  Notes This work was supported by the Flemish Science Foundation FWO-Vl, by the NOI-BOF of the University of Antwerp, and by the Belgian Science Policy IAP. Approved Most recent IF: 3.836; 2008 IF: 3.322  
  Call Number UA @ lucian @ c:irua:69634 Serial 67  
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Author Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B. pdf  url
doi  openurl
  Title The role of the VZn-NO-H complex in the p-type conductivity in ZnO Type A1 Journal article
  Year 2015 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 17 Issue 17 Pages 5485-5489  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract (up) Past research efforts aiming at obtaining stable p-type ZnO have been based on complexes involving nitrogen doping. A recent experiment by (J. G. Reynolds et al., Appl. Phys. Lett., 2013, 102, 152114) demonstrated a significant ([similar]1018 cm−3) p-type behavior in N-doped ZnO films after appropriate annealing. The p-type conductivity was attributed to a VZnNOH shallow acceptor complex, formed by a Zn vacancy (VZn), N substituting O (NO), and H interstitial (Hi). We present here a first-principles hybrid functional study of this complex compared to the one without hydrogen. Our results confirm that the VZnNOH complex acts as an acceptor in ZnO. We find that H plays an important role, because it lowers the formation energy of the complex with respect to VZnNO, a complex known to exhibit (unstable) p-type behavior. However, this additional H atom also occupies the hole level at the origin of the shallow behavior of VZnNO, leaving only two states empty higher in the band gap and making the VZnNOH complex a deep acceptor. Therefore, we conclude that the cause of the observed p-type conductivity in experiment is not the presence of the VZnNOH complex, but probably the formation of the VZnNO complex during the annealing process.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge Editor  
  Language Wos 000349616400080 Publication Date 2015-01-20  
  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 20 Open Access  
  Notes FWO G021614N; FWO G015013; FWO G018914N; GOA; Hercules Approved Most recent IF: 4.123; 2015 IF: 4.493  
  Call Number c:irua:123218 Serial 3592  
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Author Saniz, R.; Vercauteren, S.; Lamoen, D.; Partoens, B.; Barbiellini, B. pdf  doi
openurl 
  Title Accurate description of the van der Waals interaction of an electron-positron pair with the surface of a topological insulator Type P1 Proceeding
  Year 2014 Publication Journal of physics : conference series Abbreviated Journal  
  Volume 505 Issue Pages 012002  
  Keywords P1 Proceeding; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract (up) Positrons can be trapped in localized states at the surface of a material, and thus quite selectively interact with core or valence surface electrons. Hence, advanced surface positron spectroscopy techniques can present the ideal tools to study a topological insulator, where surface states play a fundamental role. We analyze the problem of a positron at a TI surface, assuming that it is a weakly physisorbed positronium (Ps) atom. To determine if the surface of interest in a material can sustain such a physisorption, an accurate description of the underlying van der Waals (vdW) interaction is essential. We have developed a first-principles parameterfree method, based on the density functional theory, to extract key parameters determining the vdW interaction potential between a Ps atom and the surface of a given material. The method has been successfully applied to quartz and preliminary results on Bi2Te2Se indicate the existence of a positron surface state. We discuss the robustness of our predictions versus the most relevant approximations involved in our approach.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos 000338216500002 Publication Date 2014-04-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1742-6588;1742-6596; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 2 Open Access  
  Notes ; We thank A. Weiss for very useful conversations. We acknowledge financial support from FWO-Vlaanderen (projectG.0150.13). This work was carried out using the HPC infrastructure of the University of Antwerp (CalcUA), adivision of the Flemish Supercomputer Center (VSC), funded by the Hercules foundation and the Flemish Government (EWI Department). B. B. is supported by DOE grants Nos. DE-FG02-07ER46352 and DE-AC02-05CH11231 for theory support at ALS, Berkeley, and a NERSC computer time allocation. ; Approved Most recent IF: NA  
  Call Number UA @ lucian @ c:irua:118264 Serial 46  
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Author Shi, W.; Callewaert, V.; Barbiellini, B.; Saniz, R.; Butterling, M.; Egger, W.; Dickmann, M.; Hugenschmidt, C.; Shakeri, B.; Meulenberg, R. W.; Brück, E.; Partoens, B.; Bansil, A.; Eijt, S.W. H. pdf  url
doi  openurl
  Title Nature of the Positron State in CdSe Quantum Dots Type A1 Journal article
  Year 2018 Publication Physical review letters Abbreviated Journal Phys Rev Lett  
  Volume 121 Issue 5 Pages 057401  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) Previous studies have shown that positron-annihilation spectroscopy is a highly sensitive probe of the electronic structure and surface composition of ligand-capped semiconductor quantum dots (QDs) embedded in thin films. The nature of the associated positron state, however, whether the positron is confined inside the QDs or localized at their surfaces, has so far remained unresolved. Our positron-annihilation lifetime spectroscopy studies of CdSe QDs reveal the presence of a strong lifetime component in the narrow range of 358–371 ps, indicating abundant trapping and annihilation of positrons at the surfaces of the QDs. Furthermore, our ab initio calculations of the positron wave function and lifetime employing a recent formulation of the weighted density approximation demonstrate the presence of a positron surface state and predict positron lifetimes close to experimental values. Our study thus resolves the long-standing question regarding the nature of the positron state in semiconductor QDs and opens the way to extract quantitative information on surface composition and ligand-surface interactions of colloidal semiconductor QDs through highly sensitive positron-annihilation techniques.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000440635300012 Publication Date 2018-08-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0031-9007 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 8.462 Times cited 6 Open Access  
  Notes The work at Delft University of Technology was supported by the China Scholarship Council (CSC) grant of W. S. We acknowledge financial support for this research from ADEM, A green Deal in Energy Materials of the Ministry of Economic Affairs of The Netherlands. The PALS study is based upon experiments performed at the PLEPS instrument of the NEPOMUC facility at the Heinz Maier-Leibnitz Zentrum (MLZ), Garching, Germany, and was supported by the European Commission under the 7th Framework Program, Key Action: Strengthening the European Research Area, Research Infrastructures, Contract No. 226507, NMI3. The work at the University of Maine was supported by the National Science Foundation under Grant No. DMR-1206940. V. C. and R. S. were supported by the FWO-Vlaanderen through Project No. G. 0224.14N. Computational resources and services used in this work were in part provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government (EWI Department). The work at Northeastern University was supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences Grant No. DE-FG02-07ER46352 (core research), and benefited from Northeastern University’s Advanced Scientific Computation Center (ASCC), the National Energy Research Scientific Computing Center (NERSC) through DOE Grant No. DE-AC02-05CH11231, and support (functionals for modeling positron spectros- copies of layered materials) from the DOE EFRC: Center for the Computational Design of Functional Layered Materials (CCDM) under DE-SC0012575. Approved Most recent IF: 8.462  
  Call Number CMT @ cmt @c:irua:152999UA @ admin @ c:irua:152999 Serial 5009  
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Author Eijt, S.W.H.; Shi, W.; Mannheim, A.; Butterling, M.; Schut, H.; Egger, W.; Dickmann, M.; Hugenschmidt, C.; Shakeri, B.; Meulenberg, R.W.; Callewaert, V.; Saniz, R.; Partoens, B.; Barbiellini, B.; Bansil, A.; Melskens, J.; Zeman, M.; Smets, A.H.M.; Kulbak, M.; Hodes, G.; Cahen, D.; Brück, E. url  doi
openurl 
  Title New insights into the nanostructure of innovative thin film solar cells gained by positron annihilation spectroscopy Type A1 Journal article
  Year 2017 Publication Journal of physics : conference series Abbreviated Journal  
  Volume 791 Issue 791 Pages 012021  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) Recent studies showed that positron annihilation methods can provide key insights into the nanostructure and electronic structure of thin film solar cells. In this study, positron annihilation lifetime spectroscopy (PALS) is applied to investigate CdSe quantum dot (QD) light absorbing layers, providing evidence of positron trapping at the surfaces of the QDs. This enables one to monitor their surface composition and electronic structure. Further, 2D-Angular Correlation of Annihilation Radiation (2D-ACAR) is used to investigate the nanostructure of divacancies in photovoltaic-high-quality a-Si:H films. The collected momentum distributions were converted by Fourier transformation to the direct space representation of the electron-positron autocorrelation function. The evolution of the size of the divacancies as a function of hydrogen dilution during deposition of a-Si:H thin films was examined. Finally, we present a first positron Doppler Broadening of Annihilation Radiation (DBAR) study of the emerging class of highly efficient thin film solar cells based on perovskites.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000400610500021 Publication Date 2017-02-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1742-6588 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 1 Open Access  
  Notes The work at Delft University of Technology was supported by the China Scholarship Council (CSC) grant of W.S., by ADEM, A green Deal in Energy Materials of the Ministry of Economic Affairs of The Netherlands (www.adem- innovationlab.nl), and the STW Vidi grant of A.S., Grant No. 10782. The PALS study is based upon experiments performed at the PLEPS instrument of the NEPOMUC facility at the Heinz Maier-Leibnitz Zentrum (MLZ), Garching, Germany, and was supported by the European Commission under the 7 th Framework Programme, Key Action: Strengthening the European Research Area, Research Infrastructures, Contract No. 226507, NMI3. The work at University of Maine was supported by the National Science Foundation under Grant No. DMR-1206940. Research at the University of Antwerp was supported by FWO grants G022414N and G015013. The work at Northeastern University was supported by the US Department of Energy (DOE), Office of Science, Basic Energy Sciences grant number DE-FG02-07ER46352 (core research), and benefited from Northeastern University's Advanced Scientific Computation Center (ASCC), the NERSC supercomputing center through DOE grant number DE-AC02-05CH11231, and support (applications to layered materials) from the DOE EFRC: Center for the Computational Design of Functional Layered Materials (CCDM) under DE-SC0012575. The work at the Weizmann Institute was supported by the Sidney E. Frank Foundation through the Israel Science Foundation, by the Israel Ministry of Science, and the Israel National Nano-Initiative. D.C. holds the Sylvia and Rowland Schaefer Chair in Energy Research. Approved Most recent IF: NA  
  Call Number CMT @ cmt @ c:irua:140850 Serial 4426  
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Author Van Boxem, R.; Partoens, B.; Verbeeck, J. url  doi
openurl 
  Title Inelastic electron-vortex-beam scattering Type A1 Journal article
  Year 2015 Publication Physical review : A : atomic, molecular and optical physics Abbreviated Journal Phys Rev A  
  Volume 91 Issue 91 Pages 032703  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract (up) Recent theoretical and experimental developments in the field of electron-vortex-beam physics have raised questions about what exactly this novelty in the field of electron microscopy (and other fields, such as particle physics) really provides. An important part of the answer to these questions lies in scattering theory. The present investigation explores various aspects of inelastic quantum scattering theory for cylindrically symmetric beams with orbital angular momentum. The model system of Coulomb scattering on a hydrogen atom provides the setting to address various open questions: How is momentum transferred? Do vortex beams selectively excite atoms, and how can one employ vortex beams to detect magnetic transitions? The analytical approach presented here provides answers to these questions. OAM transfer is possible, but not through selective excitation; rather, by pre- and postselection one can filter out the relevant contributions to a specific signal.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Lancaster, Pa Editor  
  Language Wos 000351035000004 Publication Date 2015-03-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1050-2947;1094-1622; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.925 Times cited 31 Open Access  
  Notes Fwo; 312483 Esteem2; 278510 Vortex; esteem2jra3 ECASJO; Approved Most recent IF: 2.925; 2015 IF: 2.808  
  Call Number c:irua:123925 c:irua:123925UA @ admin @ c:irua:123925 Serial 1607  
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Author Dabaghmanesh, S.; Sarmadian, N.; Neyts, E.C.; Partoens, B. url  doi
openurl 
  Title A first principles study of p-type defects in LaCrO3 Type A1 Journal article
  Year 2017 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 19 Issue 34 Pages 22870-22876  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract (up) Recently, Sr-doped LaCrO3 has been experimentally introduced as a new p-type transparent conducting oxide. It is demonstrated that substituting Sr for La results in inducing p-type conductivity in LaCrO3. Performing first principles calculations we study the electronic structure and formation energy of various point defects in LaCrO3. Our results for the formation energies show that in addition to Sr, two more divalent defects, Ca and Ba, substituting for La in LaCrO3, behave as shallow acceptors in line with previous experimental reports. We further demonstrate that under oxygen-poor growth conditions, these shallow acceptors will be compensated by intrinsic donor-like defects (an oxygen vacancy and Cr on an oxygen site), but in the oxygen-rich growth regime the shallow acceptors have the lowest formation energies between all considered defects and will lead to p-type conductivity.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Cambridge Editor  
  Language Wos 000408671600026 Publication Date 2017-08-01  
  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 16 Open Access OpenAccess  
  Notes ; This work was supported by SIM vzw, Technologiepark 935, BE-9052 Zwijnaarde, Belgium, within the InterPoCo project of the H-INT-S horizontal program. The computational resources and services were provided by the Flemish Supercomputer Center and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government. ; Approved Most recent IF: 4.123  
  Call Number UA @ lucian @ c:irua:145621 Serial 4735  
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Author Lozano, D.P.; Couet, S.; Petermann, C.; Hamoir, G.; Jochum, J.K.; Picot, T.; Menendez, E.; Houben, K.; Joly, V.; Antohe, V.A.; Hu, M.Y.; Leu, B.M.; Alatas, A.; Said, A.H.; Roelants, S.; Partoens, B.; Milošević, M.V.; Peeters, F.M.; Piraux, L.; Van de Vondel, J.; Vantomme, A.; Temst, K.; Van Bael, M.J. url  doi
openurl 
  Title Experimental observation of electron-phonon coupling enhancement in Sn nanowires caused by phonon confinement effects Type A1 Journal article
  Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 99 Issue 6 Pages 064512  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) Reducing the size of a superconductor below its characteristic length scales can either enhance or suppress its critical temperature (T-c). Depending on the bulk value of the electron-phonon coupling strength, electronic and phonon confinement effects will play different roles in the modification of T-c. Experimentally disentangling each contribution has remained a challenge. We have measured both the phonon density of states and T-c of Sn nanowires with diameters of 18, 35, and 100 nm in order to quantify the effects of phonon confinement on superconductivity. We observe a shift of the phonon frequency towards the low-energy region and an increase in the electron-phonon coupling constant that can account for the measured increase in T-c.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000459322400005 Publication Date 2019-02-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 8 Open Access  
  Notes ; We would like to thanks Jeroen Scheerder and Wout Keijers for their help and assistance during the low-temperature measurements. This work was supported by the Research Foundation Flanders (FWO), the Concerted Research Action (GOA/14/ 007), the Federation Wallonie-Bruxelles (ARC 13/18-052, Supracryst) and the Fonds de la Recherche Scientifique -FNRS under Grant No. T.0006.16. The authors acknowledge Hercules Stichting (Project Nos. AKUL/13/19 and AKUL/13/25). D.P.L. thanks the FWO for financial support. This research used resources of the Advanced Photon Source, a US Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. ; Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:158621 Serial 5212  
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Author Bercx, M.; Mayda, S.; Depla, D.; Partoens, B.; Lamoen, D. pdf  url
doi  openurl
  Title Plasmonic effects in the neutralization of slow ions at a metallic surface Type A1 Journal Article
  Year 2023 Publication Contributions to Plasma Physics Abbreviated Journal Contrib. Plasma Phys  
  Volume Issue Pages  
  Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;  
  Abstract (up) Secondary electron emission is an important process that plays a significant role in several plasma‐related applications. As measuring the secondary electron yield experimentally is very challenging, quantitative modelling of this process to obtain reliable yield data is critical as input for higher‐scale simulations. Here, we build upon our previous work combining density functional theory calculations with a model originally developed by Hagstrum to extend its application to metallic surfaces. As plasmonic effects play a much more important role in the secondary electron emission mechanism for metals, we introduce an approach based on Poisson point processes to include both surface and bulk plasmon excitations to the process. The resulting model is able to reproduce the yield spectra of several available experimental results quite well but requires the introduction of global fitting parameters, which describe the strength of the plasmon interactions. Finally, we use an in‐house developed workflow to calculate the electron yield for a list of elemental surfaces spanning the periodic table to produce an extensive data set for the community and compare our results with more simplified approaches from the literature.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 001067651300001 Publication Date 2023-09-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0863-1042 ISBN Additional Links UA library record; WoS full record  
  Impact Factor 1.6 Times cited Open Access Not_Open_Access  
  Notes We acknowledge the financial support of FWO-Vlaanderen through project G.0216.14N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government-department EWI. Approved Most recent IF: 1.6; 2023 IF: 1.44  
  Call Number EMAT @ emat @c:irua:200330 Serial 8962  
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Author De Sloovere, D.; Safari, M.; Elen, K.; D'Haen, J.; Drozhzhin, O.A.; Abakumov, A.M.; Simenas, M.; Banys, J.; Bekaert, J.; Partoens, B.; Van Bael, M.K.; Hardy, A. pdf  doi
openurl 
  Title Reduced Na2+xTi4O9 composite : a durable anode for sodium-ion batteries Type A1 Journal article
  Year 2018 Publication Chemistry of materials Abbreviated Journal Chem Mater  
  Volume 30 Issue 23 Pages 8521-8527  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) Sodium-ion batteries (SIBs) are potential cost-effective solutions for stationary energy storage applications. Unavailability of suitable anode materials, however, is one of the important barriers to the maturity of SIBs. Here, we report a Na2+xTi4O9/C composite as a promising anode candidate for SIBs with high capacity and cycling stability. This anode is characterized by a capacity of 124 mAh g(-1) (plus 11 mAh g(-1) contributed by carbon black), an average discharge potential of 0.9 V vs Na/Na+, a good rate capability and a high stability (89% capacity retention after 250 cycles at a rate of 1 degrees C). The mechanisms of sodium insertion/deinsertion and of the formation of Na2+xTi4O9/C are investigated with the aid of various ex/in situ characterization techniques. The in situ formed carbon is necessary for the formation of the reduced sodium titanate. This synthesis method may enable the convenient synthesis of other composites of crystalline phases with amorphous carbon.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000453489300014 Publication Date 2018-11-29  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0897-4756 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 9.466 Times cited 7 Open Access  
  Notes ; This work was supported by the FWO (Research Foundation Flanders, project G040116). O.A.D. and A.M.A. are grateful to the Russian Science Foundation for financial support (Grant 17-73-30006). The authors acknowledge Pieter Samyn for Raman spectroscopy, Fulya Ulu Okudur for preliminary TEM, Bart Ruttens for XRD, Hilde Pellaers for SEM, Tom Haeldermans for elemental analysis, and Karen Leyssen and Vera Meynen for physisorption measurements. ; Approved Most recent IF: 9.466  
  Call Number UA @ admin @ c:irua:156235 Serial 5227  
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Author Sivek, J.; Sahin, H.; Partoens, B.; Peeters, F.M. pdf  doi
openurl 
  Title Giant magnetic anisotropy in doped single layer molybdenum disulfide and fluorographene Type A1 Journal article
  Year 2016 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 28 Issue 28 Pages 195301  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) Stable monolayer materials based on existing, well known and stable two-dimensional crystal fluorographene and molybdenum disulfide are predicted to exhibit a huge magnetocrystalline anisotropy when functionalized with adsorbed transition metal atoms at vacant sides. Ab initio calculations within the density-functional theory formalism were performed to investigate the adsorption of the transitional metals in a single S (or F) vacancy of monolayer molybdenum disulfide (or fluorographene). We found strong bonding of the transitional metal atoms to the vacant sites with binding energies ranging from 2.5 to 5.2 eV. Our calculations revealed that these systems with adsorbed metal atoms exhibit a magnetic anisotropy, specifically the structures including Os and Ir show a giant magnetocrystalline anisotropy energy of 31-101 meV. Our results demonstrate the possibility of obtaining stable monolayer materials with huge magnetocrystalline anisotropy based on preexisting, well known and stable two-dimensional crystals: fluorographene and molybdenum disulfide. We believe that the results obtained here are useful not only for deeper understanding of the origin of magnetocrystalline anisotropy but also for the design of monolayer optoelectronic devices with novel functionalities.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos 000374394700007 Publication Date 2016-04-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0953-8984 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.649 Times cited 7 Open Access  
  Notes Approved Most recent IF: 2.649  
  Call Number UA @ lucian @ c:irua:133611 Serial 4185  
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Author Bekaert, J.; Aperis, A.; Partoens, B.; Oppeneer, P.M.; Milošević, M.V. url  doi
openurl 
  Title Evolution of multigap superconductivity in the atomically thin limit : strain-enhanced three-gap superconductivity in monolayer MgB2 Type A1 Journal article
  Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 96 Issue 9 Pages 094510  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) Starting from first principles, we show the formation and evolution of superconducting gaps in MgB2 at its ultrathin limit. Atomically thin MgB2 is distinctly different from bulk MgB2 in that surface states become comparable in electronic density to the bulklike sigma and pi bands. Combining the ab initio electron-phonon coupling with the anisotropic Eliashberg equations, we showthat monolayer MgB2 develops three distinct superconducting gaps, on completely separate parts of the Fermi surface due to the emergent surface contribution. These gaps hybridize nontrivially with every extra monolayer added to the film owing to the opening of additional coupling channels. Furthermore, we reveal that the three-gap superconductivity in monolayer MgB2 is robust over the entire temperature range that stretches up to a considerably high critical temperature of 20 K. The latter can be boosted to >50K under biaxial tensile strain of similar to 4%, which is an enhancement that is stronger than in any other graphene-related superconductor known to date.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos 000410166800008 Publication Date 2017-09-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9969; 2469-9950 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 supported by TOPBOF-UAntwerp, Research Foundation-Flanders (FWO), the Swedish Research Council (VR), and the Rontgen-Angstrom Cluster. The first-principles calculations have been carried out on the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Centre (VSC), supported financially by the Hercules Foundation and the Flemish Government (EWI Department). Eliashberg theory calculations were supported through the Swedish National Infrastructure for Computing (SNIC). ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:145623 Serial 4741  
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Author Peelaers, H.; Partoens, B.; Giantomassi, M.; Rangel, T.; Goossens, E.; Rignanese, G.-M.; Gonze, X.; Peeters, F.M. url  doi
openurl 
  Title Convergence of quasiparticle band structures of Si and Ge nanowires in the GW approximation and the validity of scissor shifts Type A1 Journal article
  Year 2011 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B  
  Volume 83 Issue 4 Pages 045306-045306,6  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract (up) Starting from fully converged density-functional theory calculations, the quasiparticle corrections are calculated for different sized Si and Ge nanowires using the GW approximation. The effectiveness of recently developed techniques in speeding up the convergence of the quasiparticle calculations is demonstrated. The complete quasiparticle band structures are also obtained using an interpolation technique based on maximallylocalized Wannier functions. From the quasiparticle results, we assess the correctness of the commonly applied scissor-shift correction. Dispersion changes are observed, which are also reflected in changes in the effective band masses calculated taking into account quasiparticle corrections.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000286771400004 Publication Date 2011-01-21  
  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 18 Open Access  
  Notes ; We are grateful to Yann Pouillon for valuable technical support with the build system of ABINIT, related to the WANNIER90 library. This work was supported by the Flemish Science Foundation (FWO-Vl) and by the Interuniversity Attraction Poles Program (P6/42)-Belgian State-Belgian Science Policy. X. G. and G.-M. R. acknowledge funding from the EU's 7th Framework Programme through the ETSF I3 e-Infrastructure project (Grant No. 211956), the Communaute francaise de Belgique through the Action de Recherche Concertee 07/12-003 “Nanosystemes hybrides metal-organiques,” and the Wallon Region Project No. 816849 “ European Theoretical Spectroscopy Facility” (WALL ETSF). M. G. acknowledges funding from the FRFC Project No. 2.4.589.09.F. ; Approved Most recent IF: 3.836; 2011 IF: 3.691  
  Call Number UA @ lucian @ c:irua:86905 Serial 510  
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Author Bals, S.; Van Aert, S.; Romero, C.P.; Lauwaet, K.; Van Bael, M.J.; Schoeters, B.; Partoens, B.; Yuecelen, E.; Lievens, P.; Van Tendeloo, G. pdf  url
doi  openurl
  Title Atomic scale dynamics of ultrasmall germanium clusters Type A1 Journal article
  Year 2012 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 3 Issue 897 Pages 897  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract (up) Starting from the gas phase, small clusters can be produced and deposited with huge flexibility with regard to composition, materials choice and cluster size. Despite many advances in experimental characterization, a detailed morphology of such clusters is still lacking. Here we present an atomic scale observation as well as the dynamical behaviour of ultrasmall germanium clusters. Using quantitative scanning transmission electron microscopy in combination with ab initio calculations, we are able to characterize the transition between different equilibrium geometries of a germanium cluster consisting of less than 25 atoms. Seven-membered rings, trigonal prisms and some smaller subunits are identified as possible building blocks that stabilize the structure.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000306099900024 Publication Date 2012-06-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 12.124 Times cited 90 Open Access  
  Notes Fwo; Iap; Iwt Approved Most recent IF: 12.124; 2012 IF: 10.015  
  Call Number UA @ lucian @ c:irua:100340 Serial 183  
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