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Author Zografos, O.; Dutta, S.; Manfrini, M.; Vaysset, A.; Sorée, B.; Naeemi, A.; Raghavan, P.; Lauwereins, R.; Radu, I.P. pdf  doi
openurl 
  Title Non-volatile spin wave majority gate at the nanoscale Type A1 Journal article
  Year 2017 Publication AIP advances T2 – 61st Annual Conference on Magnetism and Magnetic Materials (MMM), OCT 31-NOV 04, 2016, New Orleans, LA Abbreviated Journal Aip Adv  
  Volume 7 Issue 5 Pages 056020  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract A spin wave majority fork-like structure with feature size of 40 nm, is presented and investigated, through micromagnetic simulations. The structure consists of three merging out-of-plane magnetization spin wave buses and four magneto-electric cells serving as three inputs and an output. The information of the logic signals is encoded in the phase of the transmitted spin waves and subsequently stored as direction of magnetization of the magneto-electric cells upon detection. The minimum dimensions of the structure that produce an operational majority gate are identified. For all input combinations, the detection scheme employed manages to capture the majority phase result of the spin wave interference and ignore all reflection effects induced by the geometry of the structure. (C) 2017 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).  
  Address  
  Corporate Author Thesis  
  Publisher Amer inst physics Place of Publication Melville Editor  
  Language Wos (up) 000402797100177 Publication Date 2017-02-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2158-3226 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.568 Times cited 13 Open Access  
  Notes ; ; Approved Most recent IF: 1.568  
  Call Number UA @ lucian @ c:irua:144288 Serial 4673  
Permanent link to this record
 

 
Author Van Pottelberge, R.; Zarenia, M.; Vasilopoulos, P.; Peeters, F.M. url  doi
openurl 
  Title Graphene quantum dot with a Coulomb impurity : subcritical and supercritical regime Type A1 Journal article
  Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 95 Issue 24 Pages 245410  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We study the influence of confinement on the atomic collapse due to a Coulomb impurity placed at the center of a graphene quantum dot of radius R. We apply the zigzag or infinite-mass boundary condition and consider both a point-size and a finite-size impurity. As a function of the impurity strength Za, the energy spectra are discrete. In the case of the zigzag boundary condition, the degenerate (with respect to the angular momentum m) zero-energy levels are pulled down in energy as Z alpha increases, and they remain below epsilon = – Z alpha. Our results show that the energy levels exhibit a 1/R dependence in the subcritical regime [Z alpha < |km + 1/2|, k = 1 (-1) for the K (K') valley]. In the supercritical regime (Z alpha > |km + 1/2|) we find a qualitatively very different behavior where the levels decrease as a function of R in a nonmonotonic manner. While the valley symmetry is preserved in the presence of the impurity, we find that the impurity breaks electron-hole symmetry. We further study the energy spectrum of zigzag quantum dots in gapped graphene. Our results show that as the gap increases, the lowest electron states are pushed into the gap by the impurity.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000403072400005 Publication Date 2017-06-13  
  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 13 Open Access  
  Notes ; We thank Massoud Ramezani-Masir and Dean Moldovan for fruitful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the Methusalem funding of the Flemish Government, and by the Canadian NSERC Grant No. OGP0121756 (P. V.). ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:144197 Serial 4661  
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Author Li, L.L.; Moldovan, D.; Xu, W.; Peeters, F.M. pdf  doi
openurl 
  Title Electric-and magnetic-field dependence of the electronic and optical properties of phosphorene quantum dots Type A1 Journal article
  Year 2017 Publication Nanotechnology Abbreviated Journal Nanotechnology  
  Volume 28 Issue 8 Pages 085702  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Recently, black phosphorus quantum dots were fabricated experimentally. Motivated by these experiments, we theoretically investigate the electronic and optical properties of rectangular phosphorene quantum dots (RPQDs) in the presence of an in-plane electric field and a perpendicular magnetic field. The energy spectra and wave functions of RPQDs are obtained numerically using the tight-binding approach. We find edge states within the band gap of the RPQD which are well separated from the bulk states. In an undoped RPQD and for in-plane polarized light, due to the presence of well-defined edge states, we find three types of optical transitions which are between the bulk states, between the edge and bulk states, and between the edge states. The electric and magnetic fields influence the bulk-to-bulk, edge-to-bulk, and edge-to- edge transitions differently due to the different responses of bulk and edge states to these fields.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Bristol Editor  
  Language Wos (up) 000403100700001 Publication Date 2017-01-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0957-4484 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.44 Times cited 32 Open Access  
  Notes ; This work was financially supported by the China Scholarship Council (CSC), the Flemish Science Foundation (FWO-Vl), the National Natural Science Foundation of China (Grant Nos. 11304316 and 11574319), and by the Chinese Academy of Sciences (CAS). ; Approved Most recent IF: 3.44  
  Call Number UA @ lucian @ c:irua:144325 Serial 4648  
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Author Saniz, R.; Bekaert, J.; Partoens, B.; Lamoen, D. pdf  url
doi  openurl
  Title Structural and electronic properties of defects at grain boundaries in CuInSe2 Type A1 Journal article
  Year 2017 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys  
  Volume 19 Issue 19 Pages 14770-14780  
  Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract We report on a first-principles study of the structural and electronic properties of a Sigma3 (112) grain boundary model in CuInSe2. The study focuses on a coherent, stoichiometry preserving, cation–Se terminated grain boundary, addressing the properties of the grain boundary as such, as well as the effect

of well known defects in CuInSe2. We show that in spite of its apparent simplicity, such a grain boundary exhibits a very rich phenomenology, providing an explanation for several of the experimentally observed properties of grain boundaries in CuInSe2 thin films. In particular, we show that the combined effect of Cu vacancies and cation antisites can result in the observed Cu depletion with no In enrichment at the grain boundaries. Furthermore, Cu vacancies are unlikely to produce a hole barrier at the grain boundaries, but Na may indeed have such an effect. We find that Na-on-Cu defects will tend to form abundantly at

the grain boundaries, and can provide a mechanism for the carrier depletion and/or type inversion experimentally reported.
 
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000403327200059 Publication Date 2017-05-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.123 Times cited 12 Open Access OpenAccess  
  Notes We thank B. Schoeters for his assistance running the GBstudio software. We acknowledge the financial support of FWO-Vlaanderen through project G.0150.13. 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 FWO-Vlaanderen and the Flemish Government-department EWI. Approved Most recent IF: 4.123  
  Call Number EMAT @ emat @ c:irua:143869 Serial 4577  
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Author Ghorbanfekr-Kalashami, H.; Vasu, K.S.; Nair, R.R.; Peeters, F.M.; Neek-Amal, M. url  doi
openurl 
  Title Dependence of the shape of graphene nanobubbles on trapped substance Type A1 Journal article
  Year 2017 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 8 Issue 8 Pages 15844  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Van der Waals (vdW) interaction between two-dimensional crystals (2D) can trap substances in high pressurized (of order 1 GPa) on nanobubbles. Increasing the adhesion between the 2D crystals further enhances the pressure and can lead to a phase transition of the trapped material. We found that the shape of the nanobubble can depend critically on the properties of the trapped substance. In the absence of any residual strain in the top 2D crystal, flat nanobubbles can be formed by trapped long hydrocarbons (that is, hexadecane). For large nanobubbles with radius 130 nm, our atomic force microscopy measurements show nanobubbles filled with hydrocarbons (water) have a cylindrical symmetry (asymmetric) shape which is in good agreement with our molecular dynamics simulations. This study provides insights into the effects of the specific material and the vdW pressure on the microscopic details of graphene bubbles.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000403417500001 Publication Date 2017-06-16  
  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 44 Open Access  
  Notes We acknowledge fruitful discussion with Irina Grigorieva and Andre K. Geim. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program, the Royal Society and the Engineering and Physical Sciences Research Council, UK (EP/K016946/1). M.N.-A. was supported by Iran National Science Foundation (INSF). Approved Most recent IF: 12.124  
  Call Number CMT @ cmt @ c:irua:144189 Serial 4580  
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Author Stosic, D.; Mulkers, J.; Van Waeyenberge, B.; Ludermir, T.B.; Milošević, M.V. url  doi
openurl 
  Title Paths to collapse for isolated skyrmions in few-monolayer ferromagnetic films Type A1 Journal article
  Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 95 Issue 21 Pages 214418  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Magnetic skyrmions are topological spin configurations in materials with chiral Dzyaloshinskii-Moriya interaction (DMI), that are potentially useful for storing or processing information. To date, DMI has been found in few bulk materials, but can also be induced in atomically thin magnetic films in contact with surfaces with large spin-orbit interactions. Recent experiments have reported that isolated magnetic skyrmions can be stabilized even near room temperature in few-atom-thick magnetic layers sandwiched between materials that provide asymmetric spin-orbit coupling. Here we present the minimum-energy path analysis of three distinct mechanisms for the skyrmion collapse, based on ab initio input and the performed atomic-spin simulations. We focus on the stability of a skyrmion in three atomic layers of Co, either epitaxial on the Pt(111) surface or within a hybrid multilayer where DMI nontrivially varies per monolayer due to competition between different symmetry breaking from two sides of the Co film. In laterally finite systems, their constrained geometry causes poor thermal stability of the skyrmion toward collapse at the boundary, which we show to be resolved by designing the high-DMI structure within an extended film with lower or no DMI.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000404015500001 Publication Date 2017-06-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 48 Open Access  
  Notes This work was supported by the Research Foundation, Flanders (FWO-Vlaanderen) and Brazilian agency CNPq (Grants No. 442668/2014-7 and No. 140840/2016-8). Approved Most recent IF: 3.836  
  Call Number CMT @ cmt @c:irua:144865 Serial 4704  
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Author de Araujo, J.L.B.; Munarin, F.F.; Farias, G.A.; Peeters, F.M.; Ferreira, W.P. url  doi
openurl 
  Title Structure and reentrant percolation in an inverse patchy colloidal system Type A1 Journal article
  Year 2017 Publication Physical Review E Abbreviated Journal  
  Volume 95 Issue 6 Pages 062606  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Two-dimensional systems of inverse patchy colloids modeled as disks with a central charge and having their surface decorated with oppositely pointlike charged patches are investigated using molecular dynamics simulations. The self-assembly of the patchy colloids leads to diverse ground state configurations ranging from crystalline arrangements of monomers to linear clusters, ramified linear clusters and to percolated configurations. Two structural phase diagrams are constructed: (1) as a function of the net charge and area fraction, and (2) as a function of the net charge and the range of the pair interaction potential. An interesting reentrant percolation transition is obtained as a function of the net charge of the colloids. We identify distinct mechanisms that lead to the percolation transition.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000404545700005 Publication Date 2017-06-27  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited 5 Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:152628 Serial 8587  
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Author Doevenspeck, J.; Zografos, O.; Gurunarayanan, S.; Lauwereins, R.; Raghavan, P.; Sorée, B. url  doi
openurl 
  Title Design and simulation of plasmonic interference-based majority gate Type A1 Journal article
  Year 2017 Publication AIP advances Abbreviated Journal  
  Volume 7 Issue 6 Pages 065116  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Major obstacles in current CMOS technology, such as the interconnect bottleneck and thermal heat management, can be overcome by employing subwavelength-scaled light in plasmonic waveguides and devices. In this work, a plasmonic structure that implements the majority (MAJ) gate function is designed and thoroughly studied through simulations. The structure consists of three merging waveguides, serving as the MAJ gate inputs. The information of the logic signals is encoded in the phase of transmitted surface plasmon polaritons (SPP). SPPs are excited at all three inputs and the phase of the output SPP is determined by theMAJof the input phases. The operating dimensions are identified and the functionality is verified for all input combinations. This is the first reported simulation of a plasmonic MAJ gate and thus contributes to the field of optical computing at the nanoscale. (C) 2017 Author(s).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000404621200036 Publication Date 2017-06-23  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2158-3226 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:152632 Serial 7764  
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Author Kong, X.; Li, L.; Leenaerts, O.; Liu, X.-J.; Peeters, F.M. url  doi
openurl 
  Title New group-V elemental bilayers : a tunable structure model with four-, six-, and eight-atom rings Type A1 Journal article
  Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 96 Issue 3 Pages 035123  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Two-dimensional group-V elemental materials have attracted widespread attention due to their nonzero band gap while displaying high electron mobility. Using first-principles calculations, we propose a series of new elemental bilayers with group-V elements (Bi, Sb, As). Our study reveals the dynamical stability of four-, six-, and eight-atom ring structures, demonstrating their possible coexistence in such bilayer systems. The proposed structures for Sb and As are large-gap semiconductors that are potentially interesting for applications in future nanodevices. The Bi structures have nontrivial topological properties with a direct nontrivial band gap. The nontrivial gap is shown to arise from a band inversion at the Brillouin zone center due to the strong intrinsic spin-orbit coupling in Bi atoms. Moreover, we demonstrate the possibility of tuning the properties of these materials by enhancing the ratio of six-atom rings to four-and eight-atom rings, which results in wider nontrivial band gaps and lower formation energies.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000405363900005 Publication Date 2017-07-14  
  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 14 Open Access  
  Notes ; This work is supported by Ministry of Science and Technology of China (MOST) (Grant No. 2016YFA0301604), National Natural Science Foundation of China (NSFC) ( No. 11574008), the Thousand-Young-Talent Program of China, and the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government – department EWI, and the National Supercomputing Center in Tianjin, funded by the Collaborative Innovation Center of Quantum Matter. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:144834 Serial 4721  
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Author Lundeberg, M.B.; Gao, Y.; Asgari, R.; Tan, C.; Van Duppen, B.; Autore, M.; Alonso-Gonzalez, P.; Woessner, A.; Watanabe, K.; Taniguchi, T.; Hillenbrand, R.; Hone, J.; Polini, M.; Koppens, F.H.L. pdf  doi
openurl 
  Title Tuning quantum nonlocal effects in graphene plasmonics Type A1 Journal article
  Year 2017 Publication Science Abbreviated Journal Science  
  Volume 357 Issue 6347 Pages 187-190  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract The response of electron systems to electrodynamic fields that change rapidly in space is endowed by unique features, including an exquisite spatial nonlocality. This can reveal much about the materials' electronic structure that is invisible in standard probes that use gradually varying fields. Here, we use graphene plasmons, propagating at extremely slow velocities close to the electron Fermi velocity, to probe the nonlocal response of the graphene electron liquid. The near-field imaging experiments reveal a parameter-free match with the full quantum description of the massless Dirac electron gas, which involves three types of nonlocal quantum effects: single-particle velocity matching, interaction-enhanced Fermi velocity, and interaction-reduced compressibility. Our experimental approach can determine the full spatiotemporal response of an electron system.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington, D.C. Editor  
  Language Wos (up) 000405391700042 Publication Date 2017-07-19  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0036-8075; 1095-9203 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 37.205 Times cited 87 Open Access  
  Notes ; F.H.L.K., M.P., and R.H. acknowledge support by the European Union Seventh Framework Programme under grant agreement no. 696656 Graphene Flagship. M. P. acknowledges support by Fondazione Istituto Italiano di Tecnologia. F. H. L. K. acknowledges financial support from the European Union Seventh Framework Programme under the ERC starting grant (307806, CarbonLight) and project GRASP (FP7-ICT-2013-613024-GRASP). F. H. L. K. acknowledges support from the Spanish Ministry of Economy and Competitiveness, through the “ Severo Ochoa” Programme for Centres of Excellence in R& D (SEV-2015-0522), support by Fundacio Cellex Barcelona, CERCA Programme/Generalitat de Catalunya, the Mineco grants Ramon y Cajal (RYC-2012-12281), Plan Nacional (FIS2013-47161-P and FIS2014-59639-JIN), and support from the Government of Catalonia through the SGR grant (2014-SGR-1535). R. H. acknowledges support from the Spanish Ministry of Economy and Competitiveness (national project MAT-2015-65525-R). P. A-G. acknowledges financial support from the national project FIS2014-60195-JIN and the ERC starting grant 715496, 2DNANOPTICA. K. W. and T. T. acknowledge support from the Elemental Strategy Initiative conducted by the MEXT, Japan, and JSPS KAKENHI grant numbers JP26248061, JP15K21722, and JP25106006. Y. G., C. T., and J. H. acknowledge support from the U. S. Office of Naval Research N00014-13-1-0662. C. T. was supported under contract FA9550-11-C-0028 and awarded by the Department of Defense, Air Force Office of Scientific Research, National Defense Science and Engineering Graduate (NDSEG) Fellowship, 32 CFR 168a. This research used resources of the Center for Functional Nanomaterials, which is a U. S. Department of Energy Office of Science Facility at Brookhaven National Laboratory under contract no. DE-SC0012704. B. V. D. acknowledges support from the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship. M. P. is extremely grateful for the financial support granted by ICFO during a visit in August 2016. This work used open source software (www. python. org, www. matplotlib. org, and www. blender. org). R. H. is cofounder of Neaspec GmbH, a company producing scattering-type scanning near-field optical microscope systems such as the ones used in this study. All other authors declare no competing financial interests. ; Approved Most recent IF: 37.205  
  Call Number UA @ lucian @ c:irua:144833 Serial 4730  
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Author Chirayath, V.A.; Callewaert, V.; Fairchild, A.J.; Chrysler, M.D.; Gladen, R.W.; Mcdonald, A.D.; Imam, S.K.; Shastry, K.; Koymen, A.R.; Saniz, R.; Barbiellini, B.; Rajeshwar, K.; Partoens, B.; Weiss, A.H. pdf  url
doi  openurl
  Title Auger electron emission initiated by the creation of valence-band holes in graphene by positron annihilation Type A1 Journal article
  Year 2017 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 8 Issue 8 Pages 16116  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Auger processes involving the filling of holes in the valence band are thought to make important contributions to the low-energy photoelectron and secondary electron spectrum from many solids. However, measurements of the energy spectrum and the efficiency with which electrons are emitted in this process remain elusive due to a large unrelated background resulting from primary beam-induced secondary electrons. Here, we report the direct measurement of the energy spectra of electrons emitted from single layer graphene as a result of the decay of deep holes in the valence band. These measurements were made possible by eliminating competing backgrounds by employing low-energy positrons (<1.25 eV) to create valence-band holes by annihilation. Our experimental results, supported by theoretical calculations, indicate that between 80 and 100% of the deep valence-band holes in graphene are filled via an Auger transition.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000405398200001 Publication Date 2017-07-13  
  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 20 Open Access  
  Notes The experiments in this work were supported by the grant NSF DMR 1508719. A.H.W and A.R.K. gratefully acknowledge support for the building of advanced positron beam through the grant NSF DMR MRI 1338130. V.C. and R.S. were supported by the FWO-Vlaanderen through Project No. G. 0224.14N. The 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 Hercules Foundation and the Flemish Government (EWI Department). 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. Approved Most recent IF: 12.124  
  Call Number CMT @ cmt @ c:irua:144625 Serial 4627  
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Author Van der Donck, M.; Zarenia, M.; Peeters, F.M. pdf  url
doi  openurl
  Title Excitons and trions in monolayer transition metal dichalcogenides : a comparative study between the multiband model and the quadratic single-band model Type A1 Journal article
  Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 96 Issue 3 Pages 035131  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The electronic and structural properties of excitons and trions in monolayer transition metal dichalcogenides are investigated using both a multiband and a single- band model. In the multiband model we construct the excitonic Hamiltonian in the product base of the single-particle states at the conduction and valence band edges. We decouple the corresponding energy eigenvalue equation and solve the resulting differential equation self-consistently, using the finite element method (FEM), to determine the energy eigenvalues and the wave functions. As a comparison, we also consider the simple single-band model which is often used in numerical studies. We solve the energy eigenvalue equation using the FEM as well as with the stochastic variational method (SVM) in which a variational wave function is expanded in a basis of a large number of correlated Gaussians. We find good agreement between the results of both methods, as well as with other theoretical works for excitons, and we also compare with available experimental data. For trions the agreement between both methods is not as good due to our neglect of angular correlations when using the FEM. Finally, when comparing the two models, we see that the presence of the valence bands in the mutiband model leads to differences with the single- band model when (interband) interactions are strong.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000405706600005 Publication Date 2017-07-18  
  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 50 Open Access  
  Notes ; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:145209 Serial 4716  
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Author Domingos, J.L.C.; Peeters, F.M.; Ferreira, W.P. pdf  doi
openurl 
  Title Self-assembly of rigid magnetic rods consisting of single dipolar beads in two dimensions Type A1 Journal article
  Year 2017 Publication Physical review E Abbreviated Journal Phys Rev E  
  Volume 96 Issue 1 Pages 012603  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Molecular dynamics simulations are used to investigate the structural properties of a two-dimensional ensemble of magnetic rods, which are modeled as aligned single dipolar beads. The obtained self-assembled configurations can be characterized as (1) clusters, (2) percolated, and (3) ordered structures, and their structural properties are investigated in detail. By increasing the aspect ratio of the magnetic rods, we show that the percolation transition is suppressed due to the reduced mobility of the rods in two dimensions. Such a behavior is opposite to the one observed in three dimensions. A magnetic bulk phase is found with local ferromagnetic order and an unusual nonmonotonic behavior of the nematic order is observed.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000405713900014 Publication Date 2017-07-18  
  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 8 Open Access  
  Notes ; This work was supported by the Brazilian agencies FUNCAP, CAPES, program Science without borders, and CNPq (Project No. 400748/2013-4), the joint CNPq-FWO bilateral project, and the Flemish Science Foundation (FWO-V1). ; Approved Most recent IF: 2.366  
  Call Number UA @ lucian @ c:irua:145210 Serial 4723  
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Author Magnus, W.; Lemmens, L.; Brosens, F. pdf  doi
openurl 
  Title Quantum canonical ensemble : a projection operator approach Type A1 Journal article
  Year 2017 Publication Physica: A : theoretical and statistical physics Abbreviated Journal Physica A  
  Volume 482 Issue Pages 1-13  
  Keywords A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT)  
  Abstract Knowing the exact number of particles N, and taking this knowledge into account, the quantum canonical ensemble imposes a constraint on the occupation number operators. The constraint particularly hampers the systematic calculation of the partition function and any relevant thermodynamic expectation value for arbitrary but fixed N. On the other hand, fixing only the average number of particles, one may remove the above constraint and simply factorize the traces in Fock space into traces over single-particle states. As is well known, that would be the strategy of the grand-canonical ensemble which, however, comes with an additional Lagrange multiplier to impose the average number of particles. The appearance of this multiplier can be avoided by invoking a projection operator that enables a constraint-free computation of the partition function and its derived quantities in the canonical ensemble, at the price of an angular or contour integration. Introduced in the recent past to handle various issues related to particle-number projected statistics, the projection operator approach proves beneficial to a wide variety of problems in condensed matter physics for which the canonical ensemble offers a natural and appropriate environment. In this light, we present a systematic treatment of the canonical ensemble that embeds the projection operator into the formalism of second quantization while explicitly fixing N, the very number of particles rather than the average. Being applicable to both bosonic and fermionic systems in arbitrary dimensions, transparent integral representations are provided for the partition function Z(N) and the Helmholtz free energy F-N as well as for two- and four-point correlation functions. The chemical potential is not a Lagrange multiplier regulating the average particle number but can be extracted from FN+1 – F-N, as illustrated for a two-dimensional fermion gas. (C) 2017 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Amsterdam Editor  
  Language Wos (up) 000405885500001 Publication Date 2017-04-20  
  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 1 Open Access  
  Notes ; ; Approved Most recent IF: 2.243  
  Call Number UA @ lucian @ c:irua:145145 Serial 4722  
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Author Embon, L.; Anahory, Y.; Jelić, Z.L.; Lachman, E.O.; Myasoedov, Y.; Huber, M.E.; Mikitik, G.P.; Silhanek, A.V.; Milošević, M.V.; Gurevich, A.; Zeldov, E. url  doi
openurl 
  Title Imaging of super-fast dynamics and flow instabilities of superconducting vortices Type A1 Journal article
  Year 2017 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 8 Issue Pages 85  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Quantized magnetic vortices driven by electric current determine key electromagnetic properties of superconductors. While the dynamic behavior of slow vortices has been thoroughly investigated, the physics of ultrafast vortices under strong currents remains largely unexplored. Here, we use a nanoscale scanning superconducting quantum interference device to image vortices penetrating into a superconducting Pb film at rates of tens of GHz and moving with velocities of up to tens of km/s, which are not only much larger than the speed of sound but also exceed the pair-breaking speed limit of superconducting condensate. These experiments reveal formation of mesoscopic vortex channels which undergo cascades of bifurcations as the current and magnetic field increase. Our numerical simulations predict metamorphosis of fast Abrikosov vortices into mixed Abrikosov-Josephson vortices at even higher velocities. This work offers an insight into the fundamental physics of dynamic vortex states of superconductors at high current densities, crucial for many applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000405900400002 Publication Date 2017-07-13  
  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 124 Open Access  
  Notes ; We would like to thank M.L. Rappaport for fruitful discussions and technical support. This work was supported by the US-Israel Binational Science Foundation (BSF) grant No. 2014155 and the Israel Science Foundation grant No. 132/14. A.G. was also supported by the United States Department of Energy under Grant No. DE-SC0010081. M.V.M. acknowledges support from Research Foundation-Flanders (FWO). The work of Z.L.J. and A.V.S. was partially supported by “Mandat d'Impulsion Scientifique” MIS F.4527.13 of the F.R.S.-FNRS. This work benefited from the support of COST action MP-1201. ; Approved Most recent IF: 12.124  
  Call Number UA @ lucian @ c:irua:144832 Serial 4720  
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Author Kandemir, A.; Ozden, A.; Cagin, T.; Sevik, C. doi  openurl
  Title Thermal conductivity engineering of bulk and one-dimensional Si-Ge nanoarchitectures Type A1 Journal article
  Year 2017 Publication Science and technology of advanced materials Abbreviated Journal  
  Volume 18 Issue 1 Pages 187-196  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Various theoretical and experimental methods are utilized to investigate the thermal conductivity of nanostructured materials; this is a critical parameter to increase performance of thermoelectric devices. Among these methods, equilibrium molecular dynamics (EMD) is an accurate technique to predict lattice thermal conductivity. In this study, by means of systematic EMD simulations, thermal conductivity of bulk Si-Ge structures (pristine, alloy and superlattice) and their nanostructured one dimensional forms with square and circular cross-section geometries (asymmetric and symmetric) are calculated for different crystallographic directions. A comprehensive temperature analysis is evaluated for selected structures as well. The results show that one-dimensional structures are superior candidates in terms of their low lattice thermal conductivity and thermal conductivity tunability by nanostructuring, such as by diameter modulation, interface roughness, periodicity and number of interfaces. We find that thermal conductivity decreases with smaller diameters or cross section areas. Furthermore, interface roughness decreases thermal conductivity with a profound impact. Moreover, we predicted that there is a specific periodicity that gives minimum thermal conductivity in symmetric superlattice structures. The decreasing thermal conductivity is due to the reducing phonon movement in the system due to the effect of the number of interfaces that determine regimes of ballistic and wave transport phenomena. In some nanostructures, such as nanowire superlattices, thermal conductivity of the Si/Ge system can be reduced to nearly twice that of an amorphous silicon thermal conductivity. Additionally, it is found that one crystal orientation, <100>, is better than the <111> crystal orientation in one-dimensional and bulk SiGe systems. Our results clearly point out the importance of lattice thermal conductivity engineering in bulk and nanostructures to produce high-performance thermoelectric materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000405949800001 Publication Date 2017-03-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1468-6996; 1878-5514 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor Times cited Open Access  
  Notes Approved no  
  Call Number UA @ admin @ c:irua:193772 Serial 8662  
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Author Zebrowski, D.P.; Peeters, F.M.; Szafran, B. url  doi
openurl 
  Title Double quantum dots defined in bilayer graphene Type A1 Journal article
  Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 96 Issue 3 Pages 035434  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Artificial molecular states of double quantum dots defined in bilayer graphene are studied with the atomistic tight-binding method and its low-energy continuum approximation. We indicate that the extended electron wave functions have opposite parities on sublattices of the layers and that the ground-state wave-function components change from bonding to antibonding with the interdot distance. In the weak-coupling limit, the one most relevant for quantum dots defined electrostatically, the signatures of the interdot coupling include, for the two-electron ground state, formation of states with symmetric or antisymmetric spatial wave functions split by the exchange energy. In the high-energy part of the spectrum the states with both electrons in the same dot are found with the splitting of energy levels corresponding to simultaneous tunneling of the electron pair from one dot to the other.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000406284200005 Publication Date 2017-07-26  
  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 6 Open Access  
  Notes ; ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:145758 Serial 4739  
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Author Milovanović, S.P.; Tadic, M.Z.; Peeters, F.M. doi  openurl
  Title Graphene membrane as a pressure gauge Type A1 Journal article
  Year 2017 Publication Applied physics letters Abbreviated Journal Appl Phys Lett  
  Volume 111 Issue 4 Pages 043101  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Straining graphene results in the appearance of a pseudo-magnetic field which alters its local electronic properties. Applying a pressure difference between the two sides of the membrane causes it to bend/bulge resulting in a resistance change. We find that the resistance changes linearly with pressure for bubbles of small radius while the response becomes non-linear for bubbles that stretch almost to the edges of the sample. This is explained as due to the strong interference of propagating electronic modes inside the bubble. Our calculations show that high gauge factors can be obtained in this way which makes graphene a good candidate for pressure sensing. Published by AIP Publishing.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos (up) 000406779700035 Publication Date 2017-07-24  
  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 11 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Methusalem program, the Erasmus+ programme, and the Serbian Ministry of Education, Science and Technological Development. ; Approved Most recent IF: 3.411  
  Call Number UA @ lucian @ c:irua:145202 Serial 4718  
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Author Ghorbanfekr-Kalashami, H.; Peeters, F.M.; Novoselov, K.S.; Neek-Amal, M. pdf  url
doi  openurl
  Title Spatial design and control of graphene flake motion Type A1 Journal article
  Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 96 Issue 6 Pages 060101  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000406860300001 Publication Date 2017-08-04  
  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 3 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program. M.N.-A. was supported by Iran National Science Foundation (INSF). K.S.N. was supported by the EU Graphene Flagship Program, European Research Council Synergy Grant Hetero2D, the Royal Society, Engineering and Physical Research Council (UK), US Army Research Office. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:145166 Serial 4724  
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Author Xiao, Y.M.; Xu, W.; Peeters, F.M.; Van Duppen, B. url  doi
openurl 
  Title Multicomponent plasmons in monolayer MoS2 with circularly polarized optical pumping Type A1 Journal article
  Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 96 Issue 8 Pages 085405  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract By making use of circularly polarized light and electrostatic gating, monolayer molybdenum disulfide (ML – MoS2) can form a platform supporting multiple types of charge carriers. They can be discriminated by their spin, valley index, or whether they are electrons or holes. We investigate the collective properties of those charge carriers and are able to identify distinct plasmon modes. We analyze the corresponding dispersion relation, lifetime, and oscillator strength, and calculate the phase relation between the oscillations in the different components of the plasmon modes. All platforms in ML-MoS2 support a long-wavelength root q plasmon branch at zero kelvins. In addition to this, for an n-component system, n-1 distinct plasmon modes appear as acoustic modes with linear dispersion in the long-wavelength limit. These modes correspond to out-of-phase oscillations in the different fermion liquids and have, although being damped, a relatively long lifetime. Additionally, we also find distinct modes at large wave vectors that are more strongly damped by intraband processes.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000406861600001 Publication Date 2017-08-04  
  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 2 Open Access  
  Notes ; Y.M.X. acknowledges financial support from the China Scholarship Council (CSC). B.V.D. is supported by the Flemish Science Foundation (FWO-Vl) through a postdoctoral fellowship. This work was also supported by the National Natural Science Foundation of China (Grants No. 11574319 and No. 11304272), the Ministry of Science and Technology of China (Grant No. 2011YQ130018), the Department of Science and Technology of Yunnan Province, the Applied Basic Research Foundation of Yunnan Province (2013FD003), and the Chinese Academy of Sciences. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:145729 Serial 4745  
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Author Sevik, C.; Wallbank, J.R.; Gulseren, O.; Peeters, F.M.; Çakir, D. pdf  doi
openurl 
  Title Gate induced monolayer behavior in twisted bilayer black phosphorus Type A1 Journal article
  Year 2017 Publication 2D materials Abbreviated Journal 2D Mater  
  Volume 4 Issue 3 Pages 035025  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Optical and electronic properties of black phosphorus strongly depend on the number of layers and type of stacking. Using first-principles calculations within the framework of density functional theory, we investigate the electronic properties of bilayer black phosphorus with an interlayer twist angle of 90 degrees. These calculations are complemented with a simple (k) over right arrow . (p) over right arrow model which is able to capture most of the low energy features and is valid for arbitrary twist angles. The electronic spectrum of 90 degrees twisted bilayer black phosphorus is found to be x-y isotropic in contrast to the monolayer. However x-y anisotropy, and a partial return to monolayer-like behavior, particularly in the valence band, can be induced by an external out-of-plane electric field. Moreover, the preferred hole effective mass can be rotated by 90 degrees simply by changing the direction of the applied electric field. In particular, a +0.4 (-0.4) V angstrom(1) out-of-plane electric field results in a similar to 60% increase in the hole effective mass along the y (x) axis and enhances the m(y)*/m(x)* (m(x)*/m(y)*) ratio as much as by a factor of 40. Our DFT and (k) over right arrow . (p) over right arrow simulations clearly indicate that the twist angle in combination with an appropriate gate voltage is a novel way to tune the electronic and optical properties of bilayer phosphorus and it gives us a new degree of freedom to engineer the properties of black phosphorus based devices.  
  Address  
  Corporate Author Thesis  
  Publisher IOP Publishing Place of Publication Bristol Editor  
  Language Wos (up) 000406926600001 Publication Date 2017-08-03  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2053-1583 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.937 Times cited 13 Open Access  
  Notes ; This work was supported by the bilateral project between the The Scientific and Technological Research Council of Turkey (TUBITAK) and FWO-Flanders, Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TRGrid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. We acknowledge the support from TUBITAK (Grant No. 115F024), ERC Synergy grant Hetero2D and the EU Graphene Flagship Project. We also thank Vladimir Fal'ko for helpful discussions. ; Approved Most recent IF: 6.937  
  Call Number UA @ lucian @ c:irua:145151 Serial 4717  
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Author Saberi-Pouya, S.; Vazifehshenas, T.; Salavati-Fard, T.; Farmanbar, M.; Peeters, F.M. url  doi
openurl 
  Title Strong anisotropic optical conductivity in two-dimensional puckered structures : the role of the Rashba effect Type A1 Journal article
  Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 96 Issue 7 Pages 075411  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract within the Kubo formalism. We show that the anisotropic Rashba effect caused by an external field significantly changes the magnitude of the spin splitting. Furthermore, we obtain an analytical expression for the longitudinal optical conductivity associated with interband transitions as a function of the frequency for arbitrary polarization angle. We find that the diagonal components of the optical conductivity tensor are direction dependent and the optical absorption spectrum exhibits a strongly anisotropic absorption window. The height and width of this absorption window are very sensitive to the anisotropy of the system. While the height of absorption peak increases with increasing effective mass anisotropy ratio, the peak intensity is larger when the light polarization is along the armchair direction. Moreover, the absorption peak width becomes broader as the density-of-states mass or Rashba interaction is enhanced. These features in the optical absorption spectrum can be used to determine parameters relevant for spintronics.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000407097100005 Publication Date 2017-08-09  
  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 16 Open Access  
  Notes ; ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:145725 Serial 4752  
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Author Callewaert, V.; Saniz, R.; Barbiellini, B.; Bansil, A.; Partoens, B. pdf  url
doi  openurl
  Title Application of the weighted-density approximation to the accurate description of electron-positron correlation effects in materials Type A1 Journal article
  Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 96 Issue 8 Pages 085135  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We discuss positron-annihilation lifetimes for a set of illustrative bulk materials within the framework of the weighted-density approximation (WDA). The WDA can correctly describe electron-positron correlations in strongly inhomogeneous systems, such as surfaces, where the applicability of (semi-)local approximations is limited. We analyze the WDA in detail and show that the electrons which cannot screen external charges efficiently, such as the core electrons, cannot be treated accurately via the pair correlation of the homogeneous electron gas. We discuss how this problem can be addressed by reducing the screening in the homogeneous electron gas by adding terms depending on the gradient of the electron density. Further improvements are obtained when core electrons are treated within the LDA and the valence electron using the WDA. Finally, we discuss a semiempirical WDA-based approach in which a sum rule is imposed to reproduce the experimental lifetimes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000408342600003 Publication Date 2017-08-24  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9950 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.836 Times cited 6 Open Access  
  Notes Fonds Wetenschappelijk Onderzoek, G. 0224.14N ; U.S. Department of Energy, DE-FG02-07ER46352 DE-AC02-05CH11231 DE-SC0012575 ; Approved Most recent IF: 3.836  
  Call Number CMT @ cmt @c:irua:145703 Serial 4703  
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Author Rezaei, M.; Sisakht, E.T.; Fazileh, F.; Aslani, Z.; Peeters, F.M. url  doi
openurl 
  Title Tight-binding model investigation of the biaxial strain induced topological phase transition in GeCH3 Type A1 Journal article
  Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 96 Issue 8 Pages 085441  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We propose a tight-binding (TB) model, that includes spin-orbit coupling (SOC), to describe the electronic properties of methyl-substituted germanane (GeCH3). This model gives an electronic spectrum in agreement with first principle results close to the Fermi level. Using the Z(2) formalism, we show that a topological phase transition from a normal insulator (NI) to a quantum spin Hall (QSH) phase occurs at 11.6% biaxial tensile strain. The sensitivity of the electronic properties of this system on strain, in particular its transition to the topological insulating phase, makes it very attractive for applications in strain sensors and other microelectronic applications.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000408570800004 Publication Date 2017-08-29  
  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 10 Open Access  
  Notes ; ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:145697 Serial 4755  
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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 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 (up) 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 Saberi-Pouya, S.; Vazifehshenas, T.; Salavati-fard, T.; Farmanbar, M. url  doi
openurl 
  Title Anisotropic hybrid excitation modes in monolayer and double-layer phosphorene on polar substrates Type A1 Journal article
  Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 96 Issue 11 Pages 115402  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We investigate the anisotropic hybrid surface optical (SO) phonon-plasmon dispersion relations in monolayer and double-layer phosphorene systems located on the polar substrates, such as SiO2, h-BN, and Al2O3. We calculate these hybrid modes by using the dynamical dielectric function in the random phase approximation in which the electron-electron interaction and long-range electric field generated by the substrate SO phonons via Frohlich interaction are taken into account. In the long-wavelength limit, we obtain some analytical expressions for the hybrid SO phonon-plasmon dispersion relations which agree with those obtained from the loss function. Our results indicate a strong anisotropy in SO phonon-plasmon modes, which are stronger along the light-mass direction in our heterostructures. Furthermore, we find that the type of substrate has a significant effect on the dispersion relations of the coupled modes. Importantly, the hybrid excitations are apparently sensitive to the misalignment and separation between layers in double-layer phosphorene.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000408826200004 Publication Date 2017-09-01  
  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 6 Open Access  
  Notes ; ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:145665 Serial 4737  
Permanent link to this record
 

 
Author Michel, K.H.; Scuracchio, P.; Peeters, F.M. url  doi
openurl 
  Title Sound waves and flexural mode dynamics in two-dimensional crystals Type A1 Journal article
  Year 2017 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 96 Issue 9 Pages 094302  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Starting from a Hamiltonian with anharmonic coupling between in-plane acoustic displacements and outof-plane (flexural) modes, we derived coupled equations of motion for in-plane displacements correlations and flexural mode density fluctuations. Linear response theory and time-dependent thermal Green's functions techniques are applied in order to obtain different response functions. As external perturbations we allow for stresses and thermal heat sources. The displacement correlations are described by a Dyson equation where the flexural density distribution enters as an additional perturbation. The flexural density distribution satisfies a kinetic equation where the in-plane lattice displacements act as a perturbation. In the hydrodynamic limit this system of coupled equations is at the basis of a unified description of elastic and thermal phenomena, such as isothermal versus adiabatic sound motion and thermal conductivity versus second sound. The general theory is formulated in view of application to graphene, two-dimensional h-BN, and 2H-transition metal dichalcogenides and oxides.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000409246200003 Publication Date 2017-09-05  
  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 6 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:145630 Serial 4751  
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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 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 (up) 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 Zarenia, M.; Neilson, D.; Peeters, F.M. url  doi
openurl 
  Title Inhomogeneous phases in coupled electron-hole bilayer graphene sheets : charge density waves and coupled wigner crystals Type A1 Journal article
  Year 2017 Publication Scientific reports Abbreviated Journal Sci Rep-Uk  
  Volume 7 Issue Pages 11510  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Recently proposed accurate correlation energies are used to determine the phase diagram of strongly coupled electron-hole graphene bilayers. The control parameters of the phase diagram are the charge carrier density and the insulating barrier thickness separating the bilayers. In addition to the electron-hole superfluid phase we find two new inhomogeneous ground states, a one dimensional charge density wave phase and a coupled electron-hole Wigner crystal. The elementary crystal structure of bilayer graphene plays no role in generating these new quantum phases, which are completely determined by the electrons and holes interacting through the Coulomb interaction. The experimental parameters for the new phases lie within attainable ranges and therefore coupled electron-hole bilayer graphene presents itself as an experimental system where novel emergent many-body phases can be realized.  
  Address  
  Corporate Author Thesis  
  Publisher Nature Publishing Group Place of Publication London Editor  
  Language Wos (up) 000410739000008 Publication Date 2017-09-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.259 Times cited 13 Open Access  
  Notes ; We thank Alex Hamilton, Bart Partoens, and Andrea Perali for useful discussions. This work was partially supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program of the Flemish government. D.N. acknowledges support by the University of Camerino FAR project CESEMN. ; Approved Most recent IF: 4.259  
  Call Number UA @ lucian @ c:irua:145620 Serial 4742  
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Author Abdullah, H.M.; Van Duppen, B.; Zarenia, M.; Bahlouli, H.; Peeters, F.M. pdf  doi
openurl 
  Title Quantum transport across van der Waals domain walls in bilayer graphene Type A1 Journal article
  Year 2017 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 29 Issue 42 Pages 425303  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Bilayer graphene can exhibit deformations such that the two graphene sheets are locally detached from each other resulting in a structure consisting of domains with different van der Waals inter-layer coupling. Here we investigate how the presence of these domains affects the transport properties of bilayer graphene. We derive analytical expressions for the transmission probability, and the corresponding conductance, across walls separating different inter-layer coupling domains. We find that the transmission can exhibit a valley-dependent layer asymmetry and that the domain walls have a considerable effect on the chiral tunnelling properties of the charge carriers. We show that transport measurements allow one to obtain the strength with which the two layers are coupled. We perform numerical calculations for systems with two domain walls and find that the availability of multiple transport channels in bilayer graphene significantly modifies the conductance dependence on inter-layer potential asymmetry.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos (up) 000410958400001 Publication Date 2017-07-24  
  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 15 Open Access  
  Notes ; HMA and HB acknowledge the Saudi Center for Theoretical Physics (SCTP) for their generous support and the support of KFUPM under physics research group projects RG1502-1 and RG1502-2. This work is supported by the Flemish Science Foundation (FWO-VI) by a post-doctoral fellowship (BVD). ; Approved Most recent IF: 2.649  
  Call Number UA @ lucian @ c:irua:146664 Serial 4793  
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