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Author Hu, L.; Amini, M.N.; Wu, Y.; Jin, Z.; Yuan, J.; Lin, R.; Wu, J.; Dai, Y.; He, H.; Lu, Y.; Lu, J.; Ye, Z.; Han, S.-T.; Ye, J.; Partoens, B.; Zeng, Y.-J.; Ruan, S. pdf  doi
openurl 
  Title Charge transfer doping modulated raman scattering and enhanced stability of black phosphorus quantum dots on a ZnO nanorod Type A1 Journal article
  Year 2018 Publication Advanced Optical Materials Abbreviated Journal Adv Opt Mater  
  Volume 6 Issue 15 Pages 1800440  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract Black phosphorus (BP) has recently triggered an unprecedented interest in the 2D community. However, many of its unique properties are not exploited and the well-known environmental vulnerability is not conquered. Herein, a type-I mixed-dimensional (0D-1D) van der Waals heterojunction is developed, where three-atomic-layer BP quantum dots (QDs) are assembled on a single ZnO nanorod (NR). By adjusting the indium (In) content in ZnO NRs, the degree and even the direction of surface charge transfer doping within the heterojunction can be tuned, which result in selective Raman scattering enhancements between ZnO and BP. The maximal enhancement factor is determined as 4340 for BP QDs with sub-ppm level. Furthermore, an unexpected long-term ambient stability (more than six months) of BP QDs is revealed, which is ascribed to the electron doping from ZnO:In NRs. The first demonstration of selective Raman enhancements between two inorganic semiconductors as well as the improved stability of BP shed light on this emerging 2D material.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000440815200023 Publication Date 2018-05-18  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2195-1071 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.875 Times cited 37 Open Access Not_Open_Access  
  Notes ; L. Hu and M. N. Amini contributed equally to this work. This work was supported by the National Natural Science Foundation of China under Grant Nos. 51502178, 81571763 and 81622026, the Shenzhen Science and Technology Project under Grant Nos. JCYJ20150324141711644, JCYJ20170412105400428, KQJSCX20170727101208249 and JCYJ20170302153853962. Parts of the computational calculations were carried out using the HPC infrastructure at University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center VSC, supported financially by the FWO-Vlaanderen and the Flemish Government (EWI Department). L. H. acknowledges the PhD Start-up Fund of Natural Science Foundation of Guangdong Province under Grand No. 2017A030310072. J. Y. acknowledges the funding of Shanghai Jiao Tong University (Nos. YG2016MS51 and YG2017MS54). ; Approved Most recent IF: 6.875  
  Call Number UA @ lucian @ c:irua:153112UA @ admin @ c:irua:153112 Serial 5082  
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Author Dabral, A.; Pourtois, G.; Sankaran, K.; Magnus, W.; Yu, H.; de de Meux, A.J.; Lu, A.K.A.; Clima, S.; Stokbro, K.; Schaekers, M.; Collaert, N.; Horiguchi, N.; Houssa, M. doi  openurl
  Title Study of the intrinsic limitations of the contact resistance of metal/semiconductor interfaces through atomistic simulations Type A1 Journal article
  Year 2018 Publication ECS journal of solid state science and technology Abbreviated Journal Ecs J Solid State Sc  
  Volume 7 Issue 6 Pages N73-N80  
  Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract In this contribution, we report a fundamental study of the factors that set the contact resistivity between metals and highly doped n-type 2D and 3D semiconductors. We investigate the case of n-type doped Si contacted with amorphous TiSi combining first principles calculations with Non-Equilibrium Green functions transport simulations. The evolution of the intrinsic contact resistivity with the doping concentration is found to saturate at similar to 2 x 10(-10) Omega.cm(2) for the case of TiSi and imposes an intrinsic limit to the ultimate contact resistance achievable for n-doped Silamorphous-TiSi (aTiSi). The limit arises from the intrinsic properties of the semiconductors and of the metals such as their electron effective masses and Fermi energies. We illustrate that, in this regime, contacting heavy electron effective mass metals with semiconductor helps reducing the interface intrinsic contact resistivity. This observation seems to hold true regardless of the 3D character of the semiconductor, as illustrated for the case of three 2D semiconducting materials, namely MoS2, ZrS2 and HfS2. (C) The Author(s) 2018. Published by ECS.  
  Address  
  Corporate Author Thesis  
  Publisher Electrochemical society Place of Publication Pennington (N.J.) Editor  
  Language Wos (up) 000440836000004 Publication Date 2018-05-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2162-8769; 2162-8777 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 1.787 Times cited 2 Open Access Not_Open_Access  
  Notes ; The authors thank the imec core CMOS program members, the European Commission, its TAKEMI5 ECSEL research project and the local authorities for their support. ; Approved Most recent IF: 1.787  
  Call Number UA @ lucian @ c:irua:153205UA @ admin @ c:irua:153205 Serial 5130  
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Author Kocabas, T.; Ozden, A.; Demiroglu, I.; Cakir, D.; Sevik, C. doi  openurl
  Title Determination of Dynamically Stable Electrenes toward Ultrafast Charging Battery Applications Type A1 Journal article
  Year 2018 Publication The journal of physical chemistry letters Abbreviated Journal  
  Volume 9 Issue 15 Pages 4267-4274  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Electrenes, an atomically thin form of layered electrides, are very recent members of the 2D materials family. In this work, we employed first principle calculations to determine stable, exfoliatable, and application-promising 2D electrene materials among possible M2X compounds, where M is a group II-A metal and X is a nonmetal element (C, N, P, As, and Sb). The promise of stable electrene compounds for battery applications is assessed via their exfoliation energy, adsorption properties, and migration energy barriers toward relevant Li, Na, K, and Ca atoms. Our calculations revealed five new stable electrene candidates in addition to previously known Ca2N and Sr2N. Among these seven dynamically stable electrenes, Ba2As, Ba2P, Ba2Sb, Ca2N, Sr2N, and Sr2P are found to be very promising for either K or Na ion batteries due to their extremely low migration energy barriers (5-16 meV), which roughly demonstrates 105 times higher mobility than graphene and two to four times higher mobility than other promising 2D materials such as MXene (Mo2C).  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000440956500020 Publication Date 2018-07-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1948-7185 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:193765 Serial 7779  
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Author Siriwardane, E.M.D.; Karki, P.; Sevik, C.; Cakir, D. doi  openurl
  Title Electronic and mechanical properties of stiff rhenium carbide monolayers: A first-principles investigation Type A1 Journal article
  Year 2018 Publication Applied surface science Abbreviated Journal  
  Volume 458 Issue Pages 762-768  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this study, we predicted two new stable metallic Re-C based monolayer structures with a rectangular (r-ReC2) and a hexagonal (h-Re2C) crystal symmetry using first-principle calculations based on density functional theory. Our results obtained from mechanical and phonon calculations and high-temperature molecular dynamic simulations clearly proved the stability of these two-dimensional (2D) crystals. Interestingly, Re-C monolayers in common transition metal carbide structures (i.e. MXenes) were found to be unstable, contrary to expectations. We found that the stable structures, i.e. r-ReC2 and h-Re2C, display superior mechanical properties over the well-known 2D materials. The Young's modulus for r-ReC2 and h-Re2C are extremely high and were calculated as 351 (1310) and 617 (804) N/m (GPa), respectively. Both materials have larger Young's modulus values than the most of the well-known 2D materials. We showed that the combination of the short strong directional p-d bonds, the high coordination number of atoms in the unit-cell and high valence electron density result in strong mechanical properties. Due to its crystal structure, the r-ReC2 monolayer has anisotropic mechanical properties and the crystallographic direction parallel to the C-2 dimers is stiffer compared to perpendicular direction due to strong covalent bonding within C-2 dimers. h-Re2C was derived from the corresponding bulk structure for which we determined the critical thickness for the dynamically stable bulk-derived monolayer structures. In addition, we also investigated the electronic of these two stable structures. Both exhibit metallic behavior and Re-5d orbitals dominate the states around the Fermi level. Due to their ultra high mechanical stability and stiffness, these novel Re-C monolayers can be exploited in various engineering applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000441400000088 Publication Date 2018-07-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0169-4332 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:193776 Serial 7875  
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Author Amini, M.N.; Altantzis, T.; Lobato, I.; Grzelczak, M.; Sánchez-Iglesias, A.; Van Aert, S.; Liz-Marzán, L.M.; Partoens, B.; Bals, S.; Neyts, E.C. url  doi
openurl 
  Title Understanding the Effect of Iodide Ions on the Morphology of Gold Nanorods Type A1 Journal article
  Year 2018 Publication Particle and particle systems characterization Abbreviated Journal Part Part Syst Char  
  Volume 35 Issue 35 Pages 1800051  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)  
  Abstract The presence of iodide ions during the growth of gold nanorods strongly affects the shape of the final products, which is proposed to be due to selective iodide adsorption on certain crystallographic facets. Therefore, a detailed structural and morphological characterization of the starting rods is crucial toward understanding this effect. Electron tomography is used to determine the crystallographic indices of the lateral facets of gold nanorods, as well as those present at the tips. Based on this information, density functional theory calculations are used to determine the surface and interface energies of the observed facets and provide insight into the relationship between the amount of iodide ions in the growth solution and the final morphology of anisotropic gold nanoparticles.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000441893400002 Publication Date 2018-06-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0934-0866 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.474 Times cited 6 Open Access OpenAccess  
  Notes This work was supported by the European Research Council (grant 335078 COLOURATOM to S.B.). T.A., S.V.A. S.B. and E.C.N., acknowledge funding from the Research Foundation Flanders (FWO, Belgium), through project funding (G.0218.14N and G.0369.15N) and a postdoctoral grant to T.A. L.M.L.-M. and M.G. acknowledge funding from the Spanish Ministerio de Economía y Competitividad (grant MAT2013-46101-R). Mozhgan N. Amini and Thomas Altantzis contributed equally to this work. (ROMEO:yellow; preprint:; postprint:restricted ; pdfversion:cannot); ecas_sara Approved Most recent IF: 4.474  
  Call Number EMAT @ emat @c:irua:152998UA @ admin @ c:irua:152998 Serial 5010  
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Author Torun, E.; Sahin, H.; Chaves, A.; Wirtz, L.; Peeters, F.M. url  doi
openurl 
  Title Ab initio and semiempirical modeling of excitons and trions in monolayer TiS3 Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 98 Issue 7 Pages 075419  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We explore the electronic and the optical properties of monolayer TiS3, which shows in-plane anisotropy and is composed of a chain-like structure along one of the lattice directions. Together with its robust direct band gap, which changes very slightly with stacking order and with the thickness of the sample, the anisotropic physical properties of TiS3 make the material very attractive for various device applications. In this study, we present a detailed investigation on the effect of the crystal anisotropy on the excitons and the trions of the TiS3 monolayer. We use many-body perturbation theory to calculate the absorption spectrum of anisotropic TiS3 monolayer by solving the Bethe-Salpeter equation. In parallel, we implement and use a Wannier-Mott model for the excitons that takes into account the anisotropic effective masses and Coulomb screening, which are obtained from ab initio calculations. This model is then extended for the investigation of trion states of monolayer TiS3. Our calculations indicate that the absorption spectrum of monolayer TiS3 drastically depends on the polarization of the incoming light, which excites different excitons with distinct binding energies. In addition, the binding energies of positively and the negatively charged trions are observed to be distinct and they exhibit an anisotropic probability density distribution.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000442342100002 Publication Date 2018-08-21  
  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 10 Open Access  
  Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the FLAG-ERA project TRANS-2D-TMD. H.S. acknowledges financial support from TUBITAK under Project No. 117F095. A.C. acknowledges support from the Brazilian Research Council (CNPq), through the PRONEX/FUNCAP and Science Without Borders programs, and from the Lemann Foundation. E.T. and L.W. acknowledge support from the National Research Fund, Luxembourg (IN-TER/ANR/13/20/NANOTMD). ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:153721UA @ admin @ c:irua:153721 Serial 5076  
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Author Yagmurcukardes, M.; Peeters, F.M.; Sahin, H. url  doi
openurl 
  Title Electronic and vibrational properties of PbI2: From bulk to monolayer Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 98 Issue 8 Pages 085431  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first-principles calculations, we study the dependence of the electronic and vibrational properties of multilayered PbI2 crystals on the number of layers and focus on the electronic-band structure and the Raman spectrum. Electronic-band structure calculations reveal that the direct or indirect semiconducting behavior of PbI2 is strongly influenced by the number of layers. We find that at 3L thickness there is a direct-to-indirect band gap transition (from bulk-to-monolayer). It is shown that in the Raman spectrum two prominent peaks, A(1g) and E-g, exhibit phonon hardening with an increasing number of layers due to the interlayer van der Waals interaction. Moreover, the Raman activity of the A(1g) mode significantly increases with an increasing number of layers due to the enhanced out-of-plane dielectric constant in the few-layer case. We further characterize rigid-layer vibrations of low-frequency interlayer shear (C) and breathing (LB) modes in few-layer PbI2. A reduced monatomic (linear) chain model (LCM) provides a fairly accurate picture of the number of layers dependence of the low-frequency modes and it is shown also to be a powerful tool to study the interlayer coupling strength in layered PbI2.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000442667200008 Publication Date 2018-08-24  
  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 41 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 117F095. Part of this work was supported by FLAG-ERA project TRANS-2D-TMD. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:153716UA @ admin @ c:irua:153716 Serial 5097  
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Author Abdullah, H.M.; Bahlouli, H.; Peeters, F.M.; Van Duppen, B. pdf  doi
openurl 
  Title Confined states in graphene quantum blisters Type A1 Journal article
  Year 2018 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 30 Issue 38 Pages 385301  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Bilayer graphene samples may exhibit regions where the two layers are locally delaminated forming a so-called quanttun blister in the graphene sheet. Electron and hole states can be confined in this graphene quantum blisters (GQB) by applying a global electrostatic bias. We scrutinize the electronic properties of these confined states under the variation of interlayer bias, coupling, and blister's size. The spectra display strong anti-crossings due to the coupling of the confined states on upper and lower layers inside the blister. These spectra are layer localized where the respective confined states reside on either layer or equally distributed. For finite angular momentum, this layer localization can be at the edge of the blister and corresponds to degenerate modes of opposite momenta. Furthermore, the energy levels in GQB exhibit electron-hole symmetry that is sensitive to the electrostatic bias. Finally, we demonstrate that confinement in GQB persists even in the presence of a variation in the interlayer coupling.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication London Editor  
  Language Wos (up) 000443135000001 Publication Date 2018-08-13  
  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 6 Open Access  
  Notes ; HMA and HB acknowledge the Saudi Center for Theoretical Physics (SCTP) for their generous support and the support of KFUPM under physics research group projects RG1502-1 and RG1502-2. This work is supported by the Flemish Science Foundation (FWO-Vl) by a post-doctoral fellowship (BVD). ; Approved Most recent IF: 2.649  
  Call Number UA @ lucian @ c:irua:153620UA @ admin @ c:irua:153620 Serial 5086  
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Author Mulkers, J.; Hals, K.M.D.; Leliaert, J.; Milošević, M.V.; Van Waeyenberge, B.; Everschor-Sitte, K. url  doi
openurl 
  Title Effect of boundary-induced chirality on magnetic textures in thin films Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 98 Issue 6 Pages 064429  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In the quest for miniaturizing magnetic devices, the effects of boundaries and surfaces become increasingly important. Here we show how the recently predicted boundary-induced Dzyaloshinskii-Moriya interaction (DMI) affects the magnetization of ferromagnetic films with a C-infinity v symmetry and a perpendicular magnetic anisotropy. For an otherwise uniformly magnetized film, we find a surface twist when the magnetization in the bulk is canted by an in-plane external field. This twist at the surfaces caused by the boundary-induced DMI differs from the common canting caused by internal DMI observed at the edges of a chiral magnet. Furthermore, we find that the surface twist due to the boundary-induced DMI strongly affects the width of the domain wall at the surfaces. We also find that the skyrmion radius increases in the depth of the film, with the average size of the skyrmion increasing with boundary-induced DMI. This increase suggests that the boundary-induced DMI contributes to the stability of the skyrmion.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000443394600004 Publication Date 2018-08-31  
  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 9 Open Access  
  Notes ; The authors thank Matthias Sitte and Andre Thiaville for fruitful discussions. This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vlaanderen) through Project No. G098917N and the German Research Foundation (DFG) under the Project No. EV 196/2-1. J.L. is supported by the Ghent University Special Research Fund with a BOF postdoctoral fellowship. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:153706UA @ admin @ c:irua:153706 Serial 5093  
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Author Van der Donck, M.; Peeters, F.M. url  doi
openurl 
  Title Interlayer excitons in transition metal dichalcogenide heterostructures Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 98 Issue 11 Pages 115104  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Starting from the single-particle Dirac Hamiltonian for charge carriers in monolayer transition metal dichalcogenides (TMDs), we construct a four-band Hamiltonian describing interlayer excitons consisting of an electron in one TMD layer and a hole in the other TMD layer. An expression for the electron-hole interaction potential is derived, taking into account the effect of the dielectric environment above, below, and between the two TMD layers as well as polarization effects in the transition metal layer and in the chalcogen layers of the TMD layers. We calculate the interlayer exciton binding energy and average in-plane interparticle distance for different TMD heterostructures. The effect of different dielectric environments on the exciton binding energy is investigated and a remarkable dependence on the dielectric constant of the barrier between the two layers is found, resulting from competing effects as a function of the in-plane and out-of-plane dielectric constants of the barrier. The polarization effects in the chalcogen layers, which in general reduce the exciton binding energy, can lead to an increase in binding energy in the presence of strong substrate effects by screening the substrate. The excitonic absorbance spectrum is calculated and we show that the interlayer exciton peak depends linearly on a perpendicular electric field, which agrees with recent experimental results.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000443671900004 Publication Date 2018-09-04  
  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 41 Open Access  
  Notes ; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD and by the FLAG-ERA project TRANS-2D-TMD. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:153653UA @ admin @ c:irua:153653 Serial 5110  
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Author Van Pottelberge, R.; Zarenia, M.; Peeters, F.M. url  doi
openurl 
  Title Magnetic field dependence of atomic collapse in bilayer graphene Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 98 Issue 11 Pages 115406  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The spectrum of a Coulomb impurity in bilayer graphene is investigated as function of the strength of a perpendicular magnetic field for different values of the angular quantum number m and for different values of the gate voltage. We point out fundamental differences between the results from the two-band and four-band model. The supercritical instability and fall-to-center phenomena are investigated in the presence of a magnetic field. We find that in the four-band model the fall-to-center phenomenon occurs as in monolayer graphene, while this is not the case in the two-band model. We find that in a magnetic field the supercritical instability manifests itself as a series of anticrossings in the hole part of the spectrum for states coming from the low-energy band. However, we also find very distinct anticrossings in the electron part of the spectrum that continue into the hole part, which are related to the higher energy band of the four-band model. At these anticrossings, we find a very sharp peak in the probability density close to the impurity, reminiscent for the fall-to-center phenomenon. In this paper, these peculiar and interesting effects are studied for different magnetic field, interlayer coupling, and bias potential strengths.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000443671900010 Publication Date 2018-09-04  
  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 ; We thank Matthias Van der Donck and Ben Van Duppen for fruitful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem funding of the Flemish Government. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:153654UA @ admin @ c:irua:153654 Serial 5113  
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Author Nakhaee, M.; Ketabi, S.A.; Peeters, F.M. url  doi
openurl 
  Title Dirac nodal line in bilayer borophene : tight-binding model and low-energy effective Hamiltonian Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 98 Issue 11 Pages 115413  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Bilayer hexagonal borophene, which is bound together through pillars, is a novel topological semimetal. Using density functional theory, we investigate its electronic band structure and show that it is a Dirac material which exhibits a nodal line. A tight-binding model was constructed based on the Slater-Koster approach, which accurately models the electronic spectrum. We constructed an effective four-band model Hamiltonian to describe the spectrum near the nodal line. This Hamiltonian can be used as a new platform to study the new properties of nodal line semimetals. We found that the nodal line is created by edge states and is very robust against perturbations and impurities. Breaking symmetries can split the nodal line, but cannot open a gap.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000443916200007 Publication Date 2018-09-06  
  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 19 Open Access  
  Notes ; This work was supported by the Methusalem program of the Flemish government and the graphene FLAG-ERA project TRANS-2D-TMD. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:153649UA @ admin @ c:irua:153649 Serial 5090  
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Author Kandemir, A.; Peeters, F.M.; Sahin, H. pdf  doi
openurl 
  Title Monitoring the effect of asymmetrical vertical strain on Janus single layers of MoSSe via spectrum Type A1 Journal article
  Year 2018 Publication The journal of chemical physics Abbreviated Journal J Chem Phys  
  Volume 149 Issue 8 Pages 084707  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using first principles calculations, we study the structural and phononic properties of the recently synthesized Janus type single layers of molybdenum dichalcogenides. The Janus MoSSe single layer possesses 2H crystal structure with two different chalcogenide sides that lead to out-of-plane anisotropy. By virtue of the asymmetric structure of the ultra-thin Janus type crystal, we induced the out-of-plane anisotropy to show the distinctive vertical pressure effect on the vibrational properties of the Janus material. It is proposed that for the corresponding Raman active optical mode of the Janus structure, the phase modulation and the magnitude ratio of the strained atom and its first neighbor atom adjust the distinctive change in the eigen-frequencies and Raman activity. Moreover, a strong variation in the Raman activity of the Janus structure is obtained under bivertical and univertical strains. Not only eigen-frequency shifts but also Raman activities of the optical modes of the Janus structure exhibit distinguishable features. This study reveals that the vertical anisotropic feature of the Janus structure under Raman measurement allows us to distinguish which side of the Janus crystal interacts with the externals (substrate, functional adlayers, or dopants). Published by AIP Publishing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication New York, N.Y. Editor  
  Language Wos (up) 000444035800044 Publication Date 2018-08-30  
  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 ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges financial support from TUBITAK under Project No. 117F095. F.M.P. was supported by the FLAG-ERA-TRANS<INF>2D</INF>TMD. ; Approved Most recent IF: 2.965  
  Call Number UA @ lucian @ c:irua:153711UA @ admin @ c:irua:153711 Serial 5115  
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Author Dong, H.M.; Xu, W.; Peeters, F.M. url  doi
openurl 
  Title Electrical generation of terahertz blackbody radiation from graphene Type A1 Journal article
  Year 2018 Publication Optics express Abbreviated Journal Opt Express  
  Volume 26 Issue 19 Pages 24621-24626  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Recent experimental work on the application of graphene for novel illumination motivated us to present a theoretical study of the blackbody radiation emission from a freely suspended graphene driven by a dc electric field. Strong terahertz (THz) emission, with intensity up to mW/cm(2), can be generated with increasing electric field strength due to the heating of electrons in graphene. We show that the intensity of the THz emission generated electrically from graphene depends rather sensitively on the lattice temperature in relatively weak electric fields, whereas it is less sensitive to the lattice temperature in relative strong electric fields. Our study highlights the practical application of graphene as intense THz source where the radiation is generated electrically. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000444705000026 Publication Date 2018-09-05  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1094-4087 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 3.307 Times cited 14 Open Access  
  Notes ; National Natural Science Foundation of China (NSFC) (11604380, 11574319); Center of Science and Technology of Hefei Academy of Science (2016FXZY002); Department of Science and Technology of Yunnan Province (2016FC001). ; Approved Most recent IF: 3.307  
  Call Number UA @ lucian @ c:irua:153632UA @ admin @ c:irua:153632 Serial 5095  
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Author Bizindavyi, J.; Verhulst, A.S.; Sorée, B.; Groeseneken, G. doi  openurl
  Title Impact of calibrated band-tails on the subthreshold swing of pocketed TFETs Type P1 Proceeding
  Year 2018 Publication Conference digest T2 – 76th Device Research Conference (DRC), JUN 24-27, 2018, Santa Barbara, CA Abbreviated Journal  
  Volume Issue Pages  
  Keywords P1 Proceeding; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000444728400086 Publication Date 2018-09-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 978-1-5386-3028-0 ISBN Additional Links UA library record; WoS full record  
  Impact Factor Times cited Open Access  
  Notes Approved Most recent IF: NA  
  Call Number UA @ admin @ c:irua:153780 Serial 5217  
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Author Van der Donck, M.; Peeters, F.M. url  doi
openurl 
  Title Rich many-body phase diagram of electrons and holes in doped monolayer transition metal dichalcogenides Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 98 Issue 11 Pages 115432  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We use a variational technique to study the many-body phase diagram of electrons and holes in n-doped and p-doped monolayer transition metal dichalcogenides (TMDs). We find a total of four different phases. (i) A fully spin polarized and valley polarized ferromagnetic state. (ii) A state with no global spin polarization but with spin polarization in each valley separately, i.e., spin-valley locking. (iii) A state with spin polarization in one of the valleys and little to no spin polarization in the other valley. (iv) A paramagnetic state with no valley polarization. These phases are separated by first-order phase transitions and are determined by the particle density and the dielectric constant of the substrate. We find that in the presence of a perpendicular magnetic field the four different phases persist. In the case of n-doped MoS2, a fifth phase, which is completely valley polarized but not spin polarized, appears for magnetic fields larger than 7 T and for magnetic fields larger than 23 T completely replaces the second phase.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000445507000009 Publication Date 2018-09-24  
  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 ; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD and by the FLAG-ERA project TRANS-2D-TMD. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:153622UA @ admin @ c:irua:153622 Serial 5125  
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Author Beckers, A.; Thewissen, M.; Sorée, B. pdf  doi
openurl 
  Title Energy filtering in silicon nanowires and nanosheets using a geometric superlattice and its use for steep-slope transistors Type A1 Journal article
  Year 2018 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 124 Issue 14 Pages 144304  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract This paper investigates energy filtering in silicon nanowires and nanosheets by resonant electron tunneling through a geometric superlattice. A geometric superlattice is any kind of periodic geometric feature along the transport direction of the nanowire or nanosheet. Multivalley quantum-transport simulations are used to demonstrate the manifestation of minibands and minibandgaps in the transmission spectra of such a superlattice. We find that the presence of different valleys in the conduction band of silicon favors a nanowire with a rectangular cross section for effective energy filtering. The obtained energy filter can consequently be used in the source extension of a field-effect transistor to prevent high-energy electrons from contributing to the leakage current. Self-consistent Schrodinger-Poisson simulations in the ballistic limit show minimum subthreshold swings of 6 mV/decade for geometric superlattices with indentations. The obtained theoretical performance metrics for the simulated devices are compared with conventional III-V superlatticeFETs and TunnelFETs. The adaptation of the quantum transmitting boundary method to the finite-element simulation of 3-D structures with anisotropic effective mass is presented in Appendixes A and B. Our results bare relevance in the search for steep-slope transistor alternatives which are compatible with the silicon industry and can overcome the power-consumption bottleneck inherent to standard CMOS technologies. Published by AIP Publishing.  
  Address  
  Corporate Author Thesis  
  Publisher American Institute of Physics Place of Publication New York, N.Y. Editor  
  Language Wos (up) 000447148100011 Publication Date 2018-10-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 3 Open Access  
  Notes ; ; Approved Most recent IF: 2.068  
  Call Number UA @ lucian @ c:irua:154729UA @ admin @ c:irua:154729 Serial 5099  
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Author Van Pottelberge, R.; Van Duppen, B.; Peeters, F.M. url  doi
openurl 
  Title Electrical dipole on gapped graphene : bound states and atomic collapse Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 98 Issue 16 Pages 165420  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We investigate the energy spectrum, wave functions, and local density of states of an electrical dipole placed on a sheet of gapped graphene as function of the charge strength Z alpha for different sizes of the dipole and for different regularization parameters. The dipole is modeled as consisting of a positive and negative charge. Bound states are found within the gap region with some energy levels that anticross and others that cross as function of the impurity strength Z alpha. The anticrossings are more pronounced and move to higher charges Z alpha when the length of the dipole decreases. These energy levels turn into atomic collapse states when they enter the positive (or negative) energy continuum. A smooth transition from the single-impurity behavior to the dipole one is observed: The states diving towards the continuum in the single-impurity case are gradually replaced by a series of anticrossings that represent a continuation of the diving states in the single-impurity case. By studying the local density of states at the edge of the dipole we show how the series of anticrossings persist in the positive and negative continuum.  
  Address  
  Corporate Author Thesis  
  Publisher American Physical Society Place of Publication New York, N.Y Editor  
  Language Wos (up) 000447302700010 Publication Date 2018-10-23  
  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 thank Matthias Van der Donck for fruitful discussions. This work was supported by the Research Foundation of Flanders (FWO-V1) through an aspirant research grant for R.V.P. and a postdoctoral grant for B.V.D. ; Approved Most recent IF: 3.836  
  Call Number UA @ lucian @ c:irua:154728UA @ admin @ c:irua:154728 Serial 5094  
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Author Leliaert, J.; Gypens, P.; Milošević, M.V.; Van Waeyenberge, B.; Mulkers, J. pdf  url
doi  openurl
  Title Coupling of the skyrmion velocity to its breathing mode in periodically notched nanotracks Type A1 Journal article
  Year 2019 Publication Journal of physics: D: applied physics Abbreviated Journal J Phys D Appl Phys  
  Volume 52 Issue 2 Pages 024003  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract A thorough understanding of the skyrmion motion through nanotracks is a prerequisite to realize the full potential of spintronic applications like the skyrmion racetrack memory. One of the challenges is to place the data, i.e. skyrmions, on discrete fixed positions, e.g. below a read or write head. In the domain-wall racetrack memory, one proposed solution to this problem was patterning the nanotrack with notches. Following this approach, this paper reports on the skyrmion mobility through a nanotrack with periodic notches (constrictions) made using variations in the chiral Dzyaloshinskii-Moriya interaction. We observe that such notches induce a coupling between the mobility and the skyrmion breathing mode, which manifests itself as velocity-dependent oscillations of the skyrmion diameter and plateaus in which the velocity is independent of the driving force. Despite the fact that domain walls are far more rigid objects than skyrmions, we were able to perform an analogous study and, surprisingly, found even larger plateaus of constant velocity. For both systems it is straightforward to tune the velocity at these plateaus by changing the design of the notched nanotrack geometry, e.g. by varying the distance between the notches. Therefore, the notch-induced coupling between the excited modes and the mobility could offer a strategy to stabilize the velocity against unwanted perturbations in racetrack-like applications. In the last part of the paper we focus on the low-current mobility regimes, whose very rich dynamics at nonzero temperatures are very similar to the operating principle of recently developed probabilistic logic devices. This proves that the mobility of nanomagnetic structures through a periodically modulated track is not only interesting from a fundamental point of view, but has a future in many spintronic applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000449169100001 Publication Date 2018-10-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-3727 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.588 Times cited 10 Open Access  
  Notes ; This work is supported by Fonds Wetenschappelijk Onderzoek (FWO-Vlaanderen) through Project No. G098917N. JL acknowledges his postdoctoral fellowships by the Ghent University special research fund (BOF) and FWO-Vlaanderen. The authors gratefully acknowledge the support of NVIDIA Corporation through donation of Titan Xp and Titan V GPU cards used for this research. ; Approved Most recent IF: 2.588  
  Call Number UA @ admin @ c:irua:155359 Serial 5202  
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Author Li, L.; Kong, X.; Peeters, F.M. pdf  doi
openurl 
  Title New nanoporous graphyne monolayer as nodal line semimetal : double Dirac points with an ultrahigh Fermi velocity Type A1 Journal article
  Year 2019 Publication Carbon Abbreviated Journal Carbon  
  Volume 141 Issue 141 Pages 712-718  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Two-dimensional (2D) carbon materials play an important role in nanomaterials. We propose a new carbon monolayer, named hexagonal-4,4,4-graphyne (H-4,H-4,H-4-graphyne), which is a nanoporous structure composed of rectangular carbon rings and triple bonds of carbon. Using first-principles calculations, we systematically studied the structure, stability, and band structure of this new material. We found that its total energy is lower than that of experimentally synthesized beta-graphdiyne and it is stable at least up to 1500 K. In contrast to the single Dirac point band structure of other 2D carbon monolayers, the band structure of H-4,H-4,H-4-graphyne exhibits double Dirac points along the high-symmetry points and the corresponding Fermi velocities (1.04-1.27 x 10(6) m/s) are asymmetric and higher than that of graphene. The origin of these double Dirac points is traced back to the nodal line states, which can be well explained by a tight-binding model. The H-4,H-4,H-4-graphyne forms a moire superstructure when placed on top of a hexagonal boron nitride substrate. These properties make H-4,H-4,H-4-graphyne a promising semimetal material for applications in high-speed electronic devices. (C) 2018 Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000450312600072 Publication Date 2018-10-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 6.337 Times cited 38 Open Access  
  Notes ; This work was supported by the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl), and the FLAG-ERA project TRANS2DTMD. 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. ; Approved Most recent IF: 6.337  
  Call Number UA @ admin @ c:irua:155364 Serial 5222  
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Author Verreck, D.; Verhulst, A.S.; Van de Put, M.L.; Sorée, B.; Magnus, W.; Collaert, N.; Mocuta, A.; Groeseneken, G. pdf  doi
openurl 
  Title Self-consistent procedure including envelope function normalization for full-zone Schrodinger-Poisson problems with transmitting boundary conditions Type A1 Journal article
  Year 2018 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 124 Issue 20 Pages 204501  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In the quantum mechanical simulation of exploratory semiconductor devices, continuum methods based on a k.p/envelope function model have the potential to significantly reduce the computational burden compared to prevalent atomistic methods. However, full-zone k.p/envelope function simulation approaches are scarce and existing implementations are not self-consistent with the calculation of the electrostatic potential due to the lack of a stable procedure and a proper normalization of the multi-band envelope functions. Here, we therefore present a self-consistent procedure based on a full-zone spectral k.p/envelope function band structure model. First, we develop a proper normalization for the multi-band envelope functions in the presence of transmitting boundary conditions. This enables the calculation of the free carrier densities. Next, we construct a procedure to obtain self-consistency of the carrier densities with the electrostatic potential. This procedure is stabilized with an adaptive scheme that relies on the solution of Poisson's equation in the Gummel form, combined with successive underrelaxation. Finally, we apply our procedure to homostructure In0.53Ga0.47As tunnel field-effect transistors (TFETs) and staggered heterostructure GaAs0.5Sb0.5/In0.53Ga0.47As TFETs and show the importance of self-consistency on the device predictions for scaled dimensions. Published by AIP Publishing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000451743900015 Publication Date 2018-11-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 1 Open Access  
  Notes ; This work was supported by imec's Industrial Affiliation Program. ; Approved Most recent IF: 2.068  
  Call Number UA @ admin @ c:irua:156291 Serial 5228  
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Author Van der Donck, M.; Peeters, F.M. url  doi
openurl 
  Title Excitonic complexes in anisotropic atomically thin two-dimensional materials : black phosphorus and TiS3 Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 98 Issue 23 Pages 235401  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The effect of anisotropy in the energy spectrum on the binding energy and structural properties of excitons, trions, and biexcitons is investigated. To this end we employ the stochastic variational method with a correlated Gaussian basis. We present results for the binding energy of different excitonic complexes in black phosphorus (bP) and TiS3 and compare them with recent results in the literature when available, for which we find good agreement. The binding energies of excitonic complexes in bP are larger than those in TiS3. We calculate the different average interparticle distances in bP and TiS3 and show that excitonic complexes in bP are strongly anisotropic whereas in TiS3 they are almost isotropic, even though the constituent particles have an anisotropic energy spectrum. This is also confirmed by the correlation functions.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000452003400009 Publication Date 2018-12-03  
  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 ; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD and by the FLAG-ERA project TRANS-2D-TMD. ; Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:156247 Serial 5211  
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Author Saberi-Pouya, S.; Zarenia, M.; Vazifehshenas, T.; Peeters, F.M. url  doi
openurl 
  Title Anisotropic charge density wave in electron-hole double monolayers : applied to phosphorene Type A1 Journal article
  Year 2018 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 98 Issue 24 Pages 245115  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The possibility of an inhomogeneous charge density wave phase is investigated in a system of two coupled electron and hole monolayers separated by a hexagonal boron nitride insulating layer. The charge-density-wave state is induced through the assumption of negative compressibility of electron/hole gases in a Coulomb drag configuration between the electron and hole sheets. Under equilibrium conditions, we derive analytical expressions for the density oscillation along the zigzag and armchair directions. We find that the density modulation not only depends on the sign of the compressibility but also on the anisotropy of the low-energy bands. Our results are applicable to any two-dimensional system with anisotropic parabolic bands, characterized by different effective masses. For equal effective masses, i.e., isotropic energy bands, our results agree with Hroblak et al. [Phys. Rev. B 96, 075422 (2017)]. Our numerical results are applied to phosphorene.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000452995600001 Publication Date 2018-12-12  
  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  
  Impact Factor 3.836 Times cited Open Access  
  Notes ; This work was partially supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program of the Flemish government and Iran Science Elites Federation. ; Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:156233 Serial 5195  
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Author Badalov, S.V.; Yagmurcukardes, M.; Peeters, F.M.; Sahin, H. url  doi
openurl 
  Title Enhanced stability of single-layer w-Gallenene through hydrogenation Type A1 Journal article
  Year 2018 Publication The journal of physical chemistry: C : nanomaterials and interfaces Abbreviated Journal J Phys Chem C  
  Volume 122 Issue 49 Pages 28302-28309  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Using density functional theory based first-principles calculations, the effect of surface hydrogenation on the structural, dynamical, electronic, and mechanical properties of monolayer washboard-gallenene (w-gallenene) is investigated. It is found that the dynamically stabilized strained monolayer of w-gallenene has a metallic nonmagnetic ground state. Both one-sided and two-sided hydrogenations of w-gallenene suppress its dynamical instability even when unstrained. Unlike one-sided hydrogenated monolayer w-gallenene (os-w-gallenene), two-sided hydrogenated monolayer w-gallenene (ts-w-gallenene) possesses the same crystal structure as w-gallenene. Electronic band structure calculations reveal that monolayers of hydrogenated derivatives of w-gallenene exhibit also metallic nonmagnetic ground state. Moreover, the linear-elastic constants, in-plane stiffness and Poisson ratio, are enhanced by hydrogenation, which is opposite to the behavior of other hydrogenated monolayer crystals. Furthermore, monolayer w-gallenene and ts-w-gallenene remain dynamically stable up to relatively higher biaxial strains as compared to borophene. With its enhanced dynamical stability, robust metallic character, and enhanced linear-elastic properties, hydrogenated monolayer w-gallenene is a potential candidate for nanodevice applications as a two-dimensional flexible metal.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000453488300053 Publication Date 2018-11-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-7447; 1932-7455 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 4.536 Times cited 20 Open Access  
  Notes ; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges support from Turkish Academy of Sciences under the GEBIP program. This work was supported by FLAG-ERA project TRANS-2D-TMD. This work is supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship (M.Y.). ; Approved Most recent IF: 4.536  
  Call Number UA @ admin @ c:irua:156229 Serial 5210  
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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 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 (up) 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 Li, L.L.; Partoens, B.; Xu, W.; Peeters, F.M. pdf  url
doi  openurl
  Title Electric-field modulation of linear dichroism and Faraday rotation in few-layer phosphorene Type A1 Journal article
  Year 2019 Publication 2D materials Abbreviated Journal 2D Mater  
  Volume 6 Issue 1 Pages 015032  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Electro-optical modulators, which use an electric voltage (or an electric field) to modulate a beam of light, are essential elements in present-day telecommunication devices. Using a self-consistent tight-binding approach combined with the standard Kubo formula, we show that the optical conductivity and the linear dichroism of few-layer phosphorene can be modulated by a perpendicular electric field. We find that the field-induced charge screening plays a significant role in modulating the optical conductivity and the linear dichroism. Distinct absorption peaks are induced in the conductivity spectrum due to the strong quantum confinement along the out-of-plane direction and to the field-induced forbidden-to-allowed transitions. The field modulation of the linear dichroism becomes more pronounced with increasing number of phosphorene layers. We also show that the Faraday rotation is present in few-layer phosphorene even in the absence of an external magnetic field. This optical Hall effect is induced by the reduced lattice symmetry of few-layer phosphorene. The Faraday rotation is greatly influenced by the field-induced charge screening and is strongly dependent on the strength of perpendicular electric field and on the number of phosphorene layers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000454321100002 Publication Date 2018-11-28  
  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 19 Open Access  
  Notes ; This work was financially supported by the Flemish Science Foundation (FWO-Vl) and by the FLAG-ERA project TRANS-2D-TMD. ; Approved Most recent IF: 6.937  
  Call Number UA @ admin @ c:irua:156776 Serial 5207  
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Author Rivera-Julio, J.; Gonzalez-Garcia, A.; Gonzalez-Hernandez, R.; Lopez-Perez, W.; Peeters, F.M.; Hernandez-Nieves, A.D. pdf  doi
openurl 
  Title Vibrational properties of germanane and fluorinated germanene in the chair, boat, and zigzag-line configurations Type A1 Journal article
  Year 2019 Publication Journal of physics : condensed matter Abbreviated Journal J Phys-Condens Mat  
  Volume 31 Issue 7 Pages 075301  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The electronic and vibrational properties of germanane and fluorinated germanene are studied within density functional theory (DFT) and density functional perturbation theory frameworks. Different structural configurations of germanane and fluorinated germanene are investigated. The energy difference between the different configurations are consistently smaller than the energy of thermal fluctuations for all the analyzed DFT functionals LDA, GGA, and hybrid functionals, which implies that, in principle, it is possible to find these different configurations in different regions of the sample as minority phases or local defects. We calculate the Raman and infrared spectra for these configurations by using ab initio calculations and compare it with available experimental spectra for germanane. Our results show the presence of minority phases compatible with the configurations analyzed in this work. As these low energy configurations are metastable the present work shows that the synthesis of these energy competing phases is feasible by selectively changing the synthesis conditions, which is an opportunity to expand in this way the availability of new two-dimensional compounds.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000454925400001 Publication Date 2018-11-27  
  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 8 Open Access  
  Notes ; We acknowledge financial support from PICT-2016-1087 from ANPCyT, PIP 2014-2016 00402 from CONICET and the Argentina-Belgium colaboration program SECYT-FWO FW/ 14/04. This work was also supported by Universidad del Norte and Colciencias (Administrative Department of Science, Technology and Research of Colombia) under Convocatoria 712-Convocatoria para proyectos de investigacion en ciencias basicas ano 2015, Cod: 121571250192, Contrato 110-216. ; Approved Most recent IF: 2.649  
  Call Number UA @ admin @ c:irua:156708 Serial 5238  
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Author Dharma-Wardana, M.W.C.; Neilson, D.; Peeters, F.M. url  doi
openurl 
  Title Correlation functions in electron-electron and electron-hole double quantum wells : temperature, density, and barrier-width dependence Type A1 Journal article
  Year 2019 Publication Physical review B Abbreviated Journal Phys Rev B  
  Volume 99 Issue 3 Pages 035303  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract The classical-map hypernetted-chain (CHNC) scheme, developed for treating fermion fluids at strong coupling and at finite temperatures, is applied to electron-electron and electron-hole double quantum wells. The pair-distribution functions and the local field factors needed in linear-response theory are determined for a range of temperatures, carrier densities, and barrier widths typical for experimental double-quantum-well systems in GaAs-GaAlAs. For electron-hole double quantum wells, a large enhancement in the pair-distribution functions is found for small carrier separations. The CHNC equations for electron-hole systems no longer hold at low densities where bound-state formation occurs.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000455163800004 Publication Date 2019-01-08  
  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 partially supported by the Flemish Science Foundation (FWO-Vl). M.W.C.D.-W. acknowledges with thanks the hospitality and stimulating atmosphere of the Condensed Matter Theory group at the University of Antwerp. ; Approved Most recent IF: 3.836  
  Call Number UA @ admin @ c:irua:156734 Serial 5201  
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Author Mohammed, M.; Verhulst, A.S.; Verreck, D.; Van de Put, M.L.; Magnus, W.; Sorée, B.; Groeseneken, G. pdf  doi
openurl 
  Title Phonon-assisted tunneling in direct-bandgap semiconductors Type A1 Journal article
  Year 2019 Publication Journal of applied physics Abbreviated Journal J Appl Phys  
  Volume 125 Issue 1 Pages 015701  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In tunnel field-effect transistors, trap-assisted tunneling (TAT) is one of the probable causes for degraded subthreshold swing. The accurate quantum-mechanical (QM) assessment of TAT currents also requires a QM treatment of phonon-assisted tunneling (PAT) currents. Therefore, we present a multi-band PAT current formalism within the framework of the quantum transmitting boundary method. An envelope function approximation is used to construct the electron-phonon coupling terms corresponding to local Frohlich-based phonon-assisted inter-band tunneling in direct-bandgap III-V semiconductors. The PAT current density is studied in up to 100 nm long and 20 nm wide p-n diodes with the 2- and 15-band material description of our formalism. We observe an inefficient electron-phonon coupling across the tunneling junction. We further demonstrate the dependence of PAT currents on the device length, for our non-self-consistent formalism which neglects changes in the electron distribution function caused by the electron-phonon coupling. Finally, we discuss the differences in doping dependence between direct band-to-band tunneling and PAT current. Published under license by AIP Publishing.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000455350200021 Publication Date 2019-01-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor 2.068 Times cited 2 Open Access  
  Notes ; This work was supported by Imec's Industrial Affiliation Program. ; Approved Most recent IF: 2.068  
  Call Number UA @ admin @ c:irua:156735 Serial 5224  
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Author Magnus, W.; Brosens, F. pdf  url
doi  openurl
  Title Occupation numbers in a quantum canonical ensemble : a projection operator approach Type A1 Journal article
  Year 2019 Publication Physica: A : theoretical and statistical physics Abbreviated Journal Physica A  
  Volume 518 Issue 518 Pages 253-264  
  Keywords A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT)  
  Abstract Recently, we have used a projection operator to fix the number of particles in a second quantization approach in order to deal with the canonical ensemble. Having been applied earlier to handle various problems in nuclear physics that involve fixed particle numbers, the projector formalism was extended to grant access as well to quantum-statistical averages in condensed matter physics, such as particle densities and correlation functions. In this light, the occupation numbers of the subsequent single-particle energy eigenstates are key quantities to be examined. The goal of this paper is (1) to provide a sound extension of the projector formalism directly addressing the occupation numbers as well as the chemical potential, and (2) to demonstrate how the emerging problems related to numerical instability for fermions can be resolved to obtain the canonical statistical quantities for both fermions and bosons. (C) 2018 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos (up) 000456359200021 Publication Date 2018-11-28  
  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 @ admin @ c:irua:157468 Serial 5223  
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