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Author Torun, E.; Sahin, H.; Cahangirov, S.; Rubio, A.; Peeters, F.M.
Title Anisotropic electronic, mechanical, and optical properties of monolayer WTe2 Type A1 Journal article
Year 2016 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 119 Issue 7 Pages 074307
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using first-principles calculations, we investigate the electronic, mechanical, and optical properties of monolayer WTe2. Atomic structure and ground state properties of monolayer WTe2 (T-d phase) are anisotropic which are in contrast to similar monolayer crystals of transition metal dichalcogenides, such as MoS2, WS2, MoSe2, WSe2, and MoTe2, which crystallize in the H-phase. We find that the Poisson ratio and the in-plane stiffness is direction dependent due to the symmetry breaking induced by the dimerization of the W atoms along one of the lattice directions of the compound. Since the semimetallic behavior of the T-d phase originates from this W-W interaction (along the a crystallographic direction), tensile strain along the dimer direction leads to a semimetal to semiconductor transition after 1% strain. By solving the Bethe-Salpeter equation on top of single shot G(0)W(0) calculations, we predict that the absorption spectrum of T-d-WTe2 monolayer is strongly direction dependent and tunable by tensile strain. (C) 2016 AIP Publishing LLC.
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Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000375158000022 Publication Date 2016-02-19
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 (up) 2.068 Times cited 62 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-V1) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. was supported by a FWO Pegasus Long Marie Curie Fellowship. S.C. and A.R. acknowledge the financial support from the Marie Curie grant FP7-PEOPLE-2013-IEF Project No. 628876, European Research Council (ERC-2010-AdG-267374), Spanish grant (FIS2013-46159-C3-1-P), Grupos Consolidados (IT578-13), and AFOSR Grant No. FA2386-15-1-0006 AOARD 144088, H2020-NMP-2014 project MOSTOPHOS, GA No. SEP-210187476, and COST Action MP1306 (EUSpec). S.C. acknowledges the support from The Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 115F388. ; Approved Most recent IF: 2.068
Call Number UA @ lucian @ c:irua:144747 Serial 4640
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Author Berdiyorov, G.R.; Mortazavi, B.; Ahzi, S.; Peeters, F.M.; Khraisheh, M.K.
Title Effect of straining graphene on nanopore creation using Si cluster bombardment: A reactive atomistic investigation Type A1 Journal article
Year 2016 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 120 Issue 120 Pages 225108
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Graphene nanosheets have recently received a revival of interest as a new class of ultrathin, high-flux, and energy-efficient sieving membranes because of their unique two-dimensional and atomically thin structure, good flexibility, and outstanding mechanical properties. However, for practical applications of graphene for advanced water purification and desalination technologies, the creation of well controlled, high-density, and subnanometer diameter pores becomes a key factor. Here, we conduct reactive force-field molecular dynamics simulations to study the effect of external strain on nanopore creation in the suspended graphene by bombardment with Si clusters. Depending on the size and energy of the clusters, different kinds of topography were observed in the graphene sheet. In all the considered conditions, tensile strain results in the creation of nanopores with regular shape and smooth edges. On the contrary, compressive strain increases the elastic response of graphene to irradiation that leads to the formation of net-like defective structures with predominantly carbon atom chains. Our findings show the possibility of creating controlled nanopores in strained graphene by bombardment with Si clusters. Published by AIP Publishing.
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Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000391535900022 Publication Date 2016-12-15
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 (up) 2.068 Times cited 10 Open Access
Notes ; ; Approved Most recent IF: 2.068
Call Number UA @ lucian @ c:irua:141451 Serial 4554
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Author Dutta, S.; Sankaran, K.; Moors, K.; Pourtois, G.; Van Elshocht, S.; Bommels, J.; Vandervorst, W.; Tokei, Z.; Adelmann, C.
Title Thickness dependence of the resistivity of platinum-group metal thin films Type A1 Journal article
Year 2017 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 122 Issue 2 Pages 025107
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We report on the thin film resistivity of several platinum-group metals (Ru, Pd, Ir, and Pt). Platinum-group thin films show comparable or lower resistivities than Cu for film thicknesses below about 5 nm due to a weaker thickness dependence of the resistivity. Based on experimentally determined mean linear distances between grain boundaries as well as ab initio calculations of the electron mean free path, the data for Ru, Ir, and Cu were modeled within the semiclassical Mayadas-Shatzkes model [Phys. Rev. B 1, 1382 (1970)] to assess the combined contributions of surface and grain boundary scattering to the resistivity. For Ru, the modeling results indicated that surface scattering was strongly dependent on the surrounding material with nearly specular scattering at interfaces with SiO2 or air but with diffuse scattering at interfaces with TaN. The dependence of the thin film resistivity on the mean free path is also discussed within the Mayadas-Shatzkes model in consideration of the experimental findings. Published by AIP Publishing.
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Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000405663800038 Publication Date 2017-07-11
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 (up) 2.068 Times cited 42 Open Access Not_Open_Access
Notes Approved Most recent IF: 2.068
Call Number UA @ lucian @ c:irua:145213 Serial 4729
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Author Geenen, F.A.; van Stiphout, K.; Nanakoudis, A.; Bals, S.; Vantomme, A.; Jordan-Sweet, J.; Lavoie, C.; Detavernier, C.
Title Controlling the formation and stability of ultra-thin nickel silicides : an alloying strategy for preventing agglomeration Type A1 Journal article
Year 2018 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 123 Issue 123 Pages 075303
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The electrical contact of the source and drain regions in state-of-the-art CMOS transistors is nowadays facilitated through NiSi, which is often alloyed with Pt in order to avoid morphological agglomeration of the silicide film. However, the solid-state reaction between as-deposited Ni and the Si substrate exhibits a peculiar change for as-deposited Ni films thinner than a critical thickness of t(c) = 5 nm. Whereas thicker films form polycrystalline NiSi upon annealing above 450 degrees C, thinner films form epitaxial NiSi2 films that exhibit a high resistance toward agglomeration. For industrial applications, it is therefore of utmost importance to assess the critical thickness with high certainty and find novel methodologies to either increase or decrease its value, depending on the aimed silicide formation. This paper investigates Ni films between 0 and 15 nm initial thickness by use of “thickness gradients,” which provide semi-continuous information on silicide formation and stability as a function of as-deposited layer thickness. The alloying of these Ni layers with 10% Al, Co, Ge, Pd, or Pt renders a significant change in the phase sequence as a function of thickness and dependent on the alloying element. The addition of these ternary impurities therefore changes the critical thickness t(c). The results are discussed in the framework of classical nucleation theory. Published by AIP Publishing.
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Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000425807400018 Publication Date 2018-02-21
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 (up) 2.068 Times cited 23 Open Access OpenAccess
Notes ; The authors acknowledge the FWO Vlaanderen, the Hercules Foundation, and BOF-UGent (GOA 01G01513) for providing financial support for this work. This research used resources of the National Synchrotron Light Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-AC02-98CH10886. ; Approved Most recent IF: 2.068
Call Number UA @ lucian @ c:irua:149912UA @ admin @ c:irua:149912 Serial 4929
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Author Mirzakhani, M.; Zarenia, M.; Peeters, F.M.
Title Edge states in gated bilayer-monolayer graphene ribbons and bilayer domain walls Type A1 Journal article
Year 2018 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 123 Issue 20 Pages 204301
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using the effective continuum model, the electron energy spectrum of gated bilayer graphene with a step-like region of decoupled graphene layers at the edge of the sample is studied. Different types of coupled-decoupled interfaces are considered, i.e., zigzag (ZZ) and armchair junctions, which result in significant different propagating states. Two non-valley-polarized conducting edge states are observed for ZZ type, which are mainly located around the ZZ-ended graphene layers. Additionally, we investigated both BA-BA and BA-AB domain walls in the gated bilayer graphene within the continuum approximation. Unlike the BA-BA domain wall, which exhibits gapped insulating behaviour, the domain walls surrounded by different stackings of bilayer regions feature valley-polarized edge states. Our findings are consistent with other theoretical calculations, such as from the tight-binding model and first-principles calculations, and agree with experimental observations. Published by AIP Publishing.
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Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000433977200017 Publication Date 2018-05-23
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 (up) 2.068 Times cited 3 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO), the BOF-UA (Bijzonder Onderzoeks Fonds), the Methusalem program of the Flemish Government, and Iran Nanotechnology Initiative Council (INIC). ; Approved Most recent IF: 2.068
Call Number UA @ lucian @ c:irua:152044UA @ admin @ c:irua:152044 Serial 5020
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Author de de Meux, A.J.; Pourtois, G.; Genoe, J.; Heremans, P.
Title Effects of hole self-trapping by polarons on transport and negative bias illumination stress in amorphous-IGZO Type A1 Journal article
Year 2018 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 123 Issue 16 Pages 161513
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The effects of hole injection in amorphous indium-gallium-zinc-oxide (a-IGZO) are analyzed by means of first-principles calculations. The injection of holes in the valence band tail states leads to their capture as a polaron, with high self-trapping energies (from 0.44 to 1.15 eV). Once formed, they mediate the formation of peroxides and remain localized close to the hole injection source due to the presence of a large diffusion energy barrier (of at least 0.6 eV). Their diffusion mechanism can be mediated by the presence of hydrogen. The capture of these holes is correlated with the low off-current observed for a-IGZO transistors, as well as with the difficulty to obtain a p-type conductivity. The results further support the formation of peroxides as being the root cause of Negative Bias Illumination Stress (NBIS). The strong self-trapping substantially reduces the injection of holes from the contact and limits the creation of peroxides from a direct hole injection. In the presence of light, the concentration of holes substantially rises and mediates the creation of peroxides, responsible for NBIS. Published by AIP Publishing.
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Corporate Author Thesis
Publisher Amer inst physics Place of Publication Melville Editor
Language Wos 000431147200043 Publication Date 2017-10-19
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 (up) 2.068 Times cited 4 Open Access OpenAccess
Notes Approved Most recent IF: 2.068
Call Number UA @ lucian @ c:irua:151570 Serial 5021
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Author Chen, Q.; Wang, W.; Peeters, F.M.
Title Magneto-polarons in monolayer transition-metal dichalcogenides Type A1 Journal article
Year 2018 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 123 Issue 21 Pages 214303
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Landau levels (LLs) are modified by the Frohlich interaction which we investigate within the improved Wigner-Brillouin theory for energies both below and above the longitudinal-optical-continuum in monolayer MoS2.., WS2, MoSe2, and WSe2. Polaron corrections to the LLs are enhanced in monolayer MoS2 as compared to WS2. A series of levels are found at h omega(LO) + lh omega(c), and in addition, the Frohlich interaction lifts the degeneracy between the levels nh omega(c) and h omega(LO) + lh omega(c) resulting in an anticrossing. The screening effect due to the environment plays an important role in the polaron energy corrections, which are also affected by the effective thickness r(eff) parameter. The polaron anticrossing energy gap E-gap decreases with increasing effective thickness r(eff). Published by AIP Publishing.
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Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000434775500014 Publication Date 2018-06-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979; 1089-7550 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (up) 2.068 Times cited 19 Open Access
Notes ; Q. Chen and W. Wang acknowledge the financial support from the China Scholarship Council (CSC). This work was also supported by Hunan Provincial Natural Science Foundation of China (Grant No. 2015JJ2040), by the Scientific Research Fund of Hunan Provincial Education Department (Grant No. 15A042), and by the National Natural Science Foundation of China (Grant No. 11404214). ; Approved Most recent IF: 2.068
Call Number UA @ lucian @ c:irua:151985UA @ admin @ c:irua:151985 Serial 5031
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Author Saberi-Pouya, S.; Vazifehshenas, T.; Saleh, M.; Farmanbar, M.; Salavati-fard, T.
Title Plasmon modes in monolayer and double-layer black phosphorus under applied uniaxial strain Type A1 Journal article
Year 2018 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 123 Issue 17 Pages 174301
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We study the effects of an applied in-plane uniaxial strain on the plasmon dispersions of monolayer, bilayer, and double-layer black phosphorus structures in the long-wavelength limit within the linear elasticity theory. In the low-energy limit, these effects can be modeled through the change in the curvature of the anisotropic energy band along the armchair and zigzag directions. We derive analytical relations of the plasmon modes under uniaxial strain and show that the direction of the applied strain is important. Moreover, we observe that along the armchair direction, the changes of the plasmon dispersion with strain are different and larger than those along the zigzag direction. Using the analytical relations of two-layer phosphorene systems, we found that the strain-dependent orientation factor of layers could be considered as a means to control the variations of the plasmon energy. Furthermore, our study shows that the plasmonic collective modes are more affected when the strain is applied equally to the layers compared to the case in which the strain is applied asymmetrically to the layers. We also calculate the effect of strain on the drag resistivity in a double-layer black phosphorus structure and obtain that the changes in the plasmonic excitations, due to an applied strain, are mainly responsible for the predicted results. This study can be readily extended to other anisotropic two-dimensional materials. Published by AIP Publishing.
Address
Corporate Author Thesis
Publisher American Institute of Physics Place of Publication New York, N.Y. Editor
Language Wos 000431651600014 Publication Date 2018-05-01
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 (up) 2.068 Times cited 4 Open Access
Notes ; ; Approved Most recent IF: 2.068
Call Number UA @ lucian @ c:irua:151522UA @ admin @ c:irua:151522 Serial 5037
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Author Beckers, A.; Thewissen, M.; Sorée, B.
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 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 (up) 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 Lumbeeck, G.; Idrissi, H.; Amin-Ahmadi, B.; Favache, A.; Delmelle, R.; Samaee, V.; Proost, J.; Pardoen, T.; Schryvers, D.
Title Effect of hydriding induced defects on the small-scale plasticity mechanisms in nanocrystalline palladium thin films Type A1 Journal Article
Year 2018 Publication Journal Of Applied Physics Abbreviated Journal J Appl Phys
Volume 124 Issue 22 Pages 225105
Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
Abstract Nanoindentation tests performed on nanocrystalline palladium films subjected to hydriding/dehydriding cycles demonstrate a significant softening when compared to the as-received material. The origin of this softening is unraveled by combining in situ TEM nanomechanical testing with automated crystal orientation mapping in TEM and high resolution TEM. The softening is attributed to the presence of a high density of stacking faults and of Shockley partial dislocations after hydrogen loading. The hydrogen induced defects affect the elementary plasticity mechanisms and the mechanical response by acting as preferential sites for twinning/detwinning during deformation. These results are analyzed and compared to previous experimental and simulation works in the literature. This study provides new insights into the effect of hydrogen on the atomistic deformation and cracking mechanisms as well as on the mechanical properties of nanocrystalline thin films and membranes.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000453254000025 Publication Date 2018-12-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (up) 2.068 Times cited 2 Open Access Not_Open_Access
Notes This work was supported by the Hercules Foundation under Grant No. AUHA13009, the Flemish Research Fund (FWO) under Grant No. G.0365.15N, and the Flemish Strategic Initiative for Materials (SIM) under the project InterPoCo. Dr. H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). We would like to thank Dr. Hadi Pirgazi from UGent for his technical support to process the ACOM data in the OIM Analysis software. Approved Most recent IF: 2.068
Call Number EMAT @ emat @c:irua:155742 Serial 5135
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Author Mohammed, M.; Verhulst, A.S.; Verreck, D.; Van de Put, M.L.; Magnus, W.; Sorée, B.; Groeseneken, G.
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 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 (up) 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 Verreck, D.; Verhulst, A.S.; Van de Put, M.L.; Sorée, B.; Magnus, W.; Collaert, N.; Mocuta, A.; Groeseneken, G.
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 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 (up) 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 Milovanović, S.P.; Covaci, L.; Peeters, F.M.
Title Strain fields in graphene induced by nanopillar mesh Type A1 Journal article
Year 2019 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 125 Issue 8 Pages 082534
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The mechanical and electronic properties of a graphene membrane placed on top of a triangular superlattice of nanopillars are investigated. We use molecular dynamics simulations to access the deformation fields and the tight-binding approaches to calculate the electronic properties. Ripples form in the graphene layer that span across the unit cell, connecting neighboring pillars, in agreement with recent experiments. We find that the resulting pseudo-magnetic field (PMF) varies strongly across the unit cell. We investigate the dependence of PMF on unit cell boundary conditions, height of the pillars, and the strength of the van der Waals interaction between graphene and the substrate. We find direct correspondence with typical experiments on pillars, showing intrinsic “slack” in the graphene membrane. PMF values are confirmed by the local density of states calculations performed at different positions of the unit cell showing pseudo-Landau levels with varying spacings. Our findings regarding the relaxed membrane configuration and the induced strains are transferable to other flexible 2D membranes.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000460033800038 Publication Date 2019-01-16
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 (up) 2.068 Times cited 5 Open Access
Notes ; S.P.M. is supported by the Flemish Science Foundation (FWO). ; Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:158605 Serial 5231
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Author Gu, J.-G.; Zhang, Y.; Gao, M.-X.; Wang, H.-Y.; Zhang, Q.-Z.; Yi, L.; Jiang, W.
Title Enhancement of surface discharge in catalyst pores in dielectric barrier discharges Type A1 Journal article
Year 2019 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 125 Issue 15 Pages 153303
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The generation of high-density plasmas on the surface of porous catalysts is very important for plasma catalysis, as it determines the active surface of the catalyst that is available for the reaction. In this work, we investigate the mechanism of surface and volume plasma streamer formation and propagation near micro-sized pores in dielectric barrier discharges operating in air at atmospheric pressure. A two-dimensional particle-in-cell/ Monte Carlo collision model is used to model the individual kinetic behavior of plasma species. Our calculations indicate that the surface discharge is enhanced on the surface of the catalyst pores compared with the microdischarge inside the catalyst pores. The reason is that the surface ionization wave induces surface charging along the catalyst pore sidewalls, leading to a strong electric field along the pore sidewalls, which in turn further enhances the surface discharge. Therefore, highly concentrated reactive species occur on the surfaces of the catalyst pores, indicating high-density plasmas on the surface of porous catalysts. Indeed, the maximum electron impact excitation and ionization rates occur on the pore surface, indicating the more pronounced production of excited state and electron-ion pairs on the pore surface than inside the pore, which may profoundly affect the plasma catalytic process. Published under license by AIP Publishing.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000465441200022 Publication Date 2019-04-15
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 (up) 2.068 Times cited 4 Open Access Not_Open_Access
Notes Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:160397 Serial 5273
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Author Vohra, A.; Khanam, A.; Slotte, J.; Makkonen, I.; Pourtois, G.; Loo, R.; Vandervorst, W.
Title Evolution of phosphorus-vacancy clusters in epitaxial germanium Type A1 Journal article
Year 2019 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 125 Issue 2 Pages 025701
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract The E centers (dopant-vacancy pairs) play a significant role in dopant deactivation in semiconductors. In order to gain insight into dopant-defect interactions during epitaxial growth of in situ phosphorus doped Ge, positron annihilation spectroscopy, which is sensitive to open-volume defects, was performed on Ge layers grown by chemical vapor deposition with different concentrations of phosphorus (similar to 1 x 10(18)-1 x 10(20) cm(-3)). Experimental results supported by first-principles calculations based on the two component density-functional theory gave evidence for the existence of mono-vacancies decorated by several phosphorus atoms as the dominant defect type in the epitaxial Ge. The concentration of vacancies increases with the amount of P-doping. The number of P atoms around the vacancy also increases, depending on the P concentration. The evolution of P-n-V clusters in Ge contributes significantly to the dopant deactivation. Published under license by AIP Publishing.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000455922100057 Publication Date 2019-01-08
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 (up) 2.068 Times cited 5 Open Access Not_Open_Access
Notes Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:156722 Serial 5274
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Author Piorra, A.; Hrkac, V.; Wolff, N.; Zamponi, C.; Duppel, V.; Hadermann, J.; Kienle, L.; Quandt, E.
Title (Ba0.85Ca0.15)(Ti0.9Zr0.1)O3 thin films prepared by PLD : relaxor properties and complex microstructure Type A1 Journal article
Year 2019 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 125 Issue 24 Pages 244103
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Ferroelectric lead-free thin films of the composition (Ba0.85Ca0.15)(Ti0.9Zr0.1)O-3 (BCZT) were deposited by pulsed laser deposition on Pt/TiO2/SiO2/Si substrates using a ceramic BCZT target prepared by a conventional solid state reaction. The target material itself shows a piezoelectric coefficient of d(33)=640pm/V. The (111) textured thin films possess a thickness of up to 1.1 mu m and exhibit a clamped piezoelectric response f of up to 190pm/V, a dielectric coefficient of (r)=2000 at room temperature, and a pronounced relaxor behavior. As indicated by transmission electron microscopy, the thin films are composed of longitudinal micrometersized columns with similar to 100nm lateral dimension that are separated at twin- and antiphase boundaries. The superposition phenomena according to this columnar growth were simulated based on suitable supercells. The major structural component is described as a tetragonal distorted variant of the perovskite parent type; however, frequently coherently intergrown nanodomains were observed indicating a much more complex structure that is characterized by a 7-layer modulation along the growth direction of the films.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000474439600002 Publication Date 2019-06-25
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 (up) 2.068 Times cited Open Access
Notes ; The authors want to thank Dr. Martina Luysberg and Dr. Lothar Houben from the Ernst Ruska Centre in Julich for discussion and CS-corrected microscopy. Funding of this work via the DFG (No. CRC1261) “Magnetoelectric Sensors: From Composite Materials to Biomagnetic Diagnostics” and the PAK902 is gratefully acknowledged. ; Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:161310 Serial 5399
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Author Chen, Q.; Li, L.L.; Peeters, F.M.
Title Inner and outer ring states of MoS2 quantum rings : energy spectrum, charge and spin currents Type A1 Journal article
Year 2019 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 125 Issue 24 Pages 244303
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We investigate the energy levels and persistent currents of MoS2 quantum rings having different shapes and edge types in the presence of a perpendicular magnetic field by means of the tight-binding approach. We find states localized at the inner and outer boundaries of the ring. These energy levels exhibit different magnetic field dependences for the inner and outer ring states due to their different localization properties. They both exhibit the usual Aharanov-Bohm oscillations but with different oscillation periods. In the presence of spin-orbit coupling, we show distinct spin and charge persistent currents for inner and outer ring states. We find well-defined spin currents with negligibly small charge currents. This is because the local currents of spin-up and -down states flow in opposite directions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000474439600026 Publication Date 2019-06-25
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 (up) 2.068 Times cited 10 Open Access
Notes ; This work was supported by the Hunan Provincial Natural Science Foundation of China (Nos. 2015JJ2040, 2018JJ2080, and 2018JJ4047), the National Natural Science Foundation of China (NNSFC) (No. 51502087), the Scientific Research Fund of Hunan Provincial Education Department (Nos. 15A042, 15B056, and 17B060), and the Flemish Science Foundation (FWO-VI). ; Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:161309 Serial 5417
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Author Vohra, A.; Khanam, A.; Slotte, J.; Makkonen, I.; Pourtois, G.; Porret, C.; Loo, R.; Vandervorst, W.
Title Heavily phosphorus doped germanium : strong interaction of phosphorus with vacancies and impact of tin alloying on doping activation Type A1 Journal article
Year 2019 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 125 Issue 22 Pages 225703
Keywords A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract We examined the vacancy trapping proficiency of Sn and P atoms in germanium using positron annihilation spectroscopy measurements, sensitive to the open-volume defects. Epitaxial Ge1 xSnx films were grown by chemical vapor deposition with different P concentrations in the 3: 0 1019-1: 5 1020 cm 3 range. We corroborate our findings with first principles simulations. Codoping of Ge with a Sn concentration of up to 9% is not an efficient method to suppress the free vacancy concentration and the formation of larger phosphorus-vacancy complexes. Experimental results confirm an increase in the number of P atoms around the monovacancy with P-doping, leading to dopant deactivation in epitaxial germanium-tin layers with similar Sn content. Vice versa, no impact on the improvement of maximum achieved P activation in Ge with increasing Sn-doping has been observed. Theoretical calculations also confirm that Pn-V (vacancy) complexes are energetically more stable than the corresponding SnmPn-V and Snm-V defect structures with the same number of alien atoms (Sn or P) around the monovacancy. he strong attraction of vacancies to the phosphorus atoms remains the dominant dopant deactivation mechanism in Ge as well as in Ge1 xSnx. Published under license by AIP Publishing.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000471698600044 Publication Date 2019-06-10
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 (up) 2.068 Times cited 1 Open Access
Notes Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:161333 Serial 6300
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Author Bafekry, A.; Shayesteh, S.F.; Ghergherehchi, M.; Peeters, F.M.
Title Tuning the bandgap and introducing magnetism into monolayer BC3 by strain/defect engineering and adatom/molecule adsorption Type A1 Journal article
Year 2019 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 126 Issue 14 Pages 144304
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using first-principles calculations, we study the structural, electronic, and optical properties of pristine BC3. Our results show that BC3 is a semiconductor which can be useful in optoelectronic device applications. Furthermore, we found that the electronic properties of BC3 can be modified by strain and the type of edge states. With increasing thickness, the indirect bandgap decreases from 0.7 eV (monolayer) to 0.27 eV (bulk). Upon uniaxial tensile strain along the armchair and zigzag directions, the bandgap slightly decreases, and with increasing uniaxial strain, the bandgap decreases, and when reaching -8%, a semiconductor-to-metal transition occurs. By contrast, under biaxial strain, the bandgap increases to 1.2 eV in +8% and decreases to zero in -8%. BC3 nanoribbons with different widths exhibit magnetism at the zigzag edges, while, at the armchair edges, they become semiconductor, and the bandgap is in the range of 1.0-1.2 eV. Moreover, we systematically investigated the effects of adatoms/molecule adsorption and defects on the structural, electronic, and magnetic properties of BC3. The adsorption of various adatoms and molecules as well as topological defects (vacancies and Stone-Wales defects) can modify the electronic properties. Using these methods, one can tune BC3 into a metal, half-metal, ferromagnetic-metal, and dilute-magnetic semiconductor or preserve its semiconducting character. Published under license by AIP Publishing.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000503995300019 Publication Date 2019-10-10
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 (up) 2.068 Times cited 48 Open Access
Notes Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:165160 Serial 6328
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Author Bafekry, A.; Shayesteh, S.F.; Peeters, F.M.
Title Two-dimensional carbon nitride (2DCN) nanosheets : tuning of novel electronic and magnetic properties by hydrogenation, atom substitution and defect engineering Type A1 Journal article
Year 2019 Publication Journal of applied physics Abbreviated Journal J Appl Phys
Volume 126 Issue 21 Pages 215104
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract By employing first-principles calculations within the framework of density functional theory, we investigated the structural, electronic, and magnetic properties of graphene and various two-dimensional carbon-nitride (2DNC) nanosheets. The different 2DCN gives rise to diverse electronic properties such as metals (C3N2), semimetals (C4N and C9N4), half-metals (C4N3), ferromagnetic-metals (C9N7), semiconductors (C2N, C3N, C3N4, C6N6, and C6N8), spin-glass semiconductors (C10N9 and C14N12), and insulators (C2N2). Furthermore, the effects of adsorption and substitution of hydrogen atoms as well as N-vacancy defects on the electronic and magnetic properties are systematically studied. The introduction of point defects, including N vacancies, interstitial H impurity into graphene and different 2DCN crystals, results in very different band structures. Defect engineering leads to the discovery of potentially exotic properties that make 2DCN interesting for future investigations and emerging technological applications with precisely tailored properties. These properties can be useful for applications in various fields such as catalysis, energy storage, nanoelectronic devices, spintronics, optoelectronics, and nanosensors. Published under license by AIP Publishing.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000504007300023 Publication Date 2019-12-02
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 (up) 2.068 Times cited 57 Open Access
Notes Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:165733 Serial 6329
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Author Vanraes, P.; Bogaerts, A.
Title The essential role of the plasma sheath in plasma–liquid interaction and its applications—A perspective Type A1 Journal Article
Year 2021 Publication Journal Of Applied Physics Abbreviated Journal J Appl Phys
Volume 129 Issue 22 Pages 220901
Keywords A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
Abstract Based on the current knowledge, a plasma–liquid interface looks and behaves very differently from its counterpart at a solid surface. Local processes characteristic to most liquids include a stronger evaporation, surface deformations, droplet ejection, possibly distinct mechanisms behind secondary electron emission, the formation of an electric double layer, and an ion drift-mediated liquid resistivity. All of them can strongly influence the interfacial charge distribution. Accordingly, the plasma sheath at a liquid surface is most likely unique in its own way, both with respect to its structure and behavior. However, insights into these properties are still rather scarce or uncertain, and more studies are required to further disclose them. In this Perspective, we argue why more research on the plasma sheath is not only recommended but also crucial to an accurate understanding of the plasma–liquid interaction. First, we analyze how the sheath regulates various elementary processes at the plasma–liquid interface, in terms of the electrical coupling, the bidirectional mass transport, and the chemistry between plasma and liquid phase. Next, these three regulatory functions of the sheath are illustrated for concrete applications. Regarding the electrical coupling, a great deal of attention is paid to the penetration of fields into biological systems due to their relevance for plasma medicine, plasma agriculture, and food processing. Furthermore, we illuminate the role of the sheath in nuclear fusion, nanomaterial synthesis, and chemical applications. As such, we hope to motivate the plasma community for more fundamental research on plasma sheaths at liquid surfaces.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000681700000013 Publication Date 2021-06-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (up) 2.068 Times cited Open Access OpenAccess
Notes P.V. thanks Dr. Angela Privat Maldonado (University of Antwerp) for the fruitful discussions on Sec. III and Professor Mark J. Kushner (University of Michigan) for the interesting discussion on Ref. 198. Approved Most recent IF: 2.068
Call Number PLASMANT @ plasmant @c:irua:178814 Serial 6794
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Author Bruggeman, P.J.; Bogaerts, A.; Pouvesle, J.M.; Robert, E.; Szili, E.J.
Title Plasma–liquid interactions Type A1 Journal Article
Year 2021 Publication Journal Of Applied Physics Abbreviated Journal J Appl Phys
Volume 130 Issue 20 Pages 200401
Keywords A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ;
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2021-11-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0021-8979 ISBN Additional Links UA library record
Impact Factor (up) 2.068 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 2.068
Call Number PLASMANT @ plasmant @c:irua:184245 Serial 6830
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Author Milošević, M.V.; Mandrus, D.
Title 2D quantum materials : magnetism and superconductivity Type A1 Journal article
Year 2021 Publication Journal Of Applied Physics Abbreviated Journal J Appl Phys
Volume 130 Issue 18 Pages 180401
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000720289900004 Publication Date 2021-11-11
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
Impact Factor (up) 2.068 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:184090 Serial 6963
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Author Bafekry, A.; Stampfl, C.; Naseri, M.; Fadlallah, M.M.; Faraji, M.; Ghergherehchi, M.; Gogova, D.; Feghhi, S.A.H.
Title Effect of electric field and vertical strain on the electro-optical properties of the MoSi2N4 bilayer : a first-principles calculation Type A1 Journal article
Year 2021 Publication Journal Of Applied Physics Abbreviated Journal J Appl Phys
Volume 129 Issue 15 Pages 155103
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Recently, a two-dimensional (2D) MoSi 2N 4 (MSN) structure has been successfully synthesized [Hong et al., Science 369(6504), 670-674 (2020)]. Motivated by this result, we investigate the structural, electronic, and optical properties of MSN monolayer (MSN-1L) and bilayer (MSN-2L) under the applied electric field (E-field) and strain using density functional theory calculations. We find that the MSN-2L is a semiconductor with an indirect bandgap of 1.60 (1.80)eV using Perdew-Burke-Ernzerhof (HSE06). The bandgap of MSN-2L decreases as the E-field increases from 0.1 to 0.6V/angstrom and for larger E-field up to 1.0V/angstrom the bilayer becomes metallic. As the vertical strain increases, the bandgap decreases; more interestingly, a semiconductor to a metal phase transition is observed at a strain of 12 %. Furthermore, the optical response of the MSN-2L is in the ultraviolet (UV) region of the electromagnetic spectrum. The absorption edge exhibits a blue shift by applying an E-field or a vertical compressive strain. The obtained interesting properties suggest MSN-2L as a promising material in electro-mechanical and UV opto-mechanical devices.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000640620400003 Publication Date 2021-04-15
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 (up) 2.068 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:178233 Serial 6981
Permanent link to this record
 

 
Author Osca, J.; Sorée, B.
Title Torque field and skyrmion motion by spin transfer torque in a quasi-2D interface in presence of strong spin-orbit interaction Type A1 Journal article
Year 2021 Publication Journal Of Applied Physics Abbreviated Journal J Appl Phys
Volume 130 Issue 13 Pages 133903
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We investigate the torque field and skyrmion motion at an interface between a ferromagnet hosting a skyrmion and a material with a strong spin-orbit interaction. We analyze both semiconductor materials and topological insulators using a Hamiltonian model that includes a linear term. The spin torque-inducing current is considered to flow in the single band limit; therefore, a quantum model of current is used. Skyrmion motion due to spin transfer torque proves to be more difficult in the presence of a spin-orbit interaction in the case where only interface in-plane currents are present. However, edge effects in narrow nanowires can be used to drive the skyrmion motion and to exert a limited control on its motion direction. We also show the differences and similarities between torque fields due to electric current in the many and single band limits. Published under an exclusive license by AIP Publishing.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000755090400003 Publication Date 2021-10-07
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 (up) 2.068 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:186452 Serial 7034
Permanent link to this record
 

 
Author Karaaslan, Y.; Haskins, J.B.; Yapicioglu, H.; Sevik, C.
Title Influence of randomly distributed vacancy defects on thermal transport in two-dimensional group-III nitrides Type A1 Journal article
Year 2021 Publication Journal Of Applied Physics Abbreviated Journal J Appl Phys
Volume 129 Issue 22 Pages 224304
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Efficient thermal transport control is a fundamental issue for electronic device applications such as information, communication, and energy storage technologies in modern electronics in order to achieve desired thermal conditions. Structural defects in materials provide a mechanism to adjust the thermal transport properties of these materials on demand. In this context, the effect of structural defects on lattice thermal conductivities of two-dimensional hexagonal binary group-III nitride (XN, X = B, Al, and Ga) semiconductors is systematically investigated by means of classical molecular dynamics simulations performed with recently developed transferable inter-atomic potentials accurately describing defect energies. Here, two different Green-Kubo based approaches and another approach based on non-equilibrium molecular dynamics are compared in order to get an overall understanding. Our investigation clearly shows that defect concentrations of 3% decrease the thermal conductivity of systems containing these nitrites up to 95%. Results hint that structural defects can be used as effective adjustment parameters in controlling thermal transport properties in device applications associated with these materials. Published under an exclusive license by AIP Publishing.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000692024300001 Publication Date 2021-06-09
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 (up) 2.068 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:181618 Serial 8096
Permanent link to this record
 

 
Author Saiz, F.; Karaaslan, Y.; Rurali, R.; Sevik, C.
Title Interatomic potential for predicting the thermal conductivity of zirconium trisulfide monolayers with molecular dynamics Type A1 Journal article
Year 2021 Publication Journal Of Applied Physics Abbreviated Journal J Appl Phys
Volume 129 Issue 15 Pages 155105
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract We present here a new interatomic potential parameter set to predict the thermal conductivity of zirconium trisulfide monolayers. The generated Tersoff-type force field is parameterized using data collected with first-principles calculations. We use non-equilibrium molecular dynamics simulations to predict the thermal conductivity. The generated parameters result in very good agreement in structural, mechanical, and dynamical parameters. The room temperature lattice thermal conductivity ( kappa) of the considered crystal is predicted to be kappa x x = 25.69Wm – 1K – 1 and kappa y y = 42.38Wm – 1K – 1, which both agree well with their corresponding first-principles values with a discrepancy of less than 5%. Moreover, the calculated kappa variation with temperature (200 and 400 K) are comparable within the framework of the accuracy of both first-principles and molecular dynamics simulations.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000641993600001 Publication Date 2021-04-19
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 (up) 2.068 Times cited Open Access OpenAccess
Notes Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:178234 Serial 8112
Permanent link to this record
 

 
Author Sun, J.; Li, Y.; Karaaslan, Y.; Sevik, C.; Chen, Y.
Title Misfit dislocation structure and thermal boundary conductance of GaN/AlN interfaces Type A1 Journal article
Year 2021 Publication Journal Of Applied Physics Abbreviated Journal J Appl Phys
Volume 130 Issue 3 Pages 035301
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The structure and thermal boundary conductance of the wurtzite GaN/AlN (0001) interface are investigated using molecular dynamics simulation. Simulation results with three different empirical interatomic potentials have produced similar misfit dislocation networks and dislocation core structures. Specifically, the misfit dislocation network at the GaN/AlN interface is found to consist of pure edge dislocations with a Burgers vector of 1/3(1 (2) over bar 10) and the misfit dislocation core has an eight-atom ring structure. Although different interatomic potentials lead to different dislocation properties and thermal conductance values, all have demonstrated a significant effect of misfit dislocations on the thermal boundary conductance of the GaN/AlN (0001) interface. Published under an exclusive license by AIP Publishing.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000694725800001 Publication Date 2021-07-15
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 (up) 2.068 Times cited Open Access Not_Open_Access
Notes Approved Most recent IF: 2.068
Call Number UA @ admin @ c:irua:181623 Serial 8254
Permanent link to this record
 

 
Author Thomé, T.; Colaux, J.L.; Colomer, J.-F.; Bertoni, G.; Terwagne, G.
Title Formation of carbon nitride nanospheres by ion implantation Type A1 Journal article
Year 2007 Publication Materials chemistry and physics Abbreviated Journal Mater Chem Phys
Volume 103 Issue 2-3 Pages 290-294
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Carbon nitride nanospheres have been synthesized into copper by simultaneous high fluence (10(18) at. cm(-2)) implantations of C-12 and N-15 ions. The composition of the implanted region has been measured using C-12(d,p(0))C-13 and N-15(d,alpha(0))C-13 nuclear reactions induced by a 1.05 MeV deuteron beam. The C-12 and N-15 depth profiles are very close and the retained doses into copper are relatively high, which indicates that carbon and nitrogen diffusion processes are likely limited during implantation. High resolution transmission electron microscopy (HRTEM) observations and electron diffraction (ED) analyses have been carried out to determine the structure of the nanospheres formed during implantation. Some consist in small hollow amorphous nanocapsules with sizes ranging from 30 to 100 nm. Large gas bubbles with diameters up to 300 mn have also been observed in the copper matrix. Electron energy-loss spectroscopy (EELS) measurements performed on the small nanocapsules indicate that their shells are composed of carbon and nitrogen. (c) 2007 Elsevier B.V. All rights reserved.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000247715300016 Publication Date 2007-02-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0254-0584; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (up) 2.084 Times cited 1 Open Access
Notes Approved Most recent IF: 2.084; 2007 IF: 1.871
Call Number UA @ lucian @ c:irua:102670 Serial 1258
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Author Navío, C.; Vallejos, S.; Stoycheva, T.; Llobet, E.; Correig, X.; Snyders, R.; Blackman, C.; Umek, P.; Ke, X.; Van Tendeloo, G.; Bittencourt, C.;
Title Gold clusters on WO3 nanoneedles grown via AACVD : XPS and TEM studies Type A1 Journal article
Year 2012 Publication Materials chemistry and physics Abbreviated Journal Mater Chem Phys
Volume 134 Issue 2/3 Pages 809-813
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We have prepared tungsten oxide films decorated with gold particles on Si substrates by aerosol assisted chemical vapor deposition (AACVD) and characterized them using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). SEM shows that the films are composed of needle-like structures and TEM shows that both the needles and the gold particles are crystalline. XPS indicates the presence of oxygen vacancies, i.e. the films are WO3−x, and hence the deposited material is composed of semiconducting nanostructures and that the interaction between the gold particles and the WO3 needles surface is weak. The synthesis of semiconducting tungsten oxide nanostructures decorated with metal particles represents an important step towards the development of sensing devices with optimal properties.
Address
Corporate Author Thesis
Publisher Place of Publication Lausanne Editor
Language Wos 000305918200038 Publication Date 2012-04-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0254-0584; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor (up) 2.084 Times cited 52 Open Access
Notes Iap Approved Most recent IF: 2.084; 2012 IF: 2.072
Call Number UA @ lucian @ c:irua:97705 Serial 1356
Permanent link to this record