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Author | Mirzakhani, M.; Peeters, F.M.; Zarenia, M. | ||||
Title | Circular quantum dots in twisted bilayer graphene | Type | A1 Journal article | ||
Year | 2020 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
Volume | 101 | Issue | 7 | Pages | 075413 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Within a tight-binding approach, we investigate the effect of twisting angle on the energy levels of circular bilayer graphene (BLG) quantum dots (QDs) in both the absence and presence of a perpendicular magnetic field. The QDs are defined by an infinite-mass potential, so that the specific edge effects are not present. In the absence of magnetic field (or when the magnetic length is larger than the moire length), we show that the low-energy states in twisted BLG QDs are completely affected by the formation of moire patterns, with a strong localization at AA-stacked regions. When magnetic field increases, the energy gap of an untwisted BLG QD closes with the edge states, localized at the boundaries between the AA- and AB-stacked spots in a twisted BLG QD. Our observation of the spatial localization of the electrons in twisted BLG QDs can be experimentally probed by low-bias scanning tunneling microscopy measurements. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000512772200004 | Publication Date | 2020-02-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.7 | Times cited | 19 | Open Access | |
Notes | ; We gratefully acknowledge discussions with I. Snyman. M.Z. acknowledges support from the U.S. Department of Energy (Office of Science) under Grant No. DE-FG0205ER46203. ; | Approved | Most recent IF: 3.7; 2020 IF: 3.836 | ||
Call Number | UA @ admin @ c:irua:166493 | Serial | 6470 | ||
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Author | Nguyen, H.T.T.; Obeid, M.M.; Bafekry, A.; Idrees, M.; Vu, T.V.; Phuc, H., V; Hieu, N.N.; Le Hoa, T.; Amin, B.; Nguyen, C., V | ||||
Title | Interfacial characteristics, Schottky contact, and optical performance of a graphene/Ga2SSe van der Waals heterostructure: Strain engineering and electric field tunability | Type | A1 Journal article | ||
Year | 2020 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
Volume | 102 | Issue | 7 | Pages | 075414-10 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Two-dimensional graphene-based van der Waals heterostructures have received considerable interest because of their intriguing characteristics compared with the constituent single-layer two-dimensional materials. Here, we investigate the interfacial characteristics, Schottky contact, and optical performance of graphene/Ga2SSe van der Waals (vdW) heterostructure using first-principles calculations. The effects of stacking patterns, electric gating, and interlayer coupling on the interfacial properties of graphene/Ga2SSe heterostructures are also examined. Our results demonstrate that the Dirac cone of graphene is well preserved at the F point in all stacking patterns due to the weak vdW interactions, which keep the heterostructures feasible such that they can be obtained in further experiments. Moreover, depending on the stacking patterns, a small band gap of about 13-17 meV opens in graphene and has a high carrier mobility, indicating that the graphene/Ga2SSe heterostructures are potential candidates for future high-speed nanoelectronic applications. In the ground state, the graphene/Ga2SSe heterostructures form an n-type Schottky contact. The transformation from an n-type to a p-type Schottky contact or to an Ohmic contact can be forced by electric gating or by varying the interlayer coupling. Our findings could provide physical guidance for designing controllable Schottky nanodevices with high electronic and optical performances. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000557294500006 | Publication Date | 2020-08-07 | |
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 | 3.7 | Times cited | 12 | Open Access | |
Notes | ; This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under Grant No. 103.01-2019.05. The authors declare that there are no conflicts of interest regarding the publication of this paper. ; | Approved | Most recent IF: 3.7; 2020 IF: 3.836 | ||
Call Number | UA @ admin @ c:irua:171163 | Serial | 6549 | ||
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Author | Ahmadkhani, S.; Alihosseini, M.; Ghasemi, S.; Ahmadabadi, I.; Hassani, N.; Peeters, F.M.; Neek-Amal, M. | ||||
Title | Multiband flattening and linear Dirac band structure in graphene with impurities | Type | A1 Journal article | ||
Year | 2023 | Publication | Physical review B | Abbreviated Journal | |
Volume | 107 | Issue | 7 | Pages | 075401-75408 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Flat bands in the energy spectrum have attracted a lot of attention in recent years because of their unique properties and promising applications. Special arrangement of impurities on monolayer graphene are proposed to generate multiflat bands in the electronic band structure. In addition to the single midgap states in the spectrum of graphene with low hydrogen density, we found closely spaced bands around the Fermi level with increasing impurity density, which are similar to discrete lines in the spectrum of quantum dots, as well as the unusual Landau-level energy spectrum of graphene in the presence of a strong magnetic field. The presence of flat bands crucially depends on whether or not there are odd or even electrons of H(F) atoms bound to graphene. Interestingly, we found that a fully hydrogenated (fluoridated) of a hexagon of graphene sheet with six hydrogen (fluorine) atoms sitting on top and bottom in consecutive order exhibits Dirac cones in the electronic band structure with a 20% smaller Fermi velocity as compared to the pristine graphene. Functionalizing graphene introduces various C-C bond lengths resulting in nonuniform strains. Such a nonuniform strain may induce a giant pseudomagnetic field in the system, resulting in quantum Hall effect. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000994364500006 | Publication Date | 2023-02-02 | |
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 | 3.7 | Times cited | 1 | Open Access | OpenAccess |
Notes | Approved | Most recent IF: 3.7; 2023 IF: 3.836 | |||
Call Number | UA @ admin @ c:irua:197431 | Serial | 8822 | ||
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Author | Rosenauer, A.; Schowalter, M.; Glas, F.; Lamoen, D. | ||||
Title | First-principles calculations of 002 structure factors for electron scattering in strained InxGa1-xAs | Type | A1 Journal article | ||
Year | 2005 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
Volume | 72 | Issue | 8 | Pages | 1-10 |
Keywords | A1 Journal article; Electron Microscopy for Materials Science (EMAT); | ||||
Abstract | This work provides values of electron scattering 002 structure factors for InxGa1-xAs as a function of the In concentration x=0 to 1. These results allow accurate compositional analysis of pseudomorphically grown InxGa1-xAs/GaAs layers by transmission electron microscopy methods relying on the chemical sensitivity of the (002) beam. The calculations go beyond the limits of the isolated atom approximation, because they take into account charge redistribution effects between atomic sites in the crystal, strain, and static atomic displacements. The computations were performed by the full potential linearized augmented plane-wave method using a generalized gradient approximation for the exchange and correlation part of the potential. The calculations of strained InxGa1-xAs correspond to the strain state in specimens with large, small, and intermediate thickness in the electron beam direction. Additionally, the effect of static atomic displacements is taken into account. All results are listed in a parameterized form. The calculated 002 structure factor vanishes at an In concentration of 16.4%. This value is in a good agreement with previously reported experimental measurements. Hence, our results are a significant improvement with respect to the isolated atom approximation which is conventionally applied in transmission electron microscopy simulations, and which predicts a value of 22.5%. | ||||
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Publisher | Place of Publication | Lancaster, Pa | Editor | ||
Language | Wos | 000231564600106 | Publication Date | 2005-08-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 42 | Open Access | |
Notes | Approved | Most recent IF: 3.836; 2005 IF: 3.185 | |||
Call Number | UA @ lucian @ c:irua:54918 | Serial | 1201 | ||
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Author | Shields, P.A.; Nicholas, R.J.; Peeters, F.M.; Beaumont, B.; Gibart, P. | ||||
Title | Free-carrier effects in gallium nitride epilayers: Valence-band dispersion | Type | A1 Journal article | ||
Year | 2001 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
Volume | 64 | Issue | 8 | Pages | 155303 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The dispersion of the A-valence-band in GaN has been deduced from the observation of high-index magnetoexcitonic states in polarized interband magnetoreflectivity and is found to be strongly nonparabolic with a mass in the range 1.2-1.8m(e). It matches the theory of Kim et al. [Phys. Rev. B 56, 7363 (1997)] extremely well, which also gives a strong k-dependent A-valence-band mass. A strong phonon coupling leads to quenching of the observed transitions at about an LO-phonon energy above the band gap and a strong nonparabolicity. The valence band was deduced from subtracting from the reduced dispersion the electron contribution with a model that includes a full treatment of the electron-phonon interaction. | ||||
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Publisher | Place of Publication | Lancaster, Pa | Editor | ||
Language | Wos | 000170623000005 | Publication Date | 2002-07-27 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0163-1829;1095-3795; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 13 | Open Access | |
Notes | Approved | Most recent IF: 3.836; 2001 IF: NA | |||
Call Number | UA @ lucian @ c:irua:37288 | Serial | 1274 | ||
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Author | Callewaert, V.; Saniz, R.; Barbiellini, B.; Bansil, A.; Partoens, B. | ||||
Title | Application of the weighted-density approximation to the accurate description of electron-positron correlation effects in materials | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 96 | Issue | 8 | Pages | 085135 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We discuss positron-annihilation lifetimes for a set of illustrative bulk materials within the framework of the weighted-density approximation (WDA). The WDA can correctly describe electron-positron correlations in strongly inhomogeneous systems, such as surfaces, where the applicability of (semi-)local approximations is limited. We analyze the WDA in detail and show that the electrons which cannot screen external charges efficiently, such as the core electrons, cannot be treated accurately via the pair correlation of the homogeneous electron gas. We discuss how this problem can be addressed by reducing the screening in the homogeneous electron gas by adding terms depending on the gradient of the electron density. Further improvements are obtained when core electrons are treated within the LDA and the valence electron using the WDA. Finally, we discuss a semiempirical WDA-based approach in which a sum rule is imposed to reproduce the experimental lifetimes. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000408342600003 | Publication Date | 2017-08-24 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 6 | Open Access | |
Notes | Fonds Wetenschappelijk Onderzoek, G. 0224.14N ; U.S. Department of Energy, DE-FG02-07ER46352 DE-AC02-05CH11231 DE-SC0012575 ; | Approved | Most recent IF: 3.836 | ||
Call Number | CMT @ cmt @c:irua:145703 | Serial | 4703 | ||
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Author | Xiao, Y.M.; Xu, W.; Peeters, F.M.; Van Duppen, B. | ||||
Title | Multicomponent plasmons in monolayer MoS2 with circularly polarized optical pumping | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 96 | Issue | 8 | Pages | 085405 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | By making use of circularly polarized light and electrostatic gating, monolayer molybdenum disulfide (ML – MoS2) can form a platform supporting multiple types of charge carriers. They can be discriminated by their spin, valley index, or whether they are electrons or holes. We investigate the collective properties of those charge carriers and are able to identify distinct plasmon modes. We analyze the corresponding dispersion relation, lifetime, and oscillator strength, and calculate the phase relation between the oscillations in the different components of the plasmon modes. All platforms in ML-MoS2 support a long-wavelength root q plasmon branch at zero kelvins. In addition to this, for an n-component system, n-1 distinct plasmon modes appear as acoustic modes with linear dispersion in the long-wavelength limit. These modes correspond to out-of-phase oscillations in the different fermion liquids and have, although being damped, a relatively long lifetime. Additionally, we also find distinct modes at large wave vectors that are more strongly damped by intraband processes. | ||||
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Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
Language | Wos | 000406861600001 | Publication Date | 2017-08-04 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 2 | Open Access | |
Notes | ; Y.M.X. acknowledges financial support from the China Scholarship Council (CSC). B.V.D. is supported by the Flemish Science Foundation (FWO-Vl) through a postdoctoral fellowship. This work was also supported by the National Natural Science Foundation of China (Grants No. 11574319 and No. 11304272), the Ministry of Science and Technology of China (Grant No. 2011YQ130018), the Department of Science and Technology of Yunnan Province, the Applied Basic Research Foundation of Yunnan Province (2013FD003), and the Chinese Academy of Sciences. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:145729 | Serial | 4745 | ||
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Author | Rezaei, M.; Sisakht, E.T.; Fazileh, F.; Aslani, Z.; Peeters, F.M. | ||||
Title | Tight-binding model investigation of the biaxial strain induced topological phase transition in GeCH3 | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 96 | Issue | 8 | Pages | 085441 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We propose a tight-binding (TB) model, that includes spin-orbit coupling (SOC), to describe the electronic properties of methyl-substituted germanane (GeCH3). This model gives an electronic spectrum in agreement with first principle results close to the Fermi level. Using the Z(2) formalism, we show that a topological phase transition from a normal insulator (NI) to a quantum spin Hall (QSH) phase occurs at 11.6% biaxial tensile strain. The sensitivity of the electronic properties of this system on strain, in particular its transition to the topological insulating phase, makes it very attractive for applications in strain sensors and other microelectronic applications. | ||||
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Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
Language | Wos | 000408570800004 | Publication Date | 2017-08-29 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 10 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:145697 | Serial | 4755 | ||
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Author | Chen, Q.; Li, L.L.; Peeters, F.M. | ||||
Title | Magnetic field dependence of electronic properties of MoS2 quantum dots with different edges | Type | A1 Journal article | ||
Year | 2018 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 97 | Issue | 8 | Pages | 085437 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Using the tight-binding approach, we investigate the energy spectrum of square, triangular, and hexagonal MoS2 quantum dots (QDs) in the presence of a perpendicular magnetic field. Novel edge states emerge in MoS2 QDs, which are distributed over the whole edge which we call ring states. The ring states are robust in the presence of spin-orbit coupling (SOC). The corresponding energy levels of the ring states oscillate as a function of the perpendicular magnetic field which are related to Aharonov-Bohm oscillations. Oscillations in the magnetic field dependence of the energy levels and the peaks in the magneto-optical spectrum emerge (disappear) as the ring states are formed (collapsed). The period and the amplitude of the oscillation decrease with the size of the MoS2 QDs. | ||||
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Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
Language | Wos | 000426042800009 | Publication Date | 2018-02-26 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 18 | Open Access | |
Notes | ; Q. Chen acknowledges financial support from the (China Scholarship Council (CSC)). This work was also supported by Hunan Provincial Natural Science Foundation of China (Grant No. 2015JJ2040) and by the Scientific Research Fund of Hunan Provincial Education Department (Grant No. 15A042). Additional support from the FLAG-ERA TRANS-2D-TMD is acknowledged. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:149905UA @ admin @ c:irua:149905 | Serial | 4941 | ||
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Author | Van der Donck, M.; Zarenia, M.; Peeters, F.M. | ||||
Title | Strong valley Zeeman effect of dark excitons in monolayer transition metal dichalcogenides in a tilted magnetic field | Type | A1 Journal article | ||
Year | 2018 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 97 | Issue | 8 | Pages | 081109 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The dependence of the excitonic photoluminescence (PL) spectrum of monolayer transition metal dichalcogenides (TMDs) on the tilt angle of an applied magnetic field is studied. Starting from a four-band Hamiltonian we construct a theory which quantitatively reproduces the available experimental PL spectra for perpendicular and in-plane magnetic fields. In the presence of a tilted magnetic field, we demonstrate that the dark exciton PL peaks brighten due to the in-plane component of the magnetic field and split for light with different circular polarizations as a consequence of the perpendicular component of the magnetic field. This splitting is more than twice as large as the splitting of the bright exciton peaks in tungsten-based TMDs. We propose an experimental setup that will allow for accessing the predicted splitting of the dark exciton peaks in the PL spectrum. | ||||
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Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
Language | Wos | 000425603600001 | Publication Date | 2018-02-21 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 21 | Open Access | |
Notes | ; This Rapid Communication was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD and by the Methusalem Foundation of the Flemish Government. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:149913UA @ admin @ c:irua:149913 | Serial | 4948 | ||
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Author | Yagmurcukardes, M.; Peeters, F.M.; Sahin, H. | ||||
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. | ||||
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Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
Language | Wos | 000442667200008 | Publication Date | 2018-08-24 | |
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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 | Bercx, M.; Partoens, B.; Lamoen, D. | ||||
Title | Quantitative modeling of secondary electron emission from slow-ion bombardment on semiconductors | Type | A1 Journal article | ||
Year | 2019 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 99 | Issue | 8 | Pages | 085413 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
Abstract | When slow ions incident on a surface are neutralized, the excess potential energy is passed on to an electron inside the surface, leading to emission of secondary electrons. The microscopic description of this process, as well as the calculation of the secondary electron yield, is a challenging problem due to its complexity as well as its sensitivity to surface properties. One of the first quantitative descriptions was articulated in the 1950s by Hagstrum, who based his calculation on a parametrization of the density of states of the material. In this paper, we present a model for calculating the secondary electron yield, derived from Hagstrum’s initial approach. We use first-principles density functional theory calculations to acquire the necessary input and introduce the concept of electron cascades to Hagstrum’s model in order to improve the calculated spectra, as well as remove its reliance on fitting parameters. We apply our model to He+ and Ne+ ions incident on Ge(111) and Si(111) and obtain yield spectra that match closely to the experimental results of Hagstrum. |
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000458367800010 | Publication Date | 2019-02-11 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 5 | Open Access | OpenAccess |
Notes | We would like to thank Prof. D. Depla for the useful discussions on the secondary electron yield. Furthermore, we acknowledge financial support of FWO-Vlaanderen through project G.0216.14N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWOVlaanderen and the Flemish Government-department EWI. | Approved | Most recent IF: 3.836 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:157174 | Serial | 5154 | ||
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Author | Bafekry, A.; Neek-Amal, M. | ||||
Title | Tuning the electronic properties of graphene-graphitic carbon nitride heterostructures and heterojunctions by using an electric field | Type | A1 Journal article | ||
Year | 2020 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
Volume | 101 | Issue | 8 | Pages | 085417-10 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Integration of graphene-based two-dimensional materials is essential for nanoelectronics applications. Using density-functional theory, we systematically investigate the electronic properties of vertically stacked graphene-graphitic carbon nitrides (GE/GCN). We also studied the covalently lateral stitched graphene-graphitic carbon nitrides (GE-GCN heterojunctions). The effects of perpendicular electric field on the electronic properties of six different heterostructures, i.e., (i) one layer of GE on top of a layer of CnNm with (n, m) = (3,1), (3,4), and (4,3) and (ii) three heterostructures CnNm/Cn'Nm', where (n, m) not equal (n', m') are elucidated. The most important calculated features are (i) the systems GE/C3N4, C3N/C3N4, GE-C3N, GE-C4N3, and C3N-C3N4 exhibit semiconducting characteristics having small band gaps of Delta(0)=20, 250, 100, 100, 80 meV, respectively while (ii) the systems GE/C4N3, C3N/C4N3, and C3N-C4N3 show ferromagnetic-metallic properties. In particular, we found that, in semiconducting heterostructures, the band gap increases nontrivially with increasing the absolute value of the applied perpendicular electric field. This work is useful for designing heterojunctions and heterostructures made of graphene and other two-dimensional materials such as those proposed in recent experiments [X. Liu and M. C. Hersam Sci. Adv. 5, 6444 (2019)]. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000515659700007 | Publication Date | 2020-02-26 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.7 | Times cited | 24 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 3.7; 2020 IF: 3.836 | ||
Call Number | UA @ admin @ c:irua:167760 | Serial | 6640 | ||
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Author | Ozbal, G.; Senger, R.T.; Sevik, C.; Sevincli, H. | ||||
Title | Ballistic thermoelectric properties of monolayer semiconducting transition metal dichalcogenides and oxides | Type | A1 Journal article | ||
Year | 2019 | Publication | Physical review B | Abbreviated Journal | |
Volume | 100 | Issue | 8 | Pages | 085415 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Combining first-principles calculations with Landauer-Mittiker formalism, ballistic thermoelectric transport properties of semiconducting two-dimensional transition metal dichalcogenides (TMDs) and oxides (TMOs) (namely MX2 with M = Cr, Mo, W, Ti, Zr, Hf; X = O, S, Se, Te) are investigated in their 2H and 1T phases. Having computed structural, as well as ballistic electronic and phononic transport properties for all structures, we report the thermoelectric properties of the semiconducting ones. We find that 2H phases of four of the studied structures have very promising thermoelectric properties, unlike their 1T phases. The maximum room temperature p-type thermoelectric figure of merit (ZT) of 1.57 is obtained for 2H-HfSe2, which can be as high as 3.30 at T = 800 K. Additionally, 2H-ZrSe2, 2H-ZrTe2, and 2H-HfS2 have considerable ZT values (both nand p-type), that are above 1 at room temperature. The 1T phases of Zr and Hf-based oxides possess relatively high power factors, however their high lattice thermal conductance values limit their ZT values to below 1 at room temperature. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000480389100007 | Publication Date | 2019-08-12 | |
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; WoS citing articles | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | no | |||
Call Number | UA @ admin @ c:irua:193773 | Serial | 7549 | ||
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Author | Demiroglu, I.; Sevik, C. | ||||
Title | Extraordinary negative thermal expansion of two-dimensional nitrides : a comparative ab initio study of quasiharmonic approximation and molecular dynamics simulations | Type | A1 Journal article | ||
Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
Volume | 103 | Issue | 8 | Pages | 085430 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Thermal expansion behavior of two-dimensional (2D) nitrides and graphene were studied by ab initio molecular dynamics (MD) simulations as well as quasiharmonic approximation (QHA). Anharmonicity of the acoustic phonon modes are related to the unusual negative thermal expansion (NTE) behavior of the nitrides. Our results also hint that direct ab initio MD simulations are a more elaborate method to investigate thermal expansion behavior of 2D materials than the QHA. Nevertheless, giant NTE coefficients are found for h-GaN and h-AlN within the covered temperature range 100-600 K regardless of the chosen computational method. This unusual NTE of 2D nitrides is reasoned with the out-of-plane oscillations related to the rippling behavior of the monolayers. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000620346100007 | Publication Date | 2021-02-22 | |
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 | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 3.836 | |||
Call Number | UA @ admin @ c:irua:176671 | Serial | 7956 | ||
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Author | Bekaert, J.; Aperis, A.; Partoens, B.; Oppeneer, P.M.; Milošević, M.V. | ||||
Title | Evolution of multigap superconductivity in the atomically thin limit : strain-enhanced three-gap superconductivity in monolayer MgB2 | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 96 | Issue | 9 | Pages | 094510 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Starting from first principles, we show the formation and evolution of superconducting gaps in MgB2 at its ultrathin limit. Atomically thin MgB2 is distinctly different from bulk MgB2 in that surface states become comparable in electronic density to the bulklike sigma and pi bands. Combining the ab initio electron-phonon coupling with the anisotropic Eliashberg equations, we showthat monolayer MgB2 develops three distinct superconducting gaps, on completely separate parts of the Fermi surface due to the emergent surface contribution. These gaps hybridize nontrivially with every extra monolayer added to the film owing to the opening of additional coupling channels. Furthermore, we reveal that the three-gap superconductivity in monolayer MgB2 is robust over the entire temperature range that stretches up to a considerably high critical temperature of 20 K. The latter can be boosted to >50K under biaxial tensile strain of similar to 4%, which is an enhancement that is stronger than in any other graphene-related superconductor known to date. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
Language | Wos | 000410166800008 | Publication Date | 2017-09-11 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 56 | Open Access | |
Notes | ; This work was supported by TOPBOF-UAntwerp, Research Foundation-Flanders (FWO), the Swedish Research Council (VR), and the Rontgen-Angstrom Cluster. The first-principles calculations have been carried out on the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Centre (VSC), supported financially by the Hercules Foundation and the Flemish Government (EWI Department). Eliashberg theory calculations were supported through the Swedish National Infrastructure for Computing (SNIC). ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:145623 | Serial | 4741 | ||
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Author | Michel, K.H.; Scuracchio, P.; Peeters, F.M. | ||||
Title | Sound waves and flexural mode dynamics in two-dimensional crystals | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 96 | Issue | 9 | Pages | 094302 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Starting from a Hamiltonian with anharmonic coupling between in-plane acoustic displacements and outof-plane (flexural) modes, we derived coupled equations of motion for in-plane displacements correlations and flexural mode density fluctuations. Linear response theory and time-dependent thermal Green's functions techniques are applied in order to obtain different response functions. As external perturbations we allow for stresses and thermal heat sources. The displacement correlations are described by a Dyson equation where the flexural density distribution enters as an additional perturbation. The flexural density distribution satisfies a kinetic equation where the in-plane lattice displacements act as a perturbation. In the hydrodynamic limit this system of coupled equations is at the basis of a unified description of elastic and thermal phenomena, such as isothermal versus adiabatic sound motion and thermal conductivity versus second sound. The general theory is formulated in view of application to graphene, two-dimensional h-BN, and 2H-transition metal dichalcogenides and oxides. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
Language | Wos | 000409246200003 | Publication Date | 2017-09-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 6 | Open Access | |
Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:145630 | Serial | 4751 | ||
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Author | Tsirlin, A.A.; Rousochatzakis, I.; Filimonov, D.; Batuk, D.; Frontzek, M.; Abakumov, A.M. | ||||
Title | Spin-reorientation transitions in the Cairo pentagonal magnet Bi4Fe5O13F | Type | A1 Journal article | ||
Year | 2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 96 | Issue | 9 | Pages | 094420 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We show that interlayer spins play a dual role in the Cairo pentagonal magnet Bi4Fe5O13F, on one hand mediating the three-dimensional magnetic order, and on the other driving spin-reorientation transitions both within and between the planes. The corresponding sequence of magnetic orders unraveled by neutron diffraction and Mossbauer spectroscopy features two orthogonal magnetic structures described by opposite local vector chiralities, and an intermediate, partly disordered phase with nearly collinear spins. A similar collinear phase has been predicted theoretically to be stabilized by quantum fluctuations, but Bi4Fe5O13F is very far from the relevant parameter regime. While the observed in-plane reorientation cannot be explained by any standard frustration mechanism, our ab initio band-structure calculations reveal strong single-ion anisotropy of the interlayer Fe3+ spins that turns out to be instrumental in controlling the local vector chirality and the associated interlayer order. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000411161700002 | Publication Date | 2017-09-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 7 | Open Access | OpenAccess |
Notes | We are grateful to J.-M. Perez-Mato and Dmitry Khalyavin for valuable discussions on the magnetic structures and symmetries. D.F. and A.A. are grateful to the Russian Science Foundation (Grant No. 14-13-00680) for support. A.T. was supported by the Federal Ministry for Education and Research through the Sofja Kovalevskaya Award of the Alexander von Humboldt Foundation. This work is based on experiments performed at the Swiss spallation neutron source SINQ, Paul Scherrer Institut, Villigen, Switzerland. | Approved | Most recent IF: 3.836 | ||
Call Number | EMAT @ emat @c:irua:146748 | Serial | 4774 | ||
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Author | Vargas Paredes, A.A.; Shanenko, A.A.; Vagov, A.; Milošević, M.V.; Perali, A. | ||||
Title | Crossband versus intraband pairing in superconductors: signatures and consequences of the interplay | Type | A1 Journal article | ||
Year | 2020 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
Volume | 101 | Issue | 9 | Pages | 094516-94517 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We analyze the paradigmatic competition between intraband and crossband Cooper-pair formation in twoband superconductors, neglected in most works to date. We derive the phase-sensitive gap equations and describe the crossover between the intraband-dominated and the crossband-dominated regimes, delimited by a “gapless” state. Experimental signatures of crosspairing comprise notable gap splitting in the excitation spectrum, non-BCS behavior of gaps versus temperature, as well as changes in the pairing symmetry as a function of temperature. The consequences of these findings are illustrated on the examples of MgB2 and Ba0.6K0.4Fe2As2. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000522074900002 | Publication Date | 2020-03-27 | |
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 | 3.7 | Times cited | 14 | Open Access | |
Notes | ; This collaborative work was fostered within the international Multi Super network on Multi-condensate Superconductivity and Superfluidity [70]. The authors thank Andrea Guidini for his help during the initial stage of this work and Laura Fanfarillo for useful discussions. This work was partially supported by the Italian MIUR through the PRIN 2015 program (Contract No. 2015C5SEJJ001) and the Research Foundation -Flanders (FWO). A.A.V.-P. acknowledges support by the joint doctoral program and by the Erasmus+ exchange between the University of Antwerp and the University of Camerino. M.V.M. gratefully acknowledges support from a Visiting Professorship at the University of Camerino. A.S. and A.V. acknowledge support from the CAPES/Print Grant, Process No. 88887.333666/ 2019-00 (Brazil) and the Russian Science Foundation Project No. 18-12-00429, respectively. ; | Approved | Most recent IF: 3.7; 2020 IF: 3.836 | ||
Call Number | UA @ admin @ c:irua:168605 | Serial | 6479 | ||
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Author | van Duijn, F.; Osca, J.; Sorée, B. | ||||
Title | Skyrmion elongation, duplication, and rotation by spin-transfer torque under spatially varying spin current | Type | A1 Journal article | ||
Year | 2021 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
Volume | 104 | Issue | 9 | Pages | 094426 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The effect of the spatially varying spin current on a skyrmion is numerically investigated. It is shown that an inhomogeneous current density induces an elongation of the skyrmion. This elongation can be controlled using current pulses of different strength and duration. Long current pulses lead to a splitting that forms two replicas of the initial skyrmion while for short pulses the elongated skyrmion relaxes back to its initial circular state through rotation in the MHz-GHz frequency range. The frequency is dependent on the strength of the damping coefficient. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000704236000002 | Publication Date | 2021-09-21 | |
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 | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 3.836 | |||
Call Number | UA @ admin @ c:irua:182467 | Serial | 7018 | ||
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Author | Lazarevic, N.; Baum, A.; Milosavljevic, A.; Peis, L.; Stumberger, R.; Bekaert, J.; Solajic, A.; Pesic, J.; Wang, A.; Scepanovic, M.; Abeykoon, A.M.M.; Milošević, M.V.; Petrovic, C.; Popovic, Z.V.; Hackl, R. | ||||
Title | Evolution of lattice, spin, and charge properties across the phase diagram of Fe1-xSx | Type | A1 Journal article | ||
Year | 2022 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 106 | Issue | 9 | Pages | 094510-94519 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | A Raman scattering study covering the entire substitution range of the FeSe1-xSx solid solution is presented. Data were taken as a function of sulfur concentration x for 0 <= x <= 1, of temperature and of scattering symmetry. All types of excitations including phonons, spins, and charges are analyzed in detail. It is observed that the energy and width of the iron-related B-1g phonon mode vary continuously across the entire range of sulfur substitution. The A(1g) chalcogenide mode disappears above x = 0.23 and reappears at a much higher energy for x = 0.69. In a similar way the spectral features appearing at finite doping in A(1g) symmetry vary discontinuously. The magnetic excitation centered at approximately 500 cm(-1) disappears above x = 0.23 where the A(1g) lattice excitations exhibit a discontinuous change in energy. The low-energy mode associated with fluctuations displays maximal intensity at the nematostructural transition and thus tracks the phase boundary. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000917933500004 | Publication Date | 2022-09-19 | |
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 | 3.7 | Times cited | Open Access | OpenAccess | |
Notes | Approved | Most recent IF: 3.7 | |||
Call Number | UA @ admin @ c:irua:194397 | Serial | 7304 | ||
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Author | Cadorim, L.R.; de Toledo, L.V.; Ortiz, W.A.; Berger, J.; Sardella, E. | ||||
Title | Closed vortex state in three-dimensional mesoscopic superconducting films under an applied transport current | Type | A1 Journal article | ||
Year | 2023 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 107 | Issue | 9 | Pages | 094515-94518 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | By using the full 3D generalized time-dependent Ginzbug-Landau equation, we study a long superconducting film of finite width and thickness under an applied transport current. We show that, for sufficiently large thickness, the vortices and the antivortices become curved before they annihilate each other. As they approach the center of the sample, their ends combine, producing a single closed vortex. We also determine the critical values of the thickness for which the closed vortex sets in for different values of the Ginzburg-Ladau parameter. Finally, we propose a model of how to detect a closed vortex experimentally. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000957055800002 | Publication Date | 2023-03-20 | |
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 | 3.7 | Times cited | Open Access | Not_Open_Access | |
Notes | Approved | Most recent IF: 3.7; 2023 IF: 3.836 | |||
Call Number | UA @ admin @ c:irua:196079 | Serial | 7673 | ||
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Author | Pascucci, F.; Conti, S.; Perali, A.; Tempère, J.; Neilson, D. | ||||
Title | Effects of intralayer correlations on electron-hole double-layer superfluidity | Type | A1 Journal article | ||
Year | 2024 | Publication | Physical review B | Abbreviated Journal | |
Volume | 109 | Issue | 9 | Pages | 094512-94515 |
Keywords | A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) | ||||
Abstract | We investigate the intralayer correlations acting within the layers in a superfluid system of electron -hole spatially separated layers. In this system, superfluidity is predicted to be almost exclusively confined to the Bose-Einstein condensate (BEC) and crossover regimes where the electron -hole pairs are well localized. In this case, Hartree-Fock is an excellent approximation for the intralayer correlations. We find in the BEC regime that the effect of the intralayer correlations on superfluid properties is negligible but in the BCS-BEC crossover regime the superfluid gap is significantly weakened by the intralayer correlations. This is caused by the intralayer correlations boosting the number of low -energy particle -hole excitations that drive the screening. We further find that the intralayer correlations suppress the predicted phenomenon in which the average pair size passes through a minimum as the crossover regime is traversed. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 001199662600001 | Publication Date | 2024-03-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 3.7 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 3.7; 2024 IF: 3.836 | |||
Call Number | UA @ admin @ c:irua:205476 | Serial | 9145 | ||
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Author | Moura, V.N.; Chaves, A.; Peeters, F.M.; Milošević, M.V. | ||||
Title | McMillan-Ginzburg-Landau theory of singularities and discommensurations in charge density wave states of transition metal dichalcogenides | Type | A1 Journal article | ||
Year | 2024 | Publication | Physical review B | Abbreviated Journal | |
Volume | 109 | Issue | 9 | Pages | 094507-94511 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | The McMillan-Ginzburg-Landau (MGL) model for charge density waves (CDW) is employed in a systematic phenomenological study of the different phases that have been probed in recent experiments involving transition metal dichalcogenides. We implemented an efficient imaginary time evolution method to solve the MGL equations, which enabled us to investigate the role of different coupling parameters on the CDW patterns and to perform calculations with different energy functionals that lead to several experimentally observed singularities in the CDW phase profiles. In particular, by choosing the appropriate energy functionals, we were able to obtain phases that go beyond the well-known periodic phase slips (discommensurations), exhibiting also topological defects (i.e., vortex-antivortex pairs), domain walls where the CDW order parameter is suppressed, and even CDW with broken rotational symmetry. Finally, we briefly discuss the effect of these different CDW phases on the profile and critical temperature of the competing superconducting state. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 001199651500001 | Publication Date | 2024-03-11 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | 3.7 | Times cited | Open Access | ||
Notes | Approved | Most recent IF: 3.7; 2024 IF: 3.836 | |||
Call Number | UA @ admin @ c:irua:205491 | Serial | 9158 | ||
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Author | Singh, S.K.; Neek-Amal, M.; Costamagna, S.; Peeters, F.M. | ||||
Title | Rippling, buckling, and melting of single- and multilayer MoS2 | Type | A1 Journal article | ||
Year | 2015 | Publication | Physical Review B | Abbreviated Journal | Phys Rev B |
Volume | 91 | Issue | 91 | Pages | 014101 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Large-scale atomistic simulations using the reactive empirical bond order force field approach is implemented to investigate thermal and mechanical properties of single-layer (SL) and multilayer (ML) molybdenum disulfide (MoS2). The amplitude of the intrinsic ripples of SL MoS2 are found to be smaller than those exhibited by graphene (GE). Furthermore, because of the van der Waals interaction between layers, the out-of-plane thermal fluctuations of ML MoS2 decreases rapidly with increasing number of layers. This trend is confirmed by the buckling transition due to uniaxial stress which occurs for a significantly larger applied tension as compared to graphene. For SL MoS2, the melting temperature is estimated to be 3700 K which occurs through dimerization followed by the formation of small molecules consisting of two to five atoms. When different types of vacancies are inserted in the SL MoS2 it results in a decrease of both the melting temperature as well as the stiffness. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Lancaster, Pa | Editor | ||
Language | Wos | 000347921300001 | Publication Date | 2015-01-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1098-0121;1550-235X; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 40 | Open Access | |
Notes | ; This work is supported by the ESF-Eurographene project CONGRAN, the Flemish Science Foundation (FWO-VI), and the Methusalem Foundation of the Flemish Government. We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. We would like to thanks Prof. Douglas E. Spearot [26] for giving us the implemented parameters of Mo-S in LAMMPS. ; | Approved | Most recent IF: 3.836; 2015 IF: 3.736 | ||
Call Number | c:irua:123834 | Serial | 2909 | ||
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Author | da Costa, D.R.; Zarenia, M.; Chaves, A.; Farias, G.A.; Peeters, F.M. | ||||
Title | Magnetic field dependence of energy levels in biased bilayer graphene quantum dots | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 93 | Issue | 93 | Pages | 085401 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Using the tight-binding approach, we study the influence of a perpendicular magnetic field on the energy levels of hexagonal, triangular, and circular bilayer graphene (BLG) quantum dots (QDs) with zigzag and armchair edges. We obtain the energy levels for AB (Bernal)-stacked BLG QDs in both the absence and the presence of a perpendicular electric field (i.e., biased BLG QDs). We find different regions in the spectrum of biased QDs with respect to the crossing point between the lowest-electron and -hole Landau levels of a biased BLG sheet. Those different regions correspond to electron states that are localized at the center, edge, or corner of the BLG QD. Quantum Hall corner states are found to be absent in circular BLG QDs. The spatial symmetry of the carrier density distribution is related to the symmetry of the confinement potential, the position of zigzag edges, and the presence or absence of interlayer inversion symmetry. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000369402400008 | Publication Date | 2016-02-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 22 | Open Access | |
Notes | ; This work was financially supported by CNPq, under Contract No. NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES Foundation under the Process No. BEX 7178/13-1, the Flemish Science Foundation (FWO-Vl), the Bilateral programme between CNPq and FWO-Vl, and the Brazilian Program Science Without Borders (CsF). ; | Approved | Most recent IF: 3.836 | ||
Call Number | c:irua:131623 | Serial | 4038 | ||
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Author | Bacaksiz, C.; Cahangirov, S.; Rubio, A.; Senger, R.T.; Peeters, F.M.; Sahin, H. | ||||
Title | Bilayer SnS2 : tunable stacking sequence by charging and loading pressure | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 93 | Issue | 93 | Pages | 125403 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Employing density functional theory-based methods, we investigate monolayer and bilayer structures of hexagonal SnS2, which is a recently synthesized monolayer metal dichalcogenide. Comparison of the 1H and 1T phases of monolayer SnS2 confirms the ground state to be the 1T phase. In its bilayer structure we examine different stacking configurations of the two layers. It is found that the interlayer coupling in bilayer SnS2 is weaker than that of typical transition-metal dichalcogenides so that alternative stacking orders have similar structural parameters and they are separated with low energy barriers. A possible signature of the stacking order in the SnS2 bilayer has been sought in the calculated absorbance and reflectivity spectra. We also study the effects of the external electric field, charging, and loading pressure on the characteristic properties of bilayer SnS2. It is found that (i) the electric field increases the coupling between the layers at its preferred stacking order, so the barrier height increases, (ii) the bang gap value can be tuned by the external E field and under sufficient E field, the bilayer SnS2 can become a semimetal, (iii) the most favorable stacking order can be switched by charging, and (iv) a loading pressure exceeding 3 GPa changes the stacking order. The E-field tunable band gap and easily tunable stacking sequence of SnS2 layers make this 2D crystal structure a good candidate for field effect transistor and nanoscale lubricant applications. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000371405000005 | Publication Date | 2016-03-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 38 | Open Access | |
Notes | ; The calculations were performed at TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). C.B., H.S., and R.T.S. acknowledge support from TUBITAK Project No. 114F397. H.S. is supported by an FWO Pegasus Marie Curie Fellowship. S.C. and A.R. acknowledge financial support from the Marie Curie grant FP7-PEOPLE-2013-IEF Project No. 628876, the European Research Council (ERC-2010-AdG-267374), and Spanish grant Grupos Consolidados (IT578-13). S.C. acknowledges support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 115F388. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:132345 | Serial | 4144 | ||
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Author | Van der Donck, M.; Peeters, F.M.; Van Duppen, B. | ||||
Title | Comment on “Creating in-plane pseudomagnetic fields in excess of 1000 T by misoriented stacking in a graphene bilayer” | Type | Editorial | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 93 | Issue | 93 | Pages | 247401 |
Keywords | Editorial; Condensed Matter Theory (CMT) | ||||
Abstract | In a recent paper [Phys. Rev. B 89, 125418 (2014)], the authors argue that it is possible to map the electronic properties of twisted bilayer graphene to those of bilayer graphene in an in-plane magnetic field. However, their description of the low-energy dynamics of twisted bilayer graphene is restricted to the extended zone scheme and therefore neglects the effects of the superperiodic structure. If the energy spectrum is studied in the supercell Brillouin zone, we find that the comparison with an in-plane magnetic field fails because (i) the energy spectra of the two situations exhibit different symmetries and (ii) the low-energy spectra are very different. | ||||
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Publisher | Amer physical soc | Place of Publication | College pk | Editor | |
Language | Wos | 000377802200009 | Publication Date | 2016-06-14 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 6 | Open Access | |
Notes | ; ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:134601 | Serial | 4151 | ||
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Author | Roy, P.; Torun, E.; de Groot, R.A. | ||||
Title | Effect of doping and elastic properties in (Mn,Fe)2(Si,P) | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 93 | Issue | 93 | Pages | 094110 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | Mixed magnetism (the coexistence of strong and weak magnetism in one material) is regarded as the origin of the giant magnetocaloric effect (GMCE). A good example is (Mn,Fe)(2)(Si,P), which is established as one of the best magnetocaloric materials available. Tuning the material properties are essential for optimizing its performance, and a straightforward way to do that is by doping. In this article, an ab initio electronic structure method was used to calculate the structure and magnetic properties of 3d-transition-metal-doped (Mn,Fe)(2)(Si,P) materials for magnetocaloric applications (transition metals are Cr, Co, Mn, Ni, Cu). For a steady performance, the material should be mechanically stable. A detailed analysis of the elastic constants shows that the mechanical stability of the (Mn,Fe)(2)(Si,P) system increases significantly by doping with boron without affecting the magnetic properties. Insights of the influence of doping enable future studies to understand and predict bettermagnetocaloric materials. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000372712100001 | Publication Date | 2016-03-25 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 9 | Open Access | |
Notes | ; This work is part of an Industrial Partnership Programme (IPP I28) of Fundamenteel Onderzoek der Materie (FOM) (The Netherlands) and co-financed by BASF New Business. The authors would like to thank Phuong Thao Nguyen and Dr. Gilles A. de Wijs for very useful discussions. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:133192 | Serial | 4164 | ||
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Author | Craco, L.; Carara, S.S.; da Silva Pereira, T.A.; Milošević, M.V. | ||||
Title | Electronic states in an atomistic carbon quantum dot patterned in graphene | Type | A1 Journal article | ||
Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
Volume | 93 | Issue | 93 | Pages | 155417 |
Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
Abstract | We reveal the emergence of metallicKondo clouds in an atomistic carbon quantum dot, realized as a single-atom junction in a suitably patterned graphene nanoflake. Using density functional dynamical mean-field theory (DFDMFT) we show how correlation effects lead to striking features in the electronic structure of our device, and how those are enhanced by the electron-electron interactions when graphene is patterned at the atomistic scale. Our setup provides a well-controlled environment to understand the principles behind the orbital-selective Kondo physics and the interplay between orbital and spin degrees of freedom in carbon-based nanomaterials, which indicate new pathways for spintronics in atomically patterned graphene. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000373760900004 | Publication Date | 2016-04-12 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 2469-9950;2469-9969; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.836 | Times cited | 6 | Open Access | |
Notes | ; L.C.'s work is supported by CNPq (Proc. No. 307487/2014-8). Acknowledgment (L.C.) is also made to G. Seifert for discussions and the Department of Theoretical Chemistry at Technical University Dresden for hospitality. T.A.S.P. thanks PRONEX/CNPq/FAPEMAT 850109/2009 for financial support. M.V.M. acknowledges support from Research Foundation-Flanders (FWO), TOPBOF, and the CAPES-PVE program. ; | Approved | Most recent IF: 3.836 | ||
Call Number | UA @ lucian @ c:irua:133260 | Serial | 4171 | ||
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