| Records |
| Author |
Van Pottelberge, R.; Van Duppen, B.; Peeters, F.M. |
| Title |
Electrical dipole on gapped graphene : bound states and atomic collapse |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
98 |
Issue |
16 |
Pages |
165420 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We investigate the energy spectrum, wave functions, and local density of states of an electrical dipole placed on a sheet of gapped graphene as function of the charge strength Z alpha for different sizes of the dipole and for different regularization parameters. The dipole is modeled as consisting of a positive and negative charge. Bound states are found within the gap region with some energy levels that anticross and others that cross as function of the impurity strength Z alpha. The anticrossings are more pronounced and move to higher charges Z alpha when the length of the dipole decreases. These energy levels turn into atomic collapse states when they enter the positive (or negative) energy continuum. A smooth transition from the single-impurity behavior to the dipole one is observed: The states diving towards the continuum in the single-impurity case are gradually replaced by a series of anticrossings that represent a continuation of the diving states in the single-impurity case. By studying the local density of states at the edge of the dipole we show how the series of anticrossings persist in the positive and negative continuum. |
| Address |
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| Corporate Author |
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Thesis |
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Publisher  |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
| Language |
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Wos |
000447302700010 |
Publication Date |
2018-10-23 |
| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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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 |
8 |
Open Access |
|
| Notes |
; We thank Matthias Van der Donck for fruitful discussions. This work was supported by the Research Foundation of Flanders (FWO-V1) through an aspirant research grant for R.V.P. and a postdoctoral grant for B.V.D. ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ lucian @ c:irua:154728UA @ admin @ c:irua:154728 |
Serial |
5094 |
| Permanent link to this record |
| |
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| |
| Author |
Mulkers, J.; Hals, K.M.D.; Leliaert, J.; Milošević, M.V.; Van Waeyenberge, B.; Everschor-Sitte, K. |
| Title |
Effect of boundary-induced chirality on magnetic textures in thin films |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
98 |
Issue |
6 |
Pages |
064429 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
In the quest for miniaturizing magnetic devices, the effects of boundaries and surfaces become increasingly important. Here we show how the recently predicted boundary-induced Dzyaloshinskii-Moriya interaction (DMI) affects the magnetization of ferromagnetic films with a C-infinity v symmetry and a perpendicular magnetic anisotropy. For an otherwise uniformly magnetized film, we find a surface twist when the magnetization in the bulk is canted by an in-plane external field. This twist at the surfaces caused by the boundary-induced DMI differs from the common canting caused by internal DMI observed at the edges of a chiral magnet. Furthermore, we find that the surface twist due to the boundary-induced DMI strongly affects the width of the domain wall at the surfaces. We also find that the skyrmion radius increases in the depth of the film, with the average size of the skyrmion increasing with boundary-induced DMI. This increase suggests that the boundary-induced DMI contributes to the stability of the skyrmion. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
| Language |
|
Wos |
000443394600004 |
Publication Date |
2018-08-31 |
| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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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 |
9 |
Open Access |
|
| Notes |
; The authors thank Matthias Sitte and Andre Thiaville for fruitful discussions. This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vlaanderen) through Project No. G098917N and the German Research Foundation (DFG) under the Project No. EV 196/2-1. J.L. is supported by the Ghent University Special Research Fund with a BOF postdoctoral fellowship. ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ lucian @ c:irua:153706UA @ admin @ c:irua:153706 |
Serial |
5093 |
| Permanent link to this record |
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| Author |
Nakhaee, M.; Ketabi, S.A.; Peeters, F.M. |
| Title |
Dirac nodal line in bilayer borophene : tight-binding model and low-energy effective Hamiltonian |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
98 |
Issue |
11 |
Pages |
115413 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Bilayer hexagonal borophene, which is bound together through pillars, is a novel topological semimetal. Using density functional theory, we investigate its electronic band structure and show that it is a Dirac material which exhibits a nodal line. A tight-binding model was constructed based on the Slater-Koster approach, which accurately models the electronic spectrum. We constructed an effective four-band model Hamiltonian to describe the spectrum near the nodal line. This Hamiltonian can be used as a new platform to study the new properties of nodal line semimetals. We found that the nodal line is created by edge states and is very robust against perturbations and impurities. Breaking symmetries can split the nodal line, but cannot open a gap. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
| Language |
|
Wos |
000443916200007 |
Publication Date |
2018-09-06 |
| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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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 |
19 |
Open Access |
|
| Notes |
; This work was supported by the Methusalem program of the Flemish government and the graphene FLAG-ERA project TRANS-2D-TMD. ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ lucian @ c:irua:153649UA @ admin @ c:irua:153649 |
Serial |
5090 |
| Permanent link to this record |
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| Author |
Müller-Caspary, K.; Duchamp, M.; Roesner, M.; Migunov, V.; Winkler, F.; Yang, H.; Huth, M.; Ritz, R.; Simson, M.; Ihle, S.; Soltau, H.; Wehling, T.; Dunin-Borkowski, R.E.; Van Aert, S.; Rosenauer, A. |
| Title |
Atomic-scale quantification of charge densities in two-dimensional materials |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
98 |
Issue |
12 |
Pages |
121408 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The charge density is among the most fundamental solid state properties determining bonding, electrical characteristics, and adsorption or catalysis at surfaces. While atomic-scale charge densities have as yet been retrieved by solid state theory, we demonstrate both charge density and electric field mapping across a mono-/bilayer boundary in 2D MoS2 by momentum-resolved scanning transmission electron microscopy. Based on consistency of the four-dimensional experimental data, statistical parameter estimation and dynamical electron scattering simulations using strain-relaxed supercells, we are able to identify an AA-type bilayer stacking and charge depletion at the Mo-terminated layer edge. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
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| Language |
|
Wos |
000445508200004 |
Publication Date |
2018-09-24 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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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 |
10 |
Open Access |
OpenAccess |
| Notes |
; K.M.-C. acknowledges funding from the Initiative and Network Fund of the Helmholtz Association (VH-NG-1317) within the framework of the Helmholtz Young Investigator Group moreSTEM at Forschungszentrum Julich, Germany. ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ lucian @ c:irua:153621 |
Serial |
5078 |
| Permanent link to this record |
| |
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| |
| Author |
Torun, E.; Sahin, H.; Chaves, A.; Wirtz, L.; Peeters, F.M. |
| Title |
Ab initio and semiempirical modeling of excitons and trions in monolayer TiS3 |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
98 |
Issue |
7 |
Pages |
075419 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We explore the electronic and the optical properties of monolayer TiS3, which shows in-plane anisotropy and is composed of a chain-like structure along one of the lattice directions. Together with its robust direct band gap, which changes very slightly with stacking order and with the thickness of the sample, the anisotropic physical properties of TiS3 make the material very attractive for various device applications. In this study, we present a detailed investigation on the effect of the crystal anisotropy on the excitons and the trions of the TiS3 monolayer. We use many-body perturbation theory to calculate the absorption spectrum of anisotropic TiS3 monolayer by solving the Bethe-Salpeter equation. In parallel, we implement and use a Wannier-Mott model for the excitons that takes into account the anisotropic effective masses and Coulomb screening, which are obtained from ab initio calculations. This model is then extended for the investigation of trion states of monolayer TiS3. Our calculations indicate that the absorption spectrum of monolayer TiS3 drastically depends on the polarization of the incoming light, which excites different excitons with distinct binding energies. In addition, the binding energies of positively and the negatively charged trions are observed to be distinct and they exhibit an anisotropic probability density distribution. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
| Language |
|
Wos |
000442342100002 |
Publication Date |
2018-08-21 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
10 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the FLAG-ERA project TRANS-2D-TMD. H.S. acknowledges financial support from TUBITAK under Project No. 117F095. A.C. acknowledges support from the Brazilian Research Council (CNPq), through the PRONEX/FUNCAP and Science Without Borders programs, and from the Lemann Foundation. E.T. and L.W. acknowledge support from the National Research Fund, Luxembourg (IN-TER/ANR/13/20/NANOTMD). ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ lucian @ c:irua:153721UA @ admin @ c:irua:153721 |
Serial |
5076 |
| Permanent link to this record |
