| Records |
| Author |
Van Pottelberge, R.; Zarenia, M.; Vasilopoulos, P.; Peeters, F.M. |
| Title |
Graphene quantum dot with a Coulomb impurity : subcritical and supercritical regime |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume  |
95 |
Issue |
24 |
Pages |
245410 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We study the influence of confinement on the atomic collapse due to a Coulomb impurity placed at the center of a graphene quantum dot of radius R. We apply the zigzag or infinite-mass boundary condition and consider both a point-size and a finite-size impurity. As a function of the impurity strength Za, the energy spectra are discrete. In the case of the zigzag boundary condition, the degenerate (with respect to the angular momentum m) zero-energy levels are pulled down in energy as Z alpha increases, and they remain below epsilon = – Z alpha. Our results show that the energy levels exhibit a 1/R dependence in the subcritical regime [Z alpha < |km + 1/2|, k = 1 (-1) for the K (K') valley]. In the supercritical regime (Z alpha > |km + 1/2|) we find a qualitatively very different behavior where the levels decrease as a function of R in a nonmonotonic manner. While the valley symmetry is preserved in the presence of the impurity, we find that the impurity breaks electron-hole symmetry. We further study the energy spectrum of zigzag quantum dots in gapped graphene. Our results show that as the gap increases, the lowest electron states are pushed into the gap by the impurity. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
| Language |
|
Wos |
000403072400005 |
Publication Date |
2017-06-13 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
13 |
Open Access |
|
| Notes |
; We thank Massoud Ramezani-Masir and Dean Moldovan for fruitful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the Methusalem funding of the Flemish Government, and by the Canadian NSERC Grant No. OGP0121756 (P. V.). ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ lucian @ c:irua:144197 |
Serial |
4661 |
| Permanent link to this record |
| |
|
| |
| Author |
Mirzakhani, M.; Zarenia, M.; Vasilopoulos, P.; Peeters, F.M. |
| Title |
Electrostatically confined trilayer graphene quantum dots |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Physical review B |
Abbreviated Journal |
|
| Volume |
95 |
Issue |
15 |
Pages |
155434 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Electrically gating of trilayer graphene (TLG) opens a band gap offering the possibility to electrically engineer TLG quantum dots. We study the energy levels of such quantum dots and investigate their dependence on a perpendicular magnetic field B and different types of stacking of the graphene layers. The dots are modeled as circular and confined by a truncated parabolic potential which can be realized by nanostructured gates or position-dependent doping. The energy spectra exhibit the intervalley symmetry E-K(e) (m) = -E (h)(K') (m) for the electron (e) and hole (h) states, where m is the angular momentum quantum number and K and K' label the two valleys. The electron and hole spectra for B = 0 are twofold degenerate due to the intervalley symmetry E-K (m) = E-K' [-(m + 1)]. For both ABC [alpha = 1.5 (1.2) for large (small) R] and ABA (alpha = 1) stackings, the lowest-energy levels show approximately a R-alpha dependence on the dot radius R in contrast with the 1/R-3 one for ABC-stacked dots with infinite-mass boundary. As functions of the field B, the oscillator strengths for dipole-allowed transitions differ drastically for the two types of stackings. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000399797200003 |
Publication Date |
2017-04-22 |
| 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 |
|
Times cited |
6 |
Open Access |
|
| Notes |
|
Approved |
no |
| Call Number |
UA @ admin @ c:irua:152652 |
Serial |
7878 |
| Permanent link to this record |
| |
|
| |
| Author |
Van der Donck, M.; Zarenia, M.; Peeters, F.M. |
| Title |
Excitons and trions in monolayer transition metal dichalcogenides : a comparative study between the multiband model and the quadratic single-band model |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
96 |
Issue |
3 |
Pages |
035131 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The electronic and structural properties of excitons and trions in monolayer transition metal dichalcogenides are investigated using both a multiband and a single- band model. In the multiband model we construct the excitonic Hamiltonian in the product base of the single-particle states at the conduction and valence band edges. We decouple the corresponding energy eigenvalue equation and solve the resulting differential equation self-consistently, using the finite element method (FEM), to determine the energy eigenvalues and the wave functions. As a comparison, we also consider the simple single-band model which is often used in numerical studies. We solve the energy eigenvalue equation using the FEM as well as with the stochastic variational method (SVM) in which a variational wave function is expanded in a basis of a large number of correlated Gaussians. We find good agreement between the results of both methods, as well as with other theoretical works for excitons, and we also compare with available experimental data. For trions the agreement between both methods is not as good due to our neglect of angular correlations when using the FEM. Finally, when comparing the two models, we see that the presence of the valence bands in the mutiband model leads to differences with the single- band model when (interband) interactions are strong. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
| Language |
|
Wos |
000405706600005 |
Publication Date |
2017-07-18 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
50 |
Open Access |
|
| Notes |
; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD. ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ lucian @ c:irua:145209 |
Serial |
4716 |
| Permanent link to this record |
| |
|
| |
| Author |
Mirzakhani, M.; Zarenia, M.; Vasilopoulos, P.; Ketabi, S.A.; Peeters, F.M. |
| Title |
Landau levels in biased graphene structures with monolayer-bilayer interfaces |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
96 |
Issue |
12 |
Pages |
125430 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The electron energy spectrum in monolayer-bilayer-monolayer and in bilayer-monolayer-bilayer graphene structures is investigated and the effects of a perpendicular magnetic field and electric bias are studied. Different types of monolayer-bilayer interfaces are considered as zigzag (ZZ) or armchair (AC) junctions which modify considerably the bulk Landau levels (LLs) when the spectra are plotted as a function of the center coordinate of the cyclotron orbit. Far away from the two interfaces, one obtains the well-known LLs for extended monolayer or bilayer graphene. The LL structure changes significantly at the two interfaces or junctions where the valley degeneracy is lifted for both types of junctions, especially when the distance between them is approximately equal to the magnetic length. Varying the nonuniform bias and the width of this junction-to-junction region in either structure strongly influence the resulting spectra. Significant differences exist between ZZ and AC junctions in both structures. The densities of states (DOSs) for unbiased structures are symmetric in energy whereas those for biased structures are asymmetric. An external bias creates interface LLs in the gaps between the LLs of the unbiased system in which the DOS can be quite small. Such a pattern of LLs can be probed by scanning tunneling microscopy. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
| Language |
|
Wos |
000411321800003 |
Publication Date |
2017-09-21 |
| 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 |
6 |
Open Access |
|
| Notes |
; This work was supported by the BOF-UA (Bijzonder Onderzoeks Fonds), the Canadian NSERC through Grant No. OGP0121756 (P.V.), and the Methusalem Program of the Flemish Government. ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ lucian @ c:irua:146746 |
Serial |
4787 |
| Permanent link to this record |
| |
|
| |
| Author |
Nascimento, J.S.; da Costa, D.R.; Zarenia, M.; Chaves, A.; Pereira, J.M., Jr. |
| Title |
Magnetic properties of bilayer graphene quantum dots in the presence of uniaxial strain |
Type |
A1 Journal article |
| Year |
2017 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
96 |
Issue |
11 |
Pages |
115428 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Using the tight-binding approach coupled with mean-field Hubbard model, we theoretically study the effect of mechanical deformations on the magnetic properties of bilayer graphene (BLG) quantum dots (QDs). Results are obtained for AA-and AB(Bernal)-stacked BLG QDs, considering different geometries (hexagonal, triangular and square shapes) and edge types (armchair and zigzag edges). In the absence of strain, our results show that (i) the magnetization is affected by taking different dot sizes only for hexagonal BLG QDs with zigzag edges, exhibiting different critical Hubbard interactions, and (ii) the magnetization does not depend on the interlayer hopping energies, except for the geometries with zigzag edges and AA stacking. In the presence of in-plane and uniaxial strain, for all geometries we obtain two different magnetization regimes depending on the applied strain amplitude. The appearance of such different regimes is due to the breaking of layer and sublattice symmetries in BLG QDs. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
| Language |
|
Wos |
000411077400008 |
Publication Date |
2017-09-18 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
4 |
Open Access |
|
| Notes |
; This work was financially supported by CNPq, FUNCAP, CAPES Foundation, the Flemish Science Foundation (FWO-Vl), and the Brazilian Program Science Without Borders (CsF). ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ lucian @ c:irua:146751 |
Serial |
4788 |
| Permanent link to this record |
| |
|
| |
| 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. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| 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 |
| Permanent link to this record |
| |
|
| |
| Author |
Van Pottelberge, R.; Zarenia, M.; Peeters, F.M. |
| Title |
Comment on “Impurity spectra of graphene under electric and magnetic fields” |
Type |
Editorial |
| Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
97 |
Issue |
20 |
Pages |
207403 |
| Keywords |
Editorial; Condensed Matter Theory (CMT) |
| Abstract |
In a recent paper [Phys. Rev. B 89, 155403 (2014)], the authors investigated the spectrum of a Coulomb impurity in graphene in the presence of magnetic and electric fields using the coupled series expansion approach. In the first part of their paper, they investigated how Coulomb impurity states collapse in the presence of a perpendicular magnetic field. We argue that the obtained spectrum does not give information about the atomic collapse and that their interpretation of the spectrum regarding atomic collapse is not correct. We also argue that the obtained results are only valid up to the dimensionless charge vertical bar alpha vertical bar = 0.5 and, to obtain correct results for alpha > 0.5, a proper regularization of the Coulomb interaction is required. Here we present the correct numerical results for the spectrum for arbitrary values of alpha. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
Amer physical soc |
Place of Publication |
College pk |
Editor |
|
| Language |
|
Wos |
000433288800015 |
Publication Date |
2018-05-29 |
| 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 |
5 |
Open Access |
|
| Notes |
; We thank Matthias Van der Donck for fruitful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem funding of the Flemish Government. ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ lucian @ c:irua:152042UA @ admin @ c:irua:152042 |
Serial |
5017 |
| Permanent link to this record |
| |
|
| |
| Author |
Van der Donck, M.; Zarenia, M.; Peeters, F.M. |
| Title |
Excitons, trions, and biexcitons in transition-metal dichalcogenides : magnetic-field dependence |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
97 |
Issue |
19 |
Pages |
195408 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The influence of a perpendicular magnetic field on the binding energy and structural properties of excitons, trions, and biexcitons in monolayers of semiconducting transition metal dichalcogenides (TMDs) is investigated. The stochastic variational method (SVM) with a correlated Gaussian basis is used to calculate the different properties of these few-particle systems. In addition, we present a simplified variational approach which supports the SVM results for excitons as a function of magnetic field. The exciton diamagnetic shift is compared with recent experimental results, and we extend this concept to trions and biexcitons. The effect of a local potential fluctuation, which we model by a circular potential well, on the binding energy of trions and biexcitons is investigated and found to significantly increase the binding of those excitonic complexes. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
| Language |
|
Wos |
000432024800005 |
Publication Date |
2018-05-07 |
| 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 |
3.836 |
Times cited |
36 |
Open Access |
|
| Notes |
; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for M.V.D.D. ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ lucian @ c:irua:151521UA @ admin @ c:irua:151521 |
Serial |
5025 |
| Permanent link to this record |
| |
|
| |
| Author |
Saberi-Pouya, S.; Zarenia, M.; Perali, A.; Vazifehshenas, T.; Peeters, F.M. |
| Title |
High-temperature electron-hole superfluidity with strong anisotropic gaps in double phosphorene monolayers |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
97 |
Issue |
17 |
Pages |
174503 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Excitonic superfluidity in double phosphorene monolayers is investigated using the BCS mean-field equations. Highly anisotropic superfluidity is predicted where we found that the maximum superfluid gap is in the Bose-Einstein condensate (BEC) regime along the armchair direction and in the BCS-BEC crossover regime along the zigzag direction. We estimate the highest Kosterlitz-Thouless transition temperature with maximum value up to similar to 90 K with onset carrier densities as high as 4 x 10(12) cm(-2). This transition temperature is significantly larger than what is found in double electron-hole few-layers graphene. Our results can guide experimental research toward the realization of anisotropic condensate states in electron-hole phosphorene monolayers. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
| Language |
|
Wos |
000431986100002 |
Publication Date |
2018-05-02 |
| 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; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
17 |
Open Access |
|
| Notes |
; We thank David Neilson for helpful discussions. This work was partially supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program of the Flemish government and Iran Ministry of Science, Research and Technology. ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ lucian @ c:irua:151533UA @ admin @ c:irua:151533 |
Serial |
5028 |
| Permanent link to this record |
| |
|
| |
| Author |
Van Pottelberge, R.; Zarenia, M.; Peeters, F.M. |
| Title |
Magnetic field dependence of atomic collapse in bilayer graphene |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
98 |
Issue |
11 |
Pages |
115406 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The spectrum of a Coulomb impurity in bilayer graphene is investigated as function of the strength of a perpendicular magnetic field for different values of the angular quantum number m and for different values of the gate voltage. We point out fundamental differences between the results from the two-band and four-band model. The supercritical instability and fall-to-center phenomena are investigated in the presence of a magnetic field. We find that in the four-band model the fall-to-center phenomenon occurs as in monolayer graphene, while this is not the case in the two-band model. We find that in a magnetic field the supercritical instability manifests itself as a series of anticrossings in the hole part of the spectrum for states coming from the low-energy band. However, we also find very distinct anticrossings in the electron part of the spectrum that continue into the hole part, which are related to the higher energy band of the four-band model. At these anticrossings, we find a very sharp peak in the probability density close to the impurity, reminiscent for the fall-to-center phenomenon. In this paper, these peculiar and interesting effects are studied for different magnetic field, interlayer coupling, and bias potential strengths. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
| Language |
|
Wos |
000443671900010 |
Publication Date |
2018-09-04 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
3 |
Open Access |
|
| Notes |
; We thank Matthias Van der Donck and Ben Van Duppen for fruitful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem funding of the Flemish Government. ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ lucian @ c:irua:153654UA @ admin @ c:irua:153654 |
Serial |
5113 |
| Permanent link to this record |
| |
|
| |
| Author |
Saberi-Pouya, S.; Zarenia, M.; Vazifehshenas, T.; Peeters, F.M. |
| Title |
Anisotropic charge density wave in electron-hole double monolayers : applied to phosphorene |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
98 |
Issue |
24 |
Pages |
245115 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The possibility of an inhomogeneous charge density wave phase is investigated in a system of two coupled electron and hole monolayers separated by a hexagonal boron nitride insulating layer. The charge-density-wave state is induced through the assumption of negative compressibility of electron/hole gases in a Coulomb drag configuration between the electron and hole sheets. Under equilibrium conditions, we derive analytical expressions for the density oscillation along the zigzag and armchair directions. We find that the density modulation not only depends on the sign of the compressibility but also on the anisotropy of the low-energy bands. Our results are applicable to any two-dimensional system with anisotropic parabolic bands, characterized by different effective masses. For equal effective masses, i.e., isotropic energy bands, our results agree with Hroblak et al. [Phys. Rev. B 96, 075422 (2017)]. Our numerical results are applied to phosphorene. |
| Address |
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| Corporate Author |
|
Thesis |
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| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000452995600001 |
Publication Date |
2018-12-12 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
3.836 |
Times cited |
|
Open Access |
|
| Notes |
; This work was partially supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program of the Flemish government and Iran Science Elites Federation. ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:156233 |
Serial |
5195 |
| Permanent link to this record |
| |
|
| |
| 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. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000512772200004 |
Publication Date |
2020-02-13 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.7 |
Times cited |
13 |
Open Access |
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| 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 |
| Permanent link to this record |
| |
|
| |
| Author |
Van der Donck, M.; Zarenia, M.; Peeters, F.M. |
| Title |
Reply to “Comment on `Excitons, trions, and biexcitons in transition-metal dichalcogenides: Magnetic-field dependence'” |
Type |
Editorial |
| Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
101 |
Issue |
12 |
Pages |
127402 |
| Keywords |
Editorial; Condensed Matter Theory (CMT) |
| Abstract |
In the Comment, the authors state that the separation of the relative and center of mass variables in our work is not correct. Here we point out that there is a typographical error, i.e., qi instead of -e, in two of our equations which, when corrected, makes the Comment redundant. Within the ansatzes mentioned in our paper all our results are correct, in contrast to the claims of the Comment. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000519990800011 |
Publication Date |
2020-03-18 |
| Series Editor |
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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 |
| Impact Factor |
3.7 |
Times cited |
|
Open Access |
|
| Notes |
; ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:167680 |
Serial |
6594 |
| Permanent link to this record |
| |
|
| |
| Author |
Abdullah, H.M.; Zarenia, M.; Bahlouli, H.; Peeters, F.M.; Van Duppen, B. |
| Title |
Gate tunable layer selectivity of transport in bilayer graphene nanostructures |
Type |
A1 Journal article |
| Year |
2016 |
Publication |
Europhysics letters |
Abbreviated Journal |
Epl-Europhys Lett |
| Volume |
113 |
Issue |
113 |
Pages |
17006 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Recently it was found that bilayer graphene may exhibit regions with and without van der Waals coupling between the two layers. We show that such structures can exhibit a strong layer selectivity when current flows through the coupled region and that this selectivity can be tuned by means of electrostatic gating. Analysing how this effect depends on the type of bilayer stacking, the potential on the gates and the smoothness of the boundary between the coupled and decoupled regions, we show that nearly perfect layer selectivity is achievable in these systems. This effect can be further used to realise a tunable layer switch. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000371479500024 |
Publication Date |
2016-01-28 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0295-5075 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.957 |
Times cited |
15 |
Open Access |
|
| Notes |
HMA and HB acknowledge the support of the Saudi Center for Theoretical Physics (SCTP) for their generous support and the support of King Fahd University of Petroleum and Minerals under physics research group projects RG1306-1 and RG01306-2. This work is supported by the Flemish Science Foundation (FWO-Vl) by a PhD grant (BVD) and a post-doctoral fellowship (MZ). |
Approved |
Most recent IF: 1.957 |
| Call Number |
c:irua:131909 c:irua:131909 |
Serial |
4037 |
| Permanent link to this record |
| |
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| |
| Author |
Zarenia, M.; Conti, S.; Peeters, F.M.; Neilson, D. |
| Title |
Coulomb drag in strongly coupled quantum wells : temperature dependence of the many-body correlations |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
115 |
Issue |
20 |
Pages |
202105 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We investigate the effect of the temperature dependence of many-body correlations on hole-hole Coulomb drag in strongly coupled GaAs/GaAlAs double quantum wells. For arbitrary temperatures, we obtained the correlations using the classical-map hypernetted-chain approach. We compare the temperature dependence of the resulting drag resistivities rho D(T) at different densities with rho D(T) calculated assuming correlations fixed at zero temperature. Comparing the results with those when correlations are completely neglected, we confirm that correlations significantly increase the drag. We find that the drag becomes sensitive to the temperature dependence of T greater than or similar to 2TF, twice the Fermi temperature. Our results show excellent agreement with available experimental data. Published under license by AIP Publishing. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000498619400007 |
Publication Date |
2019-11-14 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
|
Edition |
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| ISSN |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.411 |
Times cited |
1 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.411 |
| Call Number |
UA @ admin @ c:irua:165135 |
Serial |
6291 |
| Permanent link to this record |
| |
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| |
| Author |
Zarenia, M.; Hamilton, A.R.; Peeters, F.M.; Neilson, D. |
| Title |
Multiband mechanism for the sign reversal of Coulomb drag observed in double bilayer graphene heterostructures |
Type |
A1 Journal article |
| Year |
2018 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
| Volume |
121 |
Issue |
3 |
Pages |
036601 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Coupled 2D sheets of electrons and holes are predicted to support novel quantum phases. Two experiments of Coulomb drag in electron-hole (e-h) double bilayer graphene (DBLG) have reported an unexplained and puzzling sign reversal of the drag signal. However, we show that this effect is due to the multiband character of DBLG. Our multiband Fermi liquid theory produces excellent agreement and captures the key features of the experimental drag resistance for all temperatures. This demonstrates the importance of multiband effects in DBLG: they have a strong effect not only on superfluidity, but also on the drag. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
New York, N.Y. |
Editor |
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| Language |
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Wos |
000438883600008 |
Publication Date |
2018-07-18 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0031-9007 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
8.462 |
Times cited |
7 |
Open Access |
|
| Notes |
; We are grateful to Cory Dean, Emanuel Tutuc, and their research groups for discussing details of their experiments with us. This work was partially supported by the Flemish Science Foundation (FWO-Vl), the Methusalem program of the Flemish government, and the Australian Government through the Australian Research Council Centre of Excellence in Future Low-Energy Electronics Technologies (Project No. CE170100039). D. N. acknowledges support from the University of Camerino FAR project CESEMN. ; |
Approved |
Most recent IF: 8.462 |
| Call Number |
UA @ lucian @ c:irua:152416UA @ admin @ c:irua:152416 |
Serial |
5116 |
| Permanent link to this record |
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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. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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| Language |
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Wos |
000433977200017 |
Publication Date |
2018-05-23 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.068 |
Times cited |
3 |
Open Access |
|
| Notes |
; 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 |
| Permanent link to this record |
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| Author |
Grujić, M.; Zarenia, M.; Tadić, M.; Peeters, F.M. |
| Title |
Interband optical absorption in a circular graphene quantum dot |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Physica scripta |
Abbreviated Journal |
Phys Scripta |
| Volume |
T149 |
Issue |
|
Pages |
014056-014056,4 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We investigate the energy levels and optical properties of a circular graphene quantum dot in the presence of an external magnetic field perpendicular to the dot. Based on the Dirac-Weyl equation and assuming zero outward current at the edge of the dot we present the results for two different types of boundary conditions, i.e. infinite-mass (IMBC) and zigzag boundary conditions. We found that the dot with zigzag edges displays a zero-energy state in the energy spectra while this is not the case for the IMBCs. For both boundary conditions, the confinement becomes dominated by the magnetic field, where the energy levels converge to the Landau levels as the magnetic field increases. The effect of boundary conditions on the electron-and hole-energy states is found to affect the interband absorption spectra, where we found larger absorption in the case of IMBCs. The selection rules for interband optical transitions are determined and discussed for both boundary conditions. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Stockholm |
Editor |
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| Language |
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Wos |
000303523500057 |
Publication Date |
2012-04-27 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0031-8949;1402-4896; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.28 |
Times cited |
5 |
Open Access |
|
| Notes |
; This work was supported by the EuroGraphene program of the ESF (project CONGRAN), the Ministry of Education and Science of Serbia, the Belgian Science Policy (IAP) and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 1.28; 2012 IF: 1.032 |
| Call Number |
UA @ lucian @ c:irua:99136 |
Serial |
1688 |
| Permanent link to this record |
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| Author |
Matulis, A.; Zarenia, M.; Peeters, F.M. |
| Title |
Wave fronts and packets in 1D models of different meta-materials : graphene, left-handed media and transmission line |
Type |
A1 Journal article |
| Year |
2015 |
Publication |
Physica status solidi: B: basic research |
Abbreviated Journal |
Phys Status Solidi B |
| Volume |
252 |
Issue |
252 |
Pages |
2330-2338 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
A comparative study is made of the propagation of wave packets and fronts in three different meta-media, i.e. graphene, left-handed media (LHM) and transmission lines, using one-dimensional models. It is shown that a potential step in graphene influences only the frequency of the electronic wave, i.e., the particular spectrum branch (electron or hole) to which the wave belongs to, while the envelop function (the wave front or packet form) remains unchanged. Although the model for a vacuum and LHM interface is similar to that of the potential step in graphene, the solutions are quite different due to differences in the chirality of the waves. Comparing the propagation of wave fronts and packets in a standard transmission line and its meta-analog we demonstrate that the propagating packets in the meta-line are much more deformed as compared to the standard one, including broadening, asymmetry and even the appearance of fast moving precursors. This influence is seen not only in the case of packets with steep fronts but in soft Gaussian packets as well. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Berlin |
Editor |
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| Language |
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Wos |
000362722300025 |
Publication Date |
2015-07-20 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0370-1972 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.674 |
Times cited |
1 |
Open Access |
|
| Notes |
; This work was financially supported by the Flemish Science Foundation (FWO-Vl), the Methusalem foundation of the Flemish government, and the European Social Fund under the Global Grant Measure (Grant No. VP1-3.1-SMM-07-K-02-046). ; |
Approved |
Most recent IF: 1.674; 2015 IF: 1.489 |
| Call Number |
UA @ lucian @ c:irua:128776 |
Serial |
4277 |
| Permanent link to this record |
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| Author |
Zarenia, M.; Vasilopoulos, P.; Pourtolami, N.; Peeters, F.M. |
| Title |
Landau-level dispersion and the quantum Hall plateaus in bilayer graphene |
Type |
P1 Proceeding |
| Year |
2013 |
Publication |
AIP conference proceedings |
Abbreviated Journal |
|
| Volume |
1566 |
Issue |
|
Pages |
275-276 |
| Keywords |
P1 Proceeding; Condensed Matter Theory (CMT) |
| Abstract |
We study the quantum Hall effect (QHE) in bilayer graphene using the Kubo-Greenwood formula. At zero temperature the Hall conductivity sigma(yx) is given by sigma(yx) – 4(N + 1)e(2)/h with N the index of the highest occupied Landau level (LL). Including the dispersion of the LLs and their width, due to e. g. scattering by impurities, produces the plateau of the n = 0 LL in agreement with experimental results on doped samples and similar theoretical results on single-layer graphene plateaus widen with impurity concentration. Further, the evaluated resistivity rho(xx) exhibits a strong, oscillatory dependence on the electron concentration. Explicit results are obtained for delta-function impurities. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
New York |
Editor |
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| Language |
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Wos |
000331793000137 |
Publication Date |
2014-01-03 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
|
ISBN |
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Additional Links |
UA library record; WoS full record |
| Impact Factor |
|
Times cited |
|
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the European Science Foundation (project CONGRAN) and the Canadian NSERC Grant No. OGP0121756. ; |
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:115871 |
Serial |
1770 |
| Permanent link to this record |
