Records |
Author |
Van der Donck, M.; De Beule, C.; Partoens, B.; Peeters, F.M.; Van Duppen, B. |
Title |
Piezoelectricity in asymmetrically strained bilayer graphene |
Type |
A1 Journal article |
Year |
2016 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
Volume |
3 |
Issue |
3 |
Pages |
035015 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study the electronic properties of commensurate faulted bilayer graphene by diagonalizing the one-particle Hamiltonian of the bilayer system in a complete basis of Bloch states of the individual graphene layers. Our novel approach is very general and can be easily extended to any commensurate graphene-based heterostructure. Here, we consider three cases: (i) twisted bilayer graphene, (ii) bilayer graphene where triaxial stress is applied to one layer and (iii) bilayer graphene where uniaxial stress is applied to one layer. We show that the resulting superstructures can be divided into distinct classes, depending on the twist angle or the magnitude of the induced strain. The different classes are distinguished from each other by the interlayer coupling mechanism, resulting in fundamentally different low-energy physics. For the cases of triaxial and uniaxial stress, the individual graphene layers tend to decouple and we find significant charge transfer between the layers. In addition, this piezoelectric effect can be tuned by applying a perpendicular electric field. Finally, we show how our approach can be generalized to multilayer systems. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
IOP Publishing |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000384072500003 |
Publication Date |
2016-08-31 |
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 |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
6.937 |
Times cited |
10 |
Open Access |
|
Notes |
; This work was supported by the Research Foundation-Flanders (FWO-Vl) through aspirant research grants to MVDD, CDB, and BVD. ; |
Approved |
Most recent IF: 6.937 |
Call Number |
UA @ lucian @ c:irua:137203 |
Serial |
4361 |
Permanent link to this record |
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|
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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 |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
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Language |
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Wos |
000405706600005 |
Publication Date |
2017-07-18 |
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; 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 |
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|
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Author |
Wang, W.; Van Duppen, B.; Van der Donck, M.; Peeters, F.M. |
Title |
Magnetopolaron effect on shallow-impurity states in the presence of magnetic and intense terahertz laser fields in the Faraday configuration |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
97 |
Issue |
6 |
Pages |
064108 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The magnetopolaron effect on shallow-impurity states in semiconductors is investigated when subjected simultaneously to a magnetic field and an intense terahertz laser field within the Faraday configuration. We use a time-dependent nonperturbative theory to describe electron interactions. The externally applied fields are exactly included via a laser-dressed interaction potential. Through a variational approach we evaluate the binding energy of the shallow-impurity states. We find that the interaction strength of the laser-dressed Coulomb potential can not only be enhanced but also weakened by varying the two external fields. In this way, the binding energy can be tuned by the external fields and red-or blue-shifted with respect to the static binding energy. In the nonresonant polaron region, a magnetopolaron correction that includes the effects of photon process is observed. In the resonant polaron region, moreover, the resonant magnetopolaron effect accompanied by the emission and absorption of a single photon is distinctly observed. This can be modulated to be far away from the reststrahlen band. The intriguing findings of this paper can be observed experimentally and, in turn, provide a way to measure the strength of the electron-phonon interaction. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
Language |
|
Wos |
000426041900004 |
Publication Date |
2018-02-26 |
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 |
; This work was supported by the National Natural Science Foundation of China (Grants No. 11404214 and No. 11455015) and the China Scholarship Council (CSC), Anhui Provincial Natural Science Foundation (Grant No. 1408085QA13), Key Projects of Anhui Provincial Department of Education (Grants No. KJ2017A406 and No. KJ2017A401). B.V.D. was financially supported by the Research Science Foundation-Flanders (FWO-Vl) through a postdoctoral fellowship and M.V.d.D. was financially supported by the Research Science Foundation-Flanders (FWO-Vl) through a doctoral fellowship. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:149906UA @ admin @ c:irua:149906 |
Serial |
4942 |
Permanent link to this record |
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|
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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. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
|
Language |
|
Wos |
000425603600001 |
Publication Date |
2018-02-21 |
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; 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 |
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|
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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 |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
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Language |
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Wos |
000432024800005 |
Publication Date |
2018-05-07 |
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; 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 |
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|
|
Author |
Van der Donck, M.; Peeters, F.M. |
Title |
Rich many-body phase diagram of electrons and holes in doped monolayer transition metal dichalcogenides |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
98 |
Issue |
11 |
Pages |
115432 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We use a variational technique to study the many-body phase diagram of electrons and holes in n-doped and p-doped monolayer transition metal dichalcogenides (TMDs). We find a total of four different phases. (i) A fully spin polarized and valley polarized ferromagnetic state. (ii) A state with no global spin polarization but with spin polarization in each valley separately, i.e., spin-valley locking. (iii) A state with spin polarization in one of the valleys and little to no spin polarization in the other valley. (iv) A paramagnetic state with no valley polarization. These phases are separated by first-order phase transitions and are determined by the particle density and the dielectric constant of the substrate. We find that in the presence of a perpendicular magnetic field the four different phases persist. In the case of n-doped MoS2, a fifth phase, which is completely valley polarized but not spin polarized, appears for magnetic fields larger than 7 T and for magnetic fields larger than 23 T completely replaces the second phase. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
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Language |
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Wos |
000445507000009 |
Publication Date |
2018-09-24 |
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; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
8 |
Open Access |
|
Notes |
; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD and by the FLAG-ERA project TRANS-2D-TMD. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:153622UA @ admin @ c:irua:153622 |
Serial |
5125 |
Permanent link to this record |
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Author |
Van der Donck, M.; Peeters, F.M. |
Title |
Interlayer excitons in transition metal dichalcogenide heterostructures |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
98 |
Issue |
11 |
Pages |
115104 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Starting from the single-particle Dirac Hamiltonian for charge carriers in monolayer transition metal dichalcogenides (TMDs), we construct a four-band Hamiltonian describing interlayer excitons consisting of an electron in one TMD layer and a hole in the other TMD layer. An expression for the electron-hole interaction potential is derived, taking into account the effect of the dielectric environment above, below, and between the two TMD layers as well as polarization effects in the transition metal layer and in the chalcogen layers of the TMD layers. We calculate the interlayer exciton binding energy and average in-plane interparticle distance for different TMD heterostructures. The effect of different dielectric environments on the exciton binding energy is investigated and a remarkable dependence on the dielectric constant of the barrier between the two layers is found, resulting from competing effects as a function of the in-plane and out-of-plane dielectric constants of the barrier. The polarization effects in the chalcogen layers, which in general reduce the exciton binding energy, can lead to an increase in binding energy in the presence of strong substrate effects by screening the substrate. The excitonic absorbance spectrum is calculated and we show that the interlayer exciton peak depends linearly on a perpendicular electric field, which agrees with recent experimental results. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
American Physical Society |
Place of Publication |
New York, N.Y |
Editor |
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Language |
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Wos |
000443671900004 |
Publication Date |
2018-09-04 |
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 |
|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
41 |
Open Access |
|
Notes |
; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD and by the FLAG-ERA project TRANS-2D-TMD. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:153653UA @ admin @ c:irua:153653 |
Serial |
5110 |
Permanent link to this record |
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Author |
Abdullah, H.M.; Van der Donck, M.; Bahlouli, H.; Peeters, F.M.; Van Duppen, B. |
Title |
Graphene quantum blisters : a tunable system to confine charge carriers |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
Volume |
112 |
Issue |
21 |
Pages |
213101 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Due to Klein tunneling, electrostatic confinement of electrons in graphene is not possible. This hinders the use of graphene for quantum dot applications. Only through quasi-bound states with finite lifetime has one achieved to confine charge carriers. Here, we propose that bilayer graphene with a local region of decoupled graphene layers is able to generate bound states under the application of an electrostatic gate. The discrete energy levels in such a quantum blister correspond to localized electron and hole states in the top and bottom layers. We find that this layer localization and the energy spectrum itself are tunable by a global electrostatic gate and that the latter also coincides with the electronic modes in a graphene disk. Curiously, states with energy close to the continuum exist primarily in the classically forbidden region outside the domain defining the blister. The results are robust against variations in size and shape of the blister which shows that it is a versatile system to achieve tunable electrostatic confinement in graphene. Published by AIP Publishing. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
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Language |
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Wos |
000433140900025 |
Publication Date |
2018-05-22 |
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 |
0003-6951; 1077-3118 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.411 |
Times cited |
9 |
Open Access |
|
Notes |
; H.M.A. and H.B. acknowledge the Saudi Center for Theoretical Physics (SCTP) for their generous support and the support of KFUPM under physics research group Project Nos. RG1502-1 and RG1502-2. This work was supported by the Flemish Science Foundation (FWO-Vl) by a post-doctoral fellowship (B.V.D.) and a doctoral fellowship (M.V.d.D.). ; |
Approved |
Most recent IF: 3.411 |
Call Number |
UA @ lucian @ c:irua:151505UA @ admin @ c:irua:151505 |
Serial |
5027 |
Permanent link to this record |
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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. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
Amer physical soc |
Place of Publication |
College pk |
Editor |
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Language |
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Wos |
000377802200009 |
Publication Date |
2016-06-14 |
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 |
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Edition |
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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 |
Permanent link to this record |
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Author |
Van der Donck, M.; Peeters, F.M.; Van Duppen, B. |
Title |
Transport properties of bilayer graphene in a strong in-plane magnetic field |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
93 |
Issue |
93 |
Pages |
115423 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A strong in-plane magnetic field drastically alters the low-energy spectrum of bilayer graphene by separating the parabolic energy dispersion into two linear Dirac cones. The effect of this dramatic change on the transport properties strongly depends on the orientation of the in-plane magnetic field with respect to the propagation direction of the charge carriers and the angle at which they impinge on the electrostatic potentials. For magnetic fields oriented parallel to the potential boundaries an additional propagating mode that results from the splitting into Dirac cones enhances the transmission probability for charge carriers tunneling through the potentials and increases the corresponding conductance. Our results show that the chiral suppression of transmission at normal incidence, reminiscent of bilayer graphene's 2 pi Berry phase, is turned into a chiral enhancement when the magnetic field increases, thus indicating a transition from a bilayer to a monolayer-like system at normal incidence. Further, we find that the typical transmission resonances stemming from confinement in a potential barrier are shifted to higher energy and are eventually transformed into antiresonances with increasing magnetic field. For magnetic fields oriented perpendicular to the potential boundaries we find a very pronounced transition from a bilayer system to two separated monolayer-like systems with Klein tunneling emerging at certain incident angles symmetric around 0, which also leaves a signature in the conductance. For both orientations of the magnetic field, the transmission probability is still correctly described by pseudospin conservation. Finally, to motivate the large in-plane magnetic field, we show that its energy spectrum can be mimicked by specific lattice deformations such as a relative shift of one of the layers. With this equivalence we introduce the notion of an in-plane pseudomagnetic field. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
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Place of Publication |
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Editor |
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Language |
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Wos |
000372409900006 |
Publication Date |
2016-03-21 |
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 |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
11 |
Open Access |
|
Notes |
; This work was supported by Fonds Wetenschappelijk Onderzoek (FWO-Vl) through an aspirant research grant to M.V.D.D. and B.V.D. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ lucian @ c:irua:133197 |
Serial |
4267 |
Permanent link to this record |
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Author |
Van der Donck, M.; Peeters, F.M. |
Title |
Excitonic complexes in anisotropic atomically thin two-dimensional materials : black phosphorus and TiS3 |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
98 |
Issue |
23 |
Pages |
235401 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The effect of anisotropy in the energy spectrum on the binding energy and structural properties of excitons, trions, and biexcitons is investigated. To this end we employ the stochastic variational method with a correlated Gaussian basis. We present results for the binding energy of different excitonic complexes in black phosphorus (bP) and TiS3 and compare them with recent results in the literature when available, for which we find good agreement. The binding energies of excitonic complexes in bP are larger than those in TiS3. We calculate the different average interparticle distances in bP and TiS3 and show that excitonic complexes in bP are strongly anisotropic whereas in TiS3 they are almost isotropic, even though the constituent particles have an anisotropic energy spectrum. This is also confirmed by the correlation functions. |
Address |
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Corporate Author |
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Thesis |
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Publisher ![sorted by Publisher field, descending order (down)](img/sort_desc.gif) |
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Place of Publication |
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Editor |
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Language |
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Wos |
000452003400009 |
Publication Date |
2018-12-03 |
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; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
10 |
Open Access |
|
Notes |
; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD and by the FLAG-ERA project TRANS-2D-TMD. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ admin @ c:irua:156247 |
Serial |
5211 |
Permanent link to this record |
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Author |
Van der Donck, M.; Peeters, F.M. |
Title |
Spectrum of exciton states in monolayer transition metal dichalcogenides : angular momentum and Landau levels |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
99 |
Issue |
11 |
Pages |
115439 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A four-band exciton Hamiltonian is constructed starting from the single-particle Dirac Hamiltonian for charge carriers in monolayer transition metal dichalcogenides (TMDs). The angular part of the exciton wave function can be separated from the radial part, in the case of zero center of mass momentum excitons, by exploiting the eigenstates of the total exciton angular momentum operator with which the Hamiltonian commutes. We explain why this approach fails for excitons with finite center of mass momentum or in the presence of a perpendicular magnetic field and present an approximation to resolve this issue. We calculate the (binding) energy and average interparticle distance of different excited exciton states in different TMDs and compare these with results available in the literature. Remarkably, we find that the intervalley exciton ground state in the -/+ K valley has angular momentum j = +/- 1, which is due to the pseudospin of the separate particles. The exciton mass and the exciton Landau levels are calculated and we find that the degeneracy of exciton states with opposite relative angular momentum is altered by a magnetic field. |
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Wos |
000462896400004 |
Publication Date |
2019-03-28 |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
10 |
Open Access |
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Notes |
; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for MVDD and by the FLAG-ERA project TRANS-2D-TMD. ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ admin @ c:irua:159406 |
Serial |
5230 |
Permanent link to this record |
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Author |
Van der Donck, M. |
Title |
Excitonic complexes in transition metal dichalcogenides and related materials |
Type |
Doctoral thesis |
Year |
2019 |
Publication |
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Abbreviated Journal |
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Volume |
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Issue |
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Pages |
224 p. |
Keywords |
Doctoral thesis; Condensed Matter Theory (CMT) |
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Edition |
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Additional Links |
UA library record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:162525 |
Serial |
5412 |
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Author |
Conti, S.; Van der Donck, M.; Perali, A.; Peeters, F.M.; Neilson, D. |
Title |
Doping-dependent switch from one- to two-component superfluidity in coupled electron-hole van der Waals heterostructures |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
Volume |
101 |
Issue |
22 |
Pages |
220504-220506 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The hunt for high-temperature superfluidity has received new impetus from the discovery of atomically thin stable materials. Electron-hole superfluidity in coupled MoSe2-WSe2 monolayers is investigated using a mean-field multiband model that includes band splitting caused by strong spin-orbit coupling. This splitting leads to a large energy misalignment of the electron and hole bands which is strongly modified by interchanging the doping of the monolayers. The choice of doping determines if the superfluidity is tunable from one to two components. |
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Editor |
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Language |
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Wos |
000538941900002 |
Publication Date |
2020-06-09 |
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 |
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 |
12 |
Open Access |
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Notes |
; This work was partially supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl), the Methusalem Foundation, and the FLAG-ERA project TRANS2DTMD. We thank A. R. Hamilton and A. Vargas-Paredes for useful discussions. ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
Call Number |
UA @ admin @ c:irua:170201 |
Serial |
6489 |
Permanent link to this record |
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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. |
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Wos |
000519990800011 |
Publication Date |
2020-03-18 |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
3.7 |
Times cited |
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Open Access |
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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 |
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Author |
Van der Donck, M.; Conti, S.; Perali, A.; Hamilton, A.R.; Partoens, B.; Peeters, F.M.; Neilson, D. |
Title |
Three-dimensional electron-hole superfluidity in a superlattice close to room temperature |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
Volume |
102 |
Issue |
6 |
Pages |
060503 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Although there is strong theoretical and experimental evidence for electron-hole superfluidity in separated sheets of electrons and holes at low T, extending superfluidity to high T is limited by strong two-dimensional fluctuations and Kosterlitz-Thouless effects. We show this limitation can be overcome using a superlattice of alternating electron- and hole-doped semiconductor monolayers. The superfluid transition in a three-dimensional superlattice is not topological, and for strong electron-hole pair coupling, the transition temperature T-c can be at room temperature. As a quantitative illustration, we show T-c can reach 270 K for a superfluid in a realistic superlattice of transition metal dichalcogenide monolayers. |
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Editor |
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Wos |
000562320700001 |
Publication Date |
2020-08-25 |
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 |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.7 |
Times cited |
8 |
Open Access |
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Notes |
; This work was supported by the Research Foundation of Flanders (FWO-Vl) through an aspirant research grant for M.V.d.D., by the FLAG-ERA project TRANS-2D-TMD, and by the Australian Government through the Australian Research Council Centre of Excellence in Future Low-Energy Electronics (Project No. CE170100039). We thank Milorad V. Milossevi ' c, Pierbiagio Pieri, and Jacques Tempere for helpful discussions. ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
Call Number |
UA @ admin @ c:irua:172064 |
Serial |
6628 |
Permanent link to this record |