| Records |
| Author |
Kong, X.; Li, L.; Peeters, F.M. |
| Title |
Graphene-based heterostructures with moire superlattice that preserve the Dirac cone: a first-principles study |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
| Volume |
31 |
Issue |
25 |
Pages |
255302 |
Keywords  |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
In van der Waals heterostructures consisting of graphene and a substrate, lattice mismatch often leads to a moire pattern with a huge supercell, preventing its treatment within first- principles calculations. Previous theoretical works considered mostly simple stacking models such as AB, AA with straining the lattice of graphene to match that of the substrate. Here, we propose a moire superlattice build from graphene and porous graphene or graphyne like monolayers, having a lower interlayer binding energy, needing little strain in order to match the lattices. In contrast to the results from the simple stacking models, the present ab initio calculations for the moire superlattices show different properties in lattice structure, energy, and band structures. For example, the Dirac cone at the K point is preserved and a linear energy dispersion near the Fermi level is obtained. |
| 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 |
000464184300001 |
Publication Date |
2019-03-25 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.649 |
Times cited |
4 |
Open Access |
|
| Notes |
; This work is supported by the Collaborative Innovation Center of Quantum Matter, the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl) and the FLAG-ERA project TRANS-2D-TMD. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation-Flanders (FWO) and the Flemish Government-department EWI, and the National Supercomputing Center in Tianjin, funded by the Collaborative Innovation Center of Quantum Matter. ; |
Approved |
Most recent IF: 2.649 |
| Call Number |
UA @ admin @ c:irua:159314 |
Serial |
5215 |
| Permanent link to this record |
| |
|
| |
| Author |
Li, L.; Kong, X.; Peeters, F.M. |
| Title |
New nanoporous graphyne monolayer as nodal line semimetal : double Dirac points with an ultrahigh Fermi velocity |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| Volume |
141 |
Issue |
141 |
Pages |
712-718 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Two-dimensional (2D) carbon materials play an important role in nanomaterials. We propose a new carbon monolayer, named hexagonal-4,4,4-graphyne (H-4,H-4,H-4-graphyne), which is a nanoporous structure composed of rectangular carbon rings and triple bonds of carbon. Using first-principles calculations, we systematically studied the structure, stability, and band structure of this new material. We found that its total energy is lower than that of experimentally synthesized beta-graphdiyne and it is stable at least up to 1500 K. In contrast to the single Dirac point band structure of other 2D carbon monolayers, the band structure of H-4,H-4,H-4-graphyne exhibits double Dirac points along the high-symmetry points and the corresponding Fermi velocities (1.04-1.27 x 10(6) m/s) are asymmetric and higher than that of graphene. The origin of these double Dirac points is traced back to the nodal line states, which can be well explained by a tight-binding model. The H-4,H-4,H-4-graphyne forms a moire superstructure when placed on top of a hexagonal boron nitride substrate. These properties make H-4,H-4,H-4-graphyne a promising semimetal material for applications in high-speed electronic devices. (C) 2018 Elsevier Ltd. All rights reserved. |
| 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 |
000450312600072 |
Publication Date |
2018-10-01 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0008-6223 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.337 |
Times cited |
38 |
Open Access |
|
| Notes |
; This work was supported by the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl), and the FLAG-ERA project TRANS2DTMD. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government -department EWI. ; |
Approved |
Most recent IF: 6.337 |
| Call Number |
UA @ admin @ c:irua:155364 |
Serial |
5222 |
| Permanent link to this record |
| |
|
| |
| Author |
Wang, W.; Li, L.; Kong, X.; Van Duppen, B.; Peeters, F.M. |
| Title |
T4,4,4-graphyne : a 2D carbon allotrope with an intrinsic direct bandgap |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Solid state communications |
Abbreviated Journal |
Solid State Commun |
| Volume |
293 |
Issue |
293 |
Pages |
23-27 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
A novel two-dimensional (2D) structurally stable carbon allotrope is proposed using first-principles calculations, which is a promising material for water purification and for electronic devices due to its unique porous structure and electronic properties. Rectangular and hexagonal rings are connected with acetylenic linkages, forming a nanoporous structure with a pore size of 6.41 angstrom, which is known as T-4,T-4,T-4-graphyne. This 2D sheet exhibits a direct bandgap of 0.63 eV at the M point, which originates from the p(z)( )atomic orbitals of carbon atoms as confirmed by a tight-binding model. Importantly, T-4,T-4,T-4-graphyne is found to be energetically more preferable than the experimentally realized beta-graphdiyne, it is dynamically stable and can withstand temperatures up to 1500 K. |
| 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 |
|
Wos |
000460909600005 |
Publication Date |
2019-02-10 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0038-1098 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.554 |
Times cited |
10 |
Open Access |
|
| Notes |
; This work was supported by National Natural Science Foundation of China (Grant Nos. 11404214 and 11455015), the China Scholarship Council (CSC), the Science and Technology Research Foundation of Jiangxi Provincial Education Department (Grant Nos. GJJ180868 and GJJ161062) the Fonds Wetenschappelijk Onderzoek (FWO-V1), and the FLAG-ERA project TRANS2DTMD. BVD was supported by the Research Foundation – Flanders (FWO-V1) through a postdoctoral fellowship. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation – Flanders (FWO) and the Flemish Government department EWI. ; |
Approved |
Most recent IF: 1.554 |
| Call Number |
UA @ admin @ c:irua:158503 |
Serial |
5234 |
| Permanent link to this record |
| |
|
| |
| Author |
Chen, Q.; Li, L.L.; Peeters, F.M. |
| Title |
Inner and outer ring states of MoS2 quantum rings : energy spectrum, charge and spin currents |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| Volume |
125 |
Issue |
24 |
Pages |
244303 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We investigate the energy levels and persistent currents of MoS2 quantum rings having different shapes and edge types in the presence of a perpendicular magnetic field by means of the tight-binding approach. We find states localized at the inner and outer boundaries of the ring. These energy levels exhibit different magnetic field dependences for the inner and outer ring states due to their different localization properties. They both exhibit the usual Aharanov-Bohm oscillations but with different oscillation periods. In the presence of spin-orbit coupling, we show distinct spin and charge persistent currents for inner and outer ring states. We find well-defined spin currents with negligibly small charge currents. This is because the local currents of spin-up and -down states flow in opposite directions. |
| Address |
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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 |
|
| Language |
|
Wos |
000474439600026 |
Publication Date |
2019-06-25 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.068 |
Times cited |
10 |
Open Access |
|
| Notes |
; This work was supported by the Hunan Provincial Natural Science Foundation of China (Nos. 2015JJ2040, 2018JJ2080, and 2018JJ4047), the National Natural Science Foundation of China (NNSFC) (No. 51502087), the Scientific Research Fund of Hunan Provincial Education Department (Nos. 15A042, 15B056, and 17B060), and the Flemish Science Foundation (FWO-VI). ; |
Approved |
Most recent IF: 2.068 |
| Call Number |
UA @ admin @ c:irua:161309 |
Serial |
5417 |
| Permanent link to this record |
| |
|
| |
| Author |
Li, L.L.; Peeters, F.M. |
| Title |
Strain engineered linear dichroism and Faraday rotation in few-layer phosphorene |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
114 |
Issue |
24 |
Pages |
243102 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We investigate theoretically the linear dichroism and the Faraday rotation of strained few-layer phosphorene, where strain is applied uniaxially along the armchair or zigzag direction of the phosphorene lattice. We calculate the optical conductivity tensor of uniaxially strained few-layer phosphorene by means of the Kubo formula within the tight-binding approach. We show that the linear dichroism and the Faraday rotation of few-layer phosphorene can be significantly modulated by the applied strain. The modulation depends strongly on both the magnitude and direction of strain and becomes more pronounced with increasing number of phosphorene layers. Our results are relevant for mechano-optoelectronic applications based on optical absorption and Hall effects in strained few-layer phosphorene. |
| 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 |
000472599100029 |
Publication Date |
2019-06-17 |
| Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.411 |
Times cited |
11 |
Open Access |
|
| Notes |
; This work was financially supported by the Flemish Science Foundation (FWO-Vl) and by the FLAG-ERA Project TRANS-2D-TMD. ; |
Approved |
Most recent IF: 3.411 |
| Call Number |
UA @ admin @ c:irua:161327 |
Serial |
5428 |
| Permanent link to this record |
| |
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| |
| Author |
Li, L.; Kong, X.; Chen, X.; Li, J.; Sanyal, B.; Peeters, F.M. |
| Title |
Monolayer 1T-LaN₂ : Dirac spin-gapless semiconductor of p-state and Chern insulator with a high Chern number |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Applied Physics Letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
117 |
Issue |
14 |
Pages |
143101 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Two-dimensional transition-metal dinitrides have attracted considerable attention in recent years due to their rich magnetic properties. Here, we focus on rare-earth-metal elements and propose a monolayer of lanthanum dinitride with a 1T structural phase, 1T-LaN2. Using first-principles calculations, we systematically investigated the structure, stability, magnetism, and band structure of this material. It is a flexible and stable monolayer exhibiting a low lattice thermal conductivity, which is promising for future thermoelectric devices. The monolayer shows the ferromagnetic ground state with a spin-polarized band structure. Two linear spin-polarized bands cross at the Fermi level forming a Dirac point, which is formed by the p atomic orbitals of the N atoms, indicating that monolayer 1T-LaN2 is a Dirac spin-gapless semiconductor of p-state. When the spin-orbit coupling is taken into account, a large nontrivial indirect bandgap (86/354meV) can be opened at the Dirac point, and three chiral edge states are obtained, corresponding to a high Chern number of C=3, implying that monolayer 1T-LaN2 is a Chern insulator. Importantly, this kind of band structure is expected to occur in more monolayers of rare-earth-metal dinitride with a 1T structural phase. |
| 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 |
000578551800001 |
Publication Date |
2020-10-06 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4 |
Times cited |
13 |
Open Access |
|
| Notes |
; This work was supported by the Natural Science Foundation of Hebei Province (Grant No. A2020202031), the FLAG-ERA project TRANS2DTMD, the Swedish Research Council project grant (No. 2016-05366), and the Swedish Research Links program grant (No. 2017-05447). The resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation-Flanders (FWO) and the Flemish Government, and Swedish National Infrastructure for Computing (SNIC). A portion of this research (Xiangru Kong) was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. Xin Chen thanks the China scholarship council for financial support from the China Scholarship Council (CSC, No. 201606220031). ; |
Approved |
Most recent IF: 4; 2020 IF: 3.411 |
| Call Number |
UA @ admin @ c:irua:172674 |
Serial |
6564 |
| Permanent link to this record |
| |
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| |
| Author |
Chen, X.; Bouhon, A.; Li, L.; Peeters, F.M.; Sanyal, B. |
| Title |
PAI-graphene : a new topological semimetallic two-dimensional carbon allotrope with highly tunable anisotropic Dirac cones |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| Volume |
170 |
Issue |
|
Pages |
477-486 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Using evolutionary algorithm for crystal structure prediction, we present a new stable two-dimensional (2D) carbon allotrope composed of polymerized as-indacenes (PAI) in a zigzag pattern, namely PAI-graphene whose energy is lower than most of the reported 2D allotropes of graphene. Crucially, the crystal structure realizes a nonsymmorphic layer group that enforces a nontrivial global topology of the band structure with two Dirac cones lying perfectly at the Fermi level. The absence of electron/hole pockets makes PAI-graphene a pristine crystalline topological semimetal having anisotropic Fermi velocities with a high value of 7.0 x 10(5) m/s. We show that while the semimetallic property of the allotrope is robust against the application of strain, the positions of the Dirac cone and the Fermi velocities can be modified significantly with strain. Moreover, by combining strain along both the x- and y-directions, two band inversions take place at G leading to the annihilation of the Dirac nodes demonstrating the possibility of strain-controlled conversion of a topological semimetal into a semiconductor. Finally we formulate the bulk-boundary correspondence of the topological nodal phase in the form of a generalized Zak-phase argument finding a perfect agreement with the topological edge states computed for different edge-terminations. (C) 2020 The Author(s). Published by Elsevier Ltd. |
| 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 |
000579779800047 |
Publication Date |
2020-08-21 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0008-6223 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
10.9 |
Times cited |
27 |
Open Access |
|
| Notes |
; We thank S. Nahas, for helpful discussions. This work is supported by the project grant (2016e05366) and Swedish Research Links program grant (2017e05447) from the Swedish Research Council, the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl), the FLAG-ERA project TRANS 2D TMD. Linyang Li acknowledges financial support from the Natural Science Foundation of Hebei Province (Grant No. A2020202031). X.C. thanks China scholarship council for financial support (No. 201606220031). X.C. and B.S. acknowledge SNIC-UPPMAX, SNIC-HPC2N, and SNIC-NSC centers under the Swedish National Infrastructure for Computing (SNIC) resources for the allocation of time in high-performance supercomputers. Moreover, supercomputing resources from PRACE DECI-15 project DYNAMAT are gratefully acknowledged. ; |
Approved |
Most recent IF: 10.9; 2020 IF: 6.337 |
| Call Number |
UA @ admin @ c:irua:173513 |
Serial |
6577 |
| Permanent link to this record |
| |
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| |
| Author |
Li, L.L.; Bacaksiz, C.; Nakhaee, M.; Pentcheva, R.; Peeters, F.M.; Yagmurcukardes, M. |
| Title |
Single-layer Janus black arsenic-phosphorus (b-AsP): optical dichroism, anisotropic vibrational, thermal, and elastic properties |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
101 |
Issue |
13 |
Pages |
134102-134109 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
By using density functional theory (DFT) calculations, we predict a puckered, dynamically stable Janus single-layer black arsenic-phosphorus (b-AsP), which is composed of two different atomic sublayers, arsenic and phosphorus atoms. The calculated phonon spectrum reveals that Janus single-layer b-AsP is dynamically stable with either pure or coupled optical phonon branches arising from As and P atoms. The calculated Raman spectrum indicates that due to the relatively strong P-P bonds, As atoms have no contribution to the highfrequency optical vibrations. In addition, the orientation-dependent isovolume heat capacity reveals anisotropic contributions of LA and TA phonon branches to the low-temperature thermal properties. Unlike pristine single layers of b-As and b-P, Janus single-layer b-AsP exhibits additional out-of-plane asymmetry which leads to important consequences for its electronic, optical, and elastic properties. In contrast to single-layer b-As, Janus single-layer b-AsP is found to possess a direct band gap dominated by the P atoms. Moreover, real and imaginary parts of the dynamical dielectric function, including excitonic effects, reveal the highly anisotropic optical feature of the Janus single-layer. A tight-binding (TB) model is also presented for Janus single-layer b-AsP, and it is shown that, with up to seven nearest hoppings, the TB model reproduces well the DFT band structure in the low-energy region around the band gap. This TB model can be used in combination with the Green's function approach to study, e.g., quantum transport in finite systems based on Janus single-layer b-AsP. Furthermore, the linear-elastic properties of Janus single-layer b-AsP are investigated, and the orientation-dependent in-plane stiffness and Poisson ratio are calculated. It is found that the Janus single layer exhibits strong in-plane anisotropy in its Poisson ratio much larger than that of single-layer b-P. This Janus single layer is relevant for promising applications in optical dichroism and anisotropic nanoelasticity. |
| 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 |
000524531900001 |
Publication Date |
2020-04-09 |
| 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 |
30 |
Open Access |
|
| Notes |
; This work was supported by the German Science Foundation (DFG) within SFB/TRR80 (project G3) and the FLAGERA project TRANS-2D-TMD. M.Y. was supported by a postdoctoral fellowship from the Flemish Science Foundation (FWO-Vl). Computational resources were provided by the Flemish Supercomputer Center (VSC) and Leibniz Supercomputer Centrum (project pr87ro). ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:168554 |
Serial |
6602 |
| Permanent link to this record |
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| |
| Author |
Dong, H.M.; Tao, Z.H.; Li, L.L.; Huang, F.; Xu, W.; Peeters, F.M. |
| Title |
Substrate dependent terahertz response of monolayer WS₂ |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Applied Physics Letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
116 |
Issue |
20 |
Pages |
1-4 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We investigate experimentally the terahertz (THz) optoelectronic properties of monolayer (ML) tungsten disulfide (WS2) placed on different substrates using THz time-domain spectroscopy (TDS). We find that the THz optical response of n-type ML WS2 depends sensitively on the choice of the substrate. This dependence is found to be a consequence of substrate induced charge transfer, extra scattering centers, and electronic localization. Through fitting the experimental results with the Drude-Smith formula, we can determine the key sample parameters (e.g., the electronic relaxation time, electron density, and electronic localization factor) of ML WS2 on different substrates. The temperature dependence of these parameters is examined. Our results show that the THz TDS technique is an efficient non-contact method that can be utilized to characterize and investigate the optoelectronic properties of nano-devices based on ML WS2. |
| 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 |
000536282300001 |
Publication Date |
2020-05-20 |
| 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 |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4 |
Times cited |
10 |
Open Access |
|
| Notes |
; This work was supported by the Fundamental Research Funds for the Central Universities (Grant No. 2018GF09) and by the National Natural Science foundation of China (Nos. U1930116 and 11574319). ; |
Approved |
Most recent IF: 4; 2020 IF: 3.411 |
| Call Number |
UA @ admin @ c:irua:170255 |
Serial |
6620 |
| Permanent link to this record |
| |
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| |
| Author |
Kong, X.; Li, L.; Liang, L.; Peeters, F.M.; Liu, X.-J. |
| Title |
The magnetic, electronic, and light-induced topological properties in two-dimensional hexagonal FeX₂ (X=Cl, Br, I) monolayers |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Applied Physics Letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
116 |
Issue |
19 |
Pages |
192404-192405 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Using Floquet-Bloch theory, we propose to realize chiral topological phases in two-dimensional (2D) hexagonal FeX2 (X=Cl, Br, I) monolayers under irradiation of circularly polarized light. Such 2D FeX2 monolayers are predicted to be dynamically stable and exhibit both ferromagnetic and semiconducting properties. To capture the full topological physics of the magnetic semiconductor under periodic driving, we adopt ab initio Wannier-based tight-binding methods for the Floquet-Bloch bands, with the light-induced bandgap closings and openings being obtained as the light field strength increases. The calculations of slabs with open boundaries show the existence of chiral edge states. Interestingly, the topological transitions with branches of chiral edge states changing from zero to one and from one to two by tuning the light amplitude are obtained, showing that the topological Floquet phase of high Chern number can be induced in the present Floquet-Bloch systems. 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 |
000533500900001 |
Publication Date |
2020-05-11 |
| 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 |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4 |
Times cited |
13 |
Open Access |
|
| Notes |
; This work was supported by the Ministry of Science and Technology of China (MOST) (Grant No. 2016YFA0301604), the National Natural Science Foundation of China (NSFC) (Nos. 11574008, 11761161003, 11825401, and 11921005), the Strategic Priority Research Program of Chinese Academy of Science (Grant No. XDB28000000), the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl), and the FLAG-ERA Project TRANS 2D TMD. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation-Flanders (FWO) and the Flemish Government-Department EWI-and the National Supercomputing Center in Tianjin, funded by the Collaborative Innovation Center of Quantum Matter. This research also used resources of the Compute and Data Environment for Science (CADES) at the Oak Ridge National Laboratory, which was supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725. X.K. and L.L. also acknowledge the work conducted at the Center for Nanophase Materials Sciences, which is a U.S. Department of Energy Office of Science User Facility. ; |
Approved |
Most recent IF: 4; 2020 IF: 3.411 |
| Call Number |
UA @ admin @ c:irua:169496 |
Serial |
6623 |
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| Author |
Chen, X.; Li, L.; Peeters, F.M.; Sanyal, B. |
| Title |
Two-dimensional oxygen functionalized honeycomb and zigzag dumbbell silicene with robust Dirac cones |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
New Journal Of Physics |
Abbreviated Journal |
New J Phys |
| Volume |
23 |
Issue |
2 |
Pages |
023007 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Dumbbell-like structures are recently found to be energetically favored in group IV two-dimensional (2D) materials, exhibiting rich physics and many interesting properties. In this paper, using first-principles calculations, we have investigated the oxidized form of the hexagonal honeycomb (ODB-h) and zigzag dumbbell silicene (ODB-z). We confirm that both oxidization processes are energetically favorable, and their phonon spectra further demonstrate the dynamic stability. Contrary to the pristine dumbbell silicene structures (PDB-h and PDB-z silicene), these oxidized products ODB-h and ODB-z silicene are both semimetals with Dirac cones at the Fermi level. The Dirac cones of ODB-h and ODB-z silicene are at the K point and between Y and Gamma points respectively, possessing high Fermi velocities of 3.1 x 10(5) m s(-1) (ODB-h) and 2.9-3.4 x 10(5) m s(-1) (ODB-z). The origin of the Dirac cones is further explained by tight-binding models. The semimetallic properties of ODB-h and ODB-z are sensitive to compression due to the self-absorption effect, but quite robust against the tensile strain. These outstanding properties make oxidized dumbbell silicene a promising material for quantum computing and high-speed electronic devices. |
| 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 |
000616114900001 |
Publication Date |
2021-01-14 |
| 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 |
1367-2630 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.786 |
Times cited |
1 |
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 3.786 |
| Call Number |
UA @ admin @ c:irua:176575 |
Serial |
6741 |
| Permanent link to this record |
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| Author |
Yu, Y.; Chen, X.; Liu, X.; Li, J.; Sanyal, B.; Kong, X.; Peeters, F.M.; Li, L. |
| Title |
Ferromagnetism with in-plane magnetization, Dirac spin-gapless semiconducting properties, and tunable topological states in two-dimensional rare-earth metal dinitrides |
Type |
A1 Journal article |
| Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
105 |
Issue |
2 |
Pages |
024407 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Since the successful synthesis of bulk single crystals MoN2 and ReN2, which have a layered structure, transition-metal dinitrides have attracted considerable attention in recent years. Here, we focus on rare-earth metal (Rem) elements, and propose seven stable Rem dinitride monolayers with a 1T structure, namely, 1T-RemN2. We use first-principles calculations, and find that these monolayers have a ferromagnetic ground state with in-plane magnetization. Without spin-orbit coupling (SOC), the band structures are spin-polarized with Dirac points at the Fermi level. Remarkably, the 1T-LuN2 monolayer exhibits an isotropic magnetocrystalline anisotropy energy in the xy plane with in-plane magnetization, indicating easy tunability of the magnetization direction. When rotating the magnetization vector in the xy plane, we propose a model that accurately describes the variation of the SOC band gap and the two possible topological states (Weyl-like semimetal and Chern insulator states) whose properties are tunable. The Weyl-like semimetal state is a critical point between the two Chern insulator states with opposite sign of the Chern numbers (+/- 1). The nontrivial band gap (up to 60.3 meV) and the Weyl-like semimetal state are promising for applications in spintronic devices. |
| 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 |
000742384700001 |
Publication Date |
2022-01-06 |
| 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 |
3.7 |
Times cited |
4 |
Open Access |
Not_Open_Access: Available from 06.07.2202 |
| Notes |
|
Approved |
Most recent IF: 3.7 |
| Call Number |
UA @ admin @ c:irua:186514 |
Serial |
6991 |
| Permanent link to this record |
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| Author |
Dong, H.M.; Tao, Z.H.; Duan, Y.F.; Li, L.L.; Huang, F.; Peeters, F.M. |
| Title |
Substrate dependent terahertz magneto-optical properties of monolayer WS2 |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Optics Letters |
Abbreviated Journal |
Opt Lett |
| Volume |
46 |
Issue |
19 |
Pages |
4892-4895 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Terahertz (THz) magneto-optical (MO) properties of monolayer (ML) tungsten disulfide (WS2), placed on different substrates and subjected to external magnetic fields, are studied using THz time-domain spectroscopy (TDS). We find that the THz MO conductivity exhibits a nearly linear response in a weak magnetic field, while a distinctly nonlinear/oscillating behavior is found in strong magnetic fields owing to strong substrate-induced random impurity scattering and interactions. The THz MO response of ML WS2 depends sensitively on the choice of the substrates, which we trace back to electronic localization and the impact of the substrates on the Landau level (LL) spectrum. Our results provide an in-depth understanding of the THz MO properties of ML WS2/substrate systems, especially the effect of substrates, which can be utilized to realize atomically thin THz MO nano-devices. (C) 2021 Optical Society of America |
| 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 |
000702746400048 |
Publication Date |
2021-09-01 |
| Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0146-9592 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
3.416 |
Times cited |
1 |
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 3.416 |
| Call Number |
UA @ admin @ c:irua:182526 |
Serial |
7023 |
| Permanent link to this record |
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| Author |
Yu, Y.; Xie, X.; Liu, X.; Li, J.; Peeters, F.M.; Li, L. |
| Title |
Two-dimensional semimetal states in transition metal trichlorides : a first-principles study |
Type |
A1 Journal article |
| Year |
2022 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
121 |
Issue |
11 |
Pages |
112405-112407 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The two-dimensional (2D) transition metal trihalide (TMX3, X = Cl, Br, I) family has attracted considerable attention in recent years due to the realization of CrCl3, CrBr3, and CrI3 monolayers. Up to now, the main focus of the theoretically predicted TMX3 monolayers has been on the Chern insulator states, which can realize the quantum anomalous Hall effect. Here, using first-principles calculations, we theoretically demonstrate that the stable OsCl3 monolayer has a ferromagnetic ground state and a spin-polarized Dirac point without spin-orbit coupling (SOC), which disappears in the band structure of a Janus OsBr1.5Cl1.5 monolayer. We find that OsCl3 exhibits in-plane magnetization when SOC is included. By manipulating the magnetization direction along the C-2 symmetry axis of the OsCl3 structure, a gapless half-Dirac semimetal state with SOC can be achieved, which is different from the gapped Chern insulator state. Both semimetal states of OsCl3 monolayer without and with SOC exhibit a linear half-Dirac point (twofold degenerate) with high Fermi velocities. The achievement of the 2D semimetal state with SOC is expected to be found in other TMX3 monolayers, and we confirm it in a TiCl3 monolayer. This provides a different perspective to study the band structure with SOC of the 2D TMX3 family. |
| 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 |
000863219400003 |
Publication Date |
2022-09-15 |
| 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 |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
4 |
Times cited |
|
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 4 |
| Call Number |
UA @ admin @ c:irua:191541 |
Serial |
7223 |
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| Author |
Li, L.L.; Gillen, R.; Palummo, M.; Milošević, M.V.; Peeters, F.M. |
| Title |
Strain tunable interlayer and intralayer excitons in vertically stacked MoSe₂/WSe₂ heterobilayers |
Type |
A1 Journal article |
| Year |
2023 |
Publication |
Applied physics letters |
Abbreviated Journal |
|
| Volume |
123 |
Issue |
3 |
Pages |
033102-33106 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Recently, interlayer and intralayer excitons in transition metal dichalcogenide heterobilayers have been studied both experimentally and theoretically. In spite of a growing interest, these layer-resolved excitons in the presence of external stimuli, such as strain, remain not fully understood. Here, using density-functional theory calculations with many-body effects, we explore the excitonic properties of vertically stacked MoSe2/WSe2 heterobilayer in the presence of in-plane biaxial strain of up to 5%. We calculate the strain dependence of exciton absorption spectrum, oscillator strength, wave function, and binding energy by solving the Bethe-Salpeter equation on top of the standard GW approach. We identify the interlayer and intralayer excitons by analyzing their electron-hole weights and spatial wave functions. We show that with the increase in strain magnitude, the absorption spectrum of the interlayer and intralayer excitons is red-shifted and re-ordered, and the binding energies of these layer-resolved excitons decrease monotonically and almost linearly. We derive the sensitivity of exciton binding energy to the applied strain and find that the intralayer excitons are more sensitive to strain than the interlayer excitons. For instance, a sensitivity of -7.9 meV/% is derived for the intra-MoSe2-layer excitons, which is followed by -7.4 meV/% for the intra-WSe2-layer excitons, and by -4.2 meV/% for the interlayer excitons. Our results indicate that interlayer and intralayer excitons in vertically stacked MoSe2/WSe2 heterobilayer are efficiently tunable by in-plane biaxial strain. |
| 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 |
001033604700003 |
Publication Date |
2023-07-20 |
| 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 |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4 |
Times cited |
|
Open Access |
OpenAccess |
| Notes |
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Approved |
Most recent IF: 4; 2023 IF: 3.411 |
| Call Number |
UA @ admin @ c:irua:198382 |
Serial |
8823 |
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| Author |
Basile, F.; Benito, P.; Bugani, S.; de Nolf, W.; Fornasari, G.; Janssens, K.; Morselli, L.; Scavetta, E.; Tonelli, D.; Vaccari, A. |
| Title |
Combined use of synchrotron-radiation-based imaging techniques for the characterization of structured catalysts |
Type |
A1 Journal article |
| Year |
2010 |
Publication |
Advanced functional materials |
Abbreviated Journal |
Adv Funct Mater |
| Volume |
20 |
Issue |
23 |
Pages |
4117-4126 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
Active-phase-coated metallic supports as structured catalysts are gaining attention in endothermic and exothermic processes because they improve heat transfer. The deposition of a well-adhered and stable catalyst layer on the metallic support constitutes an important feature for the successful application of the final material. In this work, coating of FeCrAlY foams is performed by a one-step electrosynthesis-deposition of hydrotalcite-type compounds, precursors of catalysts active in endothermic steam methane reforming. The catalysts are studied at different length scales by using, for the first time, a combination of several techniques: SEM/EDS and X-ray fluorescence, X-ray powder diffraction and absorption-tomography experiments on the micro- and nanoscales at a synchrotron facility. The results show that the morphology of the coating depends on the synthesis conditions and that the catalyst may be described as Ni metal crystallites dispersed on γ-Al2O3, homogeneously coating the FeCrAlY foam. |
| Address |
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Thesis |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000285392900010 |
Publication Date |
2010-09-23 |
| 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 |
1616-301x |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
12.124 |
Times cited |
24 |
Open Access |
|
| Notes |
; The authors give thanks to Dr. Cloetens, for helping during the absorption tomography experiments, performed at ID19 of the ESRF; and P. Blauet and R. Toucolou, for helping during the mu-XRF/XRPD and nano-XRF experiments at ID22 and ID22-NI of the ESRF. The financial support from the Ministero per l'Istruzione, l'Universita e la Ricerca (MIUR, Roma, Italy) is gratefully acknowledged. ; |
Approved |
Most recent IF: 12.124; 2010 IF: 8.508 |
| Call Number |
UA @ admin @ c:irua:85834 |
Serial |
5525 |
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| Author |
Bugani, S.; Modugno, F.; Lucejko, J.J.; Giachi, G.; Cagno, S.; Cloetens, P.; Janssens, K.; Morselli, L. |
| Title |
Study on the impregnation of archaeological waterlogged wood with consolidation treatments using synchrotron radiation microtomography |
Type |
A1 Journal article |
| Year |
2009 |
Publication |
Analytical and bioanalytical chemistry |
Abbreviated Journal |
Anal Bioanal Chem |
| Volume |
395 |
Issue |
7 |
Pages |
1977-1985 |
| Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
| Abstract |
In favourable conditions of low temperature and low oxygen concentration, archaeological waterlogged wooden artefacts, such as shipwrecks, can survive with a good state of preservation. Nevertheless, anaerobic bacteria can considerably degrade waterlogged wooden objects with a significant loss in polysaccharidic components. Due to these decay processes, wood porosity and water content increase under ageing. In such conditions, the conservation treatments of archaeological wooden artefacts often involve the replacement of water with substances which fill the cavities and help to prevent collapse and stress during drying. The treatments are very often expensive and technically difficult, and their effectiveness very much depends on the chemical and physical characteristics of the substances used for impregnation. Also important are the degree of cavity-filling, penetration depth and distribution in the structure of the wood. In this study, the distribution in wood cavities of some mixtures based on polyethylene glycols and colophony, used for the conservation of waterlogged archaeological wood, was investigated using synchrotron radiation X-ray computed microtomography (SR-A mu CT). This non-destructive imaging technique was useful for the study of the degraded waterlogged wood and enabled us to visualise the morphology of the wood and the distribution of the materials used in the wood treatments. The study has shown how deposition is strictly related to the dimension of the wooden cavities. The work is currently proceeding with the comparison of synchrotron observations with the data of the solutions viscosity and with those of the properties imparted to the wood by the treatments. |
| Address |
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| Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000272017000005 |
Publication Date |
2009-09-16 |
| 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 |
1618-2642 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.431 |
Times cited |
30 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.431; 2009 IF: 3.480 |
| Call Number |
UA @ admin @ c:irua:94493 |
Serial |
5853 |
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| Author |
Li, L.; Nijs, I.; De Boeck, H.; Vinduskova, O.; Reynaert, S.; Donnelly, C.; Zi, L.; Verbruggen, E. |
| Title |
Longer dry and wet spells alter the stochasticity of microbial community assembly in grassland soils |
Type |
A1 Journal article |
| Year |
2023 |
Publication |
Soil biology and biochemistry |
Abbreviated Journal |
|
| Volume |
178 |
Issue |
|
Pages |
108969-9 |
| Keywords |
A1 Journal article; ADReM Data Lab (ADReM); Integrated Molecular Plant Physiology Research (IMPRES); Plant and Ecosystems (PLECO) – Ecology in a time of change |
| Abstract |
Climate change is increasing the duration of alternating wet and dry spells. These fluctuations affect soil water availability and other soil properties which are crucial drivers of soil microbial communities. While soil microbial communities have a moderate capacity to recover once a drought ceases, the expected alternation of strongly opposing regimes can challenge their capacity to adapt. Here, we set up experimental grassland mesocosms where precipitation frequency was adjusted along a gradient while holding total precipitation constant. The gradient varied the duration of wet and dry spells from 1 to 60 days during a total of 120 days, where we hy-pothesized that especially intermediate durations would increase the importance of stochastic community as-sembly due to frequent alternation of opposing environmental regimes. We examined bacterial and fungal community composition, diversity, co-occurrence patterns and assembly mechanisms across these different precipitation treatments. Our results show that 1) intermediate regimes of wet and dry spells increased the stochasticity of microbial community assembly whereas microbial communities at low and high regimes were subjected to more deterministic assembly, and 2) more persistent precipitation regimes (>6 days duration) reduced the fungal diversity and network connectivity but had little effect on bacterial communities. Collec-tively, these findings indicate that longer alternating wet and dry events lead to a less predictable and connected soil microbial community. This study provides new insight into the likely mechanisms through which precipi-tation persistence alters soil microbial communities and their predictability. |
| 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 |
000930582500001 |
Publication Date |
2023-01-28 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
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| ISSN |
0038-0717 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
no |
| Call Number |
UA @ admin @ c:irua:195257 |
Serial |
9211 |
| Permanent link to this record |
