| Records |
| Author |
Wang, F.; Wang, C.; Chaves, A.; Song, C.; Zhang, G.; Huang, S.; Lei, Y.; Xing, Q.; Mu, L.; Xie, Y.; Yan, H. |
| Title |
Prediction of hyperbolic exciton-polaritons in monolayer black phosphorus |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Nature Communications |
Abbreviated Journal |
Nat Commun |
| Volume |
12 |
Issue |
1 |
Pages |
5628 |
Keywords  |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
Hyperbolic polaritons exhibit large photonic density of states and can be collimated in certain propagation directions. The majority of hyperbolic polaritons are sustained in man-made metamaterials. However, natural-occurring hyperbolic materials also exist. Particularly, natural in-plane hyperbolic polaritons in layered materials have been demonstrated in MoO3 and WTe2, which are based on phonon and plasmon resonances respectively. Here, by determining the anisotropic optical conductivity (dielectric function) through optical spectroscopy, we predict that monolayer black phosphorus naturally hosts hyperbolic exciton-polaritons due to the pronounced in-plane anisotropy and strong exciton resonances. We simultaneously observe a strong and sharp ground state exciton peak and weaker excited states in high quality monolayer samples in the reflection spectrum, which enables us to determine the exciton binding energy of similar to 452 meV. Our work provides another appealing platform for the in-plane natural hyperbolic polaritons, which is based on excitons rather than phonons or plasmons. |
| 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 |
000698984500003 |
Publication Date |
2021-10-12 |
| 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 |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
12.124 |
Times cited |
|
Open Access |
Not_Open_Access |
| Notes |
|
Approved |
Most recent IF: 12.124 |
| Call Number |
UA @ admin @ c:irua:191688 |
Serial |
8404 |
| Permanent link to this record |
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| |
| Author |
Xiang, F.; Gupta, A.; Chaves, A.; Krix, Z.E.; Watanabe, K.; Taniguchi, T.; Fuhrer, M.S.; Peeters, F.M.; Neilson, D.; Milošević, M.V.; Hamilton, A.R. |
| Title |
Intra-zero-energy Landau level crossings in bilayer graphene at high electric fields |
Type |
A1 Journal article |
| Year |
2023 |
Publication |
Nano letters |
Abbreviated Journal |
|
| Volume |
23 |
Issue |
21 |
Pages |
9683-9689 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
The highly tunable band structure of the zero-energy Landau level (zLL) of bilayer graphene makes it an ideal platform for engineering novel quantum states. However, the zero-energy Landau level at high electric fields has remained largely unexplored. Here we present magnetotransport measurements of bilayer graphene in high transverse electric fields. We observe previously undetected Landau level crossings at filling factors nu = -2, 1, and 3 at high electric fields. These crossings provide constraints for theoretical models of the zero-energy Landau level and show that the orbital, valley, and spin character of the quantum Hall states at high electric fields is very different from low electric fields. At high E, new transitions between states at nu = -2 with different orbital and spin polarization can be controlled by the gate bias, while the transitions between nu = 0 -> 1 and nu = 2 -> 3 show anomalous behavior. |
| 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 |
001102148900001 |
Publication Date |
2023-10-26 |
| 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 |
1530-6984 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
10.8 |
Times cited |
1 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 10.8; 2023 IF: 12.712 |
| Call Number |
UA @ admin @ c:irua:201200 |
Serial |
9052 |
| Permanent link to this record |
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| Author |
Tran, T.T.; Lee, Y.; Roy, S.; Tran, T.U.; Kim, Y.; Taniguchi, T.; Watanabe, K.; Milošević, M.V.; Lim, S.C.; Chaves, A.; Jang, J.I.; Kim, J. |
| Title |
Synergetic enhancement of quantum yield and exciton lifetime of monolayer WS₂ by proximal metal plate and negative electric bias |
Type |
A1 Journal article |
| Year |
2023 |
Publication |
ACS nano |
Abbreviated Journal |
|
| Volume |
18 |
Issue |
1 |
Pages |
220-228 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
The efficiency of light emission is a critical performance factor for monolayer transition metal dichalcogenides (1L-TMDs) for photonic applications. While various methods have been studied to compensate for lattice defects to improve the quantum yield (QY) of 1L-TMDs, exciton-exciton annihilation (EEA) is still a major nonradiative decay channel for excitons at high exciton densities. Here, we demonstrate that the combined use of a proximal Au plate and a negative electric gate bias (NEGB) for 1L-WS2 provides a dramatic enhancement of the exciton lifetime at high exciton densities with the corresponding QY enhanced by 30 times and the EEA rate constant decreased by 80 times. The suppression of EEA by NEGB is attributed to the reduction of the defect-assisted EEA process, which we also explain with our theoretical model. Our results provide a synergetic solution to cope with EEA to realize high-intensity 2D light emitters using TMDs. |
| 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 |
001139516800001 |
Publication Date |
2023-12-21 |
| 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 |
1936-0851 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
17.1 |
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 17.1; 2023 IF: 13.942 |
| Call Number |
UA @ admin @ c:irua:202811 |
Serial |
9101 |
| Permanent link to this record |
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| Author |
Conti, S.; Chaves, A.; Pandey, T.; Covaci, L.; Peeters, F.M.; Neilson, D.; Milošević, M.V. |
| Title |
Flattening conduction and valence bands for interlayer excitons in a moire MoS₂/WSe₂ heterobilayer |
Type |
A1 Journal article |
| Year |
2023 |
Publication |
Nanoscale |
Abbreviated Journal |
|
| Volume |
|
Issue |
|
Pages |
1-11 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
| Abstract |
We explore the flatness of conduction and valence bands of interlayer excitons in MoS2/WSe2 van der Waals heterobilayers, tuned by interlayer twist angle, pressure, and external electric field. We employ an efficient continuum model where the moire pattern from lattice mismatch and/or twisting is represented by an equivalent mesoscopic periodic potential. We demonstrate that the mismatch moire potential is too weak to produce significant flattening. Moreover, we draw attention to the fact that the quasi-particle effective masses around the Gamma-point and the band flattening are reduced with twisting. As an alternative approach, we show (i) that reducing the interlayer distance by uniform vertical pressure can significantly increase the effective mass of the moire hole, and (ii) that the moire depth and its band flattening effects are strongly enhanced by accessible electric gating fields perpendicular to the heterobilayer, with resulting electron and hole effective masses increased by more than an order of magnitude – leading to record-flat bands. These findings impose boundaries on the commonly generalized benefits of moire twistronics, while also revealing alternative feasible routes to achieve truly flat electron and hole bands to carry us to strongly correlated excitonic phenomena on demand. |
| 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 |
001047512300001 |
Publication Date |
2023-07-25 |
| 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 |
2040-3364; 2040-3372 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.7 |
Times cited |
1 |
Open Access |
Not_Open_Access: Available from 25.01.2024 |
| Notes |
|
Approved |
Most recent IF: 6.7; 2023 IF: 7.367 |
| Call Number |
UA @ admin @ c:irua:198290 |
Serial |
8819 |
| Permanent link to this record |
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| |
| Author |
Chaves, A.; Neilson, D. |
| Title |
Exotic state seen at high temperatures |
Type |
Editorial |
| Year |
2019 |
Publication |
Nature |
Abbreviated Journal |
Nature |
| Volume |
574 |
Issue |
7776 |
Pages |
39-40 |
| Keywords |
Editorial; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
The phenomenon of Bose-Einstein condensation is typically limited to extremely low temperatures. The effect has now been spotted at much higher temperatures for particles called excitons in atomically thin semiconductors. |
| 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 |
000488832500022 |
Publication Date |
2019-10-02 |
| 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 |
0028-0836 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
40.137 |
Times cited |
2 |
Open Access |
|
| Notes |
; ; |
Approved |
Most recent IF: 40.137 |
| Call Number |
UA @ admin @ c:irua:163739 |
Serial |
5413 |
| Permanent link to this record |
