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Author |
Nguyen, H.T.T.; Obeid, M.M.; Bafekry, A.; Idrees, M.; Vu, T.V.; Phuc, H., V; Hieu, N.N.; Le Hoa, T.; Amin, B.; Nguyen, C., V |
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Title |
Interfacial characteristics, Schottky contact, and optical performance of a graphene/Ga2SSe van der Waals heterostructure: Strain engineering and electric field tunability |
Type |
A1 Journal article |
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Year  |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
102 |
Issue |
7 |
Pages |
075414-10 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Two-dimensional graphene-based van der Waals heterostructures have received considerable interest because of their intriguing characteristics compared with the constituent single-layer two-dimensional materials. Here, we investigate the interfacial characteristics, Schottky contact, and optical performance of graphene/Ga2SSe van der Waals (vdW) heterostructure using first-principles calculations. The effects of stacking patterns, electric gating, and interlayer coupling on the interfacial properties of graphene/Ga2SSe heterostructures are also examined. Our results demonstrate that the Dirac cone of graphene is well preserved at the F point in all stacking patterns due to the weak vdW interactions, which keep the heterostructures feasible such that they can be obtained in further experiments. Moreover, depending on the stacking patterns, a small band gap of about 13-17 meV opens in graphene and has a high carrier mobility, indicating that the graphene/Ga2SSe heterostructures are potential candidates for future high-speed nanoelectronic applications. In the ground state, the graphene/Ga2SSe heterostructures form an n-type Schottky contact. The transformation from an n-type to a p-type Schottky contact or to an Ohmic contact can be forced by electric gating or by varying the interlayer coupling. Our findings could provide physical guidance for designing controllable Schottky nanodevices with high electronic and optical performances. |
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Wos |
000557294500006 |
Publication Date |
2020-08-07 |
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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 |
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Impact Factor |
3.7 |
Times cited |
12 |
Open Access |
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Notes |
; This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under Grant No. 103.01-2019.05. The authors declare that there are no conflicts of interest regarding the publication of this paper. ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
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Call Number |
UA @ admin @ c:irua:171163 |
Serial |
6549 |
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Author |
Bekaert, J.; Sevik, C.; Milošević, M.V. |
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Title |
First-principles exploration of superconductivity in MXenes |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
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Volume |
12 |
Issue |
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Pages |
17354-17361 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
MXenes are an emerging class of two-dimensional materials, which in their thinnest limit consist of a monolayer of carbon or nitrogen (X) sandwiched between two transition metal (M) layers. We have systematically searched for superconductivity among MXenes for a range of transition metal elements, based on a full first-principles characterization in combination with the Eliashberg formalism. Thus, we identified six superconducting MXenes: three carbides (Mo2C, W2C and Sc2C) and three nitrides (Mo2N, W2N and Ta2N). The highest critical temperature of similar to 16 K is found in Mo2N, for which a successful synthesis method has been established [Urbankowskiet al.,Nanoscale, 2017,9, 17722-17730]. Moreover, W2N presents a novel case of competing superconducting and charge density wave phases. |
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Wos |
000563481700017 |
Publication Date |
2020-08-07 |
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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 |
2040-3364 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.7 |
Times cited |
15 |
Open Access |
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Notes |
; This work is supported by The Scientific and Technological Research Council of Turkey (TUBITAK) under the contract number COST-118F187, the Air Force Office of Scientific Research under award number FA9550-19-1-7048, by Research Foundation-Flanders (FWO) and the University of Antwerp (BOF). The collaboration was fostered by COST action NANOCOHYBRI (CA16218). Computational resources were provided by the High Performance and Grid Computing Center (TRGrid e-Infrastructure) of TUBITAK ULAKBIM, the National Center for High Performance Computing (UHeM) of Istanbul Technical University, and by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government – department EWI. J. B. acknowledges support of a postdoctoral fellowship of the FWO. ; |
Approved |
Most recent IF: 6.7; 2020 IF: 7.367 |
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Call Number |
UA @ admin @ c:irua:171988 |
Serial |
6521 |
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Author |
Vanherck, J.; Bacaksiz, C.; Sorée, B.; Milošević, M.V.; Magnus, W. |
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Title |
2D ferromagnetism at finite temperatures under quantum scrutiny |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Applied Physics Letters |
Abbreviated Journal |
Appl Phys Lett |
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Volume |
117 |
Issue |
5 |
Pages |
052401 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Recent years have seen a tremendous rise of two-dimensional (2D) magnetic materials, several of which were verified experimentally. However, most of the theoretical predictions to date rely on ab initio methods, at zero temperature and fluctuation-free, while one certainly expects detrimental quantum fluctuations at finite temperatures. Here, we present the solution of the quantum Heisenberg model for honeycomb/hexagonal lattices with anisotropic exchange interaction up to third nearest neighbors and in an applied field in arbitrary direction, which answers the question whether long-range magnetization can indeed survive in the ultrathin limit of materials, up to which temperature, and what the characteristic excitation (magnon) frequencies are, all essential to envisaged applications of magnetic 2D materials. We find that long-range magnetic order persists at finite temperature for materials with overall easy-axis anisotropy. We validate the calculations on the examples of monolayers CrI3, CrBr3, and MnSe2. Moreover, we provide an easy-to-use tool to calculate Curie temperatures of new 2D computational materials. |
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Wos |
000559330100001 |
Publication Date |
2020-08-03 |
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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 |
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Impact Factor |
4 |
Times cited |
8 |
Open Access |
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Notes |
; This work was supported by the Research Foundation-Flanders (FWO) and the special research funds of the University of Antwerp (BOF-UA). ; |
Approved |
Most recent IF: 4; 2020 IF: 3.411 |
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Call Number |
UA @ admin @ c:irua:171176 |
Serial |
6445 |
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Author |
Sabani, D.; Bacaksiz, C.; Milošević, M.V. |
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Title |
Ab initio methodology for magnetic exchange parameters: Generic four-state energy mapping onto a Heisenberg spin Hamiltonian |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
102 |
Issue |
1 |
Pages |
014457-14458 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The recent development in the field of two-dimensional magnetic materials urges reliable theoretical methodology for determination of magnetic properties. Among the available methods, ab initio four-state energy mapping based on density functional theory stands out as a powerful technique to calculate the magnetic exchange interaction in the Heisenberg spin model. Although the required formulas were explained in earlier works, the considered Hamiltonian in those studies always corresponded to the specific case that the off-diagonal part of J matrix is antisymmetric, which may be misleading in other cases. Therefore, using the most general form of the Heisenberg spin Hamiltonian, we here derive the generic formulas. With a proper choice of four different magnetic states, a single formula governs all elements of the exchange interaction matrix for any considered pair of spin sites. |
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Wos |
000554409500002 |
Publication Date |
2020-07-31 |
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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 |
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Impact Factor |
3.7 |
Times cited |
13 |
Open Access |
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Notes |
; This work was supported by the Research Foundation-Flanders (FWO-Vlaanderen) and the Special Research Funds of the University of Antwerp (TOPBOF). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation-Flanders (FWO-Vlaanderen) and the Flemish Government, Department EWI. ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
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Call Number |
UA @ admin @ c:irua:171203 |
Serial |
6448 |
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Author |
Bafekry, A.; Nguyen, C., V; Goudarzi, A.; Ghergherehchi, M.; Shafieirad, M. |
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Title |
Investigation of strain and doping on the electronic properties of single layers of C₆N₆ and C₆N₈: a first principles study |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Rsc Advances |
Abbreviated Journal |
Rsc Adv |
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Volume |
10 |
Issue |
46 |
Pages |
27743-27751 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
In this work, by performing first-principles calculations, we explore the effects of various atom impurities on the electronic and magnetic properties of single layers of C(6)N(6)and C6N8. Our results indicate that atom doping may significantly modify the electronic properties. Surprisingly, doping Cr into a holey site of C(6)N(6)monolayer was found to exhibit a narrow band gap of 125 meV upon compression strain, considering the spin-orbit coupling effect. Also, a C atom doped in C(6)N(8)monolayer shows semi-metal nature under compression strains larger than -2%. Our results propose that Mg or Ca doped into strained C(6)N(6)may exhibit small band gaps in the range of 10-30 meV. In addition, a magnetic-to-nonmagnetic phase transition can occur under large tensile strains in the Ca doped C(6)N(8)monolayer. Our results highlight the electronic properties and magnetism of C(6)N(6)and C(6)N(8)monolayers. Our results show that the electronic properties can be effectively modified by atom doping and mechanical strain, thereby offering new possibilities to tailor the electronic and magnetic properties of C(6)N(6)and C(6)N(8)carbon nitride monolayers. |
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Wos |
000553911800053 |
Publication Date |
2020-07-24 |
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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 |
2046-2069 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.9 |
Times cited |
11 |
Open Access |
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Notes |
; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (NRF-2017R1A2B2011989). ; |
Approved |
Most recent IF: 3.9; 2020 IF: 3.108 |
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Call Number |
UA @ admin @ c:irua:172111 |
Serial |
6553 |
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Author |
Yorulmaz, U.; Demiroglu, I.; Cakir, D.; Gulseren, O.; Sevik, C. |
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Title |
A systematicalab-initioreview of promising 2D MXene monolayers towards Li-ion battery applications |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
JPhys Energy |
Abbreviated Journal |
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Volume |
2 |
Issue |
3 |
Pages |
032006 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Two-dimensional materials have been attracting increasing interests because of their outstanding properties for Lithium-ion battery applications. In particular, a material family called MXenes (Mn+1Cn, where n = 1, 2, 3) have been recently attracted immense interest in this respect due to their incomparable fast-charging properties and high capacity promises. In this article, we review the state-of-the-art computational progress on Li-ion battery applications of MXene materials in accordance with our systematical DFT calculations. Structural, mechanical, dynamical, and electrical properties of 20 distinct MXene (M: Sc, Ti, V, Cr, Nb, Mo, Hf, Ta, W, and Zr) have been discussed. The battery performances of these MXene monolayers are further investigated by Li-ion binding energies, open circuit voltage values, and Li migration energy barriers. The experimental and theoretical progress up to date demonstrates particularly the potential of non-terminated or pristine MXene materials in Li ion-storage applications. Stability analyses show most of the pristine MXenes should be achievable, however susceptible to the development progress on the experimental growth procedures. Among pristine MXenes, Ti2C, V2C, Sc2C, and Zr2C compounds excel with their high charge/discharge rate prospect due to their extremely low Li diffusion energy barriers. Considering also their higher predicted gravimetric capacities, Sc, Ti, V, and Zr containing MXenes are more promising for their utilization in energy storage applications. |
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Wos |
000569868600001 |
Publication Date |
2020-07-16 |
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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 |
2515-7655 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.9 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 6.9; 2020 IF: NA |
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Call Number |
UA @ admin @ c:irua:193748 |
Serial |
7399 |
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Author |
Bafekry, A.; Yagmurcukardes, M.; Shahrokhi, M.; Ghergherehchi, M. |
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Title |
Electro-optical properties of monolayer and bilayer boron-doped C₃N: Tunable electronic structure via strain engineering and electric field |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
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Volume |
168 |
Issue |
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Pages |
220-229 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
In this work, the structural, electronic and optical properties of monolayer and bilayer of boron doped C3N are investigated by means of density functional theory-based first-principles calculations. Our results show that with increasing the B dopant concentration from 3.1% to 12.5% in the hexagonal pattern, an indirect-to-direct band gap (0.8 eV) transition occurs. Furthermore, we study the effect of electric field and strain on the B doped C3N bilayer (B-C3N@2L). It is shown that by increasing E-field strength from 0.1 to 0.6V/angstrom, the band gap displays almost a linear decreasing trend, while for the > 0.6V/angstrom, we find dual narrow band gap with of 50 meV (in parallel E-field) and 0.4 eV (in antiparallel E-field). Our results reveal that in-plane and out-of-plane strains can modulate the band gap and band edge positions of the B-C3N@2L. Overall, we predict that B-C3N@2L is a new platform for the study of novel physical properties in layered two-dimensional materials (2DM) which may provide new opportunities to realize high-speed low-dissipation devices. (C) 2020 Elsevier Ltd. All rights reserved. |
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Wos |
000565900900008 |
Publication Date |
2020-07-13 |
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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 |
0008-6223 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10.9 |
Times cited |
21 |
Open Access |
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Notes |
; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government(MSIT) (NRF-2017R1A2B2011989). M. Yagmurcukardes acknowledges Flemish Science Foundation (FWO-VI) by a postdoctoral fellowship. ; |
Approved |
Most recent IF: 10.9; 2020 IF: 6.337 |
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Call Number |
UA @ admin @ c:irua:171914 |
Serial |
6500 |
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Author |
Bizindavyi, J.; Verhulst, A.S.; Sorée, B.; Groeseneken, G. |
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Title |
Signature of ballistic band-tail tunneling current in tunnel FET |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Ieee Transactions On Electron Devices |
Abbreviated Journal |
Ieee T Electron Dev |
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Volume |
67 |
Issue |
8 |
Pages |
3486-3491 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
To improve the interpretation of the tunnel field-effect transistor (TFET) measurements, we theoretically identify the signatures of the ballistic band-tail (BT) tunneling (BTT) current in the transfer and output characteristics of the TFETs. In particular, we demonstrate that the temperature dependence of a BTT-dominated subthreshold swing (SS) is in agreement with the reported experimental results. We explain how the temperature dependence of the output characteristics can be used to distinguish between a current dominated by BTT and a current dominated by trap-assisted tunneling. Finally, we propose an expression that relates the energetic extension of the quasi-extended BT states in the bandgap to the onset voltage for tunneling. |
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Wos |
000552976100072 |
Publication Date |
2020-07-03 |
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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 |
0018-9383 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.1 |
Times cited |
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Open Access |
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Notes |
; This work was supported by imec's Industrial Affiliation Program. ; |
Approved |
Most recent IF: 3.1; 2020 IF: 2.605 |
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Call Number |
UA @ admin @ c:irua:171189 |
Serial |
6601 |
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Author |
Torsello, D.; Ummarino, G.A.; Bekaert, J.; Gozzelino, L.; Gerbaldo, R.; Tanatar, M.A.; Canfield, P.C.; Prozorov, R.; Ghigo, G. |
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Title |
Tuning the intrinsic anisotropy with disorder in the CaKFE₄As₄ superconductor |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Physical Review Applied |
Abbreviated Journal |
Phys Rev Appl |
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Volume |
13 |
Issue |
6 |
Pages |
064046-64049 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We report on the anisotropy of the London penetration depth of CaKFe4As4, discussing how it relates to its electronic structure and how it modifies under introduction of disorder, both chemically induced (by Ni substitution) and irradiation induced (by 3.5-MeV protons). Indeed, CaKFe4As4 is particularly suitable for the study of fundamental superconducting properties due to its stoichiometric composition, exhibiting clean-limit behavior in the pristine samples and having a fairly high critical temperature, T-c approximate to 35 K. The London penetration depth lambda(L) is measured with a microwave-coplanar-resonator technique that allows us to deconvolve the anisotropic contributions lambda(L,ab) and lambda(L,c) and obtain the anisotropy parameter gamma(lambda) = lambda(L,c)/lambda(L,ab). The gamma(lambda) (T) found for the undoped pristine sample is in good agreement with previous literature and is here compared to ab initio density-functional-theory and Eliashberg calculations. The dependence of gamma(lambda) (T) on both chemical and irradiation-induced disorder is discussed to highlight which method is more suitable to decrease the direction dependence of the electromagnetic properties while maintaining a high critical temperature. Lastly, the relevance of an intrinsic anisotropy such as gamma(lambda) on application-related anisotropic parameters (critical current, pinning) is discussed in light of the recent employment of CaKFe4As4 in the production of wires. |
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Wos |
000540915800003 |
Publication Date |
2020-06-19 |
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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 |
2331-7019 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.6 |
Times cited |
4 |
Open Access |
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Notes |
; This work was partially supported by the Italian Ministry of Education, University and Research (Project PRIN “HIBiSCUS,” Grant No. 201785KWLE). J.B. acknowledges the support of a postdoctoral fellowship of the Research Foundation-Flanders (FWO). The computational resources and services used for the first-principles calculations in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government-department EWI. Work done at Ames Laboratory was supported by the U.S. Department of Energy, Office of Basic Energy Science, Division of Materials Sciences and Engineering. Ames Laboratory is operated for the U.S. Department of Energy by Iowa State University under Contract No. DE-AC02-07CH11358. G.A.U. acknowledges support from the MEPhI Academic Excellence Project (Contract No. 702.a03.21.0005). ; |
Approved |
Most recent IF: 4.6; 2020 IF: 4.808 |
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Call Number |
UA @ admin @ c:irua:170178 |
Serial |
6641 |
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Author |
Menezes, R.M.; de Souza Silva, C.C.; Milošević, M.V. |
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Title |
Spin textures in chiral magnetic monolayers with suppressed nearest-neighbor exchange |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
101 |
Issue |
21 |
Pages |
214429-9 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
High tunability of two-dimensional magnetic materials (by strain, gating, heterostructuring, or otherwise) provides unique conditions for studying versatile magnetic properties and controlling emergent magnetic phases. Expanding the scope of achievable magnetic phenomena in such materials is important for both fundamental and technological advances. Here we perform atomistic spin-dynamics simulations to explore the (chiral) magnetic phases of atomic monolayers in the limit of suppressed first-neighbors exchange interaction. We report the rich phase diagram of exotic magnetic configurations, obtained for both square and honeycomb lattice symmetries, comprising coexistence of ferromagnetic and antiferromagnetic spin cycloids, as well as multiple types of magnetic skyrmions. We perform a minimum-energy path analysis for the skyrmion collapse to evaluate the stability of such topological objects and reveal that magnetic monolayers could be good candidates to host the antiferromagnetic skyrmions that are experimentally evasive to date. |
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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 |
000540910100002 |
Publication Date |
2020-06-18 |
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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 |
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| |
Impact Factor |
3.7 |
Times cited |
1 |
Open Access |
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| |
Notes |
; This work was supported by the Research Foundation-Flanders (FWO-Vlaanderen) and Brazilian Agencies FACEPE (under Grant No. APQ-0198-1.05/14), CAPES, and CNPq. ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
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| |
Call Number |
UA @ admin @ c:irua:170176 |
Serial |
6610 |
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| Permanent link to this record |
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Author |
Obeid, M.M.; Stampfl, C.; Bafekry, A.; Guan, Z.; Jappor, H.R.; Nguyen, C., V; Naseri, M.; Hoat, D.M.; Hieu, N.N.; Krauklis, A.E.; Tuan V Vu; Gogova, D. |
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Title |
First-principles investigation of nonmetal doped single-layer BiOBr as a potential photocatalyst with a low recombination rate |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Physical Chemistry Chemical Physics |
Abbreviated Journal |
Phys Chem Chem Phys |
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| |
Volume |
22 |
Issue |
27 |
Pages |
15354-15364 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Nonmetal doping is an effective approach to modify the electronic band structure and enhance the photocatalytic performance of bismuth oxyhalides. Using density functional theory, we systematically examine the fundamental properties of single-layer BiOBr doped with boron (B) and phosphorus (P) atoms. The stability of the doped models is investigated based on the formation energies, where the substitutional doping is found to be energetically more stable under O-rich conditions than under Bi-rich ones. The results showed that substitutional doping of P atoms reduced the bandgap of pristine BiOBr to a greater extent than that of boron substitution. The calculation of the effective masses reveals that B doping can render the electrons and holes of pristine BiOBr lighter and heavier, respectively, resulting in a slower recombination rate of photoexcited electron-hole pairs. Based on the results of HOMO-LUMO calculations, the introduction of B atoms tends to increase the number of photocatalytically active sites. The top of the valence band and the conduction band bottom of the B doped BiOBr monolayer match well with the water redox potentials in an acidic environment. The absorption spectra propose that B(P) doping causes a red-shift. Overall, the results predict that nonmetal-doped BiOBr monolayers have a reduced bandgap, a slow recombination rate, more catalytically active sites, enhanced optical absorption edges, and reduced work functions, which will contribute to superior photocatalytic performance. |
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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 |
000549894000018 |
Publication Date |
2020-06-16 |
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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 |
1463-9076; 1463-9084 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.3 |
Times cited |
18 |
Open Access |
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| |
Notes |
; This work was partially supported by the financial support from the Natural Science Foundation of China (Grant No. 11904203) and the Fundamental Research Funds of Shandong University (Grant No. 2019GN065). ; |
Approved |
Most recent IF: 3.3; 2020 IF: 4.123 |
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| |
Call Number |
UA @ admin @ c:irua:171235 |
Serial |
6522 |
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| Permanent link to this record |
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Author |
Zhao, X.N.; Xu, W.; Xiao, Y.M.; Van Duppen, B. |
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Title |
Spin polarization in monolayer MoS₂ in the presence of proximity-induced interactions |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
International Journal Of Modern Physics C |
Abbreviated Journal |
Int J Mod Phys C |
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| |
Volume |
31 |
Issue |
10 |
Pages |
2050143 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
When monolayer (ML) MoS2 is placed on a substrate, the proximity-induced interactions such as the Rashba spin-orbit coupling (RSOC) and exchange interaction (EI) can be introduced. Thus, the electronic system can behave like a spintronic device. In this study, we present a theoretical study on how the presence of the RSCO and EI can lead to the band splitting, the lifting of the valley degeneracy and to the spin polarization in n- and p-type ML MoS2. We find that the maxima of the in-plane spin orientation in the conduction and valence bands in ML MoS2 depend on the Rashba parameter and the effective Zeeman field factor. At a fixed Rashba parameter, the minima of the split conduction band and the maxima of the split valence band along with the spin polarization in ML MoS2 can be tuned effectively by varying the effective Zeeman field factor. On the basis that the EI can be induced by placing the ML MoS2 on a ferromagnetic substrate or by magnetic doping in ML MoS2, we predict that the interesting spintronic effects can be observed in n- and p-type ML MoS2. This work can be helpful to gain an in-depth understanding of the basic physical properties of ML MoS2 for application in advanced electronic and optoelectronic devices. |
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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 |
000583803200009 |
Publication Date |
2020-06-09 |
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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 |
0129-1831 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
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| |
Impact Factor |
1.9 |
Times cited |
|
Open Access |
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| |
Notes |
; This work was supported by the Ministry of Science and Technology of China (Grant No. 2011YQ130018), Department of Science and Technology of Yunnan Province and by the Chinese Academy of Sciences. ; |
Approved |
Most recent IF: 1.9; 2020 IF: 1.171 |
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Call Number |
UA @ admin @ c:irua:173635 |
Serial |
6609 |
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| Permanent link to this record |
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Author |
Zhao, X.N.; Xu, W.; Xiao, Y.M.; Liu, J.; Van Duppen, B.; Peeters, F.M. |
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Title |
Terahertz optical Hall effect in monolayer MoS₂ in the presence of proximity-induced interactions |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
101 |
Issue |
24 |
Pages |
245412-12 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The effect of proximity-induced interactions such as Rashba spin-orbit coupling (SOC) and exchange interaction on the electronic and optical properties of n-type monolayer (ML) MoS2 is investigated. We predict and demonstrate that the Rashba SOC can induce an in-plane spin splitting with terahertz (THz) energy, while the exchange interaction lifts the energy degeneracy in different valleys. Thus, spin polarization can be achieved in an n-type ML MoS2 and valley Hall or optical Hall effect can be observed using linearly polarized THz radiation. In such a case, the transverse optical conductivity sigma(xy) (omega) results from spin-flip transition within spin-split conduction bands and from the fact that contributions from electrons with different spin orientations in different valleys can no longer be canceled out. Interestingly, we find that for fixed effective Zeeman field (or exchange interaction) the lowest spin-split conduction band in ML MoS2 can be tuned from one in the K valley to another one in the K' valley by varying the Rashba parameter lambda(R). Therefore, by changing lambda(R) we can turn the sign of the spin polarization and Im sigma(xy) (omega) from positive to negative. Moreover, we find that the dominant contribution of the selection rules to sigma(xx)(omega) is from electrons in the K valley and to sigma(xy) (omega) is from electrons in the K' valley. These important and interesting theoretical findings can be helpful to experimental observation of the optical Hall effect in valleytronic systems using linearly polarized THz radiation fields. |
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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 |
000538715500011 |
Publication Date |
2020-06-09 |
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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 |
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| |
Impact Factor |
3.7 |
Times cited |
5 |
Open Access |
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Notes |
; This work was supported by the National Natural Science Foundation of China (Grants No. U1930116, No. U1832153, and No. 11574319) and the Center of Science and Technology of Hefei Academy of Science (Grant No. 2016FXZY002). ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
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Call Number |
UA @ admin @ c:irua:170206 |
Serial |
6622 |
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| Permanent link to this record |
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Author |
Conti, S.; Van der Donck, M.; Perali, A.; Peeters, F.M.; Neilson, D. |
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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 |
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| |
Volume |
101 |
Issue |
22 |
Pages |
220504-220506 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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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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 |
000538941900002 |
Publication Date |
2020-06-09 |
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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 |
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Impact Factor |
3.7 |
Times cited |
11 |
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 |
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Call Number |
UA @ admin @ c:irua:170201 |
Serial |
6489 |
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| Permanent link to this record |
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Author |
Wozniak, T.; Faria, P.E., Jr.; Seifert, G.; Chaves, A.; Kunstmann, J. |
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Title |
Exciton g factors of van der Waals heterostructures from first-principles calculations |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
101 |
Issue |
23 |
Pages |
235408-235411 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
External fields are a powerful tool to probe optical excitations in a material. The linear energy shift of an excitation in a magnetic field is quantified by its effective g factor. Here we show how exciton g factors and their sign can be determined by converged first-principles calculations. We apply the method to monolayer excitons in semiconducting transition metal dichalcogenides and to interlayer excitons in MoSe2/WSe2 heterobilayers and obtain good agreement with recent experimental data. The precision of our method allows us to assign measured g factors of optical peaks to specific transitions in the band structure and also to specific regions of the samples. This revealed the nature of various, previously measured interlayer exciton peaks. We further show that, due to specific optical selection rules, g factors in van der Waals heterostructures are strongly spin and stacking-dependent. The calculation of orbital angular momenta requires the summation over hundreds of bands, indicating that for the considered two-dimensional materials the basis set size is a critical numerical issue. The presented approach can potentially be applied to a wide variety of semiconductors. |
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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 |
000537315100009 |
Publication Date |
2020-06-03 |
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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 |
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Impact Factor |
3.7 |
Times cited |
|
Open Access |
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Notes |
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Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
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Call Number |
UA @ admin @ c:irua:170219 |
Serial |
7944 |
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| Permanent link to this record |
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Author |
McNaughton, B.; Milošević, M.V.; Perali, A.; Pilati, S. |
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Title |
Boosting Monte Carlo simulations of spin glasses using autoregressive neural networks |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Physical Review E |
Abbreviated Journal |
Phys Rev E |
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Volume |
101 |
Issue |
5 |
Pages |
053312 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The autoregressive neural networks are emerging as a powerful computational tool to solve relevant problems in classical and quantum mechanics. One of their appealing functionalities is that, after they have learned a probability distribution from a dataset, they allow exact and efficient sampling of typical system configurations. Here we employ a neural autoregressive distribution estimator (NADE) to boost Markov chain Monte Carlo (MCMC) simulations of a paradigmatic classical model of spin-glass theory, namely, the two-dimensional Edwards-Anderson Hamiltonian. We show that a NADE can be trained to accurately mimic the Boltzmann distribution using unsupervised learning from system configurations generated using standard MCMC algorithms. The trained NADE is then employed as smart proposal distribution for the Metropolis-Hastings algorithm. This allows us to perform efficient MCMC simulations, which provide unbiased results even if the expectation value corresponding to the probability distribution learned by the NADE is not exact. Notably, we implement a sequential tempering procedure, whereby a NADE trained at a higher temperature is iteratively employed as proposal distribution in a MCMC simulation run at a slightly lower temperature. This allows one to efficiently simulate the spin-glass model even in the low-temperature regime, avoiding the divergent correlation times that plague MCMC simulations driven by local-update algorithms. Furthermore, we show that the NADE-driven simulations quickly sample ground-state configurations, paving the way to their future utilization to tackle binary optimization problems. |
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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 |
000535862000014 |
Publication Date |
2020-05-28 |
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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 |
1539-3755; 1550-2376 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.366 |
Times cited |
15 |
Open Access |
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Notes |
; The authors thank I. Murray, G. Carleo, and F. RicciTersenghi for useful discussions. Financial support from the FAR2018 project titled “Supervised machine learning for quantum matter and computational docking” of the University of Camerino and from the Italian MIUR under Project No. PRIN2017 CEnTraL 20172H2SC4 is gratefully acknowledged. S.P. also acknowledges the CINECA award under the ISCRA initiative, for the availability of high performance computing resources and support. M.V.M. gratefully acknowledges the Visiting Professorship program at the University of Camerino that facilitated the collaboration in this work. ; |
Approved |
Most recent IF: NA |
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Call Number |
UA @ admin @ c:irua:170244 |
Serial |
6463 |
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| Permanent link to this record |
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Author |
Bafekry, A.; Obeid, M.; Nguyen, C.; Bagheri Tagani, M.; Ghergherehchi, M. |
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Title |
Graphene hetero-multilayer on layered platinum mineral Jacutingaite (Pt₂HgSe₃): Van der Waals heterostructures with novel optoelectronic and thermoelectric performances |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Journal Of Materials Chemistry A |
Abbreviated Journal |
J Mater Chem A |
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Volume |
8 |
Issue |
26 |
Pages |
13248-13260 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Motivated by the recent successful synthesis of the layered platinum mineral jacutingaite (Pt2HgSe3), we have studied the optoelectronic, mechanical, and thermoelectric properties of graphene hetero-multilayer on Pt(2)HgSe(3)monolayer (PHS) heterostructures (LG/PHS) by using first-principles calculations. PHS is a topological insulator with a band gap of about 160 meV with fully relativistic calculations; when graphene layers are stacked on PHS, a narrow band gap of similar to 10-15 meV opens. In the presence of gate-voltage and out-of plane strain,i.e.pressure, the electronic properties are modified; the Dirac-cone of graphene can be shifted upwards (downward) to a lower (higher) binding energy. The absorption spectrum shows two peaks, which are located around 216 nm (5.74 eV) and protracted to 490 nm (2.53 eV), indicating that PHS could absorb more visible light. Increasing the number of graphene layers on PHS has a positive impact on the UV-vis light absorption and gives a clear red-shift with enhanced absorption intensity. To investigate the electronic performance of the heterostructure, the electrical conductance and thermopower of a device composed of graphene layers and PHS is examined by a combination of DFT and Green function formalism. The number of graphene layers can significantly tune the thermopower and electrical conductance. This analysis reveals that the heterostructures not only significantly affect the electronic properties, but they can also be used as an efficient way to modulate the optic and thermoelectric properties. |
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Corporate Author |
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Place of Publication |
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Editor |
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Language |
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Wos |
000546391600032 |
Publication Date |
2020-05-28 |
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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 |
2050-7488; 2050-7496 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
11.9 |
Times cited |
20 |
Open Access |
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Notes |
; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea Government (MSIT) (NRF-2017R1A2B2011989) and Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 103.01-2019.05. ; |
Approved |
Most recent IF: 11.9; 2020 IF: 8.867 |
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Call Number |
UA @ admin @ c:irua:169755 |
Serial |
6529 |
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| Permanent link to this record |
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Author |
Yan, X.F.; Chen, Q.; Li, L.L.; Guo, H.Z.; Peng, J.Z.; Peeters, F.M. |
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Title |
High performance piezotronic spin transistors using molybdenum disulfide nanoribbon |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Nano Energy |
Abbreviated Journal |
Nano Energy |
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Volume |
75 |
Issue |
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Pages |
104953 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Two-dimensional (2D) materials are promising candidates for atomic-scale piezotronics and piezophototronics. Quantum edge states show fascinating fundamental physics such as nontrivial topological behavior and hold promising practical applications for low-power electronic devices. Here, using the tight-binding approach and quantum transport simulations, we investigate the piezotronic effect on the spin polarization of edge states in a zigzag-terminated monolayer MoS2 nanoribbon. We find that the strain-induced piezoelectric potential induces a phase transition of edge states from metal to semiconductor. However, in the presence of exchange field, edge states become semi-metallic with significant spin splitting and polarization that can be tuned by external strain. We show that quantum transport conductance exhibits a 100% spin polarization over a wide range of strain magnitudes. This effect is used in a propose prototype of piezotronic spin transistor. Our results provide a fundamental understanding of the piezotronic effect on edge states in zigzag monolayer MoS2 nanoribbons and are relevant for designing high-performance piezotronic spin devices. |
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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 |
000560729200011 |
Publication Date |
2020-05-24 |
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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 |
2211-2855 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
17.6 |
Times cited |
17 |
Open Access |
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Notes |
; This work was supported by Hunan Provincial Natural Science Foundation of China (Nos. 2015JJ2040, 2018JJ2078), Scientific Research Fund of Hunan Provincial Education Department (19A106), and the Funeral Service Foundation (FWO-VI). ; |
Approved |
Most recent IF: 17.6; 2020 IF: 12.343 |
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Call Number |
UA @ admin @ c:irua:171123 |
Serial |
6535 |
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| Permanent link to this record |
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Author |
Van Pottelberge, R. |
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Title |
Comment on “Electron states for gapped pseudospin-1 fermions in the field of a charged impurity” |
Type |
Editorial |
| |
Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
101 |
Issue |
19 |
Pages |
197102-197103 |
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Keywords |
Editorial; Condensed Matter Theory (CMT) |
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Abstract |
In a recent paper [Phys. Rev. B 99, 155124 (2019)], the spectrum of a regularized Coulomb charge was studied in gapped pseudospin-1 systems generated by an alpha – T-3 lattice. The electronic spectrum was studied as a function of the impurity strength Z alpha. However, the results and conclusions on the behavior of the flatband states as a function of the impurity strength are incomplete. In this Comment, I argue that because of the dispersionless nature of the flatband, the states spread out under the influence of a charged impurity forming a continuous band of states. I support my arguments with explicit numerical calculations which show the emergence of a continuum of states. |
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Place of Publication |
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Editor |
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Language |
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Wos |
000533793600004 |
Publication Date |
2020-05-20 |
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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 |
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| |
Impact Factor |
3.7 |
Times cited |
|
Open Access |
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| |
Notes |
; I would like to acknowledge very insightful discussions with the authors of the commented paper (V. P. Gusynin, E. V. Gorbar, and D. O. Oriekhov). F. M. Peeters is acknowledged for interesting discussions and proofreading. This research was supported by the Flemish Science Foundation through an aspirant research grant for R.V.P. ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
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| |
Call Number |
UA @ admin @ c:irua:169476 |
Serial |
6472 |
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| 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. |
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| |
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) |
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| |
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. |
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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 |
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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 |
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| |
Impact Factor |
4 |
Times cited |
10 |
Open Access |
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| |
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 |
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| |
Call Number |
UA @ admin @ c:irua:170255 |
Serial |
6620 |
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| Permanent link to this record |
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Author |
Griffin, E.; Mogg, L.; Hao, G.-P.; Kalon, G.; Bacaksiz, C.; Lopez-Polin, G.; Zhou, T.Y.; Guarochico, V.; Cai, J.; Neumann, C.; Winter, A.; Mohn, M.; Lee, J.H.; Lin, J.; Kaiser, U.; Grigorieva, I., V; Suenaga, K.; Ozyilmaz, B.; Cheng, H.-M.; Ren, W.; Turchanin, A.; Peeters, F.M.; Geim, A.K.; Lozada-Hidalgo, M. |
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| |
Title |
Proton and Li-Ion permeation through graphene with eight-atom-ring defects |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Acs Nano |
Abbreviated Journal |
Acs Nano |
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| |
Volume |
14 |
Issue |
6 |
Pages |
7280-7286 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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| |
Abstract |
Defect-free graphene is impermeable to gases and liquids but highly permeable to thermal protons. Atomic-scale defects such as vacancies, grain boundaries, and Stone-Wales defects are predicted to enhance graphene's proton permeability and may even allow small ions through, whereas larger species such as gas molecules should remain blocked. These expectations have so far remained untested in experiment. Here, we show that atomically thin carbon films with a high density of atomic-scale defects continue blocking all molecular transport, but their proton permeability becomes similar to 1000 times higher than that of defect-free graphene. Lithium ions can also permeate through such disordered graphene. The enhanced proton and ion permeability is attributed to a high density of eight-carbon-atom rings. The latter pose approximately twice lower energy barriers for incoming protons compared to that of the six-atom rings of graphene and a relatively low barrier of similar to 0.6 eV for Li ions. Our findings suggest that disordered graphene could be of interest as membranes and protective barriers in various Li-ion and hydrogen technologies. |
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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 |
000543744100086 |
Publication Date |
2020-05-19 |
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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 |
1936-0851 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
17.1 |
Times cited |
34 |
Open Access |
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| |
Notes |
; The work was supported by the Lloyd's Register Foundation, EPSRC-EP/N010345/1, the European Research Council, the Graphene Flagship, the Deutsche Forschungsgemeinschaft project TRR 234 “CataLight” (Project B7, Grant No. 364549901), and the research infrastructure Grant No. INST 275/25 7-1 FUGG. E.G. and L.M. acknowledge the EPSRC NowNANO programme for funding. ; |
Approved |
Most recent IF: 17.1; 2020 IF: 13.942 |
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| |
Call Number |
UA @ admin @ c:irua:170708 |
Serial |
6586 |
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| Permanent link to this record |
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Author |
Nakhaee, M.; Ketabi, S.A.; Peeters, F.M. |
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Title |
Tight-binding studio : a technical software package to find the parameters of tight-binding Hamiltonian |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Computer Physics Communications |
Abbreviated Journal |
Comput Phys Commun |
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| |
Volume |
254 |
Issue |
|
Pages |
107379-10 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We present the Tight-Binding Studio (TB Studio) software package that calculates the different parameters of a tight-binding Hamiltonian from a set of Bloch energy bands obtained from first principle theories such as density functional theory, Hartree-Fock calculations or semi-empirical band-structure theory. This will be helpful for scientists who are interested in studying electronic and optical properties of structures using Green's function theory within the tight-binding approximation. TB Studio is a cross-platform application written in C++ with a graphical user interface design that is user-friendly and easy to work with. This software is powered by Linear Algebra Package C interface library for solving the eigenvalue problems and the standard high performance OpenGL graphic library for real time plotting. TB Studio and its examples together with the tutorials are available for download from tight-binding.com. Program summary Program Title: Tight-Binding Studio Program Files doi:http://dx.doi.org/10.17632/j6x5mwzm2d.1 Licensing provisions: LGPL Programming language: C++ External routines: BLAS, LAPACK, LAPACKE, wxWidgets, OpenGL, MathGL Nature of problem: Obtaining Tight-Binding Hamiltonian from a set of Bloch energy bands obtained from first-principles calculations. Solution method: Starting from the simplified LCAO method, a tight-binding model in the two-center approximation is constructed. The Slater and Koster (SK) approach is used to calculate the parameters of the TB Hamiltonian. By using non-linear fitting approaches the optimal values of the SK parameters are obtained such that the TB energy eigenvalues are as close as possible to those from first-principles calculations. We obtain the expression for the Hamiltonian and the overlap matrix elements between the different orbitals of the different atoms in an orthogonal or non-orthogonal basis set. (C) 2020 Elsevier B.V. All rights reserved. |
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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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Language |
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Wos |
000541251200030 |
Publication Date |
2020-05-18 |
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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 |
0010-4655 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
6.3 |
Times cited |
14 |
Open Access |
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Notes |
; This work was supported by the Methusalem program of the Flemish government, Belgium and M. Nakhaee was supported by a BOF-fellowship (UAntwerpen), Belgium. ; |
Approved |
Most recent IF: 6.3; 2020 IF: 3.936 |
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| |
Call Number |
UA @ admin @ c:irua:170149 |
Serial |
6630 |
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| Permanent link to this record |
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Author |
Reijniers, J.; Partoens, B.; Steckel, J.; Peremans, H. |
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Title |
HRTF measurement by means of unsupervised head movements with respect to a single fixed speaker |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Ieee Access |
Abbreviated Journal |
Ieee Access |
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| |
Volume |
8 |
Issue |
|
Pages |
92287-92300 |
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Keywords |
A1 Journal article; Mass communications; Engineering Management (ENM); Condensed Matter Theory (CMT); Co-Design of Cyber-Physical Systems (Cosys-Lab) |
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Abstract |
In a standard state-of-the-art measurement the head-related transfer function (HRTF) is obtained in an anechoic room with an elaborate setup involving multiple calibrated loudspeakers. In search for a simplified method that would open up the possibility for an HRTF measurement in a home environment, it has been suggested that this setup could be replaced with one with a single, fixed loudspeaker. In such a setup, the subject samples different directions by moving the head with respect to this loudspeaker, while the head movements are tracked in some way. In this paper, the feasibility of such an approach is studied. To this end, the HRTF is measured in an unmodified (non-anechoic) room by means of a single external speaker and a high resolution head tracking system. The differences between the dynamically obtained HRTF and the standard static HRTF are investigated, and are shown to be mostly due to variable torso reflections. |
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Corporate Author |
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Place of Publication |
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Editor |
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Language |
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Wos |
000539041600001 |
Publication Date |
2020-05-15 |
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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 |
2169-3536 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.9 |
Times cited |
4 |
Open Access |
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Notes |
; This work was supported in part by the Research Foundation Flanders (FWO) under Grant G023619N, and in part by the Agency for Innovation and Entrepreneurship (VLAIO). ; |
Approved |
Most recent IF: 3.9; 2020 IF: 3.244 |
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Call Number |
UA @ admin @ c:irua:170318 |
Serial |
6539 |
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| Permanent link to this record |
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Author |
Kong, X.; Li, L.; Liang, L.; Peeters, F.M.; Liu, X.-J. |
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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 |
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| |
Volume |
116 |
Issue |
19 |
Pages |
192404-192405 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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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. |
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Publisher |
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Place of Publication |
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Wos |
000533500900001 |
Publication Date |
2020-05-11 |
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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 |
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Impact Factor |
4 |
Times cited |
13 |
Open Access |
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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 |
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Call Number |
UA @ admin @ c:irua:169496 |
Serial |
6623 |
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Author |
Gjerding, M.N.; Cavalcante, L.S.R.; Chaves, A.; Thygesen, K.S. |
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Title |
Efficient Ab initio modeling of dielectric screening in 2D van der Waals materials : including phonons, substrates, and doping |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Journal Of Physical Chemistry C |
Abbreviated Journal |
J Phys Chem C |
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Volume |
124 |
Issue |
21 |
Pages |
11609-11616 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
The quantum electrostatic heterostructure (QEH) model allows for efficient computation of the dielectric screening properties of layered van der Waals (vdW)-bonded heterostructures in terms of the dielectric functions of the individual two-dimensional (2D) layers. Here, we extend the QEH model by including (1) contributions to the dielectric function from infrared active phonons in the 2D layers, (2) screening from homogeneous bulk substrates, and (3) intraband screening from free carriers in doped 2D semiconductor layers. We demonstrate the potential of the extended QEH model by calculating the dispersion of coupled phonons in multilayer stacks of hexagonal boron-nitride (hBN), the strong hybridization of plasmons and optical phonons in graphene/hBN heterostructures, the effect of substrate screening on the exciton series of monolayer MoS2, and the properties of hyperbolic plasmons in a doped phosphorene sheet. The new QEH code is distributed as a Python package with a simple command line interface and a comprehensive library of dielectric building blocks for the most common 2D materials, providing an efficient open platform for dielectric modeling of realistic vdW heterostructures. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000614615900022 |
Publication Date |
2020-05-04 |
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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 |
1932-7447; 1932-7455 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.7 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.7; 2020 IF: 4.536 |
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Call Number |
UA @ admin @ c:irua:176187 |
Serial |
7852 |
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Author |
Baskurt, M.; Yagmurcukardes, M.; Peeters, F.M.; Sahin, H. |
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Title |
Stable single-layers of calcium halides (CaX₂, X = F, Cl, Br, I) |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Journal Of Chemical Physics |
Abbreviated Journal |
J Chem Phys |
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Volume |
152 |
Issue |
16 |
Pages |
164116-164118 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
By means of density functional theory based first-principles calculations, the structural, vibrational, and electronic properties of 1H- and 1T-phases of single-layer CaX2 (X = F, Cl, Br, or I) structures are investigated. Our results reveal that both the 1H- and 1T-phases are dynamically stable in terms of their phonon band dispersions with the latter being the energetically favorable phase for all single-layers. In both phases of single-layer CaX2 structures, significant phonon softening occurs as the atomic radius increases. In addition, each structural phase exhibits distinctive Raman active modes that enable one to characterize either the phase or the structure via Raman spectroscopy. The electronic band dispersions of single-layer CaX2 structures reveal that all structures are indirect bandgap insulators with a decrease in bandgaps from fluorite to iodide crystals. Furthermore, the calculated linear elastic constants, in-plane stiffness, and Poisson ratio indicate the ultra-soft nature of CaX2 single-layers, which is quite important for their nanoelastic applications. Overall, our study reveals that with their dynamically stable 1T- and 1H-phases, single-layers of CaX2 crystals can be alternative ultra-thin insulators. |
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Place of Publication |
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Language |
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Wos |
000531819100001 |
Publication Date |
2020-04-29 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0021-9606 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
4.4 |
Times cited |
10 |
Open Access |
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Notes |
; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. acknowledges financial support from the TUBITAK under Project No. 117F095. H.S. acknowledges support from the Turkish Academy of Sciences under the GEBIP program. M.Y. was supported by a postdoctoral fellowship from the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 4.4; 2020 IF: 2.965 |
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Call Number |
UA @ admin @ c:irua:169543 |
Serial |
6615 |
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Author |
Bafekry, A.; Akgenc, B.; Ghergherehchi, M.; Peeters, F.M. |
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Title |
Strain and electric field tuning of semi-metallic character WCrCO₂ MXenes with dual narrow band gap |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Journal Of Physics-Condensed Matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
32 |
Issue |
35 |
Pages |
355504-355508 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Motivated by the recent successful synthesis of double-M carbides, we investigate structural and electronic properties of WCrC and WCrCO2 monolayers and the effects of biaxial and out-of-plane strain and electric field using density functional theory. WCrC and WCrCO2 monolayers are found to be dynamically stable. WCrC is metallic and WCrCO2 display semi-metallic character with narrow band gap, which can be controlled by strain engineering and electric field. WCrCO2 monolayer exhibits a dual band gap which is preserved in the presence of an electric field. The band gap of WCrCO2 monolayer increases under uniaxial strain while it becomes metallic under tensile strain, resulting in an exotic 2D double semi-metallic behavior. Our results demonstrate that WCrCO2 is a new platform for the study of novel physical properties in two-dimensional Dirac materials and which may provide new opportunities to realize high-speed low-dissipation devices. |
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Place of Publication |
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Wos |
000539375800001 |
Publication Date |
2020-04-29 |
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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 |
0953-8984 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.7 |
Times cited |
37 |
Open Access |
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Notes |
; This work was supported by the National Research Foundation of Korea(NRF) Grant funded by the Korea government(MSIT)(NRF-2017R1A2B2011989). In addition, this work was supported by the Flemish Science Foundation (FW0-Vl). ; |
Approved |
Most recent IF: 2.7; 2020 IF: 2.649 |
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Call Number |
UA @ admin @ c:irua:169756 |
Serial |
6616 |
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| Permanent link to this record |
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Author |
Yagmurcukardes, M.; Peeters, F.M. |
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Title |
Stable single layer of Janus MoSO: strong out-of-plane piezoelectricity |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
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Volume |
101 |
Issue |
15 |
Pages |
155205-155208 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Using density functional theory based first-principles calculations, we predict the dynamically stable 1H phase of a Janus single layer composed of S-Mo-O atomic layers. It is an indirect band gap semiconductor exhibiting strong polarization arising from the charge difference on the two surfaces. In contrast to 1H phases of MoS2 and MoO2, Janus MoSO is found to possess four Raman active phonon modes and a large out-of-plane piezoelectric coefficient which is absent in fully symmetric single layers of MoS2 and MoO2. We investigated the electronic and phononic properties under applied biaxial strain and found an electronic phase transition with tensile strain while the conduction band edge displays a shift when under compressive strain. Furthermore, single-layer MoSO exhibits phononic stability up to 5% of compressive and 11% of tensile strain with significant phonon shifts. The phonon instability is shown to arise from the soft in-plane and out-of-plane acoustic modes at finite wave vector. The large strain tolerance of Janus MoSO is important for nanoelastic applications. In view of the dynamical stability even under moderate strain, we expect that Janus MoSO can be fabricated in the common 1H phase with a strong out-of-plane piezoelectric coefficient. |
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Place of Publication |
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Language |
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Wos |
000528507900003 |
Publication Date |
2020-04-24 |
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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 |
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| |
Impact Factor |
3.7 |
Times cited |
49 |
Open Access |
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Notes |
; Computational resources were provided by the Flemish Supercomputer Center (VSC). M.Y. is supported by the Flemish Science Foundation (FWO-Vl) through a postdoctoral fellowship. ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
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Call Number |
UA @ admin @ c:irua:169566 |
Serial |
6614 |
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Author |
Bafekry, A.; Stampfl, C.; Peeters, F.M. |
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Title |
The electronic, optical, and thermoelectric properties of monolayer PbTe and the tunability of the electronic structure by external fields and defects |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Physica Status Solidi B-Basic Solid State Physics |
Abbreviated Journal |
Phys Status Solidi B |
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Volume |
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Issue |
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Pages |
2000182-12 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
First‐principles calculations, within the framework of density functional theory, are used to investigate the structural, electronic, optical, and thermoelectric properties of monolayer PbTe. The effect of layer thickness, electric field, strain, and vacancy defects on the electronic and magnetic properties is systematically studied. The results show that the bandgap decreases as the layer thickness increases from monolayer to bulk. With application of an electric field on bilayer PbTe, the bandgap decreases from 70 meV (0.2 V Å⁻¹) to 50 meV (1 V Å⁻¹) when including spin–orbit coupling (SOC). Application of uniaxial strain induces a direct‐to‐indirect bandgap transition for strain greater than +6%. In addition, the bandgap decreases under compressive biaxial strain (with SOC). The effect of vacancy defects on the electronic properties of PbTe is also investigated. Such vacancy defects turn PbTe into a ferromagnetic metal (single vacancy Pb) with a magnetic moment of 1.3 μB, and into an indirect semiconductor with bandgap of 1.2 eV (single Te vacancy) and 1.5 eV (double Pb + Te vacancy). In addition, with change of the Te vacancy concentration, a bandgap of 0.38 eV (5.55%), 0.43 eV (8.33%), and 0.46 eV (11.11%) is predicted. |
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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 |
000527679200001 |
Publication Date |
2020-04-23 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-1972 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.6 |
Times cited |
37 |
Open Access |
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Notes |
; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). In addition, this work was supported by the FLAG-ERA project 2DTRANS TMD and the Flemish Science Foundation (FWO-Vl). The authors are thankful for comments by Mohan Verma from the Computational Nanoionics Research Lab, Department of Applied Physics, Bhilai, India and to Francesco Buonocore from ENEA, Casaccia Research Centre, Rome, Italy. ; |
Approved |
Most recent IF: 1.6; 2020 IF: 1.674 |
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Call Number |
UA @ admin @ c:irua:168730 |
Serial |
6502 |
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Author |
Bekaert, J.; Khestanova, E.; Hopkinson, D.G.; Birkbeck, J.; Clark, N.; Zhu, M.; Bandurin, D.A.; Gorbachev, R.; Fairclough, S.; Zou, Y.; Hamer, M.; Terry, D.J.; Peters, J.J.P.; Sanchez, A.M.; Partoens, B.; Haigh, S.J.; Milošević, M.V.; Grigorieva, I., V |
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Title |
Enhanced superconductivity in few-layer TaS₂ due to healing by oxygenation |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Nano Letters |
Abbreviated Journal |
Nano Lett |
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Volume |
20 |
Issue |
5 |
Pages |
3808-3818 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
When approaching the atomically thin limit, defects and disorder play an increasingly important role in the properties of two-dimensional (2D) materials. While defects are generally thought to negatively affect superconductivity in 2D materials, here we demonstrate the contrary in the case of oxygenation of ultrathin tantalum disulfide (TaS2). Our first-principles calculations show that incorporation of oxygen into the TaS2 crystal lattice is energetically favorable and effectively heals sulfur vacancies typically present in these crystals, thus restoring the electronic band structure and the carrier density to the intrinsic characteristics of TaS2. Strikingly, this leads to a strong enhancement of the electron-phonon coupling, by up to 80% in the highly oxygenated limit. Using transport measurements on fresh and aged (oxygenated) few-layer TaS2, we found a marked increase of the superconducting critical temperature (T-c) upon aging, in agreement with our theory, while concurrent electron microscopy and electron-energy loss spectroscopy confirmed the presence of sulfur vacancies in freshly prepared TaS2 and incorporation of oxygen into the crystal lattice with time. Our work thus reveals the mechanism by which certain atomic-scale defects can be beneficial to superconductivity and opens a new route to engineer T-c in ultrathin materials. |
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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 |
000535255300114 |
Publication Date |
2020-04-20 |
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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 |
1530-6984 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
10.8 |
Times cited |
16 |
Open Access |
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Notes |
; This work was supported by Research Foundation-Flanders (FWO). J.Be. acknowledges support of a postdoctoral fellowship of the FWO. The computational resources and services used for the first-principles calculations in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government-department EWI. S.J.H., D.H., and S.F. would like to thank the Engineering and Physical Sciences Research Council (EPSRC) U.K (grants EP/R031711/1, EP/P009050/1 and the Graphene NOWNANO CDT) and the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement ERC-2016-STG-EvoluTEM-715502, the Hetero2D Synergy grant and EC-FET Graphene Flagship) for funding. We thank Diamond Light Source for access and support in use of the electron Physical Science Imaging Centre (Instrument E02 and proposal numbers EM19315 and MG21597) that contributed to the results presented here. ; |
Approved |
Most recent IF: 10.8; 2020 IF: 12.712 |
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Call Number |
UA @ admin @ c:irua:170264 |
Serial |
6507 |
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| Permanent link to this record |
