| Records |
| Author |
Chen, X.; Bouhon, A.; Li, L.; Peeters, F.M.; Sanyal, B. |
| Title |
PAI-graphene : a new topological semimetallic two-dimensional carbon allotrope with highly tunable anisotropic Dirac cones |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| Volume |
170 |
Issue |
|
Pages |
477-486 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Using evolutionary algorithm for crystal structure prediction, we present a new stable two-dimensional (2D) carbon allotrope composed of polymerized as-indacenes (PAI) in a zigzag pattern, namely PAI-graphene whose energy is lower than most of the reported 2D allotropes of graphene. Crucially, the crystal structure realizes a nonsymmorphic layer group that enforces a nontrivial global topology of the band structure with two Dirac cones lying perfectly at the Fermi level. The absence of electron/hole pockets makes PAI-graphene a pristine crystalline topological semimetal having anisotropic Fermi velocities with a high value of 7.0 x 10(5) m/s. We show that while the semimetallic property of the allotrope is robust against the application of strain, the positions of the Dirac cone and the Fermi velocities can be modified significantly with strain. Moreover, by combining strain along both the x- and y-directions, two band inversions take place at G leading to the annihilation of the Dirac nodes demonstrating the possibility of strain-controlled conversion of a topological semimetal into a semiconductor. Finally we formulate the bulk-boundary correspondence of the topological nodal phase in the form of a generalized Zak-phase argument finding a perfect agreement with the topological edge states computed for different edge-terminations. (C) 2020 The Author(s). Published by Elsevier Ltd. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000579779800047 |
Publication Date |
2020-08-21 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0008-6223 |
ISBN |
|
Additional Links  |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
10.9 |
Times cited |
27 |
Open Access |
|
| Notes |
; We thank S. Nahas, for helpful discussions. This work is supported by the project grant (2016e05366) and Swedish Research Links program grant (2017e05447) from the Swedish Research Council, the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl), the FLAG-ERA project TRANS 2D TMD. Linyang Li acknowledges financial support from the Natural Science Foundation of Hebei Province (Grant No. A2020202031). X.C. thanks China scholarship council for financial support (No. 201606220031). X.C. and B.S. acknowledge SNIC-UPPMAX, SNIC-HPC2N, and SNIC-NSC centers under the Swedish National Infrastructure for Computing (SNIC) resources for the allocation of time in high-performance supercomputers. Moreover, supercomputing resources from PRACE DECI-15 project DYNAMAT are gratefully acknowledged. ; |
Approved |
Most recent IF: 10.9; 2020 IF: 6.337 |
| Call Number |
UA @ admin @ c:irua:173513 |
Serial |
6577 |
| Permanent link to this record |
| |
|
| |
| Author |
Plumadore, R.; Baskurt, M.; Boddison-Chouinard, J.; Lopinski, G.; Modarresi, M.; Potasz, P.; Hawrylak, P.; Sahin, H.; Peeters, F.M.; Luican-Mayer, A. |
| Title |
Prevalence of oxygen defects in an in-plane anisotropic transition metal dichalcogenide |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
102 |
Issue |
20 |
Pages |
205408 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Atomic scale defects in semiconductors enable their technological applications and realization of different quantum states. Using scanning tunneling microscopy and spectroscopy complemented by ab initio calculations we determine the nature of defects in the anisotropic van der Waals layered semiconductor ReS2. We demonstrate the in-plane anisotropy of the lattice by directly visualizing chains of rhenium atoms forming diamond-shaped clusters. Using scanning tunneling spectroscopy we measure the semiconducting gap in the density of states. We reveal the presence of lattice defects and by comparison of their topographic and spectroscopic signatures with ab initio calculations we determine their origin as oxygen atoms absorbed at lattice point defect sites. These results provide an atomic-scale view into the semiconducting transition metal dichalcogenides, paving the way toward understanding and engineering their properties. |
| 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 |
000587595800007 |
Publication Date |
2020-11-09 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.7 |
Times cited |
6 |
Open Access |
|
| Notes |
; The authors acknowledge funding from National Sciences and Engineering Research Council (NSERC) Discovery Grant No. RGPIN-2016-06717. We also acknowledge the support of the Natural Sciences and Engineering Research Council of Canada (NSERC) through QC2DM Strategic Project No. STPGP 521420. P.H. thanks uOttawa Research Chair in Quantum Theory of Materials for support. P.P. acknowledges partial financial support from National Science Center (NCN), Poland, Grant Maestro No. 2014/14/A/ST3/00654, and calculations were performed in theWroclaw Center for Networking and Supercomputing. H.S. acknowledges financial support from TUBITAK under Project No. 117F095 and from Turkish Academy of Sciences under the GEBIP program. Our computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid eInfrastructure). ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:173525 |
Serial |
6584 |
| Permanent link to this record |
| |
|
| |
| Author |
Li, Q.N.; Xu, W.; Xiao, Y.M.; Ding, L.; Van Duppen, B.; Peeters, F.M. |
| Title |
Optical absorption window in Na₃Bi based three-dimensional Dirac electronic system |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Journal Of Applied Physics |
Abbreviated Journal |
J Appl Phys |
| Volume |
128 |
Issue |
15 |
Pages |
155707 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We present a detailed theoretical study of the optoelectronic properties of a Na3Bi based three-dimensional Dirac electronic system (3DDES). The optical conductivity is evaluated using the energy-balance equation derived from a Boltzmann equation, where the electron Hamiltonian is taken from a simplified k . p approach. We find that for short-wavelength irradiation, the optical absorption in Na3Bi is mainly due to inter-band electronic transitions. In contrast to the universal optical conductance observed for graphene, the optical conductivity for Na3Bi based 3DDES depends on the radiation frequency but not on temperature, carrier density, and electronic relaxation time. In the radiation wavelength regime of about 5 mu m, < lambda < 200 mu m, an optical absorption window is found. This is similar to what is observed in graphene. The position and width of the absorption window depend on the direction of the light polarization and sensitively on temperature, carrier density, and electronic relaxation time. Particularly, we demonstrate that the inter-band optical absorption channel can be switched on and off by applying the gate voltage. This implies that similar to graphene, Na3Bi based 3DDES can also be applied in infrared electro-optical modulators. Our theoretical findings are helpful in gaining an in-depth understanding of the basic optoelectronic properties of recently discovered 3DDESs. |
| 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 |
000585807400004 |
Publication Date |
2020-10-21 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
3.2 |
Times cited |
|
Open Access |
|
| Notes |
; This work was supported by the National Natural Science Foundation of China (NNSFC Nos. U1930116, U1832153, 11764045, 11574319, and 11847054) and the Center of Science and Technology of Hefei Academy of Science (No. 2016FXZY002). Applied Basic Research Foundation of Department of Science and Technology of Yunnan Province (No. 2019FD134), the Department of Education of Yunnan Province (No. 2018JS010), the Young Backbone Teachers Training Program of Yunnan University, and the Department of Science and Technology of Yunnan Province are acknowledged. ; |
Approved |
Most recent IF: 3.2; 2020 IF: 2.068 |
| Call Number |
UA @ admin @ c:irua:173591 |
Serial |
6571 |
| Permanent link to this record |
| |
|
| |
| Author |
Nakhaee, M.; Ketabi, S.A.; Peeters, F.M. |
| Title |
Machine learning approach to constructing tight binding models for solids with application to BiTeCl |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Journal Of Applied Physics |
Abbreviated Journal |
J Appl Phys |
| Volume |
128 |
Issue |
21 |
Pages |
215107 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Finding a tight-binding (TB) model for a desired solid is always a challenge that is of great interest when, e.g., studying transport properties. A method is proposed to construct TB models for solids using machine learning (ML) techniques. The approach is based on the LCAO method in combination with Slater-Koster (SK) integrals, which are used to obtain optimal SK parameters. The lattice constant is used to generate training examples to construct a linear ML model. We successfully used this method to find a TB model for BiTeCl, where spin-orbit coupling plays an essential role in its topological behavior. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000597311900001 |
Publication Date |
2020-12-03 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.2 |
Times cited |
2 |
Open Access |
|
| Notes |
; This work was supported by the Methusalem program of the Flemish government and was partially supported by BOF (UAntwerpen Grant Reference No. ADPERS/BAP/RS/ 2019). We would like to thank one of the anonymous referees for assisting us in making the paper more accessible to the reader. ; |
Approved |
Most recent IF: 3.2; 2020 IF: 2.068 |
| Call Number |
UA @ admin @ c:irua:174380 |
Serial |
6691 |
| Permanent link to this record |
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| |
| Author |
Lavor, I.R.; da Costa, D.R.; Chaves, A.; Sena, S.H.R.; Farias, G.A.; Van Duppen, B.; Peeters, F.M. |
| Title |
Effect of zitterbewegung on the propagation of wave packets in ABC-stacked multilayer graphene : an analytical and computational approach |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Journal Of Physics-Condensed Matter |
Abbreviated Journal |
J Phys-Condens Mat |
| Volume |
33 |
Issue |
9 |
Pages |
095503 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The time evolution of a low-energy two-dimensional Gaussian wave packet in ABC-stacked n-layer graphene (ABC-NLG) is investigated. Expectation values of the position (x, y) of center-of-mass and the total probability densities of the wave packet are calculated analytically using the Green's function method. These results are confirmed using an alternative numerical method based on the split-operator technique within the Dirac approach for ABC-NLG, which additionally allows to include external fields and potentials. The main features of the zitterbewegung (trembling motion) of wave packets in graphene are demonstrated and are found to depend not only on the wave packet width and initial pseudospin polarization, but also on the number of layers. Moreover, the analytical and numerical methods proposed here allow to investigate wave packet dynamics in graphene systems with an arbitrary number of layers and arbitrary potential landscapes. |
| 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 |
000599465000001 |
Publication Date |
2020-11-25 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.649 |
Times cited |
3 |
Open Access |
OpenAccess |
| Notes |
; Discussions with D J P de Sousa and J M Pereira Jr are gratefully acknowledged. This work was financially supported by the Brazilian Council for Research (CNPq), under the PQ and PRONEX/FUNCAP programs, and by CAPES. One of us (BVD) is supported by the FWO-Vl. DRC is supported by CNPq Grant Nos. 310019/2018-4 and 437067/2018-1. ; |
Approved |
Most recent IF: 2.649 |
| Call Number |
UA @ admin @ c:irua:174953 |
Serial |
6687 |
| Permanent link to this record |
| |
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| |
| Author |
Jiang, J.; Wang, Y.-L.; Milošević, M.V.; Xiao, Z.-L.; Peeters, F.M.; Chen, Q.-H. |
| Title |
Reversible ratchet effects in a narrow superconducting ring |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
103 |
Issue |
1 |
Pages |
014502 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We study the ratchet effect in a narrow pinning-free superconductive ring based on time-dependent Ginzburg-Landau (TDGL) equations. Voltage responses to external dc and ac currents at various magnetic fields are studied. Due to asymmetric barriers for flux penetration and flux exit in the ring-shaped superconductor, the critical current above which the flux-flow state is reached, as well as the critical current for the transition to the normal state, are different for the two directions of applied current. These effects cooperatively cause ratchet signal reversal at high magnetic fields, which has not been reported to date in a pinning-free system. The ratchet signal found here is larger than those induced by asymmetric pinning potentials. Our results also demonstrate the feasibility of using mesoscopic superconductors to employ a superconducting diode effect in versatile superconducting devices. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
|
| Language |
|
Wos |
000604821500003 |
Publication Date |
2021-01-05 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
2 |
Open Access |
OpenAccess |
| Notes |
; We are grateful to G. Berdiyorov for useful suggestions and comments. Q.-H.C. thanks Beiyi Zhu for helpful discussions during the early stage of this work. This work is supported in part by the National Key Research and Development Program of China, Grants No. 2017YFA0303002 (Q.-H.C. and J.J.), and No. 2018YFA0209002 (Y.-L.W.), and the National Natural Science Foundation of China Grants No. 11834005, No. 11674285, No. 61771235, and No. 61727805. Z.-L.X. acknowledges support by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering and the National Science Foundation under Grant No. DMR-1901843. F.M.P. and M.V.M. acknowledge support by the Research Foundation – Flanders (FWO). ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:174984 |
Serial |
6697 |
| Permanent link to this record |
| |
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| |
| Author |
Pandey, T.; Covaci, L.; Peeters, F.M. |
| Title |
Tuning flexoelectricty and electronic properties of zig-zag graphene nanoribbons by functionalization |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| Volume |
171 |
Issue |
|
Pages |
551-559 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
| Abstract |
The flexoelectric and electronic properties of zig-zag graphene nanoribbons are explored under mechanical bending using state of the art first principles calculations. A linear dependence of the bending induced out of plane polarization on the applied strain gradient is found. The inferior flexoelectric properties of graphene nanoribbons can be improved by more than two orders of magnitude by hydrogen and fluorine functionalization (CH and CF nanoribbons). A large out of plane flexoelectric effect is predicted for CF nanoribbons. The origin of this enhancement lies in the electro-negativity difference between carbon and fluorine atoms, which breaks the out of plane charge symmetry even for a small strain gradient. The flexoelectric effect can be further improved by co-functionalization with hydrogen and fluorine (CHF Janus-type nanoribbon), where a spontaneous out of plane dipole moment is formed even for flat nanoribbons. We also find that bending can control the charge localization of valence band maxima and therefore enables the tuning of the hole effective masses and band gaps. These results present an important advance towards the understanding of flexoelectric and electronic properties of hydrogen and fluorine functionalized graphene nanoribbons, which can have important implications for flexible electronic applications. (C) 2020 Elsevier Ltd. All rights reserved. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000598371500058 |
Publication Date |
2020-09-17 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0008-6223 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.337 |
Times cited |
11 |
Open Access |
OpenAccess |
| Notes |
; 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 Flemish Science Foundation (FWO-VI). T. P. is supported by a postdoctoral research fellowship from BOF-UAntwerpen. ; |
Approved |
Most recent IF: 6.337 |
| Call Number |
UA @ admin @ c:irua:175014 |
Serial |
6700 |
| Permanent link to this record |
| |
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| |
| Author |
Milovanović, S.P.; Andelkovic, M.; Covaci, L.; Peeters, F.M. |
| Title |
Band flattening in buckled monolayer graphene |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
102 |
Issue |
24 |
Pages |
245427 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
| Abstract |
The strain fields of periodically buckled graphene induce a periodic pseudomagnetic field (PMF) that modifies the electronic band structure. From the geometry, amplitude, and period of the periodic pseudomagnetic field, we determine the necessary conditions to access the regime of correlated phases by examining the band flattening. As compared to twisted bilayer graphene the proposed system has the advantages that (1) only a single layer of graphene is needed, (2) one is not limited to hexagonal superlattices, and (3) narrower flat bandwidth and larger separation between flat bands can be induced. We, therefore, propose that periodically strained graphene single layers can become a platform for the exploration of exotic many-body phases. |
| 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 |
000602844600007 |
Publication Date |
2020-12-28 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.7 |
Times cited |
11 |
Open Access |
OpenAccess |
| Notes |
; S.P.M. is supported by the Flemish Science Foundation (FWO). We thank E. Y. Andrei, Y. Jiang, and J. Mao for fruitful discussions. ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:175021 |
Serial |
6684 |
| Permanent link to this record |
| |
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| |
| Author |
Wang, H.; Su, L.; Yagmurcukardes, M.; Chen, J.; Jiang, Y.; Li, Z.; Quan, A.; Peeters, F.M.; Wang, C.; Geim, A.K.; Hu, S. |
| Title |
Blue energy conversion from holey-graphene-like membranes with a high density of subnanometer pores |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Nano Letters |
Abbreviated Journal |
Nano Lett |
| Volume |
20 |
Issue |
12 |
Pages |
8634-8639 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
Blue energy converts the chemical potential difference from salinity gradients into electricity via reverse electrodialysis and provides a renewable source of clean energy. To achieve high energy conversion efficiency and power density, nanoporous membrane materials with both high ionic conductivity and ion selectivity are required. Here, we report ion transport through a network of holey-graphene-like sheets made by bottom-up polymerization. The resulting ultrathin membranes provide controlled pores of <10 angstrom in diameter with an estimated density of about 10(12) cm(-2). The pores' interior contains NH2 groups that become electrically charged with varying pH and allow tunable ion selectivity. Using the holey-graphene-like membranes, we demonstrate power outputs reaching hundreds of watts per square meter. The work shows a viable route toward creating membranes with high-density angstrom-scale pores, which can be used for energy generation, ion separation, and related technologies. |
| 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 |
000599507100032 |
Publication Date |
2020-11-12 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1530-6984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
10.8 |
Times cited |
29 |
Open Access |
|
| Notes |
; The authors acknowledge supported from National Key Research and Development Program of China (2019YFA0705400, 2018YFA0209500), and National Natural Science Foundation of China (21972121, 21671162). M. Y. acknowledges the Flemish Science Foundation (FWO-Vl) postdoctoral fellowship. ; |
Approved |
Most recent IF: 10.8; 2020 IF: 12.712 |
| Call Number |
UA @ admin @ c:irua:175048 |
Serial |
6685 |
| Permanent link to this record |
| |
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| |
| Author |
Ceyhan, E.; Yagmurcukardes, M.; Peeters, F.M.; Sahin, H. |
| Title |
Electronic and magnetic properties of single-layer FeCl₂ with defects |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
103 |
Issue |
1 |
Pages |
014106 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The formation of lattice defects and their effect on the electronic properties of single-layer FeCl2 are investigated by means of first-principles calculations. Among the vacancy defects, namely mono-, di-, and three-Cl vacancies and mono-Fe vacancy, the formation of mono-Cl vacancy is the most preferable. Comparison of two different antisite defects reveals that the formation of the Fe-antisite defect is energetically preferable to the Cl-antisite defect. While a single Cl vacancy leads to a 1 mu(B) decrease in the total magnetic moment of the host lattice, each Fe vacant site reduces the magnetic moment by 4 mu(B). However, adsorption of an excess Cl atom on the surface changes the electronic structure to a ferromagnetic metal or to a ferromagnetic semiconductor depending on the adsorption site without changing the ferromagnetic state of the host lattice. Both Cl-antisite and Fe-antisite defected domains change the magnetic moment of the host lattice by -1 mu(B) and +3 mu(B), respectively. The electronic ground state of defected structures reveals that (i) single-layer FeCl2 exhibits half-metallicity under the formation of vacancy and Cl-antisite defects; (ii) ferromagnetic metallicity is obtained when a single Cl atom is adsorbed on upper-Cl and Fe sites, respectively; and (iii) ferromagnetic semiconducting behavior is found when a Cl atom is adsorbed on a lower-Cl site or a Fe-antisite defect is formed. Simulated scanning electron microscope images show that atomic-scale identification of defect types is possible from their electronic charge density. Further investigation of the periodically Fe-defected structures reveals that the formation of the single-layer FeCl3 phase, which is a dynamically stable antiferromagnetic semiconductor, is possible. Our comprehensive analysis on defects in single-layer FeCl2 will complement forthcoming experimental observations. |
| 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 |
000606969400002 |
Publication Date |
2021-01-13 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
5 |
Open Access |
Not_Open_Access |
| Notes |
; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and by Flemish Supercomputer Center (VSC). H.S. acknowledges financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 117F095. M.Y. was supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship. ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:176039 |
Serial |
6689 |
| Permanent link to this record |
| |
|
| |
| Author |
Jalali, H.; Khoeini, F.; Peeters, F.M.; Neek-Amal, M. |
| Title |
Hydration effects and negative dielectric constant of nano-confined water between cation intercalated MXenes |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
| Volume |
13 |
Issue |
2 |
Pages |
922-929 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
Using electrochemical methods a profound enhancement of the capacitance of electric double layer capacitor electrodes was reported when water molecules are strongly confined into the two-dimensional slits of titanium carbide MXene nanosheets [A. Sugahara et al., Nat. Commun., 2019, 10, 850]. We study the effects of hydration on the dielectric properties of nanoconfined water and supercapacitance properties of the cation intercalated MXene. A model for the electric double layer capacitor is constructed where water molecules are strongly confined in two-dimensional slits of MXene. We report an abnormal dielectric constant and polarization of nano-confined water between MXene layers. We found that by decreasing the ionic radius of the intercalated cations and in a critical hydration shell radius the capacitance of the system increases significantly (similar or equal to 200 F g(-1)) which can be interpreted as a negative permittivity. This study builds a bridge between the fundamental understanding of the dielectric properties of nanoconfined water and the capability of using MXene films for supercapacitor technology, and in doing so provides a solid theoretical support for recent experiments. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000610368100035 |
Publication Date |
2020-12-08 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2040-3364 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
7.367 |
Times cited |
3 |
Open Access |
Not_Open_Access |
| Notes |
; ; |
Approved |
Most recent IF: 7.367 |
| Call Number |
UA @ admin @ c:irua:176141 |
Serial |
6690 |
| Permanent link to this record |
| |
|
| |
| Author |
Chen, X.; Li, L.; Peeters, F.M.; Sanyal, B. |
| Title |
Two-dimensional oxygen functionalized honeycomb and zigzag dumbbell silicene with robust Dirac cones |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
New Journal Of Physics |
Abbreviated Journal |
New J Phys |
| Volume |
23 |
Issue |
2 |
Pages |
023007 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Dumbbell-like structures are recently found to be energetically favored in group IV two-dimensional (2D) materials, exhibiting rich physics and many interesting properties. In this paper, using first-principles calculations, we have investigated the oxidized form of the hexagonal honeycomb (ODB-h) and zigzag dumbbell silicene (ODB-z). We confirm that both oxidization processes are energetically favorable, and their phonon spectra further demonstrate the dynamic stability. Contrary to the pristine dumbbell silicene structures (PDB-h and PDB-z silicene), these oxidized products ODB-h and ODB-z silicene are both semimetals with Dirac cones at the Fermi level. The Dirac cones of ODB-h and ODB-z silicene are at the K point and between Y and Gamma points respectively, possessing high Fermi velocities of 3.1 x 10(5) m s(-1) (ODB-h) and 2.9-3.4 x 10(5) m s(-1) (ODB-z). The origin of the Dirac cones is further explained by tight-binding models. The semimetallic properties of ODB-h and ODB-z are sensitive to compression due to the self-absorption effect, but quite robust against the tensile strain. These outstanding properties make oxidized dumbbell silicene a promising material for quantum computing and high-speed electronic devices. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000616114900001 |
Publication Date |
2021-01-14 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1367-2630 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.786 |
Times cited |
1 |
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 3.786 |
| Call Number |
UA @ admin @ c:irua:176575 |
Serial |
6741 |
| Permanent link to this record |
| |
|
| |
| Author |
Wang, J.; Van Pottelberge, R.; Jacobs, A.; Van Duppen, B.; Peeters, F.M. |
| Title |
Confinement and edge effects on atomic collapse in graphene nanoribbons |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
103 |
Issue |
3 |
Pages |
035426 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Atomic collapse in graphene nanoribbons behaves in a fundamentally different way as compared to monolayer graphene due to the presence of multiple energy bands and the effect of edges. For armchair nanoribbons we find that bound states gradually transform into atomic collapse states with increasing impurity charge. This is very different in zigzag nanoribbons where multiple quasi-one-dimensional bound states are found that originates from the zero-energy zigzag edge states. They are a consequence of the flat band and the electron distribution of these bound states exhibits two peaks. The lowest-energy edge state transforms from a bound state into an atomic collapse resonance and shows a distinct relocalization from the edge to the impurity position with increasing impurity charge. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000610779200008 |
Publication Date |
2021-01-22 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
8 |
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:176585 |
Serial |
6719 |
| Permanent link to this record |
| |
|
| |
| Author |
González-García, A.; López-Pérez, W.; González-Hernández, R.; Bacaksiz, C.; Šabani, D.; Milošević, M.V.; Peeters, F.M. |
| Title |
Transition-metal adatoms on 2D-GaAs: a route to chiral magnetic 2D materials by design |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Journal Of Physics-Condensed Matter |
Abbreviated Journal |
J Phys-Condens Mat |
| Volume |
33 |
Issue |
14 |
Pages |
145803 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Using relativistic density-functional calculations, we examine the magneto-crystalline anisotropy and exchange properties of transition-metal atoms adsorbed on 2D-GaAs. We show that single Mn and Mo atom (Co and Os) strongly bind on 2D-GaAs, and induce local out-of-plane (in-plane) magnetic anisotropy. When a pair of TM atoms is adsorbed on 2D-GaAs in a close range from each other, magnetisation properties change (become tunable) with respect to concentrations and ordering of the adatoms. In all cases, we reveal presence of strong Dzyaloshinskii–Moriya interaction. These results indicate novel pathways towards two-dimensional chiral magnetic materials by design, tailored for desired applications in magneto-electronics. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000626453600001 |
Publication Date |
2021-04-07 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
2.649 |
Times cited |
|
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 2.649 |
| Call Number |
CMT @ cmt @c:irua:177483 |
Serial |
6755 |
| Permanent link to this record |
| |
|
| |
| Author |
Hamid, I.; Jalali, H.; Peeters, F.M.; Neek-Amal, M. |
| Title |
Abnormal in-plane permittivity and ferroelectricity of confined water : from sub-nanometer channels to bulk |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Journal Of Chemical Physics |
Abbreviated Journal |
J Chem Phys |
| Volume |
154 |
Issue |
11 |
Pages |
114503 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Dielectric properties of nano-confined water are important in several areas of science, i.e., it is relevant in the dielectric double layer that exists in practically all heterogeneous fluid-based systems. Molecular dynamics simulations are used to predict the in-plane dielectric properties of confined water in planar channels of width ranging from sub-nanometer to bulk. Because of suppressed rotational degrees of freedom near the confining walls, the dipole of the water molecules tends to be aligned parallel to the walls, which results in a strongly enhanced in-plane dielectric constant (epsilon (parallel to)) reaching values of about 120 for channels with height 8 angstrom < h < 10 angstrom. With the increase in the width of the channel, we predict that epsilon (parallel to) decreases nonlinearly and reaches the bulk value for h > 70 angstrom. A stratified continuum model is proposed that reproduces the h > 10 angstrom dependence of epsilon (parallel to). For sub-nanometer height channels, abnormal behavior of epsilon (parallel to) is found with two orders of magnitude reduction of epsilon (parallel to) around h similar to 7.5 angstrom, which is attributed to the formation of a particular ice phase that exhibits long-time (similar to mu s) stable ferroelectricity. This is of particular importance for the understanding of the influence of confined water on the functioning of biological systems. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000629831900001 |
Publication Date |
2021-03-17 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0021-9606 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.965 |
Times cited |
9 |
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 2.965 |
| Call Number |
UA @ admin @ c:irua:177579 |
Serial |
6967 |
| Permanent link to this record |
| |
|
| |
| Author |
Conti, S.; Saberi-Pouya, S.; Perali, A.; Virgilio, M.; Peeters, F.M.; Hamilton, A.R.; Scappucci, G.; Neilson, D. |
| Title |
Electron-hole superfluidity in strained Si/Ge type II heterojunctions |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
npj Quantum Materials |
Abbreviated Journal |
|
| Volume |
6 |
Issue |
1 |
Pages |
41 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Excitons are promising candidates for generating superfluidity and Bose-Einstein condensation (BEC) in solid-state devices, but an enabling material platform with in-built band structure advantages and scaling compatibility with industrial semiconductor technology is lacking. Here we predict that spatially indirect excitons in a lattice-matched strained Si/Ge bilayer embedded into a germanium-rich SiGe crystal would lead to observable mass-imbalanced electron-hole superfluidity and BEC. Holes would be confined in a compressively strained Ge quantum well and electrons in a lattice-matched tensile strained Si quantum well. We envision a device architecture that does not require an insulating barrier at the Si/Ge interface, since this interface offers a type II band alignment. Thus the electrons and holes can be kept very close but strictly separate, strengthening the electron-hole pairing attraction while preventing fast electron-hole recombination. The band alignment also allows a one-step procedure for making independent contacts to the electron and hole layers, overcoming a significant obstacle to device fabrication. We predict superfluidity at experimentally accessible temperatures of a few Kelvin and carrier densities up to similar to 6 x 10(10) cm(-2), while the large imbalance of the electron and hole effective masses can lead to exotic superfluid phases. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000642904200001 |
Publication Date |
2021-04-23 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2397-4648 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
5 |
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ admin @ c:irua:178226 |
Serial |
6984 |
| Permanent link to this record |
| |
|
| |
| Author |
Baskurt, M.; Nair, R.R.; Peeters, F.M.; Sahin, H. |
| Title |
Ultra-thin structures of manganese fluorides : conversion from manganese dichalcogenides by fluorination |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Physical Chemistry Chemical Physics |
Abbreviated Journal |
Phys Chem Chem Phys |
| Volume |
23 |
Issue |
17 |
Pages |
10218-10224 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
In this study, it is predicted by density functional theory calculations that graphene-like novel ultra-thin phases of manganese fluoride crystals, that have nonlayered structures in their bulk form, can be stabilized by fluorination of manganese dichalcogenide crystals. First, it is shown that substitution of fluorine atoms with chalcogens in the manganese dichalcogenide host lattice is favorable. Among possible crystal formations, three stable ultra-thin structures of manganese fluoride, 1H-MnF2, 1T-MnF2 and MnF3, are found to be stable by total energy optimization calculations. In addition, phonon calculations and Raman activity analysis reveal that predicted novel single-layers are dynamically stable crystal structures displaying distinctive characteristic peaks in their vibrational spectrum enabling experimental determination of the corresponding phases. Differing from 1H-MnF2 antiferromagnetic (AFM) large gap semiconductor, 1T-MnF2 and MnF3 single-layers are semiconductors with ferromagnetic (FM) ground state. |
| Address |
|
| Corporate Author |
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Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000641719700001 |
Publication Date |
2021-04-15 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1463-9076; 1463-9084 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.123 |
Times cited |
1 |
Open Access |
Not_Open_Access |
| Notes |
|
Approved |
Most recent IF: 4.123 |
| Call Number |
UA @ admin @ c:irua:178252 |
Serial |
7043 |
| Permanent link to this record |
| |
|
| |
| Author |
Dehdast, M.; Valiollahi, Z.; Neek-Amal, M.; Van Duppen, B.; Peeters, F.M.; Pourfath, M. |
| Title |
Tunable natural terahertz and mid-infrared hyperbolic plasmons in carbon phosphide |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| Volume |
178 |
Issue |
|
Pages |
625-631 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Hyperbolic polaritons in ultra thin materials such as few layers of van derWaals heterostructures provide a unique control over light-matter interaction at the nanoscale and with various applications in flat optics. Natural hyperbolic surface plasmons have been observed on thin films of WTe2 in the light wavelength range of 16-23 mu m (similar or equal to 13-18 THz) [Nat. Commun. 11, 1158 (2020)]. Using time-dependent density functional theory, it is found that carbon doped monolayer phosphorene (beta-allotrope of carbon phosphide monolayer) exhibits natural hyperbolic plasmons at frequencies above similar or equal to 5 THz which is not observed in its parent materials, i.e. monolayer of black phosphorous and graphene. Furthermore, we found that by electrostatic doping the plasmonic frequency range can be extended to the mid-infrared. (C) 2021 Elsevier Ltd. All rights reserved. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000648729800057 |
Publication Date |
2021-03-26 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0008-6223 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.337 |
Times cited |
6 |
Open Access |
Not_Open_Access |
| Notes |
|
Approved |
Most recent IF: 6.337 |
| Call Number |
UA @ admin @ c:irua:179033 |
Serial |
7039 |
| Permanent link to this record |
| |
|
| |
| Author |
Varjovi, M.J.; Yagmurcukardes, M.; Peeters, F.M.; Durgun, E. |
| Title |
Janus two-dimensional transition metal dichalcogenide oxides: First-principles investigation of WXO monolayers with X = S, Se, and Te |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
103 |
Issue |
19 |
Pages |
195438 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Structural symmetry breaking in two-dimensional materials can lead to superior physical properties and introduce an additional degree of piezoelectricity. In the present paper, we propose three structural phases (1H, 1T, and 1T') of Janus WXO (X = S, Se, and Te) monolayers and investigate their vibrational, thermal, elastic, piezoelectric, and electronic properties by using first-principles methods. Phonon spectra analysis reveals that while the 1H phase is dynamically stable, the 1T phase exhibits imaginary frequencies and transforms to the distorted 1T' phase. Ab initio molecular dynamics simulations confirm that 1H- and 1T'-WXO monolayers are thermally stable even at high temperatures without any significant structural deformations. Different from binary systems, additional Raman active modes appear upon the formation of Janus monolayers. Although the mechanical properties of 1H-WXO are found to be isotropic, they are orientation dependent for 1T'-WXO. It is also shown that 1H-WXO monolayers are indirect band-gap semiconductors and the band gap narrows down the chalcogen group. Except 1T'-WSO, 1T'-WXO monolayers have a narrow band gap correlated with the Peierls distortion. The effect of spin-orbit coupling on the band structure is also examined for both phases and the alteration in the band gap is estimated. The versatile mechanical and electronic properties of Janus WXO monolayers together with their large piezoelectric response imply that these systems are interesting for several nanoelectronic applications. |
| Address |
|
| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000655902600004 |
Publication Date |
2021-05-26 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
48 |
Open Access |
Not_Open_Access |
| Notes |
|
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:179050 |
Serial |
7000 |
| Permanent link to this record |
| |
|
| |
| Author |
Pandey, T.; Covaci, L.; Milošević, M.V.; Peeters, F.M. |
| Title |
Flexoelectricity and transport properties of phosphorene nanoribbons under mechanical bending |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
103 |
Issue |
23 |
Pages |
235406 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We examine from first principles the flexoelectric properties of phosphorene nanoribbons under mechanical bending along armchair and zigzag directions. In both cases we find that the radial polarization depends linearly on the strain gradient. The flexoelectricity along the armchair direction is over 40% larger than along the zigzag direction. The obtained flexoelectric coefficients of phosphorene are four orders of magnitude larger than those of graphene and comparable to transition metal dichalcogenides. Analysis of charge density shows that the flexoelectricity mainly arises from the pz orbitals of phosphorus atoms. The electron mobilities in bent phosphorene can be enhanced by over 60% along the armchair direction, which is significantly higher than previous reports of mobility tuned by uniaxial strain. Our results indicate phosphorene is a candidate for a two-dimensional material applicable in flexible-electronic devices. |
| Address |
|
| Corporate Author |
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Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000657129800006 |
Publication Date |
2021-06-02 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
8 |
Open Access |
Not_Open_Access |
| Notes |
|
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:179109 |
Serial |
6996 |
| Permanent link to this record |
| |
|
| |
| Author |
Lyu, Y.-Y.; Jiang, J.; Wang, Y.-L.; Xiao, Z.-L.; Dong, S.; Chen, Q.-H.; Milošević, M.V.; Wang, H.; Divan, R.; Pearson, J.E.; Wu, P.; Peeters, F.M.; Kwok, W.-K. |
| Title |
Superconducting diode effect via conformal-mapped nanoholes |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Nature Communications |
Abbreviated Journal |
Nat Commun |
| Volume |
12 |
Issue |
1 |
Pages |
2703 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
A superconducting diode is an electronic device that conducts supercurrent and exhibits zero resistance primarily for one direction of applied current. Such a dissipationless diode is a desirable unit for constructing electronic circuits with ultralow power consumption. However, realizing a superconducting diode is fundamentally and technologically challenging, as it usually requires a material structure without a centre of inversion, which is scarce among superconducting materials. Here, we demonstrate a superconducting diode achieved in a conventional superconducting film patterned with a conformal array of nanoscale holes, which breaks the spatial inversion symmetry. We showcase the superconducting diode effect through switchable and reversible rectification signals, which can be three orders of magnitude larger than that from a flux-quantum diode. The introduction of conformal potential landscapes for creating a superconducting diode is thereby proven as a convenient, tunable, yet vastly advantageous tool for superconducting electronics. This could be readily applicable to any superconducting materials, including cuprates and iron-based superconductors that have higher transition temperatures and are desirable in device applications. A superconducting diode is dissipationless and desirable for electronic circuits with ultralow power consumption, yet it remains challenging to realize it. Here, the authors achieve a superconducting diode in a conventional superconducting film patterned with a conformal array of nanoscale holes. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000658724200018 |
Publication Date |
2021-05-11 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2041-1723 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
12.124 |
Times cited |
23 |
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 12.124 |
| Call Number |
UA @ admin @ c:irua:179611 |
Serial |
7024 |
| Permanent link to this record |
| |
|
| |
| Author |
Conti, S.; Perali, A.; Peeters, F.M.; Neilson, D. |
| Title |
Effect of mismatched electron-hole effective masses on superfluidity in double layer solid-state systems |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Condensed Matter |
Abbreviated Journal |
|
| Volume |
6 |
Issue |
2 |
Pages |
14 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Superfluidity has been predicted and now observed in a number of different electron-hole double-layer semiconductor heterostructures. In some of the heterostructures, such as GaAs and Ge-Si electron-hole double quantum wells, there is a strong mismatch between the electron and hole effective masses. We systematically investigate the sensitivity to unequal masses of the superfluid properties and the self-consistent screening of the electron-hole pairing interaction. We find that the superfluid properties are insensitive to mass imbalance in the low density BEC regime of strongly-coupled boson-like electron-hole pairs. At higher densities, in the BEC-BCS crossover regime of fermionic pairs, we find that mass imbalance between electrons and holes weakens the superfluidity and expands the density range for the BEC-BCS crossover regime. This permits screening to kill the superfluid at a lower density than for equal masses. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000665155800001 |
Publication Date |
2021-04-07 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2410-3896 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
1 |
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ admin @ c:irua:179635 |
Serial |
6982 |
| Permanent link to this record |
| |
|
| |
| Author |
Miranda, L.P.; Milovanović, S.P.; Filho, R.N.C.; Peeters, F.M. |
| Title |
Hall and bend resistance of a phosphorene Hall bar |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
104 |
Issue |
3 |
Pages |
035401 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The dependence of the Hall and bend resistances on a perpendicular magnetic field and on vacancy defects in a four-terminal phosphorene single layer Hall bar is investigated. A tight-binding model in combination with the Landauer-Buttiker formalism is used to calculate the energy spectrum, the lead-to-lead transmissions, and the Hall and bend resistances of the system. It is shown that the terminals with zigzag edge orientation are responsible for the absence of quantized plateaus in the Hall resistance and peaks in the longitudinal resistance. A negative bend resistance in the ballistic regime is found due to the presence of high- and low-energy transport modes in the armchair and zigzag terminals, respectively. The system density of states, with single vacancy defects, shows that the presence of in-gap states is proportional to the number of vacancies. Quantized plateaus in the Hall resistance are only formed in a sufficiently clean system. The effects of different kinds of vacancies where the plateaus are destroyed and a diffusive regime appears in the bend resistance are investigated. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000669002000003 |
Publication Date |
2021-07-01 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
2 |
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:179704 |
Serial |
6997 |
| Permanent link to this record |
| |
|
| |
| Author |
Chaves, A.; Peeters, F.M. |
| Title |
Tunable effective masses of magneto-excitons in two-dimensional materials |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Solid State Communications |
Abbreviated Journal |
Solid State Commun |
| Volume |
334 |
Issue |
|
Pages |
114371 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Excitonic properties of Ge2H2 and Sn2H2, also known as Xanes, are investigated within the effective mass model. A perpendicularly applied magnetic field induces a negative shift on the exciton center-of-mass kinetic energy that is approximately quadratic with its momentum, thus pushing down the exciton dispersion curve and flattening it. This can be interpreted as an increase in the effective mass of the magneto-exciton, tunable by the field intensity. Our results show that in low effective mass two-dimensional semiconductors, such as Xanes, the applied magnetic field allows one to tune the magneto-exciton effective mass over a wide range of values. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000670329600003 |
Publication Date |
2021-05-14 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0038-1098 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
1.554 |
Times cited |
|
Open Access |
Not_Open_Access |
| Notes |
|
Approved |
Most recent IF: 1.554 |
| Call Number |
UA @ admin @ c:irua:179762 |
Serial |
7037 |
| Permanent link to this record |
| |
|
| |
| Author |
Nazar, N.D.; Vazifehshenas, T.; Ebrahimi, M.R.; Peeters, F.M. |
| Title |
Strong anisotropic optical properties of 8-Pmmn borophene : a many-body perturbation study |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Physical Chemistry Chemical Physics |
Abbreviated Journal |
Phys Chem Chem Phys |
| Volume |
23 |
Issue |
30 |
Pages |
16417-16422 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Using first-principles many-body perturbation theory, we investigate the optical properties of 8-Pmmn borophene at two levels of approximations; the GW method considering only the electron-electron interaction and the GW in combination with the Bethe-Salpeter equation including electron-hole coupling. The band structure exhibits anisotropic Dirac cones with semimetallic character. The optical absorption spectra are obtained for different light polarizations and we predict strong optical absorbance anisotropy. The absorption peaks undergo a global redshift when the electron-hole interaction is taken into account due to the formation of bound excitons which have an anisotropic excitonic wave function. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000677722700001 |
Publication Date |
2021-07-21 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1463-9076; 1463-9084 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
4.123 |
Times cited |
|
Open Access |
Not_Open_Access |
| Notes |
|
Approved |
Most recent IF: 4.123 |
| Call Number |
UA @ admin @ c:irua:180385 |
Serial |
7022 |
| Permanent link to this record |
| |
|
| |
| Author |
Yagmurcukardes, M.; Mogulkoc, Y.; Akgenc, B.; Mogulkoc, A.; Peeters, F.M. |
| Title |
Prediction of monoclinic single-layer Janus Ga₂ Te X (X = S and Se) : strong in-plane anisotropy |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
104 |
Issue |
4 |
Pages |
045425 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
By using density functional theory (DFT) based first-principles calculations, electronic, vibrational, piezo-electric, and optical properties of monoclinic Janus single-layer Ga2TeX (X = S or Se) are investigated. The dynamical, mechanical, and thermal stability of the proposed Janus single layers are verified by means of phonon bands, stiffness tensor, and quantum molecular dynamics simulations. The calculated vibrational spectrum reveals the either pure or coupled optical phonon branches arising from Ga-Te and Ga-X atoms. In addition to the in-plane anisotropy, single-layer Janus Ga2TeX exhibits additional out-of-plane asymmetry, which leads to important consequences for its electronic and optical properties. Electronic band dispersions indicate the direct band-gap semiconducting nature of the constructed Janus structures with energy band gaps falling into visible spectrum. Moreover, while orientation-dependent linear-elastic properties of Janus single layers indicate their strong anisotropy, the calculated in-plane stiffness values reveal the ultrasoft nature of the structures. In addition, predicted piezoelectric coefficients show that while there is a strong in-plane anisotropy between piezoelectric constants along armchair (AC) and zigzag (ZZ) directions, there exists a tiny polarization along the out-of-plane direction as a result of the formation of Janus structure. The optical response to electromagnetic radiation has been also analyzed through density functional theory by considering the independent-particle approximation. Finally, the optical spectra of Janus Ga2TeX structures is investigated and it showed a shift from the ultraviolet region to the visible region. The fact that the spectrum is between these regions will allow it to be used in solar energy and many nanoelectronics applications. The predicted monoclinic single-layer Janus Ga2TeX are relevant for promising applications in optoelectronics, optical dichroism, and anisotropic nanoelasticity. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000678811100007 |
Publication Date |
2021-07-26 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
3 |
Open Access |
Not_Open_Access |
| Notes |
|
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:180404 |
Serial |
7013 |
| Permanent link to this record |
| |
|
| |
| Author |
Akbali, B.; Yagmurcukardes, M.; Peeters, F.M.; Lin, H.-Y.; Lin, T.-Y.; Chen, W.-H.; Maher, S.; Chen, T.-Y.; Huang, C.-H. |
| Title |
Determining the molecular orientation on the metal nanoparticle surface through surface-enhanced Raman spectroscopy and density functional theory simulations |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Journal Of Physical Chemistry C |
Abbreviated Journal |
J Phys Chem C |
| Volume |
125 |
Issue |
29 |
Pages |
16289-16295 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
We report here the efficacy of surface-enhanced Raman spectroscopy (SERS) measurements as a probe for molecular orientation. 4-Aminobenzoic acid (PABA) on a surface consisting of silver (Ag) nanoparticles (NPs) is investigated. We find that the orientation of the PABA molecule on the SERS substrate is estimated based on the relative change in the magnitude of the C-H stretching bands on the SERS substrate, and it is found that the molecule assumes a horizontal orientation on the Ag-NP surface. The strong molecule-metal interaction is determined by an abnormal enhanced SERS band appearing at 980 cm(-1), and the peak is assigned to an out-of-plane amine vibrational mode, which is supported by our ab initio calculations. DFT-based Raman activity calculations corroborate the SERS results, revealing that (i) the PABA molecule attaches to the surface of Ag-NPs with its alpha dimers rather than single-molecule binding and (ii) the molecule preserves its alpha dimers in an aqueous environment. Our results demonstrate that SERS can be used to gain deeper insights into the molecular orientation on metal nanoparticle surfaces. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000680445800055 |
Publication Date |
2021-07-19 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1932-7447; 1932-7455 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4.536 |
Times cited |
2 |
Open Access |
Not_Open_Access |
| Notes |
|
Approved |
Most recent IF: 4.536 |
| Call Number |
UA @ admin @ c:irua:180455 |
Serial |
6978 |
| Permanent link to this record |
| |
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| |
| Author |
Cunha, S.M.; de Costa, D.R.; Pereira Jr, J.M.; Costa Filho, R.N.; Van Duppen, B.; Peeters, F.M. |
| Title |
Band-gap formation and morphing in alpha-T-3 superlattices |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
104 |
Issue |
11 |
Pages |
115409 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Electrons in alpha-T-3 lattices behave as condensed-matter analogies of integer-spin Dirac fermions. The three atoms making up the unit cell bestow the energy spectrum with an additional energy band that is completely flat, providing unique electronic properties. The interatomic hopping term, alpha, is known to strongly affect the electronic spectrum of the two-dimensional (2D) lattice, allowing it to continuously morph from graphenelike responses to the behavior of fermions in a dice lattice. For pristine lattice structures the energy bands are gapless, but small deviations in the atomic equivalence of the three sublattices will introduce gaps in the spectrum. It is unknown how these affect transport and electronic properties such as the energy spectrum of superlattice minibands. Here we investigate the dependency of these properties on the parameter a accounting for different symmetry-breaking terms, and we show how it affects band-gap formation. Furthermore, we find that superlattices can force band gaps to close and shift in energy. Our results demonstrate that alpha-T-3 superlattices provide a versatile material for 2D band-gap engineering purposes. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000696091600003 |
Publication Date |
2021-09-10 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
6 |
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:181544 |
Serial |
6972 |
| Permanent link to this record |
| |
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| |
| Author |
Lavor, I.R.; da Costa, D.R.; Covaci, L.; Milošević, M.V.; Peeters, F.M.; Chaves, A. |
| Title |
Zitterbewegung of moiré excitons in twisted MoS₂/WSe₂ heterobilayers |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Physical review letters |
Abbreviated Journal |
|
| Volume |
127 |
Issue |
10 |
Pages |
106801 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
| Abstract |
The moire pattern observed in stacked noncommensurate crystal lattices, such as heterobilayers of transition metal dichalcogenides, produces a periodic modulation of their band gap. Excitons subjected to this potential landscape exhibit a band structure that gives rise to a quasiparticle dubbed the moire exciton. In the case of MoS2/WSe2 heterobilayers, the moire trapping potential has honeycomb symmetry and, consequently, the moire exciton band structure is the same as that of a Dirac-Weyl fermion, whose mass can be further tuned down to zero with a perpendicularly applied field. Here we show that, analogously to other Dirac-like particles, the moire exciton exhibits a trembling motion, also known as Zitterbewegung, whose long timescales are compatible with current experimental techniques for exciton dynamics. This promotes the study of the dynamics of moire excitons in van der Waals heterostructures as an advantageous solid-state platform to probe Zitterbewegung, broadly tunable by gating and interlayer twist angle. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Wos |
000692200800020 |
Publication Date |
2021-08-31 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1079-7114 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
|
Times cited |
4 |
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ admin @ c:irua:181599 |
Serial |
6896 |
| Permanent link to this record |
| |
|
| |
| Author |
Zou, Y.-C.; Mogg, L.; Clark, N.; Bacaksiz, C.; Milanovic, S.; Sreepal, V.; Hao, G.-P.; Wang, Y.-C.; Hopkinson, D.G.; Gorbachev, R.; Shaw, S.; Novoselov, K.S.; Raveendran-Nair, R.; Peeters, F.M.; Lozada-Hidalgo, M.; Haigh, S.J. |
| Title |
Ion exchange in atomically thin clays and micas |
Type |
A1 Journal article |
| Year |
2021 |
Publication |
Nature Materials |
Abbreviated Journal |
Nat Mater |
| Volume |
20 |
Issue |
12 |
Pages |
1677-1682 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The physical properties of clays and micas can be controlled by exchanging ions in the crystal lattice. Atomically thin materials can have superior properties in a range of membrane applications, yet the ion-exchange process itself remains largely unexplored in few-layer crystals. Here we use atomic-resolution scanning transmission electron microscopy to study the dynamics of ion exchange and reveal individual ion binding sites in atomically thin and artificially restacked clays and micas. We find that the ion diffusion coefficient for the interlayer space of atomically thin samples is up to 10(4) times larger than in bulk crystals and approaches its value in free water. Samples where no bulk exchange is expected display fast exchange at restacked interfaces, where the exchanged ions arrange in islands with dimensions controlled by the moire superlattice dimensions. We attribute the fast ion diffusion to enhanced interlayer expandability resulting from weaker interlayer binding forces in both atomically thin and restacked materials. This work provides atomic scale insights into ion diffusion in highly confined spaces and suggests strategies to design exfoliated clay membranes with enhanced performance. Layered clays are of interest for membranes and many other applications but their ion-exchange dynamics remain unexplored in atomically thin materials. Here, using electron microscopy, it is found that the ion diffusion for few-layer two-dimensional clays approaches that of free water and that superlattice cation islands can form in twisted and restacked materials. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000689664000001 |
Publication Date |
2021-09-21 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1476-1122; 1476-4660 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
39.737 |
Times cited |
|
Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 39.737 |
| Call Number |
UA @ admin @ c:irua:181691 |
Serial |
6999 |
| Permanent link to this record |
