| Records |
| Author |
Bekaert, J.; Petrov, M.; Aperis, A.; Oppeneer, P.M.; Milošević, M.V. |
| Title |
Hydrogen-induced high-temperature superconductivity in two-dimensional materials : the example of hydrogenated monolayer MgB2 |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
| Volume |
123 |
Issue |
7 |
Pages |
077001 |
Keywords  |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Hydrogen-based compounds under ultrahigh pressure, such as the polyhydrides H3S and LaH10, superconduct through the conventional electron-phonon coupling mechanism to attain the record critical temperatures known to date. Here we exploit the intrinsic advantages of hydrogen to strongly enhance phonon-mediated superconductivity in a completely different system, namely, a two-dimensional material with hydrogen adatoms. We find that van Hove singularities in the electronic structure, originating from atomiclike hydrogen states, lead to a strong increase of the electronic density of states at the Fermi level, and thus of the electron-phonon coupling. Additionally, the emergence of high-frequency hydrogen-related phonon modes in this system boosts the electron-phonon coupling further. As a concrete example, we demonstrate the effect of hydrogen adatoms on the superconducting properties of monolayer MgB2, by solving the fully anisotropic Eliashberg equations, in conjunction with a first-principles description of the electronic and vibrational states, and their coupling. We show that hydrogenation leads to a high critical temperature of 67 K, which can be boosted to over 100 K by biaxial tensile strain. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000480611900017 |
Publication Date |
2019-08-14 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0031-9007 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
8.462 |
Times cited |
42 |
Open Access |
|
| Notes |
; This work was supported by TOPBOF-UAntwerp, Research Foundation-Flanders (FWO), the Swedish Research Council (VR), the Rontgen-Angstrom Cluster, and the EU-COST Action CA16218. J.B. 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. Eliashberg theory calculations were supported through the Swedish National Infrastructure for Computing (SNIC). We would also like to acknowledge useful discussions with Bart Partoens, Jacques Tempere, and Matthieu Verstraete. ; |
Approved |
Most recent IF: 8.462 |
| Call Number |
UA @ admin @ c:irua:161816 |
Serial |
5415 |
| Permanent link to this record |
| |
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| |
| Author |
Houben, K.; Jochum, J.K.; Lozano, D.P.; Bisht, M.; Menendez, E.; Merkel, D.G.; Ruffer, R.; Chumakov, A., I; Roelants, S.; Partoens, B.; Milošević, M.V.; Peeters, F.M.; Couet, S.; Vantomme, A.; Temst, K.; Van Bael, M.J. |
| Title |
In situ study of the \alpha-Sn to \beta-Sn phase transition in low-dimensional systems : phonon behavior and thermodynamic properties |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
100 |
Issue |
7 |
Pages |
075408 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The densities of phonon states of thin Sn films on InSb substrates are determined during different stages of the alpha-Sn to beta-Sn phase transition using nuclear inelastic x-ray scattering. The vibrational entropy and internal energy per atom as a function of temperature are obtained by numerical integration of the phonon density of states. The free energy as a function of temperature for the nanoscale samples is compared to the free energy obtained from ab initio calculations of bulk tin in the alpha-Sn and beta-Sn phase. In thin films this phase transition is governed by the interplay between the vibrational behavior of the film (the phase transition is driven by the vibrational entropy) and the stabilizing influence of the substrate (which depends on the film thickness). This brings a deeper understanding of the role of lattice vibrations in the phase transition of nanoscale Sn. |
| 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 |
000478992800005 |
Publication Date |
2019-08-08 |
| 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 |
9 |
Open Access |
|
| Notes |
; This work was supported by the Research Foundation Flanders (FWO) and the Concerted Research Action (Grant No. GOA14/007). K.H., S.C., D.P.L., and E.M. wish to thank the FWO for financial support. The authors gratefully acknowledge the European Synchrotron Radiation Facility (ESRF) for the granted beam time and the use of the in situ UHV preparation chamber. The authors thank B. Opperdoes for technical support and T. Peissker and R. Lieten for fruitful discussions. ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:161836 |
Serial |
5416 |
| Permanent link to this record |
| |
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| |
| Author |
Chen, Q.; Li, L.L.; Peeters, F.M. |
| Title |
Inner and outer ring states of MoS2 quantum rings : energy spectrum, charge and spin currents |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| Volume |
125 |
Issue |
24 |
Pages |
244303 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We investigate the energy levels and persistent currents of MoS2 quantum rings having different shapes and edge types in the presence of a perpendicular magnetic field by means of the tight-binding approach. We find states localized at the inner and outer boundaries of the ring. These energy levels exhibit different magnetic field dependences for the inner and outer ring states due to their different localization properties. They both exhibit the usual Aharanov-Bohm oscillations but with different oscillation periods. In the presence of spin-orbit coupling, we show distinct spin and charge persistent currents for inner and outer ring states. We find well-defined spin currents with negligibly small charge currents. This is because the local currents of spin-up and -down states flow in opposite directions. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000474439600026 |
Publication Date |
2019-06-25 |
| 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 |
2.068 |
Times cited |
11 |
Open Access |
|
| Notes |
; This work was supported by the Hunan Provincial Natural Science Foundation of China (Nos. 2015JJ2040, 2018JJ2080, and 2018JJ4047), the National Natural Science Foundation of China (NNSFC) (No. 51502087), the Scientific Research Fund of Hunan Provincial Education Department (Nos. 15A042, 15B056, and 17B060), and the Flemish Science Foundation (FWO-VI). ; |
Approved |
Most recent IF: 2.068 |
| Call Number |
UA @ admin @ c:irua:161309 |
Serial |
5417 |
| Permanent link to this record |
| |
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| |
| Author |
Bafekry, A.; Shayesteh, S.F.; Peeters, F.M. |
| Title |
Introducing novel electronic and magnetic properties in C3N nanosheets by defect engineering and atom substitution |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
| Volume |
21 |
Issue |
37 |
Pages |
21070-21083 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Using first-principles calculations the effect of topological defects, vacancies, Stone-Wales and anti-site and substitution of atoms, on the structure and electronic properties of monolayer C3N are investigated. Vacancy defects introduce localized states near the Fermi level and a local magnetic moment. While pristine C3N is an indirect semiconductor with a 0.4 eV band gap, with substitution of O, S and Si atoms for C, it remains a semiconductor with a band gap in the range 0.25-0.75 eV, while it turns into a metal with H, Cl, B, P, Li, Na, K, Be and Mg substitution. With F substitution, it becomes a dilute-magnetic semiconductor, while with Ca substitution it is a ferromagnetic-metal. When replacing the N host atom, C3N turns into: a metal (H, O, S, C, Si, P, Li and Be), ferromagnetic-metal (Mg), half-metal (Ca) and spin-glass semiconductor (Na and K). Moreover, the effects of charging and strain on the electronic properties of Na atom substitution in C3N are investigated. We found that the magnetic moment decreases or increases depending on the type and size of strain (tensile or compression). Our study shows how the band gap and magnetism in monolayer C3N can be tuned by introducing defects and atom substitution. The so engineered C3N can be a good candidate for future low dimensional devices. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000489984200050 |
Publication Date |
2019-09-09 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| 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 |
59 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 4.123 |
| Call Number |
UA @ admin @ c:irua:163732 |
Serial |
5418 |
| Permanent link to this record |
| |
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| |
| Author |
Menezes, R.M.; Neto, J.F.S.; de Souza Silva, C.C.; Milošević, M.V. |
| Title |
Manipulation of magnetic skyrmions by superconducting vortices in ferromagnet-superconductor heterostructures |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
100 |
Issue |
1 |
Pages |
014431 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Dynamics of magnetic skyrmions in hybrid ferromagnetic films harbors interesting physical phenomena and holds promise for technological applications. In this work, we discuss the behavior of magnetic skyrmions when coupled to superconducting vortices in a ferromagnet-superconductor heterostructure. We use numerical simulations and analytic arguments within London and Thiele formalisms to reveal broader possibilities for manipulating the skyrmion-vortex dynamic correlations in the hybrid system, that are not possible in its separated constituents. We explore the thresholds of particular dynamic phases, and quantify the phase diagram as a function of the relevant material parameters, applied current, and induced magnetic torques. Finally, we demonstrate the broad and precise tunability of the skyrmion Hall angle in the presence of vortices, with respect to currents applied to either or both the superconductor and the ferromagnet within the heterostructure. |
| 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 |
000477883500004 |
Publication Date |
2019-07-29 |
| 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 |
17 |
Open Access |
|
| Notes |
; This work was supported by the Research Foundation – Flanders (FWO-Vlaanderen) and Brazilian Agencies Fundacao de Amparo a Ciencia e Tecnologia do Estado de Pernambuco (FACEPE, under Grant No. APQ-0198-1.05/14), Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES), and Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq). ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:161890 |
Serial |
5421 |
| Permanent link to this record |
| |
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| |
| Author |
Van Pottelberge, R.; Moldovan, D.; Milovanović, S.P.; Peeters, F.M. |
| Title |
Molecular collapse in monolayer graphene |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
| Volume |
6 |
Issue |
4 |
Pages |
045047 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Atomic collapse is a phenomenon inherent to relativistic quantum mechanics where electron states dive in the positron continuum for highly charged nuclei. This phenomenon was recently observed in graphene. Here we investigate a novel collapse phenomenon when multiple sub- and supercritical charges of equal strength are put close together as in a molecule. We construct a phase diagram which consists of three distinct regions: (1) subcritical, (2) frustrated atomic collapse, and (3) molecular collapse. We show that the single impurity atomic collapse resonances rearrange themselves to form molecular collapse resonances which exhibit a distinct bonding, anti-bonding and non-bonding character. Here we limit ourselves to systems consisting of two and three charges. We show that by tuning the distance between the charges and their strength a high degree of control over the molecular collapse resonances can be achieved. |
| 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 |
000487692200003 |
Publication Date |
2019-08-30 |
| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
6.937 |
Times cited |
10 |
Open Access |
|
| Notes |
; We thank Matthias Van der Donck for fruitful discussions. This work was supported by the Research Foundation of Flanders (FWO-V1) through an aspirant research Grant for RVP and a postdoctoral Grant for SPM. ; |
Approved |
Most recent IF: 6.937 |
| Call Number |
UA @ admin @ c:irua:163756 |
Serial |
5422 |
| Permanent link to this record |
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| |
| Author |
Yagmurcukardes, M. |
| Title |
Monolayer fluoro-InSe : formation of a thin monolayer via fluorination of InSe |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
100 |
Issue |
2 |
Pages |
024108 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
By performing density functional theory-based first-principles calculations, the formation of a thin monolayer structure, namely InSeF, via fluorination of monolayer InSe is predicted. It is shown that strong interaction of F and In atoms leads to the detachment of In-Se layers in monolayer InSe and 1T-like monolayer InSeF structure is formed. Monolayer InSeF is found to be dynamically stable in terms of its phonon band dispersions. In addition, its Raman spectrum is shown to exhibit totally distinctive features as compared to monolayer InSe. The electronic band dispersions reveal that monolayer InSeF is a direct gap semiconductor whose valence and conduction band edges reside at the Gamma point. Moreover, the orientation-dependent linear elastic properties of monolayer InSeF are investigated in terms of the in-plane stiffness and Poisson ratio. It is found that monolayer InSeF displays strong in-plane anisotropy in elastic constants and it is slightly softer material as compared to monolayer InSe. Overall, it is proposed that a thin, direct gap semiconducting monolayer InSeF can be formed by full fluorination of monolayer InSe as a new member of the two-dimensional family. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000477885700003 |
Publication Date |
2019-07-29 |
| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
9 |
Open Access |
|
| Notes |
; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). This work is supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship (M.Y.). ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:161891 |
Serial |
5423 |
| Permanent link to this record |
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| |
| Author |
Yuan, H.F.; Xu, W.; Zhao, X.N.; Song, D.; Zhang, G.R.; Xiao, Y.M.; Ding, L.; Peeters, F.M. |
| Title |
Quantum and transport mobilities of a Na3Bi-based three-dimensional Dirac system |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
99 |
Issue |
23 |
Pages |
235303 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The electronic and transport properties of a three-dimensional (3D) Dirac system are investigated theoretically, which is motivated by recent experimental measurements on quantum and transport mobilities in the 3D Dirac semimetal Na3Bi by J. Xiong et al. [Science 350, 413 (2015); Europhys. Lett. 114, 27002 (2016)]. The electron Hamiltonian is taken from a simplified k center dot p approach. From the obtained electronic band structure and the Fermi energy, we explain why the anomalous effect induced by the chiral anomaly and the Berry curvature in the energy band can be observed experimentally in magnetotransport coefficients in both low-and high-density samples. Moreover, the quantum and transport mobilities are calculated on the basis of the momentum-balance equation derived from a semiclassical Boltzmann equation with the electron-impurity interaction. The quantum and transport mobilities obtained from this study agree both qualitatively and quantitatively with those measured experimentally. We also examine the electron mobilities along different crystal directions in Na3Bi and find them largely anisotropic. The theoretical findings from this work can be helpful in gaining an in-depth understanding of the experimental results and of the basic electronic and transport properties of newly developed 3D Dirac systems. |
| 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 |
000471983500006 |
Publication Date |
2019-06-17 |
| 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 |
|
| 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 |
|
| Notes |
; ; |
Approved |
Most recent IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:161329 |
Serial |
5425 |
| Permanent link to this record |
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| |
| Author |
Nakhaee, M.; Yagmurcukardes, M.; Ketabi, S.A.; Peeters, F.M. |
| Title |
Single-layer structures of a100- and b010-Gallenene : a tight-binding approach |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
| Volume |
21 |
Issue |
28 |
Pages |
15798-15804 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Using the simplified linear combination of atomic orbitals (LCAO) method in combination with ab initio calculations, we construct a tight-binding (TB) model for two different crystal structures of monolayer gallium: a(100)- and b(010)-Gallenene. The analytical expression for the Hamiltonian and numerical results for the overlap matrix elements between different orbitals of the Ga atoms and for the Slater and Koster (SK) integrals are obtained. We find that the compaction of different structures affects significantly the formation of the orbitals. The results for a(100)-Gallenene can be very well explained with an orthogonal basis set, while for b(010)-Gallenene we have to assume a non-orthogonal basis set in order to construct the TB model. Moreover, the transmission properties of nanoribbons of both monolayers oriented along the AC and ZZ directions are also investigated and it is shown that both AC- and ZZ-b(010)-Gallenene nanoribbons exhibit semiconducting behavior with zero transmission while those of a(100)-Gallenene nanoribbons are metallic. |
| 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 |
000476603700057 |
Publication Date |
2019-06-27 |
| 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 |
| Impact Factor |
4.123 |
Times cited |
14 |
Open Access |
|
| Notes |
; This work is supported by the Methusalem program of the Flemish government and the FLAG-ERA project TRANS-2D-TMD. This work is supported by the Flemish Science Foundation (FWO-Vl) by a post-doctoral fellowship (M. Y.). M. N. is partially supported by BFO (Uantwerpen). ; |
Approved |
Most recent IF: 4.123 |
| Call Number |
UA @ admin @ c:irua:161881 |
Serial |
5427 |
| Permanent link to this record |
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| |
| Author |
Li, L.L.; Peeters, F.M. |
| Title |
Strain engineered linear dichroism and Faraday rotation in few-layer phosphorene |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
114 |
Issue |
24 |
Pages |
243102 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We investigate theoretically the linear dichroism and the Faraday rotation of strained few-layer phosphorene, where strain is applied uniaxially along the armchair or zigzag direction of the phosphorene lattice. We calculate the optical conductivity tensor of uniaxially strained few-layer phosphorene by means of the Kubo formula within the tight-binding approach. We show that the linear dichroism and the Faraday rotation of few-layer phosphorene can be significantly modulated by the applied strain. The modulation depends strongly on both the magnitude and direction of strain and becomes more pronounced with increasing number of phosphorene layers. Our results are relevant for mechano-optoelectronic applications based on optical absorption and Hall effects in strained few-layer phosphorene. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000472599100029 |
Publication Date |
2019-06-17 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
|
| ISSN |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.411 |
Times cited |
12 |
Open Access |
|
| Notes |
; This work was financially supported by the Flemish Science Foundation (FWO-Vl) and by the FLAG-ERA Project TRANS-2D-TMD. ; |
Approved |
Most recent IF: 3.411 |
| Call Number |
UA @ admin @ c:irua:161327 |
Serial |
5428 |
| Permanent link to this record |
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| |
| Author |
Bafekry, A.; Ghergherehchi, M.; Shayesteh, S.F. |
| Title |
Tuning the electronic and magnetic properties of antimonene nanosheets via point defects and external fields: first-principles calculations |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
| Volume |
21 |
Issue |
20 |
Pages |
10552-10566 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Defects are inevitably present in materials, and their existence in a material strongly affects its fundamental physical properties. We have systematically investigated the effects of surface adsorption, substitutional impurities, defect engineering, an electric field and strain engineering on the structural, electronic and magnetic properties of antimonene nanosheets, using spin-polarized density functional calculations based on first-principles. The adsorption or substitution of atoms can locally modify the atomic and electronic structures as well as induce a variety of electronic behaviors including metal, half-metal, ferromagnetic metal, dilute magnetic semiconductor and spin-glass semiconductor. Our calculations show that the presence of typical defects (vacancies and Stone-Wales defect) in antimonene affects the geometrical symmetry as well as the band gap in the electronic band structure and induces magnetism to antimonene. Moreover, by applying an external electric field and strain (uniaxial and biaxial), the electronic structure of antimonene can be easily modified. The calculation results presented in this paper provide a fundamental insight into the tunable nature of the electronic properties of antimonene, supporting its promise for use in future applications. |
| 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 |
000476561000031 |
Publication Date |
2019-04-25 |
| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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| 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 |
17 |
Open Access |
|
| Notes |
; ; |
Approved |
Most recent IF: 4.123 |
| Call Number |
UA @ admin @ c:irua:161945 |
Serial |
5430 |
| Permanent link to this record |
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| |
| Author |
Bafekry, A.; Stampfl, C.; Ghergherehchi, M.; Shayesteh, S.F. |
| Title |
A first-principles study of the effects of atom impurities, defects, strain, electric field and layer thickness on the electronic and magnetic properties of the C2N nanosheet |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| Volume |
157 |
Issue |
157 |
Pages |
371-384 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Using the first-principles calculations, we explore the structural and novel electronic/optical properties of the C2N nanosheet. To this goal, we systematically investigate the affect of layer thickness, electrical field and strain on the electronic properties of the C2N nanosheet. By increasing the thickness of C2N, we observed that the band gap decreases. Moreover, by applying an electrical field to bilayer C2N, the band gap decreases and a semiconductor-to-metal transition can occur. Our results also confirm that uniaxial and biaxial strain can effectively alter the band gap of C2N monolayer. Furthermore, we show that the electronic and magnetic properties of C2N can be modified by the adsorption and substitution of various atoms. Depending on the species of embedded atoms, they may induce semiconductor (O, C, Si and Be), metal (S, N, P, Na, K, Mg and Ca), dilute-magnetic semiconductor (H, F, B), or ferro-magnetic-metal (Cl, Li) character in C2N monolayer. It was also found that the inclusion of hydrogen or oxygen impurities and nitrogen vacancies, can induce magnetism in the C2N monolayer. These extensive calculations can be useful to guide future studies to modify the electronic/optical properties of two-dimensional materials. (C) 2019 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 |
000502548500044 |
Publication Date |
2019-10-22 |
| 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 |
49 |
Open Access |
|
| Notes |
; This work was supported by the National Research Foundation of Korea grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). We are thankful for comments by Meysam Baghery Tagani from department of physics in University of Guilan and Bohayra Mortazavi from Gottfried Wilhelm Leibniz Universitat Hannover, Hannover, Germany. ; |
Approved |
Most recent IF: 10.9; 2020 IF: 6.337 |
| Call Number |
UA @ admin @ c:irua:165024 |
Serial |
6283 |
| Permanent link to this record |
| |
|
| |
| Author |
Zarenia, M.; Conti, S.; Peeters, F.M.; Neilson, D. |
| Title |
Coulomb drag in strongly coupled quantum wells : temperature dependence of the many-body correlations |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
115 |
Issue |
20 |
Pages |
202105 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We investigate the effect of the temperature dependence of many-body correlations on hole-hole Coulomb drag in strongly coupled GaAs/GaAlAs double quantum wells. For arbitrary temperatures, we obtained the correlations using the classical-map hypernetted-chain approach. We compare the temperature dependence of the resulting drag resistivities rho D(T) at different densities with rho D(T) calculated assuming correlations fixed at zero temperature. Comparing the results with those when correlations are completely neglected, we confirm that correlations significantly increase the drag. We find that the drag becomes sensitive to the temperature dependence of T greater than or similar to 2TF, twice the Fermi temperature. Our results show excellent agreement with available experimental data. Published under license by AIP Publishing. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000498619400007 |
Publication Date |
2019-11-14 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.411 |
Times cited |
2 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.411 |
| Call Number |
UA @ admin @ c:irua:165135 |
Serial |
6291 |
| Permanent link to this record |
| |
|
| |
| Author |
Xue, C.; He, A.; Milošević, M.V.; Silhanek, A., V; Zhou, Y.-H. |
| Title |
Open circuit voltage generated by dragging superconducting vortices with a dynamic pinning potential |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
| Volume |
21 |
Issue |
11 |
Pages |
113044 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We theoretically investigate, through Ginzburg?Landau simulations, the possibility to induce an open circuit voltage in absence of applied current, by dragging superconducting vortices with a dynamic pinning array as for instance that created by a nearby sliding vortex lattice or moving laser spots. Different dynamic regimes, such as synchronous vortex motion or dynamic vortex chains consisting of laggard vortices, can be observed by varying the velocity of the sliding pinning potential and the applied magnetic field. Additionally, due to the edge barrier, significantly different induced voltage is found depending on whether the vortices are dragged along the superconducting strip or perpendicular to the lateral edges. The output voltage in the proposed mesoscopic superconducting dynamo can be tuned by varying size, density and directions of the sliding pinning potential. |
| 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 |
000498853700001 |
Publication Date |
2019-11-05 |
| 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 |
6 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.786 |
| Call Number |
UA @ admin @ c:irua:165158 |
Serial |
6317 |
| Permanent link to this record |
| |
|
| |
| Author |
Ozcan, M.; Ozen, S.; Yagmurcukardes, M.; Sahin, H. |
| Title |
Structural, electronic and vibrational properties of ultra-thin octahedrally coordinated structure of EuO2 |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Journal Of Magnetism And Magnetic Materials |
Abbreviated Journal |
J Magn Magn Mater |
| Volume |
493 |
Issue |
493 |
Pages |
165668 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Novel stable ultra-thin phases of europium oxide are investigated by means of state-of-the-art first principles calculations. Total energy calculations show that single layers of EuO2 and Eu(OH)(2) can be stabilized in an octahedrally coordinated (1T) atomic structure. However, phonon calculations reveal that although both structures are energetically feasible, only the 1T-EuO2 phase has dynamical stability. The phonon spectrum of 1T-EuO2 displays three Raman active modes; a non-degenerate out-of-plane A(1g) mode at 353.5 cm(-1) and two doubly-degenerate in-plane E-g modes at 304.3 cm(-1). Furthermore, magnetic ground state and electronic band dispersion calculations show that the single layer EuO2 is a metal with net magnetic moment of 5(mu B) per unitcell resulting in a half-metallic ferrimagnetic behavior. Moreover, robustness of the half-metallic ferrimagnetic characteristics of EuO2 is confirmed by the application of electric field and charging. Single layer 1T-EuO2, with its stable ultra-thin structure and half-metallic ferrimagnetic feature, is a promising novel material for nanoscale electronic and spintronic applications. |
| 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 |
000486397800003 |
Publication Date |
2019-08-03 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0304-8853 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.7 |
Times cited |
1 |
Open Access |
|
| Notes |
; Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). HS acknowledges financial support from the TUBITAK under the project number 117F095. MY is supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship. ; |
Approved |
Most recent IF: 2.7; 2020 IF: 2.63 |
| Call Number |
UA @ admin @ c:irua:162755 |
Serial |
6323 |
| Permanent link to this record |
| |
|
| |
| Author |
Bafekry, A.; Shayesteh, S.F.; Ghergherehchi, M.; Peeters, F.M. |
| Title |
Tuning the bandgap and introducing magnetism into monolayer BC3 by strain/defect engineering and adatom/molecule adsorption |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| Volume |
126 |
Issue |
14 |
Pages |
144304 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Using first-principles calculations, we study the structural, electronic, and optical properties of pristine BC3. Our results show that BC3 is a semiconductor which can be useful in optoelectronic device applications. Furthermore, we found that the electronic properties of BC3 can be modified by strain and the type of edge states. With increasing thickness, the indirect bandgap decreases from 0.7 eV (monolayer) to 0.27 eV (bulk). Upon uniaxial tensile strain along the armchair and zigzag directions, the bandgap slightly decreases, and with increasing uniaxial strain, the bandgap decreases, and when reaching -8%, a semiconductor-to-metal transition occurs. By contrast, under biaxial strain, the bandgap increases to 1.2 eV in +8% and decreases to zero in -8%. BC3 nanoribbons with different widths exhibit magnetism at the zigzag edges, while, at the armchair edges, they become semiconductor, and the bandgap is in the range of 1.0-1.2 eV. Moreover, we systematically investigated the effects of adatoms/molecule adsorption and defects on the structural, electronic, and magnetic properties of BC3. The adsorption of various adatoms and molecules as well as topological defects (vacancies and Stone-Wales defects) can modify the electronic properties. Using these methods, one can tune BC3 into a metal, half-metal, ferromagnetic-metal, and dilute-magnetic semiconductor or preserve its semiconducting character. Published under license by AIP Publishing. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Wos |
000503995300019 |
Publication Date |
2019-10-10 |
| 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 |
2.068 |
Times cited |
56 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.068 |
| Call Number |
UA @ admin @ c:irua:165160 |
Serial |
6328 |
| Permanent link to this record |
| |
|
| |
| Author |
Bafekry, A.; Shayesteh, S.F.; Peeters, F.M. |
| Title |
Two-dimensional carbon nitride (2DCN) nanosheets : tuning of novel electronic and magnetic properties by hydrogenation, atom substitution and defect engineering |
Type |
A1 Journal article |
| Year |
2019 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| Volume |
126 |
Issue |
21 |
Pages |
215104 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
By employing first-principles calculations within the framework of density functional theory, we investigated the structural, electronic, and magnetic properties of graphene and various two-dimensional carbon-nitride (2DNC) nanosheets. The different 2DCN gives rise to diverse electronic properties such as metals (C3N2), semimetals (C4N and C9N4), half-metals (C4N3), ferromagnetic-metals (C9N7), semiconductors (C2N, C3N, C3N4, C6N6, and C6N8), spin-glass semiconductors (C10N9 and C14N12), and insulators (C2N2). Furthermore, the effects of adsorption and substitution of hydrogen atoms as well as N-vacancy defects on the electronic and magnetic properties are systematically studied. The introduction of point defects, including N vacancies, interstitial H impurity into graphene and different 2DCN crystals, results in very different band structures. Defect engineering leads to the discovery of potentially exotic properties that make 2DCN interesting for future investigations and emerging technological applications with precisely tailored properties. These properties can be useful for applications in various fields such as catalysis, energy storage, nanoelectronic devices, spintronics, optoelectronics, and nanosensors. Published under license by AIP Publishing. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Wos |
000504007300023 |
Publication Date |
2019-12-02 |
| 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 |
2.068 |
Times cited |
70 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.068 |
| Call Number |
UA @ admin @ c:irua:165733 |
Serial |
6329 |
| Permanent link to this record |
| |
|
| |
| Author |
Gonzalez-Garcia, A.; Lopez-Perez, W.; Gonzalez-Hernandez, R.; Rivera-Julio, J.; Espejo, C.; Milošević, M.V.; Peeters, F.M. |
| Title |
Two-dimensional hydrogenated buckled gallium arsenide: an ab initio study |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Journal Of Physics-Condensed Matter |
Abbreviated Journal |
J Phys-Condens Mat |
| Volume |
32 |
Issue |
14 |
Pages |
145502 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
First-principles calculations have been carried out to investigate the stability, structural and electronic properties of two-dimensional (2D) hydrogenated GaAs with three possible geometries: chair, zigzag-line and boat configurations. The effect of van der Waals interactions on 2D H-GaAs systems has also been studied. These configurations were found to be energetic and dynamic stable, as well as having a semiconducting character. Although 2D GaAs adsorbed with H tends to form a zigzag-line configuration, the energy differences between chair, zigzag-line and boat are very small which implies the metastability of the system. Chair and boat configurations display a – direct bandgap nature, while pristine 2D-GaAs and zigzag-line are indirect semiconductors. The bandgap sizes of all configurations are also hydrogen dependent, and wider than that of pristine 2D-GaAs with both PBE and HSE functionals. Even though DFT-vdW interactions increase the adsorption energies and reduce the equilibrium distances of H-GaAs systems, it presents, qualitatively, the same physical results on the stability and electronic properties of our studied systems with PBE functional. According to our results, 2D buckled gallium arsenide is a good candidate to be synthesized by hydrogen surface passivation as its group III-V partners 2D buckled gallium nitride and boron nitride. The hydrogenation of 2D-GaAs tunes the bandgap of pristine 2D-GaAs, which makes it a potential candidate for optoelectronic applications in the blue and violet ranges of the visible electromagnetic spectrum. |
| 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 |
000507894400001 |
Publication Date |
2019-12-11 |
| 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 |
| Impact Factor |
2.7 |
Times cited |
2 |
Open Access |
|
| Notes |
; This work has been carried out by the financial support of Universidad del Norte and Colciencias (Administrative Department of Science, Technology and Research of Colombia) under Convocatoria 712-Convocatoria para proyectos de investigacion en Ciencias Basicas, ano 2015, Cod: 121571250192, Contrato 110-216. The authors gratefully acknowledge the support from the High Performance Computing core facility CalcUA and the TOPBOF project at the University of Antwerp, Belgium; and the computing time granted on the supercomputer Mogon at Johannes Gutenberg University Mainz (hpc.uni-mainz.de). ; |
Approved |
Most recent IF: 2.7; 2020 IF: 2.649 |
| Call Number |
UA @ admin @ c:irua:165644 |
Serial |
6330 |
| Permanent link to this record |
| |
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| |
| Author |
Vanherck, J.; Bacaksiz, C.; Sorée, B.; Milošević, M.V.; Magnus, W. |
| Title |
2D ferromagnetism at finite temperatures under quantum scrutiny |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Applied Physics Letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
117 |
Issue |
5 |
Pages |
052401 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| 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. |
| 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 |
000559330100001 |
Publication Date |
2020-08-03 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
4 |
Times cited |
8 |
Open Access |
|
| 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 |
| Call Number |
UA @ admin @ c:irua:171176 |
Serial |
6445 |
| Permanent link to this record |
| |
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| |
| Author |
Sabani, D.; Bacaksiz, C.; Milošević, M.V. |
| Title |
Ab initio methodology for magnetic exchange parameters: Generic four-state energy mapping onto a Heisenberg spin Hamiltonian |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
102 |
Issue |
1 |
Pages |
014457-14458 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| 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. |
| 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 |
000554409500002 |
Publication Date |
2020-07-31 |
| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.7 |
Times cited |
13 |
Open Access |
|
| 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 |
| Call Number |
UA @ admin @ c:irua:171203 |
Serial |
6448 |
| Permanent link to this record |
| |
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| |
| Author |
Topalovic, D.B.; Arsoski, V.V.; Tadic, M.Z.; Peeters, F.M. |
| Title |
Asymmetric versus symmetric HgTe/CdxHg1-x Te double quantum wells: Bandgap tuning without electric field |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Journal Of Applied Physics |
Abbreviated Journal |
J Appl Phys |
| Volume |
128 |
Issue |
6 |
Pages |
064301-64308 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We investigate the electron states in double asymmetric HgTe / Cd x Hg 1 – x Te quantum wells grown along the [ 001 ] direction. The subbands are computed by means of the envelope function approximation applied to the eight-band Kane k . mml:mspace width=“.1em”mml:mspace p model. The asymmetry of the confining potential of the double quantum wells results in a gap opening, which is absent in the symmetric system where it can only be induced by an applied electric field. The bandgap and the subbands are affected by spin-orbit coupling, which is a consequence of the asymmetry of the confining potential. The electron-like and hole-like states are mainly confined in different quantum wells, and the enhanced hybridization between them opens a spin-dependent hybridization gap at a finite in-plane wavevector. We show that both the ratio of the widths of the two quantum wells and the mole fraction of the C d x H g 1 – x Te barrier control both the energy gap between the hole-like states and the hybridization gap. The energy subbands are shown to exhibit inverted ordering, and therefore, a nontrivial topological phase could emerge in the system. |
| 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 |
000561339300001 |
Publication Date |
2020-08-10 |
| 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 |
4 |
Open Access |
|
| Notes |
; This research was funded by the Ministry of Education, Science and Technological Development of the Republic of Serbia and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 3.2; 2020 IF: 2.068 |
| Call Number |
UA @ admin @ c:irua:171146 |
Serial |
6453 |
| Permanent link to this record |
| |
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| |
| Author |
McNaughton, B.; Milošević, M.V.; Perali, A.; Pilati, S. |
| 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 |
| Volume |
101 |
Issue |
5 |
Pages |
053312 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| 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. |
| 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 |
000535862000014 |
Publication Date |
2020-05-28 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1539-3755; 1550-2376 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.366 |
Times cited |
15 |
Open Access |
|
| 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 |
| Call Number |
UA @ admin @ c:irua:170244 |
Serial |
6463 |
| Permanent link to this record |
| |
|
| |
| Author |
Mirzakhani, M.; Peeters, F.M.; Zarenia, M. |
| Title |
Circular quantum dots in twisted bilayer graphene |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
101 |
Issue |
7 |
Pages |
075413 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Within a tight-binding approach, we investigate the effect of twisting angle on the energy levels of circular bilayer graphene (BLG) quantum dots (QDs) in both the absence and presence of a perpendicular magnetic field. The QDs are defined by an infinite-mass potential, so that the specific edge effects are not present. In the absence of magnetic field (or when the magnetic length is larger than the moire length), we show that the low-energy states in twisted BLG QDs are completely affected by the formation of moire patterns, with a strong localization at AA-stacked regions. When magnetic field increases, the energy gap of an untwisted BLG QD closes with the edge states, localized at the boundaries between the AA- and AB-stacked spots in a twisted BLG QD. Our observation of the spatial localization of the electrons in twisted BLG QDs can be experimentally probed by low-bias scanning tunneling microscopy measurements. |
| 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 |
000512772200004 |
Publication Date |
2020-02-13 |
| 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 |
19 |
Open Access |
|
| Notes |
; We gratefully acknowledge discussions with I. Snyman. M.Z. acknowledges support from the U.S. Department of Energy (Office of Science) under Grant No. DE-FG0205ER46203. ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:166493 |
Serial |
6470 |
| Permanent link to this record |
| |
|
| |
| Author |
Bafekry, A.; Stampfl, C.; Akgenc, B.; Ghergherehchi, M. |
| Title |
Control of C3N4 and C4N3 carbon nitride nanosheets' electronic and magnetic properties through embedded atoms |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Physical Chemistry Chemical Physics |
Abbreviated Journal |
Phys Chem Chem Phys |
| Volume |
22 |
Issue |
4 |
Pages |
2249-2261 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
In the present work, the effect of various embedded atom impurities on tuning electronic and magnetic properties of C3N4 and C4N3 nanosheets have been studied using first-principles calculations. Our calculations show that C3N4 is a semiconductor and it exhibits extraordinary electronic properties such as dilute-magnetic semiconductor (with H, F, Cl, Be, V, Fe and Co); metal (with N, P, Mg and Ca), half-metal (with Li, Na, K, Al, Sc, Cr, Mn, and Cu) and semiconductor (with O, S, B, C, Si, Ti, Ni and Zn) with the band gaps in the range of 0.3-2.0 eV depending on the species of embedded atom. The calculated electronic properties reveal that C4N3 is a half-metal and it retains half-metallic character with embedded H, O, S, F, B, N, P, Be, Mg, Al, Sc, V, Fe, Ni and Zn atoms. The substitution of Cl, C, Cr and Mn atoms create ferromagnetic-metal character in the C4N3 nanosheet, embedded Co and Cu atoms exhibit a dilute-magnetic semiconductor nature, and embedded Ti atoms result in the system becoming a semiconductor. Therefore, our results reveal the fact that the band gap and magnetism can be modified or induced by various atom impurities, thus, offering effective possibilities to tune the electronic and magnetic properties of C3N4 and C4N3 nanosheets. |
| Address |
|
| Corporate Author |
|
Thesis |
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| Publisher |
|
Place of Publication |
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Editor |
|
| Language |
|
Wos |
000510729400042 |
Publication Date |
2019-12-24 |
| 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 |
3.3 |
Times cited |
18 |
Open Access |
|
| Notes |
; This work has supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). B. Akgenc acknowledges financial support the Kirklareli University-BAP under the Project No 189 and TUBITAK ULAKBIM, High Performance and Grid Computing Center. ; |
Approved |
Most recent IF: 3.3; 2020 IF: 4.123 |
| Call Number |
UA @ admin @ c:irua:166553 |
Serial |
6476 |
| Permanent link to this record |
| |
|
| |
| Author |
Vargas Paredes, A.A.; Shanenko, A.A.; Vagov, A.; Milošević, M.V.; Perali, A. |
| Title |
Crossband versus intraband pairing in superconductors: signatures and consequences of the interplay |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
101 |
Issue |
9 |
Pages |
094516-94517 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We analyze the paradigmatic competition between intraband and crossband Cooper-pair formation in twoband superconductors, neglected in most works to date. We derive the phase-sensitive gap equations and describe the crossover between the intraband-dominated and the crossband-dominated regimes, delimited by a “gapless” state. Experimental signatures of crosspairing comprise notable gap splitting in the excitation spectrum, non-BCS behavior of gaps versus temperature, as well as changes in the pairing symmetry as a function of temperature. The consequences of these findings are illustrated on the examples of MgB2 and Ba0.6K0.4Fe2As2. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000522074900002 |
Publication Date |
2020-03-27 |
| 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 |
14 |
Open Access |
|
| Notes |
; This collaborative work was fostered within the international Multi Super network on Multi-condensate Superconductivity and Superfluidity [70]. The authors thank Andrea Guidini for his help during the initial stage of this work and Laura Fanfarillo for useful discussions. This work was partially supported by the Italian MIUR through the PRIN 2015 program (Contract No. 2015C5SEJJ001) and the Research Foundation -Flanders (FWO). A.A.V.-P. acknowledges support by the joint doctoral program and by the Erasmus+ exchange between the University of Antwerp and the University of Camerino. M.V.M. gratefully acknowledges support from a Visiting Professorship at the University of Camerino. A.S. and A.V. acknowledge support from the CAPES/Print Grant, Process No. 88887.333666/ 2019-00 (Brazil) and the Russian Science Foundation Project No. 18-12-00429, respectively. ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:168605 |
Serial |
6479 |
| Permanent link to this record |
| |
|
| |
| Author |
Conti, S.; Van der Donck, M.; Perali, A.; Peeters, F.M.; Neilson, D. |
| Title |
Doping-dependent switch from one- to two-component superfluidity in coupled electron-hole van der Waals heterostructures |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
| Volume |
101 |
Issue |
22 |
Pages |
220504-220506 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The hunt for high-temperature superfluidity has received new impetus from the discovery of atomically thin stable materials. Electron-hole superfluidity in coupled MoSe2-WSe2 monolayers is investigated using a mean-field multiband model that includes band splitting caused by strong spin-orbit coupling. This splitting leads to a large energy misalignment of the electron and hole bands which is strongly modified by interchanging the doping of the monolayers. The choice of doping determines if the superfluidity is tunable from one to two components. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
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Editor |
|
| Language |
|
Wos |
000538941900002 |
Publication Date |
2020-06-09 |
| 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 |
12 |
Open Access |
|
| Notes |
; This work was partially supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl), the Methusalem Foundation, and the FLAG-ERA project TRANS2DTMD. We thank A. R. Hamilton and A. Vargas-Paredes for useful discussions. ; |
Approved |
Most recent IF: 3.7; 2020 IF: 3.836 |
| Call Number |
UA @ admin @ c:irua:170201 |
Serial |
6489 |
| Permanent link to this record |
| |
|
| |
| Author |
Bafekry, A.; Yagmurcukardes, M.; Shahrokhi, M.; Ghergherehchi, M. |
| Title |
Electro-optical properties of monolayer and bilayer boron-doped C₃N: Tunable electronic structure via strain engineering and electric field |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Carbon |
Abbreviated Journal |
Carbon |
| Volume |
168 |
Issue |
|
Pages |
220-229 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| 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. |
| 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 |
000565900900008 |
Publication Date |
2020-07-13 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0008-6223 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
10.9 |
Times cited |
21 |
Open Access |
|
| 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 |
| Call Number |
UA @ admin @ c:irua:171914 |
Serial |
6500 |
| Permanent link to this record |
| |
|
| |
| Author |
Bafekry, A.; Stampfl, C.; Peeters, F.M. |
| 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 |
| Year |
2020 |
Publication |
Physica Status Solidi B-Basic Solid State Physics |
Abbreviated Journal |
Phys Status Solidi B |
| Volume |
|
Issue |
|
Pages |
2000182-12 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| 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. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
|
Place of Publication |
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Editor |
|
| Language |
|
Wos |
000527679200001 |
Publication Date |
2020-04-23 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0370-1972 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.6 |
Times cited |
40 |
Open Access |
|
| 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 |
| Call Number |
UA @ admin @ c:irua:168730 |
Serial |
6502 |
| Permanent link to this record |
| |
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| |
| Author |
Kenawy, A.; Magnus, W.; Milošević, M.V.; Sorée, B. |
| Title |
Electronically tunable quantum phase slips in voltage-biased superconducting rings as a base for phase-slip flux qubits |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Superconductor Science & Technology |
Abbreviated Journal |
Supercond Sci Tech |
| Volume |
33 |
Issue |
12 |
Pages |
125002 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Quantum phase slips represent a coherent mechanism to couple flux states of a superconducting loop. Since their first direct observation, there have been substantial developments in building charge-insensitive quantum phase-slip circuits. At the heart of these devices is a weak link, often a nanowire, interrupting a superconducting loop. Owing to the very small cross-sectional area of such a nanowire, quantum phase slip rates in the gigahertz range can be achieved. Instead, here we present the use of a bias voltage across a superconducting loop to electrostatically induce a weak link, thereby amplifying the rate of quantum phase slips without physically interrupting the loop. Our simulations reveal that the bias voltage modulates the free energy barrier between subsequent flux states in a very controllable fashion, providing a route towards a phase-slip flux qubit with a broadly tunable transition frequency. |
| 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 |
000577207000001 |
Publication Date |
2020-09-16 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0953-2048 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.6 |
Times cited |
4 |
Open Access |
|
| Notes |
; ; |
Approved |
Most recent IF: 3.6; 2020 IF: 2.878 |
| Call Number |
UA @ admin @ c:irua:172643 |
Serial |
6503 |
| Permanent link to this record |
| |
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| |
| Author |
Bafekry, A.; Stampfl, C.; Akgenc, B.; Mortazavi, B.; Ghergherehchi, M.; Nguyen, C.V. |
| Title |
Embedding of atoms into the nanopore sites of the C₆N₆ and C₆N₈ porous carbon nitride monolayers with tunable electronic properties |
Type |
A1 Journal article |
| Year |
2020 |
Publication |
Physical Chemistry Chemical Physics |
Abbreviated Journal |
Phys Chem Chem Phys |
| Volume |
22 |
Issue |
11 |
Pages |
6418-6433 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Using first-principles calculations, we study the effect of embedding various atoms into the nanopore sites of both C6N6 and C6N8 monolayers. Our results indicate that the embedded atoms significantly affect the electronic and magnetic properties of C6N6 and C6N8 monolayers and lead to extraordinary and multifarious electronic properties, such as metallic, half-metallic, spin-glass semiconductor and dilute-magnetic semiconductor behaviour. Our results reveal that the H atom concentration dramatically affects the C6N6 monolayer. On increasing the H coverage, the impurity states also increase due to H atoms around the Fermi-level. C6N6 shows metallic character when the H atom concentration reaches 6.25%. Moreover, the effect of charge on the electronic properties of both Cr@C6N6 and C@C6N8 is also studied. Cr@C6N6 is a ferromagnetic metal with a magnetic moment of 2.40 mu(B), and when 0.2 electrons are added and removed, it remains a ferromagnetic metal with a magnetic moment of 2.57 and 2.77 mu(B), respectively. Interestingly, one can observe a semi-metal, in which the VBM and CBM in both spin channels touch each other near the Fermi-level. C@C6N8 is a semiconductor with a nontrivial band gap. When 0.2 electrons are removed, it remains metallic, and under excess electronic charge, it exhibits half-metallic behaviour. |
| 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 |
000523409400037 |
Publication Date |
2020-02-20 |
| 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 |
3.3 |
Times cited |
17 |
Open Access |
|
| Notes |
; This work was supported by a National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (NRF-2017R1A2B2011989). ; |
Approved |
Most recent IF: 3.3; 2020 IF: 4.123 |
| Call Number |
UA @ admin @ c:irua:168617 |
Serial |
6504 |
| Permanent link to this record |
