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Records |
Links |
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Author |
Milovanović, S.P.; Andelkovic, M.; Covaci, L.; Peeters, F.M. |
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Title |
Band flattening in buckled monolayer graphene |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
102 |
Issue |
24 |
Pages |
245427 |
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| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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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. |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000602844600007 |
Publication Date |
2020-12-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor  |
3.7 |
Times cited |
27 |
Open Access |
OpenAccess |
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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 |
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Call Number |
UA @ admin @ c:irua:175021 |
Serial |
6684 |
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| Permanent link to this record |
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Author |
Wang, J.; Van Pottelberge, R.; Zhao, W.-S.; Peeters, F.M. |
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Title |
Coulomb impurity on a Dice lattice : atomic collapse and bound states |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
105 |
Issue |
3 |
Pages |
035427 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The modification of the quantum states in a Dice lattice due to a Coulomb impurity are investigated. The energy-band structure of a pristine Dice lattice consists of a Dirac cone and a flat band at the Dirac point. We use the tight-binding formalism and find that the flat band states transform into a set of discrete bound states whose electron density is localized on a ring around the impurity mainly on two of the three sublattices. Its energy is proportional to the strength of the Coulomb impurity. Beyond a critical strength of the Coulomb potential atomic collapse states appear that have some similarity with those found in graphene with the difference that the flat band states contribute with an additional ringlike electron density that is spatially decoupled from the atomic collapse part. At large value of the strength of the Coulomb impurity the flat band bound states anticross with the atomic collapse states. |
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Place of Publication |
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Editor |
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Wos |
000749375200002 |
Publication Date |
2022-01-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.7 |
Times cited |
3 |
Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 3.7 |
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Call Number |
UA @ admin @ c:irua:186387 |
Serial |
6977 |
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Author |
Yu, Y.; Chen, X.; Liu, X.; Li, J.; Sanyal, B.; Kong, X.; Peeters, F.M.; Li, L. |
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Title |
Ferromagnetism with in-plane magnetization, Dirac spin-gapless semiconducting properties, and tunable topological states in two-dimensional rare-earth metal dinitrides |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
105 |
Issue |
2 |
Pages |
024407 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Since the successful synthesis of bulk single crystals MoN2 and ReN2, which have a layered structure, transition-metal dinitrides have attracted considerable attention in recent years. Here, we focus on rare-earth metal (Rem) elements, and propose seven stable Rem dinitride monolayers with a 1T structure, namely, 1T-RemN2. We use first-principles calculations, and find that these monolayers have a ferromagnetic ground state with in-plane magnetization. Without spin-orbit coupling (SOC), the band structures are spin-polarized with Dirac points at the Fermi level. Remarkably, the 1T-LuN2 monolayer exhibits an isotropic magnetocrystalline anisotropy energy in the xy plane with in-plane magnetization, indicating easy tunability of the magnetization direction. When rotating the magnetization vector in the xy plane, we propose a model that accurately describes the variation of the SOC band gap and the two possible topological states (Weyl-like semimetal and Chern insulator states) whose properties are tunable. The Weyl-like semimetal state is a critical point between the two Chern insulator states with opposite sign of the Chern numbers (+/- 1). The nontrivial band gap (up to 60.3 meV) and the Weyl-like semimetal state are promising for applications in spintronic devices. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000742384700001 |
Publication Date |
2022-01-06 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.7 |
Times cited |
13 |
Open Access |
Not_Open_Access: Available from 06.07.2202 |
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Notes |
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Approved |
Most recent IF: 3.7 |
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Call Number |
UA @ admin @ c:irua:186514 |
Serial |
6991 |
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Author |
Zhang, H.Y.; Xiao, Y.M.; N. Li, Q.; Ding, L.; Van Duppen, B.; Xu, W.; Peeters, F.M. |
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Title |
Anisotropic and tunable optical conductivity of a two-dimensional semi-Dirac system in the presence of elliptically polarized radiation |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
105 |
Issue |
11 |
Pages |
115423-115429 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We investigate the effect of ellipticity ratio of the polarized radiation field on optoelectronic properties of a two-dimensional (2D) semi-Dirac (SD) system. The optical conductivity is calculated within the energy balance equation approach derived from the semiclassical Boltzmann equation. We find that there exists the anisotropic optical absorption induced via both the intra-and interband electronic transition channels in the perpendicular xx and yy directions. Furthermore, we examine the effects of the ellipticity ratio, the temperature, the carrier density, and the band-gap parameter on the optical conductivity of the 2D SD system placed in transverse and vertical directions, respectively. It is shown that the ellipticity ratio, temperature, carrier density, and band-gap parameter can play the important roles in tuning the strength, peak position, and shape of the optical conductivity spectrum. The results obtained from this study indicate that the 2D SD system can be a promising anisotropic and tunable optical and optoelectronic material for applications in innovative 2D optical and optoelectronic devices, which are active in the infrared and terahertz bandwidths. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Language |
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Wos |
000802810700002 |
Publication Date |
2022-03-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.7 |
Times cited |
3 |
Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 3.7 |
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Call Number |
UA @ admin @ c:irua:188660 |
Serial |
7125 |
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| Permanent link to this record |
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Author |
Shafiei, M.; Fazileh, F.; Peeters, F.M.; Milošević, M.V. |
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Title |
Controlling the hybridization gap and transport in a thin-film topological insulator : effect of strain, and electric and magnetic field |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
106 |
Issue |
3 |
Pages |
035119-7 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
In a thin-film topological insulator (TI), the edge states on two surfaces may couple by quantum tunneling, opening a gap known as the hybridization gap. Controlling the hybridization gap and transport has a variety of potential uses in photodetection and energy-harvesting applications. In this paper, we report the effect of strain, and electric and magnetic field, on the hybridization gap and transport in a thin Bi2Se3 film, investigated within the tight-binding theoretical framework. We demonstrate that vertical compression decreases the hybridization gap, as does tensile in-plane strain. Applying an electric field breaks the inversion symmetry and leads to a Rashba-like spin splitting proportional to the electric field, hence closing and reopening the gap. The influence of a magnetic field on thin-film TI is also discussed, starting from the role of an out-of-plane magnetic field on quantum Hall states. We further demonstrate that the hybridization gap can be controlled by an in-plane magnetic field, and that by applying a sufficiently strong field a quantum phase transition from an insulator to a semimetal can be achieved. |
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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 |
000832277500001 |
Publication Date |
2022-07-13 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.7 |
Times cited |
7 |
Open Access |
Not_Open_Access |
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Notes |
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Approved |
Most recent IF: 3.7 |
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Call Number |
UA @ admin @ c:irua:189515 |
Serial |
7140 |
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Author |
Mirzakhani, M.; da Costa, D.R.; Peeters, F.M. |
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Title |
Isolated and hybrid bilayer graphene quantum rings |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
105 |
Issue |
11 |
Pages |
115430-11 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Using the continuum model, we investigate the electronic properties of two types of bilayer graphene (BLG) quantum ring (QR) geometries: (i) An isolated BLG QR and (ii) a monolayer graphene (MLG) with a QR put on top of an infinite graphene sheet (hybrid BLG QR). Solving the Dirac-Weyl equation in the presence of a perpendicular magnetic field and applying the infinite mass boundary condition at the ring boundaries, we obtain analytical results for the energy levels and corresponding wave spinors for both structures. In the case of isolated BLG QR, we observe a sizable and magnetically tunable band gap which agrees with the tight-binding transport simulations. Our analytical results also show the intervalley symmetry EeK (m) = ???EK??? h (m) between the electron (e) and the hole (h) states (m is the angular momentum quantum number) for the energy spectrum of the isolated BLG QR. The presence of interface boundary in a hybrid BLG QR modifies drastically the energy levels as compared with that of an isolated BLG QR. Its energy levels are tunable from MLG dot to isolated BLG QR and to MLG Landau energy levels as the magnetic field is varied. Our predictions can be verified experimentally using different techniques such as by magnetotransport measurements. |
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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 |
000801209300006 |
Publication Date |
2022-03-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.7 |
Times cited |
4 |
Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 3.7 |
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Call Number |
UA @ admin @ c:irua:188703 |
Serial |
7175 |
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Author |
Cunha, S.M.; da Costa, D.R.; Pereira, J.M., Jr.; Costa Filho, R.N.; Van Duppen, B.; Peeters, F.M. |
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Title |
Tunneling properties in α-T₃ lattices : effects of symmetry-breaking terms |
Type |
A1 Journal article |
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Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
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| |
Volume |
105 |
Issue |
16 |
Pages |
165402-165414 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The alpha-T3 lattice model interpolates a honeycomb (graphene-like) lattice and a T3 (also known as dice) lattice via the parameter alpha. These lattices are made up of three atoms per unit cell. This gives rise to an additional dispersionless flat band touching the conduction and valence bands. Electrons in this model are analogous to Dirac fermions with an enlarged pseudospin, which provides unusual tunneling features like omnidirectional Klein tunneling, also called super-Klein tunneling (SKT). However, it is unknown how small deviations in the equivalence between the atomic sites, i.e., variations in the alpha parameter, and the number of tunnel barriers changes the transmission properties. Moreover, it is interesting to learn how tunneling occurs through regions where the energy spectrum changes from linear with a middle flat band to a hyperbolic dispersion. In this paper we investigate these properties, its dependence on the number of square barriers and the alpha parameter for either gapped and gapless cases. Furthermore, we compare these results to the case where electrons tunnel from a region with linear dispersion to a region with a bandgap. In the latter case, contrary to tunneling through a potential barrier, the SKT is no longer observed. Finally, we find specific cases where transmission is allowed due to a symmetry breaking of sublattice equivalence. |
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Corporate Author |
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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 |
000805195200001 |
Publication Date |
2022-04-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.7 |
Times cited |
|
Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 3.7 |
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Call Number |
UA @ admin @ c:irua:188614 |
Serial |
7222 |
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| Permanent link to this record |
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Author |
Shafiei, M.; Fazileh, F.; Peeters, F.M.; Milošević, M.V. |
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Title |
High Chern number in strained thin films of dilute magnetic topological insulators |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Physical review B |
Abbreviated Journal |
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| |
Volume |
107 |
Issue |
19 |
Pages |
195119-6 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The quantum anomalous Hall effect was first observed experimentally by doping the Bi2Se3 materials family with chromium, where 5% doping induces an exchange field of around 0.1 eV. In ultrathin films, a topological phase transition from a normal insulator to a Chern insulator can be induced with an exchange field proportional to the hybridization gap. Subsequent transitions to states with higher Chern numbers require an exchange field larger than the (bulk) band gap, but are prohibited in practice by the detrimental effects of higher doping levels. Here, we show that threshold doping for these phase transitions in thin films is controllable by strain. As a consequence, higher Chern states can be reached with experimentally feasible doping, sufficiently dilute for the topological insulator to remain structurally stable. Such a facilitated realization of higher Chern insulators opens prospects for multichannel quantum computing, higher-capacity circuit interconnects, and energy-efficient electronic devices at elevated temperatures. |
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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 |
000995111000003 |
Publication Date |
2023-05-11 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.7 |
Times cited |
2 |
Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 3.7; 2023 IF: 3.836 |
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Call Number |
UA @ admin @ c:irua:197295 |
Serial |
8820 |
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Author |
Ahmadkhani, S.; Alihosseini, M.; Ghasemi, S.; Ahmadabadi, I.; Hassani, N.; Peeters, F.M.; Neek-Amal, M. |
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Title |
Multiband flattening and linear Dirac band structure in graphene with impurities |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Physical review B |
Abbreviated Journal |
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Volume |
107 |
Issue |
7 |
Pages |
075401-75408 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Flat bands in the energy spectrum have attracted a lot of attention in recent years because of their unique properties and promising applications. Special arrangement of impurities on monolayer graphene are proposed to generate multiflat bands in the electronic band structure. In addition to the single midgap states in the spectrum of graphene with low hydrogen density, we found closely spaced bands around the Fermi level with increasing impurity density, which are similar to discrete lines in the spectrum of quantum dots, as well as the unusual Landau-level energy spectrum of graphene in the presence of a strong magnetic field. The presence of flat bands crucially depends on whether or not there are odd or even electrons of H(F) atoms bound to graphene. Interestingly, we found that a fully hydrogenated (fluoridated) of a hexagon of graphene sheet with six hydrogen (fluorine) atoms sitting on top and bottom in consecutive order exhibits Dirac cones in the electronic band structure with a 20% smaller Fermi velocity as compared to the pristine graphene. Functionalizing graphene introduces various C-C bond lengths resulting in nonuniform strains. Such a nonuniform strain may induce a giant pseudomagnetic field in the system, resulting in quantum Hall effect. |
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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 |
000994364500006 |
Publication Date |
2023-02-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.7 |
Times cited |
1 |
Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 3.7; 2023 IF: 3.836 |
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Call Number |
UA @ admin @ c:irua:197431 |
Serial |
8822 |
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| Permanent link to this record |
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Author |
Lima, I.L.C.; Milošević, M.V.; Peeters, F.M.; Chaves, A. |
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Title |
Tuning of exciton type by environmental screening |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Physical review B |
Abbreviated Journal |
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Volume |
108 |
Issue |
11 |
Pages |
115303-115308 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We theoretically investigate the binding energy and electron-hole (e-h) overlap of excitonic states confined at the interface between two-dimensional materials with type-II band alignment, i.e., with lowest conduction and highest valence band edges placed in different materials, arranged in a side-by-side planar heterostructure. We propose a variational procedure within the effective mass approximation to calculate the exciton ground state and apply our model to a monolayer MoS2/WS2 heterostructure. The role of nonabrupt interfaces between the materials is accounted for in our model by assuming a WxMo1-xS2 alloy around the interfacial region. Our results demonstrate that (i) interface-bound excitons are energetically favorable only for small interface thickness and/or for systems under high dielectric screening by the materials surrounding the monolayer, and that (ii) the interface exciton binding energy and its e-h overlap are controllable by the interface width and dielectric environment. |
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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 |
001077758300002 |
Publication Date |
2023-09-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.7 |
Times cited |
1 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.7; 2023 IF: 3.836 |
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Call Number |
UA @ admin @ c:irua:200356 |
Serial |
9110 |
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| Permanent link to this record |
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Author |
Wang, J.; Zhao, W.-S.; Hu, Y.; Filho, R.N.C.; Peeters, F.M. |
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Title |
Charged vacancy in graphene : interplay between Landau levels and atomic collapse resonances |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Physical review B |
Abbreviated Journal |
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Volume |
109 |
Issue |
10 |
Pages |
104103-104106 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The interplay between a magnetic field and the Coulomb potential from a charged vacancy on the electron states in graphene is investigated within the tight-binding model. The Coulomb potential removes locally Landau level degeneracy, while the vacancy introduces a satellite level next to the normal Landau level. These satellite levels are found throughout the positive-energy region, but in the negative-energy region, they turn into atomic collapse resonances. Crossings between Landau levels with different angular quantum number m are found. Unlike the point impurity system in which an anticrossing occurs between Landau levels of the same m, in this work anticrossing is found between the normal Landau level and the vacancy-induced level. The atomic collapse resonance hybridizes with the Landau levels. The charge at which the lowest Landau level m = -1, N = 1 crosses E = 0 increases with enhancing magnetic field. A Landau level scaling anomaly occurs when the charge is larger than the critical charge beta 0.6 and this critical charge is independent of the magnetic field. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
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Editor |
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| |
Language |
|
Wos |
001199561900008 |
Publication Date |
2024-03-04 |
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| |
Series Editor |
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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 |
|
| |
Impact Factor |
3.7 |
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.7; 2024 IF: 3.836 |
|
| |
Call Number |
UA @ admin @ c:irua:205508 |
Serial |
9137 |
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| Permanent link to this record |
| |
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| |
|
Author |
Moura, V.N.; Chaves, A.; Peeters, F.M.; Milošević, M.V. |
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| |
Title |
McMillan-Ginzburg-Landau theory of singularities and discommensurations in charge density wave states of transition metal dichalcogenides |
Type |
A1 Journal article |
| |
Year |
2024 |
Publication |
Physical review B |
Abbreviated Journal |
|
|
| |
Volume |
109 |
Issue |
9 |
Pages |
094507-94511 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The McMillan-Ginzburg-Landau (MGL) model for charge density waves (CDW) is employed in a systematic phenomenological study of the different phases that have been probed in recent experiments involving transition metal dichalcogenides. We implemented an efficient imaginary time evolution method to solve the MGL equations, which enabled us to investigate the role of different coupling parameters on the CDW patterns and to perform calculations with different energy functionals that lead to several experimentally observed singularities in the CDW phase profiles. In particular, by choosing the appropriate energy functionals, we were able to obtain phases that go beyond the well-known periodic phase slips (discommensurations), exhibiting also topological defects (i.e., vortex-antivortex pairs), domain walls where the CDW order parameter is suppressed, and even CDW with broken rotational symmetry. Finally, we briefly discuss the effect of these different CDW phases on the profile and critical temperature of the competing superconducting state. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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| |
Language |
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Wos |
001199651500001 |
Publication Date |
2024-03-11 |
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| |
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 |
|
| |
Impact Factor |
3.7 |
Times cited |
|
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.7; 2024 IF: 3.836 |
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| |
Call Number |
UA @ admin @ c:irua:205491 |
Serial |
9158 |
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| Permanent link to this record |
| |
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| |
|
Author |
Shafiei, M.; Fazileh, F.; Peeters, F.M.; Milošević, M.V. |
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| |
Title |
Tailoring weak and metallic phases in a strong topological insulator by strain and disorder : conductance fluctuations signatures |
Type |
A1 Journal article |
| |
Year |
2024 |
Publication |
Physical review B |
Abbreviated Journal |
|
|
| |
Volume |
109 |
Issue |
4 |
Pages |
045129-7 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Transport measurements are readily used to probe different phases in disordered topological insulators (TIs), where determining topological invariants explicitly is challenging. On that note, universal conductance fluctuations (UCF) theory asserts the conductance G for an ensemble has a Gaussian distribution, and that standard deviation 8G depends solely on the symmetries and dimensions of the system. Using a real-space tight -binding Hamiltonian on a system with Anderson disorder, we explore conductance fluctuations in a thin Bi2Se3 film and demonstrate the agreement of their behavior with UCF hypotheses. We further show that magnetic field applied out-of-plane breaks the time -reversal symmetry and transforms the system's Wigner-Dyson class from root symplectic to unitary, increasing 8G by 2. Finally, we reveal that while Bi2Se3 is a strong TI, weak TI and metallic phases can be stabilized in presence of strain and disorder, and detected by monitoring the conductance fluctuations. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
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Editor |
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| |
Language |
|
Wos |
001173938400008 |
Publication Date |
2024-01-16 |
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| |
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 |
1 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.7; 2024 IF: 3.836 |
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| |
Call Number |
UA @ admin @ c:irua:204765 |
Serial |
9177 |
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| Permanent link to this record |
| |
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| |
|
Author |
Zhou, S.; Xu, W.; Xiao, Y.; Xiao, H.; Zhang, J.; Wang, Z.; He, G.; Liu, J.; Li, Y.; Peeters, F.M. |
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| |
Title |
Influence of neutron irradiation on X-ray diffraction, Raman spectrum and photoluminescence from pyrolytic and hot-pressed hexagonal boron nitride |
Type |
A1 Journal article |
| |
Year |
2023 |
Publication |
Journal of luminescence |
Abbreviated Journal |
|
|
| |
Volume |
263 |
Issue |
|
Pages |
120118-8 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
Hexagonal boron nitride (hBN) is considered as an ideal semiconductor material for solid-state neutron detector, owing to its large neutron scattering section because of the low atomic number of B and excellent physical properties. Here we study the influence of neutron irradiation on crystal structure and on intermediate energy state (IMES) levels induced by the presence of impurities and defects in hBN. Large-size and thick pyrolytic and hot-pressed hBN (PBN and HBN) samples, which can be directly applied for neutron detector devices, are prepared and bombarded by neutrons with different irradiation fluences. The SEM and TEM are used to observe the sample difference of PBN and HBN. X-ray diffraction and Raman spectroscopy are applied to examine the influence of neutron irradiation on lattice structures along different crystal directions of PBN and HBN samples. Photoluminescence (PL) is employed to study the effect of neutron irradiation on IMESs in these samples. We find that the neutron irradiation does not alter the in-plane lattice structures of both PBN and HBN samples, but it can release the inter-layer tensions induced by sample growth of the PBN samples. Interestingly and surprisingly, the neutron irradiation does not affect the IMES levels responsible for PL generation, where PL is attributed mainly from phonon-assisted radiative electron-hole coupling for both PBN and HBN samples. Furthermore, the results indicate that the neutron irradiation can weaken the effective carrier-phonon coupling and exciton transitions in PBN and HBN samples. Overall, both PBN and HBN samples show some degree of the resistance to neutron irradiation in terms of these basic physical properties. The interesting and important findings from this work can help us to gain an in-depth understanding of the influence of neutron irradiation on basic physical properties of hBN materials. These effects can be taken into account when designing and applying the hBN materials for neutron detectors. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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| |
Language |
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Wos |
001077086300001 |
Publication Date |
2023-08-09 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0022-2313 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.6 |
Times cited |
1 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.6; 2023 IF: 2.686 |
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| |
Call Number |
UA @ admin @ c:irua:200393 |
Serial |
9047 |
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| Permanent link to this record |
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Author |
Miranda, L.P.; da Costa, D.R.; Peeters, F.M.; Costa Filho, R.N. |
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| |
Title |
Vacancy clustering effect on the electronic and transport properties of bilayer graphene nanoribbons |
Type |
A1 Journal article |
| |
Year |
2023 |
Publication |
Nanotechnology |
Abbreviated Journal |
|
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| |
Volume |
34 |
Issue |
5 |
Pages |
055706-55710 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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| |
Abstract |
Experimental realizations of two-dimensional materials are hardly free of structural defects such as e.g. vacancies, which, in turn, modify drastically its pristine physical defect-free properties. In this work, we explore effects due to point defect clustering on the electronic and transport properties of bilayer graphene nanoribbons, for AA and AB stacking and zigzag and armchair boundaries, by means of the tight-binding approach and scattering matrix formalism. Evident vacancy concentration signatures exhibiting a maximum amplitude and an universality regardless of the system size, stacking and boundary types, in the density of states around the zero-energy level are observed. Our results are explained via the coalescence analysis of the strong sizeable vacancy clustering effect in the system and the breaking of the inversion symmetry at high vacancy densities, demonstrating a similar density of states for two equivalent degrees of concentration disorder, below and above the maximum value. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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| |
Language |
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Wos |
000886630000001 |
Publication Date |
2022-11-02 |
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Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.5 |
Times cited |
1 |
Open Access |
OpenAccess |
|
| |
Notes |
|
Approved |
Most recent IF: 3.5; 2023 IF: 3.44 |
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| |
Call Number |
UA @ admin @ c:irua:192030 |
Serial |
7350 |
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| Permanent link to this record |
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| |
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Author |
Wang, M.; Chang, K.; Wang, L.G.; Dai, N.; Peeters, F.M. |
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| |
Title |
Crystallographic plane tuning of charge and spin transport in semiconductor quantum wires |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
|
| |
Volume |
20 |
Issue |
36 |
Pages |
365202,1-365202,8 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
We investigate theoretically the charge and spin transport in quantum wires grown along different crystallographic planes in the presence of the Rashba spinorbit interaction (RSOI) and the Dresselhaus spinorbit interaction (DSOI). We find that changing the crystallographic planes leads to a variation of the anisotropy of the conductance due to a different interplay between the RSOI and DSOI, since the DSOI is induced by bulk inversion asymmetry, which is determined by crystallographic plane. This interplay depends sensitively on the crystallographic planes, and consequently leads to the anisotropic charge and spin transport in quantum wires embedded in different crystallographic planes. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
Bristol |
Editor |
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| |
Language |
|
Wos |
000269077000003 |
Publication Date |
2009-08-19 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.44 |
Times cited |
14 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.44; 2009 IF: 3.137 |
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| |
Call Number |
UA @ lucian @ c:irua:78933 |
Serial |
588 |
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| Permanent link to this record |
| |
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| |
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Author |
Milošević, M.M.; Tadić, M.; Peeters, F.M. |
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| |
Title |
Effects of lateral asymmetry on electronic structure of strained semiconductor nanorings in a magnetic field |
Type |
A1 Journal article |
| |
Year |
2008 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
|
| |
Volume |
19 |
Issue |
45 |
Pages |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
The influence of lateral asymmetry on the electronic structure and optical transitions in elliptical strained InAs nanorings is analyzed in the presence of a perpendicular magnetic field. Two-dimensional rings are assumed to have elliptical inner and outer boundaries oriented in mutually orthogonal directions. The influence of the eccentricity of the ring on the energy levels is analyzed. For large eccentricity of the ring, we do not find any AharonovBohm effect, in contrast to circular rings. Rather, the single-particle states of the electrons and the holes are localized as in two laterally coupled quantum dots formed in the lobes of the nanoring. Our work indicates that the control of shape is important for the existence of the AharonovBohm effect in semiconductor nanorings. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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| |
Language |
|
Wos |
000259922000016 |
Publication Date |
2008-10-09 |
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| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.44 |
Times cited |
11 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.44; 2008 IF: 3.446 |
|
| |
Call Number |
UA @ lucian @ c:irua:76874 |
Serial |
865 |
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| Permanent link to this record |
| |
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| |
|
Author |
Wu, Z.; Zhang, Z.Z.; Chang, K.; Peeters, F.M. |
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| |
Title |
Quantum tunneling through graphene nanorings |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
|
| |
Volume |
21 |
Issue |
18 |
Pages |
185201 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
We investigate theoretically quantum transport through graphene nanorings in the presence of a perpendicular magnetic field. Our theoretical results demonstrate that the graphene nanorings behave like a resonant tunneling device, contrary to the Aharonov-Bohm oscillations found in conventional semiconductor rings. The resonant tunneling can be tuned by the Fermi energy, the size of the central part of the graphene nanorings and the external magnetic field. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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| |
Language |
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Wos |
000276672100005 |
Publication Date |
2010-04-15 |
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| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.44 |
Times cited |
34 |
Open Access |
|
|
| |
Notes |
; This work is partly supported by the NSFC, the project from the Chinese Academy of Sciences, the bilateral project between China and Sweden, the Flemish Science Foundation (FWLO-Vl) and the Belgium Science Policy (IAP). ; |
Approved |
Most recent IF: 3.44; 2010 IF: 3.652 |
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| |
Call Number |
UA @ lucian @ c:irua:95614 |
Serial |
2796 |
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| Permanent link to this record |
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| |
|
Author |
Zhang, Z.Z.; Wu, Z.H.; Chang, K.; Peeters, F.M. |
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| |
Title |
Resonant tunneling through S- and U-shaped graphene nanoribbons |
Type |
A1 Journal article |
| |
Year |
2009 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
|
| |
Volume |
20 |
Issue |
41 |
Pages |
415203,1-415203,7 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
| |
Abstract |
We theoretically investigate resonant tunneling through S- and U-shaped nanostructured graphene nanoribbons. A rich structure of resonant tunneling peaks is found emanating from different quasi-bound states in the middle region. The tunneling current can be turned on and off by varying the Fermi energy. Tunability of resonant tunneling is realized by changing the width of the left and/or right leads and without the use of any external gates. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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| |
Language |
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Wos |
000269930100007 |
Publication Date |
2009-09-17 |
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| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
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Series Issue |
|
Edition |
|
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| |
ISSN |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.44 |
Times cited |
32 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.44; 2009 IF: 3.137 |
|
| |
Call Number |
UA @ lucian @ c:irua:79311 |
Serial |
2893 |
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| Permanent link to this record |
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| |
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Author |
Badalyan, S.M.; Peeters, F.M. |
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| |
Title |
Transport of magnetic edge states in a quantum wire exposed to a non-homogeneous magnetic field |
Type |
A1 Journal article |
| |
Year |
2001 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
|
| |
Volume |
12 |
Issue |
|
Pages |
570-576 |
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| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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| |
Abstract |
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| |
Address |
|
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| |
Corporate Author |
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Thesis |
|
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| |
Publisher |
|
Place of Publication |
Bristol |
Editor |
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| |
Language |
|
Wos |
000173305300041 |
Publication Date |
2002-08-25 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.44 |
Times cited |
5 |
Open Access |
|
|
| |
Notes |
|
Approved |
Most recent IF: 3.44; 2001 IF: 1.621 |
|
| |
Call Number |
UA @ lucian @ c:irua:37276 |
Serial |
3727 |
|
| Permanent link to this record |
| |
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| |
|
Author |
Scuracchio, P.; Dobry, A.; Costamagna, S.; Peeters, F.M. |
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| |
Title |
Tuning the polarized quantum phonon transmission in graphene nanoribbons |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
|
| |
Volume |
26 |
Issue |
26 |
Pages |
305401 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
|
| |
Abstract |
We propose systems that allow a tuning of the phonon transmission function T(omega) in graphene nanoribbons by using C-13 isotope barriers, antidot structures, and distinct boundary conditions. Phonon modes are obtained by an interatomic fifth-nearest neighbor force-constant model (5NNFCM) and T(omega) is calculated using the non-equilibrium Green's function formalism. We show that by imposing partial fixed boundary conditions it is possible to restrict contributions of the in-plane phonon modes to T(omega) at low energy. On the contrary, the transmission functions of out-of-plane phonon modes can be diminished by proper antidot or isotope arrangements. In particular, we show that a periodic array of them leads to sharp dips in the transmission function at certain frequencies omega(nu) which can be pre-defined as desired by controlling their relative distance and size. With this, we demonstrated that by adequate engineering it is possible to govern the magnitude of the ballistic transmission functions T(omega) in graphene nanoribbons. We discuss the implications of these results in the design of controlled thermal transport at the nanoscale as well as in the enhancement of thermo-electric features of graphene-based materials. |
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| |
Address |
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| |
Corporate Author |
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Thesis |
|
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| |
Publisher |
|
Place of Publication |
Bristol |
Editor |
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| |
Language |
|
Wos |
000358675900010 |
Publication Date |
2015-07-07 |
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0957-4484;1361-6528; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.44 |
Times cited |
5 |
Open Access |
|
|
| |
Notes |
; Discussions with C E Repetto, C R Stia and K H Michel are gratefully acknowledged. This work was partially supported by the Flemish Science Foundation (FWO-Vl) and PIP 11220090100392 of CONICET (Argentina). We acknowledge funding from the FWO (Belgium)-MINCyT (Argentina) collaborative research project. ; |
Approved |
Most recent IF: 3.44; 2015 IF: 3.821 |
|
| |
Call Number |
c:irua:127186 |
Serial |
3759 |
|
| Permanent link to this record |
| |
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| |
|
Author |
Milovanovic, S.P.; Peeters, F.M. |
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| |
Title |
Characterization of the size and position of electron-hole puddles at a graphene p-n junction |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
|
| |
Volume |
27 |
Issue |
27 |
Pages |
105203 |
|
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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| |
Abstract |
The effect of an electron-hole puddle on the electrical transport when governed by snake states in a bipolar graphene structure is investigated. Using numerical simulations we show that information on the size and position of the electron-hole puddle can be obtained using the dependence of the conductance on magnetic field and electron density of the gated region. The presence of the scatterer disrupts snake state transport which alters the conduction pattern. We obtain a simple analytical formula that connects the position of the electron-hole puddle with features observed in the conductance. The size of the electron-hole puddle is estimated from the magnetic field and gate potential that maximizes the effect of the puddle on the electrical transport. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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| |
Language |
English |
Wos |
000369849200003 |
Publication Date |
2016-02-11 |
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| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.44 |
Times cited |
3 |
Open Access |
|
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| |
Notes |
This work was supported by the Flemish Science Foundation (FWO-Vl) and the European Science Foundation (ESF) under the EUROCORES Program EuroGRAPHENE within the project CONGRAN. We acknowledge interesting correspondence with Thiti Taychatanapat. |
Approved |
Most recent IF: 3.44 |
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| |
Call Number |
c:irua:131907 |
Serial |
4025 |
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| Permanent link to this record |
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| |
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Author |
Cai, H.; Kang, J.; Sahin, H.; Chen, B.; Suslu, A.; Wu, K.; Peeters, F.; Meng, X.; Tongay, S. |
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| |
Title |
Exciton pumping across type-I gallium chalcogenide heterojunctions |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
|
| |
Volume |
27 |
Issue |
27 |
Pages |
065203 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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| |
Abstract |
Quasi-two-dimensional gallium chalcogenide heterostructures are created by transferring exfoliated few-layer GaSe onto bulk GaTe sheets. Luminescence spectroscopy measurements reveal that the light emission from underlying GaTe layers drastically increases on heterojunction regions where GaSe layers make contact with the GaTe. Density functional theory (DFT) and band offset calculations show that conduction band minimum (CBM) (valance band maximum (VBM)) values of GaSe are higher (lower) in energy compared to GaTe, forming type-I band alignment at the interface. Consequently, GaSe layers provide photo-excited electrons and holes to GaTe sheets through relatively large built-in potential at the interface, increasing overall exciton population and light emission from GaTe. Observed results are not specific to the GaSe/GaTe system but observed on GaS/GaSe heterolayers with type-I band alignment. Observed experimental findings and theoretical studies provide unique insights into interface effects across dissimilar gallium chalcogenides and offer new ways to boost optical performance by simple epitaxial coating. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
Bristol |
Editor |
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| |
Language |
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Wos |
000368897100008 |
Publication Date |
2016-01-13 |
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| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.44 |
Times cited |
15 |
Open Access |
|
|
| |
Notes |
; This work was supported by the Arizona State University seeding program, the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus-short Marie Curie Fellowship. We acknowledge the use of the John M Cowley Center for High Resolution Electron Microscopy at Arizona State University. The authors thank Anupum Pant for useful discussions. We gratefully acknowledge the use of the facilities at the LeRoy Eyring Center for Solid State Science at Arizona State University. S Tongay acknowledges support from DMR-1552220. ; |
Approved |
Most recent IF: 3.44 |
|
| |
Call Number |
UA @ lucian @ c:irua:131570 |
Serial |
4179 |
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| Permanent link to this record |
| |
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| |
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Author |
Kiymaz, D.; Yagmurcukardes, M.; Tomak, A.; Sahin, H.; Senger, R.T.; Peeters, F.M.; Zareie, H.M.; Zafer, C. |
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| |
Title |
Controlled growth mechanism of poly (3-hexylthiophene) nanowires |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
|
| |
Volume |
27 |
Issue |
27 |
Pages |
455604 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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| |
Abstract |
Synthesis of 1D-polymer nanowires by a self-assembly method using marginal solvents is an attractive technique. While the formation mechanism is poorly understood, this method is essential in order to control the growth of nanowires. Here we visualized the time-dependent assembly of poly (3-hexyl-thiophene-2,5-diyl) (P3HT) nanowires by atomic force microscopy and scanning tunneling microscopy. The assembly of P3HT nanowires was carried out at room temperature by mixing cyclohexanone (CHN), as a poor solvent, with polymer solution in 1,2-dichlorobenzene (DCB). Both pi-pi stacking and planarization, obtained at the mix volume ratio of P3HT (in DCB):CHN (10:7), were considered during the investigation. We find that the length of nanowires was determined by the ordering of polymers in the polymer repetition direction. Additionally, our density functional theory calculations revealed that the presence of DCB and CHN molecules that stabilize the structural distortions due to tail group of polymers was essential for the core-wire formation. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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| |
Language |
|
Wos |
000386132600003 |
Publication Date |
2016-10-11 |
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| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
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| |
Series Volume |
|
Series Issue |
|
Edition |
|
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| |
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.44 |
Times cited |
24 |
Open Access |
|
|
| |
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, the High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules Foundation. HS is supported by a FWO Pegasus-Long Marie Curie Fellowship. HS and RTS acknowledge support from TUBITAK through Project No. 114F397. Also, DA is supported by the Scientific Research Project Fund of Ege University (Project Nr: 12GEE011). ; |
Approved |
Most recent IF: 3.44 |
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| |
Call Number |
UA @ lucian @ c:irua:138159 |
Serial |
4350 |
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| Permanent link to this record |
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Author |
Tomak, A.; Bacaksiz, C.; Mendirek, G.; Sahin, H.; Hur, D.; Gorgun, K.; Senger, R.T.; Birer, O.; Peeters, F.M.; Zareie, H.M. |
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| |
Title |
Structural changes in a Schiff base molecular assembly initiated by scanning tunneling microscopy tip |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
|
| |
Volume |
27 |
Issue |
27 |
Pages |
335601 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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| |
Abstract |
We report the controlled self-organization and switching of newly designed Schiff base (E)-4-((4-(phenylethynyl) benzylidene) amino) benzenethiol (EPBB) molecules on a Au (111) surface at room temperature. Scanning tunneling microscopy and spectroscopy (STM/STS) were used to image and analyze the conformational changes of the EPBB molecules. The conformational change of the molecules was induced by using the STM tip while increasing the tunneling current. The switching of a domain or island of molecules was shown to be induced by the STM tip during scanning. Unambiguous fingerprints of the switching mechanism were observed via STM/STS measurements. Surface-enhanced Raman scattering was employed, to control and identify quantitatively the switching mechanism of molecules in a monolayer. Density functional theory calculations were also performed in order to understand the microscopic details of the switching mechanism. These calculations revealed that the molecular switching behavior stemmed from the strong interaction of the EPBB molecules with the STM tip. Our approach to controlling intermolecular mechanics provides a path towards the bottom-up assembly of more sophisticated molecular machines. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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| |
Language |
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Wos |
000383780500012 |
Publication Date |
2016-07-05 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.44 |
Times cited |
2 |
Open Access |
|
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| |
Notes |
; The authors acknowledge financial support from TUBITAK (PROJECT NO: 112T507). This work was also supported by the Flemish Science Foundation (FWO-Vl). Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid-Infrastructure). HS is supported by an FWO Pegasus Long Marie Curie Fellowship. ; |
Approved |
Most recent IF: 3.44 |
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| |
Call Number |
UA @ lucian @ c:irua:137155 |
Serial |
4363 |
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| Permanent link to this record |
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| |
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Author |
Petrovic, M.D.; Milovanović, S.P.; Peeters, F.M. |
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| |
Title |
Scanning gate microscopy of magnetic focusing in graphene devices : quantum versus classical simulation |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
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| |
Volume |
28 |
Issue |
28 |
Pages |
185202 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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| |
Abstract |
We compare classical versus quantum electron transport in recently investigated magnetic focusing devices (Bhandari et al 2016 Nano Lett. 16 1690) exposed to the perturbing potential of a scanning gate microscope (SGM). Using the Landauer-Buttiker formalism for a multi-terminal device, we calculate resistance maps that are obtained as the SGM tip is scanned over the sample. There are three unique regimes in which the scanning tip can operate (focusing, repelling, and mixed regime) which are investigated. Tip interacts mostly with electrons with cyclotron trajectories passing directly underneath it, leaving a trail of modified current density behind it. Other (indirect) trajectories become relevant when the tip is placed near the edges of the sample, and current is scattered between the tip and the edge. We point out that, in contrast to SGM experiments on gapped semiconductors, the STM tip can induce a pn junction in graphene, which improves contrast and resolution in SGM. We also discuss possible explanations for spatial asymmetry of experimentally measured resistance maps, and connect it with specific configurations of the measuring probes. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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| |
Language |
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Wos |
000399273800001 |
Publication Date |
2017-03-17 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.44 |
Times cited |
7 |
Open Access |
|
|
| |
Notes |
; This work was supported by the Methusalem program of the Flemish government. ; |
Approved |
Most recent IF: 3.44 |
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| |
Call Number |
UA @ lucian @ c:irua:143639 |
Serial |
4607 |
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| Permanent link to this record |
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Author |
Li, L.L.; Moldovan, D.; Xu, W.; Peeters, F.M. |
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| |
Title |
Electric-and magnetic-field dependence of the electronic and optical properties of phosphorene quantum dots |
Type |
A1 Journal article |
| |
Year |
2017 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
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| |
Volume |
28 |
Issue |
8 |
Pages |
085702 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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| |
Abstract |
Recently, black phosphorus quantum dots were fabricated experimentally. Motivated by these experiments, we theoretically investigate the electronic and optical properties of rectangular phosphorene quantum dots (RPQDs) in the presence of an in-plane electric field and a perpendicular magnetic field. The energy spectra and wave functions of RPQDs are obtained numerically using the tight-binding approach. We find edge states within the band gap of the RPQD which are well separated from the bulk states. In an undoped RPQD and for in-plane polarized light, due to the presence of well-defined edge states, we find three types of optical transitions which are between the bulk states, between the edge and bulk states, and between the edge states. The electric and magnetic fields influence the bulk-to-bulk, edge-to-bulk, and edge-to- edge transitions differently due to the different responses of bulk and edge states to these fields. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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| |
Language |
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Wos |
000403100700001 |
Publication Date |
2017-01-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.44 |
Times cited |
32 |
Open Access |
|
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| |
Notes |
; This work was financially supported by the China Scholarship Council (CSC), the Flemish Science Foundation (FWO-Vl), the National Natural Science Foundation of China (Grant Nos. 11304316 and 11574319), and by the Chinese Academy of Sciences (CAS). ; |
Approved |
Most recent IF: 3.44 |
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| |
Call Number |
UA @ lucian @ c:irua:144325 |
Serial |
4648 |
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| Permanent link to this record |
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Author |
Zhang, R.; Wu, Z.; Li, X.J.; Li, L.L.; Chen, Q.; Li, Y.-M.; Peeters, F.M. |
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Title |
Fano resonances in bilayer phosphorene nanoring |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
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| |
Volume |
29 |
Issue |
21 |
Pages |
215202 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
Tunable transport properties and Fano resonances are predicted in a circular bilayer phosphorene nanoring. The conductance exhibits Fano resonances with varying incident energy and applied perpendicular magnetic field. These Fano resonance peaks can be accurately fitted with the well known Fano curves. When a magnetic field is applied to the nanoring, the conductance oscillates periodically with magnetic field which is reminiscent of the Aharonov-Bohm effect. Fano resonances are tightly related to the discrete states in the central nanoring, some of which are tunable by the magnetic field. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000428920200001 |
Publication Date |
2018-03-08 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.44 |
Times cited |
4 |
Open Access |
|
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| |
Notes |
; This work was supported by Grant No. 2017YFA0303400 from the National Key R&D Program of China, the Flemish Science Foundation, the grants No. 2016YFE0110000, No. 2015CB921503, and No. 2016YFA0202300 from the MOST of China, the NSFC (Grants Nos. 11504366, 11434010, 61674145 and 61774168) and CAS (Grants No. QYZDJ-SSW-SYS001). ; |
Approved |
Most recent IF: 3.44 |
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| |
Call Number |
UA @ lucian @ c:irua:150713UA @ admin @ c:irua:150713 |
Serial |
4968 |
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| Permanent link to this record |
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Author |
Aierken, Y.; Sevik, C.; Gulseren, O.; Peeters, F.M.; Çakir, D. |
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| |
Title |
In pursuit of barrierless transition metal dichalcogenides lateral heterojunctions |
Type |
A1 Journal article |
| |
Year |
2018 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
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| |
Volume |
29 |
Issue |
29 |
Pages |
295202 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
There is an increasing need to understand interfaces between two-dimensional materials to realize an energy efficient boundary with low contact resistance and small heat dissipation. In this respect, we investigated the impact of charge and substitutional atom doping on the electronic transport properties of the hybrid metallic-semiconducting lateral junctions, formed between metallic (1T and 1T(d)) and semiconducting (1H) phases of MoS2 by means of first-principles and non-equilibrium Green function formalism based calculations. Our results clearly revealed the strong influence of the type of interface and crystallographic orientation of the metallic phase on the transport properties of these systems. The Schottky barrier height, which is the dominant mechanism for contact resistance, was found to be as large as 0.63 eV and 1.19 eV for holes and electrons, respectively. We found that armchair interfaces are more conductive as compared to zigzag termination due to the presence of the metallic Mo zigzag chains that are directed along the transport direction. In order to manipulate these barrier heights we investigated the influence of electron doping of the metallic part (i.e. 1T(d) -MoS2). We observed that the Fermi level of the hybrid system moves towards the conduction band of semiconducting 1H-MoS2 due to filling of 4d-orbital of metallic MoS2, and thus the Schottky barrier for electrons decreases considerably. Besides electron doping, we also investigated the effect of substitutional doping of metallic MoS2 by replacing Mo atoms with either Re or Ta. Due to its valency, Re (Ta) behaves as a donor (acceptor) and reduces the Schottky barrier for electrons (holes). Since Re and Ta based transition metal dichalcogenides crystallize in either the 1T(d) or 1T phase, substitutional doping with these atom favors the stabilization of the 1T(d) phase of MoS2. Co-doping of hybrid structure results in an electronic structure, which facilities easy dissociation of excitons created in the 1H part. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000432823800002 |
Publication Date |
2018-05-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
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Series Issue |
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Edition |
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| |
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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| |
Impact Factor |
3.44 |
Times cited |
4 |
Open Access |
|
|
| |
Notes |
; This work was supported by the bilateral project between the The Scientific and Technological Research Council of Turkey (TUBITAK) and FWO-Flanders, Flemish Science Foundation (FWO-VI) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TRGrid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. We acknowledge the support from TUBITAK (Grant No. 115F024). ; |
Approved |
Most recent IF: 3.44 |
|
| |
Call Number |
UA @ lucian @ c:irua:151451UA @ admin @ c:irua:151451 |
Serial |
5029 |
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| Permanent link to this record |
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Author |
Shah, N.A.; Li, L.L.; Mosallanejad, V.; Peeters, F.M.; Guo, G.-P. |
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| |
Title |
Transport characteristics of multi-terminal pristine and defective phosphorene systems |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
|
| |
Volume |
30 |
Issue |
45 |
Pages |
455705 |
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| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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| |
Abstract |
Atomic vacancies and nanopores act as local scattering centers and modify the transport properties of charge carriers in phosphorene nanoribbons (PNRs). We investigate the influence of such atomic defects on the electronic transport of multi-terminal PNR. We use the non-equilibrium Green's function approach within the tight-binding framework to calculate the transmission coefficient and the conductance. Terminals induce band mixing resulting in oscillations in the conductance. In the presence of atomic vacancies and nanopores the conductance between non-axial terminals exhibit constructive scattering, which is in contrast to mono-axial two-terminal systems where the conductance exhibits destructive scattering. This can be understood from the spatial local density of states of the transport modes in the system. Our results provide fundamental insights into the electronic transport in PNR-based multi-terminal systems and into the ability of atomic defects and nanopores through tuning the transport properties. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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| |
Language |
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Wos |
000483049100001 |
Publication Date |
2019-08-07 |
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| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
Series Volume |
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Series Issue |
|
Edition |
|
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| |
ISSN |
0957-4484 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
| |
Impact Factor |
3.44 |
Times cited |
8 |
Open Access |
|
|
| |
Notes |
; This work was supported by the National Key Research and Development Program of China (Grant No. 2016YFA0301700), the NNSFC (Grant No. 11625419), the Strategic Priority Research Program of the CAS (Grant Nos. XDB24030601 and XDB30000000), the Anhui initiative in Quantum information Technologies (Grants No. AHY080000), and the Flemish Science Foundation (FWO-Vl). This work was also supported by the Chinese Academy of Sciences and the World Academy of Science for the advancement of science in developing countries. ; |
Approved |
Most recent IF: 3.44 |
|
| |
Call Number |
UA @ admin @ c:irua:162760 |
Serial |
5429 |
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| Permanent link to this record |
