Records |
Author |
Abdullah, H.M.; da Costa, D.R.; Bahlouli, H.; Chaves, A.; Peeters, F.M.; Van Duppen, B. |
Title |
Electron collimation at van der Waals domain walls in bilayer graphene |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
Volume |
100 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
4 |
Pages |
045137 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We show that a domain wall separating single-layer graphene and AA-stacked bilayer graphene (AA-BLG) can be used to generate highly collimated electron beams which can be steered by a magnetic field. Two distinct configurations are studied, namely, locally delaminated AA-BLG and terminated AA-BLG whose terminal edge types are assumed to be either zigzag or armchair. We investigate the electron scattering using semiclassical dynamics and verify the results independently with wave-packet dynamics simulations. We find that the proposed system supports two distinct types of collimated beams that correspond to the lower and upper cones in AA-BLG. Our computational results also reveal that collimation is robust against the number of layers connected to AA-BLG and terminal edges. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000477892800005 |
Publication Date |
2019-07-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
12 |
Open Access |
|
Notes |
; H.M.A. and H.B. acknowledge the support of King Fahd University of Petroleum and Minerals under research group Project No. RG181001. D.R.C and A.C. were financially supported by the Brazilian Council for Research (CNPq) and CAPES foundation. B.V.D. is supported by a postdoctoral fellowship by the Research Foundation Flanders (FWO-Vl). ; |
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ admin @ c:irua:161887 |
Serial |
5410 |
Permanent link to this record |
|
|
|
Author |
Abdullah, H.M.; Van Duppen, B.; Zarenia, M.; Bahlouli, H.; Peeters, F.M. |
Title |
Quantum transport across van der Waals domain walls in bilayer graphene |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
29 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
42 |
Pages |
425303 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Bilayer graphene can exhibit deformations such that the two graphene sheets are locally detached from each other resulting in a structure consisting of domains with different van der Waals inter-layer coupling. Here we investigate how the presence of these domains affects the transport properties of bilayer graphene. We derive analytical expressions for the transmission probability, and the corresponding conductance, across walls separating different inter-layer coupling domains. We find that the transmission can exhibit a valley-dependent layer asymmetry and that the domain walls have a considerable effect on the chiral tunnelling properties of the charge carriers. We show that transport measurements allow one to obtain the strength with which the two layers are coupled. We perform numerical calculations for systems with two domain walls and find that the availability of multiple transport channels in bilayer graphene significantly modifies the conductance dependence on inter-layer potential asymmetry. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
London |
Editor |
|
Language |
|
Wos |
000410958400001 |
Publication Date |
2017-07-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.649 |
Times cited |
15 |
Open Access |
|
Notes |
; HMA and HB acknowledge the Saudi Center for Theoretical Physics (SCTP) for their generous support and the support of KFUPM under physics research group projects RG1502-1 and RG1502-2. This work is supported by the Flemish Science Foundation (FWO-VI) by a post-doctoral fellowship (BVD). ; |
Approved |
Most recent IF: 2.649 |
Call Number |
UA @ lucian @ c:irua:146664 |
Serial |
4793 |
Permanent link to this record |
|
|
|
Author |
Harrabi, K.; Gasmi, K.; Mekki, A.; Bahlouli, H.; Kunwar, S.; Milošević, M.V. |
Title |
Detection and measurement of picoseconds-pulsed laser energy using a NbTiN superconducting filament |
Type |
A1 Journal article |
Year |
2023 |
Publication |
IEEE transactions on applied superconductivity |
Abbreviated Journal |
|
Volume |
33 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5 |
Pages |
2400205-5 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
investigate non-equilibrium states created by a laser beam incident on a superconducting NbTiN filament subject to an electrical pulse at 4 K. In absence of the laser excitation, when the amplitude of the current pulse applied to the filament exceeds the critical current value, we monitored the delay time td that marks the collapse of the superconducting phase which is then followed by a voltage rise. We linked the delay time to the applied current using the time-dependent Ginzburg-Landau (TDGL) theory, which enabled us to deduce the cooling (or heat-removal) time from the fit to the experimental data. Subsequently, we exposed the filament biased with a current pulse close to its critical value to a focused laser beam, inducing a normal state in the impact region of the laser beam. We showed that the energy of the incident beam and the incurred delay time are related to each other by a simple expression, that enables direct measurement of incident beam energy by temporal monitoring of the transport response. This method can be extended for usage in single-photon detection regime, and be used for accurate calibration of an arbitrary light source. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000946265900016 |
Publication Date |
2023-02-14 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1051-8223 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.8 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 1.8; 2023 IF: NA |
Call Number |
UA @ admin @ c:irua:195110 |
Serial |
7295 |
Permanent link to this record |
|
|
|
Author |
Cheng, X.; Xu, W.; Wen, H.; Zhang, J.; Zhang, H.; Li, H.; Peeters, F.M.; Chen, Q. |
Title |
Electronic properties of 2H-stacking bilayer MoS₂ measured by terahertz time-domain spectroscopy |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Frontiers of physics |
Abbreviated Journal |
|
Volume |
18 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5 |
Pages |
53303-53311 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Bilayer (BL) molybdenum disulfide (MoS2) is one of the most important electronic structures not only in valleytronics but also in realizing twistronic systems on the basis of the topological mosaics in moire superlattices. In this work, BL MoS2 on sapphire substrate with 2H-stacking structure is fabricated. We apply the terahertz (THz) time-domain spectroscopy (TDS) for examining the basic optoelectronic properties of this kind of BL MoS2. The optical conductivity of BL MoS2 is obtained in temperature regime from 80 K to 280 K. Through fitting the experimental data with the theoretical formula, the key sample parameters of BL MoS2 can be determined, such as the electron density, the electronic relaxation time and the electronic localization factor. The temperature dependence of these parameters is examined and analyzed. We find that, similar to monolayer (ML) MoS2, BL MoS2 with 2H-stacking can respond strongly to THz radiation field and show semiconductor-like optoelectronic features. The theoretical calculations using density functional theory (DFT) can help us to further understand why the THz optoelectronic properties of BL MoS2 differ from those observed for ML MoS2. The results obtained from this study indicate that the THz TDS can be applied suitably to study the optoelectronic properties of BL MoS2 based twistronic systems for novel applications as optical and optoelectronic materials and devices. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000991955300002 |
Publication Date |
2023-05-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2095-0462; 2095-0470 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.5 |
Times cited |
3 |
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 7.5; 2023 IF: 2.579 |
Call Number |
UA @ admin @ c:irua:197398 |
Serial |
8818 |
Permanent link to this record |
|
|
|
Author |
Bertoni, G.; Grillo, V.; Brescia, R.; Ke, X.; Bals, S.; Catellani, A.; Li, H.; Manna, L. |
Title |
Direct determination of polarity, faceting, and core location in colloidal core/shell wurtzite semiconductor nanocrystals |
Type |
A1 Journal article |
Year |
2012 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
Volume |
6 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
7 |
Pages |
6453-6461 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
The ability to determine the atomic arrangement and termination of various facets of surfactant-coated nanocrystals is of great importance for understanding their growth mechanism and their surface properties and represents a critical piece of information that can be coupled to other experimental techniques and to calculations. This is especially appealing in the study of nanocrystals that can be grown in strongly anisotropic shapes, for which the relative growth rates of various facets can be influenced under varying reaction conditions. Here we show that in two representative cases of rod-shaped nanocrystals in the wurtzite phase (CdSe(core)/CdS(shell) and ZnSe(core)/ZnS(shell) nanorods) the terminations of the polar facets can be resolved unambiguously by combining advanced electron microscopy techniques, such as aberration-corrected HRTEM with exit wave reconstruction or aberration-corrected HAADF-STEM. The [0001] and [000-1] polar directions of these rods, which grow preferentially along their c-axis, are revealed clearly, with one side consisting of the Cd (or Zn)-terminated (0001) facet and the other side with a pronounced faceting due to Cd (or Zn)-terminated {10-1-1} facets. The lateral faceting of the rods is instead dominated by three nonpolar {10-10} facets. The core buried in the nanostructure can be localized in both the exit wave phase and HAADF-STEM images. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000306673800079 |
Publication Date |
2012-06-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
13.942 |
Times cited |
63 |
Open Access |
|
Notes |
The authors gratefully acknowledge funding from the European Research Council under grant number 240111 (NANO-ARCH) and the financial support from the Flemish Hercules 3 Programme for large infrastructures. G.B. and V.G. thank E. Rotunno for his help with STEM_CELL and IWFR. |
Approved |
Most recent IF: 13.942; 2012 IF: 12.062 |
Call Number |
UA @ lucian @ c:irua:101138 |
Serial |
710 |
Permanent link to this record |
|
|
|
Author |
Ozbal, G.; Senger, R.T.; Sevik, C.; Sevincli, H. |
Title |
Ballistic thermoelectric properties of monolayer semiconducting transition metal dichalcogenides and oxides |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Physical review B |
Abbreviated Journal |
|
Volume |
100 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
8 |
Pages |
085415 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Combining first-principles calculations with Landauer-Mittiker formalism, ballistic thermoelectric transport properties of semiconducting two-dimensional transition metal dichalcogenides (TMDs) and oxides (TMOs) (namely MX2 with M = Cr, Mo, W, Ti, Zr, Hf; X = O, S, Se, Te) are investigated in their 2H and 1T phases. Having computed structural, as well as ballistic electronic and phononic transport properties for all structures, we report the thermoelectric properties of the semiconducting ones. We find that 2H phases of four of the studied structures have very promising thermoelectric properties, unlike their 1T phases. The maximum room temperature p-type thermoelectric figure of merit (ZT) of 1.57 is obtained for 2H-HfSe2, which can be as high as 3.30 at T = 800 K. Additionally, 2H-ZrSe2, 2H-ZrTe2, and 2H-HfS2 have considerable ZT values (both nand p-type), that are above 1 at room temperature. The 1T phases of Zr and Hf-based oxides possess relatively high power factors, however their high lattice thermal conductance values limit their ZT values to below 1 at room temperature. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000480389100007 |
Publication Date |
2019-08-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:193773 |
Serial |
7549 |
Permanent link to this record |
|
|
|
Author |
Berdiyorov, G.R.; Bahlouli, H.; Peeters, F.M. |
Title |
Effect of substitutional impurities on the electronic transport properties of graphene |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Physica. E: Low-dimensional systems and nanostructures |
Abbreviated Journal |
Physica E |
Volume |
84 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
84 |
Pages |
22-26 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
Density-functional theory in combination with the nonequilibrium Green's function formalism is used to study the effect of substitutional doping on the electronic transport properties of hydrogen passivated zig-zag graphene nanoribbon devices. B, N and Si atoms are used to substitute carbon atoms located at the center or at the edge of the sample. We found that Si -doping results in better electronic transport as compared to the other substitutions. The transmission spectrum also depends on the location of the substitutional dopants: for single atom doping the largest transmission is obtained for edge substitutions, whereas substitutions in the middle of the sample give larger transmission for double carbon substitutions. The obtained results are explained in terms of electron localization in the system due to the presence of impurities. (C) 2016 Elsevier B.V. All rights reserved. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
North-Holland |
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000382489600004 |
Publication Date |
2016-05-24 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1386-9477 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.221 |
Times cited |
17 |
Open Access |
|
Notes |
; H.B. and F.M.P. acknowledge the support from King Fahd University of Petroleum and Minerals, Saudi Arabia, under research group project RG1329-1 and RG1329-2. G.R.B. acknowledges fruitful discussions with Dr. M.E. Madjet from Qatar Environment and Energy Research Institute. ; |
Approved |
Most recent IF: 2.221 |
Call Number |
UA @ lucian @ c:irua:135699 |
Serial |
4301 |
Permanent link to this record |