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Records |
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Author |
Vanderveken, F.; Ahmad, H.; Heyns, M.; Sorée, B.; Adelmann, C.; Ciubotaru, F. |
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Title |
Excitation and propagation of spin waves in non-uniformly magnetized waveguides |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Journal Of Physics D-Applied Physics |
Abbreviated Journal |
J Phys D Appl Phys |
| |
Volume |
53 |
Issue |
49 |
Pages |
495006 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The characteristics of spin waves in ferromagnetic waveguides with non-uniform magnetization have been investigated for situations where the shape anisotropy field of the waveguide is comparable to the external bias field. Spin-wave generation was realized by the magnetoelastic effect by applying normal and shear strain components, as well as by the Oersted field emitted by an inductive antenna. The magnetoelastic excitation field has a non-uniform profile over the width of the waveguide because of the non-uniform magnetization orientation, whereas the Oersted field remains uniform. Using micromagnetic simulations, we indicate that both types of excitation fields generate quantised width modes with both odd and even mode numbers as well as tilted phase fronts. We demonstrate that these effects originate from the average magnetization orientation with respect to the main axes of the magnetic waveguide. Furthermore, it is indicated that the excitation efficiency of the second-order mode generally surpasses that of the first-order mode due to their symmetry. The relative intensity of the excited modes can be controlled by the strain state as well as by tuning the dimensions of the excitation area. Finally, we demonstrate that the nonreciprocity of spin-wave radiation due to the chirality of an Oersted field generated by an inductive antenna is absent for magnetoelastic spin-wave excitation. |
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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 |
000575331600001 |
Publication Date |
2020-08-26 |
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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 |
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Edition |
|
| |
ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.4 |
Times cited |
1 |
Open Access |
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| |
Notes |
; This work has been supported by imec's industrial affiliate program on beyond-CMOS logic. It has also received funding from the European Union's Horizon 2020 research and innovation program within the FET-OPEN project CHIRON under grant agreement No. 801055. F V acknowledges financial support from the Research Foundation -Flanders (FWO) through grant No. 1S05719N. ; |
Approved  |
Most recent IF: 3.4; 2020 IF: 2.588 |
| |
Call Number |
UA @ admin @ c:irua:172641 |
Serial |
6515 |
| Permanent link to this record |
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Author |
Bafekry, A.; Yagmurcukardes, M.; Akgenc, B.; Ghergherehchi, M.; Nguyen, C. |
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Title |
Van der Waals heterostructures of MoS₂ and Janus MoSSe monolayers on graphitic boron-carbon-nitride (BC₃, C₃N, C₃N₄ and C₄N₃) nanosheets: a first-principles study |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Journal Of Physics D-Applied Physics |
Abbreviated Journal |
J Phys D Appl Phys |
| |
Volume |
|
Issue |
|
Pages |
1-10 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
In this work, we extensively investigate the structural and electronic properties of van der Waals heterostructures (HTs) constructed by MoS${2}$/$BC3$, MoS${2}$/$C3N$, MoS${2}$/$C3N4$, MoS${2}$/$C4N3$ and those using Janus MoSSe instead of MoS$2$ by performing density functional theory calculations. The electronic band structure calculations and the corresponding partial density of states reveal that the significant changes are driven by quite strong layer-layer interaction between the constitutive layers. Our results show that although all monolayers are semiconductors as free-standing layers, the MoS${2}$/$C3N$ and MoS${2}$/$C4N3$ bilayer HTs display metallic behavior as a consequence of transfer of charge carriers between two constituent layers. In addition, it is found that in MoSSe/$C3N$ bilayer HT, the degree of metallicity is affected by the interface chalcogen atom type when Se atoms are facing to $C3N$ layer, the overlap of the bands around the Fermi level is smaller. Moreover, the half-metallic magnetic $C4N3$ is shown to form magnetic half-metallic trilayer HT with MoS$2$ independent of the stacking sequence, i.e. whether it is sandwiched or two $C4N3$ layer encapsulate MoS$2$ layer. We further analyze the trilayer HTs in which MoS$2$ is encapsulated by two different monolayers and it is revealed that at least with one magnetic monolayer, it is possible to construct a magnetic trilayer. While the trilayer of $C4N3$/MoS${2}$/$BC3$ and $C4N3$/MoS${2}$/$C3N4$ exhibit half-metallic characteristics, $C4N3$/MoS${_2}$/$C3$N possesses a magnetic metallic ground state. Overall, our results reveal that holly structures of BCN crystals are suitable for heterostructure formation even over van der Waals type interaction which significantly changes electronic nature of the constituent layers. |
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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 |
000543344800001 |
Publication Date |
2020-04-07 |
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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 |
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Edition |
|
| |
ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.4 |
Times cited |
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Open Access |
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Notes |
|
Approved |
Most recent IF: 3.4; 2020 IF: 2.588 |
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Call Number |
UA @ admin @ c:irua:169754 |
Serial |
6651 |
| Permanent link to this record |
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Author |
Polanco, C.A.; Pandey, T.; Berlijn, T.; Lindsay, L. |
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Title |
Defect-limited thermal conductivity in MoS₂ |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Physical review materials |
Abbreviated Journal |
|
| |
Volume |
4 |
Issue |
1 |
Pages |
014004-14009 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
The wide measured range of thermal conductivities (k) for monolayer MoS2 and the corresponding incongruent calculated values in the literature all suggest that extrinsic defect thermal resistance is significant and varied in synthesized samples of this material. Here we present defect-mediated thermal transport calculations of MoS2 using interatomic forces derived from density functional theory combined with Green's function methods to describe phonon-point-defect interactions and a Peierls-Boltzmann formalism for transport. Conductivity calculations for bulk and monolayer MoS2 using different density functional formalisms are compared. Nonperturbative first-principles methods are used to describe defect-mediated spectral functions, scattering rates, and phonon k, particularly from sulfur vacancies (VS), and in the context of the plethora of measured and calculated literature values. We find that k of monolayer MoS2 is sensitive to phonon-VS scattering in the range of experimentally observed densities, and that first-principles k calculations using these densities can explain the range of measured values found in the literature. Furthermore, measured k values for bulk MoS2 are more consistent because VS defects are not as prevalent. |
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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 |
000619240000001 |
Publication Date |
2020-01-16 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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ISSN |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.4; 2020 IF: NA |
| |
Call Number |
UA @ admin @ c:irua:190510 |
Serial |
7757 |
| Permanent link to this record |
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Author |
Zhang, C.; Ren, K.; Wang, S.; Luo, Y.; Tang, W.; Sun, M. |
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Title |
Recent progress on two-dimensional van der Waals heterostructures for photocatalytic water splitting : a selective review |
Type |
A1 Journal article |
| |
Year |
2023 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
|
| |
Volume |
56 |
Issue |
48 |
Pages |
483001-483024 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Hydrogen production through photocatalytic water splitting is being developed swiftly to address the ongoing energy crisis. Over the past decade, with the rise of graphene and other two-dimensional (2D) materials, an increasing number of computational and experimental studies have focused on relevant van der Waals (vdW) semiconductor heterostructures for photocatalytic water splitting. In this review, the fundamental mechanism and distinctive performance of type-II and Z-scheme vdW heterostructure photocatalysts are presented. Accordingly, we have conducted a systematic review of recent studies focusing on candidates for photocatalysts, specifically vdW heterostructures involving 2D transition metal disulfides (TMDs), 2D Janus TMDs, and phosphorenes. The photocatalytic performance of these heterostructures and their suitability in theoretical scenarios are discussed based on their electronic and optoelectronic properties, particularly in terms of band structures, photoexcited carrier dynamics, and light absorption. In addition, various approaches for tuning the performance of these potential photocatalysts are illustrated. This strategic framework for constructing and modulating 2D heterostructure photocatalysts is expected to provide inspiration for addressing possible challenges in future studies. |
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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 |
001076327300001 |
Publication Date |
2023-08-30 |
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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 |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.4 |
Times cited |
|
Open Access |
|
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Notes |
|
Approved |
Most recent IF: 3.4; 2023 IF: 2.588 |
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Call Number |
UA @ admin @ c:irua:200353 |
Serial |
9081 |
| Permanent link to this record |
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Author |
Soenen, M.; Bacaksiz, C.; Menezes, R.M.; Milošević, M.V. |
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Title |
Stacking-dependent topological magnons in bilayer CrI₃ |
Type |
A1 Journal article |
| |
Year |
2023 |
Publication |
Physical review materials |
Abbreviated Journal |
|
| |
Volume |
7 |
Issue |
2 |
Pages |
024421-10 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Motivated by the potential of atomically thin magnets towards achieving tunable high-frequency magnonics, we detail the spin-wave dispersion of bilayer CrI3. We demonstrate that the magnonic behavior of the bilayer strongly depends on its stacking configuration and the interlayer magnetic ordering, where a topological band gap opens in the dispersion caused by the Dzyaloshinskii-Moriya and Kitaev interactions, classifying bilayer CrI3 as a topological magnon insulator. We further reveal that both the size and the topology of the band gap in a CrI3 bilayer with an antiferromagnetic interlayer ordering are tunable by an 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 |
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Editor |
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Language |
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Wos |
000943169600001 |
Publication Date |
2023-02-28 |
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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 |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.4 |
Times cited |
|
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 3.4; 2023 IF: NA |
| |
Call Number |
UA @ admin @ c:irua:195179 |
Serial |
7338 |
| Permanent link to this record |
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Author |
Soenen, M.; Milošević, M.V. |
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Title |
Tunable magnon topology in monolayer CrI₃ under external stimuli |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Physical review materials |
Abbreviated Journal |
|
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Volume |
7 |
Issue |
8 |
Pages |
084402-84409 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Two-dimensional (2D) honeycomb ferromagnets, such as monolayer chromium trihalides, are predicted to behave as topological magnon insulators, characterized by an insulating bulk and topologically protected edge states, giving rise to a thermal magnon Hall effect. Here we report the behavior of the topological magnons in monolayer CrI3 under external stimuli, including biaxial and uniaxial strain, electric gating, as well as in-plane and out-of-plane magnetic field, revealing that one can thereby tailor the magnetic states as well as the size and the topology of the magnonic bandgap. These findings broaden the perspective of using 2D magnetic materials to design topological magnonic devices. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
001052941600003 |
Publication Date |
2023-08-08 |
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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 |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record |
| |
Impact Factor |
3.4 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
|
Approved |
Most recent IF: 3.4; 2023 IF: NA |
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Call Number |
UA @ admin @ c:irua:199201 |
Serial |
8947 |
| Permanent link to this record |
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Author |
Lauwens, J.; Kerkhofs, L.; Sala, A.; Sorée, B. |
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Title |
Superconductor-semiconductor hybrid capacitance with a nonlinear charge-voltage profile |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
|
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Volume |
57 |
Issue |
2 |
Pages |
025301-25309 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Electronic devices that work in the quantum regime often employ hybrid nanostructures to bring about a nonlinear behaviour. The nonlinearity that these can provide has proven to be useful, in particular, for applications in quantum computation. Here we present a hybrid device that acts as a capacitor with a nonlinear charge-voltage relation. The device consists of a nanowire placed between the plates of a coplanar capacitor, with a co-parallel alignment. At low temperatures, due to the finite density of states on the nanowire, the charge distribution in the capacitor is uneven and energy-dependent, resulting in a charge-dependent effective capacitance. We study this system analytically and numerically, and show that the nonlinearity of the capacitance is significant enough to be utilized in circuit quantum electrodynamics. The resulting nonlinearity can be switched on, modulated, and switched off by an external potential, thus making this capacitive device highly versatile for uses in quantum computation. |
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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 |
001082883200001 |
Publication Date |
2023-09-29 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.4 |
Times cited |
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Open Access |
Not_Open_Access |
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Notes |
|
Approved |
Most recent IF: 3.4; 2024 IF: 2.588 |
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Call Number |
UA @ admin @ c:irua:200300 |
Serial |
9099 |
| Permanent link to this record |
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Author |
Blagojević, J.; Mijin, S.D.; Bekaert, J.; Opačić, M.; Liu, Y.; Milošević, M.V.; Petrović, C.; Popović, Z.V.; Lazarević, N. |
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Title |
Competition of disorder and electron-phonon coupling in 2H-TaSe2-xSx (0≤x≤2) as evidenced by Raman spectroscopy |
Type |
A1 Journal article |
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Year |
2024 |
Publication |
Physical review materials |
Abbreviated Journal |
|
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Volume |
8 |
Issue |
2 |
Pages |
024004-24008 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
The vibrational properties of 2H-TaSe<sub>2-x</sub>S<sub>x</sub> (0≤x≤2) single crystals were probed using Raman spectroscopy and density functional theory calculations. The end members revealed two out of four symmetry-predicted Raman active modes, together with the pronounced two-phonon structure, attributable to the enhanced electron-phonon coupling. Additional peaks become observable due to crystallographic disorder for the doped samples. The evolution of the E<sub>2</sub>g<sup>2</sup> mode Fano parameter reveals that the disorder has a weak impact on electron-phonon coupling, which is also supported by the persistence of two-phonon structure in doped samples. As such, this research provides thorough insights into the lattice properties, the effects of crystallographic disorder on Raman spectra, and the interplay of this disorder with the electron-phonon coupling in 2H-TaSe<sub>2-x</sub>S<sub>x</sub> compounds. |
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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 |
001171649400004 |
Publication Date |
2024-02-21 |
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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 |
2475-9953 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.4 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 3.4; 2024 IF: NA |
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Call Number |
UA @ admin @ c:irua:204404 |
Serial |
9141 |
| Permanent link to this record |
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Author |
Pinto, N.; McNaughton, B.; Minicucci, M.; Milošević, M.V.; Perali, A. |
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Title |
Electronic transport mechanisms correlated to structural properties of a reduced graphene oxide sponge |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Nanomaterials |
Abbreviated Journal |
Nanomaterials-Basel |
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Volume |
11 |
Issue |
10 |
Pages |
2503 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
We report morpho-structural properties and charge conduction mechanisms of a foamy “graphene sponge ”, having a density as low as & AP;0.07 kg/m3 and a carbon to oxygen ratio C:O & SIME; 13:1. The spongy texture analysed by scanning electron microscopy is made of irregularly-shaped millimetres-sized small flakes, containing small crystallites with a typical size of & SIME;16.3 nm. A defect density as high as & SIME;2.6 x 1011 cm-2 has been estimated by the Raman intensity of D and G peaks, dominating the spectrum from room temperature down to & SIME;153 K. Despite the high C:O ratio, the graphene sponge exhibits an insulating electrical behavior, with a raise of the resistance value at & SIME;6 K up to 5 orders of magnitude with respect to the room temperature value. A variable range hopping (VRH) conduction, with a strong 2D character, dominates the charge carriers transport, from 300 K down to 20 K. At T < 20 K, graphene sponge resistance tends to saturate, suggesting a temperature-independent quantum tunnelling. The 2D-VRH conduction originates from structural disorder and is consistent with hopping of charge carriers between sp2 defects in the plane, where sp3 clusters related to oxygen functional groups act as potential barriers.</p> |
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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 |
000713174500001 |
Publication Date |
2021-09-28 |
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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 |
2079-4991 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
3.553 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 3.553 |
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Call Number |
UA @ admin @ c:irua:184050 |
Serial |
6988 |
| Permanent link to this record |
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Author |
Joao, S.M.; Andelkovic, M.; Covaci, L.; Rappoport, T.G.; Lopes, J.M.V.P.; Ferreira, A. |
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Title |
KITE : high-performance accurate modelling of electronic structure and response functions of large molecules, disordered crystals and heterostructures |
Type |
A1 Journal article |
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Year |
2020 |
Publication |
Royal Society Open Science |
Abbreviated Journal |
Roy Soc Open Sci |
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Volume |
7 |
Issue |
2 |
Pages |
191809-191832 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
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Abstract |
We present KITE, a general purpose open-source tight-binding software for accurate real-space simulations of electronic structure and quantum transport properties of large-scale molecular and condensed systems with tens of billions of atomic orbitals (N similar to 10(10)). KITE's core is written in C++, with a versatile Python-based interface, and is fully optimized for shared memory multi-node CPU architectures, thus scalable, efficient and fast. At the core of KITE is a seamless spectral expansion of lattice Green's functions, which enables large-scale calculations of generic target functions with uniform convergence and fine control over energy resolution. Several functionalities are demonstrated, ranging from simulations of local density of states and photo-emission spectroscopy of disordered materials to large-scale computations of optical conductivity tensors and real-space wave-packet propagation in the presence of magneto-static fields and spin-orbit coupling. On-the-fly calculations of real-space Green's functions are carried out with an efficient domain decomposition technique, allowing KITE to achieve nearly ideal linear scaling in its multi-threading performance. Crystalline defects and disorder, including vacancies, adsorbates and charged impurity centres, can be easily set up with KITE's intuitive interface, paving the way to user-friendly large-scale quantum simulations of equilibrium and non-equilibrium properties of molecules, disordered crystals and heterostructures subject to a variety of perturbations and external conditions. |
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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 |
000518020200001 |
Publication Date |
2020-02-26 |
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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 |
2054-5703 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.5 |
Times cited |
19 |
Open Access |
OpenAccess |
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Notes |
; T.G.R. and A.F. acknowledge support from the Newton Fund and the Royal Society through the Newton Advanced Fellowship scheme (ref. no. NA150043). M.A. and L.C. acknowledge support from the Trans2DTMD FlagEra project and the VSC (Flemish Supercomputer Center). A.F. acknowledges support from the Royal Society through a University Research Fellowship (ref. nos. UF130385 and URF-R-191021) and an Enhancement Award (ref. no. RGF-EA-180276). T.G.R. acknowledges the support from the Brazilian agencies CNPq and FAPERJ and COMPETE2020, PORTUGAL2020, FEDER and the Portuguese Foundation for Science and Technology (FCT) through project POCI-01-0145-FEDER-028114. S.M.J. is supported by Fundacao para a Ciencia e Tecnologia (FCT) under the grant no. PD/BD/142798/ 2018. S.M.J. and J.M.V.P.L. acknowledge financial support from the FCT, COMPETE 2020 programme in FEDER component (European Union), through projects POCI-01-0145-FEDER028887 and UID/FIS/04650/2013. S.M.J. and J.M.V.P.L. further acknowledge financial support from FCT through national funds, co-financed by COMPETE-FEDER (grant no. M-ERANET2/0002/2016 -UltraGraf) under the Partnership Agreement PT2020. ; |
Approved |
Most recent IF: 3.5; 2020 IF: 2.243 |
| |
Call Number |
UA @ admin @ c:irua:167751 |
Serial |
6556 |
| 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 |
|
| |
Volume |
34 |
Issue |
5 |
Pages |
055706-55710 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| |
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 |
|
Editor |
|
| |
Language |
|
Wos |
000886630000001 |
Publication Date |
2022-11-02 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
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 |
| |
Call Number |
UA @ admin @ c:irua:192030 |
Serial |
7350 |
| Permanent link to this record |
| |
|
| |
|
Author |
Borkowski, R.; Straub, M.; Ou, Y.; Lefevre, Y.; Jelić, Ž.L.; Lanneer, W.; Kaneda, N.; Mahadevan, A.; Hueckstaedt, V.; van Veen, D.; Houtsma, V.; Coomans, W.; Bonk, R.; Maes, J. |
| |
Title |
FLCS-PON : a 100 Gbit/s flexible passive optical network: concepts and field trial |
Type |
A1 Journal article |
| |
Year |
2021 |
Publication |
Journal Of Lightwave Technology |
Abbreviated Journal |
J Lightwave Technol |
| |
Volume |
39 |
Issue |
16 |
Pages |
5314-5324 |
| |
Keywords |
A1 Journal article; Mass communications; Condensed Matter Theory (CMT) |
| |
Abstract |
We demonstrate concepts and results of a field trial for a flexible-rate passive optical network (FLCS-PON), which delivers bitrates up to 100 Gbit/s and allows for adaptations in the transmission method to match the users' channel conditions and optimize throughput. FLCS-PON builds on top of the hardware ecosystem that will be developed for ITU-T 50 Gbit/s PON and employs three new ingredients: optical network unit (ONU) grouping, flexible modulation format, and flexible forward error correction (FEC) code rate. Together, these techniques take advantage of the optical distribution network (ODN) statistics to realize a system capable of more than twofold throughput increase compared to the upcoming 50 Gbit/s PON, but still able to support a full array of deployed fiber edge cases, which are problematic for legacy PONs. In this paper we explain the concepts behind enabling techniques of FLCS-PON. We then report on a field trial over a deployed fiber infrastructure, using a system consisting of one FLCS-PON OLT and two ONUs. We report both pre- and post-forward-error-correction (post-FEC) performance of our system, demonstrating achievable net bitrate over an operator's fiber infrastructure. We realize a downlink transmission at double the speed of ITU-T 50 Gbit/s PON for ONUs exhibiting lower optical path loss (OPL), while simultaneously continue to support ONUs at high OPLs. We additionally realize a record-high 31.5 dB loss budget for 100 Gbit/s transmission using a direct-detection ONU with an optical preamplifier. |
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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 |
000692209800017 |
Publication Date |
2021-08-06 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0733-8724 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.671 |
Times cited |
|
Open Access |
Not_Open_Access |
| |
Notes |
|
Approved |
Most recent IF: 3.671 |
| |
Call Number |
UA @ admin @ c:irua:181586 |
Serial |
6995 |
| Permanent link to this record |
| |
|
| |
|
Author |
Kenawy, A.; Magnus, W.; Milošević, M.V.; Sorée, B. |
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Title |
Electronically tunable quantum phase slips in voltage-biased superconducting rings as a base for phase-slip flux qubits |
Type |
A1 Journal article |
| |
Year |
2020 |
Publication |
Superconductor Science & Technology |
Abbreviated Journal |
Supercond Sci Tech |
| |
Volume |
33 |
Issue |
12 |
Pages |
125002 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Quantum phase slips represent a coherent mechanism to couple flux states of a superconducting loop. Since their first direct observation, there have been substantial developments in building charge-insensitive quantum phase-slip circuits. At the heart of these devices is a weak link, often a nanowire, interrupting a superconducting loop. Owing to the very small cross-sectional area of such a nanowire, quantum phase slip rates in the gigahertz range can be achieved. Instead, here we present the use of a bias voltage across a superconducting loop to electrostatically induce a weak link, thereby amplifying the rate of quantum phase slips without physically interrupting the loop. Our simulations reveal that the bias voltage modulates the free energy barrier between subsequent flux states in a very controllable fashion, providing a route towards a phase-slip flux qubit with a broadly tunable transition frequency. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
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Editor |
|
| |
Language |
|
Wos |
000577207000001 |
Publication Date |
2020-09-16 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0953-2048 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.6 |
Times cited |
4 |
Open Access |
|
| |
Notes |
; ; |
Approved |
Most recent IF: 3.6; 2020 IF: 2.878 |
| |
Call Number |
UA @ admin @ c:irua:172643 |
Serial |
6503 |
| Permanent link to this record |
| |
|
| |
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Author |
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 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
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 |
|
Wos |
001077086300001 |
Publication Date |
2023-08-09 |
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Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
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 |
| |
Call Number |
UA @ admin @ c:irua:200393 |
Serial |
9047 |
| Permanent link to this record |
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Author |
Linek, J.; Wyszynski, M.; Müller, B.; Korinski, D.; Milošević, M.V.; Kleiner, R.; Koelle, D. |
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Title |
On the coupling of magnetic moments to superconducting quantum interference devices |
Type |
A1 Journal article |
| |
Year |
2024 |
Publication |
Superconductor science and technology |
Abbreviated Journal |
|
| |
Volume |
37 |
Issue |
2 |
Pages |
025010-25012 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
We investigate the coupling factor phi( mu) that quantifies the magnetic flux phi per magnetic moment mu of a point-like magnetic dipole that couples to a superconducting quantum interference device (SQUID). Representing the dipole by a tiny current-carrying (Amperian) loop, the reciprocity of mutual inductances of SQUID and Amperian loop provides an elegant way of calculating phi(mu)(r,e(mu)) vs. position r and orientation e(mu) of the dipole anywhere in space from the magnetic field B-J(r) produced by a supercurrent circulating in the SQUID loop. We use numerical simulations based on London and Ginzburg-Landau theory to calculate phi (mu) from the supercurrent density distributions in various superconducting loop geometries. We treat the far-field regime ( r greater than or similar to a= inner size of the SQUID loop) with the dipole placed on (oriented along) the symmetry axis of circular or square shaped loops. We compare expressions for phi (mu) from simple filamentary loop models with simulation results for loops with finite width w (outer size A > alpha), thickness d and London penetration depth lambda(L )and show that for thin ( d << alpha ) and narrow (w < alpha) loops the introduction of an effective loop size a(eff) in the filamentary loop-model expressions results in good agreement with simulations. For a dipole placed right in the center of the loop, simulations provide an expression phi(mu)(a,A,d,lambda(L)) that covers a wide parameter range. In the near-field regime (dipole centered at small distance z above one SQUID arm) only coupling to a single strip representing the SQUID arm has to be considered. For this case, we compare simulations with an analytical expression derived for a homogeneous current density distribution, which yields excellent agreement for lambda(L)>w,d . Moreover, we analyze the improvement of phi(mu) provided by the introduction of a narrow constriction in the SQUID arm below the magnetic dipole. |
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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 |
001145725500001 |
Publication Date |
2024-01-04 |
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Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
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Series Volume |
|
Series Issue |
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Edition |
|
| |
ISSN |
0953-2048 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
| |
Impact Factor |
3.6 |
Times cited |
|
Open Access |
Not_Open_Access |
| |
Notes |
|
Approved |
Most recent IF: 3.6; 2024 IF: 2.878 |
| |
Call Number |
UA @ admin @ c:irua:202759 |
Serial |
9067 |
| 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 |
| |
Volume |
105 |
Issue |
3 |
Pages |
035427 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
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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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
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Place of Publication |
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Editor |
|
| |
Language |
|
Wos |
000749375200002 |
Publication Date |
2022-01-28 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.7 |
Times cited |
3 |
Open Access |
Not_Open_Access |
| |
Notes |
|
Approved |
Most recent IF: 3.7 |
| |
Call Number |
UA @ admin @ c:irua:186387 |
Serial |
6977 |
| Permanent link to this record |
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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 |
| |
Volume |
105 |
Issue |
2 |
Pages |
024407 |
| |
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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Address |
|
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
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Editor |
|
| |
Language |
|
Wos |
000742384700001 |
Publication Date |
2022-01-06 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.7 |
Times cited |
13 |
Open Access |
Not_Open_Access: Available from 06.07.2202 |
| |
Notes |
|
Approved |
Most recent IF: 3.7 |
| |
Call Number |
UA @ admin @ c:irua:186514 |
Serial |
6991 |
| Permanent link to this record |
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Author |
Hassani, H.; Partoens, B.; Bousquet, E.; Ghosez, P. |
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Title |
First-principles study of lattice dynamical properties of the room-temperature P2₁/n and ground-state P2₁/c phases of WO₃ |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
105 |
Issue |
1 |
Pages |
014107 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Using first-principles density functional theory, we investigate the dynamical properties of the roomtemperature P21/n and ground-state P21/c phases of WO3. As a preliminary step, we assess the validity of various standard and hybrid functionals, concluding that the best description is achieved with the B1-WC hybrid functional while a reliable description can also be provided using the standard LDA functional. We also carefully rediscuss the structure and energetics of all experimentally observed and a few hypothetical metastable phases in order to provide deeper insight into the unusual sequence of phase transition of WO3 with temperature. Then, we provide a comprehensive theoretical study of the lattice dynamical properties of the P21/n and P21/c phases, reporting zone-center phonons, infrared and Raman spectra, as well as the full phonon dispersion curves, which attest to the dynamical stability of both phases. We carefully discuss the spectra, explaining the physical origin of their main features and evolution from one phase to another. We reveal a systematic connection between the dynamical and structural properties of WO3, highlighting that the number of peaks in the high-frequency range of the Raman spectrum appears as a fingerprint of the number of antipolar distortions that are present in the structure and a practical way to discriminate between the different phases. |
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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
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Editor |
|
| |
Language |
|
Wos |
000747398100004 |
Publication Date |
2022-01-24 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.7 |
Times cited |
5 |
Open Access |
Not_Open_Access |
| |
Notes |
|
Approved |
Most recent IF: 3.7 |
| |
Call Number |
UA @ admin @ c:irua:186388 |
Serial |
6994 |
| Permanent link to this record |
| |
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| |
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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 |
| |
Volume |
105 |
Issue |
11 |
Pages |
115423-115429 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
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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Address |
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| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000802810700002 |
Publication Date |
2022-03-22 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.7 |
Times cited |
3 |
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 3.7 |
| |
Call Number |
UA @ admin @ c:irua:188660 |
Serial |
7125 |
| Permanent link to this record |
| |
|
| |
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Author |
Shafiei, M.; Fazileh, F.; Peeters, F.M.; Milošević, M.V. |
| |
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 |
| |
Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
106 |
Issue |
3 |
Pages |
035119-7 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
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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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000832277500001 |
Publication Date |
2022-07-13 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.7 |
Times cited |
7 |
Open Access |
Not_Open_Access |
| |
Notes |
|
Approved |
Most recent IF: 3.7 |
| |
Call Number |
UA @ admin @ c:irua:189515 |
Serial |
7140 |
| Permanent link to this record |
| |
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| |
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Author |
Mirzakhani, M.; da Costa, D.R.; Peeters, F.M. |
| |
Title |
Isolated and hybrid bilayer graphene quantum rings |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
105 |
Issue |
11 |
Pages |
115430-11 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
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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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 |
000801209300006 |
Publication Date |
2022-03-28 |
| |
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 |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.7 |
Times cited |
4 |
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 3.7 |
| |
Call Number |
UA @ admin @ c:irua:188703 |
Serial |
7175 |
| Permanent link to this record |
| |
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| |
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Author |
Moura, V.N.; Dantas, D.S.; Farias, G.A.; Chaves, A.; Milošević, M.V. |
| |
Title |
Latent superconductivity at parallel interfaces in a superlattice dominated by another collective quantum phase |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
106 |
Issue |
1 |
Pages |
014516-10 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
We theoretically examine behavior of superconductivity at parallel interfaces separating the domains of another dominant collective excitation, such as charge density waves or spin density waves. Due to their competitive coupling in a two-component Ginzburg-Landau model, suppression of the dominant order parameter at the interfacial planes allows for nucleation of the (hidden) superconducting order parameter at those planes. In such a case, we demonstrate how the number of the parallel interfacial planes and the distance between them are linked to the number and the size of the emerging superconducting gaps in the system, as well as the versatility and temperature evolution of the possible superconducting phases. These findings bear relevance to a broad selection of known layered superconducting materials, as well as to further design of artificial (e.g., oxide) superlattices, where the interplay between competing order parameters paves the way towards otherwise unattainable superconducting states, some with enhanced superconducting critical temperature. |
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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 |
000834346000004 |
Publication Date |
2022-07-22 |
| |
Series Editor |
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Series Title |
|
Abbreviated Series Title |
|
| |
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 |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 3.7 |
| |
Call Number |
UA @ admin @ c:irua:189520 |
Serial |
7179 |
| Permanent link to this record |
| |
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| |
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Author |
Vizarim, N.P.; Souza, J.C.B.; Reichhardt, C.J.O.; Reichhardt, C.; Milošević, M.V.; Venegas, P.A. |
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Title |
Soliton motion in skyrmion chains : stabilization and guidance by nanoengineered pinning |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
105 |
Issue |
22 |
Pages |
224409-224412 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
Using a particle-based model we examine the depinning motion of solitons in skyrmion chains in quasi -onedimensional (1D) and two-dimensional (2D) systems containing embedded 1D interfaces. The solitons take the form of a particle or hole in a commensurate chain of skyrmions. Under an applied drive, just above a critical depinning threshold, the soliton moves with a skyrmion Hall angle of zero. For higher drives, the entire chain depins, and in a 2D system we observe that both the solitons and chain move at zero skyrmion Hall angle and then transition to a finite skyrmion Hall angle as the drive increases. In a 2D system with a 1D interface that is at an angle to the driving direction, there can be a reversal of the sign of the skyrmion Hall angle from positive to negative. Our results suggest that solitons in skyrmion systems could be used as information carriers in racetrack geometries that would avoid the drawbacks of finite skyrmion Hall angles. The soliton states become mobile at significantly lower drives than the depinning transition of the skyrmion chains themselves. |
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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 |
000823038900004 |
Publication Date |
2022-06-16 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.7 |
Times cited |
2 |
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 3.7 |
| |
Call Number |
UA @ admin @ c:irua:189671 |
Serial |
7209 |
| Permanent link to this record |
| |
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| |
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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. |
| |
Title |
Tunneling properties in α-T₃ lattices : effects of symmetry-breaking terms |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| |
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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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 |
000805195200001 |
Publication Date |
2022-04-01 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.7 |
Times cited |
|
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 3.7 |
| |
Call Number |
UA @ admin @ c:irua:188614 |
Serial |
7222 |
| Permanent link to this record |
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Author |
Gurel, T.; Altunay, Y.A.; Bulut, P.; Yildirim, S.; Sevik, C. |
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Title |
Comprehensive investigation of the extremely low lattice thermal conductivity and thermoelectric properties of BaIn₂Te₄ |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
106 |
Issue |
19 |
Pages |
195204-195210 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
Recently, an extremely low lattice thermal conductivity value has been reported for the alkali-based telluride material BaIn2Te4. The value is comparable with low-thermal conductivity metal chalcogenides, and the glass limit is highly intriguing. Therefore, to shed light on this issue, we performed first-principles phonon thermal transport calculations. We predicted highly anisotropic lattice thermal conductivity along different directions via the solution of the linearized phonon Boltzmann transport equation. More importantly, we determined several different factors as the main sources of the predicted ultralow lattice thermal conductivity of this crystal, such as the strong interactions between low-frequency optical phonons and acoustic phonons, small phonon group velocities, and lattice anharmonicity indicated by large negative mode Gruneisen parameters. Along with thermal transport calculations, we also investigated the electronic transport properties by accurately calculating the scattering mechanisms, namely the acoustic deformation potential, ionized impurity, and polar optical scatterings. The inclusion of spin-orbit coupling (SOC) for electronic structure is found to strongly affect the p-type Seebeck coefficients. Finally, we calculated the thermoelectric properties accurately, and the optimal ZT value of p-type doping, which originated from high Seebeck coefficients, was predicted to exceed unity after 700 K and have a direction averaged value of 1.63 (1.76 in the y-direction) at 1000 K around 2 x 1020 cm-3 hole concentration. For n-type doping, a ZT around 3.2 x 1019 cm-3 concentration was predicted to be a direction-averaged value of 1.40 (1.76 in the z-direction) at 1000 K, mostly originating from its high electron mobility. With the experimental evidence of high thermal stability, we showed that the BaIn2Te4 compound has the potential to be a promising mid- to high-temperature thermoelectric material for both p-type and n-type systems with appropriate doping. |
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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 |
000918954800001 |
Publication Date |
2022-11-21 |
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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 |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.7 |
Times cited |
|
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 3.7 |
| |
Call Number |
UA @ admin @ c:irua:194384 |
Serial |
7290 |
| Permanent link to this record |
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Author |
Lazarevic, N.; Baum, A.; Milosavljevic, A.; Peis, L.; Stumberger, R.; Bekaert, J.; Solajic, A.; Pesic, J.; Wang, A.; Scepanovic, M.; Abeykoon, A.M.M.; Milošević, M.V.; Petrovic, C.; Popovic, Z.V.; Hackl, R. |
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Title |
Evolution of lattice, spin, and charge properties across the phase diagram of Fe1-xSx |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
106 |
Issue |
9 |
Pages |
094510-94519 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| |
Abstract |
A Raman scattering study covering the entire substitution range of the FeSe1-xSx solid solution is presented. Data were taken as a function of sulfur concentration x for 0 <= x <= 1, of temperature and of scattering symmetry. All types of excitations including phonons, spins, and charges are analyzed in detail. It is observed that the energy and width of the iron-related B-1g phonon mode vary continuously across the entire range of sulfur substitution. The A(1g) chalcogenide mode disappears above x = 0.23 and reappears at a much higher energy for x = 0.69. In a similar way the spectral features appearing at finite doping in A(1g) symmetry vary discontinuously. The magnetic excitation centered at approximately 500 cm(-1) disappears above x = 0.23 where the A(1g) lattice excitations exhibit a discontinuous change in energy. The low-energy mode associated with fluctuations displays maximal intensity at the nematostructural transition and thus tracks the phase boundary. |
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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 |
000917933500004 |
Publication Date |
2022-09-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
|
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Series Volume |
|
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 |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 3.7 |
| |
Call Number |
UA @ admin @ c:irua:194397 |
Serial |
7304 |
| Permanent link to this record |
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Author |
Pascucci, F.; Conti, S.; Neilson, D.; Tempère, J.; Perali, A. |
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Title |
Josephson effect as a signature of electron-hole superfluidity in bilayers of van der Waals heterostructures |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
106 |
Issue |
22 |
Pages |
L220503-6 |
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Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) |
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Abstract |
We investigate a Josephson junction in an electron-hole superfluid in a double-layer transition metal dichalco-genide heterostructure. The observation of a critical tunneling current is a clear signature of superfluidity. In addition, we find the BCS-BEC crossover physics in the narrow barrier region controls the critical current across the entire system. The corresponding critical velocity, which is measurable in this system, has a maximum when the excitations pass from bosonic to fermionic. Remarkably, this occurs for the density at the boundary of the BEC to BCS-BEC crossover regime determined from the condensate fraction. This provides, in a semiconductor system, an experimental way to determine the position of this boundary. |
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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 |
000903924400007 |
Publication Date |
|
| |
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 |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.7 |
Times cited |
|
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 3.7 |
| |
Call Number |
UA @ admin @ c:irua:193402 |
Serial |
7316 |
| Permanent link to this record |
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Author |
Nulens, L.; Dausy, H.; Wyszynski, M.J.; Raes, B.; Van Bael, M.J.; Milošević, M.V.; Van de Vondel, J. |
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Title |
Metastable states and hidden phase slips in nanobridge SQUIDs |
Type |
A1 Journal article |
| |
Year |
2022 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
| |
Volume |
106 |
Issue |
13 |
Pages |
134518-134519 |
| |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
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Abstract |
We fabricated an asymmetric nanoscale SQUID consisting of one nanobridge weak link and one Dayem bridge weak link. The current phase relation of these particular weak links is characterized by multivaluedness and linearity. While the latter is responsible for a particular magnetic field dependence of the critical current (so-called vorticity diamonds), the former enables the possibility of different vorticity states (phase winding numbers) existing at one magnetic field value. In experiments the observed critical current value is stochastic in nature, does not necessarily coincide with the current associated with the lowest energy state and critically depends on the measurement conditions. In this paper, we unravel the origin of the observed metastability as a result of the phase dynamics happening during the freezing process and while sweeping the current. Moreover, we employ special measurement protocols to prepare the desired vorticity state and identify the (hidden) phase slip dynamics ruling the detected state of these nanodevices. In order to gain insights into the dynamics of the condensate and, more specifically the hidden phase slips, we performed time-dependent Ginzburg-Landau simulations. |
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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 |
000904657300007 |
Publication Date |
2022-10-31 |
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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 |
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Edition |
|
| |
ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.7 |
Times cited |
1 |
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 3.7 |
| |
Call Number |
UA @ admin @ c:irua:193393 |
Serial |
7321 |
| Permanent link to this record |
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Author |
Brammertz, G.; Oueslati, S.; Buffiere, M.; Bekaert, J.; El Anzeery, H.; Messaoud, K.B.; Sahayaraj, S.; Nuytten, T.; Koble, C.; Meuris, M.; Poortmans, J.; |
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Title |
Investigation of properties limiting efficiency in Cu2ZnSnSe4-based solar cells |
Type |
A1 Journal article |
| |
Year |
2015 |
Publication |
IEEE journal of photovoltaics |
Abbreviated Journal |
Ieee J Photovolt |
| |
Volume |
5 |
Issue |
5 |
Pages |
649-655 |
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Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
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Abstract |
We have investigated different nonidealities in Cu2ZnSnSe4CdSZnO solar cells with 9.7% conversion efficiency, in order to determine what is limiting the efficiency of these devices. Several nonidealities could be observed. A barrier of about 300 meV is present for electron flow at the absorberbuffer heterojunction leading to a strong crossover behavior between dark and illuminated currentvoltage curves. In addition, a barrier of about 130 meV is present at the Moabsorber contact, which could be reduced to 15 meV by inclusion of a TiN interlayer. Admittance spectroscopy results on the devices with the TiN backside contact show a defect level with an activation energy of 170 meV. Using all parameters extracted by the different characterization methods for simulations of the two-diode model including injection and recombination currents, we come to the conclusion that our devices are limited by the large recombination current in the depletion region. Potential fluctuations are present in the devices as well, but they do not seem to have a special degrading effect on the devices, besides a probable reduction in minority carrier lifetime through enhanced recombination through the band tail defects. |
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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 |
000353524800026 |
Publication Date |
2014-12-19 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
| |
ISSN |
2156-3381;2156-3403; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.712 |
Times cited |
13 |
Open Access |
|
| |
Notes |
; ; |
Approved |
Most recent IF: 3.712; 2015 IF: 3.165 |
| |
Call Number |
c:irua:123717 |
Serial |
1734 |
| Permanent link to this record |
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Author |
Cao, S.; Somsen, C.; Croitoru, M.; Schryvers, D.; Eggeler, G. |
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Title |
Focused ion beam/scanning electron microscopy tomography and conventional transmission electron microscopy assessment of Ni4Ti3 morphology in compression-aged Ni-rich Ni-Ti single crystals |
Type |
A1 Journal article |
| |
Year |
2010 |
Publication |
Scripta materialia |
Abbreviated Journal |
Scripta Mater |
| |
Volume |
62 |
Issue |
6 |
Pages |
399-402 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
| |
Abstract |
The size, morphology and configuration of Ni4Ti3 precipitates in a single-crystal NiTi alloy have been investigated by two-dimensional transmission electron microscopy-based image analysis and three-dimensional reconstruction from slice-and-view images obtained in a focused ion beam/scanning electron microscopy (FIB/SEM) dual-beam system. Average distances between the precipitates measured along the compression direction correlate well between both techniques, while particle shape and configuration data is best obtained from FIB/SEM. Precipitates form pockets of B2 of 0.54 ìm in the compression direction and 1 ìm perpendicular to the compression direction. |
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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 |
Oxford |
Editor |
|
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Language |
|
Wos |
000275072700020 |
Publication Date |
2009-12-04 |
| |
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 |
1359-6462; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
3.747 |
Times cited |
16 |
Open Access |
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 3.747; 2010 IF: 2.820 |
| |
Call Number |
UA @ lucian @ c:irua:79817 |
Serial |
1246 |
| Permanent link to this record |
