Records |
Author |
McNaughton, B.; Milošević, M.V.; Perali, A.; Pilati, S. |
Title |
Boosting Monte Carlo simulations of spin glasses using autoregressive neural networks |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Physical Review E |
Abbreviated Journal |
Phys Rev E |
Volume |
101 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5 |
Pages |
053312 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The autoregressive neural networks are emerging as a powerful computational tool to solve relevant problems in classical and quantum mechanics. One of their appealing functionalities is that, after they have learned a probability distribution from a dataset, they allow exact and efficient sampling of typical system configurations. Here we employ a neural autoregressive distribution estimator (NADE) to boost Markov chain Monte Carlo (MCMC) simulations of a paradigmatic classical model of spin-glass theory, namely, the two-dimensional Edwards-Anderson Hamiltonian. We show that a NADE can be trained to accurately mimic the Boltzmann distribution using unsupervised learning from system configurations generated using standard MCMC algorithms. The trained NADE is then employed as smart proposal distribution for the Metropolis-Hastings algorithm. This allows us to perform efficient MCMC simulations, which provide unbiased results even if the expectation value corresponding to the probability distribution learned by the NADE is not exact. Notably, we implement a sequential tempering procedure, whereby a NADE trained at a higher temperature is iteratively employed as proposal distribution in a MCMC simulation run at a slightly lower temperature. This allows one to efficiently simulate the spin-glass model even in the low-temperature regime, avoiding the divergent correlation times that plague MCMC simulations driven by local-update algorithms. Furthermore, we show that the NADE-driven simulations quickly sample ground-state configurations, paving the way to their future utilization to tackle binary optimization problems. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000535862000014 |
Publication Date |
2020-05-28 |
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 |
1539-3755; 1550-2376 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.366 |
Times cited |
15 |
Open Access |
|
Notes |
; The authors thank I. Murray, G. Carleo, and F. RicciTersenghi for useful discussions. Financial support from the FAR2018 project titled “Supervised machine learning for quantum matter and computational docking” of the University of Camerino and from the Italian MIUR under Project No. PRIN2017 CEnTraL 20172H2SC4 is gratefully acknowledged. S.P. also acknowledges the CINECA award under the ISCRA initiative, for the availability of high performance computing resources and support. M.V.M. gratefully acknowledges the Visiting Professorship program at the University of Camerino that facilitated the collaboration in this work. ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:170244 |
Serial |
6463 |
Permanent link to this record |
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Author |
Bekaert, J.; Khestanova, E.; Hopkinson, D.G.; Birkbeck, J.; Clark, N.; Zhu, M.; Bandurin, D.A.; Gorbachev, R.; Fairclough, S.; Zou, Y.; Hamer, M.; Terry, D.J.; Peters, J.J.P.; Sanchez, A.M.; Partoens, B.; Haigh, S.J.; Milošević, M.V.; Grigorieva, I., V |
Title |
Enhanced superconductivity in few-layer TaS₂ due to healing by oxygenation |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Nano Letters |
Abbreviated Journal |
Nano Lett |
Volume |
20 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5 |
Pages |
3808-3818 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
When approaching the atomically thin limit, defects and disorder play an increasingly important role in the properties of two-dimensional (2D) materials. While defects are generally thought to negatively affect superconductivity in 2D materials, here we demonstrate the contrary in the case of oxygenation of ultrathin tantalum disulfide (TaS2). Our first-principles calculations show that incorporation of oxygen into the TaS2 crystal lattice is energetically favorable and effectively heals sulfur vacancies typically present in these crystals, thus restoring the electronic band structure and the carrier density to the intrinsic characteristics of TaS2. Strikingly, this leads to a strong enhancement of the electron-phonon coupling, by up to 80% in the highly oxygenated limit. Using transport measurements on fresh and aged (oxygenated) few-layer TaS2, we found a marked increase of the superconducting critical temperature (T-c) upon aging, in agreement with our theory, while concurrent electron microscopy and electron-energy loss spectroscopy confirmed the presence of sulfur vacancies in freshly prepared TaS2 and incorporation of oxygen into the crystal lattice with time. Our work thus reveals the mechanism by which certain atomic-scale defects can be beneficial to superconductivity and opens a new route to engineer T-c in ultrathin materials. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000535255300114 |
Publication Date |
2020-04-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
1530-6984 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
10.8 |
Times cited |
16 |
Open Access |
|
Notes |
; This work was supported by Research Foundation-Flanders (FWO). J.Be. acknowledges support of a postdoctoral fellowship of the FWO. The computational resources and services used for the first-principles calculations in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government-department EWI. S.J.H., D.H., and S.F. would like to thank the Engineering and Physical Sciences Research Council (EPSRC) U.K (grants EP/R031711/1, EP/P009050/1 and the Graphene NOWNANO CDT) and the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement ERC-2016-STG-EvoluTEM-715502, the Hetero2D Synergy grant and EC-FET Graphene Flagship) for funding. We thank Diamond Light Source for access and support in use of the electron Physical Science Imaging Centre (Instrument E02 and proposal numbers EM19315 and MG21597) that contributed to the results presented here. ; |
Approved |
Most recent IF: 10.8; 2020 IF: 12.712 |
Call Number |
UA @ admin @ c:irua:170264 |
Serial |
6507 |
Permanent link to this record |
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Author |
Yagmurcukardes, M. |
Title |
Stable anisotropic single-layer of ReTe₂ : a first principles prediction |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Turkish Journal of Physics |
Abbreviated Journal |
|
Volume |
44 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5 |
Pages |
450-457 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In order to investigate the structural, vibrational, electronic, and mechanical features of single-layer ReTe2 first-principles calculations are performed. Dynamical stability analyses reveal that single-layer ReTe2 crystallize in a distorted phase while its 1H and 1T phases are dynamically unstable. Raman spectrum calculations show that single-layer distorted phase of ReTe2 exhibits 18 Raman peaks similar to those of ReS2 and ReSe2. Electronically, single-layer ReTe2 is shown to be an indirect gap semiconductor with a suitable band gap for optoelectronic applications. In addition, it is found that the formation of Re-units in the crystal induces anisotropic mechanical parameters. The in-plane stiffness and Poisson ratio are shown to be significantly dependent on the lattice orientation. Our findings indicate that single-layer form of ReTe2 can only crystallize in a dynamically stable distorted phase formed by the Re-units. Single-layer of distorted ReTe2 can be a potential in-plane anisotropic material for various nanotechnology applications. |
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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 |
000585330600004 |
Publication Date |
2020-09-20 |
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 |
1300-0101 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
; Computational resources were provided by the Scientific and Technological Research Council of Turkey (TUBITAK) Turkish Academic Network and Information Center (ULAKBIM), High Performance and Grid Computing Center (TR-Grid e-Infrastructure) and by Flemish Supercomputer Center (VSC). This work was supported by the Flemish Science Foundation (FWO-Vl) by a postdoctoral fellowship (M.Y.). ; |
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:174296 |
Serial |
6698 |
Permanent link to this record |
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Author |
Vanderveken, F.; Mulkers, J.; Leliaert, J.; Van Waeyenberge, B.; Sorée, B.; Zografos, O.; Ciubotaru, F.; Adelmann, C. |
Title |
Confined magnetoelastic waves in thin waveguides |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Physical Review B |
Abbreviated Journal |
Phys Rev B |
Volume |
103 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5 |
Pages |
054439 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The characteristics of confined magnetoelastic waves in nanoscale ferromagnetic magnetostrictive waveguides have been investigated by a combination of analytical and numerical calculations. The presence of both magnetostriction and inverse magnetostriction leads to the coupling between confined spin waves and elastic Lamb waves. Numerical simulations of the coupled system have been used to extract the dispersion relations of the magnetoelastic waves as well as their mode profiles. |
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 |
000627548800003 |
Publication Date |
2021-02-26 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2469-9969; 2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 3.836 |
Call Number |
UA @ admin @ c:irua:177607 |
Serial |
6976 |
Permanent link to this record |
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Author |
Tao, Z.H.; Dong, H.M.; Milošević, M.V.; Peeters, F.M.; Van Duppen, B. |
Title |
Tailoring dirac plasmons via anisotropic dielectric environment by design |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Physical Review Applied |
Abbreviated Journal |
Phys Rev Appl |
Volume |
16 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5 |
Pages |
054030 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Dirac plasmons in a two-dimensional (2D) crystal are strongly affected by the dielectric properties of the environment, due to interaction of their electric field lines with the surrounding medium. Using graphene as a 2D reservoir of free carriers, one can engineer a material configuration that provides an anisotropic environment to the plasmons. In this work, we discuss the physical properties of Dirac plasmons in graphene surrounded by an arbitrary anisotropic dielectric and exemplify how h-BN-based heterostructures can be designed to bear the required anisotropic characteristics. We calculate how dielec-tric anisotropy impacts the spatial propagation of the plasmons and find that an anisotropy-induced plasmon mode emerges, together with a damping pathway, that stem from the out-of-plane off-diagonal elements in the dielectric tensor. Furthermore, we find that one can create hyperbolic plasmons by inher-iting the dielectric hyperbolicity of the designed material environment. Strong control over plasmon propagation patterns can be realized in a similar manner. Finally, we show that in this way one can also control the polarization of the light-matter excitations that constitute the plasmon. Taken together, our results promote the design of the dielectric environment as an effective path to tailor the plasmonic response of graphene on the nanoscopic level. |
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 |
000720372500002 |
Publication Date |
2021-11-15 |
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 |
2331-7019 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.808 |
Times cited |
1 |
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 4.808 |
Call Number |
UA @ admin @ c:irua:184063 |
Serial |
7028 |
Permanent link to this record |
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Author |
Yagmurcukardes, N.; Bayram, A.; Aydin, H.; Yagmurcukardes, M.; Acikbas, Y.; Peeters, F.M.; Celebi, C. |
Title |
Anisotropic etching of CVD grown graphene for ammonia sensing |
Type |
A1 Journal article |
Year |
2022 |
Publication |
IEEE sensors journal |
Abbreviated Journal |
Ieee Sens J |
Volume |
22 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5 |
Pages |
3888-3895 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Bare chemical vapor deposition (CVD) grown graphene (GRP) was anisotropically etched with various etching parameters. The morphological and structural characterizations were carried out by optical microscopy and the vibrational properties substrates were obtained by Raman spectroscopy. The ammonia adsorption and desorption behavior of graphene-based sensors were recorded via quartz crystal microbalance (QCM) measurements at room temperature. The etched samples for ambient NH3 exhibited nearly 35% improvement and showed high resistance to humidity molecules when compared to bare graphene. Besides exhibiting promising sensitivity to NH3 molecules, the etched graphene-based sensors were less affected by humidity. The experimental results were collaborated by Density Functional Theory (DFT) calculations and it was shown that while water molecules fragmented into H and O, NH3 interacts weakly with EGPR2 sample which reveals the enhanced sensing ability of EGPR2. Apparently, it would be more suitable to use EGRP2 in sensing applications due to its sensitivity to NH3 molecules, its stability, and its resistance to H2O molecules in humid ambient. |
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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 |
000766276000010 |
Publication Date |
2022-01-24 |
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 |
1530-437x; 1558-1748 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.3 |
Times cited |
2 |
Open Access |
Not_Open_Access |
Notes |
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Approved |
Most recent IF: 4.3 |
Call Number |
UA @ admin @ c:irua:187257 |
Serial |
7126 |
Permanent link to this record |
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Author |
Harrabi, K.; Gasmi, K.; Mekki, A.; Bahlouli, H.; Kunwar, S.; Milošević, M.V. |
Title |
Detection and measurement of picoseconds-pulsed laser energy using a NbTiN superconducting filament |
Type |
A1 Journal article |
Year |
2023 |
Publication |
IEEE transactions on applied superconductivity |
Abbreviated Journal |
|
Volume |
33 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5 |
Pages |
2400205-5 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
investigate non-equilibrium states created by a laser beam incident on a superconducting NbTiN filament subject to an electrical pulse at 4 K. In absence of the laser excitation, when the amplitude of the current pulse applied to the filament exceeds the critical current value, we monitored the delay time td that marks the collapse of the superconducting phase which is then followed by a voltage rise. We linked the delay time to the applied current using the time-dependent Ginzburg-Landau (TDGL) theory, which enabled us to deduce the cooling (or heat-removal) time from the fit to the experimental data. Subsequently, we exposed the filament biased with a current pulse close to its critical value to a focused laser beam, inducing a normal state in the impact region of the laser beam. We showed that the energy of the incident beam and the incurred delay time are related to each other by a simple expression, that enables direct measurement of incident beam energy by temporal monitoring of the transport response. This method can be extended for usage in single-photon detection regime, and be used for accurate calibration of an arbitrary light source. |
Address |
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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 |
000946265900016 |
Publication Date |
2023-02-14 |
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 |
1051-8223 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.8 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 1.8; 2023 IF: NA |
Call Number |
UA @ admin @ c:irua:195110 |
Serial |
7295 |
Permanent link to this record |
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Author |
Miranda, L.P.; da Costa, D.R.; Peeters, F.M.; Costa Filho, R.N. |
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 ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
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. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000886630000001 |
Publication Date |
2022-11-02 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0957-4484 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.5 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 3.5; 2023 IF: 3.44 |
Call Number |
UA @ admin @ c:irua:192030 |
Serial |
7350 |
Permanent link to this record |
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Author |
Avetisyan, A.A.; Ghazaryan, A.V.; Djotyan, A.P.; Kirakosyan, A.A.; Moulopoulos, K. |
Title |
Magnetoexcitons in semiconductor quantum rings with complicated (Kane's) dispersion law |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Acta physica Polonica: A: general physics, solid state physics, applied physics
T2 – 4th Workshop on Quantum Chaos and Localisation Phenomena, MAY 22-24, 2009, Polish Acad Sci, Ctr Theoret Phys, Inst Phys, Polish Acad Sci, Ctr Theoret Phys, Inst Phys, War |
Abbreviated Journal |
|
Volume |
116 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5 |
Pages |
826-828 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The influence of the nonparabolicity of charge carriers dispersion law (Kane's dispersion) on a magnetoexciton energy spectrum in InSb quantum rings is theoretically investigated The analytical expression for the energy spectrum of exciton in a narrow-gap semiconductor nanoring in a magnetic field is obtained. The Aharonov – Bohm oscillations in the energy of excited states are studied. |
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 |
000273091200015 |
Publication Date |
2016-02-25 |
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 |
0587-4246 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
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Open Access |
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Notes |
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Approved |
no |
Call Number |
UA @ admin @ c:irua:172293 |
Serial |
8193 |
Permanent link to this record |
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Author |
Conti, S.; Perali, A.; Hamilton, A.R.; Milošević, M.V.; Peeters, F.M.; Neilson, D. |
Title |
Chester supersolid of spatially indirect excitons in double-layer semiconductor heterostructures |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Physical review letters |
Abbreviated Journal |
|
Volume |
130 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5 |
Pages |
057001-57006 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
A supersolid, a counterintuitive quantum state in which a rigid lattice of particles flows without resistance, has to date not been unambiguously realized. Here we reveal a supersolid ground state of excitons in a double-layer semiconductor heterostructure over a wide range of layer separations outside the focus of recent experiments. This supersolid conforms to the original Chester supersolid with one exciton per supersolid site, as distinct from the alternative version reported in cold-atom systems of a periodic density modulation or clustering of the superfluid. We provide the phase diagram augmented by the supersolid. This new phase appears at layer separations much smaller than the predicted exciton normal solid, and it persists up to a solid-solid transition where the quantum phase coherence collapses. The ranges of layer separations and exciton densities in our phase diagram are well within reach of the current experimental capabilities. |
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 |
000968650900001 |
Publication Date |
2023-02-01 |
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 |
0031-9007; 1079-7114 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
8.6 |
Times cited |
|
Open Access |
Not_Open_Access |
Notes |
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Approved |
Most recent IF: 8.6; 2023 IF: 8.462 |
Call Number |
UA @ admin @ c:irua:196742 |
Serial |
8817 |
Permanent link to this record |
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Author |
Cheng, X.; Xu, W.; Wen, H.; Zhang, J.; Zhang, H.; Li, H.; Peeters, F.M.; Chen, Q. |
Title |
Electronic properties of 2H-stacking bilayer MoS₂ measured by terahertz time-domain spectroscopy |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Frontiers of physics |
Abbreviated Journal |
|
Volume |
18 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5 |
Pages |
53303-53311 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Bilayer (BL) molybdenum disulfide (MoS2) is one of the most important electronic structures not only in valleytronics but also in realizing twistronic systems on the basis of the topological mosaics in moire superlattices. In this work, BL MoS2 on sapphire substrate with 2H-stacking structure is fabricated. We apply the terahertz (THz) time-domain spectroscopy (TDS) for examining the basic optoelectronic properties of this kind of BL MoS2. The optical conductivity of BL MoS2 is obtained in temperature regime from 80 K to 280 K. Through fitting the experimental data with the theoretical formula, the key sample parameters of BL MoS2 can be determined, such as the electron density, the electronic relaxation time and the electronic localization factor. The temperature dependence of these parameters is examined and analyzed. We find that, similar to monolayer (ML) MoS2, BL MoS2 with 2H-stacking can respond strongly to THz radiation field and show semiconductor-like optoelectronic features. The theoretical calculations using density functional theory (DFT) can help us to further understand why the THz optoelectronic properties of BL MoS2 differ from those observed for ML MoS2. The results obtained from this study indicate that the THz TDS can be applied suitably to study the optoelectronic properties of BL MoS2 based twistronic systems for novel applications as optical and optoelectronic materials and devices. |
Address |
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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 |
000991955300002 |
Publication Date |
2023-05-22 |
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 |
2095-0462; 2095-0470 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.5 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 7.5; 2023 IF: 2.579 |
Call Number |
UA @ admin @ c:irua:197398 |
Serial |
8818 |
Permanent link to this record |
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Author |
Bellizotti Souza, J.C.; Vizarim, N.P.; Reichhardt, C.J.O.; Reichhardt, C.; Venegas, P.A. |
Title |
Spontaneous skyrmion conformal lattice and transverse motion during dc and ac compression |
Type |
A1 Journal article |
Year |
2023 |
Publication |
New journal of physics |
Abbreviated Journal |
|
Volume |
25 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5 |
Pages |
053020-15 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We use atomistic-based simulations to investigate the behavior of ferromagnetic skyrmions being continuously compressed against a rigid wall under dc and ac drives. The compressed skyrmions can be annihilated close to the wall and form a conformal crystal with both a size and a density gradient, making it distinct from conformal crystals observed previously for superconducting vortices and colloidal particles. For both dc and ac driving, the skyrmions can move transverse to the compression direction due to a combination of density and size gradients. Forces in the compression direction are converted by the Magnus force into transverse motion. Under ac driving, the amount of skyrmion annihilation is reduced and we find a skyrmion Magnus ratchet pump. We also observe shear banding in which skyrmions near the wall move up to twice as fast as skyrmions further from the wall. When we vary the magnitude of the applied drive, we find a critical current above which the skyrmions are completely annihilated during a time scale that depends on the magnitude of the drive. By varying the magnetic parameters, we find that the transverse motion is strongly dependent on the skyrmion size. Smaller skyrmions are more rigid, which interferes with the size gradient and destroys the transverse motion. We also confirm the role of the size gradient by comparing our atomistic simulations with a particle-based model, where we find that the transverse motion is only transient. Our results are relevant for applications where skyrmions encounter repulsive magnetic walls, domain walls, or interfaces. |
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 |
000994003200001 |
Publication Date |
2023-05-11 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1367-2630 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.3 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 3.3; 2023 IF: 3.786 |
Call Number |
UA @ admin @ c:irua:197365 |
Serial |
8934 |
Permanent link to this record |
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|
|
Author |
Dong, H.M.; Liang, H.P.; Tao, Z.H.; Duan, Y.F.; Milošević, M.V.; Chang, K. |
Title |
Interface thermal conductivities induced by van der Waals interactions |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
|
Volume |
26 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5 |
Pages |
4047-4051 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The interface heat transfer of two layers induced by van der Waals (vdW) contacts is theoretically investigated, based on first-principles calculations at low temperatures. The results suggest that out-of-plane acoustic phonons with low frequencies dominate the interface thermal transport due to the vdW interaction. The interface thermal conductivity is proportional to the cubic of temperature at very low temperatures, but becomes linearly proportional to temperature as temperature increases. We show that manipulating the strain alters vdW coupling, leading to increased interfacial thermal conductivity at the interface. Our findings provide valuable insights into the interface heat transport in vdW heterostructures and support further design and optimization of electronic and optoelectronic nanodevices based on vdW contacts. The heat transfer induced by van der Waals contacts is dominated by ZA phonons. The interface thermal conductivity is proportional to the cubic of temperature, but becomes linearly proportional to temperature as temperature increases. |
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 |
001142323400001 |
Publication Date |
2024-01-09 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1463-9076; 1463-9084 |
ISBN |
|
Additional Links |
UA library record; WoS full record |
Impact Factor |
3.3 |
Times cited |
|
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: 3.3; 2024 IF: 4.123 |
Call Number |
UA @ admin @ c:irua:202795 |
Serial |
9050 |
Permanent link to this record |
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|
|
Author |
Shanenko, A.A.; Ivanov, V.A. |
Title |
Effects of confining interaction in meso-superconductors |
Type |
A1 Journal article |
Year |
2004 |
Publication |
Physics letters : A |
Abbreviated Journal |
Phys Lett A |
Volume |
322 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5-6 |
Pages |
384-389 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
This Letter presents a generalized Ginzburg-Landau equation for the superconducting order parameter which includes the terms resulting from the confining interaction associated with the specimen boundary. While the original Ginzburg-Landau theory had been developed for a bulk superconductor, this generalization is meant for study of a meso-superconductor. (C) 2004 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000220123600018 |
Publication Date |
2004-02-05 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0375-9601; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.772 |
Times cited |
1 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.772; 2004 IF: 1.454 |
Call Number |
UA @ lucian @ c:irua:103244 |
Serial |
859 |
Permanent link to this record |
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|
|
Author |
Verberck, B.; Heresanu, V.; Rouziere, S.; Cambedouzou, J.; Launois, P.; Kovats, E.; Pekker, S.; Vliegenthart, G.A.; Michel, K.H.; Gompper, G. |
Title |
Fullerene-cubane : X-ray scattering experiments and Monte Carlo simulations |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Fullerenes, nanotubes, and carbon nanostructures
T2 – 8th Biennial International Workshop on Fullerenes and Atomic Clusters, (IWFAC 2007), JUL 02-06, 2007, St Petersburg, RUSSIA |
Abbreviated Journal |
Fuller Nanotub Car N |
Volume |
16 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5-6 |
Pages |
293-300 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
We report single-crystal X-ray diffuse scattering measurements on C-60.C8H8 fullerene-cubane showing that the C-60 molecules are orientationally disordered at 300 and 150K and get ordered at low temperatures. Monte Carlo simulations provide further insight in the orientational behavior of both C-60 and C8H8 molecules; low-temperature molecular orientations are predicted. |
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 |
000259645200003 |
Publication Date |
2008-09-28 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1536-383X;1536-4046; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.35 |
Times cited |
6 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.35; 2008 IF: 0.680 |
Call Number |
UA @ lucian @ c:irua:102640 |
Serial |
1295 |
Permanent link to this record |
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|
|
Author |
Silva, F.C.O.; Menezes, R.M.; Cabral, L.R.E.; de Souza Silva, C.C. |
Title |
Formation and stability of conformal spirals in confined 2D crystals |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Journal Of Physics-Condensed Matter |
Abbreviated Journal |
J Phys-Condens Mat |
Volume |
32 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
50 |
Pages |
505401 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We investigate the ground-state and dynamical properties of nonuniform two-dimensional (2D) clusters of long-range interacting particles. We demonstrate that, when the confining external potential is designed to produce an approximate 1/ r 2 density profile, the particles crystallize into highly ordered structures featuring spiral crystalline lines. Despite the strong inhomogeneity of the observed configurations, most of them are characterized by small density of topological defects, typical of conformal crystals, and the net topological charge induced by the simply-connected geometry of the system is concentrated near the cluster center. These crystals are shown to be robust with respect to thermal fluctuations up to a certain threshold temperature, above which the net charge is progressively redistributed from the center to the rest of the system and the topological order is lost. The crystals are also resilient to the shear stress produced by a small nonuniform azimuthal force field, rotating as a rigid body (RB). For larger forces, topological defects proliferate and the RB rotation gives place to plastic flow. |
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 |
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Publication Date |
2020-08-19 |
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 |
0953-8984 |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
2.7 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.7; 2020 IF: 2.649 |
Call Number |
UA @ admin @ c:irua:191093 |
Serial |
7978 |
Permanent link to this record |
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|
|
Author |
Pereira, J.R.V.; Tunes, T.M.; De Arruda, A.S.; Godoy, M. |
Title |
Thermal properties of the mixed spin-1 and spin-3/2 Ising ferrimagnetic system with two different random single-ion anisotropies |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physica: A : theoretical and statistical physics |
Abbreviated Journal |
Physica A |
Volume |
500 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
500 |
Pages |
265-272 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In this work, we have performed Monte Carlo simulations to study a mixed spin-1 and spin-3/2 Ising ferrimagnetic system on a square lattice with two different random single-ion anisotropies. This lattice is divided in two interpenetrating sublattices with spins S-A = 1 in the sublattice A and S-B = 3/2 in the sublattice B. The exchange interaction between the spins on the sublattices is antiferromagnetic (J < 0). We used two random single-ion anisotropies, D-i(A) and D-j(B), on the sublattices A and B, respectively. We have determined the phase diagram of the model in the critical temperature T-c versus strength of the random single-ion anisotropy D plane and we shown that it exhibits only second-order phase transition lines. We also shown that this system displays compensation temperatures for some cases of the random single-ion distribution. (C) 2018 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
|
Language |
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Wos |
000430027400025 |
Publication Date |
2018-02-21 |
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 |
0378-4371 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.243 |
Times cited |
3 |
Open Access |
|
Notes |
; The authors acknowledge financial support by the Brazilian agencies CNPq, Brazil, CAPES, Brazil (Grant No. 88881.120851/2016-01) and FAPEMAT, Brazil. ; |
Approved |
Most recent IF: 2.243 |
Call Number |
UA @ lucian @ c:irua:150706UA @ admin @ c:irua:150706 |
Serial |
4985 |
Permanent link to this record |
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|
Author |
Eren, I.; Ozen, S.; Sozen, Y.; Yagmurcukardes, M.; Sahin, H. |
Title |
Vertical van der Waals heterostructure of single layer InSe and SiGe |
Type |
A1 Journal article |
Year |
2019 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
Volume |
123 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
51 |
Pages |
31232-31237 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
Abstract |
We present a first-principles investigation on the stability, electronic structure, and mechanical response of ultrathin heterostructures composed of single layers of InSe and SiGe. First, by performing total energy optimization and phonon calculations, we show that single layers of InSe and SiGe can form dynamically stable heterostructures in 12 different stacking types. Valence and conduction band edges of the heterobilayers form a type-I heterojunction having a tiny band gap ranging between 0.09 and 0.48 eV. Calculations on elastic-stiffness tensor reveal that two mechanically soft single layers form a heterostructure which is stiffer than the constituent layers because of relatively strong interlayer interaction. Moreover, phonon analysis shows that the bilayer heterostructure has highly Raman active modes at 205.3 and 43.7 cm(-1), stemming from the out-of-plane interlayer mode and layer breathing mode, respectively. Our results show that, as a stable type-I heterojunction, ultrathin heterobilayer of InSe/SiGe holds promise for nanoscale device applications. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000505632900050 |
Publication Date |
2019-12-03 |
Series Editor |
|
Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1932-7447; 1932-7455 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.536 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 4.536 |
Call Number |
UA @ admin @ c:irua:165718 |
Serial |
6332 |
Permanent link to this record |
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Author |
Bafekry, A.; Shojai, F.; Hoat, D.M.; Shahrokhi, M.; Ghergherehchi, M.; Nguyen, C. |
Title |
The mechanical, electronic, optical and thermoelectric properties of two-dimensional honeycomb-like of XSb (X = Si, Ge, Sn) monolayers: a first-principles calculations |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Rsc Advances |
Abbreviated Journal |
Rsc Adv |
Volume |
10 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
51 |
Pages |
30398-30405 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Herein, by using first-principles calculations, we demonstrate a two-dimensional (2D) of XSb (X = Si, Ge, and Sn) monolayers that have a honey-like crystal structure. The structural, mechanical, electronic, thermoelectric efficiency, and optical properties of XSb monolayers are studied.Ab initiomolecular dynamic simulations and phonon dispersion calculations suggests their good thermal and dynamical stabilities. The mechanical properties of XSb monolayers shows that the monolayers are considerably softer than graphene, and their in-plane stiffness decreases from SiSb to SnSb. Our results shows that the single layers of SiSb, GeSb and SnSb are semiconductor with band gap of 1.48, 0.77 and 0.73 eV, respectively. The optical analysis illustrate that the first absorption peaks of the SiSb, GeSb and SnSb monolayers along the in-plane polarization are located in visible range of light which may serve as a promising candidate to design advanced optoelectronic devices. Thermoelectric properties of the XSb monolayers, including Seebeck coefficient, electrical conductivity, electronic thermal conductivity, power factor and figure of merit are calculated as a function of doping level at temperatures of 300 K and 800 K. Between the studied two-dimensional materials (2DM), SiSb single layer may be the most promising candidate for application in the thermoelectric generators. |
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 |
000561344000009 |
Publication Date |
2020-08-17 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2046-2069 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.9 |
Times cited |
2 |
Open Access |
|
Notes |
; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). ; |
Approved |
Most recent IF: 3.9; 2020 IF: 3.108 |
Call Number |
UA @ admin @ c:irua:172074 |
Serial |
6624 |
Permanent link to this record |
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Author |
Magnus, W.; Brosens, F. |
Title |
Occupation numbers in a quantum canonical ensemble : a projection operator approach |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Physica: A : theoretical and statistical physics |
Abbreviated Journal |
Physica A |
Volume |
518 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
518 |
Pages |
253-264 |
Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) |
Abstract |
Recently, we have used a projection operator to fix the number of particles in a second quantization approach in order to deal with the canonical ensemble. Having been applied earlier to handle various problems in nuclear physics that involve fixed particle numbers, the projector formalism was extended to grant access as well to quantum-statistical averages in condensed matter physics, such as particle densities and correlation functions. In this light, the occupation numbers of the subsequent single-particle energy eigenstates are key quantities to be examined. The goal of this paper is (1) to provide a sound extension of the projector formalism directly addressing the occupation numbers as well as the chemical potential, and (2) to demonstrate how the emerging problems related to numerical instability for fermions can be resolved to obtain the canonical statistical quantities for both fermions and bosons. (C) 2018 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000456359200021 |
Publication Date |
2018-11-28 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0378-4371 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.243 |
Times cited |
1 |
Open Access |
|
Notes |
; ; |
Approved |
Most recent IF: 2.243 |
Call Number |
UA @ admin @ c:irua:157468 |
Serial |
5223 |
Permanent link to this record |
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Author |
Bafekry, A.; Ghergherehchi, M.; Shayesteh, S.F.; Peeters, F.M. |
Title |
Adsorption of molecules on C3N nanosheet : a first-principles calculations |
Type |
A1 Journal article |
Year |
2019 |
Publication |
Chemical physics |
Abbreviated Journal |
Chem Phys |
Volume |
526 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
526 |
Pages |
110442 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using first-principles calculations we investigate the interaction of various molecules, including H-2, N-2, CO, CO2, H2O, H2S, NH3, CH4 with a C3N nanosheet. Due to the weaker interaction between H-2, N-2, CO, CO2, H2O, H2S, NH3, and CH4 molecules with C3N, the adsorption energy is small and does not yield any significant distortion of the C3N lattice and the molecules are physisorbed. Calculated charge transfer shows that these molecules act as weak donors. However, adsorption of O-2, NO, NO2 and SO2 molecules are chemisorbed, they receive electrons from C3N and act as a strong acceptor. They interact strongly through hybridizing its frontier orbitals with the p-orbital of C3N, modifying the electronic structure of C3N. Our theoretical studies indicate that C3N-based sensor has a high potential for O-2, NO, NO2 and SO2 molecules detection. |
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 |
000481606000006 |
Publication Date |
2019-07-09 |
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 |
0301-0104 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.767 |
Times cited |
46 |
Open Access |
|
Notes |
; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). In addition, this work was supported by the FLAG-ERA project 2DTRANS and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 1.767 |
Call Number |
UA @ admin @ c:irua:161779 |
Serial |
5405 |
Permanent link to this record |
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Author |
Bafekry, A.; Shojaei, F.; Obeid, M.M.; Ghergherehchi, M.; Nguyen, C.; Oskouian, M. |
Title |
Two-dimensional silicon bismotide (SiBi) monolayer with a honeycomb-like lattice: first-principles study of tuning the electronic properties |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Rsc Advances |
Abbreviated Journal |
Rsc Adv |
Volume |
10 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
53 |
Pages |
31894-31900 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using density functional theory, we investigate a novel two-dimensional silicon bismotide (SiBi) that has a layered GaSe-like crystal structure.Ab initiomolecular dynamic simulations and phonon dispersion calculations suggest its good thermal and dynamical stability. The SiBi monolayer is a semiconductor with a narrow indirect bandgap of 0.4 eV. Our results show that the indirect bandgap decreases as the number of layers increases, and when the number of layers is more than six layers, direct-to-indirect bandgap switching occurs. The SiBi bilayer is found to be very sensitive to an E-field. The bandgap monotonically decreases in response to uniaxial and biaxial compressive strain, and reaches 0.2 eV at 5%, while at 6%, the semiconductor becomes a metal. For both uniaxial and biaxial tensile strains, the material remains a semiconductor and indirect-to-direct bandgap transition occurs at a strain of 3%. Compared to a SiBi monolayer with a layer thickness of 4.89 angstrom, the bandgap decreases with either increasing or decreasing layer thickness, and at a thicknesses of 4.59 to 5.01 angstrom, the semiconductor-to-metal transition happens. In addition, under pressure, the semiconducting character of the SiBi bilayer with a 0.25 eV direct bandgap is preserved. Our results demonstrate that the SiBi nanosheet is a promising candidate for designing high-speed low-dissipation devices. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000565206400027 |
Publication Date |
2020-09-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
2046-2069 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.9 |
Times cited |
8 |
Open Access |
|
Notes |
; This work was supported by the National Research Foundation of Korea (NRF) grant, funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). ; |
Approved |
Most recent IF: 3.9; 2020 IF: 3.108 |
Call Number |
UA @ admin @ c:irua:172045 |
Serial |
6644 |
Permanent link to this record |
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Author |
Fernández Becerra, V.; Milošević, M.V. |
Title |
Dynamics of skyrmions and edge states in the resistive regime of mesoscopic p-wave superconductors |
Type |
A1 Journal article |
Year |
2017 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
Volume |
533 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
533 |
Pages |
91-95 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In a mesoscopic sample of a chiral p-wave superconductor, novel states comprising skyrmions and edge states have been stabilized in out-of-plane applied magnetic field. Using the time-dependent Ginzburg-Landau equations we shed light on the dynamic response of such states to an external applied current. Three different regimes are obtained, namely, the superconducting (stationary), resistive (non-stationary) and normal regime, similarly to conventional s-wave superconductors. However, in the resistive regime and depending on the external current, we found that moving skyrmions and the edge state behave distinctly different from the conventional kinematic vortex, thereby providing new fingerprints for identification of p-wave superconductivity. (C) 2016 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000395954100014 |
Publication Date |
2016-07-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4534 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.404 |
Times cited |
3 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 1.404 |
Call Number |
UA @ lucian @ c:irua:142534 |
Serial |
4592 |
Permanent link to this record |
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|
Author |
Vodolazov, D.Y.; Berdiyorov, G.; Peeters, F.M. |
Title |
Negative magnetoresistance in thin superconducting films with parallel orientation of current and magnetic field |
Type |
A1 Journal article |
Year |
2018 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
Volume |
552 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
552 |
Pages |
64-66 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Thin superconducting films can exhibit negative magnetoresistance when an in-plane external magnetic field is aligned parallel with the transport current. We explain this effect as due to appearance of parallel vortices in the plain of the film at the first critical magnetic field H-c1 which leads to an enhancement of the superconducting properties and impedes the motion of the current induced perpendicular vortices. Our theoretical results are based on a numerical solution of the time-dependent and stationary 3D Ginzburg-Landau equations. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
Language |
|
Wos |
000440786600012 |
Publication Date |
2018-07-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0921-4534 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.404 |
Times cited |
6 |
Open Access |
|
Notes |
; The work is supported by the Russian Science Foundation Project No. 17-72-30036 and the Malthusian programme of the Flemish government. ; |
Approved |
Most recent IF: 1.404 |
Call Number |
UA @ lucian @ c:irua:153067UA @ admin @ c:irua:153067 |
Serial |
5117 |
Permanent link to this record |
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|
|
Author |
Oueslati, S.; Brammertz, G.; Buffiere, M.; ElAnzeery, H.; Touayar, O.; Koeble, C.; Bekaert, J.; Meuris, M.; Poortmans, J. |
Title |
Physical and electrical characterization of high-performance Cu2ZnSnSe4 based thin film solar cells |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Thin solid films : an international journal on the science and technology of thin and thick films |
Abbreviated Journal |
Thin Solid Films |
Volume |
582 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
582 |
Pages |
224-228 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We report on the electrical, optical and physical properties of Cu2ZnSnSe4 solar cells using an absorber layer fabricated by selenization of sputtered Cu, Zn and Cu10Sn90 multilayers. A maximum active-area conversion efficiency of 10.4% under AM1.5G was measured with a maximum short circuit current density of 39.7 mA/cm(2), an open circuit voltage of 394 mV and a fill factor of 66.4%. We perform electrical and optical characterization using photoluminescence spectroscopy, external quantum efficiency, current-voltage and admittance versus temperature measurements in order to derive information about possible causes for the low open circuit voltage values observed. The main defects derived from these measurements are strong potential fluctuations in the absorber layer as well as a potential barrier of the order of 133 meV at the back side contact. (C) 2014 Elsevier B.V. All rights reserved. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Lausanne |
Editor |
|
Language |
|
Wos |
000352225900048 |
Publication Date |
2014-10-20 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0040-6090 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
1.879 |
Times cited |
49 |
Open Access |
|
Notes |
; We would like to acknowledge Tom De Geyter, Greetje Godiers, and Guido Huyberechts from Flamac in Gent for sputtering of the metal layers. AGC is acknowledged for providing substrates. This research is partially funded by the Flemish government, Department Economy, Science and Innovation. ; |
Approved |
Most recent IF: 1.879; 2015 IF: 1.759 |
Call Number |
UA @ lucian @ c:irua:132504 |
Serial |
4225 |
Permanent link to this record |
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|
|
Author |
Ramos, I.R.O.; Ferreira, W.P.; Munarin, F.F.; Farias, G.A.; Peeters, F.M. |
Title |
Bilayer crystals of charged magnetic dipoles : structure and phonon spectrum |
Type |
A1 Journal article |
Year |
2012 |
Publication |
Physical review : E : statistical, nonlinear, and soft matter physics |
Abbreviated Journal |
Phys Rev E |
Volume |
85 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
5:1 |
Pages |
051404-051404,12 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We study the structure and phonon spectrum of a two-dimensional bilayer system of classical charged dipoles oriented perpendicular to the plane of the layers for equal density in each layer. This system can be tuned through six different crystalline phases by changing the interlayer separation or the charge and/or dipole moment of the particle. The presence of the charge on the dipole particles is responsible for the nucleation of five staggered phases and a disordered phase which are not found in the magnetic dipole bilayer system. These extra phases are a consequence of the competition between the repulsive Coulomb and the attractive dipole interlayer interaction. We present the phase diagram and determine the order of the phase transitions. The phonon spectrum of the system was calculated within the harmonic approximation, and a nonmonotonic behavior of the phonon spectrum is found as a function of the effective strength of the interparticle interaction. The stability of the different phases is determined. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
Woodbury (NY) |
Editor |
|
Language |
|
Wos |
000304403400002 |
Publication Date |
2012-05-30 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.366 |
Times cited |
8 |
Open Access |
|
Notes |
; This work was supported by the Brazilian agencies CNPq, CAPES, and FUNCAP (PRONEX grant), the Flemish Science Foundation (FWO-Vl), the bilateral program between Flanders and Brazil, and the CNPq-FWO collaborating project. The authors are grateful to Prof. G. Goldoni for some technical clarifications concerning Ref. [18]. ; |
Approved |
Most recent IF: 2.366; 2012 IF: 2.313 |
Call Number |
UA @ lucian @ c:irua:98940 |
Serial |
233 |
Permanent link to this record |
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|
|
Author |
Apolinario, S.W.S.; Aguiar, J.A.; Peeters, F.M. |
Title |
Angular melting scenarios in binary dusty-plasma Coulomb balls : magic versus normal clusters |
Type |
A1 Journal article |
Year |
2014 |
Publication |
Physical review : E : statistical, nonlinear, and soft matter physics |
Abbreviated Journal |
Phys Rev E |
Volume |
90 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
6 |
Pages |
063113 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Molecular-dynamic simulations were performed in order to investigate the melting processes of isotropically confined binary systems. We considered two species of particles, which differ by their amount of electric charge. A Lindemann type of criterion was used to determine the angular melting temperature. We demonstrate that the magic-to-normal cluster transition can evolve in two distinct ways, that is, through a structural phase transition of the first order or via a smooth transition where an increase of the shells' width leads to a continuous decreasing mechanical stability of the system. Moreover, for large systems, we demonstrate that the internal cluster exerts a minor effect on the mechanical stability of the external shell. Furthermore, we show that highly symmetric configurations, such as those found for multiple ring structures, have large mechanical stability, i.e., high angular melting temperature. |
Address |
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Corporate Author |
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Thesis |
|
Publisher |
American Institute of Physics |
Place of Publication |
Woodbury (NY) |
Editor |
|
Language |
|
Wos |
000347207000027 |
Publication Date |
2014-12-29 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.366 |
Times cited |
1 |
Open Access |
|
Notes |
; This work was supported by FACEPE (Fundacao de Amparo a Ciencia e Tecnologia do Estado de Pernambuco) Grant No. APQ-1800-1.05/ 12, the bilatera project between CNPq and FWO-VL, and the Flemish Science Foundation (FWO-Vl). ; |
Approved |
Most recent IF: 2.366; 2014 IF: 2.288 |
Call Number |
UA @ lucian @ c:irua:122828 |
Serial |
116 |
Permanent link to this record |
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|
Author |
Xu, B.; Milošević, M.V.; Peeters, F.M. |
Title |
Calorimetric properties of mesoscopic superconducting disks, rings, and cylinders |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
81 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
6 |
Pages |
064501,1-064501,10 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The thermal signatures of superconductivity in mesoscopic disks, rings and cylinders are calculated within the Ginzburg-Landau theory. In an applied perpendicular magnetic field H the heat capacity of mesoscopic samples shows a strong dependence on the realized vortex state; discontinuities are found at the critical field for different vorticities, as well as at the superconducting-to-normal state transition. The same applies to the intermediate state of type-I superconductors. Even the subtle changes in the fluxoid distribution inside the sample leave clear signatures on heat capacity, which is particularly useful for fully three-dimensional samples whose interior is often inaccessible by magnetometry. The heat-capacity jump ΔC(H) at the critical temperature exhibits quasiperiodic modulations as a function of magnetic field. In mesoscopic superconducting rings, these oscillations provide calorimetric verification of the Little-Parks effect. |
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 |
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Language |
|
Wos |
000274998100091 |
Publication Date |
2010-02-01 |
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 |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
17 |
Open Access |
|
Notes |
; We are grateful to O. Bourgeois for useful discussions. This work was supported by the Flemish Science Foundation (FWO-VI), the Interuniversity Attraction Poles (IAP) Program-Belgian State-Belgian Science Policy, ESF-JSPS NES program and the ESF-AQDJJ network. ; |
Approved |
Most recent IF: 3.836; 2010 IF: 3.774 |
Call Number |
UA @ lucian @ c:irua:81766 |
Serial |
271 |
Permanent link to this record |
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Author |
Saniz, R.; Partoens, B.; Peeters, F.M. |
Title |
Confinement effects on electron and phonon degrees of freedom in nanofilm superconductors : a Green function approach |
Type |
A1 Journal article |
Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
87 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
6 |
Pages |
064510-64513 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The Green function approach to the Bardeen-Cooper-Schrieffer theory of superconductivity is used to study nanofilms. We go beyond previous models and include effects of confinement on the strength of the electron-phonon coupling as well as on the electronic spectrum and on the phonon modes. Within our approach, we find that in ultrathin films, confinement effects on the electronic screening become very important. Indeed, contrary to what has been advanced in recent years, the sudden increases of the density of states when new bands start to be occupied as the film thickness increases, tend to suppress the critical temperature rather than to enhance it. On the other hand, the increase of the number of phonon modes with increasing number of monolayers in the film leads to an increase in the critical temperature. As a consequence, the superconducting critical parameters in such nanofilms are determined by these two competing effects. Furthermore, in sufficiently thin films, the condensate consists of well-defined subcondensates associated with the occupied bands, each with a distinct coherence length. The subcondensates can interfere constructively or destructively giving rise to an interference pattern in the Cooper pair probability density. |
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 |
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Language |
|
Wos |
000315374100009 |
Publication Date |
2013-02-25 |
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 |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
6 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl). R.S. thanks M. R. Norman, B. Soree, and L. Komendova for useful comments. ; |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
Call Number |
UA @ lucian @ c:irua:107072 |
Serial |
487 |
Permanent link to this record |
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Author |
Komendová, L.; Milošević, M.V.; Shanenko, A.A.; Peeters, F.M. |
Title |
Different length scales for order parameters in two-gap superconductors : extended Ginzburg-Landau theory |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
Volume |
84 |
Issue ![sorted by Issue field, ascending order (up)](img/sort_asc.gif) |
6 |
Pages |
064522-064522,5 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using the Ginzburg-Landau theory extended to the next-to-leading order, we determine numerically the healing lengths of the two order parameters at the two-gap superconductor/normal metal interface. We demonstrate on several examples that those can be different even in the strict domain of applicability of the Ginzburg-Landau theory. This justifies the use of this theory to describe relevant physics of two-gap superconductors, distinguishing them from their single-gap counterparts. The calculational degree of complexity increases only slightly with respect to the conventional Ginzburg-Landau expansion, thus the extended Ginzburg-Landau model remains numerically far less demanding compared to the full microscopic approaches. |
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 |
000294226000013 |
Publication Date |
2011-08-25 |
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 |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.836 |
Times cited |
56 |
Open Access |
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-INSTANS network. ; |
Approved |
Most recent IF: 3.836; 2011 IF: 3.691 |
Call Number |
UA @ lucian @ c:irua:92414 |
Serial |
695 |
Permanent link to this record |