|
Records |
Links |
|
Author |
da Costa, D.R.; Zarenia, M.; Chaves, A.; Farias, G.A.; Peeters, F.M. |
|
|
Title |
Magnetic field dependence of energy levels in biased bilayer graphene quantum dots |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
|
|
Volume |
93 |
Issue |
93 |
Pages |
085401 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
Using the tight-binding approach, we study the influence of a perpendicular magnetic field on the energy levels of hexagonal, triangular, and circular bilayer graphene (BLG) quantum dots (QDs) with zigzag and armchair edges. We obtain the energy levels for AB (Bernal)-stacked BLG QDs in both the absence and the presence of a perpendicular electric field (i.e., biased BLG QDs). We find different regions in the spectrum of biased QDs with respect to the crossing point between the lowest-electron and -hole Landau levels of a biased BLG sheet. Those different regions correspond to electron states that are localized at the center, edge, or corner of the BLG QD. Quantum Hall corner states are found to be absent in circular BLG QDs. The spatial symmetry of the carrier density distribution is related to the symmetry of the confinement potential, the position of zigzag edges, and the presence or absence of interlayer inversion symmetry. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000369402400008 |
Publication Date |
2016-02-01 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
22 |
Open Access |
|
|
|
Notes |
; This work was financially supported by CNPq, under Contract No. NanoBioEstruturas 555183/2005-0, PRONEX/FUNCAP, CAPES Foundation under the Process No. BEX 7178/13-1, the Flemish Science Foundation (FWO-Vl), the Bilateral programme between CNPq and FWO-Vl, and the Brazilian Program Science Without Borders (CsF). ; |
Approved |
Most recent IF: 3.836 |
|
|
Call Number |
c:irua:131623 |
Serial |
4038 |
|
Permanent link to this record |
|
|
|
|
Author |
Leenaerts, O.; Vercauteren, S.; Schoeters, B.; Partoens, B. |
|
|
Title |
System-size dependent band alignment in lateral two-dimensional heterostructures |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
2D materials |
Abbreviated Journal |
2D Mater |
|
|
Volume |
3 |
Issue |
3 |
Pages |
025012 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
The electronic band alignment in semiconductor heterostructures is a key factor for their use in electronic applications. The alignment problem has been intensively studied for bulk systems but is less well understood for low-dimensional heterostructures. In this work we investigate the alignment in two-dimensional lateral heterostructures. First-principles calculations are used to show that the electronic band offset depends crucially on the width and thickness of the heterostructure slab. The particular heterostructures under study consist of thin hydrogenated and fluorinated diamond slabs which are laterally joined together. Two different limits for the band offset are observed. For infinitely wide heterostructures the vacuum potential above the two materials is aligned leading to a large step potential within the heterostructure. For infinitely thick heterostructure slabs, on the other hand, there is no potential step in the heterostructure bulk, but a large potential step in the vacuum region above the heterojunction is observed. The band alignment in finite systems depends on the particular dimensions of the system. These observations are shown to result from an interface dipole at the heterojunction that tends to align the band structures. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000378571400032 |
Publication Date |
2016-04-13 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2053-1583 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
6.937 |
Times cited |
19 |
Open Access |
|
|
|
Notes |
This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government— department EWI. |
Approved |
Most recent IF: 6.937 |
|
|
Call Number |
c:irua:132792 c:irua:132792 |
Serial |
4055 |
|
Permanent link to this record |
|
|
|
|
Author |
Saqlain, M.A.; Hussain, A.; Siddiq, D.M.; Leenaerts, O.; Leitão, A.A. |
|
|
Title |
DFT Study of Synergistic Catalysis of the Water-Gas-Shift Reaction on Cu-Au Bimetallic Surfaces |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
ChemCatChem |
Abbreviated Journal |
Chemcatchem |
|
|
Volume |
8 |
Issue |
8 |
Pages |
1208-1217 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
The water-gas-shift reaction (WGSR) is an important industrial process that can be significantly enhanced at suitable catalyst surfaces. In this work, we investigate the catalytic behavior of metallic Cu(1 0 0) and bimetallic Cu–Au(1 0 0) surfaces. With density functional theory calculations, the variation in the Gibbs free energy (ΔG°), the activation barriers, and the rate constants for the WGSR are calculated. The variation in ΔG° for water dissociation shows that the process is spontaneous up to 520 K on the bimetallic surface and up to 229 K on the Cu(1 0 0) surface. The calculated rate constants for the process also show that the bimetallic surface is much more reactive than the Cu(1 0 0) surface. The calculated pressure–temperature phase diagram for water dissociation shows that the partial pressure of H2O required for water dissociation on the bimetallic surface is substantially lower than that on the Cu(1 0 0) surface at all the studied temperatures. Additionally, the calculations demonstrate that the kinetics of the water-gas-shift reaction is dominated by redox processes on both the surfaces. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000373074900026 |
Publication Date |
2016-02-26 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1867-3880 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.803 |
Times cited |
8 |
Open Access |
|
|
|
Notes |
; The authors would like to thank the Brazilian agencies CNPq, CAPES, FAPEMIG (CEX-PPM-00262/13), and TWAS for financial support and CENAPAD-SP for computational facilities. M.A. Saqlain pays special thanks to all the members of GFQSI for making his stay in Brazil memorable. ; |
Approved |
Most recent IF: 4.803 |
|
|
Call Number |
c:irua:133236 |
Serial |
4070 |
|
Permanent link to this record |
|
|
|
|
Author |
Govaerts, K.; Partoens, B.; Lamoen, D. |
|
|
Title |
Extended homologous series of Sn–O layered systems: A first-principles study |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Solid state communications |
Abbreviated Journal |
Solid State Commun |
|
|
Volume |
243 |
Issue |
243 |
Pages |
36-43 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
|
Abstract |
Apart from the most studied tin-oxide compounds, SnO and SnO2, intermediate states have been claimed to exist for more than a hundred years. In addition to the known homologous series (Seko et al., Phys. Rev. Lett. 100, 045702 (2008)), we here predict the existence of several new compounds with an O concentration between 50 % (SnO) and 67 % (SnO2). All these intermediate compounds are constructed from removing one or more (101) oxygen layers of SnO2. Since the van der Waals (vdW) interaction is known to be important for the Sn-Sn interlayer distances, we use a vdW-corrected functional, and compare these results with results obtained with PBE and hybrid functionals. We present the electronic properties of the intermediate structures and we observe a decrease of the band gap when (i) the O concentration increases and (ii) more SnO-like units are present for a given concentration. The contribution of the different atoms to the valence and conduction band is also investigated. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000381544200007 |
Publication Date |
2016-06-12 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0038-1098 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
1.554 |
Times cited |
10 |
Open Access |
|
|
|
Notes |
We gratefully acknowledge financial support from a GOA fund of the University of Antwerp. K.G. thanks the University of Antwerp for a PhD fellowship. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the Hercules Foundation and the Flemish Government – department EWI. |
Approved |
Most recent IF: 1.554 |
|
|
Call Number |
c:irua:134037 |
Serial |
4085 |
|
Permanent link to this record |
|
|
|
|
Author |
Mulkers, J.; Milošević, M.V.; Van Waeyenberge, B. |
|
|
Title |
Cycloidal versus skyrmionic states in mesoscopic chiral magnets |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
|
Volume |
93 |
Issue |
93 |
Pages |
214405 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
When subjected to the interfacially induced Dzyaloshinskii-Moriya interaction, the ground state in thin ferromagnetic films with high perpendicular anisotropy is cycloidal. The period of this cycloidal state depends on the strength of the Dzyaloshinskii-Moriya interaction. In this work, we have studied the effect of confinement on the magnetic ground state and excited states, and we determined the phase diagram of thin strips and thin square platelets by means of micromagnetic calculations. We show that multiple cycloidal states with different periods can be stable in laterally confined films, where the period of the cycloids does not depend solely on the Dzyaloshinskii-Moriya interaction strength but also on the dimensions of the film. The more complex states comprising skyrmions are also found to be stable, though with higher energy. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000377298600006 |
Publication Date |
2016-06-06 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2469-9950 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
28 |
Open Access |
|
|
|
Notes |
; ; |
Approved |
Most recent IF: 3.836 |
|
|
Call Number |
c:irua:133919 |
Serial |
4081 |
|
Permanent link to this record |
|
|
|
|
Author |
Nikolaev, A.V.; Lamoen, D.; Partoens, B. |
|
|
Title |
Extension of the basis set of linearized augmented plane wave (LAPW) method by using supplemented tight binding basis functions |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
The journal of chemical physics |
Abbreviated Journal |
J Chem Phys |
|
|
Volume |
145 |
Issue |
145 |
Pages |
014101 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
|
Abstract |
In order to increase the accuracy of the linearized augmented plane wave (LAPW) method, we present a new approach where the plane wave basis function is augmented by two different atomic radial components constructed at two different linearization energies corresponding to two different electron bands (or energy windows). We demonstrate that this case can be reduced to the standard treatment within the LAPW paradigm where the usual basis set is enriched by the basis functions of the tight binding type, which go to zero with zero derivative at the sphere boundary. We show that the task is closely related with the problem of extended core states which is currently solved by applying the LAPW method with local orbitals (LAPW+LO). In comparison with LAPW+LO, the number of supplemented basis functions in our approach is doubled, which opens up a new channel for the extension of the LAPW and LAPW+LO basis sets. The appearance of new supplemented basis functions absent in the LAPW+LO treatment is closely related with the existence of the ul-component in the canonical LAPW method. We discuss properties of additional tight binding basis functions and apply the extended basis set for computation of electron energy bands of lanthanum (face and body centered structures) and hexagonal close packed lattice of cadmium. We demonstrate that the new treatment gives lower total energies in comparison with both canonical LAPW and LAPW+LO, with the energy difference more pronounced for intermediate and poor LAPW basis sets. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000379584700003 |
Publication Date |
2016-07-05 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0021-9606 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.965 |
Times cited |
11 |
Open Access |
|
|
|
Notes |
A.V.N. acknowledges useful discussions with B. Verberck, E. V. Tkalya, and A. V. Bibikov. |
Approved |
Most recent IF: 2.965 |
|
|
Call Number |
c:irua:134290 |
Serial |
4099 |
|
Permanent link to this record |
|
|
|
|
Author |
Bercx, M.; Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D. |
|
|
Title |
First-principles analysis of the spectroscopic limited maximum efficiency of photovoltaic absorber layers for CuAu-like chalcogenides and silicon |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
|
|
Volume |
18 |
Issue |
18 |
Pages |
20542-20549 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
|
Abstract |
Chalcopyrite semiconductors are of considerable interest for application as absorber layers in thin-film photovoltaic cells. When growing films of these compounds, however, they are often found to contain CuAu-like domains, a metastable phase of chalcopyrite. It has been reported that for CuInS2, the presence of the CuAu-like phase improves the short circuit current of the chalcopyrite-based photovoltaic cell. We investigate the thermodynamic stability of both phases for a selected list of I-III-VI2 materials using a first-principles density functional theory approach. For the CuIn-VI2 compounds, the difference in formation energy between the chalcopyrite and CuAu-like phase is found to be close to 2 meV per atom, indicating a high likelihood of the presence of CuAu-like domains. Next, we calculate the spectroscopic limited maximum efficiency (SLME) of the CuAu-like phase and compare the results with those of the corresponding chalcopyrite phase. We identify several candidates with a high efficiency, such as CuAu-like CuInS2, for which we obtain an SLME of 29% at a thickness of 500 nm. We observe that the SLME can have values above the Shockley-Queisser (SQ) limit, and show that this can occur because the SQ limit assumes the absorptivity to be a step function, thus overestimating the radiative recombination in the detailed balance approach. This means that it is possible to find higher theoretical efficiencies within this framework simply by calculating the J-V characteristic with an absorption spectrum. Finally, we expand our SLME analysis to indirect band gap absorbers by studying silicon, and find that the SLME quickly overestimates the reverse saturation current of indirect band gap materials, drastically lowering their calculated efficiency. |
|
|
Address |
EMAT & CMT groups, Department of Physics, University of Antwerp, Campus Groenenborger, Groenenborgerlaan 171, 2020 Antwerp, Belgium. marnik.bercx@uantwerpen.be |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Wos |
000381428600058 |
Publication Date |
2016-07-08 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1463-9076 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.123 |
Times cited |
34 |
Open Access |
|
|
|
Notes |
We acknowledge financial support of FWO-Vlaanderen through projects G.0150.13N and G.0216.14N and ERA-NET RUS Plus/FWO, Grant G0D6515N. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO FWOVlaanderen. |
Approved |
Most recent IF: 4.123 |
|
|
Call Number |
c:irua:135091 |
Serial |
4112 |
|
Permanent link to this record |
|
|
|
|
Author |
Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D. |
|
|
Title |
First-principles study of the optoelectronic properties and photovoltaic absorber layer efficiency of Cu-based chalcogenides |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
|
|
Volume |
120 |
Issue |
120 |
Pages |
085707 |
|
|
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
|
|
Abstract |
Cu-based chalcogenides are promising materials for thin-film solar cells with more than 20% measured
cell efficiency. Using first-principles calculations based on density functional theory, the
optoelectronic properties of a group of Cu-based chalcogenides Cu2-II-IV-VI4 is studied. They are
then screened with the aim of identifying potential absorber materials for photovoltaic applications.
The spectroscopic limited maximum efficiency (SLME) introduced by Yu and Zunger [Phys. Rev.
Lett. 108, 068701 (2012)] is used as a metric for the screening. After constructing the currentvoltage
curve, the SLME is calculated from the maximum power output. The role of the nature of
the band gap, direct or indirect, and also of the absorptivity of the studied materials on the maximum
theoretical power conversion efficiency is studied. Our results show that Cu2II-GeSe4 with
II¼ Cd and Hg, and Cu2-II-SnS4 with II ¼ Cd, Hg, and Zn have a higher theoretical efficiency
compared with the materials currently used as absorber layer. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000383913400074 |
Publication Date |
2016-08-30 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0021-8979 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.068 |
Times cited |
29 |
Open Access |
|
|
|
Notes |
We acknowledge the financial support from the FWO-Vlaanderen through project G.0150.13N and a GOA fund from the University of Antwerp. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), bothfunded by the FWO-Vlaanderen and the Flemish Government–department EWI. |
Approved |
Most recent IF: 2.068 |
|
|
Call Number |
c:irua:135089 |
Serial |
4113 |
|
Permanent link to this record |
|
|
|
|
Author |
Pant, A.; Torun, E.; Chen, B.; Bhat, S.; Fan, X.; Wu, K.; Wright, D.P.; Peeters, F.M.; Soignard, E.; Sahin, H.; Tongay, S. |
|
|
Title |
Strong dichroic emission in the pseudo one dimensional material ZrS3 |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Nanoscale |
Abbreviated Journal |
Nanoscale |
|
|
Volume |
8 |
Issue |
8 |
Pages |
16259-16265 |
|
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
|
|
Abstract |
Zirconium trisulphide (ZrS3), a member of the layered transition metal trichalcogenides (TMTCs) family, has been studied by angle-resolved photoluminescence spectroscopy (ARPLS). The synthesized ZrS3 layers possess a pseudo one-dimensional nature where each layer consists of ZrS3 chains extending along the b-lattice direction. Our results show that the optical properties of few-layered ZrS3 are highly anisotropic as evidenced by large PL intensity variation with the polarization direction. Light is efficiently absorbed when the E-field is polarized along the chain (b-axis), but the field is greatly attenuated and absorption is reduced when it is polarized vertical to the 1D-like chains as the wavelength of the exciting light is much longer than the width of each 1D chain. The observed PL variation with polarization is similar to that of conventional 1D materials, i.e., nanowires, and nanotubes, except for the fact that here the 1D chains interact with each other giving rise to a unique linear dichroism response that falls between the 2D (planar) and 1D (chain) limit. These results not only mark the very first demonstration of PL polarization anisotropy in 2D systems, but also provide novel insight into how the interaction between adjacent 1D-like chains and the 2D nature of each layer influences the overall optical anisotropy of pseudo-1D materials. Results are anticipated to have an impact on optical technologies such as polarized detectors, near-field imaging, communication systems, and bio-applications relying on the generation and detection of polarized light. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000384531600018 |
Publication Date |
2016-08-09 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2040-3364 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
7.367 |
Times cited |
54 |
Open Access |
|
|
|
Notes |
; S. Tongay gratefully acknowledges support from NSF DMR-1552220. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). HS is supported by a FWO postdoctoral fellowship. ; |
Approved |
Most recent IF: 7.367 |
|
|
Call Number |
UA @ lucian @ c:irua:144656 |
Serial |
4116 |
|
Permanent link to this record |
|
|
|
|
Author |
Aierken, Y.; Leenaerts, O.; Peeters, F.M. |
|
|
Title |
A first-principles study of stable few-layer penta-silicene |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Physical chemistry, chemical physics |
Abbreviated Journal |
Phys Chem Chem Phys |
|
|
Volume |
18 |
Issue |
18 |
Pages |
18486-18492 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
Recently penta-graphene was proposed as a stable two-dimensional carbon allotrope consisting of a single layer of interconnected carbon pentagons [Zhang et al., PNAS, 2015, 112, 2372]. Its silicon counterpart, penta-silicene, however, is not stable. In this work, we show that multilayers of penta-silicene form stable materials with semiconducting or metallic properties, depending on the stacking mode. We demonstrate their dynamic stability through their phonon spectrum and using molecular dynamics. A particular type of bilayer penta-silicene is found to have lower energy than all of the known hexagonal silicene bilayers and forms therefore the most stable bilayer silicon material predicted so far. The electronic and mechanical properties of these new silicon allotropes are studied in detail and their behavior under strain is investigated. We demonstrate that strain can be used to tune its band gap. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Cambridge |
Editor |
|
|
|
Language |
|
Wos |
000379486200077 |
Publication Date |
2016-06-15 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1463-9076 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.123 |
Times cited |
42 |
Open Access |
|
|
|
Notes |
; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO-Vl). The computational resources used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government-department EWI. ; |
Approved |
Most recent IF: 4.123 |
|
|
Call Number |
UA @ lucian @ c:irua:134942 |
Serial |
4132 |
|
Permanent link to this record |
|
|
|
|
Author |
Guidini, A.; Flammia, L.; Milošević, M.V.; Perali, A. |
|
|
Title |
BCS-BEC crossover in quantum confined superconductors |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Journal of superconductivity and novel magnetism |
Abbreviated Journal |
J Supercond Nov Magn |
|
|
Volume |
29 |
Issue |
29 |
Pages |
711-715 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
Ultranarrow superconductors are in the strong quantum confinement regime with formation of multiple coherent condensates associated with the many subbands of the electronic structure. Here, we analyze the multiband BCS-BEC crossover induced by the chemical potential tuned close to a subband bottom, in correspondence of a superconducting shape resonance. The evolution of the condensate fraction and of the pair correlation length in the ground state as functions of the chemical potential demonstrates the tunability of the BCS-BEC crossover for the condensate component of the selected subband. The extension of the crossover regime increases when the pairing strength and/or the characteristic energy of the interaction get larger. Our results indicate the coexistence of large and small Cooper pairs in the crossover regime, leading to the optimal parameter configuration for high transition temperature superconductivity. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
|
|
Language |
|
Wos |
000371089500034 |
Publication Date |
2015-12-23 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1557-1939 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
1.18 |
Times cited |
12 |
Open Access |
|
|
|
Notes |
; We acknowledge A. Bianconi and A.A. Shanenko for useful discussions. A.P. acknowledges financial support from the University of Camerino under the project FAR “Control and enhancement of superconductivity by engineering materials at the nanoscale”. M.V.M. acknowledges support from the Research Foundation – Flanders (FWO) and the Special Research Funds of the University of Antwerp (BOF-UA). A.P. and M.V.M. acknowledge the collaboration within the MultiSuper International Network (http://www.multisuper.org) for exchange of ideas and suggestions. ; |
Approved |
Most recent IF: 1.18 |
|
|
Call Number |
UA @ lucian @ c:irua:132287 |
Serial |
4143 |
|
Permanent link to this record |
|
|
|
|
Author |
Bacaksiz, C.; Cahangirov, S.; Rubio, A.; Senger, R.T.; Peeters, F.M.; Sahin, H. |
|
|
Title |
Bilayer SnS2 : tunable stacking sequence by charging and loading pressure |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
|
|
Volume |
93 |
Issue |
93 |
Pages |
125403 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
Employing density functional theory-based methods, we investigate monolayer and bilayer structures of hexagonal SnS2, which is a recently synthesized monolayer metal dichalcogenide. Comparison of the 1H and 1T phases of monolayer SnS2 confirms the ground state to be the 1T phase. In its bilayer structure we examine different stacking configurations of the two layers. It is found that the interlayer coupling in bilayer SnS2 is weaker than that of typical transition-metal dichalcogenides so that alternative stacking orders have similar structural parameters and they are separated with low energy barriers. A possible signature of the stacking order in the SnS2 bilayer has been sought in the calculated absorbance and reflectivity spectra. We also study the effects of the external electric field, charging, and loading pressure on the characteristic properties of bilayer SnS2. It is found that (i) the electric field increases the coupling between the layers at its preferred stacking order, so the barrier height increases, (ii) the bang gap value can be tuned by the external E field and under sufficient E field, the bilayer SnS2 can become a semimetal, (iii) the most favorable stacking order can be switched by charging, and (iv) a loading pressure exceeding 3 GPa changes the stacking order. The E-field tunable band gap and easily tunable stacking sequence of SnS2 layers make this 2D crystal structure a good candidate for field effect transistor and nanoscale lubricant applications. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000371405000005 |
Publication Date |
2016-03-03 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
38 |
Open Access |
|
|
|
Notes |
; The calculations were performed at TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). C.B., H.S., and R.T.S. acknowledge support from TUBITAK Project No. 114F397. H.S. is supported by an FWO Pegasus Marie Curie Fellowship. S.C. and A.R. acknowledge financial support from the Marie Curie grant FP7-PEOPLE-2013-IEF Project No. 628876, the European Research Council (ERC-2010-AdG-267374), and Spanish grant Grupos Consolidados (IT578-13). S.C. acknowledges support from the Scientific and Technological Research Council of Turkey (TUBITAK) under Project No. 115F388. ; |
Approved |
Most recent IF: 3.836 |
|
|
Call Number |
UA @ lucian @ c:irua:132345 |
Serial |
4144 |
|
Permanent link to this record |
|
|
|
|
Author |
Hawrylak, P.; Peeters, F.; Ensslin, K. |
|
|
Title |
Carbononics : integrating electronics, photonics and spintronics with graphene quantum dots Preface |
Type |
Editorial |
|
Year |
2016 |
Publication |
Physica status solidi: rapid research letters |
Abbreviated Journal |
Phys Status Solidi-R |
|
|
Volume |
10 |
Issue |
10 |
Pages |
11-12 |
|
|
Keywords |
Editorial; Condensed Matter Theory (CMT) |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Wiley-v c h verlag gmbh |
Place of Publication |
Weinheim |
Editor |
|
|
|
Language |
|
Wos |
000368814500002 |
Publication Date |
2016-01-20 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1862-6254 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.032 |
Times cited |
7 |
Open Access |
|
|
|
Notes |
; ; |
Approved |
Most recent IF: 3.032 |
|
|
Call Number |
UA @ lucian @ c:irua:131600 |
Serial |
4146 |
|
Permanent link to this record |
|
|
|
|
Author |
Van der Donck, M.; Peeters, F.M.; Van Duppen, B. |
|
|
Title |
Comment on “Creating in-plane pseudomagnetic fields in excess of 1000 T by misoriented stacking in a graphene bilayer” |
Type |
Editorial |
|
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
|
|
Volume |
93 |
Issue |
93 |
Pages |
247401 |
|
|
Keywords |
Editorial; Condensed Matter Theory (CMT) |
|
|
Abstract |
In a recent paper [Phys. Rev. B 89, 125418 (2014)], the authors argue that it is possible to map the electronic properties of twisted bilayer graphene to those of bilayer graphene in an in-plane magnetic field. However, their description of the low-energy dynamics of twisted bilayer graphene is restricted to the extended zone scheme and therefore neglects the effects of the superperiodic structure. If the energy spectrum is studied in the supercell Brillouin zone, we find that the comparison with an in-plane magnetic field fails because (i) the energy spectra of the two situations exhibit different symmetries and (ii) the low-energy spectra are very different. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Amer physical soc |
Place of Publication |
College pk |
Editor |
|
|
|
Language |
|
Wos |
000377802200009 |
Publication Date |
2016-06-14 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
6 |
Open Access |
|
|
|
Notes |
; ; |
Approved |
Most recent IF: 3.836 |
|
|
Call Number |
UA @ lucian @ c:irua:134601 |
Serial |
4151 |
|
Permanent link to this record |
|
|
|
|
Author |
Agarwal, T.; Sorée, B.; Radu, I.; Raghavan, P.; Fiori, G.; Iannaccone, G.; Thean, A.; Heyns, M.; Dehaene, W. |
|
|
Title |
Comparison of short-channel effects in monolayer MoS2 based junctionless and inversion-mode field-effect transistors |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
|
|
Volume |
108 |
Issue |
108 |
Pages |
023506 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
Conventional junctionless (JL) multi/gate (MuG) field-effect transistors (FETs) require extremely scaled channels to deliver high on-state current with low short-channel effect related leakage. In this letter, using ultra-thin 2D materials (e.g., monolayer MoS2), we present comparison of short-channel effects in JL, and inversion-mode (IM) FETs. We show that JL FETs exhibit better sub-threshold slope (S.S.) and drain-induced-barrier-lowering (DIBL) in comparison to IM FETs due to reduced peak electric field at the junctions. But, threshold voltage (VT) roll-off with channel length downscaling is found to be significantly higher in JL FETs than IM FETs, due to higher source/drain controlled charges (dE/dx) in the channel. Further, we show that although VT roll-off in JL FETs improves by increasing the gate control, i.e., by scaling the oxide, or channel thickness, the sensitivity of threshold voltage on structural parameters is found out to be high. (C) 2016 AIP Publishing LLC. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
|
|
Language |
|
Wos |
000370258400056 |
Publication Date |
2016-01-16 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0003-6951; 1077-3118 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.411 |
Times cited |
13 |
Open Access |
|
|
|
Notes |
; ; |
Approved |
Most recent IF: 3.411 |
|
|
Call Number |
UA @ lucian @ c:irua:132318 |
Serial |
4152 |
|
Permanent link to this record |
|
|
|
|
Author |
Sahin, H.; Torun, E.; Bacaksiz, C.; Horzum, S.; Kang, J.; Senger, R.T.; Peeters, F.M. |
|
|
Title |
Computing optical properties of ultra-thin crystals |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Wiley Interdisciplinary Reviews: Computational Molecular Science |
Abbreviated Journal |
Wires Comput Mol Sci |
|
|
Volume |
6 |
Issue |
6 |
Pages |
351-368 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
An overview is given of recent advances in experimental and theoretical understanding of optical properties of ultra-thin crystal structures (graphene, phosphorene, silicene, MoS2 , MoSe2, WS2, WSe2, h-AlN, h-BN, fluorographene, and graphane). Ultra-thin crystals are atomically thick-layered crystals that have unique properties which differ from their 3D counterpart. Because of the difficulties in the synthesis of few-atom-thick crystal structures, which are thought to be the main building blocks of future nanotechnology, reliable theoretical predictions of their electronic, vibrational, and optical properties are of great importance. Recent studies revealed the reliable predictive power of existing theoretical approaches based on density functional theory. (C) 2016 John Wiley & Sons, Ltd WIREs Comput Mol Sci 2016, 6:351-368. doi: 10.1002/wcms.1252 For further resources related to this article, please visit the . |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000379267300002 |
Publication Date |
2016-02-20 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1759-0876 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
14.016 |
Times cited |
14 |
Open Access |
|
|
|
Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). H.S. is supported by a FWO Pegasus Long Marie Curie Fellowship. J.K. is supported by a FWO Pegasus short Marie Curie Fellowship. ; |
Approved |
Most recent IF: 14.016 |
|
|
Call Number |
UA @ lucian @ c:irua:134649 |
Serial |
4155 |
|
Permanent link to this record |
|
|
|
|
Author |
Yang, S.; Kang, J.; Yue, Q.; Coey, J.M.D.; Jiang, C. |
|
|
Title |
Defect-modulated transistors and gas-enhanced photodetectors on ReS2 nanosheets |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Advanced Materials Interfaces |
Abbreviated Journal |
Adv Mater Interfaces |
|
|
Volume |
3 |
Issue |
3 |
Pages |
1500707 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000373149400011 |
Publication Date |
2016-01-18 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2196-7350; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.279 |
Times cited |
22 |
Open Access |
|
|
|
Notes |
; This work was supported by the National Natural Science Foundations of China (NSFC) under Grant No.51331001. The authors thank S. Tongay for giving them the ReS<INF>2</INF> crystals. ; |
Approved |
Most recent IF: 4.279 |
|
|
Call Number |
UA @ lucian @ c:irua:133232 |
Serial |
4159 |
|
Permanent link to this record |
|
|
|
|
Author |
Berdiyorov, G.R.; Madjet, M.E.; El-Mellouhi, F.; Peeters, F.M. |
|
|
Title |
Effect of crystal structure on the electronic transport properties of the organometallic perovskite CH3NH3PbI3 |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Solar energy materials and solar cells
T2 – 2nd International Renewable and Sustainable Energy Conference (IRSEC), OCT 17-19, 2014, Ouarzazate, MOROCCO |
Abbreviated Journal |
Sol Energ Mat Sol C |
|
|
Volume |
148 |
Issue |
148 |
Pages |
60-66 |
|
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
|
|
Abstract |
Using density-functional theory in combination with the nonequilibrium Green's function formalism, we study the effect of the crystal lattice structure of organometallic perovskite CH3NH3PbI3 on its electronic transport properties. Both dispersive interactions and spin-orbit coupling are taken into account in describing structural and electronic properties of the system. We consider two different phases of the material, namely the orthorhombic and cubic lattice structures, which are energetically stable at low (< 160 K) and high (> 330 K) temperatures, respectively. The sizable geometrical differences between the two structures in term of lattice parameters, PbI6 octahedral tilts, rotation and deformations, have considerable impact on the transport properties of the material. For example, at zero bias and for all considered electron energies, the cubic phase has a larger transmission than the orthorhombic one, although both show similar electronic densities of states. Depending on the applied voltage, the current in the cubic system can be several orders of magnitude larger as compared to the one obtained for the orthorhombic sample. We attribute this enhancement in the transmission to the presence of extended states in the cubic phase due to the symmetrically shaped and ordered PbI6 octaherdra. (C) 2015 Elsevier B.V. All rights reserved. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Elsevier science bv |
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000371944500011 |
Publication Date |
2015-11-06 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0927-0248 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.784 |
Times cited |
16 |
Open Access |
|
|
|
Notes |
; ; |
Approved |
Most recent IF: 4.784 |
|
|
Call Number |
UA @ lucian @ c:irua:133151 |
Serial |
4163 |
|
Permanent link to this record |
|
|
|
|
Author |
Roy, P.; Torun, E.; de Groot, R.A. |
|
|
Title |
Effect of doping and elastic properties in (Mn,Fe)2(Si,P) |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
|
|
Volume |
93 |
Issue |
93 |
Pages |
094110 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
Mixed magnetism (the coexistence of strong and weak magnetism in one material) is regarded as the origin of the giant magnetocaloric effect (GMCE). A good example is (Mn,Fe)(2)(Si,P), which is established as one of the best magnetocaloric materials available. Tuning the material properties are essential for optimizing its performance, and a straightforward way to do that is by doping. In this article, an ab initio electronic structure method was used to calculate the structure and magnetic properties of 3d-transition-metal-doped (Mn,Fe)(2)(Si,P) materials for magnetocaloric applications (transition metals are Cr, Co, Mn, Ni, Cu). For a steady performance, the material should be mechanically stable. A detailed analysis of the elastic constants shows that the mechanical stability of the (Mn,Fe)(2)(Si,P) system increases significantly by doping with boron without affecting the magnetic properties. Insights of the influence of doping enable future studies to understand and predict bettermagnetocaloric materials. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000372712100001 |
Publication Date |
2016-03-25 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
9 |
Open Access |
|
|
|
Notes |
; This work is part of an Industrial Partnership Programme (IPP I28) of Fundamenteel Onderzoek der Materie (FOM) (The Netherlands) and co-financed by BASF New Business. The authors would like to thank Phuong Thao Nguyen and Dr. Gilles A. de Wijs for very useful discussions. ; |
Approved |
Most recent IF: 3.836 |
|
|
Call Number |
UA @ lucian @ c:irua:133192 |
Serial |
4164 |
|
Permanent link to this record |
|
|
|
|
Author |
Berdiyorov, G.R.; El-Mellouhi, F.; Madjet, M.E.; Alharbi, F.H.; Peeters, F.M.; Kais, S. |
|
|
Title |
Effect of halide-mixing on the electronic transport properties of organometallic perovskites |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Solar energy materials and solar cells
T2 – 2nd International Renewable and Sustainable Energy Conference (IRSEC), OCT 17-19, 2014, Ouarzazate, MOROCCO |
Abbreviated Journal |
Sol Energ Mat Sol C |
|
|
Volume |
148 |
Issue |
148 |
Pages |
2-10 |
|
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
|
|
Abstract |
Using density-functional theory in combination with the nonequilibrium Green's function formalism, we study the effect of iodide/chloride and iodide/bromide mixing on the electronic transport in lead based organometallic perovskite CH3NH3PbI3, which is known to be an effective tool to tune the electronic and optical properties of such materials. We found that depending on the level and position of the halide mixing, the electronic transport can be increased by more than a factor of 4 for a given voltage biasing. The largest current is observed for small concentration of bromide substitutions located at the equatorial sites. However, full halide substitution has a negative effect on the transport properties of this material: the current drops by an order of magnitude for both CH3NH3PbCl3 and CH3NH3PbBr3 samples. (C) 2015 Elsevier B.V. All rights reserved. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Elsevier science bv |
Place of Publication |
Amsterdam |
Editor |
|
|
|
Language |
|
Wos |
000371944500002 |
Publication Date |
2015-12-18 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0927-0248 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.784 |
Times cited |
23 |
Open Access |
|
|
|
Notes |
; ; |
Approved |
Most recent IF: 4.784 |
|
|
Call Number |
UA @ lucian @ c:irua:133150 |
Serial |
4165 |
|
Permanent link to this record |
|
|
|
|
Author |
Bakalov, P.; Esfahani, D.N.; Covaci, L.; Peeters, F.M.; Tempere, J.; Locquet, J.-P. |
|
|
Title |
Electric-field-driven Mott metal-insulator transition in correlated thin films : an inhomogeneous dynamical mean-field theory approach |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
|
|
Volume |
93 |
Issue |
93 |
Pages |
165112 |
|
|
Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) |
|
|
Abstract |
Simulations are carried out based on the dynamical mean-field theory (DMFT) in order to investigate the properties of correlated thin films for various values of the chemical potential, temperature, interaction strength, and applied transverse electric field. Application of a sufficiently strong field to a thin film at half filling leads to the appearance of conducting regions near the surfaces of the film, whereas in doped slabs the application of a field leads to a conductivity enhancement on one side of the film and a gradual transition to the insulating state on the opposite side. In addition to the inhomogeneous DMFT, a local density approximation (LDA) is considered in which the particle density n, quasiparticle residue Z, and spectral weight at the Fermi level A(ω=0) of each layer are approximated by a homogeneous bulk environment. A systematic comparison between the two approaches reveals that the less expensive LDA results are in good agreement with the DMFT approach, except close to the metal-to-insulator transition points and in the layers immediately at the film surfaces. LDA values for n are overall more reliable than those for Z and A(ω=0). The hysteretic behavior (memory effect) characteristic of the bulk doping driven Mott transition persists in the slab. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
|
|
Language |
|
Wos |
000373572700002 |
Publication Date |
2016-04-09 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
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 |
5 |
Open Access |
|
|
|
Notes |
; This work was partially funded by the Flemish Fund for Scientific Research (FWO Belgium) under FWO Grant No. G.0520.10 and the joint FWF (Austria)-FWO Grant No. GOG6616N, and by the SITOGA FP7 project. Most of the calculations were performed on KU Leuven's ThinKing HPC cluster provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government-department EWI. ; |
Approved |
Most recent IF: 3.836 |
|
|
Call Number |
UA @ lucian @ c:irua:132872 |
Serial |
4167 |
|
Permanent link to this record |
|
|
|
|
Author |
Craco, L.; Carara, S.S.; da Silva Pereira, T.A.; Milošević, M.V. |
|
|
Title |
Electronic states in an atomistic carbon quantum dot patterned in graphene |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
|
|
Volume |
93 |
Issue |
93 |
Pages |
155417 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
We reveal the emergence of metallicKondo clouds in an atomistic carbon quantum dot, realized as a single-atom junction in a suitably patterned graphene nanoflake. Using density functional dynamical mean-field theory (DFDMFT) we show how correlation effects lead to striking features in the electronic structure of our device, and how those are enhanced by the electron-electron interactions when graphene is patterned at the atomistic scale. Our setup provides a well-controlled environment to understand the principles behind the orbital-selective Kondo physics and the interplay between orbital and spin degrees of freedom in carbon-based nanomaterials, which indicate new pathways for spintronics in atomically patterned graphene. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000373760900004 |
Publication Date |
2016-04-12 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
6 |
Open Access |
|
|
|
Notes |
; L.C.'s work is supported by CNPq (Proc. No. 307487/2014-8). Acknowledgment (L.C.) is also made to G. Seifert for discussions and the Department of Theoretical Chemistry at Technical University Dresden for hospitality. T.A.S.P. thanks PRONEX/CNPq/FAPEMAT 850109/2009 for financial support. M.V.M. acknowledges support from Research Foundation-Flanders (FWO), TOPBOF, and the CAPES-PVE program. ; |
Approved |
Most recent IF: 3.836 |
|
|
Call Number |
UA @ lucian @ c:irua:133260 |
Serial |
4171 |
|
Permanent link to this record |
|
|
|
|
Author |
Orlova, N. |
|
|
Title |
Emergent phenomena in superconductors and superfluids with multicomponent quantum condensates |
Type |
Doctoral thesis |
|
Year |
2016 |
Publication |
|
Abbreviated Journal |
|
|
|
Volume |
|
Issue |
|
Pages |
|
|
|
Keywords |
Doctoral thesis; Condensed Matter Theory (CMT) |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Antwerpen |
Editor |
|
|
|
Language |
|
Wos |
|
Publication Date |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record |
|
|
Impact Factor |
|
Times cited |
|
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: NA |
|
|
Call Number |
UA @ lucian @ c:irua:134094 |
Serial |
4172 |
|
Permanent link to this record |
|
|
|
|
Author |
Mirzakhani, M.; Zarenia, M.; Ketabi, S.A.; da Costa, D.R.; Peeters, F.M. |
|
|
Title |
Energy levels of hybrid monolayer-bilayer graphene quantum dots |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
|
|
Volume |
93 |
Issue |
93 |
Pages |
165410 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
Often real samples of graphene consist of islands of both monolayer and bilayer graphene. Bound states in such hybrid quantum dots are investigated for (i) a circular single-layer graphene quantum dot surrounded by an infinite bilayer graphene sheet and (ii) a circular bilayer graphene quantum dot surrounded by an infinite single-layer graphene. Using the continuum model and applying zigzag boundary conditions at the single-layer-bilayer graphene interface, we obtain analytical results for the energy levels and the corresponding wave spinors. Their dependence on perpendicular magnetic and electric fields are studied for both types of quantum dots. The energy levels exhibit characteristics of interface states, and we find anticrossings and closing of the energy gap in the presence of a bias potential. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000373572700004 |
Publication Date |
2016-04-09 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
26 |
Open Access |
|
|
|
Notes |
; This work was supported by the Fonds Wetenschappelijk Onderzoek (FWO)-CNPq project between Flanders and Brazil and the Brazilian Science Without Borders program. ; |
Approved |
Most recent IF: 3.836 |
|
|
Call Number |
UA @ lucian @ c:irua:133261 |
Serial |
4174 |
|
Permanent link to this record |
|
|
|
|
Author |
Cai, H.; Kang, J.; Sahin, H.; Chen, B.; Suslu, A.; Wu, K.; Peeters, F.; Meng, X.; Tongay, S. |
|
|
Title |
Exciton pumping across type-I gallium chalcogenide heterojunctions |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
|
|
Volume |
27 |
Issue |
27 |
Pages |
065203 |
|
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
|
|
Abstract |
Quasi-two-dimensional gallium chalcogenide heterostructures are created by transferring exfoliated few-layer GaSe onto bulk GaTe sheets. Luminescence spectroscopy measurements reveal that the light emission from underlying GaTe layers drastically increases on heterojunction regions where GaSe layers make contact with the GaTe. Density functional theory (DFT) and band offset calculations show that conduction band minimum (CBM) (valance band maximum (VBM)) values of GaSe are higher (lower) in energy compared to GaTe, forming type-I band alignment at the interface. Consequently, GaSe layers provide photo-excited electrons and holes to GaTe sheets through relatively large built-in potential at the interface, increasing overall exciton population and light emission from GaTe. Observed results are not specific to the GaSe/GaTe system but observed on GaS/GaSe heterolayers with type-I band alignment. Observed experimental findings and theoretical studies provide unique insights into interface effects across dissimilar gallium chalcogenides and offer new ways to boost optical performance by simple epitaxial coating. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
|
|
Language |
|
Wos |
000368897100008 |
Publication Date |
2016-01-13 |
|
|
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 |
3.44 |
Times cited |
15 |
Open Access |
|
|
|
Notes |
; This work was supported by the Arizona State University seeding program, the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus-short Marie Curie Fellowship. We acknowledge the use of the John M Cowley Center for High Resolution Electron Microscopy at Arizona State University. The authors thank Anupum Pant for useful discussions. We gratefully acknowledge the use of the facilities at the LeRoy Eyring Center for Solid State Science at Arizona State University. S Tongay acknowledges support from DMR-1552220. ; |
Approved |
Most recent IF: 3.44 |
|
|
Call Number |
UA @ lucian @ c:irua:131570 |
Serial |
4179 |
|
Permanent link to this record |
|
|
|
|
Author |
Sivek, J.; Sahin, H.; Partoens, B.; Peeters, F.M. |
|
|
Title |
Giant magnetic anisotropy in doped single layer molybdenum disulfide and fluorographene |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
|
|
Volume |
28 |
Issue |
28 |
Pages |
195301 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
Stable monolayer materials based on existing, well known and stable two-dimensional crystal fluorographene and molybdenum disulfide are predicted to exhibit a huge magnetocrystalline anisotropy when functionalized with adsorbed transition metal atoms at vacant sides. Ab initio calculations within the density-functional theory formalism were performed to investigate the adsorption of the transitional metals in a single S (or F) vacancy of monolayer molybdenum disulfide (or fluorographene). We found strong bonding of the transitional metal atoms to the vacant sites with binding energies ranging from 2.5 to 5.2 eV. Our calculations revealed that these systems with adsorbed metal atoms exhibit a magnetic anisotropy, specifically the structures including Os and Ir show a giant magnetocrystalline anisotropy energy of 31-101 meV. Our results demonstrate the possibility of obtaining stable monolayer materials with huge magnetocrystalline anisotropy based on preexisting, well known and stable two-dimensional crystals: fluorographene and molybdenum disulfide. We believe that the results obtained here are useful not only for deeper understanding of the origin of magnetocrystalline anisotropy but also for the design of monolayer optoelectronic devices with novel functionalities. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
London |
Editor |
|
|
|
Language |
|
Wos |
000374394700007 |
Publication Date |
2016-04-13 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0953-8984 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.649 |
Times cited |
7 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.649 |
|
|
Call Number |
UA @ lucian @ c:irua:133611 |
Serial |
4185 |
|
Permanent link to this record |
|
|
|
|
Author |
da Costa; Zarenia, M.; Chaves, A.; Pereira, J.M., Jr.; Farias, G.A.; Peeters, F.M. |
|
|
Title |
Hexagonal-shaped monolayer-bilayer quantum disks in graphene : a tight-binding approach |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Physical review B |
Abbreviated Journal |
Phys Rev B |
|
|
Volume |
94 |
Issue |
94 |
Pages |
035415 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
Using the tight-binding approach, we investigate confined states in two different hybrid monolayer-bilayer systems: (i) a hexagonal monolayer area surrounded by bilayer graphene in the presence of a perpendicularly applied electric field and (ii) a hexagonal bilayer graphene dot surrounded by monolayer graphene. The dependence of the energy levels on dot size and external magnetic field is calculated. We find that the energy spectrum for quantum dots with zigzag edges consists of states inside the gap which range from dot-localized states, edge states, to mixed states coexisting together, whereas for dots with armchair edges, only dot-localized states are observed. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000379502200008 |
Publication Date |
2016-07-11 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2469-9950;2469-9969; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.836 |
Times cited |
11 |
Open Access |
|
|
|
Notes |
; This work was financially supported by CNPq, under contract NanoBioEstruturas No. 555183/2005-0, PRONEX/FUNCAP, CAPES Foundation, under the process No. BEX 7178/13-1, the Flemish Science Foundation (FWO-Vl), the Bilateral programme between CNPq and FWO-Vl, the Brazilian Program Science Without Borders (CsF), and the Lemann Foundation. ; |
Approved |
Most recent IF: 3.836 |
|
|
Call Number |
UA @ lucian @ c:irua:134947 |
Serial |
4190 |
|
Permanent link to this record |
|
|
|
|
Author |
Croitoru, M.D.; Shanenko, A.A.; Vagov, A.; Vasenko, A.S.; Milošević, M.V.; Axt, V.M.; Peeters, F.M. |
|
|
Title |
Influence of disorder on superconducting correlations in nanoparticles |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Journal of superconductivity and novel magnetism |
Abbreviated Journal |
J Supercond Nov Magn |
|
|
Volume |
29 |
Issue |
29 |
Pages |
605-609 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
We investigate how the interplay of quantum confinement and level broadening caused by disorder affects superconducting correlations in ultra-small metallic grains. We use the electron-phonon interaction-induced electron mass renormalization and the reduced static-path approximation of the BCS formalism to calculate the critical temperature as a function of the grain size. We show how the strong electron-impurity scattering additionally smears the peak structure in the electronic density of states of a metallic grain and imposes additional limits on the critical temperature under strong quantum confinement. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
|
|
Language |
|
Wos |
000371089500013 |
Publication Date |
2016-01-08 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1557-1939 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
1.18 |
Times cited |
7 |
Open Access |
|
|
|
Notes |
; This work was supported by the Belgian Science Policy (BELSPO Back to Belgium Grant), the Flemish Science Foundation (FWO-Vl), the Methusalem Foundation of the Flemish Government, TOPBOF-UA, and the bilateral project CNPq-FWO-Vl. ; |
Approved |
Most recent IF: 1.18 |
|
|
Call Number |
UA @ lucian @ c:irua:132286 |
Serial |
4195 |
|
Permanent link to this record |
|
|
|
|
Author |
Van de Put, M.L.; Vandenberghe, W.G.; Sorée, B.; Magnus, W.; Fischetti, M.V. |
|
|
Title |
Inter-ribbon tunneling in graphene: An atomistic Bardeen approach |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
|
|
Volume |
119 |
Issue |
119 |
Pages |
214306 |
|
|
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
|
|
Abstract |
A weakly coupled system of two crossed graphene nanoribbons exhibits direct tunneling due to the overlap of the wavefunctions of both ribbons. We apply the Bardeen transfer Hamiltonian formalism, using atomistic band structure calculations to account for the effect of the atomic structure on the tunneling process. The strong quantum-size confinement of the nanoribbons is mirrored by the one-dimensional character of the electronic structure, resulting in properties that differ significantly from the case of inter-layer tunneling, where tunneling occurs between bulk two-dimensional graphene sheets. The current-voltage characteristics of the inter-ribbon tunneling structures exhibit resonance, as well as stepwise increases in current. Both features are caused by the energetic alignment of one-dimensional peaks in the density-of-states of the ribbons. Resonant tunneling occurs if the sign of the curvature of the coupled energy bands is equal, whereas a step-like increase in the current occurs if the signs are opposite. Changing the doping modulates the onset-voltage of the effects as well as their magnitude. Doping through electrostatic gating makes these structures promising for application towards steep slope switching devices. Using the atomistic empirical pseudopotentials based Bardeen transfer Hamiltonian method, inter-ribbon tunneling can be studied for the whole range of two-dimensional materials, such as transition metal dichalcogenides. The effects of resonance and of step-like increases in the current we observe in graphene ribbons are also expected in ribbons made from these alternative two-dimensional materials, because these effects are manifestations of the one-dimensional character of the density-of-states. Published by AIP Publishing. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
|
|
Language |
|
Wos |
000378923100022 |
Publication Date |
2016-06-07 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0021-8979; 1089-7550 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.068 |
Times cited |
6 |
Open Access |
|
|
|
Notes |
; ; |
Approved |
Most recent IF: 2.068 |
|
|
Call Number |
UA @ lucian @ c:irua:134652 |
Serial |
4198 |
|
Permanent link to this record |
|
|
|
|
Author |
Zarenia, M.; Perali, A.; Peeters, F.M.; Neilson, D. |
|
|
Title |
Large gap electron-hole superfluidity and shape resonances in coupled graphene nanoribbons |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
|
|
Volume |
6 |
Issue |
6 |
Pages |
24860 |
|
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
|
|
Abstract |
We predict enhanced electron-hole superfluidity in two coupled electron-hole armchair-edge terminated graphene nanoribbons separated by a thin insulating barrier. In contrast to graphene monolayers, the multiple subbands of the nanoribbons are parabolic at low energy with a gap between the conduction and valence bands, and with lifted valley degeneracy. These properties make screening of the electron-hole interaction much weaker than for coupled electron-hole monolayers, thus boosting the pairing strength and enhancing the superfluid properties. The pairing strength is further boosted by the quasi one-dimensional quantum confinement of the carriers, as well as by the large density of states near the bottom of each subband. The latter magnifies superfluid shape resonances caused by the quantum confinement. Several superfluid partial condensates are present for finite-width nanoribbons with multiple subbands. We find that superfluidity is predominately in the strongly-coupled BEC and BCS-BEC crossover regimes, with large superfluid gaps up to 100 meV and beyond. When the gaps exceed the subband spacing, there is significant mixing of the subbands, a rounding of the shape resonances, and a resulting reduction in the one-dimensional nature of the system. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Nature Publishing Group |
Place of Publication |
London |
Editor |
|
|
|
Language |
|
Wos |
000374654500002 |
Publication Date |
2016-04-25 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.259 |
Times cited |
7 |
Open Access |
|
|
|
Notes |
; M.Z. acknowledges support by the Flemish Science Foundation (FWO-Vl), the University Research Fund (BOF), and the European Science Foundation (POLATOM). A.P. and D.N. acknowledge support by the University of Camerino FAR project CESEMN. The authors thank the colleagues involved in the MultiSuper International Network (http://www.multisuper.org) for exchange of ideas and suggestions for this work. ; |
Approved |
Most recent IF: 4.259 |
|
|
Call Number |
UA @ lucian @ c:irua:133619 |
Serial |
4201 |
|
Permanent link to this record |